7th European Steel Technology and Application Days - ESTAD 2025

6 Oct 2025, 16:00 → 9 Oct 2025, 15:30 Europe/Rome

Palaexpo Veronafiere

Giacomo Mareschi Danieli (Danieli), Christian Bernhard (Montanuniversitaet Leoben), Carlo Mapelli (Politecnico di Milano)

ESTAD 2025 will be hosted by AIM, the Italian Association for Metallurgy, in Verona – Italy on 6-9 October 2025.
The knowledge and the development of the new ideas enhance progress. With the 7th European Steel Technology and Application Days 2025 (7th ESTAD 2025) AIM offers attendants and visitors the opportunity to meet, exchange their ideas, perform fruitful discussion and create new professional relationships involving technology providers, suppliers, producers and customers. The meeting will be focused on the technological advances, changes of the supply chain involving the raw materials and energy sources, transformation of the production processes and plants to accomplish the twin transition (ecological and digital) and the new perspective of steel applications.

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Conference Location

 

 

Monday 6 October

16:00 Registration

Early Congress registration and new on-site registration (pick-up of Conference material; possibility for speakers to upload their presentation at the slide centre)

Tuesday 7 October

08:00 Registration

Opening session

Conveners: Carlo Mapelli (Dipartimento di Meccanica - Politecnico di Milano), Christian Bernhard (Montanuniversitaet Leoben)

08:45 Welcome addresses by AIM President and Conference chairpersons

1 The Steel Industry in the Mediterranean Area: Challenges, Opportunities and Enabling Technologies

At the heart of the industrial and geopolitical dynamics reshaping the Mediterranean region, the steel industry faces decisive challenges: from rising energy costs to uncertainties in the availability and quality of raw materials, to increasing regulatory pressure in environmental and trade matters (CBAM, tariffs).
In this context, Italy plays a key role as a natural bridge between Europe and North Africa—two regions that are increasingly interconnected not only through economic flows but also in their decarbonization strategies.
Enabling technologies, innovation in production processes, digitalization, and sustainability are becoming essential levers for ensuring competitiveness and resilience.
Looking to the future therefore means building an industrial ecosystem capable of combining technological excellence, environmental efficiency, and strategic vision.

Speaker: Mr Giacomo Mareschi Danieli (Danieli & C. Officine Meccaniche SpA)

2 Making Steel Great Again: U.S. Steel Production in the Trump Era

While global steel demand is weakening, the North American market has demonstrated resilience. And now U.S. President Donald Trump is promising to further energize American steelmaking through heightened tariffs and a broader acceptance of diverse energy supplies. But to what long-term effect? This presentation will explore new investment plans and perspectives on how innovation, technology, and policy are shaping strategic investment decisions for the North American steel industry.

Speaker: Ronald Ashburn (Association for Iron & Steel Technology)

3 The Production Mix of Chinese Steel Industry and the Technical Efforts Toward Carbon Neutral

Abstract
The Chinese steel industry has been growing rapidly since the new millennium and reached its peak in the year 2020, with an annual crude steel output of 1.053 billion tons. Since then the growth became stagnant due to a slowdown of GDP growth rate and a sluggish real estate market in the past two years. In the meanwhile, the transformation of the manufacturing industry stimulated the upgrading of the steel grades. A very specific example is the automobile industry, with the speed up of BEV (battery electric vehicle) technology and its penetration ratio in the market, the demand for an even lighter body weight resulted in remarkable increase in the proportion of HSS and PHS.

The carbon-peak and carbon-neutral policy is an even greater challenge to Chinese steel industry, since its steel output accounts for over 50% of world total. In addition, the BF-BOF process dominates the whole industry with a proportion of 90%, whereas that of the EAF process is only 10%. The Chinese Steel Association published the vision and road-map for carbon neutral in 2022. This report gives a detailed description of the road-map and the notable efforts of the steel industry in the past few years. The latest development of HyCROF, industrial scale shaft furnace hydrogen DRI, H2-rich smelting reduction, the optimization of processing technologies and energy efficiency are introduced.

Speaker: Zhiling Tian

10:20 Coffee break

Alternative Reduction Methods & Waste Utilization

1.4.1

Convener: F Cirilli (Rina Consulting Centro Sviluppo Materiali)

4 Circored as a Pre-Reduction Step for Low-Grade Iron Ores

The steel industry is actively seeking innovative technologies to significantly reduce carbon footprints, especially for low-grade iron ores (BF quality), which constitute the majority of available iron ore resources and are primarily processed through the blast furnace route. The Circored process, developed by Metso, utilizes fluid bed reactors for the direct reduction of iron ore fines (instead of pellets) with hydrogen and has demonstrated its efficacy at an industrial scale for high-grade DR quality ores. This paper elaborates on the potential of a simplified Circored process as a pre-reduction step in sustainable steel production, focusing on its application to low-grade iron ores. A single-stage Circored process aims to reduce the ore to a metallization degree of approximately 80%. This semi-reduced direct reduced iron (DRI) can be further processed in smelting furnaces for final reduction, gangue separation, and carburization. This integrated approach is particularly suitable for low-grade iron ores with high gangue and loss on ignition (LoI) contents, which cannot be treated in EAF due to the resulting large slag formation and are often also challenging to pelletize.

Studies and test results from Metso’s R&D center in Frankfurt confirm the feasibility of the Circored process for low-grade iron ores, achieving targeted metallization degrees of 75-85% with various BF-grade ores. The paper also outlines a roadmap for using Circored as a pre-reducer to decarbonize iron production, including transitional strategies like Low Reduced Iron (LRI) injection into blast furnaces and mid-term strategies involving LRI in electric smelters. In conclusion, the Circored process as a pre-reduction step offers a sustainable solution for steel production from low-grade iron ores. By reducing carbon emissions and utilizing abundant low-grade resources, the Circored process addresses the environmental and economic challenges of traditional steelmaking methods. This innovative approach aligns with global efforts to achieve carbon neutrality.

Speaker: Jonas Dietzig

5 Decarbonization of industrial high-temperature processes with an innovative Electric Gas Heating

Transitioning industrial processes to electric power offers the potential to decrease CO2 emissions by utilizing renewable energy sources. Electric gas heating enables more compact and efficient setups compared to traditional combustion heating methods.
Expected huge market demand of high temperature gas electrical heating in different industrial sectors cannot be covered only by available state-of-art technologies, both in terms of scale and in meeting techno-economic needs.
In this context, SMS developed a proprietary solution consistent with the requirements in iron & steel industry, with potential application in other industries. Better feasibility than existing technologies is expected, due to ease scalability, high efficiency, temperature rise and optimized equipment cost. The innovation of this technology consists in a combination of wire resistance for heating with refractory checker used in Blast Furnace Hot Stoves. This equipment is suitable to work with different type of gas, including Hydrogen and CO2.
A prototype of a 0.5 MW electric heater, maintaining identical internal geometry to its industrial version, has undergone successful testing. It demonstrated stable performance at 1000 °C and responded smoothly to operational variations. The paper discusses the distinctive benefits of this solution and explores its potential applications.

Speaker: Mr Andrea Castelli (SMS group)

6 Clean iron production by self-reducing agglomerates made in biochar and mill scale: a comparison in reduction efficiency as a function of biochar quality and properties

Carbon Composite Agglomerates (CCA) or self-reducing agglomerates are based on the compaction of a solid carbonaceous and oxide matrix in the form of pellets, briquettes, etc. with the possible addition of an organic or inorganic binder. As a result, when heated, the carbon acts as a reducing agent and the specific metals contained in the oxide matrix are recovered.
It is therefore not surprising that to date CCAs are gaining increasing interest in the recovery of the iron contained in most metallurgical residues and can therefore be considered as an alternative source of clean iron to direct reduced iron (DRI) or hot briquetted iron (HBI). However, in order to follow a philosophy of full residue recovery and low impact iron production, the use of biogenic carbon sources as reducing agents must be considered in relation to fossil carbon sources.
Consequently, to address the future application feasibility of CCAs, this study focuses on the differences in reduction effectiveness of different biochars obtained from the pyrolysis of wood, agricultural, food residues on one of the main metallurgical residue, mill scale, and the reduction performance comparison when fossil carbon sources are applied as reductants.
The results highlighted the possibility of obtaining either a sponge iron or cast iron as a function of the relative amount of fixed-to-volatile carbon of the reducing agent and the compliance of the reduced CCAs with the benchmark values of commercial DRI. In addition, the chemistry of the gangue was fully comparable to that of electric arc furnaces, consisting mainly of Ca-Al-Si-O compounds, reinforcing the role of self-reducing agglomerates as a parallel clean iron source of the future in metallurgical processes.

Speaker: Dr Gianluca Dall'Osto (Politecnico di Milano - Dipartimento di Meccanica)

7 Enhancing Steelmaking Waste Utilization through Electric Smelting Furnace Technology

Steelmaking plants generate various waste materials, primarily slag, iron-containing fines, and sludges. Traditionally, many of the iron-bearing wastes have been recycled in integrated steel plants such as in sinter plants and blast furnaces. However, the shift to Electric Arc Furnaces (EAF) and stricter environmental regulations are diminishing the role of traditional recycling methods. As plants continue to generate up to 500 kg of waste per tonne of crude steel, and competition for high-grade iron ores intensifies, identifying sustainable applications for steelmaking waste is becoming increasingly critical.
Through effective reduction and fluxing strategies, the Electric Smelting Furnace (ESF) can convert iron-bearing wastes into hot metal for steelmaking, and slag suitable for the cement industry. In this process, waste materials serve as primary iron sources, while steelmaking slags can be used as fluxing agents and/or secondary iron sources. This study utilizes first-principle process models and industrial benchmarking to assess the ESF's effectiveness in enhancing iron recovery in steel plants, improving waste valorization, and offering a sustainable alternative to declining traditional steelmaking waste recycling methods.

Speaker: Kamal Joubarani (Hatch Ltd.)

8 Comparative Analysis of CO and H2 Reduction Mechanisms in Electric Arc Furnace Dust

Recovering valuable metals such as zinc and iron from steel mill residues is crucial in the steelmaking industry. Electric arc furnace dust (EAFD) represents the primary secondary resource for Zn recovery, as electric arc furnace (EAF) technology predominantly utilizes galvanized steel scrap as its main feedstock. Waelz process, which has been recognized as the best available technology (BAT), is the predominant method of EAFD treatment. The Waelz technology remains dominant in the industry due to its reliability, robustness, and operational simplicity. However, challenges arise from slag generation and CO₂ emissions. With increasingly stringent EU regulations and a growing emphasis on sustainability, efforts to enhance the Waelz process and develop alternative metallurgical technologies are intensifying. This study proposes a novel approach to mitigate the drawbacks of the Waelz process by substituting conventional carbon-based reducing agents with hydrogen (H₂). As part of the Horizon Europe-funded Dust2Value project, this research focuses on a detailed comparison of CO- and H₂-based reduction mechanisms for EAFD with the goal of efficient recovery of both Fe and Zn. The study employs thermogravimetric analysis (TGA), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), and hot-stage microscopy to investigate reduction, sintering and melting behavior of EAFD samples. Our results show improved kinetics and overall reduction efficiency when using H2 as a reducing agent.

Speaker: Eleonora Shpilevaia

9 Electric Smelting Furnace Technology for Green Steelmaking

The steelmaking industry is beginning to transition from carbon-intensive blast furnace production to new, lower-emission process routes. Implementation-ready solutions are needed to support this transition, but it is crucial that the industry makes careful investments to avoid risks to production.

The use of a direct reduction plant (DRP) with a downstream electric smelting (melting) furnace (ESF, or EMF) has been a topic of significant discussion in recent years, as a potential solution to the challenge facing steelmakers, especially when blast furnace grade iron ore is the desired feed material. Electric smelting furnace technology can be applied to various flowsheets, including integrated plants with BOF or EAF steelmaking, and non-integrated (off-shore) pig-iron production. This flexibility provides cost-effective options to shift to green steelmaking by continuing to use existing facilities and pellet supply chains, as well as providing higher yields and reduced lifecycle costs, while maintaining high-value steel products.

Although ESF equipment has been proven through decades of ferrous and non-ferrous commercial installations, the scale of ironmaking envisioned for the steelmaking industry is not yet proven. However, extensive optimization and technology improvements have been completed and demonstrated at the required scale in other industries, such as ferronickel. These benchmarks form the foundation of Hatch’s ESF (EMF) technology. In addition, many have been planning and implementing extensive test programs, from small to larger scales, to help better characterize the DRP-ESF (EMF) operation. These test programs will further improve the extensive knowledge available, and also help bring more widespread acceptance of this solution for steelmakers. This combined approach will help to ensure future operations ramp up to nameplate capacity quickly and provide long-term performance that is robust, reliable, and efficient.

Speaker: Kyle Chomyn (Hatch Ltd)

Circular Economy & Industrial Symbiosis

5.3.1

10 Hurricane – Sector coupling hub for circular use of thermal and industrial waste

Within HURRICANE a sector-coupling circular hub centred around the ArcelorMittal Ghent site will be created. We will target efficient resource management together with the recovery and utilization of squandered industrial waste heat and water. Together with ArcelorMittal Ghent’s ongoing initiatives, this will lead to a reduction of energy, water and raw materials. Thanks to the ongoing projects taking place within and around the Ghent site, the site is already well connected to many other industries like waste suppliers, chemical producers, renewable power producers, and wastewater treatment. It has become a multi-sectoral hub leading to efficient implementation of industrial symbiosis concepts. The Ghent site has a significant amount of recyclable energy, material and water that allows this symbiosis. These aspects are not only from the steel making processes, but also from other operations taking place in the mentioned “multi-sectoral” hub. This hub can be further enhanced with the integration of waste heat with its ongoing initiatives. Our solution aims at developing and demonstrating novel heat recovery (heat exchanger) and upgrading (heat pumps) solutions from selected operations and then coupling it with the internal and external off takers by means of a heat grid. With digital tools, aspects like broadening the district heating network, and adapting the heat demand profile of the buildings to better match the intermittent of the waste heat, can be optimized. Finally, an integrated software tool for circular hubs that combines the different tools and data produced at the different operations will be developed and validated. Through two virtual demonstrations and circular hubs blueprint the replication potential will be proven. The consortium is formed by 11 partners from 4 different countries, including 4 research organizations, 1 large End User, 2 SMEs, 3 civil organizations and 1 linked 3rd party.

Speaker: Mr Philippe Alboort

11 Recent achievements of Industrial Symbiosis in the steel sector based on the Symbio-Steel project

Industrial Symbiosis concerns the use by one company or sector of underutilized resources from another one, resulting in reducing dependence on critical materials, mitigating supply risks, replacing virgin materials, and, consequently, reducing CO2 emissions, and transforming existing resources in the value chain into a usable form. Implementing the Industrial Symbiosis concept provides new synergies with other industries by optimizing resource exploitation, maximizing by-products reuse, minimizing waste, recovering heat where possible, and enhancing overall efficiency, according to the principles of Circular Economy.
The work developed in the ongoing European project entitled “Fostering Industrial Symbiosis solutions for the steel sector by results monitoring and dissemination from national and EU funded projects coupled to definition of cross-sectorial synergy scenarios” (Symbio-Steel – G.A. No. 101156509), which is co-funded by the Research Fund for Coal and Steel (RFCS), exploits and spreads the most promising research results in recent and ongoing projects on Industrial Symbiosis. This will pave the way for a wider uptake of Industrial Symbiosis solutions in steel industry, supporting new synergies with other industrial sectors. In particular, the project aims at assessing Industrial Symbiosis in the context of the ongoing transition of the steel industry towards the next generation C- or CO2- lean production processes. This objective is being achieved by monitoring and assessing the impact of initiatives in the steel sector that are related to Industrial Symbiosis, to assess the effectiveness of such concepts in the steel industry and in other energy-intensive industries. The foreseen development of guidelines will result in improving Industrial Symbiosis activities to achieve an effective industrial rollout of sector coupling technologies.

Speaker: Prof. Valentina Colla (Scuola Superiore Sant'Anna)

12 Upgrading of low-quality iron ores and mill scale with low carbon technologies

Iron ore and scrap as raw materials are the base of iron and steel production. Due to the transition from carbon to hydrogen-based green iron and steel production, most current production units as sinter plan, blast furnace and basic oxygen furnace will be replaced by the direct reduction process followed by the electric arc furnace. As a result, recycling routes via BF-BOF-technologies will be cut off and the demand for high-quality direct reduction pellets and scrap will rise. In addition, new by-products from the DR- and EAF-process will emerge, requiring new technologies for upgrading of low-quality iron ores and scrap to avoid lack of raw materials and provide solutions for the EU’s Net-Zero-Waste goal.
Considering this, the ongoing project TransZeroWaste focus on e.g. upgrading low-grade iron ore by combining it with iron-rich by-products, the development of innovative techniques to enhance recycling and produce high quality pre-material for decarbonised future production routes and the separation of disturbing components from byproducts to replace scrap supporting the transition towards zero waste.
Approaches are cold pelletisation and briquetting of low-quality iron ores for direct use in existing and future steel works in combination with new binders, low-CO2 hot pelletisation of fine materials with microwaves as breakthrough technology to increase iron metallisation grade, valorisation of low-quality materials and separation of zinc in parallel and finally the removal of organic impurities like oil from low-quality iron ores equivalents (e.g. oily fine scale), mandatory for an internal metallurgical reuse. The approach is the hydrometallurgical treatment including the cleaning agent recovery using a modified magnetic separator allowing a combined selective removal of iron containing material.
The technology developments are accompanied by investigation and adjustment of digital tools like e.g. mass flow analysis, Life Cycle Assessment and Life Cost Calculation to facilitate evaluation of efficiency for further industrialisation.

Speaker: Martin Hubrich (VDEh-Betriebsforschungsinstitut GmbH)

13 Assesment of the natural absorption of CO2 performed by steelmaking slag

Electric Arc Furnace (EAF) and Ladle Furnace (LF) slag, a byproduct of steelmaking, has emerged as a promising material for the natural capture of CO₂ through a process called mineral carbonation. Composed primarily of calcium and magnesium oxides, EAF slag reacts with atmospheric CO₂ to form stable carbonates, such as calcite and magnesite, under ambient conditions. This natural carbonation process not only sequesters CO₂ but also improves the slag's mechanical properties, making it suitable for use in construction materials like cement and aggregates. The carbonation of EAF slag offers a dual benefit: it reduces the carbon footprint of steel production by capturing CO₂ and transforms industrial waste into valuable resources. While the process occurs naturally, factors such as slag composition, particle size, and environmental conditions influence its efficiency. This study is ongoing to optimize carbonation rates and integrate this process into industrial practices, providing a sustainable pathway for mitigating greenhouse gas emissions and advancing circular economy principles in the steel industry.

Speaker: Prof. Carlo Mapelli (Dipartimento di Meccanica - Politecnico di Milano)

Continuous Casting Process Fundamentals & Defect Analysis

2.3.1

14 Analysis of Center Segregation Induced by Density Changes and Shrinkage Cavities Using a Moving-Slice Model in Continuous Casting

A simple yet effective method has been developed to simulate macro-segregation during continuous casting. The model focuses on a thin slice moving at the casting speed, incorporating temperature and solid/liquid fraction profiles derived from prior heat transfer and solidification analyses. Solidification is specifically modeled along the thickness direction of the slice.
The model incorporates micro-segregation and two key flow mechanisms: density-driven flow, governed by mass balance, and cavity-driven flow, which occurs as liquid and equiaxed crystals fill the solidification cavity forming at the center during solidification.
Density-driven flow leads to positive macro-segregation near the center in both slabs and blooms, but the effect is significantly stronger in blooms. This is attributed to their higher Flow Contribution Ratio (FCR), which quantifies the relative contribution of Y-axis flow to overall flow and is likely influenced by greater solidification shrinkage.
The cavity-driven flow model successfully explains the observed positive segregation peak at the center and the negative segregation peak at the total shrinkage location—phenomena that density-driven flow alone cannot account for.
The model’s predictions closely match experimental data and exhibit expected trends when casting conditions—such as casting speed, secondary cooling intensity, and steel composition—are varied. This provides valuable insights for optimizing casting parameters to minimize center-segregation.
Additionally, the model aids in optimizing soft reduction patterns, which directly influence the velocity of the solid/liquid interface and the size of shrinkage cavities. By aligning the reduction pattern with the solidification shrinkage rate and considering the increasing liquid concentration during solidification, the model offers a precise and efficient method to reduce center-segregation.
With its fast computation speed, the model is well-suited for both offline analysis and real-time implementation, making it a valuable tool for research and industrial applications.

Speaker: Dr Joodong Lee (Expresslab Inc.)

15 Predicting the risk of surface defects in continuous casting with advanced measurements and artificial intelligence

Advanced steel grades present significant challenges in casting, and while surface defects cannot be completely avoided, it is crucial to minimize, identify, and predict their occurrence to save energy and resources. In the SMART-CAST II project (funded by Sweden's Innovation Agency), sophisticated measurement systems have been installed in the continuous casting lines of two Swedish steel producers. Artificial intelligence (AI) is employed for both the automatic detection of surface defects, and for the prediction of defects based on temperatures measured in the mould.
A fiber optic sensor system installed in the copper plates of the mould provides a detailed temperature map with high spatial and temporal resolution, measuring temperatures at thousands of positions every second. An automatic surface inspection system, installed immediately after the secondary cooling, uses AI to detect defects in images of the surface. Additionally, AI is used to find the connection between mould temperatures and process data, and the resulting product surface quality. Temperature data from the mould and surface quality data from inspection are used to train machine learning models to identify temperature patterns associated with the occurrence of surface defects on the product.
This work demonstrates the use of AI to process large amounts of temperature and image data, enabling early feedback to continuous casting personnel:
• Automatic detection of defects on the hot surface before cutting
• Identification of potential problem areas on the strand during casting
• Early warnings for mould conditions with a high risk of defects
Implementing this technique can significantly improve product quality and reduce waste in continuous casting.

Speaker: Jill Sundberg (Swerim)

16 Influence of different C, Ti, B, Mn, and Al content on hot ductility behavior of two micro-alloyed steel at different strain rates

The ductility behavior of continuously cast steel is a key factor influencing strand quality and crack susceptibility. Therefore, investigating the parameters affecting ductility is of great importance for enhancing the productivity of the method by producing defect-free products. This study investigates the differences in ductility behavior between two micro-alloyed steels subjected to hot tensile testing at strain rates of 10⁻³ s⁻¹ and 10⁻² s⁻¹ at 700 °C, 750 °C, and 800 °C. The first material is low-carbon micro-alloyed steel, and the second contains a higher C, Ti, and B, along with lower Mn and Al content. Both steels were tested after in-situ melting using an induction heating system in a vacuum chamber, followed by hot tensile testing until the fracture. The results indicate that the steel with higher B and Ti content exhibits better ductility at both strain rates. This was attributed to the precipitation behavior and the austenite-ferrite phase transformation. These effects are associated with the preferential formation of coarse TiN rather than AlN and BN. Additionally, the segregation of free B at grain boundaries, which did not form BN, delayed ferrite formation, thereby retarding the crack susceptibility caused by thin ferrite films at austenite grain boundaries. An initial microstructure analysis was conducted to observe the influence of temperature and strain rate on both steels. Furthermore, the precipitation kinetics of both steels were evaluated using MatCalc software, which provided predictions for the expected precipitates. The simulation results are compared with the experimental findings to enhance understanding of the underlying mechanisms.

Speaker: Saeid Bakhtiari (K1-MET GmbH, Stahlstrasse 14, 4020 Linz, Austria. Institute of Materials Science, Joining and Forming at the Graz University of Technology, Kopernikusgasse 24/I, 8010 Graz, Austria)

17 Influence of the cooling strategy on the intergranular crack formation during continuous casting of TRIP steels produced from low-grade scrap

Thin Slab Casting and Rolling processes, such as the Arvedi Endless Strip Production (Arvedi ESP) process, are proven technologies to significantly reduce energy consumption and direct CO2 emission in continuous casting and hot rolling. Due to the increasing use of Electric Arc Furnaces and the use of also low-grade steel scrap, a higher intake of undesired tramp elements, such as Cu or Sn, is expected. In continuous casting and hot rolling, those unwanted tramp elements may lead to hot shortness and intergranular crack formation. Arvedi ESP aims to suppress those negative effects by increasing casting speed and accelerating cooling of the thin slab, as well as by direct rolling without using a tunnel furnace.
The influence of tramp elements and the cooling strategy on the intergranular crack formation of steels are experimentally investigated by the in-situ materials characterization by bending (IMC-B) test. The IMC-B test is a three-point bending test at elevated temperatures, allowing the experimental simulation on directly cast samples under different boundary conditions, such as cooling strategy or bending temperature. The conventional continuous casting process and the Arvedi ESP process are simulated on a TRIP980 steel and a Cu- and Sn-contaminated TRIP980 steel.
Results clearly indicate that the addition of Cu and Sn has a detrimental effect on the intergranular crack formation for conventional continuous casting conditions, especially in the temperature range of 900-1000 °C. On the contrary, accelerated cooling and the shorter process time of Arvedi ESP result in significantly better performance regarding crack formation, even in Cu- and Sn-contaminated samples. Nevertheless, it is evident that bending temperatures above 1000 °C decrease crack sensitivity in both processes. Summing up, the behavior of TRIP steels during continuous casting is significantly influenced by elevated Cu and Sn contents, but faster cooling and shorter process times seem beneficial.

Speaker: Robert Littringer (Chair of Ferrous Metallurgy, Montanuniversitaet Leoben)

18 A novel approach to cracking criteria in continuous casting

An overview is given of the ongoing RFCS project SHELL-CRACK. The project offers a new paradigm for the prediction, detection and correction of hot-cracks and surface defects during casting based on Pilot/Lab scale thermo-mechanical experiments combined with numerical simulations. This innovative approach considers not only “material” properties but also specific “process” information to achieve new/extended cracking criteria for the whole process from microstructure to caster size. These enhanced criteria are validated, tuned and put to the test in a series of plant trials where advanced quality sensors are used to correlate defects to parameters such as mould temperature, surface quality and micro-structure features. This approach could prove particularly useful to assess the role of different trace elements (i.e. impurities) arising from increased use of lower-quality scrap sources and/or DRI-HBI from fossil free processes. Thus, SHELL-CRACK will deliver a complete set of tools to enhance current production but also prepare European casters for the new challenges posed by alternative ironmaking methods as envisaged in the new Green Deal. This project has received funding from the Research Fund for Coal and Steel under grant agreement No 101156718.

Speaker: Nils Andersson (Swerim AB)

19 The effect of continuous casting conditions on the mechanical properties of low-carbon steel wire rods

Solidification plays a fundamental role in metallurgical processes, such as continuous casting of steel billets, as it greatly influences the final microstructure, in terms of grains morphology and size and chemical segregation. Segregation of solute elements occurs because of their partitioning between the liquid and the growing solid. The liquid interdendritic regions are enriched of solute elements rejected by the growing dendrites. Such segregation cannot be fully mitigated through subsequent hot rolling processes. Common evidence of this undesirable phenomenon is the banded microstructure observed in hot-rolled products, characterized by alternating longitudinal bands of ferrite and pearlite. Normalization can reduce the banded microstructure, but micro-segregation remains difficult to completely homogenize. Therefore, hot-rolled wire rods produced from steel billets solidified under different conditions exhibit varying mechanical properties.
In this context, the study presents a comparative analysis of two low-carbon steel billets with similar chemical composition but produced under different casting conditions. One billet was produced by using a continuous casting machine equipped with a strand electromagnetic stirrer (S-EMS), while the other billet was produced on another machine without S-EMS. The analysis investigated the differences in macro and micro-structure of the two billets also by measuring the secondary dendrite arm spacing (SDAS) and the segregation index. Additionally, the mechanical properties of wire rods derived from these billets were assessed by tensile tests and micro-hardness Vickers measurements, and the final microstructure was analyzed by optical and scanning electron microscopy (SEM). The lower SDAS measured at the core of the billet produced with S-EMS, after hot rolling, resulted in a finer and more homogenous microstructure, also leading to enhanced mechanical properties of the final wire rods.

Speaker: Federico Baldussi (Università degli studi di Brescia - Italy)

Hydrogen-Based Direct Reduction (H-DRI)

5.1.1

Convener: Prof. Klaus Krüger (Ingenieurbüro Klaus Krüger)

20 Flexible direct reduction of iron ore with Natural Gas and Hydrogen - Potential and perspectives of the new SALCOS demonstration plant µDRAL in Salzgitter

Salzgitter AG is consistently pushing ahead with the SALCOS (Salzgitter Low CO2 Steelmaking) project on its way to climate friendly primary steel production. In this regard Salzgitter Flachstahl GmbH is gradually converting its crude steel capacity from the conventional blast furnace-converter route to a nearly CO2-free direct reduction-electric arc furnace route.
With the new SALCOS demonstration plant µDRAL, supplied by plant and technology partner Tenova, the flexible direct reduction of iron ore with natural gas and hydrogen is now being tested in order to gain important preliminary experiences for the industrial SALCOS green steel production. The focus is on energy-efficient and CO2-reducing process development, the testing of suitable iron carriers and sponge iron products as well as other aspects of operational management and circularity.
The paper reports on the potential, first operation experiences and further perspectives of the new µDRAL direct reduction pilot plant.

Speaker: Dr Peter Juchmann (Salzgitter Flachstahl GmbH)

21 Carburization with methane of different iron-bearing oxide pellets reduced by hydrogen

To reduce CO₂ emissions in iron and steel production, the industry is transitioning towards hydrogen-based reduction. However, a key challenge lies in the sustainable production of hydrogen, as most hydrogen is currently derived from hydrocarbon decomposition. Additionally, during the smelting of Direct Reduced Iron (DRI) in steelmaking, a certain amount of carbon in DRI feed is beneficial. In this study, hydrogen was used to reduce iron oxides in two iron-bearing pellets, which were quite different in compositions and physical characteristics. The reduction was conducted at 900 °C, followed by carburization at the same temperature using hydrogen with 10 vol% CH₄ for different durations. XRD, SEM, LECO, and XRF analyses were performed to examine the phase compositions, microstructure, carbon content, and chemical compositions before and after reduction. The results confirmed complete reduction of iron oxides during the reduction stage, and in carburization, DRI mass gains were observed due to the carburization and the formation of cementite and graphite phases. Prolonged carburization led to the decomposition of cementite, further influencing the phases distrubutions and compositions.

Speaker: Manish Kumar Kar (Norwegian University of Science and Technology)

22 Models for simulating gas and energy management in the transition of integrated steelworks to high hydrogen direct reduction-based processes

Integrated steelworks are deeply affected by the decarbonization transition of the steelmaking sector required by the European Green Deal. One of the most promising solutions is their conversion from blast furnace-basic oxygen furnace based plants to direct reduction shaft furnace-electric arc furnace based routes using hydrogen enriched reducing gases. However, this conversion involves challenges ranging from the micro (i.e. at particle level) to the macro (i.e. plantwide) scale. Issues are expected especially in the transition period, where processes belonging to two production routes will coexist. Currently conventional integrated steelworks are close to an optimum point and are almost self-sufficient from the energetic point of view. On the contrary, during the transition, existing equilibria will be troubled from the point of view of production and gas and energy management. Therefore, solutions must be proposed to smoothly guide the transition enabling optimal gas and energy management in the different stages and supporting environmental and economic sustainability. The project entitled “Maximise H2 Enrichment in Direct Reduction Shaft Furnaces” (ref. MaxH2DR, G.A. 101058429), which is co-funded by the European Union through the Horizon Europe programme, is developing a multipurpose simulation toolkit including, among others, models of gas and energy management units in conventional integrated steelworks, and of main direct reduction processes including gas management units that are well integrated in these processes. Such models will be used to investigate transition scenarios starting from a European integrated standardized steel mill considering also the issues related to the gas and energy management. The proposed contribution focuses on these models and their application.

Speaker: Dr Ismael Matino (Scuola Superiore Sant'Anna - TeCIP Institute - ICT-COISP)

23 Safe H-DRI: advancing the production, transport and storage of Hydrogen-based Direct Reduced Iron (H-DRI) for sustainable steelmaking

The transition to hydrogen-based direct reduction (H-DRI) is a crucial step in decarbonizing the steel industry. The ‘Safe H-DRI' project aims to optimize the production, loading, transport, unloading and storage of Hyrogen-based-DRI (H-DRI), addressing key challenges related to its stability, metallurgical properties, and industrial applicability.
This study investigates the hydrogen-based reduction on iron ore pellets, followed by the evaluation of physical and chemical properties of H-DRI, assessing its oxidation resistance with passivation methods, chemical and mechanical stability, and handling safety during storage and transport. Special attention is given to reoxidation risks, as H-DRI is highly reactive due to its large surface to volume ratio. Various passivation techniques and controlled atmosphere storage solutions are evaluated to investigate and understand the effects and reactions to better prevent degradation and ensure safe long-distance transport.
Furthermore, the research explores the potential and creates feasibility of the expected increase of the utilization of lower-grade iron ores, to improve sustainability and resource efficiency, while also the development of strategies for reusing fines and loss material during handling of H-DRI, with the aim of minimizing waste and supporting circular economy.
The findings are expected to provide crucial insights into safe handling strategies and operational best practices for large-scale H-DRI deployment, contributing to the development of a hydrogen-based steel industry aligned with the European Union’s goal for 2050.
The project “Safe transport of DRI from H2-based direct reduction considering quality-related H-DRI reactivity, stability, the efficiency of passivation methods and health and recycling aspects - Safe H-DRI” (GA N. 101150482) is funded by the European Union. Views and opinions expressed are however those of the authors only and do not necessarily reflect those of the European. Neither the European Union nor the granting authority can be held responsible for them.
Keywords: H-DRP, Transport H-DRI, Passivation, Green Steel, Decarbonization.

Speaker: Valentina Alemanno (RINA Consulting - Centro Sviluppo Materiali)

24 Computational Analysis of Means to Enhance Hydrogen-Based Direct Reduction in Shaft Furnaces

The steelmaking sector has to suppress its CO2 emissions to mitigate climate change, but the blast furnace-basic oxygen furnace route that dominates today cannot substantially reduce the emissions without carbon capture of the arising gases. Direct reduction (DR) in a shaft furnace followed by melting in an electric arc furnace is presently considered a viable option to reduce the environmental impact of steelmaking, and a gradual replacement of natural gas by hydrogen in the DR furnace could almost eliminate the carbon emissions from the reduction step. However, even though natural gas-based DR is well established, the counterpart with high (> 80%) concentration of hydrogen in the feed gas comes with several challenges. These include process economics (green hydrogen is expensive) and also technical aspects, e.g., how to provide sufficient heat to compensate for the endothermic nature of hydrogen reduction of iron oxides. The present work focuses on the second issue, i.e., the operation of a DR shaft furnace using hydrogen-rich gas.
The presentation describes results of a computational analysis of the DR furnace with the goal to detect challenges and bottlenecks in the hydrogen-based operation and to suggest possible remedies. A two-dimensional static CFD model that considers fluid flow, heat and mass transfer and chemical reactions is used for the analysis. After studying the impact of an increasing share of hydrogen in the feed gas, remedies addressing the arising problems are suggested and assessed by simulation, including modifications of the gas injection points or the furnace geometry. Particular attention is also focused on the role of carbon monoxide in the feed gas as it serves to mitigate the negative effects of hydrogen caused by the endothermic reactions in combination with a lower molar heat capacity of the H2-H2O compared to CO-CO2.

Speaker: Prof. Henrik Saxén (Åbo Akademi University)

25 Kinetics of Direct Reduction of iron ore pellets: understanding rate-limiting steps in hydrogen-based reduction of low- and high-grade pellets

The steel industry is committed to eliminating fossil fuels to reduce CO₂ emissions, requiring innovative technologies and alternative reducing agents. Hydrogen-based direct reduction is currently the most viable solution for transforming iron ore into metallic iron with minimal environmental impact.
This study investigates the kinetic mechanisms governing the hydrogen-based direct reduction of iron ore pellets, with a comparative analysis between low-grade and high-grade pellets. Despite their higher gangue content, low-grade pellets are of primary interest due to their preferential industrial use. Understanding their reduction kinetics is essential for optimizing reactor design and process conditions.
Laboratory-scale reduction tests were conducted to evaluate the effects of temperature (800–1200°C), gas velocity, reaction time, and pellet quality. Pellets were analyzed in terms of weight loss, SEM imaging, porosity, and metallization degree. The results indicate that reaction time, temperature, and hydrogen flow rate are key factors in the reduction process. In the tested conditions, the reaction yield increases up to 60 minutes, then stabilizes. Temperature has a minor effect above 1000°C, while a higher hydrogen velocity enhances reduction efficiency by improving mass transfer and reagent contact.
This research highlights the importance of tailoring reduction parameters based on pellet quality, particularly for low-grade raw materials, to ensure optimal process efficiency. The insights gained contribute to the optimization of hydrogen-based direct reduction for large-scale applications, aligning with the objectives of the HYDRA project, which focuses on developing next-generation hydrogen-based reduction technology.
The activities are carried out within the IPCEI project HYDRA, financed under the NextGenEU framework by the Italian Ministry of Enterprises and Made in Italy (MIMIT).

Speaker: F Cirilli (Rina Consulting Centro Sviluppo Materiali)

Raw Material Optimization & Scrap Management

2.2.1

Convener: Cosmo Di Cecca (Feralpi Siderurgica)

26 The effect of hot heel condition on EAF operations with HBI bucket charging

In these day, Carbon Neutrality is important issue in the world. And iron&steelmaking industry is also undergoing process change to achieve carbon neutrality. The biggest change is process transitions from BF-BOF to DRI-EAF. In case of BF-BOF process, They can produce from normal grade of steel to AHSS grade steel. But this process need to generate so many CO2 emission, 1.85tCO2/steel ton. On the other hands, DRI-EAF process is also possible to produce from normal to AHSS, But this process CO2 emission is just half of BF-BOF, 0.97tCO2/steel ton. In other words, producing steel using an EAF is more effective in terms of CO2 emission compared to BF-BOF process. And by using DRI in EAF, They are able to produce high grade steel. We have 10EA EAFs for structural and special steel production. furthermore, we are planning to establish a new EAF for producing advanced high strength sheet using a significant amount of HBI. So we have recently conducted trials of melting HBI up to 30% using buckets with changing hot heel condition in EAF. Hot heel conditions (temperature, amount) lead to different outcomes when adding up to 30% HBI in bucket to the EAF. Additionally, comparing all scrap operation in EAF, Nitrogen percent in molten metal is also different in two case. We will share this operation results and also share our future plans.

Speaker: JM Lee (HYUNDAI STEEL)

27 Melt Shop Production Management with Comprehensive Raw Material Optimization

The transition towards more sustainable steel production implies also huge challenges regarding raw material procurement and usage. Production management for liquid steelmaking has to optimize the raw material input, especially regarding hot metal, DRI/HBI, scrap, alloy and slag former materials. Forecasts of the expected raw material demands in production planning and scheduling support their procurement and inventory management. The optimized mix of raw materials for a heat has to consider all its charging and alloying steps of primary and secondary steelmaking with their respective logistic and metallurgical constraints as well as related energy consumptions and CO2 emissions. Thus, an integrated multi-parameter raw material optimization based on comprehensive modelling of the underlying liquid steelmaking processes enhances planning, scheduling and execution functions of a melt shop production management system. The presented solution also comprises a hybrid prediction model for scrap attributes such as chemical analysis including contents of tramp elements, metallic yield and specific electric energy consumption, which in general have high uncertainties. This scrap characterization model increases the accuracy of the optimization calculations and thereby reduces the costs of resulting raw material mixes as well as the number of out-of-specification heats.

Speaker: Dr Martin Schlautmann (PSI Software SE)

28 Filter cake by-product from pickling line transformation into a valuable product to recover the metallcs for EAF steelmaking process.

Lhoist together with a steelmaking company based in UK developed a new product to be recycled into the EAF process. This new product is based on the transformation of Filter cake by_product coming from the pickling line process containing valuable metallics. Indeed such by-product is mainly landfilled over the world. Three main reasons may explain : the water content is very high > 45%, the dry product is very fine D50 ~20 µm, and its contains an important dosage of CaF2. Transforming thus Filter cake to be recycled into an EAF process is mainly motivated by the metallic recovery and the avoidance of the landfilling. This paper will explain first all challenges to be circumvented. In a second part the results of the feasibility tests at lab scale and pilot scale will be discussed. In the last part the successful results of a 40t trial at industrial scale will be presented. All positive and negative technical results will be discussed. This 40t trial opens the door to a circular business solution to be extended to other geographies.

Speaker: eric perrin (LHOIST Innovation)

29 Study on the Effect of Direct Reduced Iron on the Nitrogen Content in Electric Arc Furnace Steelmaking

As a typical harmful element in steel, the presence of nitrogen can seriously affect the performance of steel materials. Restricted by raw materials, equipment and process conditions, the nitrogen content of electric furnace steelmaking is high, which cannot meet the quality requirements of high-grade sheets such as automobile sheet and silicon steel. The use of direct reduced iron to control the nitrogen content in electric furnace steelmaking is a feasible technical route. In this study, a pilot experiment was carried out in a 10t electric furnace using direct reduced iron (HBI in this study), and the results showed that: for the heats without hot heel, the total HBI ratio increases to 40%, and the nitrogen content of steel can reach 40 ppm or less when it is completely melted, and for the heats with hot heel, the nitrogen content of steel when it is completely melted is more obvious with the change of the total HBI ratio, and it can reach nearly 35 ppm when the total HBI ratio increases to more than 30%. In the experimental process with the oxygen inject, the carbon content of steel continues to decrease, while the nitrogen content of steel shows a trend of decreasing and then increasing, the inflection point occurs in the carbon content of 0.20% to 0.56%, indicating that under the process conditions of this equipment, for the carbon content of more than 0.56%, oxygen injection decarbonization will be effective in denitrogenation, and when the carbon content is less than 0.20%, attention should be paid to avoiding the increase of nitrogen content.

Speaker: Dr Zhao-ping Chen (Baoshan Iron & Steel Co., Ltd..)

30 Optimization of scrap mix in EAF steelmaking

A numerical model for the estimation of main variables in Electric steelmaking is presented. The multiplicity of phenomena occurring in the EAF together with the huge number of variables and their complex interaction, prevents the development of a reliable online application able to take direct action on the process. An alternative approach in which the overall average performance of the EAF after a period (a week, a month) is considered instead. By performing mass/energy balances over a certain period, this strategy allows to estimate how much consumables (electrical energy, electrodes, oxygen, fluxes) are required to operate the furnace for a given scrap mix and target liquid steel production. In this way the transformation cost of the material loaded in the furnace can be computed. Particularly, the impact of adding a new material in the overall cost can be established.

The model has been tuned to represent the six EAFs of Tenaris and is used by technologists, industrial planning staff and cost analysts of five different steel shops. It was implemented in a web application, making it available for all users.

Speaker: Sergio Pablo Ferro

31 Bucket Loading and Scrap Yard Logistics Simulation - Optimizing Material Flow and Enhancing Efficiency

This paper synthesizes five years of simulations across diverse scrap yards, demonstrating how discrete event simulation enhances material flow optimization. The presentation will distill five key lessons, addressing common pitfalls in scrap yard modeling, optimizing scrap pile locations, comparing scrap manipulators, improving bucket handling time and integrating new processing plants. The findings offer a practical road map for steel plants to leverage state-of-the-art simulations, resulting in demonstrable improvements in production efficiency.

Speaker: Paul Uhl-Hädicke

Rolling Mill Technology & Process Optimization

3.1.1

Convener: Dr Ettore Anelli (Franchini Acciai SpA)

32 Work Roll Cooling Optimization

This paper presents an optimization study of a hot strip mill first finishing stand (F1) top work roll cooling system, which was done in cooperation between Danieli (Buttrio, Italy) and Heat Transfer and Fluid Flow Laboratory (BUT Brno, Czech Republic). The target of the study was to decrease water consumption by more than 25% on the top work roll, maintaining the same (or better) cooling efficiency.
This study was divided into three phases. Phase 1 focused on analyzing the current cooling configuration using laboratory measurements with a unique rotary stand embedded with temperature sensors. The experimental setup involved heating a test segment to 320°C and cooling it to ambient temperature, collecting heat transfer coefficient data for different roll diameters and water pressures.
Phase 2 was focused on the study of several parameters, such as water pressure, nozzle size and positions, spray distance, etc., on the heat transfer coefficient. Obtained data were evaluated and two optimized cooling systems were proposed: one with two cooling headers and the other with three, both on the top roll exit side. Detailed experiments comparing the original and new configurations under various conditions demonstrated the possibility of significant water savings and improved cooling efficiency, with the first configuration achieving 34% water savings and the second up to 46%.
The third phase was done by Danieli by designing and installing the new cooling system in a finishing stand of a continuous hot strip mill. The validation of the new cooling configuration required the implementation of a work rolls temperature measure system in line for continuous rolling mill to evaluate the cooling performances. A 40% reduction in the cooling water flow rate has been achieved, maintaining the work rolls temperature during rolling unchanged.

Speaker: Milan Hnizdil (Brno University of Technology, Heat transfer and fluid flow laboratory, Faculty of Mechanical Engineering)

33 Optimisation of CSP hot rolled structured steels based on Nb micro-alloying to reduce costs and GWP

All demanding modern applications such as structural, energy and automotive, require steels with an increasingly high level of strength and ductility whilst retaining good cost competitiveness as well as fulfilling ever demanding emission levels. Structural steels have traditionally focused on obtaining strength via C and Mn with some mini-mill producers utilising V micro-alloying to achieve properties. But, more stringent sustainability credentials and pressure to reduce costs as well as improved productivity are factors that are motivating producers to utilise low to medium C chemistries with reduced Mn and V where the benefits to product quality, processability and especially costs are paramount.

Speaker: Paul Lalley (CBMM)

34 Real-Time Work Hardening Evaluation for Optimizing Hot Rolling Schedules and Power Demand in HSLA Steel Production

Abstract
The hot rolling mill power requirement depends on several factors, including the material's properties, strain and strain rate schedule, rolling temperature, microstructure evolution and roll-workpiece friction condition. On the other side, the thermomechanical process relies on precisely controlled softening and hardening phenomena to achieve the desired microstructure and tensile properties after rolling and final cooling. In order to optimize both needs (steel quality and energy cost) a novel incremental plasticity approach is introduced to optimize contemporarily the power requirements and the microstructure evolution during hot rolling process. Both deformation energy and microstructure changes are related to the work hardening of workpiece in the roll bite, according with a first-order differential equation, dσ/dε = Ωσ, where the hardening function Ω is independent of stress and is influenced by rolling pass geometry, material properties and roll-workpiece friction condition. The proposed approach allows for the calculation of drive-power requirements in terms of cumulative deformation energy for each rolling pass and enables the prediction of the metallurgical capability of an existing mill to process products of varying dimensions, steel grades, or rolling conditions. This not only to predict steady-state power and torque requirements, but also to estimate the peak values developed under transient conditions. The results of this approach to hot rolling plate mill for HSLA steel grades were quite positive, demonstrating significant potential to achieve optimal microstructure and tensile properties while minimizing both mill power and torque.

Speaker: Dr Alessandro Ferraiuolo (Marcegaglia Steel)

35 Advanced Load Sharing Control for Roller Straightening of Long Products

Hot-rolled long products such as beams, bars, and rails are curved after cooling. Roller straightening aligns these curved long products by passing them between staggered rollers, inducing controlled, repeated elastic-plastic bending. SMS group technology for roller straightening machines is the CRS® Compact Roller Straightener, typically characterized by nine, individually driven straightening rollers.
To optimize the utilization of the system, achieve an even and controlled distribution of the total load across the drive rollers, avoid over-dimensioning of the drives, and protect the machinery from overload, the required drive torque is distributed specifically across the drives using a control system.

A new, optimized LSC has been developed by interdisciplinary cooperation within the SMS group. This new LSC features the elimination of master-slave operation, as a result it enables control when not all rolls are in operation during pulling in and out. It is independent of the process parameters (roll diameter, roll adjustment) and redistributes the total drive torque to the single drives according to a predefined pattern.

Initial functional tests were conducted on forces and drive torques calculated with the aid of finite element (FE) simulations of the roller straightening processes and with available measurements. But the successful implementation of the newly developed LSC in three industrial CRS® in the fields of railway rail, medium and heavy section production conclusively demonstrates its effectiveness.

In a following phase the quasi-static FE-model is coupled with a subsequent dynamic model in MatLab-Simulink accounting for the systems inertia. Coupling this combined model set-up with the LSC reproduces the time dependent redistribution drive torques and product’s velocity.

The new optimized LSC offers benefits such as reduced total drive capacity, decreased roll wear, reduced experimental effort during commissioning and improvement of product quality. Furthermore, it can be implemented on cantilever and vertical straightening machines as well.

Speaker: Koos Van Putten (SMS group)

36 Optimisation of roll cooling and descaling processes at Erdemir HSM#2

The Hot Strip Mill # 2 of Erdemir started operation in 1978. Since the startup, two major revamps were conducted in 1995 and 2007.

Potential for further optimizations was expected in the roll cooling header design comprising a wide range of different nozzle types including very small nozzles, which are prone to clogging. As a result, the strip thickness across the width was affected and the roll surface quality was poor. The efficiency of the roll cooling system had to be checked after HSS type rolls were in operation. Moreover, a study how to improve the descaling efficiency was also included.

Lechler investigated both, the roll cooling and descaling systems aiming for an optimization of the existing processes utilizing the available resources and avoiding major modifications of the existing systems. Based on detailed technical proposals modifications were made to both systems.

A thermal roll cooling study has was carried out evaluating the potential for increased efficiency utilizing the existing cooling water capacities. A revised roll cooling nozzle layout redistributing the cooling water would reduce the work roll surface temperatures, minimize defects, and extend the lifetime of the work rolls.

Simulations on the existing descaling operations were conducted benchmarking the existing descaling performance. Based on these result revised descaling nozzle layouts have been proposed in order to increase the efficiency utilizing existing pump capacities. A significantly improved descaling performance in combination with reduced energy costs for descaling operations were achieved.

As a result of these optimizations the productivity of the hot strip mill was increased by reducing roll cooling problems (roll wear and surface quality problems, preventing nozzle clogging), cost savings have been achieved by decreasing water flow in descale headers. The product quality was increased by decreasing the scale and roll surface quality problems.

Speaker: Robert Wolff

37 X-Pact® Total Roll Gap Control (TRC®): Improvement of yield and reduction of non-productive time at CCM® Marcegaglia

A frequent source of yield losses, especially for reversing cold mills, are the unrolled head and tail ends of the strip. The conventional threading method without reduction at the strip head end results in a considerable loss of yield of 1.5 to 3 percent or more of the overall production of the plant.

At the same time, preparation and threading of the strip head-end are time-consuming and require the cooperation of experienced operators. Depending on the type of rolling mill, production capacities and product mix, this procedure must be carried out more than 10,000 times per year. The use of the conventional threading method leads to production bottlenecks and thus increases the operating costs further.
The X-Pact® Total Roll Gap Control (TRC®) is an assistance system, which aims to ensure stable rolling directly from the strip head end while at the same time reducing off-gauge and off-flatness lengths at strip head and tail end. In addition, it ensures an improved, from the operator independent threading process.
SMS implemented the TRC® in the automation system of the two-stand reversing cold rolling mill (CCM®) Marcegaglia in order to achieve minimum off-gauge weights. The respective off-gauge weight of the finished strips and the non-productive times resulting during rolling were then calculated based on the operating results of the plant.

A comparison of the results with active TRC® versus without TRC® shows the advantage achieved with regard to the reduction of the off-gauge weights at the head and tail ends of the finished strips. At the same time, the use of TRC® achieves a significant reduction in non-productive rolling times.

In summary, the use of the TRC® at the CCM® Marcegaglia underlines the potential for improvement in overall production while at the same time reducing the operating costs of a cold rolling mill.

Speaker: Mr Markus Koch (SMS group)

Surface Technologies

4.3.1

38 High temperature oxidation in steel processing under different process conditions, atmospheres and rising levels on tramp elements

The ongoing transformation to more sustainable production routes of the European steel industry is one of the major challenges in the upcoming years and is accompanied by a number of changes; 1) the use of a different raw material mix (more and lower scrap qualities), 2) the introduction of new processes or process combinations (e.g. direct casting and rolling processes) and 3) the use of alternative energy sources for reheating before hot rolling (e.g. reheating by hydrogen combustion or electrical reheating). These changes go hand in hand with a significant reduction of the CO2 footprint and with a different process control and expected product quality. Oxidation processes, which are unavoidable in continuous casting and further hot processing of steel, may have a negative impact on the surface quality and must be reconsidered with regards to this transformation.

In view of the changes, the understanding of the mechanisms behind high-temperature oxidation is of great importance: The interaction between external oxidation and internal oxidation, decarburization and liquid metal infiltration of grain boundaries will become essential for the retention of product quality under new operating conditions. These effects are influenced by parameters such as oxidation time, temperature, atmosphere and the chemical composition of the steel and the level of undesirable tramp elements such as Cu, Sn and Ni, which do not oxidize but accumulate at the bulk/scale interface or along surface-near grain boundaries.

To address these newly arising research questions a lab test setup was established: Utilizing Simultaneous-Thermal-Analysis in combination with various gas atmospheres (CO2, H2O, N2, O2, Ar), a precise investigation of surface oxidation phenomena in a wide variety of metallurgical processes became possible. The present work addresses selected results of continuous casting and reheating operations, where various process conditions were studied to accompany the transformation and make statements about new scenarios.

Speaker: Peter Presoly (Montanuniversität Leoben)

39 ON-LINE STEEL SURFACE CONTAMINATION MONITORING WITH LIBS-BASED SENSOR

Sarclad and CRM Group have successfully developed a new on-line sensor for steel strip contamination. The system utilizes laser-induced breakdown spectroscopy to give a continuous and real-time assessment of the contamination levels post-cleaning on a typical steel strip processing line.
Critically, this is the first system available that can distinguish between surface carbon and iron fines contamination with quantitative data. This will enable the highest product quality alongside optimized core cleaning section parameters, like electrolysis current level, degreasing bath concentration or brushes pressure, to give the greatest process efficiency.
This paper describes the results obtained by this sensor in industrial demonstration trials on commercial continuous galvanising lines.

Keywords: laser induced breakdown spectroscopy, LIBS, surface contamination, galvanisation, iron fines, carbon pollution, online cleanliness.

Speaker: David Egner (SARCLAD)

40 Energy- and Space-Saving Electrolytic Cleaning with SMS group Pulse Nozzle Technology

SMS group Pulse Nozzle technology reduces the energy consumption of the electrolytic cleaning section in strip processing lines by up to 90-95 %. The novelty of the process lies within the application of alternating current and its efficient cleaning properties. Instead of submerging the strip and simultaneously applying high currents, the Pulse Nozzle contacts the strip surface with continuously flushing fluid, using less than 5 % of the current. Therefore, the rectifier capacity can be 95% lower with the new Pulse Nozzle system, saving CAPEX and OPEX. Moreover, friction from submerging in fluid and wandering currents are eliminated with the new electrolytic cleaning Pulse Nozzle. The production of H2 is significantly reduced by applying alternating current instead of direct current.

The Pulse Nozzle has been thoroughly tested in a continuous annealing line producing tin plate steel materials. The results show that one pair of Pulse Nozzles can replace one traditional electrolytic cleaning tank. Multiple production coils have been processed using the new Pulse Nozzle without any constraints regarding quality after annealing and coating in ETL.

Noteworthy is that the Pulse Nozzle System can be installed in existing processing lines. Depending on the line design, even a switching between cleaning systems can be achieved within one hour after initial installation.

The new development not only allows energy saving during cleaning, but it also reduces the space requirements, requires smaller tanks and circulation, and most substantial a reduced power supply.
Overall, the Pulse Nozzle system with its space and energy saving properties is a worthwhile investment.

Speaker: Dr Hanna Wolff (SMS group)

41 On-line laser cleaning of skin pass rolls

This abstract is related to the EU RFCS project OLACSKIN, focalised on the removal of zinc stains and zinc fouling by laser cleaning at the skin-pass mill.
This presentation will be focused on the characterisation of the work rolls contamination and the first results obtained on zinc removing by laser.
If successful, this project will result in a yearly reduction of: 30.000 m³ of wastewater, 40 m³ of detergent, and a significant amount of energy (about 18 kW continuously for high-pressure pumps).
In addition to significantly reduces environmental impact, offering a more sustainable and eco-friendly skin-pass operation, it will also open up new opportunities into 'dry skin-pass rolling' and could give a solution as substitute for CrVI coating of rolls.

Speaker: Gaétan Symens (CRM Group)

42 Oiling of Steel Strip: A New, Intelligent Oiling Machine Combines Electrostatic Oiling With High-Precision Oil Film Measurement, Ensuring Higher Process Security and Lower Oil Consumption

The newly developed combination of oiling machine, smoothing roller and online oilfilm measurement system ensures uniform oil application on metal strips while minimizing oil consumption. Integrated with an inline oil film measurement system, it promptly detects oiling issues like overoiling or dry stripes, allowing operators to take immediate action.A key innovation is the smoothing roller, which applies consistent pressure across the entire strip width, ensuring uniform oil distribution. This roller compensates for force variations, maintaining pressure accuracy within just a few percent across the strip width. The data integration enhances material efficiency and product quality. The machine’s reduced oil usage supports sustainable production of CO2-neutral steel coils. Its compact, modular design enables easy integration into existing production lines and adaptability to future needs, providing plant operators the flexibility to continuously optimize processes without significant capital investment.

Speaker: Martin Fieweger (AMEPA GmbH)

43 Plasma Nitriding of Vanadium-Alloyed Air-Hardening Ductile Steels

Steel components exposed to dynamic loads are prone to wear and oxidation. Nitriding is a thermomechanical treatment employed to overcome these issues. The significant enhancement in the properties of steel components following nitriding is mainly attributed to increased surface hardness, the development of internal stresses, and chemical modifications within the treated zone. Vanadium as an alloying element in steels can significantly influence the plasma nitriding process and its outcomes. The presence of vanadium can enhance the overall nitriding performance of the material.

A recent innovation introduces a new class of martensitic steels that achieve their final properties through air cooling directly from the forging heat. These air-hardening ductile (AHD) forging steels, alloyed with approximately 4 wt.% manganese, develop a uniform martensitic microstructure without quenching and tempering, significantly lowering CO₂ emissions. With the first commercial melts of these steels now available, interest in their performance across various applications is increasing.

This study focuses on the role of vanadium in the plasma nitriding behavior of AHD steels, particularly its influence on hardness and phase formation. Vanadium-alloyed AHD steels were subjected to plasma nitriding at various temperatures, and their microstructural evolution and mechanical properties were systematically analyzed. Hardness measurements using micro-Vickers indentation revealed that vanadium-containing compositions exhibited higher hardness compared to vanadium-free counterparts. Phase analysis conducted via X-ray Diffraction (XRD) indicated variations in nitride formation, while microstructural characterization using Scanning Electron Microscopy (SEM) and Light Optical Microscopy (LOM) provided insights into surface morphology and diffusion depth. The findings highlight the potential of vanadium as an important alloying element in the nitriding performance of AHD steels.

Speaker: Dr Rolf Schmidt (VantageAlloys AG)

Waste Processing & Byproduct Utilization

5.3.2

44 Technical Considerations in the Design of Capture Systems to Control Fugitive Releases in Ironmaking and Steelmaking

The adequate design of ventilation systems for the capture of hot, fugitive releases from ironmaking and steelmaking operations requires good estimation of fume release rates and temperatures, whether it be for short term operations such as scrap charging into an EAF, or for operations that can be adequately characterized as continuous releases, such as melting and refining. There are various methods and techniques used to estimate release rates, including empirical tools such as the Hemeon & EPA methods, plume photography and video analysis, scaled-down physical models, as well as CFD based simulation methods. This paper describes some of the assumptions involved and comparisons between these various methods, and how they can impact the sizing of the capture system (i.e., canopy hood design, ventilation exhaust flow specification, etc.). Some key technical considerations are highlighted when using these various methods, which can greatly influence the design of the capture system. These include, as examples, 1) paying careful attention to the height of a developing, buoyant plume versus a fully developed plume that most empirical methods are based on, 2) the location above the emissions source where plume photography is taken and used for plume flow estimation, 3) a consideration for the impact that obstructions (such as crane rails, scrap buckets, etc.) and wind cross-drafts can have on the plume deflection and movement. This paper demonstrates how CFD modeling, which is a first principles-based method, is better able to predict more realistic plume behavior under the conditions, and the resulting impact on the design of the fume capture systems.

Speaker: Mr Wayde Johnson (Hatch Ltd.)

45 Sensor solutions for online analysis of post-consumer scrap

The PURESCRAP project develops sensor solutions for analysis of post-consumer scrap with the aim to enable increased use of low-quality scrap grades (post-consumer scrap) for the steel industry. Sensor stations are built for the two separate processing chains of heavy (cut) and shredded scrap. It includes sensors for chemical analysis, size metrics and object recognition. The sensor stations will be used both for better understanding of the scrap processing operation at the recycler as well as providing an accurate chemical analysis of individual scrap batches to be used by the steelworks.

Forecasts reveal that the crude steel demand will continue to rise and at the same time the availability of post-consumer scrap will increase even more. The uncertainty of the level of tramp elements in the scrap limits is use for steelmaking. If the composition of the scrap is known these tramp- or alloying elements in the scrap can instead be used as a resource and the total amount of scrap in the heat can be maximised.

In the PURESCRAP project, the sensor chain comprises a camera, LiDAR (Laser imaging, detection, and ranging), LIBS (laser-induced breakdown spectroscopy), and XRF (X-ray fluorescence). The sensors are coupled by a comprehensive information and communication technology (ICT) network. The combined methods are installed and tested at the Swedish recycling plant of Stena Recycling. The scrap, which is processed, is further sent to partners voestalpine and SSAB for melting and reference analysis of the chemical composition of the scrap. To validate the efficiency of the PURESCRAP sensor stations, limits for nonferrous tramp elements (e.g., Cu, Ni, Mo and Sn) have been specified.

Speaker: Dr Jonas Petersson (Swerim AB)

12:50 Lunch

46 The Steel Industry – Setting the Standard for the Twin Transition

The steel industry is integral to society, supplying the necessary materials for infrastructure and technologies, from renewable energy systems to the electrification of transportation. As a key part of our world, the steel industry is not immune to the dramatic transformations impacting multiple sectors, namely sustainable and digital transformations, the “twin transition.” Today, the steel industry alone is responsible for nearly 10% of global carbon emissions. Sustainable production methods, including the global adoption of direct reduction technologies to replace the carbon-intensive blast furnace process and increased focus on electric arc furnace-based steel production, reflect changes across heavy industry as the path forward in the “twin transition.” Simultaneously, new and existing systems are achieving new levels of efficiency and production quality thanks to advanced digital systems. With artificial intelligence driving technological advancement, automation systems combine with the latest data analytics and monitoring to realize a fully autonomous operation capability.

Primetals Technologies is bringing the steel industry through these transformations via two intertwined concepts: the sustainable steel plant and the fully autonomous plant. The sustainable steel plant produces “green steel” by leveraging carbon direct avoidance technologies, such as hydrogen-based direct reduction and electric arc furnaces powered by renewable energy sources. Moreover, additional technologies, such as dedusting systems, capture and recycle unused raw materials. In parallel, the fully autonomous plant integrates sensors, robotics, and virtual tools to simulate, optimize, and adjust production routes to meet ever-changing market demands for high-quality steel. With decades of experience in the industry, the experts and specialists of Primetals Technologies are charting the path toward the future of steel production, and producers worldwide are laying the foundation for groundbreaking projects. The steel industry is a frontrunner for global heavy industry, setting the standard in the “twin transition,” transforming existing production routes and investing in sustainable digital innovations.

Speaker: Dr Alexander Fleischanderl

14:20 Time to change rooms

Continuous Casting Process Fundamentals & Defect Analysis

2.3.1

Convener: Riccardo Carli (Prosimet SpA)

47 The Impact of Cu, Sn, and Ni on Surface Cracking in Continuous Casting

Within the ongoing transformation of the steel industry towards lower CO2 emissions the share of steel produced via electric arc furnace will be rising. Depending on the input material (DRI/HBI, scrap, …) the infiltration of undesirable tramp elements such as Cu, Sn and (Ni) may be unavoidable and due to their special properties removal from the liquid steel is hardly possible.
Defining the impact of Cu, Sn and Ni on the susceptibility to surface crack formation in continuous casting under near-process conditions presents a significant challenge, as it requires testing under oxidizing conditions. Recent publications have shown the superior possibilities of In-situ Material Characterization by Bending test (IMC-B) in investigating oxidation-related phenomena affecting surface crack formation. The experimental procedure involves solidification of the samples in a mold to achieve a microstructure similar to continuous casting, followed by controlled cooling in an air/water vapor atmosphere and deformation in an isothermal three-point bending test. In this study, a medium carbon construction steel was examined both with and without Cu, Sn, and Ni. The contents of Cu and Sn were set at 0.15 wt.% and 0.01 wt.%, reflecting the expected future levels of these elements in steel production, whereas Ni was added at 0.25 wt.%.
The results clearly indicate an increase in crack formation for the addition of Cu and Sn particularly in the temperature range of 900 to 1000 °C. The rise in crack formation is attributed to the presence of low melting Cu-rich phases at the grain boundaries. In contrast, a bending temperature of 1100 °C was found to be uncritical. The addition of Ni effectively counteracts the crack formation caused by Cu and Sn, resulting in conditions similar to the base steel without any tramp elements.

Speaker: Georg Gaiser (Chair of Ferrous Metallurgy, Montanuniversität Leoben)

48 Reduction of emissions at casters cooling chamber.

The steel industry has been undergoing significant transformations over the years, particularly with regards to environmental regulations. Environmental authorities have continuously raised emission limits for the entire sector. This is putting a focus on previously overlooked emission points, such as the caster cooling chamber. Lechler, a renowned nozzle and demister company, is developing innovative solutions to reduce dust emissions.

Lechler has been designing and successfully implementing state-of-the-art, simple but effective systems to reduce dust emissions for many years. A prime example of these efforts are the systems implemented after the cooling chambers at casters. By introducing customized dust reduction systems, Lechler achieved a remarkable improvement in emissions. Solid Emission levels fell from around approx. 20 mg/Nm³ to 0,82 mg/Nm³ and overall, from approx. 80 mg/Nm³ to 5 mg/Nm³ at the steam stacks, underlining the effectiveness of the measures.
According to the actual BREF, the emissions are set to a maximum of 5 mg/Nm³ at EAF, almost all existing plants have far too high emissions levels.

Recognizing the complexity of the issue, Lechler's solution can be integrated seamless into existing operations, offering a practical solution reducing dust emissions from cutting machines. By applying their expertise in nozzle technology and demister solutions, Lechler has paved the way for sustainable practices in the steel industry.

Moving forward, it will be essential for stakeholders within the steel industry to embrace innovative solutions. By prioritizing environmental sustainability, companies can not only comply with legal standards but also promote a culture of responsible manufacturing for future generations.

Speaker: Arndt Wilhelmi (Lechler GmbH)

49 Characteristics and Control of Oxide–Sulfide Complex Inclusions in D2 High-Speed Railway Wheel Steel

The hard oxides wrapped by the plastic (Mn,Ca)S sulfides can effectively reduce the harmful effects of oxides on D2 high-speed railway wheel steel. An analysis of the composition characteristics of complex inclusions reveals that 1 to 2 μm CaO·6Al2O3 (CA6) and CaO·2Al2O3 (CA2) serve as core, promoting the growth of (Mn,Ca)S, which contains 5 to 20 mass pct CaS and 80 to 95 mass pct MnS. This results in the formation of Al2O3–CaO + (Mn,Ca)S complex inclusions. These complex inclusions with specific composition can deform in harmony with the steel matrix under the external forces, making them ideal complex inclusions for wheel steel. To quantitatively analyze the formation process and control methods of complex inclusions, a mathematical model is established to describe the inclusion formation during the cooling and solidification of molten steel. The results indicate that CA6 and CA2 are mainly formed during cooling and solidification, with their sizes remaining under 2 μm. These oxides serve as the cores to promote the formation of (Mn,Ca)S in the later stages of solidification. To increase the formation of such complex inclusions and reduce the appearance of large-sized oxides, it is vital to control the contents of Al, Ca and O to 0.011 to 0.016 mass pct, 6 to 8 mass ppm and 8 to 10 mass ppm, respectively.

Speaker: Dr Daohua Bao (State Key Laboratory of Advanced Metallurgy, University of Science and Technolog)

Direct Reduction Process Optimization

1.4.2

50 Improving Direct Reduction Operation efficiency through Roller Screen technology

Steel production through the Direct Reduction (DR) route presents a more sustainable alternative to conventional blast furnace processes. However, the generation of fines during raw material handling and intermediate processing stages creates significant operational challenges. These include decreased process efficiency, reduced plant throughput, increased energy consumption, and diminished product quality in DR modules and Electric Arc Furnaces (EAF) operations.
Roller screens, a well-established technology in iron ore pelletizing operations, effectively minimize the fines content in the pellets charge compared to traditional vibrating screens. The benefits of using a lower fines content in the DR modules is translated in a better bed permeability, leading to improved gas flow and metallization rates, reduction of intermediate processes such as briquetting and supplementary screening, reduced downtime and maintenance requirements due to the robust design of roller screens.
In EAF shafts, the reduction of fines content using roller screens may provide additional operational advantages, such as a decrease on pellet breakage, resulting in lower slag formation and improved melting efficiency, reduced electrode consumption and lower specific energy requirements, enhancing the overall process efficiency and cost-effectiveness.
This paper examines the adoption of roller screen technology as a replacement for traditional vibrating screens within the DR process, exploring the screening performance and fines content achieved in industrial trials and evaluating its effects on both Direct Reduced (DR) shafts and Electric Arc Furnace (EAF) operations.

Speaker: Alexandre Gonçalves Andrade (Metal7 Inc.)

51 Pellet reducibility index management range for direct reduction plant

Blast furnace is a process that reduces iron ore to obtain pig iron. Due to its high efficiency, it has been adopted as a major facility. As a result, not only have various technologies been developed and researched, but evaluation methods have also been established to optimize the raw materials used for efficient plant operation. Utilizing these evaluation methods, raw material management standards optimized for the facility characteristics have been established. However, the blast furnace emits excessive greenhouse gases.
As global regulations on greenhouse gas emissions become increasingly stringent, the need to reduce emissions in various industries is growing. In the steel industry, direct reduction plants are being focused for carbon neutrality. As they emit fewer greenhouse gases compared to the blast furnace and can be more easily transitioned to hydrogen‐based steelmaking. Representative DRI production facilities include MIDREX and ENERGIRON, and global steel companies are currently planning to introduce these systems.
Since these DRI production facilities cannot undergo additional reduction processes after the reduction zone, raw materials must be selected that can secure the target reduction ratio in the furnace. In shaft furnaces, the process involves reducing pellets using high‐temperature reducing gas, necessitating the establishment of operational standards that reflect the influence of gas composition and temperature in the reduction zone. Therefore, this study aims to assess the validity of the current MIDREX pellet reducibility evaluation standard, improve it, and determine management ranges for stable operation using a new reducibility evaluation method.
In this study, equipment was configured to simulate the main reduction zone within the shaft, and temperature, reducing gas flow rate, gas composition, and reaction time were set to evaluate pellet reducibility. Additionally, a DRI reducibility management standard was established to ensure the molten quality of DRI. We derived the usage priority groups for the pellets.

Speaker: Dong Soo Lee

52 Hot DRI Material Gate – A smart product for green steelmaking in a digitalized future

This paper presents the development and implementation of a new material gate for charging of hot DRI bulk material in melters downstream of direct reduction plants or hot pellet materials in shaft furnaces or smelters. Developed and tested over a two-year period, this material gate displays innovative solutions regarding mechanical design, serviceability, and condition monitoring, creating a future-proof solution for green steelmaking.

The material gate’s mechanical design enables low-effort maintenance, resulting in an important downtime reduction. Compared to existing solutions, a threefold size reduction enables a more flexible plant integration and lower plant height, resulting in significant cost savings. Thermal simulations and materials research ensure thermal resistance, efficiency, reduced wear, and, most importantly, worker safety. Extensive particle flow simulations enabled a data-based decision making process regarding key dimensional parameters of the DN400 gate, improving overall material throughput and enhancing the understanding of the material flow behavior.

Its condition monitoring concept makes this equipment an intelligent and future-proof product in our portfolio. A multitude of sensors is keeping track of its current state, functionalities, and potential need for maintenance. This supervision reduces plant downtime significantly and makes the equipment a smart solution for digitalized plants.

Several tests ensure great customer experience from the first project on. Small-scale experiments allowed analyzing the sticking and flowing behavior of DRI pellets. A full-scale prototype was successfully tested under realistic conditions with hot DRI pellets at 700 °C, confirming the design choices and collecting valuable data to validate the simulations.

After the extensive developing and testing process, the gained experience allowed further optimizations of the material gate, before launching the first series production for a customer direct reduction plant. This device is perfectly suited for the next generation of green steelmaking plants producing hot DRI, given its unique combination of reliability, maintainability, and condition monitoring.

Speaker: Mr Jérôme De Matteis (SMS group)

53 Key measurement technologies for direct reduction ironmaking

The direct reduction process is of rising importance in ironmaking in the frame of the decarbonization effort of the steel industry. While these are known and elaborated processes, they are evolving due to the use of hydrogen, the use of lower-grade raw materials, and a size increase to achieve the required production rate. These changes require innovative process control.

The process efficiency and productivity are influenced by the residence time of the iron ore and the volumetric flow rate of the reducing gas. It is evaluated through the oxidation rate of the reducing gases, and the solid product’s metallization degree. Today, the gas composition is determined by an extractive measurement, which is slow and complex. The metallization degree is measured in an offline laboratory analysis of material samples, thereby being both discontinuous and with a time delay.

This work presents novel online and in-situ measurement technologies for both the metallization degree and the gas utilization, enabling continuous monitoring with response times within few seconds. The measurement precision of the technologies has been tested and confirmed.

The metallization degree sensor identifies the ferrous components via the magnetic permeability and temperature. It has been validated with real material and compared to alternative technologies including XRD and LIBS methods.

The gas utilization is monitored with a laser-based in-situ spectrometer measuring all involved gas types, including the hydrogen, nitrogen, and water content. It is important to note that H₂O is a process gas and must be measured, which is not possible with conventional techniques in conjunction with high H₂ content. The analyzer concept was evaluated in a university laboratory setup and at a blast furnace.

The measurement technologies can be efficiently integrated into the direct reduction process by using proven probe solutions.

Speaker: Mr Filipe Rodrigues (TMT Luxembourg)

54 Carbothermic reduction of hot rolling sludge by rice husk char with microwave heating

The scale generated in the hot rolling process is a high-grade iron source. Fine scales are separated in a thickener and discharged as sludge in a slurry state, and they are difficult to use. This study focused on the sludge recycling through carbothermic reduction using microwave heating. Microwave heating occurs when an object absorbs microwaves. Compared to conductive heat transfer, microwave heating allows for internal heating, making it effective for heating fine powders with low thermal conductivity. To achieve carbon neutrality, the carbothermic reduction behavior was investigated using biomass-derived carbon.
For the experiment, the industrial sludge, rice husk char as biomass and reagent-grade graphite were used. The sludge had a composition of T. Fe = 64.1 wt% and FeO = 36.2 wt%. The biomass was obtained by pyrolyzing rice husks at 500°C, containing 43.2 wt% carbon and 47.7% SiO₂ as the main impurity. The biomass or graphite and sludge were mixed in a mol ratio the carbon and oxygen content in the sludge matched C/O = 1. Microwave heating was carried out with 2.45GHz multi-mode iraddiation with magnetron under a nitrogen atmosphere. The total heating time was 20 minutes, with a maximum output intensity of 1050W. The samples were heated from room temperature to degree C and then maintained at that temperature. After heating, the formation of metallic iron was confirmed in both samples. During microwave heating, the sample using biomass took longer to stabilize at 1200 degree C compared to the graphite. It seems due to the SiO₂ in the biomass not absorbing microwaves. SEM-EDS analysis on the reduced samples confirmed the presence of metallic iron and residual FeO in both samples. Additionally, in the biomass sample, large amount of silicate slag containing iron oxides was observed.

Speaker: Mr Tshubasa Tokunaga (Kyushu University, school of engineering)

EAF Design & Power Supply Optimization

2.2.2

Convener: Carlo Mapelli (Dipartimento di Meccanica - Politecnico di Milano)

55 Improved EAF performance by optimized high current system design

Badische Stahl-Engineering GmbH developed and applies the most sophisticated simulation tool available in steel industry today: the Farschtschi Network Method (FNM). With this unique simulation tool the optimal design of the EAF high current system is feasible in terms of electrical symmetry, forces on high current cables, torques on mast system and power input performance. The capability of very accurately simulating the existing situation and comparing it to a new design is crucial for EAF performance. As an application example the revamping approach of Badische Stahlwerke GmbH is presented. BSW plans to modernize the EAF #2 in a stepwise process by first exchanging the high current and hydraulic system and only much later the complete furnace gantry and shell. The challenge is to predict the performance of the first step modification that will operate with the old, mechanically weak furnace mast-gantry-system and thus justify if the first revamping step alone is benefitial or not. Concretely, the torques on the masts need to be known for the new design to see if the mechanical stability improves (system excitation by magnetic forces and torques).
To show more benefits of FNM, a comparison between a non-sophisticated design of a high current system and a FNM-simulated modification is presented for a large stainless steel EAF. There the very limited arc coverage by slag on flat bath operation requires the best electrical symmetry of the high current system to avoid refractory wear. With FNM the required modification of the asymmetric system can precisely be simulated. Other furnace manufacturers are not capable to design the optimal symmetry by lack of accurate simulation tools.
BSE also offers the optimization of high current systems of „Consteel“, „Quantum“ and as well of DC furnaces (to reduce arc deflection).

Speaker: Dirk Riedinger (Badische Stahl-Engineering GmbH)

56 Direct Feed Power Supply to enhance power quality and EAF KPI

Decarbonizing steelmaking is one of the greatest challenges facing our industry today. Electrifying steel production is a pivotal step in reducing CO2 emissions. Over the coming years, the installed base of high-power EAF is expected to grow significantly, which will affect power quality but also EAF performances. To address these challenges, GE Vernova has developed an innovative solution.
The Direct Feed system, connects directly to the grid, enabling precise and highly stable electrode current regulation.
Design of the Direct Feed system will be presented with performance results derived from simulations and on-site measurements. Key outcomes, including improvements in EAF flicker reduction and operational performance, will be highlighted.

Speaker: Mathieu Sanchez

57 NEW GENERATION IN PRE-HEATING TECHNOLOGY FOR ELECTRIC STEEL MAKING HIGHER PRODUCTIVITY WITH REDUCED POWER

Regulations at the world are accelerating the transition toward a low carbon economy, pushing the industrial sector to reduce the CO2 footprint. Especially EU has set ambitious targets to reduce greenhouse gas emissions by at least 55 % by 2030 and achieve carbon neutrality by 2050. However, despite renewable expansion and the increasing attention on the hydrogen economy, these targets are projected to be missed. New strategies are needed to achieve climate targets, and decarbonization of industrial heat consumption through innovative technologies will play a vital role. Decarbonisation of industrial heat consumption offers an opportunity for energy players and vendors to develop innovative solutions to reduce consumptions.
In this sense, GEMKOM MAKINA has developed a new scrap pre-heating technology in EAF steelmaking where scrap is pre-heated up to 600 °C so that electric consumption is reduced around 100 kWh/ton. This continuous and effective pre-heating technique, called ‘’ Furnace Energy Saving & Continuous Charging (FESCON) System’’, is ‘’environmentally friendly’’ and ‘’high efficiency’’ scrap preheating system to be ‘’superior’’ over the existed systems developed so far. The FESCON System combines the advantages of 100% scrap preheating and continuous scrap feeding through its chambers, without the need of EAF roof opening. FESCON prevents totally, any dust emission and heat loss during furnace charging stage, as it is the case normally for other operations. The FESCON-EAF is a new generation, economical and environmentally friendly Electric Arc Furnace. Considerable reduction in electric energy consumption, increased productivity, meeting strict environmental regulations, less dust load within the melt shop, flicker reduction& harmonic disturbance reduction are some of the key features of the new and superior FESCON system.

Speakers: Mr Bahadir OZAL, Mr dogan ertas

58 Next Generation Power Supply Options for Electric Arc Furnaces and Electric Smelting Furnaces

Utilities globally are shifting towards stricter power quality requirements. This is largely motivated by increasing number of Inverter Based Resources (IBRs) such as, wind turbine and solar panel connected to utility grids and the outlook of the utility generation mix driven by the decarbonization initiatives. Electrical Arc Furnaces (EAFs) for scrap steel making are some of the most electrically volatile utility loads, producing some of the worst power quality conditions. Electric Smelting Furnaces (ESFs) are less electrically volatile than EAFs but can still produce some power quality concerns. The combination of these furnace loads and stricter power quality requirements from the utilities are motivating new technologies to the market, in applications where traditional Static Var Compensation (SVCs) or STATCOMs may not sufficiently compensate furnace loads and meet utility requirements. This paper looks at various prevalent and existing furnace power supplies as well as new and upcoming technologies for furnace power supplies, that specifically aim to connect in series with a furnace load and help clean-up the unstable characteristics of various types of furnace loads. These power supply options have the potential to make it easier for companies to comply with utility requirements when installing new furnaces or retrofitting existing furnaces. This paper also assesses other potential benefits these power supplies can bring to furnace operations.

Speaker: Yan Elksnis (Hatch Ltd)

59 Latest SMS EAF technologies for safety and green steel production

Reduction of CO2 emissions in steel production and conversion to green energy sources demand a highly efficient, dynamic and flexible power supply for electric arc furnaces. Due to changes in the power supply grid by installing more renewable energy resources, grids become weaker and weaker. In addition to that, the grid code, especially regarding flicker values becomes more severe, not allowing the connection of demanding conventional EAFs. The new AURA family of IGBT based power modules provides the demanded efficiency, dynamic and power density to serve the needs of the green steel transformation and grid code requirements. Using this innovative modulation, technologies and proprietary control algorithms, which take full advantage of the power electronic capabilities, SMS ensures highest power transfer and lowest impact on the grid’s power quality.
In addition to X-Pact AURA SMS offers two technological innovations for energy savings, reduced CO2 and NOx emissions, increasing productivity and enhancing safety.
Condoor ®- automatic slag door, with over 50 global installations, showcases design improvements, reliability, and extended lifespan, validated by plant feedback. Its main benefits range from reduced power and electrode consumption to process time. Condoor, combined with SCAD, optimizes parameters like carbon injection and flux consumption, stabilizing cycle times and enhancing slag control, essential for using alternative virgin iron sources in EAF.
X-Pact Sampler, enhances safety by eliminating the need for operators near the furnace. Developed by SMS group, it automates measurements on liquid steel, improving consistency and reducing direct exposure risks. The latest version features heat-armored protections, advanced automation software, and an Automatic Cartridge Exchange system, ensuring reliability and lower maintenance costs. Adaptable to new or existing EAFs, ladle furnaces, vacuum degassers, ladles, or tundishes, it handles all measurement types typically performed by operators.

Speaker: Mr Massimo Lugnani (SMS group)

SMS_Paper_94_2025.07.pdf

Hydrogen-Based Direct Reduction (H-DRI)

5.1.1

Convener: Enrico Malfa (Tenova SpA)

60 Flexible operation of DRI plants integrated with high-temperature electrolysis for cost-effective decarbonization of iron production

Hydrogen-based direct reduced iron (H₂-DRI) represents a promising pathway for significantly reducing CO₂ emissions in iron production. Achieving economic competitiveness for H₂-DRI depends on lowering hydrogen production costs, which can be addressed through: (i) high-efficiency Solid Oxide Electrolyzer Cells (SOECs) and (ii) the flexible operation of both SOEC and DRI plants.
First, this study presents a process analysis of a SOEC-based H₂-DRI plant, evaluating different integration options between the SOEC and the DRI production system: top-gas from the DRI shaft furnace can be cooled down to generate steam for the SOEC feed, or can be directly fed to the SOEC system. All proposed configurations achieve reductions of direct CO₂ emissions of over 90% compared to a conventional natural gas-fed process, with the highest integration achieving a net energy consumption below 8 GJ/tDRI (Scaccabarozzi et al. 2025). The analysis is then extended to assess the off-design operation of the plant, considering both the flexible operation of the DRI reactor and the introduction of natural gas into the reducing loop.
Second, a mixed-integer linear programming model is developed to optimize integration with photovoltaic and wind power generation, as well as storage units. The analysis is conducted for two locations—Cleveland, Ohio (United States) and Pilbara (Australia)—under both short-term and long-term cost scenarios for renewables and storage technologies. Results indicate that a flexible SOEC integrated with an optimized photovoltaic and wind power plant can lower DRI production costs by more than 35%, with respect to an inflexible electrolyzer. Additional flexibility options, such as flexible DRI operation and natural gas injection, contribute to further reducing the required capacity of storage and renewable plants but result in more modest cost reductions (<10%).

Speaker: Marco Ficili (Politecnico di Milano)

61 Real laboratory ‘H2Stahl’ for hydrogen-based direct reduction

In the Real laboratory ‘H2Stahl’ a Direct Reduction test plant will be engineered, build-up and investigated. The actual status of this project shall be presented to the audience.
The German research project is being carried out by the coordinator VDEh-Betriebsforschungsinstitut GmbH (BFI) in Düsseldorf in close co-operation with thyssenkrupp Steel Europe AG in Duisburg. The test plant will be developed and build by TS Elino GmbH, Düren.
The basic engineering for the construction of this direct reduction test plant, including HAZOP, with a throughput of nominal 100 kg/h DRI has been successfully completed and the core components were ordered already for manufacturing. This means that the build-up of the test plant, as well as special investigations which are carried out in the BFI's technical centre, are on schedule. The plant has a height of nearly 24 meter and will use hydrogen from the H2-electroysis plant of the Carbon2Chem-centre in Duisburg. Feed gases such as hydrogen, coke oven gas as well as high and low quality iron ore materials will be tested. The Real laboratory ‘H2Stahl’ is making a decisive contribution to the transformation of the steel industry in Germany.
The basis for supporting industrial, climate-neutral steel production has thus been laid. The direct reduction trial plant will be a part of a test center consisting of hydrogen electrolysis, direct reduction and smelter, which will map future steel production and answer essential technical questions on the safe, economic and trouble-free operation of large-scale industrial plants.
The presentation will give an overview of planning and build-up of the Direct Reduction test plant and shows the innovative plant construction for following direct reduction trials. An outlook on the commissioning as well as on further activities will be given.

Speaker: Dr Ralf Wolters (VDEh-Betriebsforschungsinstitut GmbH)

62 An integrated approach to steelmaking decarbonization: HYDRA project. Description of the innovative open platform and first results

Steel production decarbonization requires innovative technologies to reduce (up to eliminate) fossil materials in the whole chain. This implies alternative iron ore reducing process, new operating practices in the Electric Furnace, new combustion technologies in the downstream processes.
A RINA-CSM project "Hydrogen: innovative plants and related processes for the production of green steel in Europe - HYDRA IT06" was awarded, authorized by the European Commission, and financed by the Ministry of Enterprise and Made in Italy. The activities are distributed throughout six years for about 88M€ budget and aimed at steel production decarbonisation in a DR-EAF route, mostly promising in CO2 abatement potential, using hydrogen also concerning its production, transport and distribution infrastructures issues to boost hydrogen utilization in industry. The project main lines are:
1. study/development of methodologies for testing and qualification of materials/components for H2 local transport, storage and utilization,
2. set up of an innovative hydrogen-powered direct reduction pilot plant (DRP),
3. set up of a pilot electric furnace (EAF) to DRI obtained with Hydrogen, producing "green" steel,
4. hydrogen use in reheating and heat treatment furnaces, improving hydrogen combustion knowledge.

The project also targets coal substitutes use in a logic of circular economy. Advantages of this experimental platform are:
- being a unique opportunity to benefit from synergy among labs and pilot plants,
- being flexible and adaptable to innovative systems, and to fit operating practices to production and quality needs.

Pilot plants and labs will be ready within 2025, with commissioning at early 2026. The operating phase started with modeling of the integrated process, (hydrogen production, iron ore pellets direct reduction, and subsequent melting), as well as parallel lab testing of hydrogen use to reduce iron ore pellets of different quality. The effect of hydrogen combustion on steel surface quality is being assessed as well.

Speaker: Mr filippo cirilli (Rina Consulting Centro Sviluppo Materiali)

63 Results from the HySteel project: integration of solid oxide electrolysis into direct reduction iron systems

With a CO2 emission intensity of 1.9 tCO2/tcrude steel (including both direct and indirect emissions) and a primary energy consumption of 21 GJ/tcrude steel, steel production accounts for the emission of 3.74 GtCO2/y, representing approximately 10% of total manmade emissions. The production of direct reduced iron (DRI), which relies on natural gas to convert iron ore into metallic iron, results in 10.3 tons of direct CO2 emissions per ton DRI, with natural gas contributing approximately 67% of those emissions.
To further lower the direct specific CO2 emissions of this hard-to-abate sector, reducing natural gas can be displaced by introducing electrolytic hydrogen and synthetic gas (syngas) produced at pressure (up to 8 bar) and at high temperature (<800°C) exploiting the waste heat and chemical content from the ironmaking process using solid oxide electrolysis (SOE). The advantageous thermodynamics available in SOE allows converting the available CO2 and H2O from the top gas stream of DRI furnaces into a useful H2-rich stream by supplying renewable electricity at a much lower rate (35 kWh/kgH2) than non-integrated electrolyzer technologies (50-60 kWh/kgH2).
Within the HySteel project, we have demonstrated the integrated detailed design and flexible operation of SOE systems into 2 Mt/y production capacity DRI plants with emission intensities <0.03 tCO2/tcrude steel and primary energy consumption <8 GJ/tcrude steel. We report SOE stacks operating in co-electrolysis up to 8 bar to satisfy the hydrogen and syngas requirements to produce at least 1 ton per week of iron, in addition to co-producing pure oxygen. Techno-economic analyses have shown that costs as low as 270 USD/tDRI, and as high as 393 USD/tDRI are expected with 100% intermittent renewable energy inputs.

Speaker: Luca Mastropasqua (University of Wisconsin-Madison)

64 Calix’s Zero Emissions Steel Technology (ZESTY): Breakthrough pilot testing results for the Hydrogen Direct Reduced Iron (H-DRI) process

Calix’s ZESTY technology is a flash reduction process based on the indirectly heated Calix Flash Calcination (CFC) technology. In 2024, Calix completed a second testing campaign (over 100 runs) with 6 Australian-sourced hematite/goethite iron ores.
The campaign demonstrated it is possible to achieve commercially viable metallisation degrees for a range of ores approaching near-theoretical minimum hydrogen consumption.

This presentation and paper covers the ore testing campaign, the preliminary results on downstream testing of the H-DRIs produced, and the status of TRL development and commercial scale-up, including the design-ready 30,000 tonnes per annum H-DRI demonstration plant.

Speaker: Sebastiaan van Dorp (Calix)

Rolling Mill Technology & Process Optimization

3.1.1

Convener: alessandro ferraiuolo (Marcegaglia Ravenna)

65 Danieli Quali-HSM®: the next gen HSM process

An enhanced strip production concept with Danieli Inductive Heating technology ensuring conventional Hot Strip Mill answers market demand for ultra-thin gauge, high quality and premium grades.
Thick-slab rolling using conventional Hot Strip Mill holds the leading position when it comes to high production capacity, wide and flexible product mix, and premium grades such as automotive exposed and electrical steel.
The modern HSM production faces a triple challenge in the current dynamic market: achieving sustainability, enhancing quality with tight tolerances and uniform properties, and answer market demand for thin-gauge, hot-rolled coil.
The competing in-line casting and rolling technology is a step ahead in many aspects.
The Danieli Quali-HSM® breakthrough process innovation is the answer to those challenges, merging the advantages of both conventional rolling and inline casting and rolling process routes.
The result is the production of HRC at high and uniform temperatures, at a constant speed and down to ultra-thin gauge of 1.0 mm.

Speaker: Mr Antonio Comelli (Danieli & C. Officine Meccaniche S.p.A.)

66 Latest developments in MIDA technology

The latest developments in MIDA (MInimill DAnieli) endless casting and rolling technology represent a significant advancement in the steel manufacturing industry. This innovative process integrates melting, continuous casting and rolling into a single, uninterrupted production line, eliminating the need for intermediate cutting, storage and reheating of the billets, significantly reducing energy consumption and enhancing efficiency and product quality.

The revolutionary DIGIMELTER, the unmatched OCTOCASTER, the elimination of reheating furnaces and the efficient use of raw materials align with the industry’s goals of minimizing environmental impact and promoting sustainable practices. This streamlined approach allows for a more efficient use of resources and a reduction in operational costs, while the integration of automated control systems and real-time monitoring technologies ensures full control over the melting, casting and rolling parameters. This allows for consistent production of steel with uniform properties, enhancing the reliability and performance of the whole transformation process.

The MIDA process is nowadays highly adaptable to different steel grades and product specifications. This flexibility allows manufacturers to quickly respond to market demands and produce a wide range of steel products with varying properties. In conclusion, the latest developments in endless casting and rolling technology offer substantial benefits in terms of efficiency, product quality, sustainability, and adaptability. These advancements position MIDA as a leading technology in the steel manufacturing industry, driving innovation and setting new standards for production processes.

Speaker: Nicolò De Laura (Danieli & C. Officine Meccaniche S.p.A)

67 Multi-functional Simulation System for Continuous Hot Bar Rolling: Development and Industrial Application

Multi-pass hot caliber rolling technology has significant advantages in producing continuous bars, which can be used as structural and connecting parts with essential applications. The efficient production of high-quality bars is of great importance. Simulation is an important tool for reproducing production processes. With the improvement of product quality requirements, people also put forward higher requirements for simulation technology. The simulation model must show the thermal state, microstructure, and hot workability during the bar's high-temperature deformation process. However, such a multifunctional simulation model, especially one that can be applied to a multi-pass hot-forming process, has not yet been reported. Here, a finite element simulation system for hot bar rolling is presented. It is based on the DEFORM-3D software and has been further developed. Based on the embedding of the material model, the simulation model can realize the coupled simulation of temperature, deformation, microstructure, and hot workability. It is worth noting that the model calculation considers the characteristics of multi-pass continuous deformation. We demonstrate the multifunctionality and application of the simulation system based on industrial production processes. The simulation system can be applied to the hot bar rolling process and other multi-pass hot forming technologies. This is important for optimizing the production process and improving product quality.

Speaker: Mr SHUO GUO (Yanshan University)

68 Transforming Steel Manufacturing: Innovations and Achievements in Direct Casting and Rolling

CSP® Nexus is setting the stage for a new generation of direct casting and rolling plants with its latest orders. Unlocked by its high-throughput casting and "real batch" rolling capability, this technology achieves the lowest energy and conversion costs by efficiently utilizing available casting heat through decoupled high-speed rolling in both roughing and finishing stages. Notably, CSP® Nexus will achieve a zero carbon footprint through the complete electrification of its first European reference at Stegra in Sweden.

The order from JSW Dolvi exemplifies CSP® Nexus' ability to integrate the advantages of conventional hot rolling into the direct casting and rolling technology, effectively combining "The Best of Two Worlds". This plant will set several new industry benchmarks: achieving the highest single strand productivity at 4.0 million tons per year (MTPY), producing the widest strips up to 2,600 mm, and manufacturing the thickest strips up to 32.0 mm on a direct casting and rolling plant. These advancements will enable CSP® technology to enter markets traditionally dominated by plate mills, offering significantly better conversion costs.

Moreover, CSP® Nexus' innovative technological solutions are poised to tap into additional markets, such as the production of automotive exposed parts. By leveraging these advancements, CSP® Nexus not only enhances its competitive advantage but also contributes to the broader industry trend towards sustainable and efficient steel production. As the industry increasingly emphasizes environmental responsibility and cost-effectiveness, CSP® Nexus' developments position it as a leader in the transition towards more sustainable practices in steel manufacturing.

This paper will thoroughly examine the various operating modes of batch and endless rolling, emphasizing the current and forthcoming reference plants and will explore the potential to produce grades that are presently supplied solely by the conventional production route.

Speaker: Mr Björn Kintscher (SMS group)

69 The art of keeping up with latest hot strip mill technology – upgrade success stories

Hot strip mills can have a service life of 50 years and more. An ongoing challenge for plant owners is to maintain the competitiveness of their plants over the entire life cycle with constantly new boundary conditions and developments. SMS group offers advanced and innovative technical solutions enhancing the product portfolio, product quality, operational efficiency, sustainability and cost-effectiveness. This paper will discuss such solutions with the examples of coilbox modernizations on the one hand and CVC® plus technology (Continuously Variable Crown) upgrades on the other hand.
Numerous references testify that a coilbox improves thermal homogeneity and reduces heat loss during the coiling process of the transfer bar. By maintaining optimal temperature profiles, the coilbox minimizes energy consumption and reduces the carbon footprint of the mill. This results in significant energy savings and contributes to sustainability objectives by lowering greenhouse gas emissions. At the same time, a coilbox allows the extension of the product portfolio.
CVC® plus technology, on the other hand, focuses on optimizing strip profile and flatness. By enabling precise adjustments of the roll gap, CVC® plus enhances product quality and reduces material waste. This technology not only ensures superior strip quality but also extends the service life of the rolls, leading to reduced maintenance costs and downtime.
Both solutions can be upgraded in existing hot strip mills and come together with advanced automation and digitalization solutions.
In summary, SMS group's modernization competence for hot strip mills offers substantial benefits in terms of sustainability and cost savings. The solutions align with the industry's increasing focus on sustainable practices. Furthermore, the reduction in operational costs and downtime underscores the economic advantages of adopting SMS group's modernization technologies, ensuring that mills remain competitive over their complete lifecycle.

Speaker: Mr Georg Padberg (SMS group)

Surface Technologies

4.3.1

Convener: Giovanni Bolelli (Dipartimento di Ingegneria "Enzo Ferrari", Università di Modena e Reggio Emilia)

70 Modification of Diamond Like Carbon (DLC) to improve specific tribological characteristics for automotive steel components

Carbon-based materials play an important role in today's science and technology. Carbon is a very versatile element whose two most interesting allotropic forms are Diamond (sp3) and Graphite (sp2). On this way the DLC has consolidated all its applications in the automotive and mechanical in general. The management of sp3/sp2 ratio generates various types of DLC that allow to enhance the hardness, contain friction and improve the corrosion resistance of the steel component.
The demand for the application of DLC on steel components for endothermic and hybrid engines (pins, valves, camshafts, gears) is constantly growing; DLC allows improvement in terms of engine performance and reduction of emissions into the atmosphere.
In this presentation, the DLC deposited with hybrid technology PVD-PaCVD (Physical Vapor Deposition- Plasma assisted Chemical Vapor Deposition) will be examined. The modification of the layers, the thicknesses, the compositions, and the containment of surface defects allow enhancing the characteristics of hardness, reduction of friction, and resistance to corrosion of the layer. These characteristics can therefore be objectified with laboratory instruments such as nanoindenter, contact tribometer, and salt spray chamber. The next step is the bench test to appreciate the results near to the real condition. After laboratory analysis and bench tests, the applications are shown in 3 case histories: the increase of abrasion resistance in injection pins, the reduction of the friction coefficient on rocker arms and the corrosion resistance in bipolar plates.

Speaker: Denis Romagnoli (STS srl)

71 Advancements and future prospects of zero emission galvanizing technologies

Sustainability has become a critical concern in the global steel industry. As steel production is inherently resource-intensive and generates significant emissions, the implementation of sustainable practices is crucial to mitigate its ecological footprint. This paper explores the current state and future prospects of sustainable galvanizing technology, a vital process for enhancing steel's durability by applying a protective zinc coating.

Finally, the paper presents case studies of fossil-free galvanizing implementations with zero emission in Europe and abroad, illustrating how these initiatives not only comply with stringent emission permits but also contribute to a competitive advantage in the market.

Speaker: Dr Matthias Kretschmer (SMS group)

72 Investigation on the use of organic acids to pickle the oxide scale of carbon steel hot rolled strips

Carbon steel strips are produced following a series of processes to convert the cast slabs to a coil of flat steel with required dimensions. The hot rolled coil has a protective and adherent layer of oxide scale from 5 to 15 µm thick. Before further processing, this layer of scale is removed in a process known as pickling, which consists of dissolution of the oxides by immersing the steel strip in a bath with strong inorganic acids. The efficiency of the typical inorganic acids: HCl, H2SO4, HNO3 and HF on removing iron and other oxides is unquestionable, however they are hazardous acids with disputed sustainability records.

In this study we investigated the substitution of traditional acids by organic acids. The use of organic acids offers several advantages, including biodegradability, absence of ‘dangerous’ classification, low hazard for humans, the potential for production from carbon dioxide (CO2), and the option to employ regeneration methods other than combustion. Additionally, communities near steel plants have expressed concern about the disagreeable odours associated with the traditional pickling, making the use of organic acids an appealing alternative that could address this issue.

In this investigation, the pickling power of a selected number of organic acids was determined by performing laboratory scale pickling tests on industrially produced hot rolled steel strips. Out of the study, two organic acids give promising results as possible alternative pickling agents: formic acid and methanesulphonic acid. We demonstrated that these two organic acids can lead to a similar pickle-ability to inorganic acids by an appropriate combination of scale breaking, pre-heating of the strip and elevated temperatures on the pickling bath.

Speaker: Mr Sebastien Flament (CRM Group)

73 Innovative “Scale Free” Furnace for section rolling mill

The formation of scale in a reheating furnace is influenced by the O2 content at high temperatures and the residence time within the furnace chamber. Since the temperature and the residence time of the steel are parameters dependent on the process, the only way to reduce scale formation is by decreasing the O2 content in high-temperature zones.
For this reason, Danieli Centro Combustion has studied and already supplied Scale Free Furnaces, capable of operating in a reducing atmosphere under completely safe conditions. This technology, compared to a traditional Walking Beam furnace, not only halves scale formation but also reduces fuel consumption and CO2 emissions.
Scale Free Furnaces are designed to maintain a constant reducing atmosphere, which minimizes the surface oxidation of the steel. This is achieved through precise control of the air-fuel ratio and the use of special burners. Additionally, the reduction in fuel consumption not only lowers operational costs but also contributes to a smaller environmental footprint, making this technology a sustainable choice for the steel industry.
In summary, the adoption of Scale Free Furnaces by Danieli Centro Combustion represents a significant technological advancement, offering benefits in terms of product quality, energy efficiency, and environmental sustainability.

Speaker: Pietro Timossi (Danieli & Officine Meccaniche S.p.A.)

74 Advanced Coating Thickness Measurement in Electrical Steel Manufacturing with EMG SOLID® DFT

Electrical steel is an essential pre-product for efficient electrical devices. In cold rolling processes, an iron-silicon alloy is rolled into thin electrical strips (typical thickness 0.5 mm), which are then annealed and coated with special insulating varnishes. Sheets of different shapes and sizes are then punched and assembled to form magnetic cores. The thickness and homogeneity of the insulating varnish play a special role. Its main functions are insulation, corrosion protection and extension of the life cycle of punching tools.

Traditional measurement methods, such as beta backscattering (BBS), face increasing limitations due to the restricted availability of radioactive isotopes. Infrared (IR) techniques, while viable, struggle with thin layers and surface roughness sensitivity. To address these challenges, EMG has developed the EMG SOLID® DFT system, leveraging laser-induced fluorescence (LIF) to enable high-precision, real-time, inline thickness measurement of insulating layers.

LIF technology offers several advantages, especially high sensitivity, and reduced dependence on surface roughness. The EMG SOLID® DFT system operates by exciting coating molecules with UV laser pulses, detecting fluorescence emission, and correlating it with layer thickness. It is adaptable to various insulation classes (C3–C6) and works at strip temperatures ranging from 50 °C to 150 °C.

Laboratory studies and industrial trials have demonstrated that LIF-based measurements correlate strongly with BBS reference methods, while significantly outperforming BBS and IR sensors in accuracy and resolution. Inline tests in production revealed that even slight variations in coating thickness (as small as 0.1 µm) are clearly detectable, ensuring improved process control and product quality. Additionally, early detection of coating inconsistencies near the drying furnace minimizes material waste and production defects.

With its high-resolution, real-time monitoring capabilities, EMG SOLID® DFT establishes a new industry standard for the measurement of insulating varnish thickness on electrical steel, providing a sustainable and superior alternative to traditional measurement methods.

Speaker: Mark Kreso

Waste Processing & Byproduct Utilization

5.3.2

Convener: Giordano Streghi Montauti

75 EAF waste gas cleaning through iRecovery® system and CataFlex™

Tenova and Topsoe have developed an innovative solution for waste gas cleaning in Electric Arc Furnace (EAF) operations by integrating Topsoe's CataFlex™ technology with Tenova's iRecovery® system. This solution improves waste gas cleaning performance, addressing critical pollutants such as carbon monoxide (CO), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF), and nitrogen oxides (NOx). The iRecovery® system captures the thermal energy from EAF off-gases and converts it into steam for applications like vacuum production and power generation. The system recovers up to 75% of energy, reducing the environmental impact of steel production. The iRecovery® system, through natural circulation ensured by the evaporative system, provides the proper conditions for the catalytic filter bags to function effectively. By incorporating Topsoe's CataFlex™ catalytic inner filter bags in series with iRecovery®, the combined system ensures superior removal of harmful pollutants, achieving higher cleaning performance compared to previous solutions. CataFlex™ technology removes dust and multiple gaseous compounds in a single step. This integration allows for the reduction of CO, PCDD/PCDF emissions to levels below regulatory limits. CataFlex™ can, when used with a reducing agent like NH₃, reduce NOx emissions to operate compliant with regulatory emission limits. The technology converts dioxins and furans into harmless gaseous species and has shown removal efficiencies of >99% at industrial installations. The combination of CataFlex™ with an outer filter bag provides efficient dust removal, comparable to conventional fabric filters, with no significant increase in pressure drop. The lifetime of CataFlex™ matches conventional fabric filter bags, ensuring long-term performance without frequent replacements. One key advantage is the minimization of additional reagents such as activated carbon and calcium hydrate in the waste gas treatment process; this simplifies operation and enhances the potential for reusing the EAF dust. This partnership underscores the commitment of both Tenova and Topsoe to driving innovation and sustainability in industrial processes.

Speaker: Mr Luca Zecchinato (Tenova SpA)

76 Predicting the Reduction Kinetics of the Electric Arc Furnace Dust - A Machine Learning Approach

The recovery of zinc from electric arc furnace dust is primarily carried out in the Waelz process. However, the reaction kinetics within the kiln remain largely unknown as direct measurements or sampling within the kiln are not possible. This lack of insight hinders a comprehensive understanding of the processes and prevents precise optimization of the kiln´s operation conditions.
This work aims to develop a predictive model for the reaction kinetics of electric arc furnace dust in a carbon- and hydrogen-based reduction system. Due to the numerous influencing factors and the complexity of the reactions, thermodynamically modelling the kinetics is mathematically challenging. To overcome this, a machine learning algorithm was employed to model the impact of various input parameters.
The machine learning model was trained using experimental data obtained from thermogravimetric analysis, where specific gas and temperature profiles were applied. These profiles included hydrogen and carbon monoxide as reducing agents. The gas and temperature profiles were systematically varied to aligned to conditions that are typically expected inside the Waelz kiln.
The developed model can be integrated into computational fluid and finite element method simulations to provide, for the first time, a reaction-based representation of the Waelz process using real experimental data. This approach offers a novel pathway for optimizing kiln operation and improving process efficiency.

Speaker: Aaron Keuschnig (Montanuniversität Leoben)

77 Hybrid treatment of Electric Arc Furnace Dust for selective zinc recovery

Electric Arc Furnace Dust is a hazardous waste of steel recycling, containing iron, zinc and heavy metals such as lead, chromium, cobalt and molybdenum. With an average generation of 15-20 kg dust per ton of produced steel, it requires effective processing to mitigate environmental risks and to recover zinc. The best available recycling technology is the Waelz process, that is based on a high-temperature reduction in the presence of carbon as a reducing agent to recover zinc. Despite its industrial relevance, this method has drawbacks, such as high energy consumption and carbon emissions. Over the past few decades, alternative methods such as the Zincex process and various hydrometallurgical techniques have been explored. However, direct hydrometallurgical leaching is hindered by the insolubility of zinc ferrite and the complexity of high-temperature leaching.
This study investigates a hybrid process that combines hydrogen reduction of zinc ferrite to zinc oxide and magnetite, followed by sulfuric acid leaching of zinc. Pyrometallurgical tests conducted at 450 – 550 °C confirm effectiveness of hydrogen in reducing zinc ferrite. However, the process requires control of hydrogen concentration in reducing gas to prior magnetite formation, as soluble iron compounds reduce efficiency of following leaching treatment. Sulfuric acid leaching of a synthetic zinc oxide - magnetite mixture at 30 °C within a pH range of 3.5 – 4.5 identified optimal conditions at pH 4.0 with a duration of 15 – 30 minutes. A 30-minute reduction at 550°C followed by leaching at pH 4 and 4.5 resulted in zinc dissolution of 86% and 71%, with selectivity of 71% and 63% for pure zinc ferrite and EAFD sample, respectively. These results indicate that achieving high zinc extraction with high selectivity remains challenging, requiring further research to minimize iron co-dissolution while maximizing zinc recovery.

Speaker: Aleksandra Kazachenko (Montanuniversität Leoben)

78 Smart robotic system for scrap sorting

The system utilizes one or more robotic arms, depending on plant requirements, to remove impurities from recycled scrap during the final sorting phase. By leveraging an innovative multi-sensor system and a Deep Learning algorithm trained on analyzed materials, the system classifies materials on the conveyor based on their elemental composition (e.g., iron, copper, brass, plastic, etc.).

A 3D scanner guides the robotic arm to precisely identify and extract unwanted elements, discarding them into designated containers. Thanks to its kinematic properties, the delta-type robotic arm achieves up to 45 picks per minute, ensuring high-speed sorting. The system's modular design allows customization to various plant configurations, enabling scalability through multiple robots operating in series and adaptability to different material types via specialized training and custom gripper development.

The circular economy plays a pivotal role in modern industries, particularly in the steel sector, where recycled scrap is a fundamental raw material in electric arc furnace steel production. The quality of the final steel product is directly influenced by the purity and composition of the scrap used, making advanced sorting solutions like this system essential for improving sustainability and production efficiency.

Speaker: ION RUSU (POLYTEC SPA)

79 Technological solutions for pollutants abatement in Steel Meltshop fumes

The latest pollutants emission limits imposed by various governments are forcing some important changes in the world of fumes treatment, also in the iron and steel industry.
New technologies, already applied in other sectors, could now find their way also into this industry to comply with those regulations.
With particular focus to the treatment of the fumes from the Meltshop, Danieli is now able to propose different solutions, specifically customized according to the pollutants to be reduced and the emission targets to be achieved.
The pollutants of major concern in recent times are in particular NOx, SO2 and Particulate Matter (PM): indeed, Danieli has in its portfolio a variety of low impact solutions, that can ensure low to negligible emissions for all of them.
In this paper the different technological solutions proposed by Danieli are presented, together with their application in a case study.

Speaker: Mr Alessio Milocco (Danieli & C. Officine Meccaniche S.p.A.)

Mold Technology & Nozzle Performance

2.3.2

Convener: Riccardo Carli (Prosimet SpA)

80 Concepts for the development of carbon free mold powders for the continuous casting of steels

In the continuous casting, mold powder is added to the molten steel meniscus, where it forms a liquid slag that also contains a carbon-enriched layer. This phenomenon occurs even in ultra-low carbon steels, where small amounts of carbon are used to control the melting behavior of the mold powder. During the process, the liquid steel may come in contact with this layer leading to steel re-carburization and a subsequent reduction in quality. Therefore, the development of carbon-free mold powders is essential.
First, possible melt controlling additives were selected, and mixtures composed of standard raw materials were defined ensuring the same slag composition as the conventional mold powder after liquefaction. Mold powders and the prepared mixtures were filled into steel crucibles closed by a lid, and inserted in a laboratory furnace preheated to temperatures between 900-1200°C to simulate high heating rates. After a dwell time of 10 minutes, the samples were quenched to room temperature and mineralogically investigated. SiC, without the addition of any antioxidants, proved to be a suitable replacement of carbon. Attempts to reduce its content led to a significant decrease of CO2-emission from the mold powder. To further minimize the carbon content in mold powders, a new approach was developed. The raw materials required for each mold powder were assigned to a basic or an acidic group. Granules were produced from each group, subsequently mixed and subjected to thermal treatment. Mineralogical analyses revealed that the separation of basic and acidic raw material components delayed the formation of new phases such as cuspidine or equilibrium liquid phase. This may be attributed to suppression of intermediate liquid phases in disequilibrium and increase of diffusion path. Following, the amount of melt-controlling additives was further reduced or even eliminated in selected samples, what did not negatively affect their melting behavior.

Speaker: Nathalie Gruber (Montanuniversitaet Leoben - Chair of Ceramics)

81 Continuous Casting Mold Flow with Original and Used Nozzle Geometries: Numerical Flow Simulations and Water Model Measurements

In continuous steel casting, the turbulent liquid steel flow in the mold has a significant influence on the produced steel quality. The varying process parameters casting speed and inert gas injection at the stopper rod tip influence the mold flow pattern. Most investigations consider the original geometry of the submerged entry nozzle. During the casting process, material deposition and erosion change the nozzle surface geometry continuously. The geometries of two used nozzles are determined by a 3D scan at voestalpine. Numerical multiphase flow simulations and 1:1 scaled water model experiments are performed for the used and unused nozzle geometries and compared. The used nozzle geometries show significantly different flow patterns in comparison to the original unused nozzle geometry.

Speaker: Mirko Javurek (Johannes Kepler Universität Linz, Institut für Strömungslehre und Wärmeüübertragung)

16:10 Coffee break

Blast Furnace Process Optimization & Control

1.3.1

82 Deep Learning Model to Predict the Remaining Time to Close Tap-holes for Blast Furnaces

Manufacturing steel requires extremely challenging industrial processes. In particular, predicting the exact time instance of opening and closing tap-holes in a blast furnace has a great influence on steel production efficiency and operating cost, in addition to human safety. However, currently predicting the time to open and close tap-holes of the blast furnace still highly relies on manual human expertise and labor. Also, most of the prior research is limited to indirectly model the level of liquids in the hearth, using complex mathematical models or classical machine learning approaches. In this paper, we use a data-driven deep learning method to more accurately predict the remaining time to close each tap-hole in a blast furnace and develop an AI-enabled automated prediction system to reduce manual human error as well as reduced the waiting TLC (Torpedo Ladle Car) time before pouring pig-iron in blast furnace.
We develop a multivariate time series forecasting algorithm using Convolutional Neural Networks (CNNs) and Long Short-Term Memory (LSTM) models to predict the opening and closing time more accurately for the blast furnace of POSCO. In particular we use and validate data from one of the largest operating furnaces in the world to develop our system. Our proposed Skip-dense CNN (S-CNN) model achieved more than 85% accuracy within ±15 minutes tolerance, compared to the operator's time to close tap-holes for blast furnaces. Our S-CNN model has been successfully deployed at a large-scale blast furnace of POSCO since January 2018 and has achieved similar accuracy. And we even reduced the TLC cycle-time in a real operational environment by reduced the waiting TLC time before pouring pig-iron in blast Furnace.

Speaker: Dr Seungmoon Lee (POSCO Technical Research Laboratories)

83 Implementation of EASyMelt with Ammonia and HBI Charging to Achieve Ultra Low Carbon Ironmaking

Despite being the largest emitter of CO2 in the steel industry, the blast furnace (BF) process remains dominant due to its high productivity, cost-effectiveness and flexibility in ore usage. Still, with the proliferation of policies geared towards curbing CO2 emissions, the BF process must transition towards operation with lower emissions. In that context, Paul Wurth S.A. has unveiled EASyMelt, a technology to reduce CO2 of the blast furnace in a stepwise approach. If EASyMelt has a high flexibility in energy inputs, ammonia and Hot Briquetted Iron (HBI) are of particular interest due to their potential to relocate energy consuming steps. Indeed, they are both storable, transportable and can be produced in regions with good availability of renewable energy. In this study, the implementation of the EASyMelt concept with ammonia and Hot Briquetted Iron is evaluated using a newly developed numerical simulation model. In addition to the potential coke and CO2 savings, the impact on the furnace’s internal state is investigated. A particular focus is given to the furnace permeability, the thermal and chemical behaviors, as well as the cohesive zone characteristics.

Speaker: Mr Florent Mauret (SMS group)

84 Reducing blast furnace CO2 emissions

Blast furnaces are a key lever for reducing the CO2 emissions of the steel industry. This paper will review the available technologies and best practice for blast furnaces and the effect they can have on reducing CO2 emissions. The OPEX and CAPEX costs and benefits will be discussed, with a view to identifying the “low hanging fruit” for steelmakers to implement. These options will include specific technology solutions, such as Sequence Impulse Process (SIP) and the use of Digitalization Technologies and advanced process control.
The paper will also assess the feasible medium- and longer-term developments (for example top gas recycling and carbon capture), considering the risks to actual commercialisation along with the potential for decarbonisation and competitiveness.
The findings will underscore the importance of adopting a multi-faceted approach when considering how to mitigate environmental impact while maintaining operational efficiency.

Speaker: Dr Edward Long

85 AI-Powered Cohesive Zone Optimization: Enhancing Efficiency and Stability in Blast Furnaces

The position of the cohesive zone (CZ) in a blast furnace significantly impacts process efficiency and stability. A lower cohesive zone increases dry burden volume, promoting indirect reduction of iron ore and improving energy efficiency. However, excessive downward movement reduces the distance to the dead man, leading to operational instability, irregular gas flow distribution, unsteady coke supply to the raceway, successive burden slips, and potential productivity losses. Maintaining the cohesive zone within an optimal range is crucial for balancing energy efficiency with stable furnace operation.
To address this challenge, we developed an AI-driven tool designed to estimate the position of the cohesive zone root and provide dynamic control recommendations. By analyzing key operational parameters such as hot blast data, gas utilization, burden distribution, and pressure drop, the system aims to predict cohesive zone behaviour and suggest adjustments to maintain optimal conditions. The tool leverages machine learning models trained on historical furnace data to enhance decision-making and improve process reliability.
This AI-based approach enables proactive control strategies, reducing reliance on empirical adjustments and enhancing process stability. By integrating machine learning with process knowledge, our solution helps operators maximize indirect reduction, optimize fuel consumption, and mitigate risks associated with excessive cohesive zone movement. If successfully deployed, this technology could significantly enhance blast furnace control, offering a data-driven framework to improve energy efficiency, operational stability, and overall ironmaking performance.

Speaker: Dr Johann Wachlmayr (Austria)

86 Breaking boundaries: Tata Steel's H Blast Furnace sets new standards

This paper examines the unprecedented achievements of Tata Steel's H-Blast Furnace at Jamshedpur, which has surpassed 50 million tons of hot metal production in the present campaign (as of January 8, 2025), without requiring major mid-campaign repairs. Commissioned in 2008, the furnace has consistently exceeded its designed by more than 20% annually, establishing new benchmarks in operational efficiency and sustainability within the Indian steel industry. This Blast furnace has consistently set records for PCI injection and fuel efficiency, even when working with high slag rates.
The project commenced in August 2005, with the construction awarded to a consortium led by SMS group and Larsen & Toubro. Featuring a substantial inner volume of 3814 m³ and an annual production capacity of 2.5 million tons, the furnace was the largest in India at its inception. Completed in a record 25 months from groundbreaking.
This paper highlights the integration of advanced technological solutions, which contribute to enhanced energy efficiency and environmental sustainability, as well as aiming to provide a comprehensive analysis of the technological advancements strategies that have contributed to this landmark achievement.

Speaker: Mr Cristiano Castagnola (SMS group)

87 Monitoring of blast furnace wall pressure profiles and their relation to process efficiency

The blast furnace process for Ironmaking is highly optimised and very energy efficient. At the same time due to its dependency on coke, not only as an energy carrier but also as a chemical reductant and provider of gas permeability, it is responsible for high CO2 emissions. Consequently, steel producers search for operation modes, e.g. such as increased share of hydrogen based reduction, to minimise emissions. For such new operational set points, operators have less experience in how to maintain a stable and most efficient process state.
Experience at HKM is, that especially in the shaft region of the blast furnace most process instabilities arise from non-optional gas permeability of the burden column and non-uniform burden descend. Such process disturbances can be recognised already in a very early beginning state by careful monitoring of the gas pressures along the shaft wall.
This article explains how to automatically filter measurement readings from such sensors. Then a systematic data analysis is carried out to highlight relations between vertical pressure profiles and performance indicators such as gas utilisation. Finally, an online operation support system is introduced which automatically monitors and analyses the permeability profiles to identify arising issues. Such a system enables operators to rate the current operational risk for permeability disturbances, to prevent control actions which might further decrease the permeability and to decide about appropriate counter measures.

Speaker: Hauke Bartusch (VDEh-Betriebsforschungsinstitut GmbH)

88 Campaign Life Extension of Hot Stoves in Blast Furnace Ironmaking

The effective operation of hot stoves is critical to profitable blast furnace ironmaking. High hot blast temperatures and stable stove operation enable consistent metal production at low cost. Conversely, damage and operational disruptions affect process efficiency, iron quality, and downstream activities. While it is important to address damage expeditiously, comprehensive repairs are laborious, expensive, and require complex safety planning when executed independent of a planned shutdown. The campaign life assessment methodology incorporates a multi-disciplinary approach to study all elements of the hot stove while identifying options to safely extend its life. Operations, maintenance, and engineering teams work closely to develop practical strategies to maintain reliability and improve safety, while meeting business objectives through targeted repairs and interventions. This approach requires careful planning and execution to evaluate the remaining campaign life and achieve extension targets.

Speaker: Steven Samuel (Hatch)

Green Steel Technologies

5.3.3

Convener: Jens Kempken (SMS group)

89 Globalization cancelled?

The steel trade has long been a cornerstone of interconnected global production networks. Yet, as the industry faces unprecedented challenges—ranging from chronic overcapacity to divergent decarbonization trajectories—the protection of domestic markets is emerging as a critical priority. Around the globe, measures such as anti-dumping regulations, tariffs, safeguards, and subsidies are reshaping the competitive landscape.

Add to this a potent mix of geopolitical tensions, supply chain vulnerabilities, and the transformative impact of trends like automotive electrification and state-driven subsidy programs, and we see the contours of a seismic shift: a pivot toward regionalization and even re-industrialization.

Is this the dawn of a new era—a rewinding of globalization as we know it? If so, how will these tectonic changes redefine the business models of steel producers and buyers alike? Join us as we explore the implications of this turning point and what it means for the future of the steel industry.

Speaker: Ms Nicole Voigt

90 Thick Slab Casting Technology for renewable energy produced by windmills

Wind power plays a central role in the global energy transition and is one of the most sustainable methods of electricity generation. It harnesses the kinetic energy of the wind and converts it into electrical power through wind turbines, without emitting greenhouse gases. Windmills are a crucial component of the shift to renewable energies as they provide a reliable, cost-effective, and environmentally friendly energy source.

One of the key components of this technology is steel, which is indispensable in the towers, rotor blades, and foundations of windmills. High-strength steel ensures the stability and longevity of the installations, which often have to withstand extreme weather conditions. Thus, steel is an essential material that significantly contributes to the economic feasibility of windmills.

The required performance of the steel components is achieved through a combination of steel alloy, casting formats, and casting technology. Regardless of whether the mills are operated in onshore or offshore wind farms, steel plates with thicknesses greater than 100 mm are required.

The presentation discusses the significance of continuous casting plants with specific casting thicknesses for the construction and operation of leading-edge windmills.

Speaker: Dr Jochen Wans (SMS group)

91 Sustainable biogenic carbon for metallurgical use

In order to remove fossil carbon from the metal industries, biogenic carbon sources are needed. Progress has been made in using biogenic carbon substitutes in pilot and industrial-scale trials. However, challenges remain in the production and use of metallurgical biocarbon products, particularly in areas such as policy support at national and EU levels, commercial financial incentives, competing demand on biomass feedstock, and raw material costs.

The HåBiMet project, funded by Swedish government agencies, aims to investigate the barriers and opportunities for promoting the production and consumption of metallurgic biocarbon products in a Swedish context. The project adopts three perspectives: technical, social, and policy-related. Key focus areas include identifying conflicts of interest regarding more sustainable use of biogenic carbon at the societal level and optimizing the biochar value chain for sustainable metallurgical industry, etc.

Potential enablers include synergies in the production of biocarbon products involving the metallurgy, district heating, and chemical sectors. Since bioenergy is the largest energy source in Sweden, a shift in the use of biomass could have significant impact on the energy market and forestry sustainability goals. The HåBiMet project addresses the challenges by fostering broad collaborations that bring together the most relevant sectors, including agriculture, energy, and metal production. It is clear that achieving wide adoption of biogenic metallurgical carbon requires sector-wide acceptance and coordination.

The HåBiMet project has gained valuable experience in building these broad and cross-sectoral collaborations and will present an outlook on the next steps toward creating a sustainable market.

Speaker: Mr Erland Nylund (Swerim AB)

92 Transitioning to Green Steelmaking: Environmental Considerations of Electric Arc Furnaces

The transition towards green steelmaking necessitates fundamental modifications to existing production routes, particularly through the integration of electric arc furnaces (EAF) within integrated steel plants. This shift offers operators new opportunities, including the production of new steel grades and flexible raw material inputs. However, the environmental implications of EAF installations must be carefully assessed to ensure sustainable project development. A primary concern is the significant noise emissions associated with EAFs, which are notably higher than those from oxygen steelmaking plants. Consequently, substantial efforts in noise mitigation, such as insulation and enclosures, are essential.
Additionally, minimizing pollutants, including particulate matter and organic components, is crucial. The implementation of advanced gas cleaning systems, often incorporating a waste heat recovery plant. This recovered heat is typically utilized to generate steam for existing plant operations, enhancing overall energy efficiency. Modern EAF facilities also prioritize the safety and protection of personnel, addressing sound mitigation and dust exposure through the use of protective structures like doghouses.
Furthermore, the integration of modern off-gas treatment systems necessitates a high degree of automation. Digitalization packages, featuring acoustic and optical sensors alongside intelligent control systems, are increasingly employed to optimize these processes.
This comprehensive approach ensures that the transition to green steelmaking not only meets environmental standards but also enhances operational efficiency and worker safety.

Speaker: Thomas Steinparzer (Primetals Technologies Austria)

93 Production of hydrogen-rich synthesis gas for blast furnace injection by exploiting coke breeze combustion to reform coke oven gas.

The iron and steel sector leads in CO2 emissions and ranks second in energy consumption among heavy industries. It directly contributes 2.6 gigatonnes of carbon dioxide (Gt CO2) annually, accounting for 7% of the global energy system's total emissions. Currently, it is the largest industrial coal consumer, meeting approximately 75% of its energy demand. Despite global reliance on blast furnaces (BF) for iron ore reduction, the main contributor to CO2 emissions in integrated BF-BOF steelmaking is primarily driven by the need for carbon, typically supplied by coke, as the reducing agent.
In this frame the main objective of the ProSynteg project is to reduce the coke rate and associated CO2 emissions from Blast Furnace (BF) by means of the realization of new module of oxy-combustion of coke breeze that will be installed in an industrial coke plant to test, in a real operating industrial environment, the production process of hot syngas using the CO2 coming from the oxy-combustion of coke breeze for dry reforming of Coke Oven Gas (COG). This process has been designed to be flexible in terms of input streams and to produce a hot syngas, rich in H2, ideal for direct injection in the BF, resulting in the reduction of its coke rate and associated CO2 emissions.
The pilot tests will be complemented with supporting lab works. Moreover, a dedicated process model will also be developed and tuned to extrapolate the pilot results at the full industrial scale of a modern BF. Finally, a full evaluation of the industrial potential of the process will be carried out, with detailed calculations of the CO2 mitigation effect and process economics.

Speaker: Mr MATTEO GILI (RINA-CSM)

94 Yield increase by hot strand coating in continuous casting of long product

The transition to green energy and the reduction of carbon footprints in the steel industry are essential for sustainable steel manufacturing. Optimizing casting processes in steel plants can lead to substantial reductions in emissions and operational costs, aligning with the increasing demand for eco-friendly products.
In the context of the continuous casting process for billets, scale formation presents challenges such as material loss, surface damage, equipment degradation, contamination of process paths, and significant cleaning efforts. Standard solutions to mitigate these issues include high-pressure water descaling, chemical deoxidation, and the application of coatings. However, complete prevention of scale formation is not possible. These strategies are typically applied in downstream processes; however, they have not yet been extensively implemented in the Continuous Casting Machine (CCM).
This paper emphasizes strategies developed to reduce scale formation during the continuous casting process, particularly by usage of spray coating powder. The powder is applied in precisely controlled doses to the hot billet surface via dedicated spray equipment at the end of the secondary cooling zone. By contact with the hot billet the powder rapidly melts, adheres to the billet surface and forms an inertial layer preventing from steel oxidation and consequentially reducing new scale formation.
For various applications and steel grades powders have been specifically developed. The tests have successfully been conducted at different steel plant installations, demonstrating their remarkable efficiency in reducing the oxidation rates and scale formation. The integration of this newly developed technology contributes significantly to cost savings, as it increases yield, improves product quality and reduces necessary downtimes for maintenance and cleaning. Consequently, the overall plant operational efficiency and competitiveness in the metals industry market can be enhanced by this new application in the continuous casting process.

Speaker: Gian Hauenstein (SMS group)

95 Application of a novel biowaste-derived biocoal as coal substitute in Electric Arc Furnace

The utilization of biochar as valid alternative to fossil coal for steel bath carburization and slag foaming has already been proved with small scale and industrial tests.
The material availability and the related cost remain important issues to allow the utilization of biochar in current industrial practice. Reusing biogenic wastes is a promising solution, but the concentration of inorganics (P, K, Na, etc) can be harmful for the use in the steelmaking sector. In this project, four different biocoals have been produced starting from straw, sludge from water treatment plant, digestate from animal dejection, and organic fraction from municipal waste. The biogenic materials have been pyrolyzed and then processed by chemical leaching following a RE-CORD patented process. Leaching contributes to increase the quality of the biocoal, as it reduces the ash content of the char, increasing the C content of > 30%, the calorific value of up to 50%, and make the biocoal less reactive at high temperatures. In parallel the leachate is rich in elements (as phosphorus, potassium, calcium) which can be further recovered and valorized in agriculture. The thermal behavior of the material has been characterized by thermogravimetric analysis. The pellets obtained from pyrolyzed and leached materials have been used in melting tests in a laboratory furnace, to study the interaction of biochar in contact with molten bath.
The characterization activities and the performed tests gave positive results respect potential industrial utilization of these materials.
These activities have been carried out in the frame of Research Fund for Coal and Steel within the project BIObased REsidues Conversion to Advanced fuels for sustainable STeel production – BIORECAST.

Speaker: Mrs Valentina Alemanno (Rina Consulting Centro Sviluppo Materiali)

Hydrogen-Based Steelmaking Technologies

5.2.1

Convener: Enrico Malfa (Tenova SpA)

96 Hydrogen Reduction of Manganese and Iron Oxides in a Commercial Manganese Ore: Thermochemistry and Kinetics

Abstract:

The transition from solid carbon to hydrogen gas in ferromanganese production represents a transformative strategy for reducing carbon emissions in the ferroalloy industry. The HAlMan process, an innovative hydrogen-based reduction method, has advanced from laboratory-scale research to pilot-scale validation, demonstrating significant potential for decarbonizing ferromanganese production. This breakthrough technology could reduce CO2 emissions by approximately 1.5 tonnes per tonne of ferromanganese produced, marking a critical step toward sustainable metallurgy.
This study examines the thermochemical behavior and the reaction kinetics of a commercial manganese ore during hydrogen pre-reduction in a laboratory-scale vertical thermogravimetric furnace under isothermal conditions. Experiments were conducted at temperatures ranging from 600°C to 900°C to assess the reduction behavior and determine the rate-limiting mechanisms. Thermogravimetric analysis (TGA) was employed to monitor weight loss, enabling precise reduction rate measurements. Reduction progression was evaluated using XRF, XRD, BET, and SEM analyses to investigate compositional, mineralogical, and microstructural transformations.
The results indicate that the simultaneous hydrogen reduction kinetics of manganese and iron oxides in the ore are strongly temperature-dependent, with higher temperatures facilitating faster reduction and phase transformations. Complete reduction to metallic Fe and MnO was achieved at 800°C and 900°C within two hours, whereas lower temperatures required extended holding times to reach similar extents of reduction. Additionally, sintering effects were observed above 700°C, as evidenced by a decrease in BET surface area and pore volume.
These findings provide valuable insights into the hydrogen reduction mechanisms of manganese ore, supporting the development of an environmentally sustainable pathway for ferromanganese production.

Keywords: Hydrogen reduction, Thermogravimetry, Isothermal reduction, Thermochemistry, Kinetics, Manganese ore, Porosity, Surface area.

Speaker: Alok Sarkar (Norwegian University of Science and Technology (NTNU), Norway)

97 Ammonia as a Cost-Effective Energy Carrier for Decarbonization in the European Steelmaking Industry

This paper analyses the potential of ammonia in the decarbonization race within the steel industry and gives an outlook in presenting realistic, cost competitive decarbonization solutions such as the Paul Wurth EASyMelt.
Ammonia, with its high hydrogen content and established infrastructure, presents a viable alternative to pure hydrogen. The European Union's commitment to carbon neutrality by 2050 has driven the exploration of low-carbon technologies. Traditional steelmaking processes, which rely heavily on coking coal, produce approximately 1.8 tonnes of CO2 per tonne of steel. Transitioning to hydrogen-based Direct Reduction of Iron (H-DRI) can reduce these emissions significantly. However, the high costs associated with hydrogen production and storage pose economic challenges.

Ammonia offers a cost-effective solution due to its lower production and storage costs compared to hydrogen. The production of ammonia via renewable energy sources, such as wind or solar power, can achieve near-zero carbon emissions. In Europe, the cost of renewable electricity can be €100/MWh or more due to the high demand. Fortunately, ammonia enables large energy consumers to use imported and stored energy efficiently from regions with significantly lower renewable electricity prices below 30€/MWh. Ammonia can therefore significantly lower OPEX for large industrial hydrogen consumers, whilst leveraging existing infrastructure to minimize CAPEX.

Additionally, ammonia's efficient integration in CO2 lean steelmaking process can further enhance its economic viability. For instance, the cost of producing hydrogen through electrolysis is estimated at €4-8/kgH2, whereas ammonia production costs are lower, at approximately €2-4/kgH2. These cost advantages are further amplified by efficient usage in the Paul Wurth EASyMelt process, positioning ammonia as a key enabler for the decarbonization of the steelmaking industry in Europe.

Speaker: Mr Jihong Ji (SMS group)

98 Electrification of heating in steelmaking – an enabler of fossil-free steel

Current heating technology is predominantly gas-fired and there is a strong drive and commitment, from the steel industry to reduce emissions in steelmaking. Resistance heating technology potentially offers unique opportunities to reduce or remove use of fossil fuels while at the same time increasing thermal efficiencies, improving the work environment and enabling delivery of a fossil-free product.
This presentation addresses heating challenges along the entire chain of iron- and steelmaking, from the DRI and Blast furnace to downstream heat treatment processes.
The focus of this presentation is to highlight the latest developments in electric heating technology along the entire iron- and steelmaking process chain.
Examples of different electric heating solutions and select case stories for the different processing steps within steel production will be discussed. Results from the latest developments in electric gas heating will be discussed. Recent advancements within electrification of ladle heating and the ongoing development of electric heating solutions for reheating furnaces will be presented. To summarize, there is great potential to electrify heating processes within iron- and steelmaking, the main challenges are to develop large-scale and robust solutions to satisfy the current and future needs of the steel industry.

Speaker: Dr Dilip Chandrasekaran (Kanthal)

99 Hydrogen plasma smelting reduction of Cr2O3/Chromite: the first step to direct and sustainable production of stainless steel

By the end of 2050, the European Union aimed to decrease the carbon-based greenhouse gases (CO and CO2) considerably. It was targeted to achieve 80-95% less than the level of emissions in 1990. Hydrogen, as a clean reducing agent, can eliminate the carbon footprint from the steel industry considerably (up to 95%). However, some factors, such as the endothermic nature of H2 reduction, and the thermodynamic resistance of some high-temperature mineral oxides against reduction by H2 hinder such achievement. Hydrogen plasma smelting reduction (HPSR), as an alternative promising method compared to direct H2 and conventional carbon-based reduction methods, has emerged both in the lab and on a pilot-scale plant in the current years. The direct reduction of chromite ore by HPSR, containing both Cr2O3 and Fe2O3 (and FeO), enables single-step production of low-carbon ferrochromium and stainless steel. Chromium is the major alloyed element of stainless steel produced mainly through the primary metallurgy methods from chromite ore. The ore contains different mineral oxides in the spinel phases that complicate the reduction process. Therefore, the study of different factors on the reduction of pure Cr2O3 by the HPSR method is the first step in evaluating the feasibility of ferrochromium production by HPSR. This state of matter provides enough reactivity and heat via the excited species of hydrogen to overcome the mentioned kinetic (THP = 5000-25000 K) and thermodynamic (ΔG°HP ≤ -1500) obstacles. In this paper, the in-situ evaluation of effective parameters, such as hydrogen utilization, reduction degree, etc., by optimizing gas flow rate melting temperature, and activity on pure Cr2O3 and the mixture of it with selective acidic and basic fluxes were studied. Moreover, the required thermodynamic assessments for the experiment were conducted to clarify the feasibility of the reduction process.

Speaker: Mohammad Jafarzadeh (K1-MET)

100 Development and Testing of a Hydrogen-Fueled Burner-Injector System for EAF Applications: A Clusters4Future Initiative

In the public funded project “HyInnoBurn – Industrial Gas Burners” a 450 kW prototype of a hydrogen fueled burner-injector system for use in EAF has been developed and additive manufactured in pure copper. This project is part of the German Clusters4Future initiative, supported by the German Federal Ministry of Education and Research (BMBF).
Uncertainty in the future gas supply (natural gas, bio methane, green hydrogen) is prevented by the fact that the burner-injector can be operated with hydrogen or natural gas and at arbitrary mixing ratios. Burner-injectors of different sizes were tested with different fuel gases as free flame test as well as in a large-scale laboratory furnace. In parallel, the combustion process was simulated based on the URANS equations and the GriMech 3.0 combustion model. High resolution simulations for different mixing ratio between hydrogen and natural gas show the influence on the flame structure, the flame temperature and the species distribution. The results indicate that the operation of an EAF without fossil fuel and without additional CO2 from burners is generally possible. In Phase 2 of this project (02/2025 – 01/2028) the 450 kW prototype burner-injector will be scaled up to full size (4 MW) to be used in an industrial 125 t DC EAF. Additional to the design and development of the additive manufactured burner the development of the necessary infrastructure for hydrogen use in an existing plant is a significant challenge.

Speaker: Dr Fabian Krause (SMS group)

101 Replacing natural gas with Hydrogen in heat treatment furnaces: impact on scale formation, surface quality and pickling kinetics of stainless steel

This study investigates the effects of replacing natural gas with Hydrogen in heat treatment furnaces for stainless steel strip (both austenitic and ferritic grades). Using Hydrogen as a fuel, the vapor content in the furnace atmosphere increases, which could affect the characteristics of the oxide scale, including its composition, thickness and adherence to the base metal. Eventually changes in scale characteristics may subsequently impact on scale removal processes, such as descaling (mechanical or electrolytic) and pickling, thereby influencing the kinetic and quality of the steel surface.
The experimental scenario was defined to verify the effects of the combustion atmosphere simulating the annealing process and the subsequent scale removal process of three types of stainless-steel products AISI 304, AISI 316L and Type 441, either cold or hot rolled.
The stainless-steel samples underwent oxidation and annealing tests in both 100% natural gas and 100% Hydrogen combustion atmospheres at three different thermal cycles, specific for each steel grade. After the thermal treatment the oxidation state of the scale formed in both combustion atmospheres was analyzed using advanced techniques such as scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS) and Glow Discharge Optical Emission Spectroscopy (GDOES) to characterize the morphology and chemical composition of the formed oxides. A comparative analysis was performed to find the differences among the scale characteristics formed in the two combustion atmospheres.
Once the scale was characterized, the effect of the combustion atmosphere on scale removal was studied. An experimental comparison was made by determining the minimum pickling time (through visual inspection and weight loss comparison) and the impact on productivity. For a more in-depth evaluation, the surfaces of the samples were analyzed using SEM and optical microscopy.
This research underscores the potential of Hydrogen combustion as a sustainable alternative to natural gas, with no carbon emissions in annealing furnaces.

Speaker: Niccolo Massarelli

102 Advancing hydrogen plasma smelting reduction: Experimental insights from a pilot plant

The hydrogen plasma smelting reduction process is a promising technology for sustainable steel production from iron ores, utilizing molecular, atomic and ionized hydrogen as reducing agents. The reactor is a gas-tight direct-current electric arc furnace with a hollow graphite cathode for material and gas feeding. To investigate scale-up parameters, a pilot plant with a capacity of 100 kg iron ore per trial has been built at the site of voestalpine Stahl Donawitz GmbH in Leoben, Austria, and is operated by K1-MET GmbH, Linz, Austria. This study examines the impact of selected parameters on the reduction process. Therefore, thermal insulation is applied to the vessel above the crucible to mitigate heat losses and enable higher bath temperatures. Furthermore, different crucible refractory materials are evaluated for their performance, especially their chemical interference with the slag. Additionally, pre-reduced material is processed and the differences in reduction kinetics are discussed. These combined results provide insights into the optimization of process conditions for hydrogen plasma smelting reduction at pilot scale.

Speaker: Bernhard Adami (K1-MET GmbH)

Mold Technology & Nozzle Performance

2.3.2

103 The interplay of SEN design and flow dynamics in thin and mid slab casting

Thin slab casting is a well established technology in modern steel making, offering significant advantages in terms of efficiency, cost-effectiveness, and environmental sustainability compared to standard slab casting. As the industry trends towards even higher productivity, a new type of casting machine operating at medium thick moulds seem to be the emerging trend. One key factor contributing to a stable process and quality of the cast product in both types of units is related to the fluid flow pattern in the mould. In this context, the design of the Submerged Entry Nozzle (SEN) warrants special attention. The study employs both numerical simulation methods (CFD) as well as water modelling techniques to analyse the interdependency of molten steel flow patterns, nozzle geometry, and casting parameters, such as casting speed or slab dimensions, based on several examples.

Speaker: Gernot Hackl (RHI Magnesita GmbH)

104 Characteristics of Nozzle Clogging and Evolution of Oxide Inclusion for Al-Killed Super304H Stainless Steel

This study addresses the issue of nozzle clogging failure in the continuous casting of Super304H stainless steel, investigating the impact of inclusions on nozzle clogging formation through experimental and thermodynamic calculations. Initially, the clogged nozzles were systematically examined, followed by the study of the evolution of steel melt inclusions at different stages of the smelting process. The study revealed that nozzle clogging consists of three layers: Layer A, the initial cold steel layer, primarily composed of eroded refractory material and cold steel; Layer B, the slag-type inclusion layer, predominantly consisting of Al-Ca-Si-Mg-F-O inclusions, with a high content of Al2O3; and Layer C, the clogging layer, mainly composed of some slag-type inclusions, a large amount of endogenous Al-Ca-Si-Mg-O inclusions, and cold steel. The study demonstrated that slag-type inclusions in the steel melt gradually increase in Al2O3 content and decrease in liquid phase ratio under cooling and oxidation, leading to the formation of the slag-type inclusion layer B. To reduce the formation of Layer B, the Al2O3 content in inclusions during the tundish stage should be controlled to below 56%. Additionally, during the tundish stage, endogenous inclusions with a high Al2O3 content, in addition to slag-type inclusions, generate a porous network in Layer C, which ultimately impedes the flow of steel and leads to nozzle clogging formation. To ensure smooth continuous casting, it is recommended to control the T.O content within the range of 0.0049% to 0.0075% and ensure that the liquid phase ratio of endogenous inclusions exceeds 50%. This study provides theoretical basis and technical support for optimizing the steel melting process, reducing nozzle clogging defects, and improving steel quality.

Speaker: Tong Qiao (State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing)

105 Arcelormittal Industeel slab caster conversion to ODS fibers with the Fiberstrand® technology.

Arcelormittal Industeel Belgium is steel plant producing carbon, low alloy, stainless steels and nickel based alloys through a single strand continuous caster, in combination with a plate mill.
Following a trial with FBG fibers horizontally installed in the broad face plates that took place in 2024, Industeel has decided to convert their slab caster to the latest technology of EBDS Engineering: the ODS fibers with the Fiberstrand ® solution to install them, behind electron beam welded inserts in the broad face copper plates.
The Optical Distributed Sensing (ODS) is a technique that can read, with a very high resolution, the temperature of an optical fiber, with more than 1000 measuring values per horizontal line in the copper plate. The Fiberstrand® technique is unique solution, that allows to store permanently the fibers at the caster. Only the mold that is installed on the strand is receiving the fibers, traveling through special guiding hoses up to the copper plate.
The chosen solution will comprise 3 horizontal fiber lines per broad face plate. They are being prepared with electron beam welded inserts that leave a small cavity behind them to allow the fiber introduction.
The present paper describes the implemented technical solutions and the first results of the use of these technologies.

Speaker: Mr Frédéric D'Hautcourt (ARCELORMITTAL INDUSTEEL)

106 BORON IN CASTING POWDER: INSIGHTS FROM PROSIMET STUDIES

Fluorine has been widely used in continuous casting mold fluxes due to its ability to reduce surface tension, lower viscosity, and decrease melting temperatures. However, its dissolution in secondary cooling water leads to hydrofluoric acid formation, posing significant environmental and safety hazards. As a result, research has focused on alternative fluxing agents, with borate compounds emerging as a promising substitute due to their ability to form borosilicate structures.
The present work consolidates findings on the role of boron in mold fluxes, focusing on its effects on viscosity, structural behavior, and environmental impact. Studies indicate that boron can act as either a network former or modifier depending on its concentration and interactions with elements such as calcium and sodium. The viscosity and structure of borosilicate-based fluxes have been analyzed using high-temperature viscometry, solid-state NMR, Raman spectroscopy, DSC, XRD, and laser flash analysis. Results show that viscosity initially decreases when replacing CaF₂ with B₂O₃ but increases at higher B₂O₃ concentrations due to changes in tetrahedral borate (3D) structures, which require cationic support, particularly from sodium. ¹⁹F NMR analysis suggests that fluorine selectively interacts with sodium, disrupting tetrahedral borate formation.
Additionally, the dissolution of boron from overcooled slag glasses into secondary cooling water has been assessed using ICP-OES to evaluate its environmental implications. While boron-containing mold fluxes show potential as low-fluorine alternatives, their long-term stability, crystallization behavior, and industrial performance require further investigation.
Overall, boron-bearing mold fluxes provide a viable pathway toward reducing fluorine-related pollution while maintaining effective mold flux properties. However, further research is needed to optimize their composition and industrial applicability in order to control all the possible environmental issues.

Speaker: Marco Alloni (Prosimet S.p.A.)

107 Advancing Mold Monitoring by Integrating Thermal Analysis and Material Insights with respect to the hot crack susceptibility

This paper is part of the work on the EU funded RFCS project SHELL-CRACK that seeks to improve the as-cast slab quality of the shell in continuously cast semis through innovative strategies to control crack formation and microstructure evolution. Cracking initiation and propagation mechanism is a very complex phenomenon and depends on many factors, such as microstructure, cooling rate, cooling homogeneity, mechanical stress, thermal contraction etc. It is therefore very important to develop a quantitative measure, such as cracking index to assess the susceptibility of a solidifying strand to crack formation during the casting process. The objective of this paper is to contribute to a global continuous casting crack index from the mold monitoring perspective.

Building on previous research, such as the investigation of strand surface defects through mold instrumentation and modeling, our study further explores the role of mold thermal monitoring in optimizing slab quality. Current research uses data mining techniques on temperature signals from the HDmoldTC mold monitoring system at ArcelorMittal Avilés to enhance the mold monitoring process by integrating advanced thermal analysis techniques and material property model. Particular attention is given to the development of enhanced temperature variation coefficient formulas and their correlation to thermal contraction and hot crack susceptibility. The analysis reveals that certain steel grades, in particular microalloyed heavy plates and medium carbon steels near the critical peritectic range, show significant variability in thermal contraction and hot crack susceptibility due to compositional variations.
The presented research contributes to the development of a more comprehensive and predictive crack index leveraging the complex relationship between chemical composition, thermal behavior, and material properties. This thesis not only promotes the theoretical understanding of crack formation but also offers practical insights into the improvement of process stability and product quality in the steel industry.

Speaker: Mr Artemy Krasilnikov (SMS group)

108 Cu+: A New Standard in Slab Mould Plate Design for Cost-Effective Steel Production

Steel manufacturers are increasingly challenged to deliver high product quality while simultaneously lowering operational costs to remain competitive. One key metric in evaluating performance is the cost per ton of steel produced.
This work aims to develop a mould plate design that provides measurable advantages in terms of cost per ton, without compromising on heat conditions, quality or reliability. By rethinking existing designs, we seek to offer a solution that enhances economic and operational efficiency in continuous casting.
This work began with an in-depth analysis of current market demands, which clearly indicated the need to extend lifetime in order to address increasing cost pressures.
Several conceptual approaches were evaluated to achieve this goal, including the use of thicker coatings and increased overall plate thickness. Ultimately, a decision was initially made to focus on a thicker mould plate, enabling more rework cycles and an increasing operational lifetime.
The key challenge of increasing plate thickness was presented: it leads to varying cooling conditions between the beginning and the end of the mould plate’s lifetime. As a result, the steel solidifies differently over time, potentially impacting process stability and product quality.
To overcome this issue, we developed the concept of variable cooling channel geometries, implemented using interchangeable filling pieces. They are replaced once during scheduled maintenance, enabling two distinct cooling geometries over the plate's lifetime. This approach ensures that known and stable cooling conditions are maintained at all times.
Thermal simulations confirmed that this approach can theoretically enable an increase in plate thickness of up to 50%, directly translating into longer plate lifetime. Based on these findings, a mould plate design was developed according to the new Cu+ concept.
Finally, the performance of the Cu+ mould plate is benchmarked against existing standard plate designs, highlighting its advantages in both longevity and economic efficiency.

Speaker: Dr Alexander Beel (cunova GmbH)

109 Case study on the improved reliability and efficiency of the HD moldFO+ fiber optic mold monitoring system

The implementation of the optical fibers revolutionized mold monitoring and provides signals with previously unattained resolution and quality. The biggest challenge with this technology is to connect fiber optics in harsh environments because dust and dirt can easily block the optical connector and cause signal loss. The newly upgraded HD moldFO+ brings with it important progress, including a permanent connection between the optical fiber and the evaluation unit as well as the electrical cabling to the PLC room, which increases plant availability and operational reliability.

A case study by a Japanese customer shows the advantages of the HD moldFO+ system. According to customer reports, the copper plates in the molds can be remachined and plated more than ten times while the functionality of the optical fiber equipment remain maintained. The durability and cost-effectiveness of the system can thus be demonstrated. The HD moldFO+ system uses ultra-compact interrogators housed directly on the mold. This configuration enables the transition from optical to more resilient electrical connections, effectively reducing dust and moisture ingress problems common in casting environments.

The compact design of the system and the improved sensor bundling facilitate handling and maintenance, thus ensuring the longevity of the fiber optics. These improvements not only simplify retrofitting and new plants, but also offer a robust solution for continuous casting, which is also reflected in the positive results of the Japanese customer. In this way, the HD moldFO+ represents a significant advance in mold monitoring technology and offers higher performance and reliability.

Speaker: Stephan Six (SMS group)

Refractories & Sustainability

2.2.3

Convener: Roberto Peri

110 Highly efficient technologies for increased yields in steelmaking processes and reduced environmental impact

The HIYIELD project leverages advanced technologies to promote circular economy practices in steel production by increasing scrap utilization and reducing dependence on pig iron from coal-fired blast furnaces. The project encompasses three industrial demonstration cases, each addressing a critical aspect of scrap processing and integration.
In Demo Case 1, industrial-scale trials were conducted to optimize scrap sorting through mechanical, physical, and sensor-based separation techniques. A hammer mill-based process achieved a ferrous yield of 99.5% purity, with a magnetic separation efficiency of 91%. Additionally, a laser scanner system enabled real-time scrap volume estimation, facilitating improved charge optimization for steelmaking. A deep learning (DL)-based classification model was developed to enhance automated scrap recognition by integrating electric arc furnace process data and real-time imaging for improved material characterization.
Demo Case 2 focused on optimizing the identification, classification, and processing of pre-consumer scrap through industrial trials employing X-ray fluorescence (XRF)-based separation and DL-based models. The implementation of the Digital Scrap Information Card (DiSC) enabled efficient data exchange between suppliers and consumers, ensuring precise scrap tracking. Furthermore, a DL-based scrap identification system utilizing self-supervised learning models was developed, enhancing automated scrap classification and assessment.
In Demo Case 3, a high-speed sampling (HSS) and analysis system was developed for direct on-site characterization of liquid steel. Comparative analysis between HSS and conventional lollipop sampling methods demonstrated strong agreement in chemical composition, validating the accuracy and reliability of the HSS system for real-time steel characterization.
The findings of the HIYIELD project support increased scrap utilization in steelmaking, improving process efficiency while reducing environmental impact. These advancements contribute to the European Union’s long-term decarbonization and circular economy objectives.

Speaker: Prof. Björn Glaser (KTH)

111 Enhancement of tramp elements removal from liquid iron by molten oxysulfide electrolysis

The recycling of steel as a secondary raw material in low-carbon steelmaking is limited for maintaining sufficiently low content of tramp elements (TEs) in steel products, as TEs contaminate molten steel during the remelting process in the electric arc furnace (EAF). A molten oxide electrolysis (MOE) has been applied for metal production and new refining processes. A recently proposed electrorefining process using an oxysulfide electrolyte was shown to remove carbon and Cu simultaneously from molten iron. In this study, anodic polarization was performed at the interface between molten slag with added iron sulphide and molten iron containing typical TEs such as Cu, Sn, Ni, and Cr, and the possibility of simultaneous removal of TEs from molten iron was explored. The metal (Fe-0.5 wt%Cu-0.2 wt%Sn-0.2 wt%Ni-0.2 wt%Cr) and the slag (52.25 wt%Al2O3-23.75 wt%CaO-10.45 wt% SiO2-8.55 wt%MgO-5.00 wt%FeS) were melted at 1873 K in an Ar atmosphere with various oxygen partial pressures, and experiments under several conditions were conducted for 3600 s each. After the experiments, the metal was quenched and analyzed for Cu, Sn, Ni, and Cr concentrations using ICP-AES. In the experiments under two conditions: “constant potential electrolysis at +1.0 V vs. Mo” and “no electrolysis”, the concentrations of Sn and Cr decreased from the stocking concentrations to 0.043 and 0.072 wt% for constant potential electrolysis and 0.054 and 0.087 wt% for no electrolysis, respectively. There was almost no change in the concentration of Cu and Ni. It was found that iron sulphide added molten slag enhances simultaneous removal of at least Sn and Cr by electrolysis.

Speaker: Masahiro Ambiru (Tohoku University)

112 Low Carbon Footprint EAF Refractories to support Scope 3 emissions reduction and the overall European green steel transformation

The steel industry, as one of the main contributors to the CO2 emissions worldwide, is called to make efforts to reduce its carbon footprint. The green steel transformation is focussing on Scope 1, mainly by substitution of the Blast furnace, and Scope 2, by usage of only electricity coming from green sources or by substitution of Natural gas by green hydrogen. In regard of Scope 3, steelmakers have shown an increased interest in the last year as a mean to further optimize their carbon footprint.
RHI Magnesita, as a global supplier of refractory materials and solutions, is fully committed to support this transition by focusing on refractory circular economy (i.e eliminating refractory landfill) and reinforcing its Research & Development activities to increase circular raw material (CRM) in all its products.
This article aims to present best practice examples on low Carbon Footprint engineered refractory concepts for the EAF lining wall & hearth, also considering the refractory maintenance. RHI Magnesita’s offering already meets the challenge of increasing CRM usage while maintaining the required performance.

Speaker: Uxia Dieguez Salgado

113 Recent Advances in Refractory-Maintenance and Safety for Steel Plants with the help of 3D-Laser-Scanning, Digitalization and Gunning-Robot-Systems

Steel producers face increasing pressure to cut costs, lower CO₂ emissions, and enhance safety amid evolving economic and production landscapes. This paper highlights recent advances in measurement technology and digitalization that optimize safety, yield, and refractory performance in hot metallurgical vessels. Key innovations include fully automatic repair systems for electric arc furnace (EAF) refractory linings, rapid hot-condition inspection of torpedo ladles and a Steel Production Assistance System (SPAS) leveraging laser-based measurement data.
Central to these improvements is the deployment of state-of-the-art 3D laser scanning technology, capable of capturing over 10 million data points within seconds. This high-resolution data enables highly accurate assessment of refractory wear, which is then used to guide automated gunning robots for precise, targeted repairs. As a result, repair materials are applied only where needed, reducing overall refractory consumption and minimizing downtime by shortening “Power Off” periods for maintenance.
These digital solutions also support the “no person on the floor” safety philosophy, significantly improving operational safety by reducing human exposure to hazardous environments. Furthermore, integrating real-time measurement data into Industry 4.0 frameworks allows for predictive maintenance, optimized resource utilization, and continuous process improvement. Collectively, these advancements drive increased furnace availability, lower costs, reduced emissions, and enhanced competitiveness for steel producers in a rapidly changing industry.

Keywords: Laser Profile-Measurement; Refractory-Maintenance; Gunning-Robot; Safety Measures; Digitalization-Industry 4.0

Speaker: Mr Martin Welling (Minteq International GmbH)

114 Life Cycle Assessment for the electric steelmaking route in the ALCHIMIA project

The European project ALCHIMIA “Data and decentralized Artificial intelligence for a competitive and green European metallurgy industry” (GA No 101070046) gathers academic and industrial partners in the steelmaking sector to optimize steel scrap use in the Electric Arc Furnaces (EAF) and the Ladle Furnace (LF) operation. The project aims to develop a Federated Learning informatic architecture integrating computational models based on data science.
Within this framework the Life Cycle Assessment (LCA) methodology serves two key roles:
• Establishing a baseline eco-profile for three CELSA Group steelmaking facilities (called Factory 1; Factory 2, and Factory 3). A cast-iron production plant (Fonderia di Torbole, FdT) was also assessed, but is beyond the scope of this contribution.
• Providing environmental impact factors for a multi-objective economic and environmental optimization model to reduce costs and impacts compared to the baseline.
A primary data collection campaign, conducted with CELSA process engineers, enabled the development of Life Cycle Inventories (LCIs) for EAF and LF operations. These data regard the consumption of materials and energy and the production of waste and pollutants. Since the focus of the project is on steel scraps, detailed data about the amount and composition of the scraps have been collected.
The baseline model has been firstly used to identify the major environmental hotspots of the processes. In particular, the results show that the use of ferroalloys, and more in general of tapping additions, represents the main contributor to the environmental impact of the steelmaking plants. Moreover, electricity consumption turns out as another major environmental hotspot. The environmental burdens associated with direct emissions, waste management, water consumption are also accounted for. Developing an optimization model is the focus of ALCHIMIA’s second phase, currently underway. Once finalized, results will be compared to the baseline to quantify the potential environmental benefits of optimization.

Speaker: Dr Federico Rossi (Sant'Anna School of Advanced Studies)

115 INNOVATIVE APPROACH IN STEELMAKING REFRACTORY APPLICATIONS

The challenges in the field of electric steelmaking have increased in recent years, especially in terms of the rising quality requirements of the steels to be produced.
These challenges have not only grown, but have also significantly changed due to various factors such as sustainability considerations and carbon footprint. Therefore, some processes, e.g. desulphurization will be shift from primary steelmaking to the ladle metallurgy, which causes intensive slag-metal interaction linked with higher corrosion and erosion of refractory materials.
Additionally, the competitive pressure on European steel producers, especially from the Asian market, is constantly increasing, making it necessary to increase steel production efficiency. In addition to energy prices or scrap and raw material availability, refractory products are also key factors influencing efficient, safe, and effective steel production.
In collaboration with various customers, we recently developed numerous solutions aimed at simplifying lining work, reducing downtime as much as possible, and increasing the safety of refractory linings in operational use.
In the field of the electric arc furnace, prefabricated slag door elements have been successfully tested and introduced. Also prefabricated blocks have been successfully tested and introduced for the taphole area.
To increase operational safety of ladles, tongue-and-groove bricks have been introduced in permanent lining. This significantly extends the service life of the lining and, through careful material selection, also improves the breakthrough prevention properties.
For the AOD converter, our comprehensive refractory solutions have been complemented by specialized logistical strategies designed to simplify material handling and improve installation efficiency.
This paper provides a detailed overview of these innovative solutions and presents practical results.

Speakers: Mr Andreas Viertauer, Mr Bernd Buchberger

116 Metallic Elements Dissipation Avoided by Life cycle design for Steel – MEDALS project

The use of recycled scrap instead of iron ore is a key strategy for the steel industry to reduce carbon emissions and its reliance on critical raw materials. With the growing demand for scrap, it is becoming increasingly important to handle lower-quality steel scrap effectively. Contamination by unwanted tramp elements, such as copper and tin, can pose significant challenges in producing high-quality steel. Also important is the recovery of valuable alloys by scrap sorting.
To address these issues, the MEDALS project has been initiated to enhance the integrated value chain of scrap-based steel production by developing innovative technologies for scrap sorting, tramp element removal, and recovery and valorization of metal-containing residues. As part of MEDALS, advanced sensor configurations and data-driven models will be implemented to enable automated scrap sorting and separation. Additionally, novel pyrometallurgical methods will be introduced to reduce tramp element content in liquid steel.
Advanced technologies will be also developed to valorize steelmaking residues. Laboratory experiments, supported by thermodynamic and kinetic modeling, will be conducted, and findings will be validated at industrially relevant environment.
Optimizing end-of-life product grouping will be prioritized to maximize alloy recovery while minimizing tramp element contamination. An assessment of improvements linked to better practices will be conducted to evaluate the environmental and economic impact of the proposed solutions. Overall, the initiatives within MEDALS aim to promote sustainable practices in the steel industry and foster a circular economy.

Speaker: Prof. Björn Glaser (KTH)

Rolling Mill Technology & Process Optimization

3.1.1

Convener: Silvia Barella (Politecnico di Milano)

117 SBQ Sizing - Free of charge

In the field of Special Bar Quality (SBQ) production, decades of evidence indicate that a sizing block makes a decisive difference in the total performance of each rolling mill. This is valid for green field projects as well as for modernization projects. The so-called 'sizing block' reflects a significant advancement - traditionally aimed at substantially enhancing product quality in long-product operations.

But, whereas in the past a sizing block was purely considered for sizing, nowadays, a sizing block is known to substantially influence the overall performance of each rolling mill with regard to productivity by increased flexibility. This is also the basis for the return on investment. Sizing comes along almost free of charge. What was once all about achieving tight tolerances and highest quality has now become almost a given. In today’s competitive and dynamic environment, flexibility has emerged as another key feature. Merely rolling the best product is no longer sufficient – it’s about producing the best product in the most flexible process to operate the rolling mill highly profitably.

Recently, SBQ mills have increasingly incorporated tailored sizing block solutions, to optimize their production outlets. This reflects the versatility and adaptability of this type of equipment. As those projects of leading steel producers underline, the ongoing advancements in sizing block technology not only enhance operational efficiency but moreover open up a range of strategic possibilities for mill operators. As the industry continues to evolve, the historic role of sizing blocks is expected to further expand beyond traditional applications, driving productivity and adaptability.

This paper analyses the main drivers and motivations in line with those investments in an emerging industrial landscape from a technical viewpoint. Exemplary applications of intermediate and/or in combination with finishing blocks in rolling mills across Europe and USA and their respective benefits will be presented.

Speaker: Mr Guenther Schnell (Friedrich Kocks GmbH & Co KG)

118 Revolutionizing Triple Slitting Technology for Rebar 16mm in the rolling and groove process design: QATAR Steel & POMINI Long Rolling Mills technologies

The demand for increased productivity, cost efficiency and reduce energy and environment impact in the steel rolling industry has driven the adoption of innovative technologies.
Triple slitting technology is a game-changing method in rolling processes, particularly for rebar sizes over 14 mm.
So, the intention of this paper is to explore the implementation of triple slitting technology which enables rolling mills to significantly enhance production rates while maintaining product quality and in addition also to address the challenges faced in conventional rolling methods and how triple slitting overcomes these limitations as a brown field project for the first time regarding Rebar size 16 mm by 3.

The study therefore aims to retrace in detail the achievement of the following primary objectives:
• introduce and analyze the efficiency of triple slitting technology for the 16mm rolling process by a notable increase in output through simultaneous slitting and by consistent product quality meeting industry standards, with minimal deviation in dimensional accuracy and mechanical properties,
• evaluate its impact on production capacity, cost-reduction, and operational efficiency enhanced overall mill performance with a reduction in downtime and improved throughput,
• compare triple slitting with conventional rolling methods in terms of output, quality, energy savings and CO2 reducing emissions due to optimized energy usage and improved material yield

The achievement of these goals is explained by:
• Technical Analysis: Examination of the rolling mill setup for implementing triple slitting technology, including roll pass design and equipment modifications
• Data Collection: Collection of production data (speed, tonnage, material yield) before and after adopting triple slitting
• Comparative Study: detailed comparison of key performance indicators, such as production rates, energy consumption, and material efficiency, between the conventional rolling process and the new triple slitting method
• Risk Assessment: Evaluation of challenges related to wear and tear, maintenance.

Speaker: Alberto Nardini

119 Wave Control Using Machine Vision in the Finishin Mill

In the hot strip rolling process, the reheating furnace heats the slab to a suitable temperature for rolling. The roughing mill then processes the slab, extracted from the reheating furnace, into a bar, and the finishing mill ultimately produces strips of the desired size as requested by the customer. In the cooling section, the material is processed to satisfy the customer’s required properties, and finally, the downcoiler coils the strip to produce the hot-rolled coil.

Production automation and enhancing product quality have always been key objectives pursued by steel companies. With the increasing demand for higher-quality hot-rolled strip shapes, strip flatness variation during rolling in the finishing mill has received significant attention and should be considered in online strip shape control.

Strip flatness control in the hot rolling process is a critical control for preventing defects and improving flatness during rolling. This process typically involves controlling gap leveling or benders, with the control often performed manually by operators through visual observation.

In this study, we aim to improve the waves generated during the rolling process by using machine vision to measure and quantify the waves. Additionally, we seek to develop a control logic to manage these waves in real-time during rolling.

Ultimately, the objective is to automate the previously manual measurement and control processes, thereby resolving the associated issues.

Speaker: jinwoo jung (hyundai-steel)

120 The best knows no limits! It’s time to challenge the ESP sequence lengths

Arvedi ESP (Endless Steel Production) has transformed the steel industry by integrating continuous casting and direct hot rolling into an ultra-compact process. This innovation has introduced the endless Hot Rolled Coil (eHRC) as a new market product with unprecedented geometrical tolerances and mechanical uniformity. However, ESP production follows casting sequences, which are interrupted from time to time for re-stranding operations. Currently, these production sequence on ESP lines are typically lasting for 8-12 hours. The limiting factors are the lifespan of critical components like work rolls, Submerged Entry Nozzles (SEN), and tundish wear linings. This paper describes new methods and technological advancements that extend the sequence length to 16-24 hours and beyond. Extending the sequence length boosts production efficiency, reduce operational costs, and improve competitiveness for ESP users. These advancements enable continuous production of the most complex product mix on thin slab casting and rolling plants, while preserving the core features of Arvedi ESP lines, such as zero-carbon emission hot rolling and high-quality coils.

Speaker: Kerstin Baumgartner

121 The application of bar cooling technology to plate mills for throughput and utilization improvements

Recent trends in plate steel production have seen a focus on maximizing mill productivity. Plates that are produced using a controlled rolling strategy usually have a pause in the rolling sequence. This hold time can be extended based on the process parameters and can significantly contribute to the overall production time for a single plate and reduce mill productivity. The application of water cooling to the semi-hot rolled plate, or transfer bar, increases the rate of heat removal during the hold period. The result is that the temperature of bar is reduced faster, allowing rolling to resume earlier and mill productivity to be recovered.
This paper describes a recent application of Bar Cooling technology at the plate mill line at Hyundai Steel Corporation’s Danjing Works. Hyundai and Primetals Technologies worked closely to install the system during a single shutdown. Startup and commissioning to full production and final acceptance tests was carried out over a 6-week period.
A description of the process, including the Bar Cooling System, the principles of water cooling during high temperature rolling and associated automation is provided. A flexible cooling strategy that determines the total cooling time by modifying the cooling speed and the number of cooling passes was implemented. The total cooling time was modelled to include the recovery time to a maximum equalization temperature prior to the resumption of rolling.
This paper also demonstrates the importance of advanced model-based automation to calculate the temperature-time evolution for thick transfer bars with a detailed knowledge of the water to steel surface heat transfer coefficient. This is coupled with a Level 1 automation solution to deliver the tracking and sequencing required for accurate control. Finally, off-line simulations of the bar cooling process are carried out using a Digital Twin with key results from these simulations presented and discussed.

Speaker: Dr Ian Robinson (Primetals Technologies Ltd)

122 Smart controlled actuator to homogenize the temperature of the transfer bar

An RFCS funded project, SmartCool (RFCS-PDR 101057274) has been launched together with major European steel producers and research centres. The aim of this project is to develop a selective transfer bar cooling that is intelligently controlled to correct in real time transfer bar temperature distortions during production. A step by step approach has been initiated at the design phase and various laboratory characterization trials have been conducted with small scale and full scale prototype headers before moving to the industrialization phase.

At the time of submitting the abstract, a newly developed selective cooling header has been installed online, in the hot strip mill of ArcelorMittal Ghent and commissioning trials are on-going. During the next months, an intensive test schedule will be performed to evaluate the selective cooling performance and effectiveness to correct the temperature homogeneity of the transfer bar.

A more homogenous transfer bar temperature over the width will be a huge improvement for the mastering of strip steering at the finishing mill. It will reduce the occurrence of rolling incidents and will contribute to an improved shape control (flatness) and more homogeneous final material properties which are particularly important for AHSS production.

Speaker: Pepijn Adriaen (CRM Group)

123 A Study on enhancing accuracy of AI-based RDT automatic control in hot rolling process

In the hot rolling process, precise control of dimensional accuracy and material properties in steel plates is essential for performance and cost efficiency. However, increasing customer demands have underscored the importance of surface quality. A key determinant of surface quality is the Roughing-mill Delivery Temperature (RDT), which significantly influences scale formation and surface defects.
To address this, we developed an AI-based model for RDT prediction and optimized Roughing-mill Scale Breaker (RSB) patterns. Using the XGBoost algorithm, the model integrates process parameters, including slab dimensions, rolling load, chemical composition, reheating furnace temperature, and RSB patterns. The initial model exhibited relatively high Root Mean Square Error (RMSE), which was inadequate for industrial application. Further refinements, including feature engineering and hyperparameter tuning, improved predictive accuracy. The enhanced model achieved a lower RMSE, leading to more precise RDT predictions.
However, in dynamic industrial settings, data drift remains a challenge, as process variations can degrade model performance over time. To mitigate this, we integrated continual learning and drift detection mechanisms, enabling proactive model adaptation. A hybrid approach, combining concept drift detection (ADWIN, Page-Hinkley Test) with incremental model updating, ensures sustained predictive accuracy. Additionally, uncertainty-aware learning techniques help assess prediction reliability, guiding retraining strategies. These enhancements enable a robust AI-based RDT control system to dynamically adapt to evolving production conditions. Future research will extend its application to diverse steel grades and integrate it into a smart manufacturing framework, advancing intelligent process control in the steel industry.

Speaker: Daeho Yun (Hyundai Steel Company)

Surface Technologies

4.3.1

Convener: Giovanni Bolelli (Dipartimento di Ingegneria "Enzo Ferrari", Università di Modena e Reggio Emilia)

124 Improving sustainability of Cold Rolling of Low-Carbon Steels via Oil Free Lubricants

The European steel sector is committed to improve sustainability of the whole steel production chain, from decarbonisation of major upstream processes up to all downstream operations, including rolling. In particular, in the cold rolling process, oil-in-water emulsions/dispersions are usually applied to lubricate the cold rolling process of low-Carbon steel. Such emulsions present some drawbacks mainly related to emulsion bath maintenance, subsequent production stages and waste disposal. Past research works showed that in some application areas, Oil Free Lubricants (OFL) show lubricant properties that are comparable to conventional lubricants, while providing significant environmental benefits. The project entitled “Transfer of aqueous oil free lubricants into stee cold rolling practice” (Ref. RollOilFree II – G.A. No 101112433) aims at developing an Oil-Free Lubricant for the cold rolling process of low-Carbon steel for applications in the automotive and packaging sectors by assessing its performance in industrial conditions. To this aim, the project combines tests at laboratory scale and simulations with trials in an industrial pilot cold rolling mill and, finally, field trials at industrial scale.
The paper will overview the work which has been undertaken in the first period of the project including laboratory investigations, part of the pilot trials and the preliminary concepts for simulation of cold rolling with Oil Free Lubricants. Preliminary outcomes will be presented and discussed.

Speaker: Prof. Valentina Colla (Scuola Superiore Sant'Anna)

125 High Turbulence Pickling

In steel making, several processing steps are required to produce carbon steels strips. During the hot rolling step, the high temperature and exposure to air and humidity leads to a surface covered by an oxide. The function of the pickling line is to remove this oxide layer to be able to continue processing the steel, such as by cold rolling, welding, coating, painting. Most of the pickling lines remove the scale from the hot rolled strip using a chemical process with strong acids (hydrochloric or eventually sulphuric acid) to chemically remove the oxide. This pickling process has changed little since the year 60’s, with some incremental improvements like the incorporation of a mechanical scale breaker (bending the strip before the acid pickling), reduction of the depth of the tanks by using turbulent flows, and the introduction of inhibitors to avoid over-consumption of the steel.

An RFCS funded project named InnoPick was launched in 2023 aiming at a strong modernisation of the pickling process. It focusses on four innovative actuators: pre-heating of the strip, use of organic acids, highly turbulent pickling baths and the utilisation of abrasives particles to reach a sustainable and fast process to remove the scale from carbon steel strips. This paper will focus on highly turbulent pickling, from the design of the modules to their characterisation through laboratory trials. Finally, the paper will illustrate how high turbulence in pickling can decrease the necessary time to fully pickle carbon steel strip. Preliminary laboratory trials performed at CRM have shown a decrease by a factor between 2 and 5 while using turbulent pickling in regards of pickling time.

Speaker: Sebastien Flament (CRM)

126 Optimization of Stainless Steel Cold Rolling Lubrication Through Thermal Modeling

In cold rolling, the mixed lubrication regime is needed e.g. to avoid skidding. In fact, low viscosity oils are used as lubricants to set lubrication at the frontier of the boundary regime, promoting strip surface smoothing by finely ground rolls. This poses a risk of boundary regime interface degradation, including adhesive transfer, which may harm final strip surface quality. On the other hand, heat is generated at the contact region between the strip and the roll under two forms: friction dissipation and plastic deformation, increasing the roll and strip temperatures (up to 200 ℃ depending on the rolling conditions). In turn, temperature influences the lubricant behaviour and therefore the coefficient of friction (dual relation), especially when it exceeds the desorption temperatures of polar additives ( ~150 ℃). The effect is twofold: 1) High upstream temperature reduces lubricating film thickness, worsening boundary lubrication and dependence on additives. 2) Excessive temperature hampers friction-reducing additives, while extreme-pressure additives need significant film-forming time. In classic mixed lubrication regime theory, to predict friction in the roll bite, the mean lubricant film thickness and fractional contact area evolutions from the entry to the work and exit zones are evaluated using Reynolds equation integrated together with the theory of plastic asperity crushing. The goal of this study is to enhance these lubrication models with a roll and strip thermal model. The proposed model predicts key phenomena, including a decreasing in viscosity within the contact region, a reduction in lubrication film thickness, and an indication of transition into the boundary lubrication regime. In the latter, an estimate of the risk of loss of lubricity, adhesion and strip surface degradation is proposed, based on interface temperature and superficial plastic strain. An example of application to a typical stainless steel cold rolling schedule will be presented.

Speaker: Ms Cynthia ELHAJJ

127 Design and advantages of a hybrid furnace combining gas burners and induction heating

This study introduces a hybrid heating furnace design that integrates gas burners and induction heating to achieve enhanced energy efficiency, precise temperature control, and operational versatility. Gas burners provide high thermal output, while induction heating enables rapid, localized temperature adjustments, making the system ideal for applications such as metal heat treatment, rolling and forging. The hybrid configuration reduces heating time and energy consumption, improving overall efficiency by if compared to conventional furnaces. Advanced control systems facilitate seamless switching between gas and induction heating modes, ensuring optimal performance across diverse industrial processes. Computational modeling and experimental validation demonstrate the system’s superior thermal performance, energy savings, and sustainability, supported by features like waste heat recovery and reduced greenhouse gas emissions. This combined design offers a flexible, eco-friendly solution for industrial heating, with potential for scaling and integrating renewable energy sources to further enhance sustainability and reduce carbon footprints in manufacturing.

Speaker: Prof. Carlo Mapelli (Dipartimento di Meccanica - Politecnico di Milano)

128 Hot strip surface quality improvements by: Work roll lubrication and cooling package for hot strip mills with a new special feature for a continuous lubrication

Improving energy efficiency and product quality in hot strip mills is essential to meet
the increasing demands for modern production facilities. Primetals Technologies
developed an advanced work roll lubrication and cooling package, including the
innovative Power Work-Roll Cooling system. This integrated solution combines
energy efficient dynamic work roll cooling, advanced roll-gap lubrication, and an
innovative work roll cleaning system to deliver superior performance, reduced costs,
and enhanced energy efficiency.

The Power Work-Roll Cooling system can achieve up to 70% energy savings
compared to conventional cooling methods by operating at significantly lower
operation pressure (4 bar vs. 13 bar) while maintaining high cooling efficiency. Solidjet nozzles are providing a concentrated coolant flow that enhances heat transfer
and overcomes the "pool effect," which may reduce cooling efficiency of traditional
systems. Additionally, the dynamic cooling enables a flexible and precise thermal
crown control by adjusting flow rates across the entire length of the roll barrel,
ensuring optimal strip contour and flatness. An additional key feature is the new
“WRL NC: Work Roll Lubrication Non-Cooling” solution to reduce roll forces by up to
20%, achieving further energy reduction, excellent strip surface quality and reduced
work roll wear.

The package also includes a unique feature: an innovative work roll cleaning
solution, that removes residual oil on the work roll surface between strips, enabling
work roll lubrication over the whole strip length. This synergy of the sophisticated
cooling, lubrication, and cleaning arrangement ensures consistent quality over the
entire strip, reduced operational costs, and enhanced sustainability for modern hot
rolling mills.

These developments represent a major jump forward for hot strip mills, combining
energy efficiency with exceptional operational performance to address the evolving
challenges of both high-quality and high-capacity steel production.

Speaker: Simon Mittlböck

129 X-Pact® Solid Control – process optimization, quality control and root cause analysis in case of abnormalities in the cast product

X-Pact® Solid Control is the SMS group's secondary cooling model for slab, thin slab, bloom and billet continuous casting plants.
It consists of a "process package" that is fully integrated into the manufacturer’s plant automation and a "technology package" that helps the metallurgist to find the right process parameters before one ton of liquid steel flows into the mold.
The aim is to show the advantages of how X-Pact® Solid Control:
- helps to find the right process parameters for special steels, such as increasing the globulitic fraction in silicon grades,
- is used in the casting process to increase production through targeted temperature control, or to save energy during hot charging to improve the CO2 footprint,
- provides data for quality control to detect anomalies using soft sensors,
- can be useful to find the origin of cracks in case of defects in the cast product using HD scan and the Defect Analyzer.

Speaker: Mr Ronald Wilmes (SMS group)

19:00 Get-together - Meet&Greet

Poster Session

130 Exploring the Potential of Electric-Arc-Furnace Slag in Sustainable Crop Production

Circularity necessitates efficient utilization of by-products from diverse industries. Steel slag, one of the by-products generated through steel manufacturing, has the potential to be used in different areas, including but not limited to agriculture. In our study, the impact of electric-arc-furnace (EAF) slag on growth and mineral composition of model crops has been investigated in alkaline and acidic soil types under greenhouse conditions. Mineral composition and physicochemical properties of EAF slag were determined prior to pot experiments. Steel slag amendment remarkably improved the growth of wheat by up to 78% over control in acidic soil. It ensured significant enhancement in shoot P, K, Zn, and B levels, particularly in acidic soil. Moreover, the yield and nutritional quality of the grain positively responded to slag amendment as well. The lettuce growth, on the other hand, was improved by 400% compared to control in response to steel slag application in acidic soil. Mineral composition of lettuce was also improved by slag amendment in terms of K, Ca, and Zn concentrations. There was no significant increase in the concentration of potential toxic metals like Cd, Cr, V, or Pb observed in any of the model crops as a result of slag application. Furthermore, 31% and 60% decreases over control in the shoot Cd level were achieved by steel slag treatment in alkaline and acidic soil types, respectively. Obtained results demonstrated that steel slag could enhance the yield and nutritional quality of the grain and the harvestable biomass of lettuce through improvements in soil properties. EAF slag proved to be a potential alternative to chemical fertilizers, which cause significant amount of CO2 emission during their production. The long-term effect of steel slag on soil and different plant species should be tested to determine the safety of the material, especially under field conditions.

Speaker: Rifat Bugra Bildiri (Institute of Biotechnology, Gebze Technical University, Kocaeli, Turkiye)

131 New generation of Admite rolls using in Finishing Stans of section mils

The hardness of adamite roll materials for hot work rolls depends on
their microstructures; the amount and hardness of coarse carbides and the
hardness o f matrix. The high-hardened adamite roll materials are excellent
in wear resistance when the amount of coarse carbides is about
8 %, but the wear resistance deteriorates when the amount of coarse carbides
exceeds a critical level.
The reason is considered to be as follows : As the volume of coarse
carbides increases, the spacing between coarse carbides decreases and the area of coarse carbides in contact with hot strip surfaces also increases, to induce a partial disintegration of brittle coarse carbides. The high-hardened adamite rolls with about 8 % of coarse carbides have a hardness from Hs 65 to 70 and can be used for hot work rolls with satisfactory results.

Speaker: Adel Sheikhhosseini (Behin Industrial Group)

132 Optimizing Biomass Gasification-Driven Carburization for Carbon-Neutral Hydrogen-Based Steelmaking

Global steel companies are shifting from coal and natural gas-based production methods to hydrogen-based systems in pursuit of carbon neutrality. However, transitioning from coal to hydrogen significantly increases electricity consumption. To address this challenge, it is imperative to expand renewable energy resources, promote the supply of green hydrogen, and reduce its cost. In this context, we propose the development of a carbon-neutral carburization process that utilizes biomass to support the expansion of renewable energy. The carburization process is critical to the production of direct-reduced iron (DRI), as the carbon in the DRI provides chemical energy input to the electric arc furnace (EAF), thereby reducing the electric power requirements. Specifically, the carburization process in the form of cementite has been shown to yield a higher recovery in the electric arc furnace (EAF). The presence of high-carbon DRI in the cementite form has been shown to enhance DRI stability and EAF productivity.

In this study, we employed biomass gasification which does not produce carbon footprint of product(CFP) within carburization technology. Hydrogen-reduced pellets were carburized using bio-syngas, and we examined both the carbon content and its form (cementite/graphite) in accordance with the influencing factors associated with carburization.
It was observed that the temperature dependency of the carburization process varied with the contents of the primary carbon-based gases in the bio-syngas, attributable to differences in the reaction heat. Additionally, byproducts such as H₂ and CO₂ were found to influence the carburization process differently.

The study also revealed that both the carbon deposition and form were strongly dependent on the reaction time. Prolonging the deposition time beyond the optimal duration led to cementite decomposition reactions, resulting in the formation of graphite (i.e., dust). Consequently, optimal operating conditions were derived to maximize carbon yield while effectively suppressing cementite decomposition reactions.

Speaker: YUBIN LEE

133 SMS ZERO2Flame HY2 burner for reheating furnaces

R&D in SMS Group focused on the study and testing of an innovative lateral burner for reheating furnaces, able to work in flame and flameless mode, with hydrogen content in the natural gas-H2 fuel blend up to 100%vol. H2, and oxygen (O2) content in the comburent flow up to 50%vol. O2. An intensive CFD simulation campaign was conducted, with the aim of defining an optimized burner design, able to work efficiently in all the mentioned conditions. In flame mode, the oxygen addition led to a reduction of the combustion-reaction zone, a detached flame and a strong temperature gradient in the flame, with increasing trend of the maximum temperature of the flame, due to the increase of the gases reactivity. The OH- radicals concentration exhibited an increase, in agreement with the high NOx values. The results in flameless regime manifested an opposite trend, with increasing the oxygen content in the comburent, with a decrease of the temperature values and an accentuated homogeneity in the heat release in the furnace chamber.
The experimental tests highlighted the predominant and opposite effects of oxygen and hydrogen contents, on the SMS ZERO2Flame HY2. In flame mode, NOx emissions increased with the hydrogen and oxygen contents. The optimized burner design allowed to obtain extra-low NOx emission results in flameless mode, below 80 mg/Nm3 at 3%vol. O2 DFG in all the tested conditions. In “mild” regime both hydrogen and oxygen contents’ increase lead to a NOx emission reduction, with a uniform heat release in the furnace chamber. The developed oxygen supply system granted an optimized fuel-comburent mixing, combining both the beneficial effects of the flameless combustion and the oxygen-enhanced combustion. SMS ZERO2Flame HY2 burner is a flexible solution for multi-fuel hydrogen-ready oxygen-enhanced requirements, able to offer extra-low pollutants production and an optimized heat release for reheating furnaces.

Speaker: Mr Umberto Zanusso (SMS group)

134 The Effect of Crystallization Temperature on the Properties of Silicon Manganese Slag Cast Stone

Similar to the formation process of nature granite, the molten slag is directly prepared into large volume cast stone, where the stress is affected by the mechanical and thermal expansion properties of its crystallization, which is easy to crack and lead to cracking. The phase composition and thermal expansion properties of the silicon manganese slag cast stone prepared at different crystallization temperatures were studied by DSC, XRD, SEM and CTE. The experimental results show that silicon manganese slag as the main raw material with 8% modification additives in it had been converted into large volume cast stone with qualified properties after remelting at 1500℃, casting, and curing at crystallization temperature (900℃, 1000℃ and 1050℃, respectively), and annealing at 700℃. Cast stone sample CT-900 has the best compression performance, which may be related to crystal size and structure. The crystallization interval of silicon manganese slag cast stone is 900~1100°C, and the main crystalline phase is augite and akermanite-gehlenite. CT-900 is mainly composed of augite and amorphous phase. With the increase of crystallization temperature, akermanite-gehlenite begins to precipitated in amorphous phase. At the same time, it becomes larger with augite crystal and its crystal structure becomes tighter, but its compressive strength becomes worse. Because CT-900 contains more amorphous, crystal phase transformation occurs at 1050~1100℃, and akermanite-gehlenite is formed in the residual glass phase, resulting in a large expansion coefficient. CT-1050 has a tighter crystal structure than CT-1000, resulting in a greater coefficient of thermal expansion. It shows that the lower the crystallization temperature and the absence of amorphous phase, the lower the thermal expansion coefficient of the sample. At the same time, for a sample, a smaller cooling rate is conducive to a lower thermal expansion.

Speaker: Mr Yi Huang (University of Science and Technology Beijing)

135 Advancing Sustainability in Continuous Casting of Steel Strategies for Productivity, Traceability, and Waste Reduction

Strategie di produttività, tracciabilità e sostenibilità con riferimento ai cristallizzatori per la colata continua dell'acciaio.

Speaker: Angelo Naclerio

136 Prediction and controlling of strip buckling during industrial continuous annealing process

During the continuous annealing process in the steel rolling heat treatment procedure, the occurrence of buckling in strip is a common issue, especially in the heating and soaking zones. The lateral distribution of stress state of the annealing strip is the essential factor resulting in the phenomenon. However, accurately predicting it is very difficult. Many factors influence the stress state of strips subjected to industrial continuous annealing processes. Therefore, this paper proposes a stress lateral distribution calculation model for the industrial continuous annealing process, the mechanism of the buckling phenomenon is analyzed, and feasible control means are proposed. The mechanism and influencing factors of strip buckling are discussed in detail. A prediction model of strip buckling position during the continuous annealing process is established. It considers the differences in the stress characteristics of the strip at different positions. This model quantifies the influential factors such as transverse temperature differences, roll geometry, and set tension stress on the occurrence of strip buckling. Moreover, an online "Strip Buckling Position Predicting Software" is developed, which not only predicts the potential buckling positions but also provides feasible solutions. The software provides a theoretical basis for the intelligent continuous annealing process and the development of new steel grades.

Speaker: Dr Ruowei Li (Department of Mechanical Engineering, Politecnico di Milano, Milano, 20156, Italy)

137 Effect of Magnesium Deoxidation on Non-Metallic Inclusions in Austenitic Stainless Steel

Austenitic stainless steel (ASS) is widely utilized in various industries owing to its exceptional corrosion resistance, heat resistance, and mechanical properties. Achieving ultra-high cleanness is critical to obtaining these desirable properties. To enhance cleanness, ASS is typically produced through vacuum induction melting (VIM) and/or vacuum arc remelting (VAR) processes, with Al or Si commonly employed as strong deoxidizers. Nevertheless, non-metallic inclusion (NMI) such as alumina, spinel, and aluminosilicate form because of impurity entrainment, reoxidation of molten steel, or refractory-metal reactions during deoxidation. These inclusions can adversely affect steel productivity and quality. On the other hand, oxide metallurgy described the positive utilization of fine oxide inclusion particles to control the grain size of solidified steel. Considering both effects, it is essential to design an optimal deoxidation practice to control the number, size and phase of NMI particles.
In the current study, therefore, a magnesium (Mg), a strong deoxidizer in the form of a Ni-Mg alloy, was used to deoxidize ASS melt in an alumina crucible. The effects of Mg content on the area fraction, number density, and phase of inclusions in the molten steel were investigated. The results demonstrated that both the number density and area fraction of NMI decreased with increasing reaction time and Mg content. Moreover, the inclusion phase transition occurred from ${\text S}$${\text i}$${\text O}_2$-rich system to MgO-rich system as the Mg content increased. However, higher Mg content also led to increased Al pick-up from the alumina crucible, resulting in the formation of ${\text M}$${\text g}$${\text A}$${\text l}_2$${\text O}_4$ spinel-type inclusions through the reaction between MgO in inclusion and Al in molten steel, i.e., (MgO)inclusion+2[Al]+3[O]=${\text M}$${\text g}$${\text A}$${\text l}_2$${\text O}_4$(s) reaction.

Speaker: Min Kwan Chang

138 Development of an AI model to optimize cooling conditions for hot-rolled coils from the down coiler to the storage yard to minimize material properties deviations in high-strength steel

In high-strength dual phase steel, where phase transformation continues even after the down coiling process in hot rolling, material deviation in the hot-rolled coil occurs due to differences in cooling rates in the radial and circumferential directions during the cooling process. This material deviation leads to short-cycle hunting of rolling load during the subsequent cold rolling process, ultimately resulting in product thickness defects and reduced cold rolling productivity.
Excessive cold rolling load hunting occurs in about 50% of the coils produced, and analyzing the causes of rolling load hunting is challenging due to the numerous related variables. Our research team developed an AI deep learning model to identify the correlation between the cooling history after coiling and rolling load hunting and derived optimal cooling conditions.
The detailed implementation of this study is as follows:
1. Data Collection and Preparation: We precisely established the coil position in the hot-rolled coil storage yard and developed a detailed cooling history management database to create input variables for the AI model.
2. Quantification of Output Variables: We developed a method to accurately quantify the amount of cold rolling load hunting, which serves as the output variable of the AI model.
3. AI Model Development: We developed several AI models to clearly identify the correlation between coil cooling history and rolling load hunting.
4. Optimization and Application: We derived the optimal cooling conditions to minimize material deviation and applied these conditions in actual production sites, achieving a significant reduction in rolling load hunting to about 30% of the previous level.
This study is considered a pioneering attempt by our research team to apply an AI model that connects hot rolling and cold rolling to identify the causes of material deviation in hot rolling.

Speaker: Dr Youn-Hee Kang (POSCO)

139 Inline intermix detection by laser spectroscopy, increasing the metallurgical output in continuous casting strand.

To cast liquid steel into solid semifinished products, current steel industry predominantly relies on continuous casting process. Although 90% of the liquid steel can be cast into quality products, producers are still facing challenges to effectively determine transition zone in the casting strand. This normally happens at the beginning and end of a casting sequence as well as while transitioning between different alloys within the same sequence. Since inline monitoring is not possible, the length of this transition zone is often estimated based on experience. To avoid intermixes, large safety zones on both sides is being cutted which is either scrapped or seats in the stockyard to be sold as a downgraded product.

Laser-induced breakdown spectroscopy (LIBS) enables continuous, real-time measurement of the strand's chemical composition. This technology can precisely define the transition zone, minimizing the amount of scrapped or downgraded material. As a result, overall competitiveness of the process can be increased by boosting productivity and saving energy and resources.

Speaker: Martin Sprunk (SECOPTA analytics GmbH)

140 Technical Overview of Unique Non-Woven Process Rolls

Non-woven fabrics are surprisingly ubiquitous in daily life, appearing in everything from kitchen scrub pads and disposable floor wipes to baby diapers, building vapor barriers, and even aircraft insulation. These materials offer unique advantages in functionality, durability, and adaptability, making them indispensable across a variety of industries. One lesser-known—but highly impactful—application of non-woven materials are process roll covers for sheet finishing lines, where non-woven materials provide distinct benefits over traditional roll materials such as elastomers, urethane, and metal. However, these non-woven rolls are often misunderstood and misapplied, limiting their effectiveness and generating stubbornly unfair negative opinions.

This non-commercial presentation provides a comprehensive yet accessible overview of non-woven process rolls specifically designed for metallurgical process lines, particularly in sheet finishing applications from pickling to coating and plating. It will outline the fundamentals of non-woven roll design, production, and function, offering a clear perspective on why these materials are increasingly used in demanding industrial environments. The discussion will focus on the four (4) primary advantages that non-woven rolls offer over conventional materials, and the three (3) most common vulnerabilities of non-woven process rolls will be examined, providing a balanced perspective on their limitations and best-use cases.

Beyond process rolls, this presentation will briefly explore other applications of non-woven materials, particularly in surface cleaning and defect mitigation through enhanced friction, where they serve as innovative alternatives in metallurgical finishing. This presentation will be delivered in a straightforward, no-nonsense manner to engage both technical professionals and laypersons alike, offering a deeper appreciation for the versatility of non-woven materials in modern manufacturing.

Speaker: Mr Eric Almquist (StarTool)

141 INNOVATION IN FREQUENCY CONVERTERS TO REDUCE DOWNTIME AND IMPROVE PRODUCTIVITY IN STEEL PLANT

Steel plants are full of dust and gas and PCB has a tendency to fail if not protected properly. To avoid the downtime, it is recommended to use highest level of conformal coating to protect from dust and corrosive gases present in steel area.
Thermal management is a key criteria in steel plants. Innovation in technology has helped to segregate the power module heat from the control components, ensuring the control components don’t get heated up and the components life increases.
Additionally with an advanced thermal technology can also be used to throw out the components out of the electrical room, ensuring reduction in CAPEX and APEX cost of HVAC and reduction of CO2 footprint.
New simulation program has been invented where the product can be selected and tested in a simulation mode even before the product is produced. This can be used to simulate various situations (load cycle, overloads, temperature variant, low speed performance etc). complete plant or process can be simulated even before the model is ordered.
Intelligent frequency converters features enable the prediction and detection of early failure in stator winding, overloading, vibration and bearing of motors without any sensors or PLC.
This, when combined with remote monitoring features, can increase efficiency and reduce periodic health checkup of the motors.

Speaker: Mr Suvro Basu (Danfoss)

142 Green steel production through the Endless Bar Production process

The Endless Bar Production (EBP) process reduces energy consumption by 60% and CO2 emissions by over 90% compared to conventional methods. By combining EBP with efficient melting technologies, the environmental footprint and energy balance of steel production can be minimized. This compact process with minimum material losses lowers the conversion cost of reinforcing bars by up to 40%.
The EBP process is designed for reliability and safety, making use of long-life components and quick-change parts to maximize plant availability. Advanced, multi-level automation systems guarantee safe operation with centralized, remote supervision.

Speaker: Mr Cristiano Tercelli

143 The Pathway to Autonomous Ironmaking

Achieving autonomous operation requires automation and digitalization systems with advanced control and learning capabilities. This paper discusses key elements on the pathway to autonomous blast furnace and DR operation:
Autonomous decision-making for ironmaking operations leverages sophisticated technologies, including AI and ML, to measure, control, and optimize key parameters of ironmaking processes. Online sensors monitor raw material, process, and product parameters, providing a comprehensive digital image of the plant. This data is analyzed using hybrid models that combine metallurgical knowledge with data-driven models.
The benefits of hybrid digital twins are compared in detail to classical first principles models and pure Machine Learning models, reviewing the potential and limitations of different types of digital twins and self-learning decision-making systems.
Based on the model results, rule-based Expert Systems generate process diagnoses, triggering transparent closed-loop process optimization actions, resulting in stable, efficient, and shift-independent operation. A learning condition monitoring system assesses equipment status, supporting preventive and predictive maintenance.
The Expert System and the Condition Monitoring System both digitalize knowledge and provide actionable information—one for operation, the other for maintenance. These local optimization systems are complemented by higher-level systems that orchestrate upstream and downstream plants for production planning, overall process optimization, and maintenance management – resulting in stable, efficient, and shift-independent operation.

Speaker: Dieter Bettinger (Primetals Technologies)

144 Improvement on energy efficiency systems under volatile production scenarios

Steel production in Europe is facing several challenges nowadays. The remaining high prices for energy and the demand on steel are some of the most pressing topics for steel producing companies. Energy efficiency technologies on the production site play an important role to improve the cost structure and the CO2 footprint to keep the competitiveness in the world market alive. Waste heat usage with ORC systems is a proven solution on gas fired ovens that uses the energy from exhaust gases to produce electricity for the factory and additionally hot water if applicable.

As the volatility of the steel production volume increased significantly in the last years, also the waste heat amount is hereby strongly affected. Energy efficiency technologies like ORC must keep track with these changes to secure the profitability of their usage under the new conditions. Hereby it is relevant to improve the operating flexibility and extend the uptime to ensure cash flows.

To improve the operating flexibility of energy efficiency technologies, technical measures need to be implemented. On the example of an ORC system installed at a German steel factory, the lecture will present the executed system modifications in the last years with a significant improvement on the uptime and the output of the system.

This exemplary ORC-system is installed at a walking beam furnace and utilizes the exhaust gases send to the stack directly in the ORC system. The presentation will explain the technical improvements and will show the effectiveness of these measures based on the operational data. Moreover, the increased economic value of these measures will be highlighted by analyzing the modified limit values and the increased production feasibility. The findings of this specific example can help other steel factories on their way to reduce their CO2 footprint and increase their competitiveness.

Speaker: Jonas Oswald (Dürr Systems AG)

145 Multi-alloy production via chips compaction and hot rolling

Solid-state recycling techniques for metallic chips have been explored as a sustainable alternative to conventional remelting-based methods. The latest developments make these techniques promising in the production of bulk and dense materials, with the opportunity to obtain also multi-material components with this path. This study investigates the production of multi-alloy material through a combined process of chips compaction and hot rolling. AA6006 machined chips were used as metal matrix incorporating chips from different metal alloys dispersed within the matrix. The aim was to assess the feasibility of this approach in producing advanced multi-materials with gradient structures starting from waste materials as feedstock. The effect of key process parameters on the material’s properties was evaluated including compaction pressure, rolling temperature, and rolling reduction ratio. Mechanical properties were assessed through tensile and hardness testing, while microstructural evolution was analyzed using optical microscopy (OM), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD). Correlations between microstructural features and mechanical behavior were identified. Preliminary results suggest that this method has potential for producing high-density multi-metal materials, opening for further exploration of this technique as a versatile manufacturing approach for advanced materials.

Speaker: Mr Pietro Cetto (Politecnico di Milano)

146 Optimizing DRI Production with Lime-Based Coatings Agents

The production of direct reduced iron (DRI) is vital for the decarbonization of the iron and steel industry. However, operational challenges arise due to the pellet clustering during DRI production. This study examines the effectiveness of lime and dolime-based products from LHOIST in mitigating clustering issues under various reduction conditions that replicate current industrial DRI furnaces. By coating iron ore pellets with these materials, the formation of iron whiskers is inhibited, and particle adhesion is minimized. Preliminary findings indicate that lime and dolime coatings significantly reduce sticking, thereby improving the efficiency and stability of DRI production.

Speaker: Joyce Aderhold

147 AI-BASED SURFACE INSPECTION AND 3D PROFILING FOR QUALITY ASSURANCE IN STEEL PRODUCT GRINDING

High pressure grinding is gaining popularity and becoming the preferred method to remove surface defects from carbon steel semi-products. Reasons for selecting grinding over scarfing include for example higher flexibility of operations, optimized yield, easier and higher value recycling of the swarf, lower energy consumption and reduced carbon footprint. To ensure that ground semi-products meet the stringent industry standards there is a need to apply automated analysis and measurement technologies.

This paper will present how an AI-based surface inspection system with advanced machine learning algorithms is used to identify surface anomalies in real time. This enables early detection and corrective actions, reducing material waste and improving overall process efficiency. Additionally, the integration of 3D profiling technology enhances quality control by accurately measuring the slab’s geometry. By using laser-based scanning, the system captures the slab's profile with high precision, detecting deviations in thickness, flatness, and other critical dimensions.

Speaker: Mr Richard Sharp (Evertz Europe S.A.)

148 Green Hydrogen in Cogne

The project involves the installation of a 1 MW electrolyzer that will produce green hydrogen via electrolysis, utilizing electricity exclusively coming from renewable sources. This hydrogen will fully replace natural gas in a heat treatment furnace, marking a significant step towards cleaner industrial operations.
The electrolyzer will be powered by a newly constructed hydroelectric plant on the Dora Baltea River, with an average nominal capacity of 315 kW and a 300 kW rooftop photovoltaic system. This integration of renewable energy sources underscores the company’s commitment to transitioning toward a more sustainable energy model.
Supported by European Union funding under the NextGenerationEU program, the project exemplifies a concrete step in aligning industrial production with environmental sustainability goals. It will result in an annual reduction of 115,000 Smc of natural gas consumption, leading to an estimated decrease of 230,000 kg of CO₂ emissions per year.

Speakers: Mr Giuseppe Andrea Romeo, Matteo Diani, Vincenzo Morreale

149 Effect of slag conditions on the wetting behavior between blast furnace slag and cokes

To reduce CO2 emissions during blast furnace operation, the usage of pellets is increasing compared to sintered ore. Pellets melt at higher temperatures and have superior reducibility compared to sintered ore, which allows for a reduction in coke consumption. However, due to differences in composition between pellets and sintered ore, the Al2O3 content in blast furnace slag is increasing. Additionally, as high-grade iron ore is being depleted and its cost is rising, the use of medium- and low-grade iron ore with high Al2O3 content is expanding, leading to a rapid increase in Al2O3 content in slag. Changes in slag composition affect not only the burden descent behavior in the blast furnace but also internal heat transfer. In the lower part of the blast furnace, a coke bed exists, and the slag must pass through this layer to reach the lower zone. However, if the wettability between slag and coke is poor, slag may not descend smoothly, blocking the coke bed and hindering the upward flow of reducing gas. This can negatively impact heat transfer efficiency and operational stability in the blast furnace.
Therefore, this study aims to evaluate the effect of slag compositions, such as Al2O3 content, basicity (CaO/SiO2) on wetting behavior. To achieve this, CaO-SiO2-Al2O3-MgO-FeO quinary slag samples were prepared with varying basicity (CaO/SiO2) and Al2O3 content. Wettability between slag and coke was observed at 1550°C under a CO-N2 gas atmosphere, and the contact angle was measured using a commercial software. Through this study, the influence of blast furnace slag composition on wettability was investigated, and appropriate operational conditions may be proposed to enhance the stability and efficiency of blast furnace operations.

Speaker: Mr Hyeonwoo Shin (Dong-A University)

150 Decarbonization of Steel: Challenges and Opportunities for Modern Steelmakers and Carmakers

The steel industry contributes approximately 7-8% of global CO₂ emissions. To reduce its environmental impact, technologies for producing “green steel” are being developed, including the use of the Electric Arc Furnace (EAF). This technology uses scrap, Direct Reduced Iron (DRI), and Hot Briquetted Iron (HBI) as raw materials, managing to reduce energy consumption
(-30%) and greenhouse gas emissions (-77%) compared to the traditional blast furnace method. Additionally, EAF allows the production of various steel types and in different quantities, adapting to market demands.
However, decarbonizing the steel sector presents significant challenges. The cost of converting blast furnaces to EAF is high, making investment difficult for medium-sized companies. Furthermore, the low price of traditionally produced steel ($580-640/ton in 2025) makes it uncompetitive to increase the selling price to recover the investment.
Another issue concerns raw materials. The use of scrap requires strict control of its chemical composition to prevent the presence of residual elements (Cu, Ni, As, Sn, Mo, Cr, Zn, Pb, V, Nb), which can compromise mechanical properties. Additionally, as green steel production increases, a shortage of scrap could occur, leading to rising costs.
To address this problem, DRI and HBI are used as feedstock, replacing fossil-based reducing agents with hydrogen to eliminate CO₂ emissions. However, hydrogen is expensive and not readily available on a large scale, increasing overall production costs. Moreover, it must be produced using renewable energy sources to ensure a real reduction in emissions.
Projects such as HYBRIT® and “Safe&Clean” aim to develop steel that is competitive in both cost and performance compared to traditionally produced steel.
HYBRIT® wants to create the first zero-emissions steel using DRI/HBI and EAF and put it on the market next year. Meanwhile, the EU project aims to investigate the number of elements that decrease the material's properties through various mechanical-computational tests.

Speaker: Stefano Bucci (Università degli Studi di Torino)

151 Production conditions of porous iron whisker for the gas reforming in CRIP-D ironmaking process

Currently, the CO2 emission in ironmaking industry is one of the biggest environmental issues. To solve this issue, some alternative carbon recycling ironmaking processes such as carbon recycling BF are under development. However, those cannot achieve true carbon neutrality. Our group has suggested a new carbon recycling iron making process, CRIP-D, using carbon-iron ore composite. In this process, porous iron whisker produced from the biomass char-iron ore composite will be used for the catalyst of reforming the emitted gas from various ironmaking processes such as BF and BOF. In the gas reforming step, reverse water gas shift reaction, RWGS is used. It is known that iron has a potential as a RWGS catalyst in terms of its high selectivity and economic efficiency. However, the most effective characteristics of porous iron as a catalyst in CRIP-D is not determined. In this study, the production conditions of porous iron to draw the most effective characteristics as a catalyst in CRIP-D are investigated.
A composite sample using hematite reagent and several woody charcoals was prepared in a tablet or powder form. The molar ratio of carbon in char to oxygen in hematite was set as 0.75 and 0.8. Composite sample was heated up to the target temperature from 900 to 1100°C for 40, 90 and 120 min. The concentration of the exhaust gas from the sample during the reduction was measured by gas chromatography. In addition, microstructure of the sample was evaluated by SEM. The characteristics of woody charcoal are evaluated by TG-DTA.
The formation of porous iron whisker depended on the gasification property of charcoal such as peak temperature and hold temperature. Some sample can be seen both whisker and porous structure. It will be discussed from the perspective of gas analysis and reaction equilibrium.

Speaker: Haruka Sato (Tohoku University)

152 Optimization of Fe-Mn-Al-C low-density steels for forging application

pere.barriobero@upc.edu>; Towhid.Faraji@imf.tu-freiberg.de; Mathias.Zapf@imf.tu-freiberg.de; roberto.elvira@sidenor.com; irene.calliari@unipd.it; mirko.pigato@phd.unipd.it; ebasagana@comforsa.com; avilalta@comforsa.com; juan.emilio.rey@upc.edu; pcalopa@comforsa.com; Ulrich.Prahl@imf.tu-freiberg.de; jose.maria.cabrera@upc.edu; martino.oliboni@studenti.unipd.it, anna.mazzi@unipd.it

In the present paper the preliminary results of RFCS-funded LIGHTFORGE project, focused on the Fe-C-Mn-Al low-density steels, are discussed. The decarbonization of the automotive sector is a key goal to limit the greenhouse effect emissions and attain the Paris Agreement objectives and the reduction of energy consumption is together with improving safety standards paramount in modern transportation. To fulfil these objectives the development of strong, tough, and ductile steels for automotive applications is an essential part in steel research.. Low density Fe–Mn–Al–C steels steels may achieve a 15% diminution of steel density depending on the aluminum content and are promising candidates for structural forged parts owing to their capability to contribute in reducing the vehicle weight mainly achieved through alloying with aluminium (Al) (~1.3% density reduction per 1 wt.% Al). At the RFCS-funded LIGHTFORGE project, research has been focused on the design and selection of the Fe-C-Mn-Al low-density steels suitable for semi-industrial forging trials of massive components. The design of low-density steels was assisted by MatCalc and JMatPro software to select the chemical compositions of laboratory medium-scale ingots. Casting and hot forging/rolling processes were optimized by a sort of trial and error to overcome unexpected obstacles. The characterization of the microstructure by OM, SEM and synchrotron and the evaluation of its hot ductility allowed estimating the most important features to improve steel processability.

Speaker: Dr Mirko Pigato (University of Padova)

153 Investigation of the reoxidation behaviour of HBI samples produced on a laboratory scale

The increased production of direct reduced iron (DRI) in recent years, particularly in the form of metallised DRI pellets and hot briquetted iron (HBI), is a promising development in global ferrous metallurgy. One of the special features of these products is the fact that, unlike scrap, they do not contain any impurities that are harmful to the production of steel and can therefore be used in the production of high-quality steels. However, one of the negative characteristics of DRI is its relatively high reactivity, which means that handling, transporting and storing DRI require special consideration and analysis, as in this case a reduction in the degree of metallisation can be observed. This study is being carried out in cooperative collaboration with the aim of coordinating the development of some new equipment at ArcelorMittal/CRM, TU Bergakademie Freiberg and Montanuniversität Leoben (MUL) in order to map the entire process chain, which includes experiments on ore reduction, briquetting and reoxidation (ReOx) of HBI. Therefore, several climate boxes with different climatic conditions (higher temperature, humid and saturated atmosphere) have been designed at MUL to investigate the impact of climatic conditions on the ReOx of laboratory-scale produced HBI samples with different properties. The samples are weighed regularly during the storage period of 12 weeks in order to detect possible reoxidation by means of weight gain. In addition, the chemical composition, the degree of metallisation and the morphology of the samples are analysed before and after the tests. Hydrogen generation is also monitored with pH measurement and additional hydrogen detection sensors. The aim of this study is to understand and describe the fundamental mechanism of HBI reoxidation for the safety of future handling and transport logistics.

Speaker: Sergej Nesterov

154 Determining of iron oxide pellet porosity using image analysis

Hydrogen-based reduction of iron oxide is a promising new technology in fossil-free steelmaking. In the process, the iron oxide is usually fed in a form of spherical pellets or briquettes. In solid-gas -reactions, the porosity of the pellets is assumed to enhance the reduction kinetics via the increase of the available reaction surface area at the reaction interface. However, the multivariable and complex dynamics of the reduction system complicates the estimation of this effect, as it is known that the properties of the pellet evolve withing the progression of the reduction.
In the kinetic analysis procedure, determining the pellet porosity is a demanding task. Measuring the porosity of the pellets is conventionally based on tomography analyses. However, image analysis of SEM-images of pellet cross-section could provide more practical approach. In this study, a sophisticated image analysis procedure is developed to analyze the pellet porosity based on cross-section images. It was found that the porosity based on image analysis correlates reasonably well with the tomography analysis. In addition, the effect of cross-sectional porosity on the reduction rate of the pellets is analyzed by making use of numerical and statistical analysis.

Speaker: Mr Eduardo Borges Matos (University of Oulu)

155 Advanced fluid flow simulation for the RH process

In the RH process, the continuous circulation of liquid steel between the vacuum chamber and the ladle significantly affects decarburization and degassing rates as well as the productivity. Several CFD (Computational Fluid Dynamics) models have been developed to simulate the transient multiphase flow of melt and injected inert gas in RH plants in order to investigate the effect of different process parameters such as ladle size, snorkel length, immersion depth of snorkel, inert gas flow rate and number of tuyeres. The numerical results are compared with published analytical calculations and used to determine the homogenization time for different process parameters. The simulations show, among others, specific melt flow phenomena such as intensive surface fluctuations but also local dead water regions. These results can help to improve currently implemented RH degassing processes.

Speaker: Mr Hans-Jürgen Odenthal (SMS group)

156 Revolutionizing Blast Furnace Stockhouses: Reducing Degradation and Enhancing Performance

This paper presents a novel material handling scheme within a blast furnace stockhouse aimed at minimizing material degradation due to impact and friction in storage silos and weigh-hoppers. By reversing the conventional process—screening materials before storage rather than after—significant savings in equipment, layout footprint, maintenance, and dust collection capacity are achieved. Pilot plant tests support DEM calculations, demonstrating the feasibility of implementing concepts of this revolutionary solution in existing plants.
Caring for the material during its journey toward the blast furnace allows for an overall reduction in consumption. Charging material with lower fine content improves blast furnace performance.

Speaker: Mr Alessandro Siri (SMS group)

157 Local Area Production System

A central Manufacturing Execution System (MES) is a reliable and approved single-source-of-truth for production and material tracking. At the same time, a central system that integrates all automation systems and Enterprise Resource Planning can make it difficult to find slots for maintenance, updates or extensions. Its unavailability can be critical, potentially leading to a production stoppage. Additionally, integrating multiple heterogeneous systems adds a lot of complexity to the MES, increasing the need for frequent updates and maintenance. Local Area Production Systems (LAPS) improve flexibility and security while simplifying the MES without losing its benefits. LAPS integrates with a production area’s automation such as the warm area and handles production tracking. It receives production orders, materials and schedules from the central MES and reports the production results. LAPS allows line operators to manage production independently for a set period, using a backlog of schedules, materials and production orders. This ensures continuity even if the central MES or other tracking systems are impaired or offline. LAPS streamlines production by managing line sequencing, material tracking, test monitoring, and post production tasks like weighing, taking samples and inspection. Its integration with automation systems simplifies MES standardizations, making system upgrades easier. In the future, LAPS will connect on-premise systems to a SaaS MES. PSI will introduce LAPS as part of the PSI Service Platform, showcasing its benefits for production environment.

Speaker: Jan Thiel (PSI SE Process Industries and Metals)

158 AI-Based Optimization of Compressed Air Networks in Hard-to-Abate Industrial Sectors

Compressed air systems represent a critical utility in energy-intensive industries, particularly in hard-to-abate sectors such as steel, cement, and chemicals, where efficiency improvements can significantly reduce energy consumption and carbon emissions. This study presents an artificial intelligence (AI)-based methodology for the optimization of compressed air networks in industrial plants, leveraging advanced machine learning algorithms and data-driven models. The proposed solution employs AI algorithms for predictive maintenance, anomaly detection, and dynamic pressure control, enabling the system to autonomously adapt to varying production needs.
By analyzing historical operational data and real-time sensor information, the AI models identify inefficiencies, forecast demand patterns, and suggest optimal operating parameters. This intelligent decision-making process not only enhances overall system performance but also minimizes energy losses, reduces unplanned downtime, and extends equipment lifespan. The integration of AI-based control systems empowers end users with actionable insights and autonomous optimization capabilities, translating into tangible cost savings and operational resilience.
Case studies from the steel, cement and chemical industries demonstrate the effectiveness of the proposed approach, achieving up to 15% energy savings and a significant reduction in CO₂ emissions. The results highlight the transformative potential of AI as a key enabler for decarbonizing hard-to-abate sectors. This work underscores the strategic benefits of AI applications in compressed air systems and provides a scalable framework for future industrial implementations, supporting the broader goal of energy efficiency and sustainable industrial transformation.

Speaker: Lorenzo Orlietti (Alperia Green Future Srl)

159 Different Options of Stove Modernization using Innovative Top Combustion Stove of Kalugin Design

The global iron and steel industry is being impacted by a decline in steel demand and volatile situation in the global market of raw materials. Manufacturers are challenged to reduce the production cost of iron and steel by modernizing the existing production facilities in conditions of continuously growing requirements for provision of environmental measures. Iron and steel industry is considered as “dirty” production and many processes, including blast-furnace production, are sources of a big amount of combustion products and CO/NOx emissions. Many designs of hot stoves used for blast furnaces are not able to provide complete gas combustion during operation. On the contrary, top combustion stoves which have gained widespread use recently have proved its capability to remain environmentally “clean” during long-term operation. KALUGIN Company has developed and successfully implements top combustion hot blast stoves of its own design representing advanced and economically efficient technology meeting today’s high environmental requirements. Nowadays, modernization of existing stoves is being performed with different modernization options from replacement of existing burner design to full replacement of the stove. This paper gives a comprehensive assessment of various modernization options on the basis of such parameters as productivity, capital expenditures, project implementation period, reduction in CO and NOx emissions, which enables to choose the best option for modernization of existing facilities to improve productive efficiency and significantly reduce harmful emissions having adverse environmental impacts.

Speaker: Ms Marina Kalugina (KALUGIN JSC)

160 Oil Reconditioning in Metal Manufacturing

The metal manufacturing industry, vital yet environmentally taxing, heavily relies on oils for machining, lubrication, and corrosion resistance. This reliance, however, generates significant costs and environmental burdens, including disposal challenges, health hazards, and ecological damage. To address these concerns and foster sustainable practices, oil reconditioning techniques are gaining traction.
This paper reviews conventional and advanced oil reconditioning methods within the metal manufacturing sector. On-site reconditioning removes impurities, while re-refining processes restore used oil to base stock, creating a closed-loop recycling system. The study also examines environmentally friendly alternatives like vegetable oil-based cutting fluids and minimum quantity lubrication (MQL) techniques, which minimize conventional fluid consumption.
Oil reconditioning's applications span diverse metal manufacturing processes, including machining steel, aluminium, alloys, and titanium. Reconditioned oils function as cutting, hydraulic, and lubricating fluids, reducing virgin oil demand and waste. Integrating reconditioned oils with advanced cooling techniques, such as cryogenic cooling, dry cutting, and solid lubricants, further promotes sustainable machining.
Studies indicate a 70% reduction in emissions, waste, and energy consumption for steel and a 90% reduction for aluminium alloys through circular metallurgical practices. Oil reconditioning lowers machining costs and enhances occupational health by minimizing exposure to harmful mists and fumes. Vegetable oil-based cutting fluids demonstrate high corrosion inhibition efficiencies, sometimes reaching 100%.
This review highlights novel research opportunities in sustainable metallurgy, emphasizing the materials science of sustainable metals and alloys. Rethinking alloy design for enhanced recyclability and impurity tolerance is crucial. Scalability of reconditioning processes is essential to meet the demands of the 2 billion-ton annual metal production. By exploring these technical aspects, this paper aims to advance sustainable practices and reduce CO2 emissions in the metal manufacturing industry.

Speaker: Mr Anshuman Agrawal (Minimac Systems Pvt Ltd)

161 Green Manganese steel from remelting of hydrogen based Direct Reduced Iron (DRI) and green Ferroalloy: a CO2 free approach

Manganese is an important alloying element used in steel industry and is mostly used for increasing the strength without compromising the ductility. Currently, manganese is added as ferromanganese in steel to form manganese steel. Hence the final steel formation goes through series of steps after primary raw materials extraction, namely, ironmaking, crude steel production, ferromanganese production, steel refining and alloying to get the desired product. Carbon is used as the major reductant to produce iron and ferromanganese, which causes significant emission of CO2. To reduce this greenhouse gas emission, new innovative technology needs to be adopted using greener reductant as an alternative to carbon. In the present work, hydrogen for the reduction of Iron from iron ore pellets was used. The produced Direct Reduced Iron (DRI) was then flux-smelted in induction furnace with lime acting as a fluxing agent to obtain iron metal with low carbon. The obtained iron was then melted with green ferromanganese in certain proportions to obtain steels with composition close to the composition of Hadfield, Transformation Induced Plasticity Steel) (TRIP) and (Twinning-Induced Plasticity steel) TWIP steel. The results showed that the hardness of the produced steel was similar or better than the conventional steel and the proposed process emits no CO2.

Speaker: Pankaj Kumar (PhD candidate)

162 Next generation of sustainable HICON/H2® bell-type furnace systems

Bell-type furnaces are an integral part of cold rolling mills for carrying out the annealing process. The technology of high convection in a hydrogen atmosphere (HICON/H2®) was introduced to the market as early as 1972. Continuous further developments have increased performance, quality, efficiency and reduced costs.

This next generation of sustainable bell-type furnace systems, called GREENBAFx®, has an innovative system for heating energy into the process (direct heating) and returning the energy released during cooling (heat exchange).
In the new system, the heating energy is introduced directly into the process gas. For this purpose, an electrical heating system is arranged inside the annealing base.
The impeller is designed so that it flows through the heater without flow losses.
To prevent lubricant residues from adhering to the electrical heating elements, a special temperature/atmosphere program cleans the heating elements before each annealing process.

The heating hood, cooling hood and protective hood are replaced by a process hood. Cooling is provided by a cooler integrated into the annealing base.
There is no need to change heating bell and cooling bell. Fewer handling and operating costs represent a significant operational and logistical simplification.
Furthermore, less space is required than with conventional systems.
The system is highly efficient and emission-free thanks to the reduction in heat loss. CO2 and NOx emissions are completely avoided.
It is also possible to configure a hybrid-heated system. This is additionally equipped with a heating hood and can now be operated either with the integrated electric direct heating and/or with a gas-fired heating hood (natural gas, hydrogen).
This offers the advantage of being able to flexibly select the type of heating depending on the current media availability or costs.
Retrofitting in existing systems is possible.
Compared to a classic, gas-fired system, enormous amounts of CO2 and NOx can be saved.

Speaker: PETER SEEMANN (Ebner Group)

163 How Biochar Drives the Transition to Sustainable Steel Production

Steel is a fundamental material in modern infrastructure, transportation, and industrial applications, valued for its strength, durability, and recyclability. However, conventional steel production remains a major source of CO₂ emissions due to the reliance on fossil-based coke as both a reducing agent and an energy source. To align with global climate objectives, the steel industry must transition towards environmentally sustainable and carbon-neutral manufacturing processes. The utilization of biochar instead of fossil coke in steel production represents an innovative and sustainable solution to this challenge.
Produced in SYNCRAFT’s Reversepowerplants, biochar is derived from climate-neutral forest residues. In Reversepowerplants, forest residues are processed in a resource-efficient and sustainable way to generate bioenergy in the form of electricity, heat and gas. As an additional product, the plants produce biochar, which has the capacity to store 30% of the CO₂, which is originally stored in the tree (which, if rotted, would be released back into the atmosphere).
In traditional blast furnace processes, biochar can replace fossil coke as a reducing agent, leading to a substantial decrease in CO₂ emissions. Additionally, in the Pulverized Coal Injection (PCI) process, biochar can substitute coke as a fuel, ensuring the necessary high temperatures for iron ore reduction while lowering the carbon footprint. Furthermore, biochar can support innovative direct reduction methods, in which iron ore is processed using natural gas or green hydrogen, further enhancing the environmental sustainability of steel manufacturing.
SYNCRAFT’s biochar exhibits high homogeneity and a fixed carbon content comparable to anthracite, making it particularly suited for steel applications. By integrating biochar into the steel production process, the industry can significantly reduce its environmental impact while maintaining operational efficiency and material performance. The adoption of biochar as a carbon-neutral and non-fossil alternative marks a crucial step toward a more sustainable and environmentally responsible steel industry.

Speaker: Mr Marcel Huber (Syncraft GmbH)

164 Effect of gas volume expansion on carbothermic reaction of phosphoric acid to produce white phosphorus

White phosphorus is one of element listed by European Union (EU) as strategic substance that facing supply crisis. Therefore, method to recover phosphorus from various resources such as steel slag, sewage sludge, and semiconductor waste is urgently needed for a stable white-phosphorus supply.
We propose a novel approach for white phosphorus production through the carbothermic reduction of waste phosphoric acid. To implement and optimize production process, the mechanism of reduction needs to elucidate because this reduction is special, where high volumes of gases are generate (1 mole H3PO4 to 16 moles CO, 6 moles H2, and 1 mole P4) For that purpose, we conducted experiment using two types of carbon material, activated carbon (AC) and metallurgical cokes (MC), where AC have two order larger surface area compare to MC. However, despite the two order larger surface area, the reduction degree of MC is comparable to AC. It is concluded that reaction in the pores is not dominant and mainly occurred at the external surface (packed bed surface area).
To understand the H3PO4 carbothermic reduction mechanism in the packed bed, the reaction model considering the gas volume expansion in the packed bed (as the function of the packed-bed height), was developed. The proposed reaction model, reasonably agree with the experimental values, indicating the validity. In the case of AC, the carbon at the top of the packed bed is rapidly consumed during the carbothermal reduction of H3PO4 and that the packed-bed height decreases rapidly, compared to MC. Therefore, for stable, industrial-scale white-phosphorus production, an adequate supply of carbon material to replenish the depleting material is necessary.

Speaker: Andrey Stephan Siahaan (New Industry Creation Hatchery Center, Tohoku University, Japan)

165 Thermal simulation of WAAM process to support production

Wire Arc Additive Manufacturing (WAAM) is an additive manufacturing (AM) production process used to 3D print large metallic parts. This new process combines Gas Metal Arc Welding (GMAW) equipment with a robotic arm integrated with a welding power source. The part is printed with WAAM layer after layer each composed of successive weld beads. Benefits of WAAM compared to more standard processes includes the versatility of the process to design product families, reduction of lead-time to deliver final parts, reduction of weight, costs and carbon footprint of the manufactured products.
Nevertheless, production with WAAM requires to define accurately all process and production parameters to deliver product of high quality. Hence, simulation of WAAM process can play an important role to shorten and ease the process of qualification. Moreover, simulation can also be an important tool to support production of parts made with WAAM.

Many numerical models have been presented in the literature in order to describe Additive Manufacturing at the scale of the molten pool, to understand how defects can be generated, how process parameters impact material properties… Yet, only a few numerical models allow to describe the process at the scale of the whole part. The proposed work consists in developing a simplified thermal model of the WAAM process, able to evaluate inter-layer cooling time and the thermal history at any point of the manufactured component. The simulation has been implemented using the finite element software Code_Aster. It has been calibrated and validated thanks to experimental data.
The numerical tool developed helps the industrialization of WAAM at 3 different levels:
• Extrapolation of process parameters to new dimensions of a product family
• Determination of cooling time and production of a part in a given material
• Optimization of the batch sizes to maximize the productivity of the robot.

Speaker: Mériane Fernandes

166 Development of a 1D Numeric model for axial pebble bed Thermal Energy Storage (TES) as a design decision tool for waste heat recovery in steel plants

Heat recovery from waste gas in heavy industries, such as steel plants, is crucial for enhancing energy efficiency and sustainability. This process captures thermal energy released during production and repurposes it for other applications within the plant. This approach not only reduces operational costs but also minimizes energy wastage and lowers greenhouse gas emissions, supporting global efforts to combat climate change. Integrating heat recovery technologies thus represents a significant step towards more eco-friendly and cost-effective industrial operations. One of the key challenges in implementing such energy efficiency solutions lies in designing the core reactor/devices and auxiliary systems to ensure optimal integration and achieve the expected benefits.
This work highlights the numerical modeling of heat transfer and hydrodynamics within an axial pebble bed thermal energy storage (TES) system as a preliminary tool for testing use cases and optimizing design decisions for waste heat recovery in steel plants. It includes the validation of the developed model with experimental data from both experiments and literature sources. A sensitivity analysis using the model reveals the importance of optimizing the specific heat capacity of the solid particles, the height of the pebble heater, and the charging time to maximize energy extraction from the waste heat source. The diameter of the solid particles also impacts the effective thermal conductivity of the TES, due to its direct proportionality to the radiative contribution of the thermal conductivity, while also influencing the pressure drops across the system.

Speaker: antoine moussalem

167 Advancing Hydrogen Plasma Smelting Reduction: Process Simulation and technical and environmental assessment

The steel industry is responsible for 7% of global CO₂ emissions, with the blast furnace–basic oxygen furnace (BF-BOF) process accounting for approximately 70% of the total emissions from steel production. Given the significant environmental impact, the European Union has set a target to achieve net-zero CO₂ emissions by 2050. Reducing carbon carriers, mainly in the form of coke consumption is essential to reaching this goal. As an initial step, natural gas has been introduced in the direct reduction routes (DR) as a substitute, significantly lowering carbon emissions. However, this approach alone remains insufficient, as the reduction process still relies on carbon, resulting in CO₂ and CO as byproducts. A promising alternative is the use of ionized hydrogen as a reducing agent in the Hydrogen Plasma Smelting Reduction (HPSR) method where the primary byproduct of the reduction process is water vapor (H₂O). In this process, a mixture of hydrogen and argon is introduced into the DC electric smelter through a hollow electrode. HPSR utilizes fine iron ore as input, eliminating the need for conventional BF-BOF agglomeration processes. The pilot plant can process up to 200 kg of iron ore per hour and currently operates in batch mode, with efforts underway to develop a continuous process. In this work, a flowchart-based HSC simulation of the HPSR pilot plant is developed, aligning with experimental data from the current setup. To enhance efficiency, the system is further optimized by incorporating a preheating cyclone that recirculates HPSR off-gas and reduces electricity consumption. A technical and environmental analysis is conducted to compare the HPSR process with conventional steelmaking processes, such as the BF-BOF route and direct reduction with an accompanying electric arc furnace smelting step. The analysis evaluates differences in CO₂ emissions and electricity consumption, with the total power demand remaining comparable to the conventional routes.

Speaker: Hamideh Hassanpour (postdoc)

168 FUME TREATMENT PLANT FOR A STEELMAKING FACILITY: OVERVIEW OF THE MAIN FACTORS THAT AFFECT THE FINAL CHOICE

The Fume Treatment Plant sizing needs to be highly customized. The steelmaking equipment characteristics and arrangement, the general site layout, the environmental local regulations and the best available technologies (BAT) for the pollution control have to be taken into account. The final choice implies always the comparison among different solutions regarding the fume capturing, the cooling equipment, the pollutants abatement devices, the possible energy recovery and so on. The choices for FTP are also linked to the choices of the Water Treatment Plant.
An overview with advantages and disadvantages are presented, considering the data coming from real experiences.

Speaker: MATTEO TOMBA (PERT SRL)

169 Fast and robust order-based scheduling to solve the Mid-Term planning problem

Major focus for order-based scheduling is the determination of valid production sequences considering any plant constraint on the one hand while minimizing the amount of required setup coils on the other hand. A mid-term solver for one production step should automatically select orders from a given set of available orders (order backlog), assign them to a certain plant and define valid production sequences. To be able to integrate as many different constraints as possible a solver should be able to consider local (order-to-order) as well as global constraints (based on the full order sequence). We present the DynReAct mid-term planning module exploiting Tabu-Search combined with a Traveling-Salesman Solver.

Speaker: Jens Brandenburger (VDEH-Betriebsforschungsinstitut)

170 Smarter Galvanizing through Zinc Coating Optimization with EMG iCASS®: A Modular AI-Driven Platform

In hot-dip galvanizing processes, achieving optimal zinc coating thickness while minimizing material consumption remains a significant challenge. Traditional control methods often rely on reactive adjustments based on delayed coating thickness measurements, leading to inefficiencies and increased zinc consumption especially at strip transitions with material and coating target changes. To overcome these limitations, EMG iCASS® (intelligent Control and Analytical Software Solutions) provides a modular, AI-powered platform for real-time process optimization in continuous galvanizing lines (CGLs).

By integrating machine learning models, predictive analytics and real-time control mechanisms, EMG iCASS® dynamically optimizes process parameters based on both historical and live production data. The platform allows the implementation of individual modules or a complete control solution.

One of the core outcomes of this approach is the virtual hot measurement module, which enables immediate predictions of zinc layer thickness right after material and coating target changes, reducing the dependency on conventional hot measurement techniques and too late cold measurement results.

Additionally, the safety margin optimization module statically or dynamically adjusts the target zinc thickness to prevent undercoating while minimizing excess consumption, leading to additional material savings.

The complete real-time air knife control module refines the coating process by adjusting pressure or geometric settings based on predictive models, ensuring precise and uniform zinc application. In addition, the nozzle position optimisation module - applicable to CGLs with an existing EMG eMASS® strip stabilization system - eliminates misalignment between the strip and nozzle lips, preventing a wedge-shaped coating profile.

Industrial trials have demonstrated that EMG iCASS® not only enhances process efficiency but may also significantly reduce waste and improve product consistency. By leveraging real-time ML-based predictions, the system ensures a precise and adaptive control mechanism. The platform approach makes it highly flexible and adaptable to various CGL settings, positioning it as a future-proof solution for data-driven process optimization.

Speaker: Mark Kreso

171 Towards zero-defect manufacturing for flat steel production - Introduction of the SurfConInspect Project

Resource-efficiency and competitiveness are main aims of the European Green Deal transformation. In this global restructuring process yield improvement and reduction of waste aimed by a zero-defect production are low-cost opportunities for European steel manufacturers to realize a more sustainable production.
Enabling zero-defect manufacturing for flat steel production requires an early detection of surface defects and a fast and adequate control action once a defect appears. Therefore, the SurfConInspect (SCI) project follows a holistic approach incorporating new concepts for the measuring of surface defects as well as for the support of adequate control actions.
For the support of adequate control actions, a modular SCI framework will be implemented able to provide in-coil control actions for the operator as well as directly for the process control systems. To support the operator the applicability of Augmented Reality (AR) devices for the online visualization of quality information directly on the moving coil will be investigated and a prototypical implementation is foreseen at an Inspection line of a tinplate production plant.

Speaker: Jens Brandenburger (VDEH-Betriebsforschungsinstitut)

172 Mitigating Worker Skills Gaps using Digital Workflows & Mixed Reality

The average plant worker’s age is increasing while headcount is leaner providing fewer opportunities to transfer knowledge from more to less experienced people. Workflow art, the correct methods to execute tasks, is being lost with retirees and leaner workforces while skill gaps and productivity pressures are increasing. The collection of these workflow arts is sometimes summarized into the term “tribal knowledge”. Each day 10,000 skilled workers retire in the USA alone. Unless that knowledge is captured it leaves with them. The European workforce statistics are more worrisome. Workforce demographic shifts of retirees, generational preferences, and other factors including pandemic have accentuated the urgency to bridge the gaps and mitigate loss of tribal knowledge. State-of-art digital workflow systems enable efficient and flexible multi-media capture of tribal knowledge. This presentation will provide a background of digital workflow technology before providing examples of how one system has been used within the metals industry to digitally collect, preserve, and share tribal knowledge. Best practices of how to successfully implement Industry 4.0 technologies will also be discussed.

Speaker: Mr Eric Almquist (StarTool)

173 Safer Electric Melting: How robotics is transforming the EAF steel production

This paper presents a novel robotic approach to enhancing safety and efficiency in steel plant operations, focusing on steel sampling, deslagging, inspection, and automatic ignition systems for Electric Arc Furnaces (EAFs). Designed for harsh industrial environments, these smart robotic solutions significantly reduce human exposure, improve operational accuracy, and increase productivity.

Equipped with multi-tool capabilities, high-speed precision robots offer flexibility for both greenfield and brownfield installations, ensuring seamless integration into existing workflows. The inclusion of an automatic ignition system further enhances process efficiency by enabling precise, reliable ignition without manual intervention.

These customized robotic systems support the digital transformation of steel production, aligning with Industry 4.0 principles. By shifting operational roles from manual execution to supervisory control, they contribute to a safer, more efficient, and highly competitive steelmaking process.

Speaker: ION RUSU (POLYTEC SPA)

174 Integrating CO₂ Reporting with Physically Consistent Material and Energy Flow Analysis to Improve Circularity of Steel Products

Improving the circularity of steel products requires reliable tools for ECO design that integrate key environmental properties, such as CO₂ footprint and embodied energy. These data are typically de-rived from environmental reporting and Life Cycle Assessment (LCA) analyses. However, ensuring physically consistent and traceable information - grounded in fundamental principles such as mass and energy conservation - is essential for accurately assessing complex process flows and supporting reliable sustainability decisions.

This work introduces a novel approach that ensures physically consistent modeling of material and energy flows while integrating CO₂ accounting. A new graphical notation for substance and energy flow modeling has been developed, designed to handle both known and uncertain data. This notation enables serialization into a structured JSON format, providing a standardized and flexible data repre-sentation. By translating this representation into a mathematical model, optimization-based data rec-onciliation ensures consistency, even when faced with contradictory or incomplete input values.

The newly developed software application includes a graphical user interface combined with a mathe-matical solver. It is presented with the example of an Electric Arc Furnace (EAF) steelworks case study. This example showcases how ECO-relevant flows can be modelled - including raw material inputs, energy consumption, emissions, and byproducts - while maintaining physical consistency. The system is designed to be compliant with ESRS reporting, enhance ECO reporting and support deci-sion-making to improve resource efficiency and reduce environmental impact. In addition to process modeling, the system incorporates materials selection based on ECO properties derived from ESRS data, enabling informed decisions on resource efficiency and sustainability.

This presentation underscores the significance of physically consistent modeling for sustainable process design. It highlights the practical advantages of this approach embedded into a scalable and transparent framework, providing actionable insights for industries striving to meet stringent environmental standards while advancing circularity and innovation in steel production.

Speaker: Dr Uwe Diekmann (Matplus GmbH)

175 PREVENT BOTTLENECKS AND OPTIMIZE LADLE AND CRANE LOGISTICS FOR AN EAF-BOF MELT SHOP

In the transition to green steelmaking, hybrid steel plants incorporating both EAF and BOF technologies face several critical logistical challenges. Different tap-to-tap times, variations in steel chemistries and temperatures, the positioning of new equipment, and integration with existing plant infrastructure significantly impact ladle logistics. Inefficient ladle flow and overutilized cranes can cause delays at both the BOF/EAF and casters, but these issues can be mitigated. In this paper, we present the main challenges and solutions based on simulation work with six European integrated steel plants undergoing this transformation.

Speaker: Paul Uhl-Hädicke

176 FROM DATA TO DECISION: UNIFYING PRODUCTION MANAGEMENT AND TPQC FOR OPTIMIZED STEEL PRODUCTION

In today’s steel production operations, seamless integration of the individual production
steps, besides the optimization of the individual production units, is key to achieving
operational excellence. While Production Management (MES) drives production efficiency
by orchestrating plant-floor operations from customer order entry to shipment of the final
product, Through-Process Quality Control (TPQC) ensures that the final product meets
stringent industry and customer requirements. Integrating real-time quality information and
even quality-based decision of TPQC into the Production Management is the logical next
step to automatically organize steel production in a coordinated manner.
This paper proposes a holistic blueprint to integrate Production Management and TPQC.
By tying together real-time process data from Production Management with data-based
decision-making at quality checkpoints in TPQC, steel manufacturers can proactively
respond to deviations, prevent costly rework, and improve first time right rates. When an
out-of-specification process occurs, this integration allows immediate feedback loops,
supporting efficient quality management. Additionally, smart intra-logistics integration
within Production Management reduces unnecessary transport of products thereby
increasing efficiency, streamlining logistics, and shortening overall production time.
By implementing these strategies, steel manufacturers can transition towards a truly
integrated production management, logistics and quality control ecosystem, ensuring right
quality products, optimized operations, and increased operational excellence.
This paper will elaborate on this integrated approach of production management and give
examples of implemented use-cases.

Speaker: Mr Kurt Herzog

177 Machine learning model for mould powder consumption in continuous steel casting

Mould powders play a critical role in the continuous casting of steel by facilitating lubrication, regulating heat transfer, absorbing deoxidation products, preventing reoxidation, and providing thermal insulation at the meniscus. Accurately predicting mould powder consumption is essential for optimizing efficiency and cost-effectiveness in steel manufacturing. However, existing models lack consensus on the key influencing factors, beyond slag viscosity and casting speed, which govern casting powder consumption in continuous casting of steel.
This study aims to develop a machine learning model or equation to predict mould powder consumption and identify the most significant influencing factors. This initiative seeks to achieve enhanced process optimization in the steel manufacturing by capitalizing on data-driven insights. In addition, existing mould powder consumption models from the literature are tested using industrial data. The dataset was sourced from internal measurements at voestalpine Stahl Linz, with average values calculated for each slab, and was further enhanced with calculated parameters from the literature, such as surface-to-volume ratio. A rigorous preprocessing pipeline including data cleaning, outlier removal, and feature selection based on statistical relevance was applied to ensure model reliability. A Random Forest Regressor was trained and evaluated using cross-validation.
The model achieved strong predictive performance, with an average R² score of 0.88, indicating high accuracy. Feature importance analysis revealed that steel carbon content had the greatest impact on mould powder consumption, followed by casting speed, surface-to-volume ratio, steel titanium content, and slag viscosity. These findings highlight the critical role of steel composition and operational parameters in determining mould powder usage. The developed machine learning model provides a reliable tool for predicting mould powder consumption trends, enabling improved decision-making and process control. By merging industrial data with advanced analytics, this study contributes to improve the efficiency and cost-effectiveness of steel casting operations.

Speaker: Pedro Paulo da Silva Cruz (K1-MET)

178 PERT BS STAND APPLICATION IN A UPGRADE OF SECTION MILL – CASE HISTORY-

Today’s long steel products market with ever smaller profit margins and stronger competition requires the use of rolling mills with minimized operational cost and the capability of assuring a final product of very high quality. Starting from these considerations, a PERT customer in Turkey decide to use the PERT BS (bi-Support Stands) in order to upgrade the existing section mill.
The new stands was installed starting from the roughing area up to the finishing area. In the finishing area a particular tailor made solution was developed for the production of flat bars in order to perform the edging passes without the use of traditional convertible stands in order to reuse as much was possible the existing equipment and avoid new civil works and long stops in production for the upgrade of the line.
The described case history, will show at the audience all the project developments starting from the preliminary customer request (increase in production quality, reuse existing electrical motors, short installation time, fast installation for the new stands, reduced investment cost...etc) up to the production restart.

Speaker: Mr NICOLA TOMBA (PERT SRL)

179 Advancements in Genius CM® Chatter: Enhancing Chatter root cause detection and vibration management at BRS PLTCM

Chatter remains a critical challenge in cold rolling mills, as different vibration types can lead to severe strip defects or mechanical failures. This paper demonstrates the advancements in the Genius CM® system, based on its application at the Big River Steel (BRS) Pickling Line Tandem Cold Mill (PLTCM), in the context of enhanced Chatter root cause detection and vibration management.

Genius CM® is a condition monitoring system designed to solve vibration issues like those that occurred at BRS PLTCM after several years of operation. The system was implemented in stages, beginning with comprehensive data collection and the implementation of an Automatic Slow Down feature to manage acute vibration events. Based on the ongoing cooperation between SMS and BRS and based on the analysis results, new advanced functionalities were developed.

A first new functionality provides the option to control the attachment of the backup roll pusher cylinders, based on vibration conditions, directly from the Genius CM® system. Further advancements include the automatic detection of Chatter root causes. Enhanced reports and new views help to identify mechanical issues causing Chatter. At BRS PLTCM, backup roll bearing damages were clearly identified and the results were verified by inspections. Consequently, targeted maintenance actions were executed. These new capabilities make the Genius CM® system an indispensable tool for mill operation in the context of proactive vibration management to maintain optimal mill performance. As an outlook, the paper discusses the option and potential for implementing vibration-based speed recommendations in order to avoid Chatter issues and optimize the mill’s productivity.

In summary, the deployment and continuous development of the Genius CM® system at BRS PLTCM highlight its important role in handling complex vibration challenges. These advancements will not only improve current operations but will also be the basis for future innovations and (process) optimizations.

Speaker: Sebastian Richard (SMS group)

180 Improvement of Breakout Prevention for startup stability enhancement in high productivity thin slab casters

The continuous casting process is crucial in metallurgy, yet its startup phase is often plagued by significant fluctuations and instabilities, complicating the reliable prediction of potential breakouts. Traditional breakout detection systems are typically activated only after steady-state conditions are achieved, which means they engage only after a considerable length of material has been cast.

Addressing this challenge, the SMS group introduces an enhancement to its HD mold system, renowned for ensuring product quality. This innovative extension reliably detects sticking breakouts during the critical startup phase. By providing real-time monitoring and control from the onset of casting, this system significantly enhances safety and operational efficiency, setting a new standard in continuous casting technology.

Speaker: Dr Thomas Pursche (SMS group)

Estad2025_COPYRIGHT_ASSIGNMENT_STATEMENT.pdf

181 Experiences and lessons learned from Metso’s Outotec pilot DRI smelting tests

“A smelting furnace (SAF, OBSF, ESF) has been recognized as an important new process step in decarbonization of iron and steel production. For de-risking the industrial projects utilizing new technologies, various test work steps have been necessary for scale up purposes. This paper is presenting Metso experiences and lessons learned from the in-house smelting test work. The most interesting topic are experiences of the new 3-in-line pilot DRI smelting furnace, where smelting of tens of tons carbon containing DRI and carbon free containing DRI has been done in Q1-Q2 2025.”

Speaker: Timo Haimi (Mr.)

182 Novel production route of fully processed high-Si NGO steels for e-mobility at Marcegaglia Ravenna plant

At Marcegaglia Ravenna plant has been implemented a novel production route, patent pending, of fully processed Fe-Si grades focused on industrial and e-mobility applications. In this study are reported the main metallurgical levers of the adopted production cycle and their effectiveness on the magnetic properties in terms of low loss, high permeability and absence of aging.

Speaker: Dr Francesco Barberini (University of Bologna)

Wednesday 8 October

183 Plenary lecture

08:50 Time to change rooms

Alloy Design & Microstructure Control

4.1.1

Convener: Dr Ettore Anelli (Franchini Acciai SpA)

184 Boron alloyed free cutting steel: a new candidate for Pb steel substitution

Boron in steel might form boron nitrides and/or boron oxides. Hexagonal boron nitride is a solid lubricant and as a second phase in steel it improves machinability (tool lifetimes as well as chip breaking). In addition, boron in oxides lowers the melting point (or glass transition temperature). B2O3 is known as a low melting phase with similar properties than Pb inclusions. Unfortunately, the formation of a significant amount of B2O3 in steel is difficult and expensive. The present investigation shows that under regular industrial conditions and with moderate boron additions a well-designed balance between nitride and oxide formation leads to optimum machinability behavior. Longitudinal turning and grooving tests of this new boron steel result in longer tool lifetimes in comparison with leaded steels. The optimum operation zone in drilling is comparable with the Pb alloyed steel. Chip breakage diagrams were evaluated. The chip breakage behavior is better than that of standard steel without Pb but is not quite as good as that of Pb-alloyed steels.

Speakers: Dr Hans Roelofs (Steeltec AG), Paulina Unifantowicz (Steeltec AG)

185 Effect of carbon content (0.61 to 0.99 wt.%) on bainite transformation kinetics, structure and tempering resistance in low alloy steel

The bainite microstructure, transformation kinetics and tempering resistance have been studied as a function of carbon content from 0.61 to 0.99 wt. % in low alloy steels. The carbon content strongly affects the bainitic transformation kinetics and hardness which are both increased by increasing carbon content. The tempering resistance also varies depending on carbon content and a higher carbon content with an initially higher hardness also gives slightly improved tempering resistance for short tempering times. The main reason for the decrease in hardness during tempering is related to the decrease in dislocation density for all four steels investigated. The higher tempering resistance for higher carbon content steels appears to be partly related to a lower change of dislocation density during tempering.

Speaker: Adam Ståhlkrantz (Swerim AB)

186 Microstructural optimization and mechanical behavior of SS-QP treated 30CrNiMo8 steel

The quenching and partitioning (QP) process aims to achieve superior mechanical properties and enhanced toughness by developing a microstructure consisting of martensite and retained austenite. In this study, single-step (SS) QP treatments were applied to the commercial 30CrNiMo8 steel, a material widely used in industrial high-strength applications but not specifically engineered for this process. Preliminary studies on the initial microstructure are performed through the application of different austenitization parameters. Microstructure evolution was examined using XRD and SEM/EBSD, while tensile tests were conducted to evaluate the impact of the treatment on the final properties of the material. SS-QP treatments were successfully implemented, delivering high tensile strength and improved ductility. Strain hardening behavior was analyzed and compared with specimens treated using conventional quenching and tempering treatments. The results demonstrate the feasibility of applying the QP process to 30CrNiMo8 steel and highlight the importance of initial microstructural control and treatment design in achieving desired mechanical performance.

Speaker: Marco Belfi (Politecnico di Milano)

187 Role of Vanadium in welding of flat products in High-Strength Low-Alloy Steel: microstructure and mechanical properties

High-Strength Low-Alloy (HSLA) steels are widely used in structural applications, requiring a thorough microstructural analysis to optimize the strength and toughness of welded joints. During multi-pass welding, thermal cycling leads to the formation of a complex Heat-Affected Zone (HAZ), consisting of sub-regions with diverse microstructural constituents, including brittle phases that influence the static and cyclic mechanical resistance of HSLA steel joints. This study evaluates the effect of Vanadium (V) addition on the HAZ microstructure in 15 mm thick S355 steel welds produced by robotic GMAW welding. A steel variant micro-alloyed with both V and Niobium (Nb) was also considered. The results are compared to a standard C-Mn S355 steel without micro-alloying elements to assess the impact of V and Nb on weld microstructure and mechanical performance. The results reveal a heterogeneous microstructure with ferrite of several morphologies, bainite, and martensite/austenite (M/A) islands. The presence of vanadium reduces the solubility of carbon during phase transformations, favoring the formation of ultrafine precipitates (~11 nm) and reducing the M/A phase in the high vanadium (0.1 wt%) variant compared to the vanadium-free material. Nevertheless, the micro-alloyed variants improve mechanical strength (yield and ultimate strength) without loss of ductility or fatigue resistance. The combined presence of both hard and soft microstructural constituents in HAZ allows a stress-damping behavior, which, together with the presence of very fine precipitates, promises improved resistance to crack propagation under different loading conditions.

Speaker: Andrea Di Schino (University of Perugia)

188 Designing thermomechanical processing schedules for Mo- and Cu-containing quenching and partitioning medium-Mn steels for multiphase forgings

One of the most promising groups of steels for future forging applications are medium-manganese (medium-Mn) steels, which develop finely dispersed retained austenite (RA) during the quenching and partitioning (Q&P) heat treatment process.
RA between the martensitic laths significantly improves ductility and fracture resistance by impeding the propagation of microcracks through transformation-induced martensite formation.
Another challenge in the steel industry is the increasing presence of residual elements in recycled steel scrap, such as copper. As the concentration of copper in "green" steel is expected to rise in the future, understanding its impact on the thermal characteristics of steel is crucial.
In this study, three medium-Mn steels with a basic composition of 0.17%C-4%Mn-0.8%Al-0.5%Si, alloyed with molybdenum and copper, were subjected to Q&P heat treatment. The research involved a dilatometric study, initially focusing on the basic thermal analysis of the tested alloys, followed by the application of a wide range of temperature-time conditions representing the Q&P process. Both deformed and undeformed samples were analyzed to evaluate the impact of hot deformation on phase transformation kinetics. Subsequently, the steels underwent an integrated thermomechanical processing (simulating forging) and Q&P heat treatment using the Gleeble 3800 simulator, closely replicating industrial manufacturing conditions.
Following physical simulations in the dilatometer and Gleeble system, microstructural characterization was conducted using light microscopy and scanning electron microscopy (SEM). The fraction of RA was quantified through X-ray diffraction analysis. The results indicated that even small additions of alloying elements, such as 0.3% Mo and 1% Cu, influence critical temperatures and phase transformation kinetics, highlighting the necessity of tailoring heat treatment parameters to the specific chemical composition of the steel.

Acknowledgements
The study was funded by National Science Centre, Poland under the OPUS call in the Weave programme, grant no. 2021/43/I/ST5/02658 and by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – 504849602.

Speaker: Mr Adam Skowronek (Silesian University of Technology)

Blast Furnace Process Optimization & Control

1.3.1

Convener: Prof. Davide Mombelli (Politecnico di Milano - Dipartimento di Meccanica)

189 Solid as Iron: Integrated Blast Furnace Control, Optimization, Condition Monitoring, and Simulation

Efficient blast furnace operation is essential for competitive iron and steel production, impacting productivity, hot metal quality, and cost-effectiveness. This paper explores how a combination of integrated automation systems enabled the successful start-up and stable operation of a blast furnace following a relining that included the installation of a bell-less top charging system:
A flexible, state-of-the-art process control system acts as the plant’s digital heart. It is supported by a comprehensive digital knowledge package, which includes operational knowledge from a rule-based expert system, maintenance knowledge from a predictive condition monitoring system, and a test and training system to enhance the operations team’s expertise.

Speaker: Dieter Bettinger (Primetals Technologies)

190 A blast furnace tapping simulator to better understand dead man flotation scenarios

In the present study we implemented a simplified but fast simulation tool to keep track of the liquid fill levels of pig iron and slag inside a blast furnace (BF). It is able to calculate the estimated tapping rates based on only a few mandatory input parameters like the production rate obtained from the currently active charging recipe and the tuyere and topgas pressure levels. The calculation method is based on two main models: (i) in the hearth of the BF we only account for the vertical force balance of burden load, gas pressure and buoyancy of the dead man. From this force balance we can estimate the flotation behavior of the dead man and the hydrostatic pressure at the entrance of the taphole. This pressure level is used to solve (ii) the momentum balance for iron and slag inside the taphole to calculate the tapping flow rate for both phases. The taphole model is currently based on a stratified fluid assumption and also accounts for taphole erosion during the tapping process. The BF hearth is discretized in radial and angular coordinates. Hence, it is possible to account for heterogeneous porosity of the dead man and investigate various flotation scenarios. The simulation tool is therefore an efficient way to study and better understand BF tapping behavior in comparison with other available data like temperature measurements of the hearth. Further enhancements of the tool will include a more detailed taphole model that will account for conditions where the stratified fluid assumption might not be correct.

Speaker: Stefan Puttinger (Johannes Kepler University Linz)

191 Burden distribution modeling to diagnose blast furnace operations

This paper presents the Hatch burden distribution model and use cases where the model has been able show blast furnace operators how changes in the burden distribution pattern can help their blast furnace operation. Two cases will be presented, the first to show how the model helps to visualize the impact of the bell less top chute wear on the burden distribution profile. The second to show how the model can be used to illustrate burden distribution profile changes within the blast furnace when charging coke from the center to the wall.

Speaker: Sa Ge (Hatch Ltd.)

Cooling & Solidification Control

2.3.3

Convener: Marco Alloni (Prosimet S.p.A.)

192 Hybrid solution for local heat transfer coefficients in a transient solidification model for continuous casting

Abstract

The heat transfer coefficient (HTC) is an essential parameter in the numerical simulation of solidification during the secondary cooling zone in continuous casting. Accurate prediction of the HTC is essential for controlled slab cooling and ensuring product quality by preventing crack formation. The HTC is commonly estimated using empirical equations from literature. However, an alternative approach is statistical regression modeling based on experimental data. This study presents the development and evaluation of regression models trained on measured data from the Nozzle Measuring Stand (NMS) at Montanuniversität Leoben. Multiple regression techniques were implemented using Python, and their performance was evaluated using the error values RMSE (root mean square error) and MAE (mean absolute error).

At the Chair of Ferrous Metallurgy, an offline numerical simulation software, m²CAST, has been developed to integrate experimental HTC and water distribution (WD) data into predictive modeling. The software enables solidification simulations by incorporating regression-based HTC predictions as boundary conditions. Various regression models were implemented using Python and compared to optimize HTC predictions. The impact of higher HTC values on the precision of the model was investigated. Additionally, feature importance analysis, using the Pearson Correlation Matrix and feature selection methods, identified the most influential parameters for HTC prediction.

Simulation outcomes from the offline simulation software m²CAST were used to validate the impact of operating parameters and variations on solidification profiles. The dependency of HTC on nozzle type, spray water distribution, and initial slab temperature was analyzed, revealing critical secondary cooling optimization. This study demonstrates the potential of machine learning-driven HTC modeling to enhance solidification simulations for industrial applications, improving process control and product quality in continuous casting.

Keywords

Continuous Casting, Secondary Cooling, Heat Transfer Coefficient, Simulation, Regression Model

Speaker: Ms Monika Seidl (K1-MET GmbH and Montanuniversitaet Leoben)

193 Simulation of transient temperature and solidification evolution in a continuously cast slab using multiple transverse sections

Accurate prediction of the temperature distribution in continuously cast steel slabs is critical for maintaining product quality and mitigating defects such as cracks and segregation. Mathematical modeling serves as a fundamental tool for investigation of the dynamics of temperature and solidification front evolution during the process.

A two-dimensional computational model is presented for transient temperature distribution and solidification during the continuous slab-casting process, encompassing both the mold and strand. Full understanding of the complete transient three-dimensional distributions is achieved by simultaneous tracking of multiple transverse strand sections.

The model solves the transient heat transfer equation, incorporating solidification via the Stefan equation to track the solidification front position as an internal boundary. An explicit finite difference method is employed to discretize and solve the equations. To enhance accuracy in fixed cross-section approximation, interpolation techniques utilizing historical temperature data are implemented.

The software system provides a detailed spatial representation of the evolving temperature distribution in transverse cross sections, both as they move with strand and at fixed positions below the meniscus in the mold. It allows evaluation of casting speed variations and secondary cooling parameters, including the spatial arrangement of water nozzles, nozzle types, and spray water flow rates, on strand temperature evolution and shell growth dynamics.

Examples are presented to showcase this computational model and software tool for researchers and engineers to investigate heat transfer and solidification in steel continuous casting.

Speaker: Anna Ivanova (Continuous Casting Centre, Colorado School of Mines)

194 Bending Control With Cooling Bed Technology for Typical Alloy Cold Heading Steel Billet.

During the cooling process on the cooling bed of alloy cold heading steel billet, the quality defect of billet bending exceeding the standard often occurs. In the present work, the reason for its bending is analyzed from the perspective of heat dissipation and phase transition during the cooling process of billet. It is shown that the main reason for the bending of alloy cold heading steel is the billet temperature is too low when transported to the cooling bed. The temperature of the upper cooling bed of the billet can be increased by low superheat, reducing the strength of the secondary cooling or shortening roller residence time of the billet. Production was carried out through the solution provided by present research, and the bending was reduced by more than 90% compared with before the process improvement.

Speaker: Zhiping CHEN (Central Research Institute,Baosteel Iron & Steel CO.,LTD)

195 Finite Element Thermo-Mechanical Modeling of Continuous Casting: Simultaneous In-Mould Solidification and Mould Condition Analysis for High-Speed Billet Casting with Danieli’s Power Mould™

The design of billet moulds fulfills multiple, conflicting, objectives. High productivity at minimal cost remains the primary goal of steelmakers, requiring elevated casting speeds while ensuring optimal surface quality.
The copper mould plays a critical role in the continuous casting process, with its design centered around three key parameters: mould taper, cooling system efficiency, and geometric dimensions. These parameters are inherently interdependent, as the thermal conditions of the mould directly influence strain distribution, actual taper, and mechanical stress states during casting, ultimately affecting mould lifespan, as demonstrated by extensive research ongoing in the past five decades.
Since the 1970s, with the advent of computational modeling, numerical simulation has become an indispensable tool for continuous casting mould design. Computational Fluid Dynamics (CFD) analyses are applied to optimize tundish and submerged entry nozzle (SEN) designs, while thermal and thermo-mechanical FEM simulations are essential tools for mould design and process optimization. As computational power has increased, FEM-based models have evolved to capture the multi-physics complexity of continuous casting, integrating heat transfer, mechanical deformation, and stress analysis with greater accuracy (see VALCRA Seminar, 2020).
Danieli and Transvalor conducted a systematic comparative analysis of two different simulation approaches for mould design. The investigation focused on Danieli’s Power Mould™, an advanced mould configuration optimized for high casting speeds. Danieli's methodology is based on the well-established numerical model developed by Prof. Brian Thomas, implemented within a general-purpose commercial FEM software. Transvalor’s approach utilizes THERCAST®, a proprietary FEM software designed explicitly for solidification and casting, integrating advanced thermal, mechanical, and metallurgical modeling. By systematically evaluating predictive capabilities, computational methodologies, and practical applicability of each approach, the study provides insights into the accuracy, efficiency, and suitability of these tools for mould design.

Speaker: Arianna Gotti (Trasnvalor SA)

196 Secondary Cooling Heat Transfer Measurements on a New Test Rig

The accurate knowledge of the cooling heat-flux in continuous casting spray cooling is essential to exactly control the cooling conditions. Recent investigations on laboratory test rigs by other research groups showed that the cooling heat-flux depends on many parameters and can not sufficiently be described by simple relations between spray water/air density and heat-flux density. In addition to the flow rates, parameters like nozzle type and arrangement, casting speed, surface temperature and orientation as well as the surrounding roll and roll bearing geometries influence the cooling heat-flux. Only measurements on hot surfaces can provide the needed heat-transfer data for each individual cooling situation. A test rig for such measurements developed at PRIMETALS is presented. The test rig consists of a hot plate that can be moved in relation to water nozzles to simulate the strand moving with casting speed. Both nozzles and plate can be rotated to arbitrary angels with respect to gravity to simulate different orientations of the strand surface on a curved caster. Roll dummies can be mounted to analyze the influence of the rolls. The cooling heat flux is measured by applying an inverse modeling algorithm on the time signal of temperature sensors immersed in the hot plate. The design of the immersed sensor is optimized to minimize the inherent errors of the method in order to get accurate results. Process parameter studies are presented to show the influence of the parameters on the cooling effect of the nozzles.

Speaker: Mirko Javurek (Johannes Kepler Universität Linz, Institut für Strömungslehre und Wärmeüübertragung)

Energy Efficiency & Decarbonization

2.2.4

Convener: Mauro Bianchi Ferri (Acciarium)

197 Influence of Hydrogen-DRI on the EAF process

The steelmaking industry, as one of the major emitters of greenhouse gases, is undergoing a transformation towards greener technologies. One of the key players in this transition is the electric arc furnace (EAF), which is fed with scrap and direct reduced iron (DRI), with an increasing proportion of DRI used for high-quality steel grades. Traditionally, DRI production relies on natural gas as a reducing agent. To further reduce the carbon footprint of steel plants, it is planned to partially replace natural gas with hydrogen. However, carbon in the EAF process is not only an energy source but also plays a crucial role in metallurgical reactions, including foamy slag formation, oxygen and nitrogen control. The shift to hydrogen-reduced DRI introduces new challenges, particularly regarding the carbon content of the feed material. Lower carbon levels could impact slag foaming behavior, arc stability, and overall energy efficiency, while also affecting steel chemistry and process dynamics.
This study evaluates the impact of hydrogen-reduced DRI on the entire EAF process, considering factors such as process efficiency, material behavior, carbon footprint reduction, and metallurgical performance. The findings will provide valuable insights into how the steel industry can transition towards carbon-neutral production without compromising process stability and product quality.

Speaker: Leon Heinl

198 Effects of H2 as energy source and biocarbon injection in EAF

The Electric Arc Furnace (EAF) is central for steel industry transformation toward Green Steel production, with ever increasing steel production via the EAF route. However, there are still significant direct fossil CO2 emissions connected to the common EAF operation. Two techniques aimed at reducing direct fossil CO2 emissions from the EAFs are replacing Natural Gas (NG) with H2 as fuel and replacing fossil carbon injection with biocarbon injection. These techniques are being investigated, among others, in the EU-funded Horizon Europe project GreenHeatEAF.
To understand and demonstrate the use of H2 in a Linde CoJet burner and biocarbon injection for slag foaming and slag reduction, pilot trials including 25 heats in the Swerim 10 ton EAF were successfully carried out within the GreenHeatEAF project. Reference heats with synthetic NG as fuel and fossil anthracite injection were carried out during the trials for comparison and evaluation of the effect from replacing NG with H2 and fossil carbon injection with biocarbon injection.
In order to ensure sufficient information for the trial evaluation, 3-5 slag and steel samples were taken at different stages of the EAF operation, together with a dust sample for each heat, numerous temperature measurements, and continuous logging of process data such as power consumption, fuel consumption, material consumption, off-gas analysis etc. These data are then used for stagewise mass- and heat balance calculations in HSC Chemistry to provide a detailed understanding of the EAF process at all stages in the pilot trial heats.
All fossil CO2 from the burners and carbon injection can be avoided without major process changes, according to the successful demonstration of replacing NG as energy source with H2 and fossil carbon injection with biocarbon injection.

Speaker: Mr Joel Orre (Swerim AB)

199 Experimental evaluation of a flexible natural gas and hydrogen burner in the electric arc furnace

In the context of the decarbonization of the steel industry, the electric arc furnace (EAF) has emerged as a primary focus of research. Historically, the EAF has been predominantly utilized in recycling-based steelmaking, specifically for the melting of scrap materials to produce crude steel. The recent surge in research interest in the EAF is driven by the objective of optimizing resource utilization and reducing emissions. Given its primary reliance on electrical energy, the EAF emerges as a promising solution for reducing steel production emissions. In addition to the electrical energy input, the EAF is however equipped with auxiliary burners that avoid ‘cold spots’ during melting and shorten the process duration by increasing the energy input.
These auxiliary burners typically operate as oxyfuel burners, utilizing a mixture of natural gas and oxygen. The combustion of natural gas represents a potential for reducing CO₂ emissions through the substitution with hydrogen burners. In the RFCS-funded project "DevH2forEAF - Developing and enabling H₂ burner utilization to produce liquid steel in EAF," an innovative injector-burner designed for using oxygen and every mixture of natural gas and H₂ (up to 100% H₂) as the fuel was developed for use in EAF, providing a flexible solution for a possible addition of hydrogen to the natural gas line. This injector-burner was subjected to rigorous testing in a range of trials within the environment of an EAF. A downscaled version of the burner, with a power output of 50 kW, was tested in the pilot-scale EAF of the IOB at RWTH, with a particular focus on analyzing its impact on steel quality. Subsequently, a 3 MW burner was installed in two distinct industrial EAFs and utilized in operation. The results of the pilot tests and the two industrial tests are presented in this paper.

Speaker: Lilly Schulte

200 CDRI preheating system by off-gas heat recovery for charging into EAF

Electric Arc Furnace (EAF) steelmaking is a highly energy-intensive process, with substantial heat losses occurring through off-gas emissions. flue gas emissions. The process designed based on our research proposes an advanced waste heat recovery system to enhance energy efficiency by preheating Direct Reduced Iron (DRI) before its charging into the EAF. The system utilizes a high-efficiency heat exchanger to transfer thermal energy from the hot off-gas to a closed-loop nitrogen stream, which then circulates through a specially designed preheating chamber above EAF containing the incoming DRI. This indirect heat exchange mechanism ensures effective thermal energy transfer while preventing oxidation or contamination of the material. After delivering heat to the DRI, the nitrogen undergoes mist eliminator before being recirculated.
By integrating this heat recovery system, significant reductions in electrical energy consumption and tap to tap time can be achieved, and of course, on the one hand, the production capacity is significantly increased, and on the other hand, the consumption rate of refractory and electrode is reduced; as well as improving furnace thermal efficiency and overall process sustainability.
The approach not only optimizes energy utilization but also enhances productivity by pre-heated DRI and improving its reaction kinetics during melting. A comprehensive simulation-based evaluation, including thermodynamic analysis and economic feasibility assessments, has been conducted to quantify energy savings and cost-effectiveness. The results demonstrate a considerable reduction in energy demand, lower CO₂ emissions, and improved process stability, aligning with the industry's transition toward more sustainable and resource-efficient steel production. This study highlights the potential of heat integration strategies in EAF steelmaking and provides a scalable framework for future advancements in waste energy utilization.

Speaker: Mr ALI MOHAMMAD Monfared

201 Efficiency of bio-carbon as slag reduction and slag foaming agent in EAF

As the transition towards green steel production is progressing, the direct use of carbon in the EAF for slag foaming and slag reduction has an increasing portion of the remaining CO2 emissions for steel production. In many cases the total carbon consumption in the EAF is increasing with the increasing percentage of DRI and HBI in the charge material mix. It is therefore important to minimize the use of fossil carbon as input material to the EAF. The use of bio-carbon for this purpose is investigated in the EU-funded Horizon Europe project GreenHeatEAF.

To investigate the efficiency of bio-carbon in relation to anthracite in terms of carbon yield to reduction of metal oxides in slag as well as the comparative effect on slag foaming, pilot trials in the Swerim 10 ton EAF was carried out within the GreenHeatEAF project. The trials consisted of 25 heats with varying charge materials (scrap, DRI and HBI) and different charging strategies (bucket charging and continuous feeding). Anthracite and highly pyrolyzed bio-carbon (89 % C and <5 % volatile matter) was used as injection-carbon with the target to achieve the same FeO-content in the slag.

Slag and steel samples were taken on 3-5 occasions during each heat at different stages of the process to evaluate the carbon yield during different conditions. Together with material composition data, temperature measurements and logged process data, a stagewise mass- and heat balance model developed in HSC was used to evaluate the carbon yield.

The evaluation of the trials showed that the anthracite for slag-foaming and slag reduction can be fully replaced with bio-carbon, although the yield of C in the investigated bio-carbon to reduction of metal oxides in the slag was about 20-25 % lower than for C in anthracite.

Speaker: Erik Sandberg (Swerim AB)

Energy Efficiency & Recovery

5.3.4

Convener: Matteo Marten-Perolino (AIM)

202 Energy recovery in long product casting

Energy recovery in the continuous casting process offers substantial opportunities for enhancing efficiency and sustainability within the metals industry. During the solidification and cooling phases, a significant volume of energy is extracted from the melt. This energy, however, is often dissipated and remains unrecovered, representing a lost opportunity for energy optimization. Recognizing this, SMS Concast has identified several promising areas within the continuous casting machine where energy recovery could be effectively implemented.

One primary area for potential energy recovery is the mold cooling system. In continuous casting, the mold cooling water absorbs a considerable amount of heat from the molten metal as it begins to solidify. By implementing advanced heat exchange systems, the thermal energy from the cooling water can be captured and repurposed, potentially reducing overall energy consumption in the plant.

Another area of focus is the heat radiation above the turnover cooling bed (TOCB). As the cast product moves along the cooling bed, it emits a significant amount of radiant heat. This energy can be harnessed using innovative technologies such as thermoelectric generators or heat exchangers, converting the radiant heat into usable electrical or thermal energy.

The implementation of energy recovery systems in these areas not only contributes to reducing energy costs but also aligns with broader sustainability goals by minimizing the environmental footprint of the casting process. Moreover, the recovered energy can be redirected to other processes within the facility, enhancing overall operational efficiency.

By focusing on these key areas, SMS Concast aims to lead the way in developing sustainable solutions for the metals industry. Through strategic investment in energy recovery technologies, the continuous casting process can be transformed into a more energy-efficient and environmentally friendly operation, ultimately contributing to a more sustainable future for the industry.

Speaker: Dr Gian Hauenstein (SMS group)

203 Optimizing Energy Media Consumption and Reducing Greenhouse Gas Emissions in Coil Coating Lines

The global push to counteract climate change has led policy makers to introduce stringent measures aimed at mitigating greenhouse gas (GHG) emissions. These efforts, combined with volatile energy media prices (electricity, natural gas, etc.), have intensified the search for innovative solutions to optimize energy consumption and recover residual energy from industrial processes. Key objectives include minimizing environmental impact and reducing GHG emissions in compliance with Scope 1 and Scope 2 emission standards.
In response to these challenges, Danieli FATA Fröhling has pioneered new solutions, focusing on both new installations and the revamping of existing coil coating lines. The company's efforts center on reducing energy consumption across critical operational stages while implementing advanced recovery systems for residual energy in exhaust streams. These measures aim to enhance efficiency, reduce dependency on primary energy sources, and lower the carbon footprint of production lines.
Investing in innovative technologies is at the core of Danieli market approach to support its customers in producing high added value products with higher profitability. The New Digital Printer is one of those, a revolution in construction, home appliance, transportation and advertising market.
This work provides a comprehensive overview of the strategies developed and implemented by Danieli FATA Fröhling. It highlights some state of the art projects that demonstrate successful optimization of media consumption, including the application of cutting-edge energy recovery technologies, by addressing the benefits of these initiatives, such as reduced operational costs, improved sustainability, and compliance with evolving regulatory frameworks.
By showcasing practical applications and measurable outcomes, this work offers valuable insights to stakeholders in the industrial sector by drawing attention to the critical role of technological innovation in advancing energy efficiency and climate resilience in manufacturing processes.

Speaker: Mr Michele Chiappa (Danieli & C. Officine Meccaniche S.p.A.)

204 Volteron - Technology for Green Steel

VOLTERON™, an innovative technology developed by John Cockerill and ArcelorMittal to achieve carbon-neutral steel production through direct iron electrolysis. This process represents a significant breakthrough in primary steelmaking by employing low-temperature electrowinning in an aqueous-based electrolyte, moving away from conventional blast furnace and basic oxygen furnace (BOF) methods, which are major contributors to global CO₂ emissions. VOLTERON™ technology is designed to transform iron oxide (Fe₂O₃) directly into pure iron metal plates using electricity, effectively eliminating CO₂ emissions associated with carbon-based reduction methods. VOLTERON™ builds upon the findings from the SIDERWIN project, a Horizon 2020 EU-funded initiative, which has successfully demonstrated its potential at a pilot scale, with energy consumption and production efficiency meeting expected benchmarks. The process operates at a low temperature of approximately 110°C, which is significantly lower than traditional steelmaking temperatures, allowing for substantial energy savings with a consumption rate of approximately 3.6 MWh per ton of steel produced. The use of a vertically oriented cell design with industrial-scale cathode dimensions enhances scalability and efficiency, making the process suitable for large-scale deployment. VOLTERON™ offers a marked reduction in both energy usage and greenhouse gas emissions compared to alternative decarbonization routes, such as hydrogen-based direct reduction (DRI) or carbon capture and utilization (CCU) methods. Its ability to utilize standard iron ore without extensive pre-processing enhances its economic feasibility, positioning it as a leading solution in the global push for decarbonized steelmaking.

Speaker: Mr David Michel

205 Optimized Control of an EAF off-gas system by Video Analysis

Gas cleaning and dedusting systems are essential for any steelmaking facility, but they often face significant fluctuations in operational requirements. Emissions can vary based on different input materials or product mixes, necessitating adjustments in the dedusting system’s operation. Manual optimization by operators is challenging due to fluctuating operating parameters, and furnace underpressure measurements used as control signals often suffer in the rough working environment.

To address these inefficiencies, an intelligent sensor system based on video analysis was developed. This innovative system uses advanced video analysis techniques to monitor and optimize dedusting systems in real-time.

Implemented at an Electric Arc Furnace (EAF) for stainless steel production, the system continuously analyzes video data to detect and respond to fluctuations in operational parameters more accurately and efficiently than existing sensor technologies. This ensures peak efficiency, reducing energy consumption and improving overall performance.

Initial results show improvements in energy efficiency and operational effectiveness. The achieved savings and enhanced control over emissions will be presented to demonstrate the system’s capabilities. These results highlight the potential for widespread adoption of video-based intelligent sensor systems in the steelmaking industry, paving the way for more sustainable and efficient operations.

Speaker: Thomas Steinparzer (Primetals Technologies Austria)

206 Optimizing Process Gas Utilization through AI: A Sustainable Energy Solution

The transition toward a low-carbon, sustainable industrial ecosystem requires innovative solutions that maximize resource efficiency and minimize environmental impact. This study presents EnVisA, a research project funded by Vinnova, Sweden, focused on optimizing the utilization of process gases from steel production through advanced AI-driven tools. Despite the high calorific value of these gases, a significant portion remains underutilized or flared, leaving a great opportunity for improving energy recovery. EnVisA addresses this challenge by developing predictive models to forecast surplus gas availability and integrating real-time visualization systems to enhance operational decision-making. To realize this target, the project focused on enhancing the cooperation between different sectors from steelmaking to local energy system in the framework of Industrial Symbiosis. As a result, the outcoming real-time prediction and visualization system has been launched in the industrial trial to facilitate the integration of process gases into local energy systems and promote energy efficiency.
EnVisA’s work aligns with the framework of the ongoing EU RFCS project SymbioSteel, which focuses on Industrial Symbiosis. It aims to transform the steel sector by promoting collaboration with other all stakeholders and reducing environmental impact and accelerate the adoption of Industrial Symbiosis in the steel industry, supporting decarbonization and resource efficiency. SymbioSteel provides a robust platform to evaluate project’s performance on industrial symbiosis development, emission reduction, resuource efficiency, etc.
After EnVisA project was completed, it was evaluated with idea and methodologies from SymbioSteel, resulting in deeper insights into the potential of EnVisA for energy saving, environment protection and sustainable development. This will enable us to refine EnVisA's strategies and set plans for future development.
Keywords: Process gas; Energy recovery; AI prediction; Industrial Symbiosis; Steelmaking.

Speaker: Dr Han Yu (Metallurgy department, Swerim AB)

Hydrogen-Based Steelmaking Technologies

5.2.1

Convener: Ismael Matino (Scuola Superiore Sant'Anna - TeCIP Institute - ICT-COISP)

207 Innovative Approaches To Sustainable FeCr Production Through Biocarbon and H2 Utilization

Ferrochromium (FeCr) alloy is essential in the production of stainless steel and specialty steels. The urgency for sustainable production methods is increasing due to the rising carbon footprint. One promising solution is incorporating biocarbon as a partial substitute for coke in submerged arc furnaces (SAF), while also maximizing the recycling of iron-bearing materials, such as mill scale from the special steel industry. Additionally, utilizing H2 as a reducing agent for iron oxides can significantly lower carbon consumption and mitigate fossil CO2 emissions. Exploring the potential for the partial reduction of chromite ores further enhances these sustainability efforts.
In this study, biocarbon-chromite briquettes were developed on a technical scale using vibro-press and roller press techniques to optimize carbon content. Various binders and additives were employed to achieve optimal results. It was possible to reach 10% biocarbon in vibro-pressed briquettes and 20% in roller-pressed briquettes without compromising the briquette`s quality. The briquettes underwent mechanical strength evaluation and were subsequently processed for reduction using H2. The reduction process was analyzed through thermogravimetric analysis coupled with quadrupole mass spectrometry (TGA-QMS) at temperatures up to 1100°C. Results indicated that H2 effectively reduces mill scale, primarily composed of FeO, within the temperature range of 600°C to 750°C, while biocarbon enhances the partial reduction of chromite ore (FeCr2O4) at higher temperatures.
This research is part of the FEMOST project, supported by a consortium that includes Swerim, Vargön Alloy AB, Future Eco, Uddeholms AB, Ovako Sweden AB, and RISE AB, and is financed by the Swedish Energy Agency. This study contributes to advancing sustainable practices in the FeCr industry through these innovative approaches.

Speaker: Elsayed Mousa (Swerim AB)

208 Challenges and solutions for process characterisation of hydrogen plasma smelting reduction (HPSR) at pilot scale and beyond.

Hydrogen plasma smelting reduction (HPSR) is an emerging low-CO2 technology which can accomplish steel production from iron ore in just a single step. This is done using a high-power DC-transferred plasma arc generated between a hollow graphite electrode, which conveys the hydrogen gas into the reactor, and an iron-containing molten oxide bath. This plasma arc serves as both the primary furnace heat source and creates high temperature, highly reactive hydrogen species which accomplish the metal reduction. The extreme thermal and radiative conditions of the arc as well as the harsh thermochemical properties of the oxidic melt make process monitoring and on-line characterisation difficult to accomplish. Any engineering solutions are even further complicated by the closed-system operation which is a necessary safety measure in the operation of high-H2 atmospheres.
Solutions to these challenges of process characterisation have been vital in the optimisation and development of a first-of-its-kind pilot-scale HPSR plant operated by K1-MET GmbH at voestalpine Stahl Donawitz, Austria. The collection of low-latency, high-resolution data have provided a means to understand process failures, describe behaviours, and investigate system models. Computational tools and the identification of optimal parameters can allow the creation of process control routines and help maintain operational stability. These measurement solutions include: the collection of visual data in the form high speed imaging and optical emission spectroscopy; high resolution electronic characterisation of arc voltage and current; temperature measurement of the molten bath; and sampling of the metallic and slag fractions of the molten bath.
Insight into the innovative characterisation solutions will be discussed in the context of these challenges, referring to system constraints, technology gaps, and scientific unknowns, with a view to industrial-scale implementation beyond TRL 6. The technologies and tools shown demonstrate the importance of multidisciplinary approaches to achieve rapid development and meet global goals of industrial decarbonisation.

Speaker: Cameron Quick (K1-MET GmbH)

Rolling Mill Technology & Process Optimization

3.1.1

Convener: Caiyi Liu (Yanshan university)

209 Innovative Rolling Mill for Seamless Structural Hollow Sections - The legacy of MSH profiles continues

Although the production of ERW (electric resistance welded) square and rectangular sections is well-established, certain applications require seamless square and rectangular hollow sections due to their superior properties. These products' limited demand capacities make the market closely linked to downstream value chains, where their availability is crucial, as ERW tubes have neither been extensively tested nor approved.

After being balanced for decades, shifts on the supply side threatened to remove a significant portion of these products from the market. These were produced by a sophisticated hot rolling process that ensured strong structural properties. The so-called MSH profiles, which include circular, square, and rectangular structural hollow sections, were widely used in various applications, including construction, mechanical engineering, and offshore structures, due to their versatility and strength.

To counteract the risk of shortcoming, companies like voestalpine Tubulars are expanding their capabilities in this area. Together with KOCKS as an experienced special plant manufacturer, an ambitious project was initiated to develop an innovative four-roll profiling mill designed to produce seamless, hot-rolled square and rectangular hollow sections. This mill was strategically installed after an existing stretch reducing mill, leveraging the efficiency of the existing setup while enhancing production capabilities without requiring major relocation of equipment.

The paper puts focus on the main drivers, motivations and challenges in line with this plant project in an evolving industrial landscape from a technical viewpoint. The application will be described in detail as part of a best practice including its respective benefits. And, given the high importance of those products in downstream value chains, it shows how the legacy of MSH profiles continues to influence the development of new structural hollow sections.

Speaker: Jörg Surmund (Friedrich KOCKS GmbH CO. KG)

210 Low-emission, multiline, quality bar quenching and tempering lines: Danieli Olivotto Ferré multiline solution maximizes production capacity and final product quality

The latest trends in the premium automotive steel bar market focus on meeting the highest quality standards demanded by end users. Achieving these targets relies heavily on advanced heat treating technologies, which are crucial for attaining the desired metallurgical and mechanical properties. These new technologies must also contribute to reducing fuel consumption and emissions.
The new Danieli multiline system, featuring inclined and shaped rolls, enables continuous rotation of bars during their handling inside the austenitizing furnace and the quenching machine. This continuous rotation enhances the homogeneity of the bars and minimizes the risk of deformation.
This innovative solution is further optimized by strategic arrangements of burners in the furnaces and water or water/polymer spray nozzles in the quenching machine. These adjustments ensure excellent treatment uniformity, resulting in a high-quality final product.
Danieli's proprietary hydrogen-ready burners and combustion design system offer a significant reduction in fuel consumption and emissions. Specifically, this system achieves a 25% reduction in fuel consumption and emissions, with the potential for carbon emissions to reach zero when using 100% hydrogen.
Currently, two lines featuring this cutting-edge technology are operational, consistently producing treated bars that exceed EN 10083 requirements. A third line is currently in the engineering phase, promising to further enhance production capabilities and quality standards.
In summary, these innovations not only meet stringent end-user requirements but also contribute to environmental conservation by significantly reducing fuel consumption and emissions. The integration of advanced heat treating technologies and hydrogen-ready combustion systems in the premium automotive steel bar market is setting new benchmarks for quality and sustainability.

Speaker: Andrea Barberis (Danieli & Officine Meccaniche S.p.A.)

211 A New Technology for Bar and Wire Rod Mills

The eDrive Mini-Finishing Mill by Primetals Technologies offers significant advantages for bar-in-coil and wire rod mills, including reduced CAPEX and OPEX, lower power and water consumption, and enhanced operational flexibility with quick product size changes. Its low-voltage system, virtual gear box, and reduced maintenance needs improve efficiency. Compared to other technologies on the market, it delivers 10-15% higher stand capacity, uses smaller motors due to helical gear ratios, and features interchangeable rolling stands with no orientation constraints. These enhancements, combined with integrated control for faster impact compensation, make it a cost-effective and reliable solution for quality steel production. This paper will dive further into the technology while referencing its recent successful implementation within a combination bar-in-coil and rod mill located in Baosteel, China.

Speaker: Stephen (Mark) Shore

Blast Furnace Decarbonization

5.2.2

Convener: Ismael Matino (Scuola Superiore Sant'Anna - TeCIP Institute - ICT-COISP)

212 Hydrogen Pulse Injection into the Blast Furnace Shaft

As part of the 2030 Climate Target Plan, the European Union has set a target of reducing green-house gas emissions by 55% and becoming carbon neutral by 2050. The use of hydrogen will be the backbone of the steel industry's transformation towards carbon neutrality. In the long term, for the vast majority of the roadmaps communicated by the various steel producers, the technical solution will be to replace the traditional blast furnace plants with direct reduction plants using hydrogen. However, due to global economic constraints and limitations on the availability of green electricity and hydrogen, as well as the fact that BFs have campaign lengths of 10-20 years, these roadmaps for CO2 abatement still include a large proportion of the BF process even beyond 2040. Consequently, technologies to reduce the carbon footprint of blast furnace ironmaking are also needed as bridging technologies. In the short to medium term, hydrogen injection is widely discussed as a way to reduce CO2 emissions from BFs.
Hydrogen injection at the tuyere level has already been successfully tested, but has some drawbacks. For example, the hydrogen competes with pulverised coal for available oxygen and resulting flame temperatures with hydrogen are high, resulting in higher heat loads near the tuyere tip. It is believed that injecting hydrogen at shaft level has the potential to mitigate such effects and could even lead to higher gas utilisation rates. Based on these considerations, a consortium of research and industry partners has been funded by the European Commission to evaluate and demonstrate the potential of sequence impulse injection of hydrogen into the blast furnace shaft. This article presents the concept of sequence impulse shaft injection of hydrogen, as well as initial results from injection depth trials on a demonstration scale test rig.

Speaker: Hauke Bartusch (VDEh-Betriebsforschungsinstitut GmbH)

213 The groundbreaking concept of Carbon Neutral blast furnace, called SimpLE

The blast furnace (BF) is the most energy-efficient iron-making process but faces significant challenges in the carbon neutral (CN) movement. To address this, we’ve developed a groundbreaking concept of CN BF, called SimpLE (Smart iron-making process for Low Emissions).
In Step 1, SimpLE aims for a near-zero Coke Rate (CR) through smart charging, smart reduction, and smart combustion. The SimpLE BF combines a DRI process with an oxygen melter, featuring three-stage tuyeres and top gas recycling with an external-fuel reformer (existing hot stove). Three-stage tuyeres enable central flow operation and achieve almost 100% gas-reduction (Smart reduction) without coke gasification/degradation or sinter degradation. Burdens are mixed and charged in layers according to particle size (Smart charging). Smart charging and smart reduction lower the cohesive zone head loss by 6/7, reduce the heat load in the lower furnace by 2/3, and make the unburnt pulverized char (UPC) consumed in the lower furnace (Smart combustion). Accordingly, compared to conventional BFs, SimpLE will reduce carbon input by 40 to 50% and enable near-zero CO2 emissions (80% reductions) with CO2 recovery, while maintaining the equivalent net heat consumptions.
In Step 2, SimpLE will preprocess relatively available but impure renewable fuels, such as municipal wastes, to substitute metallurgical coal by means of distillation and chloride volatilization in the coke ovens that will acquire surplus production capacity by near-zero CR. This approach will enable near-zero fossil-derived carbon input far more energy-efficiently than any other iron-making process and will realize negative emissions of 30% or more with CO2 recovery compared to conventional BFs. Additionally, it will drastically improve the heat efficiency of municipal wastes including CO2 recovery, reducing the total net heat consumptions of iron-making and its society. Renewable fuels can be substituted by e-fuels with less priority, particularly because e-fuels or hydrogen require tremendous primary energy.

Speaker: Takeshi Sekiguchi

214 Decarbonization by Process Optimization - Off-Gas Results Using Deep View Infra-Red Technology

The infrared exhaust gas measurement system for electric arc furnaces and similar ovens has been successfully established on the market for 2.5 years. Initial long-term results are now available, demonstrating the system’s reliability and effectiveness. The new function tested at the ESF steel plant in Riesa, Germany, is the ability to measure CO content of the furnace gas under the roof of the furnace with a sensor installation on the D2 duct. By this the CO concentration in the offgas duct as well as under the roof can be measured simultaneously with only one sensor location on the offgas duct.

Speaker: Ms Alexandra Graf

Roll Technology & Maintenance

3.1.2

Convener: Caiyi Liu (Yanshan university)

215 The Effect of Ferrovanadium as an Inoculant Using in HSS Rolls using in light section mills

High speed steel rolls (HSS) have replaced the traditional high chromium iron rolls (HCI) in many hot strip mills and acicular rolls in log products mills showing very good results for quality and productivity improvements. This paper describes The effect of ferrovanadium inoculation on the microstructure and properties of high speed steel (HSS) used for light section mill was studied. The results showed that the as-cast eutectic carbide network tends to be broken after ferrovanadium inoculation, and the carbides are changed to rod-like or nodular shape. After heat treatment, the carbides in the inoculated HSS are spheroidized and distributed more uniformly in the matrix. The impact toughness of high speed steel with ferrovanadium inoculation is obviously improved. The action mechanism of ferrovanadium inoculation on the microstructure of the alloy is also discussed

Speaker: Adel Sheikhhosseini (Behin Industrial Group)

216 The investigation on generating a new sleeve grade using in initial stand of Rebar rolling Danieli mills for improving fracture toughness of coupling

Sleeves using in initial stands of rebar rolling in danieli mills are cast iron or ferritic cast iron generally. Application of this material meet the demands of mills especially wear resistant and reduction of fire cracks. But in some cases mills face problems in coupling fracture in sleeves. Cast irons have lower fracture toughness ratio to steels grade. Although steel grades have lower resistant to fire cracks. In this investigation we introduce a new steels grade to fulfill the needs including wear resistant, fire cracks resistant and improving and stability of performance and machinability as well. this new grade is steel base grade with special heat treatment which improve the performance about 25-30% without any coupling fracture in two Danieli mills.

Speaker: Adel Sheikhhosseini (Behin Industrial Group)

10:40 Coffee break

Alloy Design & Microstructure Control

4.1.1

Convener: LUIGI CHINAGLIA (FOMAS S.p.a.)

217 Predicting recrystallization phenomena with DIGIMU during hot-rolling of grade AISI 304L

Customers are more and more demanding for fine and homogeneous grain sizes in hot-rolled bars and wire rods dedicated to technical applications such as aeronautics, medical or watch-making. To assess those requirements, UGITECH is interested in using recrystallization models to better understand and predict the effects of both process parameters (like temperature, strain and strain rate) and metallurgical characteristics (chemical analysis, phase transformations, …) on product microstructure evolution throughout its whole hot-rolling route. In this context, DIGIMU software, developed by TRANSVALOR, has been tested in the case of stainless steel AISI 304L.
Firstly, material input parameters of DIGIMU model related to grade AISI 304L (strain hardening, recovery, grain growth, dynamic and post-dynamic parameters) were identified through several series of laboratory hot-torsion tests carried out for various temperature (between 1000 and 1250°C), strain (up to 2) and strain rate (between 0,1 and 10s-1) ranges.
DIGIMU model was then used to predict microstructural evolutions during hot-processing of AISI 304L stainless steel in the following conditions:
- Laboratory single pass hot-rolling with different re-heating temperatures and roughing rates.
- Industrial multi-pass hot-rolling focused on UGITECH roughing mill stands.
In each case, DIGIMU results have been compared to experimental ones in terms of microstructure topology, recrystallized fraction and grain size distribution. Lab hot-rolling conditions with fast cooling rates were proned to generate different microstructures, from the onset of new grain nucleation up to complete recrystallization. Microstructure evolutions were shown to be well predicted by the full-field model.
Finally, local solute-drag effect (based on Cahn’s approach) was integrated into the model to improve the consistency between experimental and predicted grain sizes, in both laboratory and industrial hot-rolling conditions.

Speaker: Thomas Sourisseau (UGITECH)

218 Effect of short-time annealing on recrystallization and texture evolution in an electrical steel

The study focuses on the study of the static recrystallization and texture evolution of an electrical steel annealed at three different temperatures for sub-minute soaking time. The objective is to determine the optimal time-temperature parameters that promote the development of favourable crystallographic textures for magnetic properties while minimizing annealing time. Microstructural evolution and texture formation were analysed using Optical (OM) and Scanning Electron Microscopy (SEM), and Electron Backscatter Diffraction (EBSD). Unlike conventional studies conducted in controlled atmospheres, this work investigates recrystallization in ambient air, providing insights into its feasibility for industrial-scale applications. The findings demonstrate the potential for achieving desirable textures through rapid annealing in non-controlled environments, providing a pathway for process optimization in electrical steel manufacturing.

Speaker: Dr Daniele Carosi (Alma Mater Studiorum - Università di Bologna)

Blast Furnace Decarbonization

5.2.2

219 The SMART project : recycling of plastics and waste materials in TORERO to substitute more coal injection in the blast furnace

The SMART acronym stand for “SteelMaking with Alternative ReductanTs”. This project aims at using local waste-based non-recyclable resources in steelmaking, and to do it in such a way that their intrinsic chemical value is fully recovered, thereby reducing the need for conventional reductants (fossil coal) and enabling a substantial reduction of CO2 emissions.
The main technical options considered for charging the waste materials in the steel plant are either the direct feeding to the coke ovens (mixed in the coal blend) or the processing in the TORERO plant to produce a torrefied material (“biocoal”) that can then be fed to the blast furnace as substitute to PCI coal. Various initial waste streams are considered.

Regarding the torrefaction step, the main development tasks of the SMART project are on the adequate selection and preparation of waste materials and then on the tuning of the torrefaction technology. The different waste streams were characterized at lab in order to identify the relevant ones and torrefaction trials of small batches were achieved at CRM. First pilot torrefaction trials with blends of waste materials and B-wood are under way and will provide the expected support for the future industrial development in ArcelorMittal Ghent.

The project SMART is co-funded by the LIFE Programme of the European Union (LIFE19CCM/BE/001215). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or CINEA. Neither the European Union nor the granting authority can be held responsible for them.

Speaker: Damien Garot (CRM Group)

220 150 tons revert-based briquettes produced and processed in a blast furnace

The sinter plant plays a key role in processing internal by-products and waste materials from various processes within the steelmaking industry. However, sinter making is energy intensive, with no 100% green alternative, leading to substantial CO2 emissions. As a results, the sinter plant is not utilized in future green scenarios. An alternative could be found in cold bonded briquetting: a practical bridging option for both internal circularity and CO2 reduction.

Cold bonded briquetting was studied in the COACH (Cold bonded agglomerates for Blast Furnace ironmaking with chemically engineered binders) project, EU-funded by RFCS. It focussed on the preparation and assessment of cold bonded briquettes from reverts, initially with tailor made, polyamide based binder for blast furnace ironmaking.

Two reverts were selected for making the briquettes: classifier sludge from the steelshop and so-called bunker-dust from the blast furnace. The finer dust from the blast furnace in combination with the coarser dust from the steelshop resulted in acceptable strength due to optimized particle size ditribution. The briquettes were produced at the pilot plant for extrusion at Tata Steel Netherlands. The produced briquettes were characterized by testing their green strength, cold strength and metallurgical strength. It was found that particle size distribution and moisture content of the raw material were key for a high performing briquette.

A total of 150 tons of briquettes were produced, cured on the field for several weeks, and subsequently transported to the blast furnace. During a 10-hour trial, the briquettes were burdened during regular blast furnace operation. No evidence was found that the briquettes had a negative impact on overall operation or dust production.

Speaker: Joyce den Hollander

221 Blast Furnace CO2 Emissions: A Techno-Economic Assessment

Decarbonization is a key strategic objective for the steel industry. Despite the growing interest in DRP-EAF steelmaking, BF-BOF steelmaking is anticipated to remain dominant due to its efficiency, economic benefits, and constraints associated with DRP-EAF. Therefore, it is essential to focus on reducing CO2 emissions from blast furnaces. This paper provides a detailed techno-economic assessment of the most effective and immediate strategies to achieve significant reductions in BF CO2 emissions.

Speaker: Reinoud van Laar (Danieli Corus BV)

2025 ESTAD - BF CO2 Emissions Techno-Economic Assessment.pdf

222 Blast Furnaces CO2 mitigation: Ekofor technology (E.S.C.H. gmbh) for BLUAIR injection (Secondary Raw Material - recycled polymers)

In the steelmaking, integral cycles will face important investments for decarbonization, that will hardly get paid in the short term due to market outlook (dumping, weak border barriers, high energy costs…). In this context, ESCH and I.Blu are cooperating in some BFs ensuring reliable and continuous injection of BLUAIR, a high quality Secondary Raw Material recycled from polyolefins feedstock of domestic household collection which allow an immediate cut of -30% CO2 reduction on the direct emissions coming from coal (PCI) injected from BF tuyeres. 12% of Hydrogen content and Lower Calorific Value of 35MJ/kg (compared to 26-28MJ/kg of PCI) are also beneficial to reduction process of BFs. BLUAIR is widely available, already spread across the market, and decreases by 20% PCI consumption in Blast Furnaces. ESCH gmbh has been the first company in Europe to engineer, in addition to traditional PCI injection plants, a tailor-made injection equipment for alternative reductants in Blast Furnaces, named Ekofor, which is able to provide a flexible and affordable injection solution with a low “time to market” approach, low payback period, which can guarantee stable KPIs on the process. PCI plant and Ekofor injection technology for polymers can be flexibly adapted to improve BF Process and OPEX costs for raw materials. Ekofor injection plant is available as follows:
• Ekofor Pilot plant: is a flexible, plug and play, rental solution which is able to allow receival of BLUAIR loose, load a special vessel distributor tailor made for BLUAIR with 3 outlets, and guarantee a low injection rate around 1,5-2ton/h depending on BF operation, allowing approximately -10kgCO2/tonHM for AVG BF
• Ekofor Industrial plant: reliable, affordable and industrial solution which can guarantee a high injection rate of BLUAIR, 25 to 50 kg/tonHM, replacing 20% of PCI injected, equal to -50kgCO2/tonHM for AVG BF

Speakers: Dr Daniel Kaulbars, Elia Gosparini

Estad2025_COPYRIGHT_ASSIGNMENT_STATEMENT.docx

Estad2025_COPYRIGHT_ASSIGNMENT_STATEMENT.docx

Final_Paper_I.Blu&ESCH.docx

Burden Materials & Quality

1.3.2

Convener: Prof. Davide Mombelli (Politecnico di Milano - Dipartimento di Meccanica)

223 Sodium silicate impacts on blast furnace operation.

This study explores the main differences between Na and K on the Blast Furnace operation focusing on the effects of Na₂SiO₃. The experimental method involved simulating thermodynamic parameters comparing traditional alkalis oxides, carbonates and silicates. In addition, a technological apparatus was used to describe slag properties and gangue phases at high Na content. The results indicated that differently from Na and K oxides and carbonates, Na2SiO3 compound is completely stable in blast furnace atmosphere which promotes low probability for reducing this compound to Na vapor. Furthermore, the study investigated Na vapor adsorption by iron-containing burdens. Sodium was vaporized from Na₂CO₃ and Na₂SiO₃ at 1200°C, and the results showed that Sodium was adsorbed by sinter and pellet samples from Sodium Carbonate, but not from Sodium Silicate. In addition, It was observed Na2SiO3 compound could be removed by the slag with typical chemical parameters of a Blast Furnace. Finally, the slag physical chemical properties was not affected by Na₂SiO₃ addition as seen, the slag viscosity decreased when increase Na content via sodium silicate compound.

Speakers: Mr AUGUSTO PEREIRA DE SÁ (VALE SA), FABIO ROCHA DA SILVA (VALE SA), Dr MARCUS EMRICH (VALE SA), Dr VINICIUS MORAIS DE OLIVEIRA (VALE SA)

224 Comparison of laboratory tests and HKM blast furnaces on the reduction and carburisation behaviour of burden materials under coke gas injection

Keywords: CO2 reduction, Blast Furnace, Coke Oven Gas, Green steel, Hydrogen containing injectants, Iron oxide reduction

By developing decarbonisation plans, the European steel industry shows its commitment to the European climate change targets. The main element in these plans is a transformation step involving a transition from carbon-based blast furnaces to green hydrogen-based direct reduction processes. This will take place around 2030 and will result in significant CO2 reductions.Hüttenwerke Krupp Mannesmann (HKM) has already taken measures to reduce CO2 emissions.

As already presented at the 8th and 9th ECIC in Bremen and Bardolino, HKM has upgraded its systems to inject compressed coke oven gas (COG) at the two blast furnaces “A” and “B”. Since the injection station was commissioned in June 2023, HKM has been able to inject more than 250 million Nm³ of hydrogen at a continuous injection rate up to 45 kg/tHM, saving more than 300.000 tonnes of CO2.

This article discusses the effect of COG on blast furnace burden materials. For this purpose, the effect of hydrogen-containing gases on the reduction and carburisation behaviour was investigated and compared in laboratory tests at the BFI in Düsseldorf. These results will be used to improve the understanding of the metallurgical process and the effect of coke oven gas on blast furnace performance. As a result, the use of coke oven gas can further contribute to the reduction of the CO2 footprint of HKM crude steel.

Speaker: Dr Fabian Perret (Hüttenwerke Krupp Mannesmann GmbH)

225 Development of Degradation Model for Sinter Ore Considering Particle Size Distribution

In recent years, reducing CO2 emissions in the steel industry has been demanded from an environmental conservation perspective. As a partial substitute for coke, a reducing agent injected into the blast furnace, the injection of H2 is being considered. The reduction reaction of ore by H2 is an endothermic reaction, and there is concern about a decrease in the temperature inside the blast furnace. If this occurs, there is a risk that the degradation of ore particles will worsen in the low-temperature region inside the blast furnace. Therefore, this study aims to estimate the size distribution of ore during reduction based on population balance model. Until now, prediction models for sinter ore after reduction have mainly been evaluated using only CO as the reducing gas, and the relationship between the harmonic mean diameter and the reduction rate has been studied. However, with prediction methods based solely on the harmonic mean diameter, it is not possible to estimate the amount of fine ore, which has a significant negative impact on the permeability inside the blast furnace. Therefore, an attempt was made to understand the amount of disintegration through the formulation of particle size distribution after reduction. Sinter ore was used for the experiments, and the reduction atmosphere was set as CO-H2-N2. The reduction temperature was set at 450-800°C. Additionally, the influence of H2 gas on degradation was also studied by conducting experiments under CO gas, CO-H2 mixed gas, and H2 gas. By organizing the data using the Gaudin-Meloy distribution, it was possible to calculate parameters that indicate the particle size distribution after reduction, regardless of the gas composition and temperature.

Speaker: Kazuto Nishihiro

226 Influence of the mineral gangue on pellets softening melting properties in Blast Furnace. Experimental study of phase equilibria during the melting of pre-reduced pellets

The progressive decarbonization of the steel industry is being undertaken through the transformation of Blast Furnaces (BF) and by limiting the quantity of coke.
The reduction of coke rates may impact the permeability at the Cohesive Zone (CZ) level, a viscous and impermeable layer resulting from the softening and melting of Iron Ore. The control of this CZ, its shape, thickness, and permeability, is essential for the proper functioning of BF. The use of adapted raw materials, i.e. their softening melting properties, is an indirect way to control the CZ and to increase permeability.
In this study, we experimentally investigated the melting of different Iron Ore pellets linked to their chemical compositions (acid and fluxed pellets). Pellets were pre-reduced in the counter-current reduction pilot BORIS in conditions representative of BF up to 1000°C. Reduced pellets were then melted using different tools: differential thermal analysis (DTA) and a quenching furnace.
Results make it possible to better understand the behavior of pellets in a BF and confirm that the use of basic pellets is preferable to acid pellets. The amount of liquid inside basic pellets remains low up to higher temperatures, which promotes mechanical properties and better reductive gas distribution. This also imply a deeper and thinner CZ.
Attention was paid to the microstructure (nano scale) as the deformation of reduced materials is triggered by the partial melting of pellets and the formation of primary slag. Results also indicate that thermodynamic modeling could be a suitable and rapid tool to anticipate the behavior of different pellets at the CZ level of blast furnaces. Thermodynamic databases must, however, be adapted to better model the real phase equilibria, representative of pellet melting.

Speaker: Yann Graz (ArcelorMittal research)

227 Cold Agglomerated Iron Ore Briquettes for Blast Furnace: Refractory Performance of Runner and Mud Gun

According to the World Steel Association, the steelmaking chain is responsible for almost 8% of global CO2 emissions. In this context, a new product has been developed: a cold agglomerated briquette composed of iron ore fines that significantly reduces its carbon footprint, contributing to the decarbonization of the steelmaking chain. The developed binder technology, based on sodium silicate, allows the production of a briquette with the physical, chemical, and metallurgical characteristics needed for the Blast Furnace (BF). This material has properties comparable to high-performance ferrous burdens, such as pellets and sinter, and can reduce CO2 emissions in the BF process by up to 10% when it replaces these materials. The technology has been proven through industrial trials, demonstrating the stability of sodium silicate at high temperatures and excellent sodium purge levels by the BF slag. To better understand the impact of this new technology on the behavior of the main refractories that support BF operation and process, such as mud gun and runner’s refractories concrete, the present work was carried out. The study evaluates the behavior of a typical BF slag containing up to 5% Na2O in its chemical composition, representing a high level of briquettes in the BF ferrous burden mix. Firstly, a thermodynamic study was conducted to verify how this oxide could impact the corrosion ability of slag. Secondly, an experimental dynamic wear and corrosion study at lab scale was performed. The overall results showed that for different kinds of materials tested, both regular and high-performance refractories, the slags tested do not compromise their performance, providing important insights for BF operators.

Speakers: Mr Vinícius de Morais Oliveira (Vale S.A.), Mr Eric Sako (Shinagawa Refratários do Brasil)

Caster Design & Process Optimization

2.3.4

Convener: Marco Alloni (Prosimet S.p.A.)

228 Development of optimized continuous casting process for zero-defect round blooms production in high silicon 54SiCr6 automotive spring steel. Production trials in Acciaierie Bertoli Safau S.p.A.

Is well established that surface quality plays a significant role on the fatigue life of components. Therefore, the quality of the starting feedstock is mandatory for obtaining a wire rod suitable for the production of highly stressed elements, such as automotive suspension springs.

The paper describes the positive experience made by ABS (Acciaierie Bertoli Safau, Italy) during the development of a dedicated casting process of high silicon grade 54SiCr6 for automotive applications.

The development path is presented, with focus on the implemented aspects. The key factors that allowed a quality change are commented (i.e. materials, process parameters, automated mould flux feeder, Non-Destructive controls). The evolution of the learning process is fully described, showing for each modification effects and results obtained to achieve a zero-defect casted product. A special care to surface defects and to surface Carbon pickup will be described.

The satisfactory quality of the achieved product confirms the effectiveness of the optimization process.

Speaker: Sara Busolini (Acciaierie Bertoli Safau)

229 Development of an Optimized Strand-EMS for Improved Microstructure and Reduced Segregation in Continuous Casting

In recent years, there has been increasing interest in enhancing the efficiency and product quality of the continuous casting process in the steel industry. The formation of coarse columnar grains and macrosegregation during continuous casting negatively affects the mechanical and physical properties of the final product.Therefore, developing techniques to control the microstructure and maintain a uniform composition distribution is essential. In this study, Strand Electromagnetic Stirring (S-EMS) technology was applied to improve the solidification behavior and refine the microstructure in the continuous casting process. The results showed that increasing the S-EMS current enhanced the formation of equiaxed grains and reduced grain size. However, a tendency for increased local macrosegregation was also observed. As a result, this study identified the optimal S-EMS application conditions to maximize equiaxed grain formation and grain refinement while minimizing compositional segregation.

Speaker: Soonho Lee

230 Improved Internal Quality of High-Grade Steel Plate Using PosHARP Technology

The demand for high-quality steel production has increased due to changes in the plate product market, particularly in the wind power and shipbuilding sectors. This study focuses on improving the internal quality of high-grade steel plates using PosHARP technology.
In the wind power sector, the size of wind power generator blades is being increased to enhance power generation. This has led to a growing demand for substructures made of extremely thick plates exceeding 100mmt. To meet this demand, the study developed technology to secure the internal quality of wind structural steel.
The technology involved two main steps. Firstly, Strand EMS was used to apply electromagnetism, homogenizing the liquid and reducing the formation and segregation of 1/2mmt central equiaxed crystals. Secondly, after soft reduction, the reduction force was increased using PosHARP Segment to minimize segregation and porosity inside the slab.
The results of the study demonstrated that by using Gwangyang work's 300mmt slab and applying PosHARP and Strand EMS technology, the internal quality of extremely thick plates could be effectively secured. These results successfully met the customer's demand for internal quality.
In conclusion, the application of PosHARP technology has significantly contributed to improving the internal quality of high-grade steel plates. As the production rate of ultra-thick, high-grade steel increases, this technology will continue to play a crucial role in ensuring the competitiveness of continuous casting.

Speaker: Mr You Beom Cho (POSCO)

231 The new MSR bloom caster at Saarloha Advance Materials, Pune

Saarloha Advance Materials Pvt. Ltd. (SAMPL), a Kalyani Group Company, headquartered in Pune, India, is a leading steel manufacturer renowned for its high-quality alloy and special steel products. With state-of-the-art facilities and a focus on innovation, the group serves diverse sectors, including automotive and engineering. With the installation of the new 2 strands bloom caster, supplied by SMS Concast, SAMPL strengthens its position as leading supplier for high quality steel.
The caster – first of its kind in India – is equipped with six different section sizes, ranging from 160x160mm square billets to 340x400mm blooms and including a Ø500mm round section, and able to cast a wide range of steel grades, this 12m radius caster allows KSG to flexibly respond to any market request.
The machine is equipped with CONFLOW electromechanical stopper system, CONGAUGE steel level and Mold powder thickness measuring system, CONDRIVE Electromechanical Direct Oscillation Drives, CONSTIR Mold- and Final-EMS, air-mist secondary cooling, Level 2 with COOL Solidification model, Dynamic Mechanical Soft Reduction (DMSR) and rigid dummy bar to ensure quick re-stranding and high machine availability.
The 7 DMSR modules represent the main technological feature of this caster: each module can apply a force in excess of 2000kN, while the online solidification model COOL ensures that the optimal steel grade specific reduction pattern is dynamically applied and adapted to any change in casting conditions, ensuring always optimal efficiency and performance of the DMSR process.
The very limited installation space in the existing building represented another challenging aspect of this project requiring dedicated design solutions.
This paper will outline the main technological features in detail and present the quality results that have already been achieved in standard production after an intensive hot commissioning and testing period.

Speaker: Marco Abram (SMS group)

Energy Efficiency & Decarbonization

2.2.4

Convener: Prof. Klaus Krüger (Ingenieurbüro Klaus Krüger)

232 Simulating the use of renewable and alternative Carbon-bearing materials and hydrogen in the Electric Arc Furnace through a flowsheet model

The European steel sector is challenged by the ambitious objectives of the European Green Deal, which aims to schive climate neutrality by 2050. Therefore, novel C-lean and sustainable steelmaking processes are being investigated through large-scale pilot projects, accompanied by studies on the possibility to improve operating practices and introduce new components in conventional routes. As far as the electric steelmaking route is concerned, replacement of fossil carbon with renewable and/or alternative carbon sources, and use of green hydrogen for heating purposes in electric arc furnaces are being investigated. In particular, within the European project entitled “Gradual Integration of Renewable non-fossil energy sources and modular heating technologies in EAF for progressive CO2 decrease” (GreenHeatEAF – G.A. No. 101092328) a flowsheet model of the Electric Arc Furnace (EAF) process was updated to simulate the addition of biochar/biomass, plastic and tires in the EAF as well as the possibility of feeding the EAF burners with hydrogen or natural gas/hydrogen blends. Such model is being used in scenario analyses aimed at assessing the effects of using such C-bearing materials and/or hydrogen on both process performance and key product characteristics. Preliminary results highlight that no major negative effects on the product are observed from the use of alternative C-bearing material, independently on the way they are introduced in the furnace. However, real industrial trials show that an excessive amount of some of them can compromise operational safety and leads to poor slag foaming. On the other hand, the use of hydrogen in EAF burners leads to a consistent reduction in CO2 emissions, while affecting the moisture content in the off-gases and the hydrogen content in the molten steel.
The paper provides an overview of the model and presents the results of simulations that were carried out in the context of the GreenHeatEAF project.

Speaker: Prof. Valentina Colla (Scuola Superiore Sant'Anna)

233 Electrification of High Temperature Heating Demand: A Techno-Economic Perspective on Decarbonized Steel Making

The steel industry, known for its high carbon intensity, has primarily focused its decarbonization efforts in the ironmaking phase, which accounts for 70% of the sector's total emissions. However, the steelmaking and post-processing phases, responsible for the remaining emissions, have been largely overlooked until now. These phases contribute a significant percentage of emissions that must be addressed to achieve full decarbonization of the industry. This paper provides a comprehensive review of existing literature on steel industry decarbonization, followed by a comparative analysis of various electrification technologies and conventional methods, specifically targeting the mini-mill. The study evaluates the energy intensity and emissions reduction potential of electrification technologies such as hydrogen combustion and plasma heating torches. It also examines the effectiveness of these technologies for preheating scrap entering the electric arc furnace (EAF) and assesses the impact of different metal feeds (scrap, DRI, H2-DRI) on the EAF's energy balance. Additionally, the study investigates the potential of electrification technologies for the reheating furnace. Finally, the economic viability of electrifying mini-mill operations is evaluated, considering future trends like carbon pricing and energy costs. The findings suggest that electrification technologies present a viable strategy for decarbonizing the steel industry. However, their effectiveness is highly dependent on the emissions profile of the electricity used. Moreover, the economic viability of these technologies remains a significant challenge, highlighting the need for policy measures to support the transition towards a sustainable steel industry.

Speaker: Ana Oncina Mico (ABB)

234 Pneumatic injection of carbon neutral sources in the EAF melting process: a comprehensive overview of the use of new materials

The green steel revolution in the electric arc furnace route requires a reduction in the use of fossil coal and an increase in the use of carbon-neutral sources such as biochar, polymers, and rubber. The use of these new types of alternative materials, have highlighted several aspects that must be considered to obtain a reliable and effective use for the generation of foamy slag during the melting process.
The paper discusses advantages, disadvantages, limits, potentials and technical aspects to be considered for the effective and safe pneumatic injection of the new materials, such as physical characteristics, storage system, injection rate, injectors design and positioning. This work provides also examples of carbon neutral sources injection systems in some EAF plants around the world.

Speaker: Mr MASSIMO IACUZZI

Energy Efficiency & Recovery

5.3.4

Convener: Matteo Marten-Perolino (AIM)

235 REUSE OF RECOVERY THERMAL ENERGY FOR WATER TREATMENT IN STEEL INDUSTRY

Water consumption and wastewater disposal are critical challenges in the steel and metallurgical industries. Conventional reverse osmosis (RO) systems, widely used for producing demineralized water in cooling circuits, generate a concentrated waste stream (25-50% of feed water), which requires disposal due to high levels of calcium, magnesium and other contaminants.

At Contec Industry, we apply our WASM method, a sustainable approach aligned with ISO 14046 and ISO 14001 standards, to optimize water reuse and reduce environmental impact. Our solution integrates vacuum evaporation technology with waste heat recovery, converting excess thermal energy (hot water or steam) into a resource for water treatment. This enables the production of low-salinity distillate for reuse, minimizing fresh water intake and wastewater discharge.

The presentation will be accompanied by a real-world case study, demonstrating the practical application and benefits of this innovative solution in an industrial setting.

Key Benefits:

• Reduced Water Consumption: Maximizing reuse of treated water in cooling circuits and wastewater treatment plants (WWTP).
• Lower Wastewater Discharge: Decreasing the volume of reject water, reducing environmental burden.
• Enhanced Energy Efficiency: Utilizing available heat from industrial processes, lowering energy demand.
• Cost Savings: Cutting operational costs for osmotized water production.
• Sustainability & Compliance: Improving the water footprint of the facility and contributing to ESG performance.

This approach exemplifies how circular economy principles can drive efficiency in industrial water management. By transforming waste heat into an asset, steel plants can achieve significant environmental and economic benefits, aligning with global sustainability goals.

Speaker: Mr Angelo Ferranti (Contec Industry srl)

236 EAF Waste Heat Recovery: Turning Industrial Waste into Sustainable Energy

The project involved a revamping of the EAF furnace at the steelworks department, including the construction of a new primary flue gas circuit and the installation of a closed-loop system for heat recovery.
This recovered heat is transferred to the district heating network via 1.2 km of newly installed pipelines, connecting the steel plant to its central heating facility.
As a result, the system can efficiently channel the recovered heat into urban networks, delivering it sustainably as hot water to end users.
The recovery and utilization of heat generated by the steelworks actively contribute to decarbonization of district heating plant, achieving an annual reduction of 11,400 tons of CO₂ equivalent to the environmental benefit of planting approximately 230,000 trees.

Speakers: Mr Matteo Diani, Mr Philippe Brocard, Vincenzo Morreale

237 Waste Heat Recovery systems for EAF primary fumes

A key factor to pursue the “green steel” concept, is not only the emissions reduction and the lowering of the carbon footprint of the steel plants, but also the optimization of the energy consumption.
This optimization passes, of course, primarily through the direct reduction of the energy consumption, but can be pursued also through the recovery of waste energy. In steel making plants, the Electric Arc Furnace is a big source of waste energy that is basically the thermal energy contained in the primary fumes.
Part of this thermal energy can be recovered with dedicated Waste Heat Recovery Systems that are installed directly in the EAF primary fumes line.
Several configurations can be adopted and the main difference between the different technical solutions is the output of these systems: the focus of our study are the systems designed for saturated steam production and for electrical energy production.
Both systems base their operative principle on the transfer of heat to a cooling media that flows in two different parts of the primary fumes line: the radiative parts (the cooled parts) and the convective part (the heat exchanger).
Danieli Q-STEAM is the system that allows to produce saturated steam, that can be used for processes directly inside the plant or for users outside the plant.
Danieli CHR is instead the system that is specifically designed to recover the thermal energy and produce electrical energy with the use of ORC technology.
Both systems are designed to mitigate the discontinuous process of the furnace, thanks to their accumulation systems that allow to reduce the peaks and have a more continuous output downstream.
This study analyses both technical solutions proposed by Danieli, presenting some case study applications that allow also to better understand the amount of energy that can be recovered.

Speaker: Mr Alberto Feruglio (Danieli & C. Officine Meccaniche S.p.A.)

Roll Technology & Maintenance

3.1.2

Convener: Silvia Barella (Politecnico di Milano)

238 Wear and oxidation behavior of cast high-speed steels used for work rolls in hot rolling mills

Cast high-speed steel (HSS) work rolls are used in roughing and finishing stands of hot rolling mills, as they possess high hardness and wear resistance, which is responsible for their great durability in service. During the rolling process, depending on the operating conditions in the respective stand, the degradation of the work rolls is caused by a combination of thermal fatigue, rolling contact fatigue, adhesive wear, abrasive wear, and corrosion. Furthermore, wear-protective tribolayers may form because of the oxidation behavior, which significantly impacts the wear of the rolls.
A customized wear test rig was used to investigate the wear behavior of HSS under different hot rolling conditions. This test rig enables the simulation of rolling conditions between the work roll, the back-up roll, and the hot-rolled steel. The test parameters were systematically varied to ensure that the wear behavior was assessed under conditions similar to those experienced in the R2, F1, and F2 stands at Tata Steel's Direct Sheet Plant in the Netherlands. Additionally, high-temperature oxidation tests were carried out at different temperatures to investigate the oxidation behavior of HSS. The degradation mechanisms and the oxide formation were analyzed using light optical microscopy (LOM) and scanning electron microscopy (SEM).
The results of this study demonstrate the impact of parameters such as temperature, rotational speed, and slip on the wear and oxidation of specific HSS grades. Additionally, correlations between the carbide content, the carbide types and the wear behavior of HSS are highlighted. The experimental methods only enabled reproducing the surface degradation of the rolls after use at Tata Steel's Direct Sheet Plant to a limited extent. However, the combination of wear and oxidation tests helps explaining the wear and oxidation behavior of HSS rolls under industrial hot rolling conditions.

Speaker: Maximilian Reiter (Eisenwerk Sulzau-Werfen R. & E. Weinberger AG, Tenneck, Austria)

239 PERT GRINDING BALL ROLLING MILL

Nowadays grinding balls production process is mainly done by casting or by pressing, processes which involves anyway low productivity and poor quality on finished products.
PERT has developed a new revolutionary rolling mill to produce high quality grinding balls by rolling process, starting from a round bar coming from upstream bar mill rolling.
Round bars are heated up by a traditional gas/oil fired or by induction furnace and then rolled by means of a single stand which rolls the round bars into grinding balls of different sizes, ranging from diameters 20 mm up to 150 mm.
Rolls grooves design is the technological core of the process, in fact helicoidal groove has been designed for this particular application, guaranteeing a perfect ball shape and roundness.
Rolling line is composed by a discharging roller table, equipped with heat retaining covers, a set of pinch rolls which transfer the bar along the line, a set of fixed and rotating guides and a rotating pinch roll which push and rotate the bar before stand entering.
An inline heat treatment is foreseen to achieve the required surface and volumetric hardness, followed by an equalizing horizontal cooling bed and final balls storage and automatic packaging equipment.
Rolling process can guarantee a very high productivity rates, starting from 2 tph for smaller sizes up to more than 30 tph for bigger sizes.
Real cases of grinding balls rolling mills will be showed, mainly regarding plants supplied in India (Customer : JSW Steel) and Turkey (Customer : ETI BAKIR).

Speaker: Mr NICOLA TOMBA (PERT SRL)

240 Sustainable repairs of machine parts in rolling mills by advanced coating technologies

Machine parts, like chocks, rollers, HGC cylinders or gearbox housings, are the backbone of every rolling operation for section and flat rolling mills. They are essential for the delicate production process and ensure perfect product quality, tolerances and dimensions. However, rough operating conditions, such as elevated temperatures, corrosive media, high static/cyclic loads and abrasion, lead to significant wear during rolling or strip processing. Proper maintenance can prolong the service life, but these harsh conditions will lead to a decrease in product quality over time and ultimately, the failure of every component. The production process of new parts, especially for heavy machine parts like chocks, is often very energy intensive. Multiple tons of grey cast iron have to be molten, poured and fully machined. Additionally, the lead-time of single components or fully assemblies can be multiple months up to years. This is where repair solutions by coatings are a sustainable and economic alternative to the procurement of new parts. Worn out areas can be geometrically restored, functional areas can be restored and protected against abrasion and corrosion, hard chroming can be replaced by REACH compliant alternatives. Additionally, repair solutions by coatings offer a significant reduction in lead-time. This paper gives an overview of industry trends and recent developments within the SMS group, utilizing advanced coating technologies like High-Velocity Oxygen Fuel spraying (HVOF), High Velocity Air Fuel spraying (HVAF), Extreme High Speed Laser Application (EHLA), Laser Metal Deposition (LMD) and high speed Arc Wire Spraying (AWS) in combination with state of the art global machining capabilities.

Speaker: Mr Markus Mirz (SMS group)

241 Advanced manufacturing and improved performances of hot rolling mill edger rolls (EdgerRolls)

As the time between roll changes is continuously increasing due to improved performances of roughing rolls, a newer problem is that the performance of the edger roll becomes a bottleneck inducing strip defects crises and mill (unplanned) stoppages only to change the edger rolls. Additionally, worldwide the supply of edger rolls is becoming a problem. Especially for European hot strip mills this major concern becomes critical as only one roll supplier remains for the supply of small cast alloyed steel edger rolls. Moreover, the ecological footprint of traditional production, transport and usage of edger rolls is quite poor, as they are scrapped after just a few mill campaigns.
To tackle this situation a European funded project called EdgerRolls (RFCS-2023-02-PDP 101157368) has been launched in July 2024. The main objective of this project is to improve the performance of edger rolls through different approaches. A first one is the improvement of the cooling as well as testing the implementation of lubrication for the edgers. A second approach is an evaluation of the edger geometries through modelling. Finally, alternative manufacturing and repair methods adapted to edger rolls are also considered. To evaluate the impact of different applied changes, a monitoring procedure and tool will be developed as well as a roll profile measurement.
The project will also contribute to suppress edge slivers, one of the main uncontrolled defects in hot rolling. These defects occur with an increased wear of the edger rolls and limit campaign lengths. Edger roll wear and caliber condition are the main contributing factors to the severity of the defect.

Speaker: Mr Jurgen Malbrancke (CRM Group)

242 On The Performance of Implementing Pre-conditioned Oxide Film of HSS Rolls in A Hot Strip Mill

Hot strip mills require higher-quality, incident-free rolls to enhance productivity in the production of technical strips with stringent surface quality requirements. This necessitates rolling engineers to innovate new operational designs. The spin-cast HSS grade roll, engineered in Europe, stands as one of the most advanced grades developed over decades. Despite being a mature product, there is still room for improvement, particularly in terms of the roll surface condition, to meet the ever-growing demands of strip products.

Hot strip mill operations have effectively harnessed the natural formation of a thin oxide glaze on HSS rolls during the rolling process. Extensive research has been conducted to gain a comprehensive understanding of this phenomenon. It is crucial to establish this protective glaze in the early stages of each rolling campaign. Maintaining the oxide glaze for as long as possible is essential for producing strip products with high surface quality. However, the formation of this glaze requires a certain amount of time under hot rolling conditions, often resulting in the first few strips being rolled without a fully developed oxide glaze on the roll surface. Therefore, a pre-conditioned oxide film (POF) on the ground surface of HSS rolls is necessary to ensure the development of a well-formed oxide glaze under harsh rolling conditions.

This article describes the operation and implementation of a pre-conditioned oxide film on HSS rolls in a hot strip mill at Baosteel. The rolls are prepared in the roll shop after grinding and before usage. Following years of development, the POF rolls has been fully integrated into the mill's operations, enabling the production of high-quality strips while also achieving a cost saving of up to 50% for HSS rolls.

Speaker: ZHI ZHANG (BAOSHAN IRON&STEEL CO. LTD)

Special Applications & Performance

4.1.2

Convener: LUIGI CHINAGLIA (FOMAS S.p.a.)

243 Laser Cutting of Key Metals in the Construction Industry

This study examines the laser cutting applications of five key materials in the construction industry: High Strength Steel (HSS), Stainless Steel (StS), Weathering Steel (WS, also known as COR-TEN®), Reclaimed Steel (RS), and Aluminum. The analysis considers each material's unique characteristics, market trends, and the role of laser cutting in increasing sustainability and cost-effectiveness, while addressing both challenges and opportunities.
A combination of literature reviews, technical documents, market reports, and expert interviews was used to assess physical, mechanical, and economic factors, with particular attention to thick sections (10–40 mm) commonly used in construction. Forecasts tracking material use from the 2000s to the 2050s were developed based on the findings.
Results indicate a growing demand for HSS, driven by regulations and structural benefits. The cost-effectiveness of HSS is improved by laser cutting, which achieves tighter tolerances and simplifies welding processes, despite higher base prices of HSS. Stainless Steel is expected to grow in energy and hydrogen infrastructure due to its durability and low maintenance, although achieving high-quality cuts in thicker sections remains a challenge. Weathering Steel provides aesthetic and corrosion resistance benefits, although its protective patina affects laser-material interaction. Reclaimed Steel supports circular economy goals but faces challenges related to regulation, traceability, and surface quality; laser cutting and cleaning may help address these issues. The use of Aluminum is rising in sustainable and solar infrastructure, despite challenges from high reflectivity and thermal conductivity.
Overall, laser cutting enhances efficiency by reducing waste, energy use, and post processing. Material use trends forecast strong growth for HSS and moderate increases for StS, RS, WS, and Aluminum through the 2050s. Further research on optimized cutting parameters, particularly for thick profiles, is recommended to address the growing demand in sustainable construction and the evolving needs of the industry.

Speaker: Alper Kanyilmaz (Politecnico di Milano)

244 Steel metamaterials for EV battery box protection

Vehicle safety has improved spectacularly in recent decades with an estimated 25,000 fewer fatalities per year since the 1960s. At the same time, electrification has contributed to a significant increase in vehicle mass in the same period which partly negates any environmental benefit. Improved designs are essential to increase overall structural integrity and reduce weight, to meet future safety standards, extend vehicle range, and reduce manufacturing costs.

One such safety aspect is the protection of batteries during a side impact. In that case there is a severe risk of intrusion and damage to the cells, leading to potentially disastrous thermal run away and spread of fire. To this end we have investigated the potential of mechanical metamaterials with improved shock absorption capacity [1] to improve the resilience of the battery box to side impact. At the same time, by integrating the metamaterials into the chassis design we demonstrate the potential for manufacturers to reduce vehicle mass, thereby improving their energy efficiency, without compromising passenger safety.

We show how by using material plasticity in metamaterial design we can strategically control how metamaterials deform under impact. [2] The resulting metamaterials have a unique combination of strength and stiffness with high specific energy absorption capacity. Finally, we will show how these metamaterials can be shaped into many geometries and sizes; they can be made from a broad selection of materials (any materials that exhibit plasticity, such as polymers, metals or composites); and they can be produced through a wide range of manufacturing methods which leads to their potential for mass production via conventional metal forming processes.

[1] Liu, W. et al. Harnessing plasticity in sequential metamaterials for ideal shock absorption. Nature 634, 842–847 (2024)
[2] Liu, W., Ennis, B. and Coulais, C. Tuning the buckling sequences of metamaterials using plasticity. JMPS 196(50):106019 (2025)

Speaker: Dr Bernard Ennis (Tata Steel Netherlands Technology bv)

245 Performance of a HSLA steel produced via EAF and ESP® process route for the service in gaseous hydrogen

Acciaieria Arvedi, with its ISP® and ESP® plants, produces flat rolled carbon steels certified carbon neutral from EAF steelmaking and thin slab continuous casting with direct rolling starting from recycled materials. The steels are produced for many different end-uses including stamping and deep-drawing for the automotive industry, building and structural applications, pipes for water, energy and oil & gas sectors. To extend its product portfolio, the Arvedi Group has shown interest in the hydrogen pipeline sector. For this purpose, a HSLA steel of the X46 grade has been casted and hot rolled via EAF steelmaking and ESP® process route followed by tube forming, HFW welding and seam annealing at Arvedi Tubi Acciaio. The material has then been fully characterized to meet firstly the requirements of the API 5L PSL2 standard for the sour service in the oil & gas transportation sector and secondly according to the ASME B31.12 standard for the hydrogen piping and pipelines including Hydrogen Induced Cracking (HIC) tests and KIH tests in a hydrogen environment. In addition, Slow Strain Rate (SSR) tests in a 100% hydrogen atmosphere and 1000 hours as exposure time have also been performed. As a result of the experimental activities, it has been demonstrated that the X46 HFW pipe produced via EAF and ESP® process route is suitable for the service in gaseous hydrogen.

Speaker: Lorenzo Zanaboni (Acciaieria Arvedi S.p.A.)

Slag Optimization & Process Control

2.2.5

Convener: Prof. Klaus Krüger (Ingenieurbüro Klaus Krüger)

246 Advanced Dolime Injection Techniques for Enhanced EAF Steelmaking: Insights from a New Collaborative Trial by Lhoist and IntecoPTI

As the steel industry continues to pursue greener practices, the injection of fluxes from sidewall panels into Electric Arc Furnaces (EAFs) has become state-of-the-art in the United States. However, this method remains underutilized in Europe. To address this gap, Lhoist, a leading flux provider, and IntecoPTI, an EAF equipment manufacturer, have developed a portable injection system designed to enhance the accessibility of this technology in Europe.
This study focuses on the introduction of injected dolime, examining its impact on raw material consumption, energy efficiency, foaming behavior, refractory lifespan, and overall productivity. An trial will be conducted in collaboration with a major steelmaker, utilizing dolime as the injected flux.
The paper presents the unique features of the injection system, evaluates its economic benefits, and discusses the anticipated outcomes of the trial. The findings offer valuable insights into the feasibility and advantages of integrating this flux addition method into the electric arc process, contributing to the steelmaking industry’s ongoing efforts to adopt more sustainable and efficient practices.
Keywords: EAF, injection, dolime, foaming, CO2 reduction, trial

Speaker: Mr Camille Douce

247 Electrical conductivity modelling of molten slag based on viscosity data - A mechanistic approach

The majority of core pyrometallurgical processes rely on redox reactions, i.e. chemical reactions that involve electron transfer. Such reactions occur, for instance, when molten metals are reduced from their oxidic precursors or, in general, when elements transition between the metal and slag phases. To gain a comprehensive understanding of these processes and for exploring potential redesign options, it is essential to investigate conduction phenomena (both ionic and electronic) in slag melts, since electrical conduction offers valuable insights into slag composition and fundamental reaction mechanisms. Moreover, the understanding of the electrochemical properties of slags is imperative to ensure effective operation of any electrometallurgical process (EAF, Smelter, Molten Oxide Electrolysis, etc.).
In this study, the electrical conductivity of molten calcium silicate slags is investigated through the utilisation of a four-electrode setup, also referred to as extended Van der Pauw measurement configuration. This configuration involves measuring the complex impedance of a melt over a frequency range of 0.1 to 100 kHz at varying immersion depths. The electrical conductivity of molten slags of varying compositions is studied and temperature-dependent findings on conductivity and viscosity are correlated by the Arrhenius and the Vogel-Fulcher-Tammann approach. In addition to the semi-empirical correlation, a mechanistic model is employed, motivated by the diffusive transport analogy of momentum and mass. Thereby, ionic conduction in the molten slag is related to viscosity data. This approach considers electrical conductivity as a cumulated contribution of ion-specific mobility, charge and ion concentrations, providing a fundamental perspective on ionic transport in molten slags. Subsequently, the model calculations are compared with the measured electrical conductivity data.

Speaker: Ms Nina Schlemmer (K1-MET GmbH)

Water Management & Treatment

5.3.5

Convener: Matteo Marten-Perolino (AIM)

248 Dry granulation process and technology for LF slag treatment

The dry slag granulation process developed by Tenova represents a significant advancement in the valorization of Ladle Furnace (LF) slag, contributing to circular economy principles and sustainable steelmaking. Unlike traditional water-based cooling methods, which present environmental and operational challenges, Tenova's dry granulation technology employs a forced air stream to achieve ultra-rapid slag solidification. This process effectively prevents dust generation, reduces greenhouse gas emissions, and enables the recovery of both mineral and metallic fractions. The process, based on Tenova patent EP4100551A1, involves pouring molten LF slag into a controlled air stream, causing very fast cooling and solidification. The flexibility of the plant layout and operation allows to obtain granulated material with different granulometry and different fraction of crystalline and amorphous phases up to 100%. This opens the possibility different applications in construction and cement industries. Laboratory experiments and industrial pilot and demonstration trials at different steelworks demonstrated the system's efficiency, confirming the expected material granulometry and morphology. The tests validated the CFD simulations that provided crucial insights for scaling up the process to full industrial implementation.

Key benefits of Tenova’s dry granulation process include: (i) elimination of water usage and associated wastewater treatment, (ii) reduction of hazardous emissions, including sulfur compounds, (iii) improved handling of slag by converting it into a granular, reusable product, and (iv) enhanced resource efficiency through the recovery of residual metals.
Following the successful demonstration trials, feasibility studies and engineering designs have been developed for industrial deployment. This innovative approach offers a viable, sustainable alternative to conventional slag disposal, reinforcing steel industry's commitment to environmental responsibility and material circularity.
Tests of material with final users in the construction sector are on-going to define the more promising valorization paths, moreover the extension to EAF slag in under evaluation.

Speakers: Enzo Josef Chiarullo (Tenova SpA), Ms Simona Oliverio (Tenova SpA)

249 ZERO IMPACT FOR WATER RESOURCES FOR A STEEL INDUSTRY COMPLEX

A Middle East Customer Contracts PERTEco (PERT environmental department) for the supply of the new Water Treatment Plant (WTP) for his Steel Complex composed of 1,500,000 tons Meltshop and two 500,000 tpy Bar and Wire Rod Rolling Mills.

The Steel Complex is located in a desert region, with a very limited water availability. In the aim of the sustainability the new WTP is design on zero impact to the regional water sources.

A supplementary wastewater treatment plant will be installed to treat the municipality water coming from the nearest city in order preserve the groundwater reserves.

With reference to the WTP in service to the Steel Complex The solution adopted, in order to reduce the water consumption is to use of equipment with low or negligible water consumption (hybrid-cooling towers and dry coolers) -application of a dedicated plant for the treatment and recovery of the drains (drain recovery DR-WTP). This allowed to respect the limits imposed by the availability of water on site and to maintain a safety margin for a future planned upgrade of the plant. The solution finally results also economically interesting, especially thanks to the water chemical conditioning saving.

Speaker: MATTEO TOMBA (PERT SRL)

12:50 Lunch

Automation & Digitalization

3.1.3

Convener: alessandro ferraiuolo (Marcegaglia Ravenna)

250 SMART Grease selection for Roller Bearings of Continuous Casters and Rolling Mills to reduce maintenance cost and extend bearing life.

The most demanding operations in the steel industry in regard to bearing lubrication and lifetime of bearings are continuous caster strand guide rolls bearings and Hot Strip Mill Work Roll Bearings.
They are operating in wet and hot environments causing water spray off or water washout of lubricating greases resulting in ingress of aggressive mill water. This contaminants and water cause corrosion and increase wear within roller bearings up to fatal damage and collapse of the bearing. As a result, bearings fail premature causing downtime, additional maintenance and spare parts cost and loss of production. This paper describes test methods to determine the behaviour of lubricating greases in regard to water spray off behaviour and how to select greases that provide extra protection under these harsh conditions. Several Thickener systems have been analysed and results will be discussed in this paper.

Speaker: Mr Tim-Oliver Mattern (Carl Bechem GmbH)

251 Relaxation and creep in hot coiled steel strip

A hot rolled steel strip that seemingly comes out as flat after the final rolling pass might potentially end up with flatness issues after it has been coiled. It is not easily understood which mechanisms in the coiling process are causing flatness issues. It is known from a material perspective that a combination of high stresses and temperatures can cause stress relaxations and creep deformations when the time in this state is long enough. A hot coiled steel strip at 600°C with a mass of 27 tonnes will long time to cool down and it is uncertain whether stress recovery and creep behaviour have an impact on the final flatness. To investigate this, a three-dimensional thermo-mechanical finite element model with a creep material model is used to simulate the influence of creep deformations on final shape. It is, on one hand found that a relatively complex stress profiles are developed through the strip thickness when coiling, with compressive and tensile stresses beyond the yield stress, and that the tensile stresses recover unsymmetrically on one side of the strip midplane. On the other hand, is it also found that the creep deformations are only a fraction of the plastic deformations caused by the mechanical work during the coiling process. Hence, it is concluded that creep mechanisms play no, or possibly a marginal role in the shape of the final shape. Whereas stress relaxations result in a stress neutral profile in the coiled state, which may cause shape variation after uncoiling and post processing.

Speaker: Johan Lindwall (Swerim AB)

252 A significant example of successful revamping of a wire rod line for the production of special steels

What are the product characteristics that the special steels market currently demands?
Quality, quality and quality. In terms of dimensional tolerance, achievement of specific and consistent mechanical properties, very high surface and internal integrity of the finished product. To meet these characteristics Kardemir Çelik Sanayi, a leading Turkish special steel producer exporting to more than 110 countries, has chosen Danieli to revamp its existing wire rod line for specialty steel production.
In particular, was chosen to install Danieli's latest and most modern technologies, such as the high-speed shear to remove on line head and tail of the product and avoid the use of operators in finishing area, the water line for the application of the in line Thermomechanical process to increase the metallurgical quality of the rolled products, and the TMB (Twin Module Block) the sizing unit that allows to achieve unbeatable dimensional tolerances.
These equipment and processes have enabled the partner company to gain an even more prestigious place among the world's special steel producers.

Speaker: Maicol Cimolino

253 Finite Element modelling of skid marks on steel slabs in a walking beam reheating furnace

Walking beam furnaces are common for reheating of steel slabs to reach temperatures for hot rolling. Inside the furnace, the slabs are carried on water-cooled skids that support and move them through the furnace. The point contact between slab and skid results in undesired cold spots on the slabs, skid marks, which persist to hot rolling of plate/strip; leading to increased deformation resistance, adversely affecting rolling performance and product quality. Such cold spots are often not considered by process models used by the furnace control system as it requires the temperature of the slab to be modelled in 3D. Therefore, the goal in this study is to develop a fast, 3D model that can predict the temperature evolution/profile of the slab, including skid effects to enable on-line predictions of skid marks. The temperature and heat distribution of the slabs was modeled using finite elements analysis. Boundary conditions were used to include the effect of heat transfer from thermal radiation and convection, including the effect of view factors and shadowing from static and moving beams. The modeled temperatures were validated against empirical measurements from an industrial reheating furnace and compared to the simulation model STEELTEMP used by the furnace control system FOCS. The developed model showed a similar performance in predicting the overall slab temperature in production conditions as the model used in the current FOCS system, while also giving predictions on the skid marks. With the developed model, it becomes possible to simulate the effect of skid layouts, alternative process control and transfer the results to downstream simulation model of the hot rolling to evaluate the effect on the rolling forces and final product quality. This would enable process operators to better assess the reheating process and allow measures to be taken to improve final product quality.

Speaker: Dr Johan Lindwall (Swerim AB)

254 Construction of heat treatment analysis model considering transformation plasticity and accuracy verification

In manufacturing of steel products, demand for thermo-mechanical controlled processing (TMCP) is increasing steadily to satisfy various properties. However, defect of shape occurs when the temperature distribution of steel products becomes uneven during the cooling process. As a result, productivity and product yield are decreased. Predicting thermal deformation with high accuracy is essential for optimizing cooling condition and increasing productivity. But it is difficult to predict thermal deformation after cooling process because thermal deformation is complex phenomenon interacting between strain, heat transfer, phase transformation. Especially, transformation-induced plasticity is known to act an important role as it affects the final product quality such as shape and residual stresses. In past studies, there are some analysis cases considering transformation plasticity through single-phase transformation such as bainitic and martensitic transformation. On the other hand, there are few analyses considering transformation-induced plasticity through multi-phase transformation.
In this study, thermal deformation prediction model considering transformation-induced plasticity through multi-phase transformation was developed to predict thermal deformation with high accuracy. And analysis accuracy and validity were evaluated by comparing between experiment and simulated camber of SUS304 and S25C plate samples after spray cooling one-side of them.
It found that experiment and simulated camber without transformation-induced plasticity were difference. In contrast, they were in good agreement by considering transformation-induced plasticity. Newly established thermal deformation predict method contributes to a deeper understanding of TMCP.

Speaker: Takuya Fujisawa

255 Unbeatable product properties and performance of Danieli's K-Spooler

From the world's first in-line twistless bar winding machine in 2002 to the present, the key features in terms of maximum coiling speed, maximum coil size, and mechanical and metallurgical properties of the Danieli K-Spooler have improved tremendously.
Achievements have been made that were unexpected at the time. Maximum coiling speed of 40 m/s for 8 and 10 mm rebar, final coil size up to 8 tons, productivity of 200 tph with the installation of 4 spooler machines fed from a single rolling mill, in-line application of hardening and tempering, soft quenching and the patented martensitic-free processes.
Danieli, through continuous development and close cooperation with leading coil producers, has managed to achieve and maintain leadership on this product and process. The following article will present the main successes achieved and the important challenges still open for the near future.

Speaker: Dr Maicol Cimolino

Caster Design & Process Optimization

2.3.4

Convener: Silvia Barella (Politecnico di Milano)

256 CFD and FEM study on redesigning the mould geometry of the thin slab caster of Tata Steel in IJmuiden for enhanced casting performance

Thin slab casters around the world are increasingly turning to thicker moulds to achieve three main objectives: boosting throughput for higher production, eliminating the need for a funnel to accommodate the submerged entry nozzle (SEN) and thereby reducing the risk of longitudinal face cracks (LFC), and enhancing meniscus stability to reduce sliver defects.
In the current landscape, where most steelmakers are heavily investing in energy transition infrastructure, major revamps of operational equipment are limited. Therefore, this study conducted a feasibility assessment to explore potential changes to the caster that would require minimal modification while increasing the mould thickness, including the Liquid Core Reduction (LCR). Throughout the study, the EMBR, SEN, and funnel shape remained unchanged, although changing the mould geometry may enable or even require further changes.
The analysis utilized computational fluid dynamics (CFD) calculations to assess the impact of potential changes on the flow at the meniscus. Additionally, finite element method (FEM) calculations were employed to evaluate the ability of liquid core reduction to maintain consistent slab thickness without causing cracks.
The study concluded that an increase in mould thickness from 90 mm to 110 mm is feasible without requiring a major revamp of the caster. However, this adjustment alone would not completely eliminate the need for the funnel. CFD calculations indicated that while flow velocities at the meniscus would decrease, meniscus fluctuations would increase. FEM calculations revealed that the reduction would elevate the risk of cracking, but this risk could potentially be reduced through adjustments to the secondary cooling.
The findings suggest that an increase in mould thickness can be achieved without a major revamp, but it may not fully address all challenges. These results offer valuable insights and development efforts aimed at enhancing the stability and performance of the thin slab caster at Tata Steel in IJmuiden.

Speaker: Dr Stefan Senge

257 Enhancing the Quality of Continuously Cast Products: Optimized Caster Design and Process Tuning for High-Quality Blooms

Achieving the highest quality standards in steel casting is essential to maintain competitiveness in an increasingly demanding market. High-end steel grades require minimal inclusions, superior internal soundness and defect-free surfaces - goals that can only be achieved through meticulous design, advanced technologies and precise optimisation of operating practices.
This article undertakes a comprehensive examination of the impact of caster design and practices optimisation through three case studies: a caster for high-end wire and bar production, an upgraded caster with mechanical soft reduction, and a flexible combi-caster for billets, rounds, and heavy blooms equipped with M-EMS, F-EMS and soft reduction as well. The analysis highlights key technological advances, including a vertical bending design for improved cleanliness, and electromagnetic stirring and soft reduction techniques for improved internal quality.
Across these plants, the paper provides insights into the application and optimisation of electromagnetic stirring (M-EMS and F-EMS) and soft reduction, detailing the parameters used and the results achieved. It also provides a comparative analysis of the different cases, highlighting how design choices and process parameters influence the quality of the final product. By examining these case studies, this article reinforces the critical role of advanced design and process optimisation in maintaining a competitive edge in the steel industry.

Speaker: Mr Stefano Baf (INTECO melting & casting technologies GmbH, Austria)

258 A LOOK AT DANIELI DCM'S STRATEGIC PLANT UPGRADES ACROSS ITALY

Recent developments have highlighted the Danieli DCM’s capability to execute advanced caster upgrades with the aim of improving the production portfolio and/or extending the file of equipment. The focus has been on optimizing production processes and optimizing plant downtime. A key factor in achieving these goals have been the use of preassembly techniques, which improved on site activities and streamlined installation.
Equipment was preassembled and tested in a controlled environmental. As a global company, Danieli DCM can complete challenging projects while providing full support to customer from engineering through to erection and commissioning phase. This paper presents three representative cases of long product caster upgrade performed in Italy in the recent years.
1. Customer A (Italy).
2. Customer B (Italy).
3. Customer C (Italy).

All the caster upgrades were completed during planned shutdowns, demonstrating the effectives of preassembly in deliver quality results with controlled operational disruption.

Speaker: Mr Achille Trisciuzzi (Danieli & C. Officine Meccaniche S.p.A.)

259 Bow-Type Continuous Casting: A New Era in Ultra-Thick Slab and Heavy Plate Manufacturing

Continuous slab casting is the leading technology for steel production, but it has limitations for heavy plate production. To pass ultrasonic tests, a reduction ratio of 3 to 4 from slab to final thickness is required, which eliminates central porosity and segregation. Current thick slab casters operate at a maximum thickness of 400 mm, limiting final plate thickness to 100-130 mm.
Primetals Technologies has advanced thick-slab casting with machines capable of casting up to 460 mm thick slabs. To cast such thicknesses in a bow-type caster, several special solutions are needed. Optimized geometry in terms of radius and roll layout improves bulging behavior and slab quality. A continuous straightening process, combined with high-temperature casting, prevents cracking. Hard reduction in the horizontal area of the machine improves slab center quality by reducing porosity and segregation with a thickness reduction five times higher than conventional methods.
The Single Roll DynaGap (SRD) segment allows individual roll gap adjustments, enabling precise reduction at the end of solidification. This reduces center porosity and segregation, making it easier to pass ultrasonic tests and reducing the required mill reduction to less than 3. This new generation of bow-type continuous casting machines with increased thickness and hard reduction capabilities opens new opportunities in the heavy plate market previously inaccessible to continuous casters.

Speaker: Dr Kerstin Baumgartner

260 Conseal for slabs: Patented solution for optimizing start of cast

Conseal for slabs is an innovative technology developed by SMS group, piloted at TATA Ijmuiden, aimed at optimizing the startup process of continuous casting plants in the steel industry. This technology effectively addresses common startup issues, such as the elimination of cooling scrap and the quality defects caused by it, while minimizing the risk of startup breakouts—factors that contribute to production inefficiencies and increased costs.
The core innovation of Conseal lies in its ability to create a completely sealed mold at the start of the casting process. This is achieved by positioning the Conseal on top of the dummy bar head, functioning as a consumable starter piece. The Conseal body and its sealings ensure a homogeneous connection between the Conseal material and the surrounding mold. This connection is reinforced by integrated cooling elements, maintaining seal integrity under high temperatures.
One of the primary advantages of implementing Conseal is the standardization and reduction of preparation time. Designed for easy installation, Conseal reduces the interval between casts, thereby increasing production capacity by allocating more time to actual casting operations.
The adoption of Conseal can lead to significant cost savings. By minimizing defects, quality issues, and the likelihood of startup breakouts, steel producers can substantially reduce expenses associated with rework and scrap.
The Conseal for slabs offers a practical solution for enhancing the efficiency and reliability of the casting process. It stands as a valuable tool for steel manufacturers seeking to optimize operations and reduce costs.

Speaker: Mr Alexander Drüen (SMS group)

261 High Speed Billet Casting: Introduction of a new Billet CCM at Tosyalı Demir Çelik

In June 2024 the new high speed billet caster at Tosyalı Demir Çelik, Sariseki, Turkey was successfully put into operation.
Supplied by SMS Concast, this new continuous casting machine represents a significant advancement in casting technology, offering exceptional speed capabilities while maintaining product quality and versatility. This state-of-the-art system can achieve casting speeds of up to 6.0 meters per minute, resulting in a total production capacity of more than 3Mio. tons/year. The machine is designed with a 10.25-meter radius, comprises of 7 strands and produces square billets with 150-millimeter side lengths.
This machine demonstrates impressive versatility in its product range: it can cast a wide range of steel grades, from rebar to cold heading grades and spring steels. This diverse portfolio allows Tosyalı Demir Çelik to meet a wide array of market demands without compromising on productivity or quality.
To support this casting process, SMS Concast has implemented several cutting-edge technologies: the state-of-the-art CONFLOW electromechanical stopper mechanism ensures precise mold level control even at high speeds, while INVEX mold tubes have been specifically developed for both rebar and SBQ billet casting. Mold and Final CONSTIR electromagnetic stirrers ensure the internal quality of cast products. The CONDRIVE direct oscillation drive allows for precise oscillation control, which is critical for maintaining quality and casting stability at high casting speeds.
To ensure quality is maintained also at high casting speeds, the Level 2 system continuously tracks all relevant parameters and provides detailed casting reports for each billet or bloom, ensuring that the elevated productivity of this machine matches the required market demands.
This paper shall outline the main technological features in detail and reflect the quality results that could already be achieved in standard production after an intensive hot commissioning and testing period.

Speaker: Carlo Cascino (SMS group)

Direct Reduction & Alternative Ironmaking

5.2.3

262 The impact of DRI ratio and quality on EAF operational and metallurgical performances

In the pursuit of decarbonization, the steel industry is increasingly adopting Electric Arc Furnaces (EAFs) due to their lower carbon footprint and operational flexibility. EAFs can efficiently utilize diverse raw materials, such as scrap steel, pig iron, and Direct Reduced Iron (DRI), to adapt to fluctuating market conditions, resource availability, and product quality requirements.
As the share of EAFs in steel production grows and scrap availability will not cover the higher demand, the industry must address the dual challenge of production increase, maintaining this operational flexibility while ensuring the production of high-quality steel. Adapting the raw material charge mix without compromising on quality is critical, particularly as market demands evolve towards higher-grade steels with precise chemical compositions and reduced impurity levels.
The DRI quality can have a significant effect on EAF performances and is pivotal in meeting the right product quality, particularly in controlling nitrogen and residual elements like copper, tin, molybdenum, and nickel. Understanding the impact of raw material characteristics on EAF operations is crucial for optimizing the charge mix to achieve targeted steel quality at a minimal cost.
This study is focused on the EAF's capability to produce stringent grades. Advanced metallurgical models and operational experience are used to assess the impact of DRI ratio and quality on EAF performance, including energy consumption and product quality. Furthermore, some SMS group developments are presented, allowing to enhance EAF performances and optimize mixed scrap/DRI operation. The study concludes with a techno-economic analysis of CO2 emissions and operational expenditure (OPEX) impacts across various EAF scenarios.

Speaker: Ms Katia Papalia (SMS group)

263 ZHyRON project: Valorization of iron-rich & Zinc-containing steelmaking by-products via Hydrogen-based Reduction

Problem and significance
Existing valorization processes for the treatment of Fe-rich and Zn-containing steelmaking by-products or wastes need a source of heat and a reductant. In most cases a fossil fuel like coal, coke or natural gas is used. The large rate of fossil fuels/reductants needed make pyrometallurgical processes very intensive in terms of CO2 emissions. Following the aim of the European Green Deal to make Europe climate neutral by 2050, one of the routes proposed is to move from carbon-based processes to hydrogen-based applications. Accordingly, to make the steel industry more CO2 neutral and achieve the zero wastes goal, new circular economy solutions must be developed and validated before their industrial implementation.

Solution
To tackle these challenges in the recycling of key steelmaking by-products, while minimizing CO2 emissions, ZHyRON will develop an innovative valorization route using green H2 as reductant together with green electricity as energy source. Fe-rich Zn-containing by-products will undergo pyrometallurgical and hydrometallurgical treatment to separate Fe and Zn. Within ZHyRON, the iron oxides units will be recovered as direct reduced iron able to be consumed in electric arc furnaces while the zinc will be recovered as zinc oxide concentrate with enough purity to be externally valorized by a zinc smelting company and/or used for other applications. The process water will be treated by waste heat driven membrane distillation and reused for H2 production. The ZHyRON route will contribute to circular economy and industrial symbiosis for long-term goal towards zero-waste.
The proposed technologies will be developed and endorsed at lab pilot scale, and the obtained DRI products will be validated in the steelmaking value chain by small scale smelting trials to assess the impact in the EAF process. In the current work, an updated summary of the activities already carried out will be provided.

Speaker: Laurent FRAIKIN (CRM Group)

264 Techno-Economic Assessment of H₂-DRI and NG-DRI-CCS Processes for Low-Emission Iron Production

The transition of the iron and steel industry to low-emission systems is mandatory for meeting the global targets of greenhouse gas emission reduction. As the sector still heavily relies on fossil fuels, the shift is particularly challenging. Hydrogen-based direct reduced iron (H2-DRI) has gained increasing attention, and it is currently considered one of the most promising option for zero-emission iron production. Alternatively, natural gas-based DRI plants equipped with carbon capture and storage (NG-DRI-CCS) could play a relevant role, in presence of a CO2 infrastructure and/or in absence of substantial and low-cost availability of renewable energy sources (RES). This may be the case in Europe, where full-scale CCS projects are advancing in the cement, lime, petrochemical and waste-to-energy sectors, offering the opportunity of CCS clusters.

This work aims to provide a consistent techno-economic comparison of H₂-DRI and NG-DRI-CCS systems, by evaluating their material (feedstock, products and CO2), energy and economic balances. The two processes are simulated using Aspen Plus® for a representative plant size of 2 MtDRI/y, designing configurations that include electrification wherever possible to minimize residual emissions and improve efficiency. The integration with RES, electrolysis and storage units is investigated via mixed-integer linear programming (MILP) optimization, to properly account for the cost of renewable electricity in different locations. For the CO2 balances, the analysis considers direct and indirect contributions, adopting a life-cycle approach (e.g., solar panel manufacturing and natural gas supply chain leakages).

Preliminary calculations indicate a cost of CO2 avoidance of 50-100 €/tCO2 in case of NG-DRI-CCS, while values for H2-DRI results in 150-300 €/tCO2 with short-term technology costs and between 0 (i.e., cost parity) and 100 €/tCO2 with long-term cost projections. The outcomes of this study contribute to a deeper understanding of the feasibility of H₂-DRI and NG-DRI-CCS systems for different locations, and under different technology development scenarios.

Speaker: Ms Sara Guazzi (Department of Energy, Politecnico di Milano)

265 Comparison of direct reduction by CO gas and carbonaceous materials

Today, commercial direct reduction (DR) processes predominantly use natural gas for the reduction of iron ores and emits large amounts of CO2. One way to decrease the CO2 emissions is by using carbon-neutral reducing agents such as biocarbon. This study compares the direct reduction behavior of a magnetite ore concentrate by different reducing agents: pure CO gas, anthracite (a low-volatile coal), a combination of pure CO gas and anthracite, and hydrochar (a type of biocarbon). Ore concentrate was briquetted with or without carbon material addition. The briquettes were reduced in a thermogravimetric analysis (TGA) furnace non-isothermally up to 1000 °C under argon or CO atmosphere.
It was found that the reduction of ore concentrate briquette in pure CO (without carbon addition) initiated at the lowest temperature (~625 °C), followed by ore concentrate briquetted with pristine hydrochar (~730 °C). In contrast, the reduction of ore concentrate briquetted with anthracite did not initiate until 825 °C, regardless of the atmosphere used. Furthermore, it was found that the reduction rate of the ore was the most rapid when it was briquetted with hydrochar, followed by when it was reduced in pure CO atmosphere without carbon addition, and lastly when the ore was briquetted with anthracite. The utilization of CO gas in the case when the ore was briquetted with anthracite enhanced the later part of reduction process. Ore concentrate reduced completely to metallic iron after sufficiently long holding time (1-3 hours) except when it was mixed with anthracite and reduced in argon atmosphere. The result shows that choice of reducing agent significantly influenced the porosity and thus the diffusion rate of CO within the briquettes. Furthermore, it can be concluded that the addition of biocarbon to iron ore agglomerate facilitates a more efficient reduction process while reducing the fossil-CO2 emissions.

Speaker: Yu-Chiao Lu (KTH Royal Institute of Technology)

266 Flexible pathways for green iron production

Against the background of our industry’s decarbonization, iron production is as essential topic for the steel industry and the availability of raw materials (e.g. technological requirement for virgin iron units when producing certain steel grades and – lagging - scrap availability in emerging economies) are two main driving forces.

Traditional, carbon-intense production route can be substituted with cleaner pathways and hybrid plant configurations combining different production routes (DRI, EAF, BF and/or BOF) and different reduction agents/sources of energy represent the main challenge for owners and operators of existing large-scale steel plants.

This article presents technical as well as logistical challenges connected to these hybrid configurations as well as their benefits and bottlenecks with respect to operating cost and carbon footprint.

Speaker: Mr Edo Engel (Danieli Corus)

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267 Design of a sustainable iron ore smelting system using biochar-based direct reduction and CO₂ sequestration to lower steel’s carbon footprint in Marcegaglia site at Ravenna port

Steel production is a major contributor to global CO₂ emissions, primarily due to the reliance on coking coal in conventional iron ore reduction processes. This study proposes an innovative system for the direct reduction of iron ore through a smelting process utilizing biochar as a renewable reducing agent, coupled with efficient CO₂ capture to minimize the carbon footprint of steelmaking.
Biochar, produced via biomass pyrolysis, offers a carbon-neutral or even carbon-negative reduction pathway. In the proposed system, iron ore is smelted in a high-temperature reactor where biochar acts as both a reductant and a source of renewable carbon. The process leverages the high reactivity and low impurities of biochar to facilitate efficient iron oxide reduction while minimizing slag formation. The resulting CO₂ emissions are then captured using post-combustion sequestration techniques, such as amine scrubbing or mineral carbonation, ensuring near-zero emissions.
Preliminary assessments indicate that this approach could reduce CO₂ emissions by up to 80% compared to traditional blast furnace methods. Additionally, the integration of biochar—derived from agricultural or forestry waste—enhances circular economy principles by valorizing biomass residues. The reactor design, biochar properties, and CO₂ sequestration efficiency will be faced to enable the industrial scalability. This system presents a viable transitional pathway toward greener steel production, aligning with global decarbonization goals while maintaining cost-effectiveness and material performance.

Speakers: Prof. Carlo Mapelli (Dipartimento di Meccanica - Politecnico di Milano), Dr Gianluca Dall'Osto (Dipartimento di Meccanica - Politecnico di Milano)

Hydrogen-Based Reduction

1.4.3

268 Important aspects to optimise hydrogen enrichment in direct reduction

Hydrogen enriched direct reduction (DR) is a key decarbonisation technology. Natural gas driven DR is established in industry mostly outside Europe but there are no experiences with syngas of high H2 enrichment > 80%. H2-based reduction is endothermic and the influences on effective kinetics and DRI morphology are not known. Also, properties like local permeability and movement of pellets in the reactor are not known and issues like sticking cannot be excluded. These can significantly influence the temperature distribution and flow of solids and gas. No reliable prognosis is possible yet, in particular regarding local permeability, process stability and product quality of industrial size furnaces where there are higher mechanical loads on the particles and larger local process differences.
Many activities have been initiated for demonstration of H2-enriched DR but they will not close all of these knowledge gaps. This paper summarises the current state of work and results of the Horizon Europe project “MAXimise H2 enrichment in Direct Reduction shaft furnaces” (MaxH2DR) which provides missing data and knowledge of H2-enriched reduction processes and products and combines experimental results with models to a unique hybrid demonstrator.
A physical demonstrator shows the linked solid and gas flow in DR shaft furnaces and a world-first test rig determines pellet properties at industrial conditions. The results are combined with mathematical models including the key technology DEM-CFD to develop the MaxH2DR hybrid demonstrator which is able to investigate scale-up and to optimise DR furnace design and operation for H2-enriched reduction.
This solid foundation of process knowledge is exploited to investigate also the DR process integration into existing steel process chains. Simulation tools are combined into a toolkit that covers impacts on downstream processes and gas and energy cycles. Promising process chains will be achieved for different steps along the road to full decarbonisation.strong text

Speaker: Dr Thorsten Hauck (VDEh-Betriebsforschungsinstitut GmbH)

269 Experimental and model-based investigations on the influence of iron ore properties on hydrogen-based direct reduction kinetics.

The considerable reduction of CO2 emissions is one of the main challenges the steel industry is facing and the transition towards sustainable production routes is imminent. Especially H2-based direct reduction, which allows for up to 98 % emission reduction, is seeing a lot of attention [1]. Besides the availability of green H2, the supply with DR-grade iron ore pellets is a major potential bottleneck and might inhibit the transition to low-carbon steelmaking in future [2]. One possible approach is a flexible utilization of varying iron ore feedstocks. In this context, knowledge on direct reduction kinetics is of major importance for an efficient process as key operational parameters of an industrial direct reduction plant, e.g. temperature and residence time, can be adjusted to the applied feedstock.
However, most available literature is focused on the influence of gas phase parameters on direct reduction kinetics, while less attention is paid to solid phase properties. In addition, experimental investigations often only provide a limited number of reduction tests resulting in high statistical uncertainty. In this work both issues will be addressed with an extensive investigation of different industrial as well as purpose-built iron ore pellets. For manufacturing of the purpose-built pellets, process parameters were altered in order to achieve a defined variation of porosity, grain size and gangue content. To evaluate the influence of those solid phase parameters on direct reduction kinetics, a high number of reduction experiments were conducted in a set-up designed for time-efficient testing. In fact, the presented results are based on over 300 single pellet reduction experiments. Accompanying, a detailed evaluation of the experimental results was performed including a particle-scale modelling allowing for the determination of kinetic parameters.

[1] Müller et al., 2021, DOI: 10.1016/j.clet.2021.100158
[2] Agora Industry and Wuppertal Institute, 2023, 15 insights on the global steel transformation

Speaker: Michael Gallwitz

270 The Role of Pre-Oxidation Degree, Particle Size, and Ore Composition in Optimizing Hydrogen-Based Reduction Efficiency of Magnetite Ores

The transition to fossil-free iron production necessitates innovative approaches to direct reduction processes utilizing hydrogen as a sustainable reductant. This study investigates the impact of pre-oxidation on the hydrogen-based reduction kinetics of magnetite ores, a critical step toward optimizing the efficiency of hydrogen-driven direct reduced iron (DRI) production. Four distinct magnetite ores were sieved into different size fractions and subjected to controlled oxidation in air at 600°C, generating samples with low and high oxidation degrees. These pre-oxidized samples were subsequently reduced in a hydrogen atmosphere under isothermal conditions, with reduction efficiency monitored via thermogravimetric analysis (TGA). Primary findings reveal a strong correlation between oxidation degree and reduction kinetics, with highly oxidized samples exhibiting accelerated reduction rates compared to partially oxidized ones. Particle size and ore composition further influence reaction dynamics, highlighting the interaction between mineralogy, pretreatment, and reducibility. X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS) analyses reveal phase evolution, morphological changes, and elemental redistribution during oxidation and reduction. These results will clarify the mechanistic role of pre-oxidation in mitigating kinetic barriers and enhancing hydrogen utilization. This work advances the understanding of process-structure-property relationships in hydrogen-based DRI systems, providing actionable insights for achieving sustainable ironmaking technologies aligned with global decarbonization goals.

Speaker: Pritesh Garg (Luleå University of Technology)

271 HYBRIT PILOT PROJECT: NEW SPONGE IRON PRODUCT WITH UNIQUE PROPERTIES

The steel industry accounts for a large share of industrial carbon dioxide emissions equivalent to 7% of global emissions and at least 10% of Swedish emissions. Europe’s and Sweden’s national climate targets clearly show the way – a transition of the industry to reach net zero greenhouse gas emissions by 2045.

Currently, steelmaking in blast furnaces relies on fossil coal for energy and to reduce iron oxide to pure iron. This process is responsible for approximately 85-90% of total carbon emissions in ore-based steelmaking.
In the HYBRIT process, iron ore pellets are reduced to iron using hydrogen gas without fossil carbon. The resulting iron has a porous structure, known as sponge iron or direct reduced iron (DRI). Water is the residual product from this process.

Developing a competitive value chain from ore to steel has been a primary focus of HYBRIT's work. This has been achieved by consolidating and integrating results from various process steps. Analysis shows that carbon-free direct reduced iron is well suited for industrial applications.

Sponge iron pellets reduced with hydrogen have better transport, storage, and melting properties compared to those reduced with conventional natural gas-based processes. Low iron oxide content and 0% carbon provide the sponge iron with robust mechanical properties, making it resistant to mechanical pressure, abrasion, and drops. Therefore, losses during handling and transport are minimized.

Speaker: Johan Riesbeck

272 Study of the reduction of a hematite pellet by CO-H2 mixture gas

As the goal of achieving carbon neutrality by 2050 has emerged globally, great changes are being demanded in the iron and steel industry. Among these, the need for a direct reduction process of iron ore to reduce CO2 emissions is gaining attention. The reduction process using iron ore pellets and a shaft-type reactor has already reached the commercialization stage; however, little is known about the theoretical aspects of the reduction rate of iron ore. In particular, when hydrogen-containing gas is used as a reducing gas to lower CO2 emissions, significant changes in the reduction reaction mechanism and rate are expected.
In this study, experiments on the reduction of hematite ore pellets using a CO+H2 gas mixture were conducted to investigate the reduction behavior under varying reducing gas conditions. The reduction rate was determined using thermogravimetric analysis (TG), and exhaust gas analysis was performed to examine the reaction mechanism. The rate-determining step of the reduction reaction was identified using the reduction rate measurements over time, and the rate constant for the corresponding step was determined.

Speaker: youngjo kang (Dong-A University)

273 Hydrogen direct reduction of iron ores: effect of agglomeration

Hydrogen ironmaking is becoming increasingly important in the field of scientific and industrial research. In particular, direct reduction proves to be an extraordinarily effective system for reducing harmful emissions in the steel sector. Naturally, the efficiency of the entire process is strongly linked to the type of agglomeration of the ferrous minerals. This work is dedicated to the analysis of the direct reduction of pellets or briquettes in a reducing atmosphere containing hydrogen. Naturally, we demonstrate that depending on the porous structure of the agglomerated minerals, the reducibility and level of metallization change considerably. In addition, carburization levels also tend to change, for the same process condition, depending on the agglomeration state. Here we propose a numerical-experimental model developed through finite element calculations supported by a detailed kinetic analysis for the prediction of the best direct reducibility conditions.

Speaker: Prof. Pasquale Cavaliere (University of Oulu)

Slag Optimization & Process Control

2.2.5

Convener: Marco Knepper (Hüttenwerke Krupp Mannesmann GmbH)

274 Fast process slag analysis with laser spectroscopy, opening new opportunities for active optimization during melting and refining process.

The growing trend in today’s steel-making industry is enhancing scalability with the goal of net zero emission. This requires increased cost and process efficiency while reducing carbon emissions. To run a sustainable process, tighter control of process parameters along with close loop monitoring of liquid bath and slag plays an invaluable role. However, in terms of slag analysis, due to a relatively longer lead time ( transport + homogenization + XRF analysis ), the operator needs to wait at least 10 up to 20 minutes. As a result, decisions regarding basicity and flux addition have mostly been taken based on subjective evaluation of slag (from active heat) as well as historical slag data.

With Laser-induced breakdown spectroscopy (LIBS) reliable slag results can be delivered without complex homogenization. This allows the total measurement time to be reduced up to two minutes. Since slag results from each heat in EAF and LMF (before and after alloying) are available at the same time as melt data, decisions regarding process parameters optimization become more informed. This has the potential for increased refractory service life, production cost and raw material savings. In the oral presentation, data from LIBS-based sensors (operated in the pulpit) will be presented as well as process benefits from long-term operation will be shared.

Speaker: amit ahsan (SECOPTA analytics GmbH)

275 On the benefits of switching from lime to dololime fines injection in electric arc furnace

The successful implementation of switching from lime to dololime fines injection in an electric arc furnace owned by the company United Steel in Kuwait is here discussed from technical and economical points of view. This need arises from the generation of excessive dololime fines (particles less than 10 mm) and insufficient lime fines (particles between 5-15 mm) at the lime and dololime plant owned by the same company that supplies the raw materials to the steelmaking plant. This size disparity presents operational challenges within the steelmaking process, like the need to externally supply the deficit of lime fines meanwhile briquetting the dololime fines to reach lump-like size. Thus, an innovative strategy was implemented to overcome these issues and optimize material utilization. The solution involves replacing the whole lime fines injection with the available dololime fines injection while increasing the amount of lime lumps and consequently reducing the use of dololime lumps to keep the required mass balance in comparison to the original practice. Tests were carried out on 106 heats before (53 heats) and after (53 heats) the changes in the process and hypothesis testing was used to statistically evaluate the variation in flux, energy, oxygen and carbon consumptions. The implemented strategy results in several key improvements, namely a reduction of 3.2 kg/tsteel and 0.6 kg/tsteel of lime and dololime consumption, respectively, while keeping constat the other process parameters. The economic benefits are significant, too. By eliminating the need for external briquetting of dololime fines and reducing purchased lime fines quantities, the solution generates annual cost savings of approximately USD 350,000.

Speaker: Prof. Davide Mombelli (Politecnico di Milano - Dipartimento di Meccanica)

276 New techniques for improvement of the monitoring and conditioning of slag in EAF steelmaking for the optimization of steel treatment and slag recovery

In the modern steel production it is important to have an integrated view of the production processes and plants including performances optimization, maintenance conditions, and reduction of environmental impacts through reduction of residual wastes and CO2 emissions from the production.
In particular to consider the slags coming from the production processed of EAF and LF is a relevant point including both evaluations regarding the process treatments optimization and the conditions of residual slags from production as necessary to increase capability of slags recovery.
In fact the proper slags conditions both in EAF and in LF are crucial to increase the efficiency of the metallurgical processes as dephosphorization, De-sulphurisation, Decarburization, deoxidation, slag foaming and refractories erosion.
For this reason to know the present status of the slags during the process and to define the proper target as slag conditions to be adopted during the treatments is a relevant point to manage and to improve the production processes and make more efficient the metallurgical processes.
In parallel to know the necessary target of the slags to be adopted for subsequent landfill or better for the slags reuse and recovery is also fundamental.
For this reason the slag conditioning and the process management to obtain the proper slag conditions is a point affecting both the circularity of the sector but also to improve the processes performances.
Acciaierie di Calvisano for this reason has developed the project islag, co funded by Research Fund For Coal And Steel) with the scope both to improve capability of process monitoring but also to develop the necessary Decision Support System to manage the slags In proper way as based on the previous concept of process management in particular including new sensors and also process modelling.

Speaker: Piero Frittella (FERALPI SIDERURGICA)

277 A Sustainable EAF Slag Practice Based on HYBRIT Laboratory Studies

Hybrit Development AB, a joint initiative between the mining company LKAB, steel producer SSAB, and electricity producer Vattenfall, aims to develop the world's first fossil-free ore-based steelmaking route. Since 2020, Hybrit has funded laboratory studies conducted by Swerim AB, the Swedish metallurgical research institute, to study the value chain from hydrogen reduction of iron ore pellets, to melting and refining of the hydrogen reduced iron (H-DRI).
This presentation will link and discuss the different parts of the study that covers sustainable EAF slag practice based on Hybrit’s H-DRI. This contains three parts: (1) the autogenous slag of H-DRI, (2) phosphorus refining, and (3) recirculation of slag.
H-DRI contains iron, unreduced iron oxide, and some other oxides. The pellet also contains impurities, mainly phosphorus. During the heating of H-DRI, the oxides melt prior to the iron and form an autogenous slag flowing in the H-DRI porous network. When iron melts, the slag is distributed as droplets in the molten iron, generating a huge surface area between metal and slag. This is very beneficial for the kinetics of reaction between the phases and to transfer all phosphorus to the slag. A possibility arises to use this opportunity to design the autogenous slag already during pelletization, to obtain phosphorus refining already during the melting of H-DRI. This would minimize the need for slag additions during EAF practice, shorten EAF process times and decrease the need for electrical energy.
Lastly, used EAF slag needs to be handled after the EAF process. The slag is not suitable for cement industry due to high iron oxide and phosphorus levels, and landfilling is becoming more and more constrained. Reducing iron oxide and phosphorus from the slag is therefore interesting. Then, it could partly be recirculated back to the EAF-process, and be more suitable for the cement industry.

Speaker: Dr Johan Martinsson (Swerim AB)

278 Slag changes in future steelmaking scenarios: simulation investigations

Achieving the climate neutrality by 2050 is the main goal of the European Green Deal, which fosters decarbonization of CO2-intensive industries, including steelworks. Deep transformations are ongoing to improve sustainability of steel production. Moreover, emerging markets and countries significantly affect availability and quality of raw materials. Therefore, steelmaking process changes and implementation of breakthrough technologies must face also this challenge: C-lean and green steel must be produced also in case of high-quality material shortage. Indeed, steel quality must be ensured also when introducing novel technologies, modifying well-known process conditions, or intensifying the implementation of circular economy concepts connected to by-products such as slag. In particular, knowing in advance the effects on slags of the transition toward C-lean steel production processes is fundamental to ensure valorisation of future slags in the overall value chain. The European project entitled “Investigations of Slags from Next Generation Steel Making Processes” (ref. InSGeP – G.A. 101112665) that is co-funded by the Research Fund for Coal and Steel addresses this topic. Among the different activities, an electric arc furnace flowsheet model has been adapted and is being used for simulations on the effects of charging different amounts and qualities of Direct Reduced Iron and Hot Briquetted Iron in electric arc furnace on slags as well as on the main aspects of product and process. Process modifications are also under investigations to compensate undesired variations (e.g. in terms of basicity index of slags). In addition, a smelter flowsheet model is under development to carry out investigations on slags obtained from this process. The present contribution focuses on the results of these simulations.

Speaker: Dr Ismael Matino (Scuola Superiore Sant'Anna - TeCIP Institute - ICT-COISP)

279 Slag foaming due to CO generated at the slag/metal interface

Slag foaming is a very important phenomena in the operation of the Electric Arc Furnace due to multiple benefits. It has been extensively investigated from an academic view point, however there are still many unresolved issues dealing with the real conditions that promote these phenomena. I many of the previous investigations the gas is artificially injected, rather than created at the interior of the slag or metal phases. The CO bubbles, which are responsible of the foaming phenomena can be created both in the slag due to FeO being reduced by injected carbon particles or by reactions at the slag/metal interface. This work reports an experimental work focuses on slag foaming due to CO produced at the slag/metal interface, with variations on FeO and basicity.

Speaker: Alberto Conejo (USTB)

Special Applications & Performance

4.1.2

Convener: Andrea Di Schino (University of Perugia)

280 Hydrogen Embrittlement in Pipeline and Cast Steels for Gas Transport Infrastructure

Using hydrogen/natural gas mixtures or pure hydrogen instead of natural gas is a key approach to industrial decarbonization, reducing greenhouse gas emissions and fossil fuel consumption. Given the extensive gas network, these mixtures are expected to be transported using existing infrastructure.
Natural gas pipelines consist of various components, including pipes, valves, and flange joints. Pipes are typically made of API 5L steels, which are formed during manufacturing, whereas gate valve bodies are made from cast structural steels. These materials have different microstructures, affecting their resistance to hydrogen embrittlement (HE). Cast steels contain micropores and defects that trap hydrogen and increase HE risk.
Two steels were selected for testing: X52, used for pipeline pipes in a formed state, and 1.0619+N, a cast steel used for gate valves. Both were subjected to electrolytic hydrogen charging in sulfuric acid electrolyte with CH₄N₂S as a hydrogen poison. Hydrogenation lasted up to 48 hours, followed by notch impact testing and hydrogen content analysis.
Initial hydrogen content ranged from 1.14 to 1.42 ppm. For 1.0619+N steel, impact energy decreased from 65 J to 50 J, while hydrogen content increased to 12.81 ppm after 24 hours. Fractographic analysis of fracture surfaces provided insights into failure mechanisms in different structural states.

Speaker: Dr Hana Jirkova (Research and Testing Institute Pilsen)

281 Effects on steel oxidation kinetics and oxide scale features of hydrogen combustion

The hydrogen combustion in reheating and heat treatment furnaces produces a new furnace atmosphere without or with lower concentration of CO2 and consequently higher H2O concentration. The higher water vapour content can change steel’s oxidation kinetic, as well as the oxide scale morphology and the oxide-steel interface features thus affecting the scale adhesion. The oxidation kinetics and scale features of different steel grades were studied by TGA (Thermo Gravimetric Analysis) at 1200°C, 1050°C and 900°C in atmospheres simulating working conditions of the burner with 100% NG combustion or 100%H2 combustion, followed by scale characterization by SEM with EDS analysis. Tests are carried out on large variety of steel grades (carbon steels and stainless steels) to evaluate also the effect of steel chemistry. Results show increase in oxide scale growth especially for the higher temperature range; differences among the steel grades according to the presence of some alloying elements have been also outlined. In some cases, the interface between scale and steel appears influenced by the higher presence of H2O in the furnace atmosphere.

Speaker: Mrs Nicoletta Zacchetti (Rina Consulting Centro Sviluppo Materiali)

Water Management & Treatment

5.3.5

Convener: Prof. Valentina Colla (Scuola Superiore Sant'Anna)

282 FerSol, the new three-in-one water treatment chemical

In many wastewater and process-water systems water chemicals are used to control the water quality. Typically a mix of pH control chemicals, herbicides, inhibitors, coagulants and oxidizing agents are used. A newly developed chemical called FerSol, which contains Ferrate (VI), combines several functions as it acts as oxidizing agent, coagulant and, as a side effect, it eliminates certain bacteria, fungi and viruses. These properties of Ferrate were known; the only problem was that the chemical was unstable and would break down in minutes. Ferr-Tech, the company behind Fersol, has solved the stability problem of the Ferrate (VI) and now this product is available for the market.

The benefits are clear; the product is environmentally- and human friendly, the residue of the chemical is Fe(OH)3, a harmless coagulant, and, due to it very strong oxidizing capacities, (stronger than ozone) it also eliminates biological growth.

Danieli Corus and FerrTech joint forces to introduce this product into the Iron- and Steel Industry (waste) water processing. In this paper the use and benefits of FerSol in the Iron- and Steel Industry is provided.

Speaker: Mr Peter Klut (Danieli Corus)

Potential Applications of Ferrate (VI) Solution in the Steel Industry.docx

283 Smart Automation for Efficient Water Management in Steelmaking: The Q-WATER System

Advanced automation is essential for ensuring precise control of cooling water flows at the right pressure and temperature, aligning with the real-time demands of industrial processes. This optimization maximizes energy savings while minimizing water consumption, forming the foundation of sustainable and efficient metal production.
The Q-WATER system is a cutting-edge technological package designed for comprehensive water management. It precisely matches the water supply from the water treatment plant (WTP) to the specific needs of each technological user during production. A key feature of Q-WATER is its integrated real-time monitoring, which includes process analytics, key performance indicators (KPIs), and detailed reporting on energy, power, and water consumption. This ensures enhanced efficiency and resource optimization across operations.
This paper presents the implementation of the Q-WATER system in industrial plants, highlighting its performance, achievements, and the benefits realized since installation.

Speaker: Mr Marcellino Fornasier (Danieli & C. Officine Meccaniche S.p.A.)

284 Ensured fresh water supply by waste and process water treatment

A sufficient water supply forms the base for a continuous production in iron and steel industry. Due to climate change, limitations of water outtake occurred during summer periods as well as changes of the freshwater composition to higher salt contents increasing the corrosion potential. Beside this, EU water directive, national framework and EU goals as “Zero Waste” or Zero Discharge” lead to an increased demand for closing of water circuits as far as possible and limitations in discharge. Further on, due to transformation of the steel industry to green steel, an increase of the freshwater demand is expected for increased cooling water demands at the direct reduction process as well as for the production of hydrogen. This requires the use of alternative water resources as organic loaded waste waters or process waters with high potentials of scaling due to the presence of fluoride and calcium. Main obstacles for reuse are beside the complex and strongly varying composition, the handling of the concentrates of the desalting processes.
For this purpose, suitable technologies and its combinations have been investigated and successfully demonstrated in field trials under operational conditions, e.g. at different streams of an integrated steel work or tin plant production. Exemplary streams were e.g. discharge gas washing water, blow down continuous casting or organic and solid loaded effluents from chemical-physical treatment plants. The investigated approaches consisted of a reliable removal of solids by ceramic flat sheet filtration, as mandatory step before any kind of desalting, desalting and softening by membrane-based capacitive deionization and a fraction in mono- and bivalent concentrates by selective nanofiltration. Depending on the case, water recovery rates up to 79% have been achieved by energy demands below 0.5 kwh/m³. Further on, a biocide based on sodium hypochlorite have been produced, by electrochemical treatment of the monovalent concentrate.

Speaker: Martin Hubrich (VDEh-Betriebsforschungsinstitut GmbH)

Advanced High-Strength Steels (AHSS) & High-Strength Steels (HSS) Development

4.1.3

Convener: Andrea Di Schino (University of Perugia)

285 Advances in Steels for Stronger Body-in-White and Enhanced Safety

Advances in Steels for Stronger Body in White and Enhanced Safety
Anthony J DeArdo
University of Pittsburgh

ABSTRACT
Over the past quarter century, the crashworthiness of production automobiles has improved significantly. sa Much of this improvement is the result of application of ultra-high strength steels in the safety cage or Body in White. Since the majority of steel mass resides in the BIW, mass reduction programs have largely focused on the BIW in programs to reduce the mass of automobiles. The development of, for example, 22MNB5, a high strength martensitic steel capable of being produced in very thin gauges, has been instrumental in this development of successful mass reduction programs.
Not surprisingly, the static tensile properties of the steel have been shown to be
related firstly to the processing sequence it has experienced prior to annealing,
and, secondly, to the annealing conditions employed. These combined phenomena
have been carefully studied at Pitt as a prelude to conventional continuous
annealing on Continuous Galvanizing Line Simulations. Although this original
work was performed to explain the sheared edge behavior of the steels in HER
tests, the marked influence on bulk properties could not be overlooked.

The bulk of this paper will focus on the properties of 22MNB5-type steels after
conventional hardening treatments including cold mill processing,
but will also discuss certain limitations caused by using these steels. One
prominent problem is Hydrogen Embrittlement which might be more prevalent
than first thought with the cathodic electrochemical reactions occurring during
priming and other coating processing. A second issue is the potential crack
nucleating features by cold hole punching introduced in the thin, long rail-like
geometries found in modern BIW. These and others will be discussed in this
presentation and publication.

Speaker: Anthony Deardo (University of Pittsburgh)

286 On the influence of EAF based steelmaking on AHSS

Nowadays the use of scrap-based Electric Arc Furnace (EAF) steels is a reasonable solution to reduce CO2 emissions, as the availability of steel scrap is expected to increase in the next 10-20 years. However, CO2 reduced steel produced with an EAF contains a higher amount of tramp elements such as copper and nickel compared to material from primary steel making. As one task in the material evaluation process it is necessary to assess the influence of these tramp elements on formability and to evaluate if these materials behave differently in classical sheet metal forming processes.
This contribution is based on the comparison of a hot-dip galvanized dual-phase steel DP800 and electrogalvanized martensitic steel MS1500 from primary steel making and secondary steel making with 100 % scrap content. Specially, a dual-phase steel with increased copper content and a martensitic steel with increased nickel content are evaluated. This study aims to identify significant differences in the microstructural and mechanical behaviour of these two steel grades depending on the production route and tramp element content.

Speaker: Jonny Bernhardt (Mercedes-Benz AG)

287 Development of High-Strength Dual Phase (DP) Steels with Enhanced Ductility

Dual phase (DP) steels, consisting of a soft ferrite matrix and hard martensite phases, offer a desirable combination of high strength and good ductility. Typically, an increase in martensite phase-fraction leads to higher strength but reduced ductility. However, in this study, an opposite trend was observed, where the ductility improved despite an increase in martensite content. This study focuses on understanding this unexpected behavior and aims to establish the microstructure design principles as a fundamental study for developing high-strength DP steels without compromising ductility. A detailed analysis of tensile deformation behavior from a microstructural perspective, combined with an evaluation of mechanical properties based on chemical composition and crystallographic characteristics, was conducted to elucidate the underlying mechanisms. The findings revealed that continuous increase in strength with increasing martensite content is not always achievable. In particular, DP steels in this study exhibited decreased yield strength and enhanced ductility even with increasing the martensite fraction. This behavior appears to be influenced by the morphological characteristics of martensite, especially the differences between intragranular lath martensite and intergranular globular martensite. In addition, the effect of globular martensite formed at grain boundaries on the deformation behavior remains ambiguous, whether it is beneficial, detrimental, or neutral for the improvement of combined strength and ductility. It implies the need for a more nuanced approach to analyzing tensile deformation in DP steels based on martensite morphology and alloy composition. Thus, this study underscores the importance of microstructural control in optimizing the strength-ductility balance of DP steels. The presentation will discuss these findings and propose a microstructural design strategy for achieving enhanced ductility alongside high strength in DP steels.

Speaker: Dr SEONGTAK OH (Hyundai Steel R&D Center)

288 Continuous Annealing and Galvanizing Line electrification: decarbonation as a new opportunity to produce HSS and AHSS by flash annealing

new production routes. Different scenarios for the substitution of gas-fired furnace with electrical powered solutions can be considered. In particular, flash annealing – so far only considered at laboratory scale – can be introduced at industrial level providing substantial benefits in terms of productivity and material properties.
The beneficial effect of flash annealing on the material properties - either conventional or advanced high strength steel grades - have been documented in the past decades based mainly on laboratory experiments. New mechanical and ductility / forming compromises can be achieved thanks to flash annealing, while limiting the alloying content. Some metallurgical uncertainties remain, mainly related to phased distribution and homogeneities.
Induction and quenching technologies are now mature enough to consider flash annealing and galvanizing at industrial scale:
- Induction technologies (transverse and longitudinal flux) allow rapid heating (~500°C/s.mm) over a large temperature range as requested for the processing of multiphase material containing retained austenite. Moreover, they allow efficient strip re-heating in the case of complex annealing cycles such as for example Q&P concepts.

• Dry-H2 fast cooling and Wet quenching cooling (up to -1000°C/s.mm) enable metallurgical control of all required phases as well as management of full requested product dimensional ranges and similar annealing cycle for single alloy chemical concept whatever the strip thickness.
  The presentation will review different CAL-CGL electrification scenarios depending on energy prices and product mix. In particular, the metallurgical benefits of flash annealing on flat-C steels and the related key technologies enabling such cycles at industrial scale will be evaluated and considered.

Speaker: Dr David Barbier (Fives KEODS)

AI & Machine Learning Applications

6.1.1

Convener: Prof. Valentina Colla (Scuola Superiore Sant'Anna)

289 From Data to benefit - application of AI technologies in steel production

In the ongoing digital transformation of the steel industry, Artificial Intelligence is more and more
integrated into the automation of the production processes. However, the true potential of AI
technologies can only be realized if preconditions to data quality are given, and domain expertise is
effectively digitized.
This presentation explores the application of AI technologies—such as machine learning, deep
learning, and expert systems—in areas like predictive maintenance, process control, and defect
detection. A special focus is placed on the unique characteristics of steel production data, including its
complexity, heterogeneity, and real-time processing requirements. Additionally, we discuss the
importance of capturing and structuring expert knowledge in digital form to enhance AI-driven
decision-making and ensure long-term knowledge retention. By combining high-quality data with
digitized know-how, steel manufacturers can achieve tangible benefits such as reduced downtime,
improved product quality, enhanced sustainability, and continuous improvement of the production
processes along the entire production chain. This paper will highlight best practices for transforming
raw data and human expertise into actionable insights, demonstrating how AI can drive measurable
benefits in steel production automation.

Speaker: Kurt Herzog (Primetals Technologies Austria)

290 Predictive-Prescriptive Quality Control in the Steel Industry: A Synergy of Human Knowledge, Machine Learning and Auto-mation Framework

Quality Control is an established process for all metals manufacturers. However, identifying a critical quality deviation at the finished product stage can be cost-intensive. Not only is the original order affected by delays due to late deallocation, but the reallocation of a finished product to a prime order becomes improbable, leading to a greater financial loss. Predictive-Prescriptive Quality Control aims to minimize finished product downgrades through a two-step strategy: first, by anticipating downgrade risk at the earliest possible stage; and second, by offering the best solution to mitigate this risk during subsequent production steps or by suggesting early deallocation. To achieve this goal, predictive models of finished product characteristics are systematically integrated into quality control operations at every suitable production step. These models use upstream data collected throughout the material's history, as well as downstream production instructions and expected process results, requiring comprehensive knowledge of the entire production route. The prescriptive model "inverts" the prediction by suggesting downstream changes to the material-specific production instructions to meet the target at risk. Such precise models are assumed to be not just business-specific but even plant-specific. Therefore, a synergy of metallurgical knowledge and machine learning methods (relying on plant-specific historical data) looks promising for delivering useful models. To operate such Predictive-Prescriptive Quality Control in an industrial environment, a stable Quality Management framework is required to orchestrate each model and quality operation and ensure synchronization with the MES—a pivotal task that should not be underestimated for achieving the goal in day-to-day operations. By gradually integrating Predictive-Prescriptive Quality Control into Quality Management, the potential of collected process data can be harnessed to systematically reduce deviations and downgrades.

Speaker: Dr Alessandro Stenico (PSI Software SE)

291 Exploring capabilities of an auction-based multiagent system in real-time reactive scheduling

In this paper a distributed auction system intended to provide efficient real-time reactive scheduling for flat steel industry is introduced. We focus on the context of parallel finishing lines where several equipment units can be used to process the materials. When a severe disruption takes place, it is necessary to provide a feasible reschedule in a timely manner.
Regarding the scheduling algorithm, both materials to be processed and processing equipment units are conceptualized as agents that participate in auctions. Equipment units offer their availability, and each material bids to be assigned and sequenced to one of the corresponding allowed equipment. This approach enables implementing not only customer order-based material rules but also rules guiding the behavior of the material processing equipment units. Thus, through a series of bidding rounds the set of materials waiting to be processed are rescheduled with a multi-objective perspective.
From the information technology viewpoint, the critical timing efficiency requirement is handled by setting a distributed environment and using Apache Kafka messaging. The latter technology shows its efficiency in handling the information exchange required for the creation of auctions alongside the interaction of all the agents participating in each auction until the scheduling process is completed.
Finally, different configurations of the system are explored through a series of data settings. The estimation of the system performance when facing actual industrial setting cases is shown. Besides, the analyses of the solutions yield the identification of needs for additional rules as well as further functionalities.
Keywords: agent-based scheduling, rescheduling, flat steel parallel lines

Speaker: Miguel Gutierrez (Universidad Politécnica de Madrid)

16:00 Coffee break

AI & Machine Learning Applications

6.1.1

292 AI-Powered Classification and Prediction of Process Defaults in Steel Manufacturing

To improve operational efficiency and minimize downtime, it is crucial to understand the causes leading to process defaults in the steelmaking industry. This study presents a generalized framework applicable across a wide range of metal-forming processes, which is based on an AI-powered solution designed to predict and classify breakages caused by process anomalies. The proposed solution identifies the operational phase in which failures occur as well as the key process variables (such as motor current and rolling force) that may act as breakage precursors. The objective is twofold: on one hand, to distinguish breakages attributable to process anomalies from those caused by material defects; on the other hand, to extract insights and meaningful interpretations of the mechanisms leading to plastic instability. A predictive model leveraging historical data from IoT devices is combined with statistical modelling to detect early warning signals associated with breakages. This integration of techniques allows proactive decision-making and adaptive process control. The study adopts a high-performing architecture that utilizes integrated services to process and analyze large-scale data streams in real time. This scalable infrastructure ensures efficient data handling and facilitates predictive analytics, ultimately enhancing process reliability. A practical application in the cold rolling scenario is presented, showcasing the potential of the proposed methodology in similar industrial settings.

Speakers: Dr Alessandro Ferraiuolo (Marcegaglia Steel SpA), Dr Luca Gaia (ICONSULTING SPA)

293 Performance of AI Oriented Contrastive Learning vs Convolutional Neural Networks (CNNs) in Quality Assessment of Zinc Coating Steel Coils

Quality control in zinc-coated steel coils is critical in industries such as automotive and construction, where defects in zinc coating can significantly impact product durability and safety. Traditional manual inspection methods are prone to errors and inconsistencies, especially in high volume production environments.
This paper compares the performance of two artificial intelligence techniques those are convolutional neural networks (CNNs) and contrastive learning, for automated quality assessment of zinc coated steel coils. We evaluate their performance in classifying the quality of zinc coatings, with a focus on defect detection.We implemented both CNNs and contrastive learning models, by using a dataset comprising 4,482 coil profiles with zinc thickness measurements and analyzed their performance. CNNs employed deep architectures with normalization and pooling layers to minimize overfitting, while contrastive learning utilized Siamese networks to learn feature representations from both labeled and unlabeled data.
Experimental results show that CNNs achieved high classification accuracy with an F1-score of 0.93 on the test set and 0.75 on gold-standard data. Contrastive learning, on the other hand, demonstrated variability in performance, with an F1-score of 0.61 for original data and 0.66 after data preprocessing transformations. Statistical analysis indicates that CNNs are robust in scenarios with ample labeled data, whereas contrastive learning excels in feature representation and generalization when labeled data is limited.
These findings have significant implications for real time industrial inspection, suggesting that contrastive learning can be a valuable tool for quality control, especially in situations with limited labeled data. The study also highlights the importance of data preprocessing in enhancing the performance of contrastive

Speaker: Miguel Gutierrez (Universidad Politécnica de Madrid)

294 AI-Powered IT Infrastructure for Enhanced Safety in EAF Operations

The Electric Arc Furnace (EAF) plant in the steel industry presents significant health and safety risks for workers due to extreme temperatures, toxic fumes, and potential operational hazards. To enhance workplace safety, this study proposes an advanced automated system that leverages cutting-edge IT and AI technologies to improve process monitoring and risk prevention.
A key objective of this system is to minimize human presence near the EAF and detect potential hazards in real-time. To achieve this, an IT infrastructure has been developed, integrating a network of sensors—including cameras, microphones, and other data-gathering devices—to continuously monitor the operational environment. This infrastructure provides a comprehensive dataset for AI-driven analysis aimed at improving safety conditions.
The system employs computer vision and various neural network architectures to analyze the area surrounding the EAF. Specifically, it is designed to: (a) detect early signs of incidents by identifying smoke, flames, and abnormal furnace conditions, and (b) monitor workers presence in real-time to automatically halt hazardous operations when personnel is detected within critical zones. These capabilities significantly reduce the risk of workplace accidents by ensuring rapid response to potential dangers.
Currently, a prototype leveraging camera-based monitoring has been developed and tested. This system successfully identifies risk conditions in real-time and tracks personnel proximity to the EAF, demonstrating its potential to enhance safety and automate intervention measures. Future work will focus on refining detection accuracy, integrating additional sensor data, and expanding automation functionalities to further reduce occupational hazards in steel production environments.

Speaker: Prof. Valentina Colla (Scuola Superiore Sant'Anna)

Alternative Fuels & Decarbonization

1.3.3

295 Ecologic and Economic Evaluation of COG Injection and Comparison with other Fuel Gas Injection Systems

The injection of alternative reducing agents into blast furnaces is recognized for its potential to enhance both the carbon footprint and operational costs. Specifically, the use of hydrogen-bearing gases can shift the reduction of iron oxide from carbon to hydrogen, resulting in significant environmental benefits. Recent projects and experiences from the authors' company highlight a changing economic landscape that increasingly supports COG (Coke Oven Gas) injection. The context of CO2 mitigation, advancements in injection technologies, and evolving cost structures make COG injection a viable and cost-effective retrofit option compared to other green technologies with similar effects.
This paper provides a comprehensive summary of recent evaluations and findings, comparing the ecological and economic advantages of the injection of hydrogen-bearing gases. The objective is to assess the impact of fuel gas injection on blast furnace operation, CO2 emission reduction potential, and operational costs (OPEX) compared to a generic reference case without any fuel gas injection. In the initial phase, several combinations of fuel injections with various gas injection rates are simulated and analysed for their impact on blast furnace operation. All impacted changes in the blast furnace operation are analysed with respect to potential changes in CO2 footprint and OPEX. The OPEX analysis takes into account different regions, considering the variations in utility costs and CO2 taxes.
This paper presents the detailed methodology, simulation results, and practical implications of implementing fuel gas injection systems in blast furnace operations, contributing to the ongoing efforts to reduce industrial CO2 emissions and enhance operational efficiency. Additionally, it provides an outlook on the potential uses of the injected gases to further enhance CO2 reduction potential.

Speaker: Dr Michel Haag (SMS group)

296 Pathways for Sustainable Hot Metal Production from DRI to Support Green Steel Production

Gas-based direct reduction (DR) is a key process in low-emission steelmaking due to its flexibility to utilize a variety of reducing agents with lower GHG emissions compared to blast furnace (BF) ironmaking. While direct reduced iron (DRI) and hot-briquetted iron (HBI) produced from low-gangue iron ore are commonly used in electric arc furnaces (EAFs), efficient processing of DRI made from widely available high-gangue iron ore is more challenging. This is a barrier to the widespread adoption of DR process to reduce steel industry emissions.
This study explores the merits of converting high-gangue DRI into hot metal (HM) in BFs to supply high quality iron units for steelmaking. The authors believe that DRI production offers considerable value to integrated steel producers as i) an incremental emissions reduction measure without extensive changes to existing operation; ii) a boost to HM production; and iii) a precursor to future deep, transformational decarbonization flowsheets such as electric smelting furnace (ESF) ironmaking. Process, emissions, and economic drivers are analyzed through physics-based modelling to identify practical scenarios for incorporating DRI in the integrated steelmaking value chain.

Speaker: Sa Ge (Hatch Ltd.)

297 Dry Blast Furnace Gas Cleaning: Technology and Operational Experiences

Dry blast furnace gas cleaning technology offers great economic advantages when compared to traditional wet gas cleaning owing to its improved energy efficiency, lower cost, reduced plot space, and practically eliminated water consumption. The Danieli Corus solution is based upon proven technology that has been applied numerous times for cleaning aluminum smelter gases and anode baking fumes. The system consists of a gas conditioning tower, reagent injection system and (pressurized) filter modules with low pressure pulse cleaning.

This article presents the advantages of the proven technology as well as operational experiences from systems commissioned for greenfield blast furnaces in India.

Speaker: Mr Peter Klut (Danieli Corus)

Digitalization, AI & Process Modeling

2.2.6

Convener: Cosmo Di Cecca (Feralpi Siderurgica)

298 Towards Smarter EAF Steelmaking: AI-Powered Slag Optimization with Real-Time Process Adaptation

In our previous work, we developed an AI-driven system to optimize slag quality in Electric Arc Furnace (EAF) steelmaking. The system utilized neural networks trained on harmonic signal data to assess slag conditions and recommend optimal carbon and oxygen injection profiles. By reducing reliance on operator estimations, this approach improved slag control and process efficiency. However, the initial model focused primarily on harmonic-based slag assessment without accounting for key process variables such as feedstock composition and manually controlled additives.
This study advances the AI system by incorporating Direct Reduced Iron (DRI) composition and lime and dolomite additions—critical parameters that influence carbon and oxygen demand. Since these factors impact slag chemistry, foaming behavior, and impurity removal, their inclusion refines injection strategies to ensure both optimal slag properties and target melt specifications, such as phosphorus reduction and carbon content control.
To achieve this, a deep learning framework leveraging multi-modal data fusion was developed to analyze the complex interactions between harmonic signals, feedstock composition, and additive inputs. The AI dynamically adapts its recommendations in real-time, ensuring that carbon and oxygen injection profiles align with both slag optimization and evolving furnace conditions. The system now integrates operator-controlled variables, allowing for greater adaptability based on real-time process decisions.
Currently undergoing industrial validation, the enhanced system extends harmonics-based slag monitoring by incorporating real-time process data, reducing variability, and improving melt consistency. By expanding AI-driven control to broader operational factors, this work further advances intelligent process optimization in EAF steelmaking, leading to improved efficiency and energy saving, reduced material waste, and more consistent metallurgical outcomes.

Speaker: Farnaz Niknam moghaddam

299 Continuous improvement on process modelling in EAF steelmaking as support to process prediction and management

The technologies related to EAF steelmaking have continuous developments aiming the improvement of the process performances and of the environmental impact mainly through the reduction of energy consumption, the increase of productivity, the increase of metallic yield and promoting the reduction of CO2 emissions.
This necessary development is also confirmed by the further aimed application of EAF technology in new production routes for high quality steels productions presently covered by BF/BOF route having justified this conversion by lower CO2 emissions and increased flexibility of application of EAF technology coupled with DRI charging.
In Feralpi group the steel production is realized with high expertizes in EAF technologies including scrap melting, steel treatments and subsequent solidification in continuous castings for billets in 3 production sites distributed in Italy and Germany. For this reason the necessity to have modern supports to the management of steel production processes is one of the main items.
In last years also thanks to the R&D projects activities Feralpi has realized several steps in the different sites related to the applications of mathematical modelling for EAF processes prediction, process modelling of steel treatment in LF enabling also steel temperature management and prediction of additions in LF.
Further steps of this development included the real time prediction model in EAF the application of alert functions for abnormal energies distribution or chemical injections and related to correctness of steel temperatures in the ladle as support to production management.
The applications realized in different R&D projects are reported including the coupling with plants and sensors development necessary to support the process control.

Speaker: Piero Frittella (Feralpi Siderurgica)

300 Application of Federated Learning to enhance model-based Decision Support for EAF online Monitoring and Control at multiple plants

The Electric Arc Furnace (EAF) for scrap-based steelmaking plays an important role in realizing the transition towards Green Steel production, due to lower carbon dioxide emissions and inherent circularity compared to the iron-ore-based steelmaking.
This work presents an approach to enhance the performance and reliability of a model-based Decision Support System for EAF online monitoring and control by means of Federated Learning, which has been developed within the EU-funded project ALCHIMIA and applied at three EAF plants within the Celsa Group. The system consists of a web application for the characterisation of scrap type properties and a charge mix optimization, which considers multiple optimization criteria like purchase costs and environmental impact factors of the different scrap types. Furthermore, the system includes a dynamic EAF process model based on energy and mass balances and thermodynamic calculations for the online monitoring of the process behaviour and for decision support in real-time control.
The underlying process models and control functions were validated on the basis of historical production and measurement data from a large number of heats produced at the involved Celsa plants. The applied material and model parameters were fitted by means of parameter optimisation tools locally for each individual plant. A selected set of model parameters, which are generalisable for all involved EAF plants, was also optimized by a federated learning approach, to benefit from the information on process behaviour at varying operating points at the involved Celsa plants. This federated learning approach enables the creation of a more generalized global model while preserving data privacy and integrating a monitoring and data drift detection service to capture emerging trends and ensure continuous model adaptation.
The paper will present the model-based EAF decision support system, its performance at the Celsa plants and the benefits of the federated learning approach.

Speaker: Bernd Kleimt (VDEh-Betriebsforschungsinstitut GmbH)

301 Innovative Method for Scanning an Electric Arc Furnace and Digital Twin-Based Simulation of the Tapping Process

The optimization of the tapping process in an Electric Arc Furnace is essential for increasing process efficiency and extending the lifespan of refractory materials. Traditional laser scanning methods for assessing furnace geometry are often costly in terms of acquisition. This study explores an innovative approach to scanning an EAF using photogrammetry-based 3D reconstruction, eliminating the need for conventional laser scanning technology. The generated 3D model serves as the foundation for creating a digital twin of the furnace, which is then used to simulate the tapping process with MAGMASOFT®. By integrating real-world scan data with numerical simulations, this approach provides valuable insights into furnace behavior under various conditions. The findings can contribute to the optimization of maintenance strategies and operational best practices, enabling steel producers to improve refractory durability and reduce unplanned downtime. This study demonstrates the potential of photogrammetry-based scanning as a cost-effective and accessible alternative to traditional methods, making advanced furnace monitoring and process optimization more practical for industrial applications. The integration of 3D scanning, digital twin modeling, and numerical simulation represents a significant step toward the digitalization and automation of EAF operations, paving the way for increased efficiency and sustainability in steel production.

Speakers: Adrian Plieth, Mr Evgenii Shvydkii

302 SmartKnB: Artificial Intelligence tools for EAF Optimization

SmartKnB is an innovative programming platform engineered for advanced control of the Electric Arc Furnace (EAF) steelmaking process. By integrating diverse data sources—from sensor arrays and PLCs to historical logs and real-time imagery—SmartKnB enables the development, testing, and validation of sophisticated control algorithms in a modular, node-based graphic environment. As the core of AMI SmartFurnace technology, all the control algorithms are implemented through SmartKnB. SmartFurnace is a comprehensive optimization system that dynamically adjusts electrical and chemical energy inputs based on real-time process data, improving process safety, efficiency and reduced emissions.
In addition, SmartKnB can be used to implement from traditional control methods to the most modern machine learning models. Including advanced image processing capabilities it can use pre-trained models facilitating automated image classification and anomaly detection—crucial for monitoring raw material issues and furnace conditions. Together, these integrated functionalities can contribute to enhance process efficiency, better energy management, and greater operational safety, allowing a smarter and more sustainable steel production.

Speaker: Emmanuel Placier (AMI)

303 CALPHAD-based Thermodynamic and Kinetic Simulation of Secondary Steelmaking with Focus on Inclusion Formation and Modification

The evolution of steel and slag chemistry in function of secondary metallurgy process parameters can be simulated with good accuracy using Thermo-Calc’s TCOX CALPHAD database and the effective equilibrium reaction zone (EERZ) model that accounts for reaction kinetics.
An interesting aspect of such simulations is tracking the formation and modification of endogenous non-metallic inclusions throughout the process. The TCOX database contains thermodynamic descriptions of all important non-inclusions allowing their amount and composition to be calculated in function of evolving steel chemistry.
Most inclusions form during deoxidation of the steel. But slag entrainment during tapping is also an important source of inclusions. During secondary metallurgy these inclusions will be gradually removed from the steel by flotation, but their minerology will also change over time in function of the changing steel chemistry. Inclusions can be modified intentionally: solid Al2O3 (Corundum) inclusions can be transformed into liquid Ca-Al-Oxides by calcium treatment. But they can also change without making any additions: Al2O3 might transform into MgAl2O4 Spinel due to MgO pickup from the ladle lining. Oxygen activity in the steel is an important driver for the type of inclusions that are formed. A high oxygen partial pressure will directly result in the formation of oxide inclusions. A very low oxygen activities will drive S out of the steel into the slag, leading to the dissolution of sulfide inclusions. At the same time most other elements, notably Si, will be reversed out of the slag back into the steel with potentially unwanted effects.
It will be shown how Thermo-Calc and the TCOX database can be used to calculate the thermodynamic stability of inclusion in function of steel chemistry, temperature and oxygen activity and how kinetic simulations can shed light on the evolution of inclusions in function of time during secondary steel making.

Speaker: Dr Anthony Nicholas Grundy (Thermo-Calc Software AB)

Digitalization, AI & Modeling

2.3.5

Convener: Carlo Mapelli (Dipartimento di Meccanica - Politecnico di Milano)

304 Flow and solidification modeling in continuous casting of steel: an European expertise mapping at a glance and positioning at a global level

Recent advancements in modelling, involving approach and computing power, are transforming the industrial, and particularly the metallurgy sector, providing more precise tools for quality control and process optimization
In the context of continuous casting of steel, modelling techniques provide for an accurate optimization of the process parameters, such as casting speed, layout geometry and secondary cooling, to minimize surface and internal defects as cracks and segregations. Moreover, the use of advanced numerical simulations and thermal analysis helps predicting dendritic structures and undesired porosity occurrence, thereby allowing to improve the quality of the final product. In general, the modelling approach can involve fundamentals of thermodynamics, solidification kinetics, fluid dynamics highlighting the interplay among heat flow, mass transfer, and thermal stresses, also finalized to predict microstructure formation and defect control. The integration of advanced technologies, such as artificial intelligence and machine learning, is opening new frontiers in solidification modeling, allowing for greater precision and adaptability of models to various production processes, as well as in setting up tools integrated with dedicated sensoring for online process and quality control
A comprehensive review of solidification modelling in continuous casting, developed in the frame of an EU - RFCS funded project (METACAST) is then presented to map at a glance, approaches and research groups present in Europe, to identify common lines between models and compare EU expertise with non-EU ones.

Speaker: Michele De Santis (Rina Consulting - Centro Sviluppo Materiali SpA)

305 A comparative CFD study on tundish flow with particle tracking

Continuous casting machine (CCO) is fundamental to produce steel at reasonable costs. The tundish represents the main source of steel for this kind of facility, acting as a buffer between the ladle and the nozzles feeding casting profiles. This component significantly influences the quality and yield of continuous casting operations. Our study focuses on leveraging Computational Fluid Dynamics (CFD) to track particle behaviour within the tundish. By simulating the flow patterns, we aim to optimize tundish design in terms of steel cleanliness. We defined two main scenarios that have different impact on molten steel flow and inclusion transport, with the intention to minimize defects and enhance overall efficiency.
Our approach involves tracking individual particles—both in terms of trajectory and residence time—allowing us to understand their impact on product quality. A huge postprocessing has been done in python on order to perform analysis in a structured framework, making comparison of the two cases much easier.
Finally, the head reason is to reveal by simulations how inclusions move and could accumulate within the steel flow. This kind of knowledge prompt strategies to reduce inclusions in the final product.

Speaker: Philippe Brunier (Cogne Acciai Speciali)

306 CC Process optimization through combined digital twin and in-line measurement technology for a stainless-steel slab production

The degree of digitalization in steel producing companies is increasing significantly, which consequently amplifies the importance of identifying significant process parameters and investigating the effect of parameter changes.

Digital simulation technology today makes it easily possible to carry out three-dimensional process simulation of the entire continuous casting process. State-of-art simulation tools provide quantitative insights into formation of flow, solidification, stress and distortion. Recent developments in modelling of electromagnetic stirring (EMS) and its impact on the flow behaviour as well as thermomechanical coupling with simulation of stress development, up to the slab’s interaction with rolls and bulging effects, can be considered.

By integrating MAGMA CC’s digital twin technology with mecorad’s radar-based solutions, virtual experimentation is combined with real-time in-line measurements. Thus, information about quality, productivity and energy saving potential of process alternatives can be examined more precisely and beneficially.

Whereas many secondary parameters can be examined throughout the casting process, primary parameters of the product can only recently be obtained from inside the casting machine as early as the mold exit using the radar technology from mecorad. The WTL series delivers continuous real-time values of strand dimensions uninfluenced even by conditions in the secondary cooling zone, which allow a proactive, in-line intervention and optimization of the casting process. Combined with radar-based mold level control, deviations from optimum simulations become visible to the operator immediately.

In this manner, expensive and energy intensive experimental trials can be avoided and replaced with the digital twin technology of MAGMA CC in conjunction with in-line measurement from mecorad. Based on this knowledge, the optimized casting processes are both cost- and energy-efficient, as well as robust with respect to final product quality.

These findings have been validated on an industrial-scale continuous slab casting machine, demonstrating the effectiveness of combining digital twin technology with real-time radar-based measurement.

Speaker: Dr Marc Banaszak (mecorad GmbH)

307 ADVANCING CONTINUOS CAST SEMI-PRODUCT QUALITY THROUGH A DIGITAL TWIN FRAMEWORK

The quality of continuously cast steel semi-products (e.g., slabs, billets, and blooms) is fundamental to the efficient production of high-performance steel products for demanding markets. To achieve high casting speeds while maintaining quality, numerous control and monitoring technologies have been successfully developed, even for challenging steel grades.

Recent advancements in phenomena-based modeling, predictive analytics, and deep learning-based quality assessment offer significant potential for enhancing the casting process. Each of these technologies contributes uniquely to process optimization, and their integration into a unified, multi-disciplinary digital framework will enable sophisticated, automated process control.

This paper presents Sapotech’s pioneering Digital Twin architecture, which integrates real-time continuous casting process monitoring with Deep Learning-based quality analysis and model-based quality predictions. This approach provides a unique solution that not only delivers numerical and visual feedback on AI-driven quality assessment but also establishes a real-time, interactive visualization of the relationships between process parameters and product quality. At its core, the system incorporates a 3D Digital Twin model of the continuous casting process, combining real-time process data with predictive AI and physics-based modeling. By integrating Sapotech’s AI-driven semi-product surface quality assessment within this framework, a fully integrated, online quality feedback loop is achieved, enabling continuous process management, improved defect detection, and enhanced process stability, ultimately ensuring that operations remain within an optimal and acceptable performance window.

Speaker: Saku Kaukonen (Sapotech Oy)

308 An OpenFOAM Eulerian-Lagrangian Model of a Polydisperse Bubbly Flow in a Continuous Casting Mould

Some defects in continuous cast (CC) steel are the result of flow conditions at the top section of the CC mould. To monitor and potentially control the flow, in order to reduce such defects, information about the flow conditions is needed. In addition to sensors that may be installed on the mould, CFD can provide detailed insight into the mould flow. We are developing an OpenFOAM-based Eulerian-Lagrangian multiphase flow solver for such simulations, based on an existing OpenFOAM Lagrangian solver, DPMFoam. One limitation of that solver is that the size of particles or bubbles be much smaller than the mesh size, in order to produce accurate results; this constraint limits the use of mesh refinement in regions of interest, and hinders obtaining grid independent results. Another limitation of the Lagrangian method is that the free surface between water and air atop the mould is not modeled. In this work, a multi-stage diffusion method has been added to the OpenFOAM solver DPMFoam, to resolve the restriction of particle to mesh size; and a Volume of Fluid method has been added to the solver to model the water/air free surface. Simulation results of polydisperse bubbly flows in a CC mould will be presented, and those results compared to corresponding experimental data from a full scale water model of the top of a CC mould, focusing on the behaviour of bubbles as a function of size, and of fluctuations of the water/air free surface, as a function of various casting conditions.

Speaker: Saeid Amirzadeh

309 Motion behaviors of non-metallic inclusions at the steel/Ar/slag interfaces considering interfacial physical parameters: an in-situ observation study

Inclusion engineering is a comprehensive concept dealing with the control of amount, size distribution, and chemical composition of non-metallic inclusions in advanced steels. Furthermore, it also concerns the correlation between inclusion, microstructure and property on the quality control of the final product. This work aims to summarize the research activities of the authors regarding the inclusion motion and agglomeration at the steel/gas/slag interfaces, inclusion dissolution in the slag, and fine inclusion induce intragranular acicular ferrite (IAF) nucleation in solid steels. Several aspects of interfacial phenomena, including interfacial energy, contact angle between inclusion and metals, surface tension of metals, viscosity of silicates, etc. are considered in the theoretical models to investigate the mechanism. For instance, the capillary force is found to be the main reason of inclusion agglomeration at the steel/Ar interface, the difference of interfacial energy between inclusion/ferrite and inclusion/austenite affects the nucleation barrier of IAF formation from the inclusion surface. Physical parameters are collected from either open literature as well as measurement. Last but not least, the inclusion motion behaviors at the surface of molten hydrogen plasma reduced iron is also mentioned in this work. This work aims to provide insights of the theoretical mechanism considering interfacial phenomena contributing to ‘inclusion engineering’.

Speaker: Prof. Mu Wangzhong (Lulea University of Technology)

Direct Reduction & Alternative Ironmaking

5.2.3

Convener: Prof. Davide Mombelli (Politecnico di Milano - Dipartimento di Meccanica)

310 Replacement of Conventional Gas Burners with Electrical Resistive Heating for Tundish processes: A Sustainable Approach within the CITADEL Project

The transition to sustainable steel production is a critical challenge in reducing the environmental impact of high-temperature metallurgical processes. While basic oxygen route steelworks are nowadays focused on the development of new production processes for decarbonization of the iron reduction, the Electric Arc Furnace (EAF) route producers have the potential to eliminate almost all their CO2 emissions by using renewable electric power and green hydrogen in their existing production facilities.
One significant area for improvement is the tundish pre-heating process, traditionally reliant on fossil fuel-based burners,. that contribute to CO2 emissions and inefficiencies . The present study, conducted within the framework of the Horizon-funded CITADEL project, explores the feasibility of replacing conventional gas burners with an electrical tundish pre-heating system, aiming to enhance energy efficiency and reduce the environmental footprint of continuous casting operations.
A numerical model was developed to simulate heat transfer dynamics and temperature distribution within the tundish. Modelling results indicate that electrical tundish pre-heating has the potential to provide a more uniform heating profile, reduce energy consumption, and eliminate combustion-related emissions. Ongoing work includes the design and implementation of experimental trials to validate these findings under industrial conditions. Future experimental investigations will assess key performance indicators such as temperature homogeneity, refractory wear, and overall process stability.
The results of this study align with the objectives of the CITADEL project, which focuses on advancing low-carbon solutions for the steel industry. By demonstrating the potential of electrical tundish heating, this research supports the broader adoption of electrification strategies, contributing to the decarbonization of steel-making and the achievement of EU climate targets.

Keywords: Tundish, modelling, heat transfer, CITADEL

Speaker: Björn Glaser (KTH)

311 Simulation-driven comparison and investment prioritization of gas-fired and electric radiant tubes in galvanizing furnaces.

The operation of strip/coil galvanizing furnaces is significantly influenced by the choice of heating technology, which affects thermal uniformity, energy consumption, service life, maintenance costs, and CO2 emissions. Traditionally, gas-fired radiant tubes have been widely employed. However, the transition to electric heating solutions presents potential advantages in terms of thermal homogeneity, energy efficiency, durability, and reduced carbon footprint. A key challenge in this transition lies in evaluating the comparative performance of these two technologies under real operating conditions to support strategic plant investments.
This comparative study applies Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) simulations to develop a representative virtual model of a galvanizing furnace equipped with both traditional gas-fired U-shaped radiant tubes and electric heating elements. The model captures combustion phenomena for the gas system, heat transfer mechanisms across the furnace, and the local thermal deformations and induced stresses affecting tube longevity. The impact of each heating technology on the homogeneity of thermal distribution on the coil and on the radiant tubes, overall power consumption, CO2 emissions, and expected critical regions affecting tubes service life are analysed. Additionally, maintenance costs associated with the two solutions are assessed.
The model is used to compare the current operational practices with alternative configurations, identifying key trade-offs between energy efficiency, temperature uniformity, CO2 emissions, and long-term maintenance requirements. By integrating these insights, the study provides a quantitative basis for prioritizing plant investments, optimizing furnace operation, and facilitating the transition toward more sustainable and cost-effective heating solutions in galvanizing processes.

Speaker: Mr Marco Bertoli (Astarte Strategies Srl)

312 Advancements in Electrification and Decarbonization Technologies for High-Temperature Process Heating in Steel Manufacturing: The Role of Coolbrook's Rotodynamic Technology

This paper presents Rotodynamic heating technology, which enables the decarbonization and electrification of the steel industry for high-temperature process heating, in line with its transition towards a fossil-free future. The steel industry is undergoing significant changes in its pursuit of carbon neutrality, demanding innovative solutions.
The paper compares various decarbonization methods, including CCS (Carbon Capture and Storage), green hydrogen production, hydrogen utilization as an energy source, and biofuels, alongside the Rotodynamic technology to provide an analytical view on the most cost-effective pathway for decarbonization of high-temperature process heating. To date, electrification has faced challenges in achieving high temperatures with large volumes and substantial power requirements using electric heaters.
Coolbrook’s Rotodynamic technology represents a new direct electrification method capable of achieving high temperatures and handling large volumes efficiently. Identified applications in steel production span across multiple process stages and all manufacturing routes, including blast furnace, DRI, hydrogen reduction, and scrap-based steelmaking. Economic comparisons have been utilized to demonstrate the technology’s viability.
The need for electric heating is expected to increase, particularly in new hydrogen-based solutions that generate fewer process gases. This paper focuses on a selected concrete application of a significant steel manufacturing use case and concept, with an analysis showing that it is an effective decarbonization method that reduces both OPEX and CAPEX.

Speakers: Dr Timo Paananen (Coolbrook), Viljami Maakala (Coolbrook)

313 Alternative Annealing Process for NGO Electrical Steels Using Hydrogen Combustion: A Comparative Study

To reduce CO2 emission H2 could be used as a fuel for energy intensive thermal processes such as hot rolled strip annealing. This article presents approach and results of laboratory trials at developing an alternative CO2-free fuel application for the annealing of Non Grain-Oriented (NGO) electrical steels in the annealing and pickling line (APL), where the annealing of the material is carried out using fumes from Hydrogen combustion instead of natural gas. To understand the differences produced by the use of the two different atmospheres, oxidation tests were conducted on high Silicon percentage (3.16%Si-1.04%Al) hot-rolled steel strips at various temperatures and different air/fuel ratio . The evaluations conducted included considerations on productivity as well as the impact of Hot Band Annealing (HBA) on the main properties which are known to affect the quality of the finished products. Descaling and pickling tests were carried out, which allowed predictions on the process productivity. SEM investigations with EDS and XRD analyses were conducted to identify differences in morphology and composition of the scale present at the end of HBA with particular attention to the formation of the Iron silicate (Fe2SiO4) known as fayalite. Possible residues of internal oxidation at the end of the pickling process were also checked. Potential nitriding and carburization phenomena that may occur to different extents within the two atmospheres were investigated using a CNS elemental analyzer. To obtain a comprehensive overview, the analysis also included observations of the microstructure of the annealed and pickled material. The process under examination was evaluated as its adoption could allow an elimination of direct CO2 emissions up to 50 kg per ton of steel.

Speaker: Niccolo Massarelli (RINA Consulting - CSM)

314 Bio-char production and usage for iron ore pelletization

In the race towards Net Zero, ArcelorMittal is committed to reduce their CO2e emissions by 30% in Europe and 25% worldwide by 2030. To achieve these ambitious goals, the group is looking at using (and potentially self-producing) bio-chars to substitute fossil fuels (coal and coke) in the different iron and steel-making processes. Here, the production of bio-chars for the substitution of coke breeze in iron ore pelletizing is explored. In order to be applicable in the existing plants and maintain iron ore quality, bio-chars need to meet several Key Process Indicators (KPIs). These include prescriptions on minimum calorific value, maximum ash content and oxides in the ash. In this work, slow pyrolysis of forestry residues was carried out at different temperatures, and mass and energy balance were performed to allow for a techno-economic assessment of bio-char production. The different bio-chars were characterized and compared with the KPIs to determine the technical feasibility of coke breeze replacement with bio-char. An economic assessment of the biochar utilization in iron ore pelletizing was drafted.
Results show that bio-chars can be used in replacement of fossil fuel in iron ore pellets. Nevertheless, careful selection of raw biomass is mandatory to meet the process KPIs. Bio-char usage may represent an economically viable solution, provided environmental policies and raw materials market are favourable. Slow pyrolysis trials indicate that bio-char mass yield varies between 20-40% (in dry basis), depending on process temperature and feedstock. The energy balance carried out on the feedstock (input) and pyrolysis products (output) reveals that bio-char represents the main energetic resource. Self-production of bio-chars from secondary raw materials (like forestry residues) may represent a sustainable solution to reduce ArcelorMittal’s CO2 emissions in steel industry, provided all pyrolysis products are fully exploited.

Speaker: Beatrice Crocco (ArcelorMittal Maizières Research)

315 Industrial Implementation of PyroLIBS for Continuous Hot Metal Chemistry Measurement

The PyroLIBS system is a next generation technology for pyrometallurgy, capable of continuous and instant measurement of chemical compositions for molten materials. The present paper presents the early results of its first industrial implementation on a blast furnace runner, for continuous hot metal chemistry and temperature measurement.

Speaker: Bijan Shahriari (Hatch)

Forging

3.2.1

Convener: Dr Gerhard Hackl (ASMET)

316 Effect of Intermediate Intercritical Quenching on Low Temperature Toughness of Low-alloy Steel Forgings

Typical heat treatment of structural steel forgings consists of quenching and tempering (QT). However, in case of heavy forgings (thickness above 120 mm), made of steels with carbon content less than 0.25% and low hardenability, the required strength can be achieved, but low temperature impact toughness could be not fully adequate. In this work, an intermediate intercritical quenching (IIQ) process, introduced between the conventional quenching and tempering treatments, was studied to improve the low-temperature toughness of heavy forgings made of low-alloy steels with C < 0.25%. After a design phase of the IIQ, validation of the proposed new heat treatment (Q+IIQ+T) was carried out by laboratory tests. The possible benefits of the IIQ treatment were evaluated comparing the mechanical properties and microstructures of forged coupons subjected to standard QT, double QT and Q+IIQ+T. Particular attention was paid to the toughness of the materials, which was measured by standard Charpy testing (V-notch transverse specimens) and fracture mechanics according to ASTM E1921 for determining the KJd (dynamic) parameter. The experiments showed that the introduction of the IIQ treatment, while maintaining the strength levels within the target values, leads to a considerable increase of low-temperature impact toughness, compared to the single QT and double QT, for the investigated steels (0.12-0.16%C, 0.7-1.35%Mn-1.5-2.0%Ni). A mixed microstructure was obtained after Q+IIQ+T, containing very fine ferrite and tempered martensite, which allows to achieve excellent low-temperature toughness. This behavior was attributed to microstructure refinement through reversed transformation during intercritical annealing. An industrial validation of IIQ was performed by manufacturing some prototype forgings that were investigated in terms of microstructures and mechanical properties. The industrial results confirmed that tensile strength of 490-510 MPa and yield strength of 340-380 MPa can be achieved with very high toughness levels, even in case of large thickness (up to 350 mm).

Speaker: Dr Ettore Anelli (Franchini Acciai SpA)

317 Advanced Ring Rolling Simulations with Embedded Machine Control Systems

Radial axial (RAW) ring rolling is a well-established incremental forging process producing seamless rings and shells, both with rectangular as well as profiled cross sections, with high demands in terms of mechanical properties and microstructure, standing out for its productivity. Rolled rings and shells are applied in many industrial fields, e.g. wind power, nuclear industry, general construction of vessels, flanges, valves, bearings.
Although finite element (FE) ring rolling simulation coupled with closed-loop control is sometimes reported as state of the art, the process control was only approximated before. Due to this, very large rings and large profiled rings have proven almost impossible to simulate. A direct coupling between FE-simulation and the real RAW machine control overcomes these difficulties by utilizing the sophisticated control algorithms enabling real-world virtual production of such very large rings.
To simulate ring rolling processes as close to reality as possible the real machine control (CARWIN) is embedded in the FE-simulation. This comprehensive physical model with realistic boundary conditions represents all degrees of freedom that can also be found in real-world ring rolling processes without any additional stabilizing measures. It accounts for process limits as well as for limits of the radial-axial ring rolling machine, has an analogous look-and-feel to the control desk in the control cabin and is suitable for rings and shells of all dimensions, even very large ones, with rectangular as well as profiled cross-sections. Feasibility has been proven and the model is validated by industrial ring rolling processes, e.g. 5 tons profiled ring, 22 tons shell, 13 m profiled ring (85 tons).
The machine control including interface to the FE-simulation - Rolltech RPS - operates independent and can be implemented in various commercial FE-softwares. A roll-out to SMS group ring rolling machine operators, with emphasis on accessibility for SME, is prepared currently.

Speaker: Dr Koos Van Putten (SMS group)

318 Optimization of Process Control and Energy Consumption in Hot Flat Ring Rolling Using Interactive Real-Time Software

Hot Radial Axial Ring Rolling is a crucial process in seamless ring production for various industrial sectors, ranging from oil & gas to aerospace. To configure and optimize this complex process, modern rolling mills rely on computerized controls, where operators must input process parameters derived from multiple sources-including tables, formulas, experience, and time-consuming FEM simulations. The process requires highly accurate and consistent input, as many parameters are interdependent through complex correlations, making it challenging to predict the outcome when modifying one or more settings. At the same time, optimizing energy consumption has become a key priority in both industry and research, as it significantly impacts production costs and environmental sustainability.
The proposed real-time software package assists operators by automatically determining all necessary parameters for controlling the rolling process based on final ring dimensions, material properties, temperature, and machine settings. It interactively suggests blank ring dimensions,suitable tools, rolling curves, and ring growth strategies to minimize process time and energy consumption. Through a graphical user interface, operators can modify or compute any parameter, gaining a faster yet deeper understanding of the production process while optimizing rolling time and total energy requirements. The software communicates the optimized process parameters directly to the rolling mill’s control requipment and generates a post-process log file for verification. It has been validated through multiple industrial production runs and FEM simulation replicas, confirming its effectiveness in minimizing energy consumption while maintaining process efficiency.

Speaker: Mr Marco Munari (Project Group s.r.l.)

319 Development and application of measurement systems in forging process

The development and application of measurement systems in forging process play a crucial role in optimizing production efficiency, ensuring product quality and reducing operational costs.
This presentation will discuss the development over time of various measurement technologies implemented in our forging shop and explore potential future improvements. It will highlight the evolution of measurement systems used to monitor key parameters during the hot forging process, focusing on both the advancements in accuracy and the integration of new technologies. The presentation will cover the challenges faced in adapting these systems to high temperature environments and the impact of these innovations on production efficiency, product quality and process control.
Additionally, we will examine ongoing research and potential future development aimed at further enhacing measurement capabilities with a particular emphasis on automation and real time data analysis. Attendees will gain a deeper understanding of the continuous improvements in measurement technologies and their role, also thanks to the practical applications of the systems, in shaping the future of forging processes.

Speaker: Mr Nicholas Esquisito (Cogne Acciai Speciali)

320 ENERGY SAVING ON A 70 MN OPEN DIE FORGING PRESS

VID, acronym of Virtual Inertia Drive, is the new hydraulic drive that Danieli proposes in forging open die applications.
His aim is to keep the same size and performances of a conventional forging machine, but reducing the total electrical power installed, the n° of motor-pumps unit and the energy consumption.
System is made by the following components :
1. Hydraulic pumps
2. Flywheel
3. AC motor  4 poles standard motor
4. Inverter
The cyclical nature of the forging process makes the VID system perfect for this type of application. The pulsating load required by the pumps is met by the flywheel which releases energy by decelerating during the forging phases when there is the peak of pressure. During the rest phase (the return of the movable crosshead), the pumps are discharged into the tank, and the flywheel is re-accelerated to nominal speed thanks to the inverter.
The VID’s benefit is not only during the forging process, but also during the handling phases of the ingot. In this condition typically the conventional drive runs at the nominal speed in idle condition (no load) to not exceed the limit of start/stop of the motor in an hour. With the VID system Danieli can put the motors in excess on stand-by and can reduce the speed of the motor pumps that are necessary to make the auxiliary movements (main slide or die storage for example). This allows to obtain relevant energy saving during the change of tools of the machine.

Speaker: Mr Mauro Baldassi (Danieli & C. Officine Meccaniche S.p.A.)

321 A combined experimental–numerical approach to assess the effects of quenching transfer time on the microstructure and mechanical properties of a Ti-6Al-4V alloy

Nowadays, titanium (Ti) alloys play a pivotal role in aerospace and energy production sectors due to their specific mechanical properties. To date, the design of forged components in Ti alloys has been based on the experience of operators and engineers, and on the use of industrial tests to optimise production processes. However, the high production costs of these components and their possible anisotropy have led to the development of numerical models to assist engineers in designing the entire production cycle, thus reducing the number of industrial tests.
This work aimed to develop a combined experimental and numerical approach for the study and prediction of the effects of transferring time to the quenching bath on the microstructure and mechanical properties of a real industrial component made of the Ti-6Al-4V alloy. First, the thermal properties of the alloy were validated by comparing numerical and experimental results, the latter obtained at both laboratory and industrial scales, and by adjusting the input simulation data to fit the experimental measurements. The validated model was used to conduct multiple heat treatment simulations of the industrial component with varying transfer times to the quenching bath. For each simulation, time-temperature curves were obtained at different depths from the surface of the component. The calculated data were then discussed and compared with the experimental results from the same heat treatment routes performed at a laboratory scale on representative Ti-6Al-4V samples. On these samples, the subsequent metallographic and mechanical analyses enabled to establish quantitative relationships between the transfer times and the microstructural and mechanical properties of the material. The results were reasonably consistent with data obtained from the real component, confirming the validity of the proposed predictive method.

Speaker: Dr Davide Maghini (Department of Engineering, University of Ferrara)

Quality Control & Inspection

3.1.4

Convener: Alessandra Saleri (Forge Fedriga srl)

322 Online and Real-Time Recrystallized Fraction Estimation in Steel Rolling Processes by Laser Ultrasound

This study introduces an innovative method for estimating accumulated strain and recrystallized fraction in steel using the existing online laser ultrasonic (LUS) grain size gauge [1]. This method extends the capability of the grain size gauge by extracting more information from the same measurement. The method leverages the detection of shear wave splits, observed as small shear-wave echoes splitting into two distinct echoes, to estimate accumulated strain. By comparing this LUS-measured strain with the total rolling reduction, an implicit measure of the recrystallized fraction (RX) was achieved. This approach is based on the principle that a fully recrystallized material exhibits near-zero accumulated strain, while a non-recrystallized material shows strain equal to the total engineering strain.
The method has been validated against cold rolled austenitic stainless steel with 0 to 80 % deformation. The observed shear wave splits, attributed to material texture changes due to the rolling reduction, were correlated with accumulated strain.
Previous suggestions for measuring the texture with LUS [2,3] required special optics to scan the material in different directions whereas this technique works with a single LUS measurement in the normal direction making the method much more robust. This technique therefore offer the ability to provide real-time feedback for process control without reducing the measurement frequency for the grain size gauge. The method's application in hot rolling processes demonstrates its potential to optimize material properties and improve process efficiency during hot rolling.
[1] M. Malmström et. al, Laser-Ultrasound-Based Grain Size Gauge for the Hot Strip Mill, Appl. Sci. 12 (2022) 10048. https://doi.org/10.3390/app121910048.
[2] M. Malmström et. al, Application of Laser-Ultrasonics for Evaluating Textures and Anisotropy, Appl. Sci. 12 (2022) 10547. https://doi.org/10.3390/app122010547.
[3] M. Malmström, et. al, Comparative study of structures in cold rolled 316 stainless steel using laser ultrasonics and electron backscatter diffraction measurements, in: ESTAD 2021.

Speaker: Mikael Malmström (Swerim AB)

323 Study on shape defects of thin steel sheets caused by steep longitudinal temperature gradient

In the steel industry, the rapid cooling process, which is suitable for manufacturing high-strength materials, is being increasingly applied. However, the deformation caused by rapid cooling is particularly large, which leads to reduced productivity and yield, so suppressing this deformation is an important issue. In order to suppress deformation, it is first necessary to quantitatively evaluate the shape of the steel sheet during quenching. Possible causes of shape defects in steel sheets during quenching include temperature deviations in the thickness, width, and longitudinal directions of the steel sheet. However, there have been no reports of defects in the shape of steel sheets caused by a steep longitudinal temperature gradient. Therefore, the effects of steel type and operating conditions on shape defects of thin steel sheets accompanied by martensitic transformation due to a steep longitudinal temperature gradient were quantitatively evaluated by FEM analysis. The results showed that, during steel sheet quenching, Dual Phase steel did not generate much compressive stress in the width direction, but full martensitic steel buckled and generated wave shape due to compressive stress in the width direction in the transformation expansion area. It was also clarified that, during the manufacturing of full martensitic steel by the quenching process, the average warping height increased with increasing width, temperature gradient, and initial warping height.

Speaker: SOSHI YOSHIMOTO (JFE Steel Corporation)

324 Vision Technology-Based Surface Quality Optimization for Continuous Hot-Dip Galvanizing Process

During the continuous hot-dip galvanizing process, numerous parameters directly correlate with the surface quality of steel plates. Among these factors, the emission management of floating oxides on the zinc bath surface within the snout represents a critical operational parameter for maintaining continuous production efficiency. To address this challenge, various steel manufacturing companies have invested substantial efforts in equipment-based solutions. However, the conventional operational methodology, which relies on manual operator observation, fails to effectively suppress the incorporation of floating oxides into the steel plates, resulting in compromised surface quality within the snout. This research and development aims to optimize the surface quality management of steel plates within the snout by developing an intelligent technology that integrates computer vision algorithms with automated facility control systems and implementing this solution in industrial applications.

Speaker: TAE JUN PARK (Hyundai-steel)

325 New insights from the online LUS grain size measurements

In a collaborative initiative, an innovative Laser UltraSonic (LUS) device was installed at the SSAB Hot Strip Mill in Borlänge. This measuring device, along with the software for signal processing and evaluation, was developed, constructed, and implemented through a partnership involving SSAB, SWERIM, EMG, and the SMS group. Positioned after the last rolling stand in the finishing mill, the measurement of austenite grain size is taken immediately after rolling.

The LUS measurements were conducted on various steel grades with differing dimensions and process parameters. The calculated process data of the tested strips were sourced from the SMS process models (pass schedule model PSC® and cooling section model CSC) and underwent comprehensive analysis alongside the measured process data and austenite grain size. This analysis encompasses the entire process, beginning with the discharge of slabs from the reheating furnaces, through the roughing mill, coil box, finishing mill, cooling section, and concluding with the downcoiler. Extensive recalculations using the PSC® and CSC were performed to quantify the correlation between the measured austenite grain size and the process conditions of the rolled strips.

The detailed recalculations demonstrate a strong correlation with the measured grain sizes. Based on the results, e.g. variations in the transfer bar thickness were made, leading to a more equal grain size along strip length, which has also a noticeable effect in following cold rolling process.

In the near future, the LUS measurements could be integrated into the Level 2 automation system, enabling the use of austenite grain size within the pass schedule model PSC®, the cooling section model CSC, and the microstructure property model MPM. Consequently, these models could utilize austenite grain size as a setpoint for direct process control in the hot rolling mill, thereby improving the control of product properties and minimizing downgrading.

Speaker: Dr Dietmar Hoppe (SMS group)

326 Advanced robotic system for automated plate processing: precision, efficiency, and seamless integration

This paper presents an advanced robotic system designed to automate key quality control and marking processes for plates exiting the rolling mill. The solution integrates shaping automation (contour and flatness control), defect detection, thickness measurement, ink marking, and stamp marking, ensuring high precision and efficiency.

An advanced vision system enables real-time conformity checks, comparing customer specifications with actual plate data. This allows for automatic classification of non-compliant plates, which can be discarded, downgraded for alternative orders, or reprocessed for requalification. The system also features a user-friendly HMI, enhancing safety and optimizing robot operation management.

A key advantage of this solution is its seamless integration into existing plants, significantly reducing investment costs while enabling incremental implementation in multiple phases. Additionally, the system provides an opportunity to incorporate a product tracking platform, enhancing traceability and process optimization throughout production.

Speaker: ION RUSU (POLYTEC SPA)

327 In-Situ Grain Size Measurement During Hot Rolling Simulations With Dynamic Recrystallization By Laser Ultrasonics

The real-time grain size measurement has recently been realized by laser ultrasonics in the hot-rolling process [1]. This enables quality control, the possibility of direct feedback to the process control system, as well as feedback to the set-up calculation which is performed before each transfer bar is sent through the finishing mill to be rolled. The gauge provides novel insights into how the material behaves during production. This is especially useful for low-alloyed steels that phase transform at cooling to room temperature making it difficult to use traditional metallographic methods to estimate prior austenite grain structure.
However, the grain size gauge is currently only installed at one position in the mill, thus, providing measurements at a single point in the process. To better understand how material behaves during the whole process the GLUS® testbed at Swerim, which is the combination of the thermo-mechanical simulator GLEEBLE and laser ultrasonics can be used. The method provides a unique possibility to explore and validate alloying concepts on a smaller scale to increase the understanding of how material properties evolve during for example annealing or hot-rolling processes. Here, this is demonstrated for austenitic stainless steel making it possible to confirm LUS measurements with room temperature observations.
Thermomechanical simulations are made corresponding to a 6-stand finishing mill, with different deformation strategies reaching the same total deformation. Grain structure is monitored with laser ultrasonics on 316L. In addition, we will present the results from grain size measurement during the deformation showing the capability of GLUS to capture the microstructure evolution such as dynamic recrystallization.
References
[1] Malmström M, Jansson A, Hutchinson B, Lönnqvist J, Gillgren L, Bäcke L, et al. Laser-Ultrasound-Based Grain Size Gauge for the Hot Strip Mill. Applied Sciences 2022;12:10048. https://doi.org/10.3390/app121910048.

Speaker: Mikael Malmström (Swerim AB)

Process Optimization & Control

6.1.2

328 Enabling Batch Process Flexibility Through Electricity Market Interfaces in Steel Production

The transition to sustainable steel production necessitates innovative strategies for managing electricity demand in energy-intensive batch processes. Unlike large-scale continuous operations, small and medium-sized enterprises (SMEs) in steel manufacturing—such as specialized foundries and long product rolling mills—face unique challenges due to smaller batch sizes, greater product complexity, and the necessity for highly flexible scheduling. These companies must dynamically adapt to volatile energy markets while maintaining production efficiency and competitiveness.

This paper presents a conceptual framework tailored to SMEs for integrating electricity market signals into production planning and execution, enabling real-time demand response and load shifting. By leveraging scientific models for forecasting, optimization, and real-time analysis, the proposed software modules enable flexible production planning (e.g. day-ahead scheduling) and dynamic adaptation to fluctuating electricity prices and grid conditions. Special emphasis is placed on application-oriented interfaces that connect the production level and the energy market. These interfaces allow for multi-level reaction strategies, ranging from real-time adjustments to daily and weekly planning horizons, ensuring effective demand response and load shifting.

By aligning energy consumption with market signals, reducing production costs, and improving sustainability, the developed architecture enhances the economic viability of process flexibility; exemplarily conceptualized in a joint project with industrial facilities – foundry and long production. This research underscores the transformative potential of digitalization and market-driven energy optimization in the steel industry. By demonstrating practical applications in real-world production environments, it lays the foundation for scalable solutions that balance economic efficiency with ecological responsibility.

Speaker: Benjamin Böcker (HiScience GmbH)

329 Seamless Quality Management in the Transition to Energy-Efficient Steel Production

This presentation explores how a quality execution system effectively addresses the key challenges of the "twin transition" – the shift toward both ecological and digital sustainability – making these transformations more manageable.

As steel manufacturers transition to more energy-efficient production processes and replace existing plants, maintaining consistent quality control becomes increasingly complex. In this rapid transformation, driven not only by ecological demands but also by the imperatives of digitalization, a quality execution system plays a pivotal role. Designed for flexibility, this system seamlessly adapts to changing processing routes while ensuring reliable quality management.

When processing routes and conditions change, the impact extends beyond changes of the data landscape. Rather, product flow and genealogy must be remodeled, product quality reassessed, and quality processes realigned. New causes of quality deviations must be analyzed and documented, while surface defects require evaluation and processing that exceed previous standards. A quality execution system is uniquely equipped to meet these challenges.

By integrating advanced production data warehousing, data monitoring, sophisticated surface defect analysis, automated grading mechanisms, and root cause analysis, a quality execution system enhances production accuracy, reduces rework rates, and improves overall plant efficiency. These capabilities provide manufacturers with deep quality insights, enabling them to adapt to changes in supply chains while maintaining consistent product quality – even as raw materials and energy sources shift toward more sustainable alternatives.

Speaker: Mr Thorsten Claff (SMS group)

Refractory & Equipment Maintenance

1.3.4

330 Investigations on hearth refractory and skull

The Gwangyang Blast Furnace No. 3 experienced an early relining approximately 12 years after its initial blow-in due to premature wear of copper staves leading to shell damage and damage to the hearth cooling system caused by hot metal leakage at the No.1 taphole. To expand the internal volume from 4600 m³ to 5500 m³, a complete dismantling of the furnace body was undertaken. During this period, core boring was conducted in areas where the hearth cooling system was damaged to sample the hearth refractory and skull. These samples were analyzed for their composition, conductivity, and other properties based on their location. The study results provide insights into the material degradation mechanisms and inform strategies for enhancing the durability and performance of blast furnace components.

Speaker: Jungil Kim (POSCO)

331 Blast Furnace Hearth Relines From Concept to Construction

This paper will discuss a systematic approach for the design and construction of a new hearth, employing an “inside-out” approach. A comprehensive diagnostic is first performed by reviewing thermocouple and operational data from the current campaign to determine expected process loads in the new campaign. Three-dimensional thermal models of the new hearth design are analyzed using boundary conditions developed from the diagnostic. The thermal models evaluate the performance of the hearth under normal and high process loads. The model also analyzes a “worst-case” wear situation, which evaluates the hearth refractory’s ability to cope with additional wear during rough, high productivity operations, when the furnace may also see heavy leakage of gas, water, or steam attack. An expansion model is then developed to ensure the expansion design functions as intended. Finally, recognizing that construction is a pivotal phase of the hearth reline process, this paper will examine installation methodology and other considerations to ensure a successful hearth reline.

Speaker: Mr Rudy Tolkamp

Blast Furnace Hearth Relines From Concept to Construction.pdf

332 Development of a Handheld Low-Frequency Ultrasonic System for Precise Stave Wear Measurement in Blast Furnaces

Stave wear in blast furnaces is a critical issue affecting operational efficiency and campaign longevity. Several factors influence wear severity, including furnace design, operational practices, raw material properties, and cooling performance. However, stave wear patterns are often unpredictable and irregular, making accurate monitoring essential for maintaining the integrity of the cooling system.
In 2013, we developed a low-frequency ultrasonic system capable of measuring stave thickness from the furnace shell while the furnace remained in operation. In 2019, we launched a new research and development initiative to enhance measurement accuracy, reliability, and robustness, particularly for complex wear profiles. The result is the StaveCheck™ system, a handheld Low-Frequency Pulse Ultrasonic (LFPU) device designed to penetrate thick furnace shells, variable ramming materials, and copper or cast-iron staves, achieving measurement accuracy within ±2 mm. This patented system is flexible of detecting the vertical profile of staves, which outweighs the conventional ultrasonic probe technique.
This paper details the development process, key technological advancements, and performance validation of the StaveCheck™ system, highlighting its potential for improving blast furnace maintenance and operational safety.

Speaker: Afshin Sadri (Hatch Global Director of Asset Performance Management (APM) Group)

19:00 Conference dinner

Thursday 9 October

Automation & Process Control

2.3.6

Convener: Michele De Santis (Rina Consulting - Centro Sviluppo Materiali SpA)

333 Electromechanical servo drive for mold level control: performance and evolution

Mould level stability is crucial for achieving excellent surface quality and product cleanliness in continuous casting. This article explores the evolution of the Mould Level Master, a technological package for mould level control based on an electromechanical actuator, from its initial testing to its implementation across a wide range of casting machines—including billet, bloom, and extra-wide slab casters. The system has been successfully applied not only in the steel industry but also in non-ferrous alloy production.
The Mould Level Master is a highly effective solution for upgrading existing casters, offering tailor-made implementations with minimal downtime. This article examines the performance of the electromechanical servo actuator and the control algorithms, analyzing their effectiveness in ensuring precise mould level regulation and casting stability. Its proven results across various applications make it not only an ideal tool for caster upgrades but also a state-of-the-art solution for new casting machines.

Speaker: Stefano Baf

334 Advanced Instrumentation and Holistic Process Improvement in Continuous Casting at Outokumpu Tornio

Outokumpu, a global leader in sustainable stainless steel production, has implemented advanced instrumentation in its Tornio casters to gain deeper insights into the continuous casting process and enhance product quality. The casters are equipped with molds containing optical fibers, achieving 1786 Fiber Bragg Grating (FBG) based temperature measurement points, quality prediction software, and a hot surface inspection system. This setup provides detailed information from the molds, enabling the investigation of the potential prediction of future sticker cases and other quality related events.
A holistic approach to process improvement is also presented, exemplified by the prediction of longitudinal cracks. Depressions within the mold can be detected, but whether these depressions develop into cracks is determined during strand guidance, depending on the steel grade and cooling profile. Detected depressions are combined with the results from the Steel Quality Indicator, which analyzes steel chemistry, bending and unbending processes, and the temperature history of selected surface positions for each 1-meter segment of the strand as it passes through the strand guidance. Considering all this information allows for a more comprehensive evaluation of quality issues.
Vertical fiber installation offers optimal meniscus level detection, the highest thermal resolution of the mold and is used as a tool for design of SEN, evaluate mold powder and steel flow in mold. Horizontal fiber installation can achieve higher horizontal resolution of sensing points to improve LFC detection and by using only a few rows of fibers the system is fully functioning for breakout detection using a less advanced fiber installation. At Outokumpu, both systems are installed and compared, and a method to predict meniscus behavior even with horizontal fiber installation will be presented.
This paper discusses the advanced instrumentation and holistic process improvement strategies at Outokumpu Tornio, highlighting their impact on continuous casting quality and efficiency.

Speaker: Oliver Lang (Primetals Technologies Austria)

335 Human-free casting operation. Safety and efficiency increase thanks to robotization and artificial vision

The continuous casting phase in steel production still requires several manual operations near molten steel, posing significant safety risks. This paper explores how the integration of advanced robotic technologies can fully automate casting operations, significantly improving safety, process efficiency, and overall production performance.

The study highlights the differences between various robotic applications, demonstrating how tailored solutions can meet specific production plans, even by leveraging short maintenance stops to implement automation without major disruptions. The modular adaptability of these solutions allows for step-by-step installation, ensuring seamless integration into existing processes while maintaining operational continuity.

Furthermore, the paper discusses the importance of operator training and familiarization, outlining a structured customer training program designed to facilitate a smooth transition to robotic automation and enhance user confidence in managing the new technology.

By combining automation, flexibility, and a progressive implementation approach, robotic solutions are set to redefine the future of continuous casting, making steel production safer, more efficient, and highly adaptable to industry needs.

Speaker: Mr ION RUSU (POLYTEC SPA)

336 Improved EMLI Technology for Early Slag Detection and Enhanced Steel Yield and Quality

Ladle slag carryover into the tundish has been a significant challenge in steelmaking, adversely affecting the tundish refractory material reducing its lifespan. Additionally, slag carryover compromises steel quality due to slag entrainment, which is a primary source of undesired inclusions in the final products. To achieve high-quality steel and maximize yield, it is essential to minimize slag carryover. A sensitive slag detection system is required to control the quality by controlling the movement of slide gate plates.
Among the various solutions currently exist, electromagnetic slag detectors have proven highly effective, significantly reducing the amount of slag carried into the tundish. It is mounted close to the slide gate system allowing direct measurement of the slag carry-over through the flow channel. This technology enables the production of superior-quality steel achieving notable increase in yield. As customer demands for higher yield continue to grow, there is an ongoing need to enhance the sensitivity of slag detection sensors to meet these expectations. To enable real-time and early warning of slag entrainment during the tapping process, a slag detection system with higher sensitivity, faster response and higher repeatability is required.
The present study reports the comparison in performance of the different EMLI slag detection sensors (both existing and new) at the Högänäs AB facility in Halmstad. The measurements show that the new system achieved 40 to 50% improvement in response time, with a slag detection probability exceeding 90% compared to the existing system. The next generation sensor has the potential of detecting difficult steel grades in shrouded condition improving process efficiency and product quality. In conclusion, the new sensor can further minimize slag transfer due to its improved characteristics by providing a reliable detection signal of the slag to close the gate, providing a desired balance between a higher yield and quality.

Speaker: Mr Per Johansson (Höganäs AB)

337 Safe Tundish Drain with Residual Steel Detection (RSD) for Maximized Yield and Process Optimization

Accurate and reliable measurement of the remaining steel level in the tundish is very important for preventing undetected emptying, optimizing steel grade changes, and maximizing strand length. Conventional weight-based measurement often introduce inaccuracies increasing the risk of slag carryover into the mold, unnecessary downgrading, and reduced process efficiency.
The AMEPA Residual Steel Detection (RSD) system provides a precise and reliable solution for monitoring the residual steel height in the tundish. Utilizing an electromagnetic field-based measurement principle, the RSD system directly detects the steel/slag boundary layer, enabling safe and optimized tundish drainage. Using the tundish weight signal of the load cells is an indirect measurement method, since the steel level has to be calculated based on the assumption of the composition between steel, slag and tundish powder. Therefore the RSD signal is more accurate. This results in higher yield, reduced tundish skull formation, and improved operational efficiency.
Furthermore, RSD technology is particularly beneficial during steel grade change. By safely lowering residual steel levels to a minimum before pouring a new grade, the system significantly reduces mixing zones, reaching final product quality much faster, which leads to way fewer steel downgradings. By safely draining the tundish to the optimal steel level, the system enhances reproducibility and reduces material losses, leading to cost savings and increased profitability.

Speaker: Benjamin Ruf

Digital transformation - Steel materials and their application

6.1.5

Convener: Cristian Viscardi (ECOTRE Valente srl)

338 Transparent Online Calculation of Product Carbon Footprint in Steel Industry

Reliable carbon footprint calculations and certificates for the various steel products are increasingly demanded by the market. Many approaches are based on yearly production tonnage and average CO2 equivalents. A production management system allows to track the material and energy consumptions for each piece of produced material. Thus, it is able to transparently calculate the related greenhouse gas emissions on piece and product level, along the entire production chain from raw material preparation and processing in iron and steelmaking, via hot and cold rolling to commissioning for shipment after finishing lines, i.e. from cradle-to-gate. By configuration of process characteristics impacting the product carbon footprint and corresponding greenhouse gas emission factors as well as calculation rules for the resulting emissions, the presented solution can be adapted to the granularity of available process data in a steel plant. It is possible to define different emission values for each produced material like gross values including scrapped parts of a material, net values without such scrapped parts or the resulting class of green steel according to the recently published Low Emission Steel Standard. Thereby, a steel plant can start with implementation of a product carbon footprint tracking based on mass balances and produced material weights in defined plant areas. In a next step, if relevant process data are available and considered on the level of single production steps, the accuracy of emission calculations is increased accordingly for the related product. This procedure is exemplified by the implementation of a product carbon footprint tracking at Tata Steel Netherlands within PSImetals production management system.

Keywords: Product Carbon Footprint; Cradle-to-Gate Tracking; Production Management; Decarbonization

Speaker: Dr Martin Schlautmann (PSI Software SE)

339 Multi-agent-based approach for decreasing carbon footprint of future integrated steelworks: the AgiFlex overall concept

The European Green Deal challenges the steel sector to implement breakthrough modifications to significantly decrease its carbon footprint, and European steel producers are planning consistent investments in this direction. Integrated steelworks are particularly affected since, besides production process changes, important modifications are envisaged also for gas and energy management. Injection of H2-rich gases in blast furnaces, and replacement of blast furnace-basic oxygen furnace route with direct reduction-electric arc furnace route will significantly affect the site-wide gas supply. The replacement of fossil sources implies challenges related to intermittent renewable energy and gases (e.g. green hydrogen) with consequent fluctuation in energy availability and prices. Therefore, current production and energy management schemes must be revised to enable gradual and sustainable integration of C-lean processes. The European project co-funded by the Horizon Europe programme and entitled “Agent-based models minimizing carbon usage in flexible and efficient future integrated steelworks” (AgiFlex, G.A. 101138813) develops a cutting-edge tool to fill the lack of ICT tools addressing the above-mentioned challenges. A multi-agent approach is applied for production and energy management, which is based on digital twins of production units and advanced optimized framework. Its aim is process monitoring and control and optimal process integration in terms of conditions, material and energetic resources along the whole production chain. Two industrial sites are involved for demonstration. The contribution focuses on the overall AgiFlex concept.

Speaker: Dr Ismael Matino (Scuola Superiore Sant'Anna - TeCIP Institute - ICT-COISP)

340 DynReAct – An open-source production planning software

We present the open-source planning software DynReAct, which grew out of a research project on dynamic production planning and scheduling in the steel industry. The software implements a three-stage approach to the flexible flow-shop planning problem, comprising modules for long-term, mid-term and short-term planning. Long-term planning implements an order-less planning approach based on working shifts, whereas mid-term planning is responsible for lot creation and scheduling. The short-term planning module incorporates real-time information and enables quick responses in the case of unexpected events, such as machine outages or re-prioritisations. The three planning levels are addressed by means of different optimization algorithms. DynReAct leverages so-called plant performance models for the integration of real-time plant status information into the planning process. Furthermore, it includes a module for allocation of raw materials to customer orders.
The DynReAct software comes with a set of configuration options and pluggable interfaces that enable adaptations to different use cases. A flat steel sample use case is included in the open-source package and will be used to showcase the features of the software and the interaction between the different planning levels.

Speaker: Christoph Nölle (BFI)

341 Optical Measurement of raw material particle size

The physical properties of raw material play an important role in the iron and steel making processes. Especially the grain size is important, e.g., for permeability control in the blast furnace or the densification of the sintering process.
However, current grain size measurement methods are often irregular, labor-intensive, and rely heavily on manual effort, limiting the ability to achieve real-time process optimization and potentially leading to inconsistencies in raw material characterization.
This paper presents the development and testing of smart sensors designed to automate raw material grain size measurement using existing optical sensor technologies. Our approach aims to overcome the limitations of traditional methods by providing continuous, automated, and accurate grain size data. This, in turn, enables more precise process control and improved product quality.
We explore and compare two approaches based on optical sensors.
The first approach utilizes a laser line scanner to capture highly accurate height profiles of the raw material as it moves along a conveyor belt. The sensor output is a 3D point cloud that contains the particle shapes.
The second approach employs a camera-based system coupled with advanced image analysis techniques. This method captures two-dimensional images of the material flow, which are then processed to identify and measure individual particles.
We shortly discuss the specific image processing algorithms employed. Afterwards, the approaches are compared in terms of accuracy, speed, and robustness under varying operational conditions. We present experimental results demonstrating the effectiveness of our automated measurement system and discuss its potential for integration into industrial iron and steelmaking environments. Finally, we highlight the advantages and disadvantages of each approach, offering guidance for selecting the most suitable sensor technology based on specific application requirements.

Speaker: Dr Christian Dengler (SMS group)

342 Optimized availability of a mechanical drive system through holistic predictive maintenance approach

Predictive maintenance is often seen as an add-on for predicting failures. This viewpoint limits the real-life results of predictive maintenance solutions. To truly maximize drive system availability, decisions must support this goal throughout the entire lifecycle, akin to the continuous use of smart devices for personal health monitoring.

Optimizing drive system availability begins at the project specification phase and continues until the drive package is decommissioned. This holistic approach applies to both mechanical and electrical drive technologies, ensuring that every stage contributes to the overall reliability and efficiency of the system.

This paper presents a predictive maintenance system for hot long rolling mill gearboxes, incorporating vibration and oil system sensors. The results and experiences from implementing this system are mapped within the holistic approach. The paper discusses the influence of various factors, including drive package specification, supplier assessment, purchase decision, engineering, manufacturing, assembly, testing, commissioning, operation, maintenance, and repair. Each of these stages plays a role in determination how high benefits can be reached through a predictive maintenance solution.

This paper provides valuable insights for decision-makers and offers practical guidelines for engineers to enhance drive system availability. By adopting a proactive and holistic approach, organizations can significantly improve the reliability and longevity of their mechanical drive systems, ultimately leading to increased productivity and reduced downtime.

Speaker: Mr Veikko Äikäs (SEW-EURODRIVE)

Ironmaking Cokemaking

1.1.1

343 Innovative Decarbonization Strategies: Thermal dry reforming for enhanced blast furnace efficiency

This paper presents a pioneering approach by SMS group, focusing on the integration of advanced thermal dry reforming technology into existing blast furnace infrastructures. The scope of this study is to explore the potential of Paul Wurth's thermal dry reforming process in reducing CO2 emissions while leveraging current coke oven plants. This innovative technology introduces a novel method to the industry by generating hot syngas at temperatures exceeding 1300°C. The syngas, characterized by its chemical composition, is optimized for injection into blast furnaces, thereby reducing the coke consumption rate.

The results discussed in this paper are derived from pilot plant tests conducted at a coke oven facility. These tests have demonstrated the feasibility of producing syngas suitable for blast furnace operations. The study is currently at the pilot stage, with plans for partial implementation in select integrated plants. The findings indicate significant potential for CO2 emission reduction and increased productivity within blast furnace operations.

The anticipated benefits of retrofitting this technology into existing BF-based integrated plants are substantial. By incorporating this method into the decarbonization roadmap, plants can achieve a marked decrease in carbon emissions, contributing to a more sustainable steel production process. The paper will detail the results obtained thus far and outline the expected future outcomes, emphasizing the role of this technology in the industry's transition towards greener practices.

In conclusion, this study highlights a crucial step in the decarbonization of steel production, offering a cost-effective solution that aligns with global sustainability goals.

Speaker: Cristiano Castagnola (SMS group)

344 Impact of iron source and binder type on the mechanical strength and microtexture of ferro-coke

The addition of highly reactive ferro-coke can lower the temperature of the thermal reserve zone (TRZ), which improves shaft efficiency in a blast furnace. A better understanding of the link between microstructure, microtexture and strength in ferro-coke is needed to optimise the blend composition and maximise strength.
This study investigates the microstructure and microtexture of ferro-coke using 3D micro-computed tomography (Micro-CT), and an automated reflected light microscope. The effect of iron ore and direct reduced iron (DRI made from hydrogen reduction of Australian iron ore) on the strength of ferro-coke was analysed. The impact of an Australian high fluidity coal and coal tar pitch (CTP) as binders on ferro-coke structure and strength was also investigated.
The results show that the strength of ferro-coke mostly depends on the quality of bonding between the reactive maceral derived component (RMDC) structure and inert maceral derived component (IMDC) structure. The porosity is a proxy for the thermal plasticity of the blend. The addition of iron ore without binder decreased both the porosity and strength. This was attributed to the decreased fluidity of the blend in the presence of iron oxides, resulting in poor bonding between RMDC, IMDC, and iron particles. The microtexture results showed that iron ore decreased the anisotropy. Conversely, the fluidity of the blend was preserved with DRI in the blend, thus allowing for the formation of ordered carbon structures. It was postulated that the reduction in fluidity was caused by the presence of iron ore in the oxide form and its reduction during carbonisation which promoted the oxygen cross-linking reactions. The addition of CTP improved the porosity and strength of ferro-coke regardless of the iron source. High fluidity coal did not provide sufficient binding in the presence of iron ore, however, when blended with DRI, a strong ferro-coke was formed.

Speaker: Guanghua Lu

345 Control of Low Bulk Density Region around Briquette in Briquette Blending Carbonization Process

One of the coal pre-treatment process used to produce high-strength coke while incorporating a large amount of low-quality coal is the briquette blending carbonization process. Briquette blending carbonization process improves coke strength by mixing high-density briquette with powder coal. On the other hand, it is known that blending briquettes with powder coal forms low bulk density regions around the briquettes, raising concerns about the potential decrease in coke strength. To reveal the factors that form low bulk density region around briquette, we quantitatively evaluated the low bulk density regions when briquette was blended with several powder coals. This evaluation was based on the product of the density difference from the powder coal portion and the volume. As a result, it was confirmed that the formation of the low bulk density region around briquette was affected by the distribution and moisture of powder coal portion. We then evaluated the coke strength by varying the dilatability of the briquette blended into powder coal with different quantitative values of low bulk density regions around briquette. As a result, it was confirmed that the coke strength decreased when the dilatability of the briquette was low, and a certain level of dilatability of the briquette was necessary to maintain coke strength. Additionally, it was found that smaller quantitative value of the low bulk density regions, lower the dilatability of the briquette required to maintain the coke strength. This study demonstrated that it is possible to produce high-strength coke even while lowering the dilatability of briquette by controlling and reducing the low bulk density regions around briquette.

Speaker: Mr Isao Takahashi (Process Research Laboratories, Nippon Steel Corporation)

346 Adapting to age: Upgrading Coke Oven Machines for sustainable plant longevity

In today's rapidly evolving industrial landscape, coke oven plant operators are increasingly confronted with the pressing challenge of managing aging equipment. As many coke oven batteries, machines, and associated equipment near the end of their operational lifespan, operators face the risk of unscheduled production interruptions, increased emissions, and elevated health and safety concerns for workers.

This paper aims to illuminate the path forward by showcasing a selection of recent projects that have successfully tackled a few of these challenges. We will explore cutting-edge technologies and innovative design enhancements that are transforming coke oven machines and their ancillary equipment. Moreover, we will introduce advanced tools that empower plant operators with real-time data and insights, enabling them to proactively extend the longevity of their equipment and optimize operations.

Speaker: Mr Gabriel Korkmaz (SMS group)

347 Influence of HDPE addition on microstructure transformation during coking of Australian coking coals

The partial substitution of coal with waste plastics in the coking process can improve resource recycling and sustainability of cokemaking and ironmaking processes. A fundamental understanding of how plastic pyrolysis influences microstructural transformations in coke ovens remains limited, despite its significant impact on coke quality. This study addresses this knowledge gap through an interrupted plastic layer sampling technique and Synchrotron micro-CT 3D image analysis.
Representative Australian mid-rank coking coals with varying fluidity and maceral compositions were blended with recycled high-density polyethylene (HDPE) granules (3-4 mm) at a 5% ratio, a common waste plastic in Australian domestic waste streams. A lab-scale double-wall coke oven was used to prepare coke-forming layer (CFL) samples through interrupted coking tests, which included characteristic layered structures formed under practical coking conditions. Synchrotron micro-CT was utilized to scan the CFL samples to examine the impacts of HDPE addition on microstructural transitions.
Overall, the addition of 5% HDPE decreased porosity in the intermediate CFLs but increased porosity in the semi-coke and coke regions. HDPE acted as a binder, forming a HDPE-coal mixture while hindering CFL formation. Voids generated by plastic devolatilization were insufficiently filled, leading to increased porosity in the later semi-coke stage and the final coke structure. The increased coke porosity with HDPE addition appeared to be related to the coke reactivity index (CRI), likely due to the higher diffusivity of CO₂. Notably, coal with higher fluidity and vitrinite content exhibited greater increases in porosity, mean pore size, and pore wall thickness during the resolidification and semi-coke stages, while showing minimal changes in the coke quality. This can be attributed to its inherent thermoplastic properties, which extend the overall transformation and enhance its resilience to the HDPE addition effect. Consequently, coals with higher vitrinite content and fluidity may improve the carrying capacity of HDPE in cokemaking.

Speaker: Mr Jangho Jo (University of Newcastle)

Process Monitoring & Quality Control

2.2.7

Convener: Mauro Bianchi Ferri (Acciarium)

348 Developments of monitoring of Billets quality through modelling and new sensors in the frame of Sunshine project

The quality of the products in bar and wire rods production is strongly affected by the quality results in Continuous Casting both for conventional and special steels.
In different ways Feralpi Groups is working to improve the billets quality in terms of surface, internal and shape defects also with activities included in the R&D projects coupling new equipments, new sensors, studies and data analysis.
In particular Starting since 2024 the project sunshine is active CoFinanced by RFCS (Reasearch Fund For Coal and Steel) devoted to application of mathematical modelling of the solidification coupled with new sensor for billets conditions measurement and data analysis to be able to evaluate the eventual causes of events of quality variation.
Thanks to this approach Feralpi Siderurgica is now adopting new measurement systems to alert in case of abnormal billets conditions also devoted to the subsequent stage of rolling in case of action necessary.
Furthermore the studies and new applications in the frame of the project are used to gain know how for the process technologist and for the technical departments also thanks to the collaboration with new partners and technology providers.
In this way the systems applied aim to cover both the present and the future necessities and quality constrains.

Speaker: Piero Frittella (FERALPI SIDERURGICA)

349 Effect of Bottom-Blowing on Nitrogen Removal Kinetics in Electric Arc Furnace (EAF) Conditions

The growing automobile market is expected to drive demand for high-strength exterior panels and electrical steel sheets for motors. These products require precise impurity control to maintain formability and magnetic properties. Nitrogen is a particularly crucial element in determining the mechanical properties of steel. Although higher nitrogen content improves tensile and yield strengths, it reduces elongation, negatively impacting formability. However, in the electric arc furnace (EAF) process, nitrogen from the atmosphere dissolves into the molten steel during melting. This issue arises from the nature of the EAF process, where raw materials are melted using arc heat in an atmospheric environment. Due to these challenges, nitrogen control is typically performed during secondary refining processes such as Vacuum Degassing (VD) and Ruhrstahl-Heraeus (RH) degasser. Recently, several studies have focused on utilizing bottom-blowing technology within the EAF process to effectively remove nitrogen from molten steel. Furthermore, with the increasing adoption of hydrogen-reduced DRI (H2-DRI) in the EAF process as part of the transition to environmentally friendly steelmaking, new challenges in nitrogen removal are emerging. H2-DRI has an extremely low carbon content, leading to insufficient CO gas generation during melting. In traditional EAF processes, CO gas, generated from the reaction between FeO and carbon, plays a crucial role in promoting nitrogen removal. However, as the usage of H2-DRI increases, the lack of a carbon source reduces CO gas formation, thus diminishing the nitrogen removal efficiency. Therefore, the present study aims to investigate the efficiency of nitrogen removal through bottom-blowing in EAF operating conditions. Specifically, the current study examines the effects of injecting Ar/CO2/CO gas mixture as well as carbon content in molten steel on nitrogen removal kinetics.

Speaker: GeunWoo Byun (Hanyang University)

350 Advanced EAF Optimization Strategies Using Intelligent Tenova Technologies

For more than two decades, off-gas analysis technology has been used worldwide, initially as an engineering tool for the design and tuning of fume systems and later as a key tool for EAF chemical energy optimization. In later years, the off-gas analysis has been used for full EAF dynamic control that addresses scrap variability that does not allow for simple EAF profiling operations. Today, with the issue of raw material variability, EAF steelmakers have a new challenge in relation to reducing CO2 emissions, as well as finding options to continue optimizing the process without compromising product quality, while reducing operating cost in a safe operating environment.
Tenova's "intelligent" EAF (i EAF®) technology uses off-gas analytical data and advanced software techniques based on Artificial intelligence (“AI”) principals such as robustness, security and safety to implement full dynamic control of the EAF process, providing the functionality needed for the modern EAF steel plant. The i EAF® closes the mass and energy balance in real-time, determining the actual net energy received by the charge after energy losses and uses the net energy for real-time control of the electrical and chemical energy sources. The iEAF® uses the NextGen, a state-of-the-art analyser that utilizes laser technology that requires minimum maintenance with no calibration and with a fast response with delay time under ten seconds.
This paper will present an overview of the i EAF® system, together with Tenova's optimization strategy, steps to reduce emissions and the latest proven results.

Speaker: Mr Vittorio Scipolo (Tenova Goodfellow Inc.)

Process Optimization & Control

6.1.2

Convener: Luca Piedimonte (Ori Martin)

351 Energy-efficient production based on a comprehensive scheduling including an optimized temperature guidance and heat pacing

ArcelorMittal Eisenhüttenstadt und Smart Steel Technologies bundled forces to establish an optimized temperature guidance in the ArcelorMittal Eisenhüttenstadt meltshop. The underlying core of the supporting models, namely the Ladle Furnace, LF Temperature or Secondary Metallurgy Exit Temperature Model is a digital twin of the whole meltshop. It incorporates all heats and different steel grades, the different ladles in circulation and all aggregates in the meltshop from Basic Oxygen Furnace, BOF, via Argon Stand and Degassing Statio, RH to the caster. All relevant planned and actual timestamps of all heats on their way through the meltshop as well as important process parameters are transferred via Message Queues from the L2 to the model databases. All heats including their temperatures are exactly tracked. Understanding and implementing the material flow in the meltshop including eventual disturbances and delays is crucial to build a digital twin. It is used to exactly model and recommend the hand-over temperature from secondary metallurgy to the continuous caster. The result is a precise temperature and thus, time structure for a smooth high quality production. Further, this optimization is an integral part of the newly to be installed scheduling system, the SST Scheduler. It dynamically ingests the current situation in the meltshop and recalculates the production schedule. Only this comprehensive approach enables a steel plant to exactly plan all start and ends for the individual production steps. A modern dynamic scheduling system considers both a precise timing for an energy efficient production and smooth process flow to fulfill all quality demands and delivery dates.

Speakers: Mr Jens Gellert (ArcelorMittal Eisenhüttenstadt), Dr Otmar Jannasch (Smart Steel Technologies GmbH)

352 A continuous flow model for long-term production scheduling and reactive replanning.

In the steel industry, most companies operate in a competitive national and international market, with prices determined by competition. To enhance profits, firms must focus on reducing production and commercial costs. Those unable to adapt their strategies may lose their competitive edge. Effective scheduling of resources is crucial to achieving goals such as increasing production and minimising completion time. However, most scheduling problems are NP-hard, meaning their solutions become exponentially complex with size. Production scheduling in the steel industry is particularly challenging due to multiple production steps, resource requirements, and potential disruptions, such as breakdowns and order cancellations. This paper presents a continuous flow model approach for long-term production scheduling that is efficient to solve. It can calculate an approximate time for the production schedule over one month. It can also determine the material mix needed to fulfil the production targets, and it is so fast that, as soon as the situation in the factory changes, a new plan can be calculated reactively.

Speaker: Andreas Wolff (VDEh-Betriebsforschungsinstiut)

353 Case study on product quality management on a continuous galvanizing line thanks to digital solution

Fives’ Eyeron® is a digital solution aiming at managing the quality of steel products in real time. This solution can be deployed either on a single asset or in a fully integrated plant. Thanks to its effective data injection and powerful rules engine system, it can automatically provide precise quality grading and reports, and issue recommendations for order reallocation or repair of any type of steel product.
Installation of this digital solution was successfully completed on the Continuous Galvanizing Line n°4 of Marcegaglia Ravenna SpA plant based on a strong partnership between steelmaker quality department and Fives.
This paper will present the following results observed after a test period of few months:
• Enhanced Reliability in Quality Control: Ensures a significant increase in the reliability of quality control across all product characteristics, including dimensions, surface appearance, mechanical and chemical properties.
• Comprehensive Process Monitoring: Improves process reliability by continuously evaluating key parameters to maintain optimal performance and compliance.
• Proactive Approach with Smart Alerts: Implements a proactive strategy through an advanced alert system that notifies process operators of minor deviations before they escalate into non-conformities.
• Corrective Action Guidance: The system not only identifies potential quality issues but also suggests corrective actions to quickly resolve them, minimizing disruptions.
• Reduction in Non-Conformities and Disputes: Significantly decreases internal non-conformities and customer claim by ensuring consistent product quality and early detection of deviations.
• Advanced Deep Failure Analysis: This system will enable the implementation of deep failure analysis using advanced machine learning algorithms to further enhance quality assurance and predictive maintenance.
This innovative software optimizes quality control efficiency, reduces operational risks, and enhances overall product reliability.
Based on presented successful results, Marcegaglia Ravenna SpA intends to upscale Eyeron® on full Ravenna cold rolling plant.

Speaker: Maxime Monnoyer (Fives KEODS)

354 The use of image data in steelmaking – a short guide to promises and pitfalls

Images are a very powerful tool in monitoring complex processes in industrial settings and indicating relevant events with impact on process quality and stability. The intuitive interpretability of an image is often superior to the extraction of numerical key performance indicators based on multiple data streams from a variety of sensors, but not every relevant process aspect can be directly monitored in form of images, and not every image data stream can receive attention from an operator with the right process experience. Therefore, automatized image processing methods for process surveillance, optimization and control are in high demand. The key challenges for successful image-based process monitoring in the steelmaking industry are inaccessible environments with often rough conditions, high demands on the timing of data acquisition and analyses, and the complex interplay of many factors influencing an outcome of a process. Even after a successful development of image acquisition solutions, the obtained data needs to be evaluated sensibly, and correct conclusions need to be drawn for the process, which might involve further knowledge from process models or experience.
In this contribution, we discuss these important challenges on the example of three instances of image data analysis in steelmaking: the prediction of scrap content and composition on trucks via a combination of optical and LIBS sensors, the evaluation of converter vessel wear based on thermal image acquisition and combination with finite element wear simulations, and the assessment of stirring efficiency and homogenization degree in a Ruhrstahl-Heraeus degassing plant through the combination of image data and multiphase fluid simulations.
Discussing these use cases, we will describe where and how image data can be successfully employed to improve key aspects of industrial processes, what needs to be observed, and which impact can be achieved through these measures.

Speaker: Christine Gruber (K1-MET)

355 Global-Local Order Dressing: How Steel Producers Can Use Product Configuration and Rule-Based Engines to Generate Production Orders

Quality specifications are crucial for the metals industry to ensure consistent quality and safety. Integrating these specifications into the manufacturing execution system (MES) is essential for maintaining expected quality levels, minimizing errors, and enhancing efficiency, thereby meeting regulatory requirements and customer expectations. However, metals producers with geographically distributed locations face challenges in ensuring compliance with international quality standards, such as inconsistent data representation across different systems and varying completeness levels. Addressing these challenges requires a robust strategy that includes effective communication, standardized processes, and advanced technology integration. Our presentation will introduce how Global-Local Order Dressing serves as a central knowledge base for the steel industry, enabling producers to leverage a unified quality repository with local download capabilities. As part of the digital transformation journey which is required for process optimization, the solution provides instant access to centralized industry specifications, reducing time-consuming and error-prone data entry at each local instance, allowing quality assurance teams to focus on core tasks and enhance productivity. We will further show how regardless of the location, the solution ensures that all teams adhere to the same best practices, resulting in consistent and high-quality outputs.

Keywords: Order Dressing; Quality; Global; Local; Efficiency; Quality Standards

Speaker: Marc Schwarzer (PSI Software SE)

Quality Control & Inspection

3.1.4

Convener: Giordano Streghi Montauti

356 A Study on reducing the dispersion of the mechanical properties of hot coils through the dynamic adjustment of the coiling temperature

The mechanical properties are the most basic quality of the hot strip products. Normally, the mechanical properties are gained with the design of chemical composition and the control of the process factors such as finish rolling delivery temperature (FDT), strip speed, cooling rate, coiling temperature (CT), and so on. These factors are not dynamically adjusted in the conventional system, and we should frequently change them based on the result of the statistical analysis in case the defect happens continually. However, there is a steel grade with the dispersed mechanical properties. In this case, it is not easy to improve the defect with the conventional method.

In this study, thus, we devise how to adjust the coiling temperature dynamically in order to reduce the dispersion of the mechanical properties. Throughout the big data method, we first derived a prediction model utilizing various factors including chemical compositions, temperatures, specific heat, and so on. In the middle of the rolling, the mechanical properties are predicted with the derived prediction model and the actual values. Then, it is determined how much the CT should be adjusted to meet the mechanical property requirement. In hot rolling, the prediction accuracy must be not high compared with that in cold rolling. However, it is shown that through the dynamic adjustment of the CT, the dispersion of the mechanical properties can be reduced and it can contribute to improve the defect.

Speaker: SangYoung Lee

357 Advancing Online, Continuous Surface Cleanliness Monitoring with the TST.1 System

The TST.1 is a practical, simple, non-contact series of systems for continuous, online monitoring of surface contamination loads on moving metal sheet. Designed for real-time process control, the system assesses surface cleanliness before and after cleaning sections in metallic coating and continuous annealing sheet finishing lines, enabling producers to optimize incoming cold-rolled steel processing and cleaning section performance.
Utilizing a laser ablation (LA) technique, the TST.1 stimulates surface contaminants to generate a measurable signal, providing instant contamination data. The system operates at a large stand-off distance, ensuring safe and easy deployment while remaining effective on unstable sheets and in any orientation. The TST.1 is available in two configurations: the TST.1d, is a portable system for temporary diagnostics, troubleshooting, and cleaning section audits, and the TST.1RS, a continuous-use, permanently installed system for real-time monitoring in industrial environments. Both configurations are use “retina-safe” lasers to minimize risk for workers.
This presentation will provide a technical overview of the TST.1 system’s capabilities, along with an in-depth discussion of the engineering challenges involved in sourcing suitable lasers and designing support systems to ensure long-term laser reliability in harsh steel plant conditions. Additionally, real-world case studies from production environments will demonstrate the effectiveness and impact of the system in improving process control and ensuring coating quality.

Speaker: Mr Eric Almquist (StarTool)

358 Laser ultrasonics for microstructure verification of heat treatments and thermal processes (LUMHEAT)

Metal microstructure can be determined in situ using laser ultrasound (LUS) measurements. As a non-contact, nondestructive measurement, this can be integrated at many positions in the steelmaking process, including measurement of hot and moving samples. Swerim has previously demonstrated the application of this technology as an on-line grain size gauge installed at the SSAB Borlänge hot strip mill [1].

The LUMHEAT project is a feasibility study within the program “Impact Innovation Metals & Minerals”. The aim is to investigate how thermal and thermomechanical processes in the steel industry can benefit from the novel LUS based microstructure sensor. Several case studies are discussed, based on thermal and thermomechanical processes performed at Nordic plate, bar and strip mills. For each case the measurement conditions, observables of interest, and expected benefit of added data are considered.

The LUS microstructure gauge has also been redesigned to improve the optical working distance, simplifying placement and use of the gauge. This is expected to benefit not only the stated cases but also future measurements at other sites.

Speaker: Hampus Wikmark Kreuger (Swerim AB)

359 New Optical Flatness Measurement by Magnetic Deflection

The magnetic flatness measurement system enables precise flatness assessment of strip steel, even under high tension, where traditional optical methods fail due to elastic elongation. Unlike conventional flatness measuring rollers, which are costly and offer limited resolution, this system applies a uniform electromagnetic force perpendicular to the strip, inducing a controlled deflection that correlates with local tension. The deflection is measured optically using a Camera Cluster System (CCS) based on laser triangulation.

A production-ready prototype, installed in 2024, successfully measured materials up to 1400 mm wide. The system demonstrated high accuracy in distinguishing different flatness profiles, including sharp edge elongations and uniformly flat materials. To verify its precision, the measurement results were visually confirmed on a flatness inspection table. The system could reliably predict the flatness of each sample, which is manually inspected after every produced strip, proving its effectiveness in real-world production environments.

A key advantage of the system is that it not only detects flatness defects but also confirms the presence of truly flat material—a critical factor for quality assurance and process optimization. Unlike traditional methods that focus solely on defect detection, this system provides a continuous full-strip assessment, ensuring a more comprehensive flatness evaluation.

Additionally, its non-contact operation reduces wear and maintenance compared to mechanical systems, making it a cost-effective and scalable solution. By integrating the system into production lines, manufacturers can achieve real-time flatness classification, optimize upstream processes, and improve overall product quality. This innovative approach enhances industrial flatness measurement, reduces material waste, and ensures higher precision in steel processing.

Speaker: Mr Marian Rogge (IMS Messsysteme GmbH)

360 Enhancing quality control for Long Products with robotics and computer vision

Steel production necessitates continuous quality monitoring throughout the process. Historically, the steel industry has lagged in adopting certain technological advancements due to its harsh production environment, resulting in lower efficiency and higher risks for workers who perform many operations manually. This study shows the latest developments in the long products quality control, with the implementation of an automated system for some operations, which currently exposes operators to significant danger, like cutting and removing material samples from rods and long products on the cooling bed or measuring laminated surface quality in rolling mill. By automating this task, we aim to enhance production efficiency and improve worker safety.

Speaker: ION RUSU (POLYTEC SPA)

Waste Utilization & Carbon Capture and Utilization

5.2.4

361 FILTRABIT-NEW INNOVATION TO INDUSTRIAL DUST EXTRACTION

This paper presents the development and commercialization of a novel dust extraction technology. Driven by stringent EU emission regulations, the need for more efficient dust removal solutions has become paramount in industries like mining and metallurgy. By combining fundamental fluid dynamics research with industrial practice, SSAB researchers and Oulu University developed a modular dust extraction unit capable of significantly reducing emissions. This innovation, initially supported by EU-Horizon funding, has led to the creation of a spin-off company offering the technology to various industries. The paper outlines the innovation journey, including the theoretical underpinnings, prototype development, and successful field testing. The new dust removal method offers a promising solution to address environmental concerns and improve working conditions in industrial settings.

Speakers: Mr Jyri Tolonen, Dr Kim Fagerlund

362 Green Steel strategy and circular economy at Swiss Steel Group

Steelmaking in Europe is in transition, stepping away from the traditional blast furnace route towards electric arc furnace steelmaking. This conversion is driven by available green Hydrogen as well as by affordable electrical energy which will both become prerequisite.
Swiss Steel Group employs EAF technology in all of its 5 steel plants, enjoying a low CO2 footprint already today. As an early industry mover, a roadmap to a further decarbonization is very ambitious and will be outlined in this paper. The challenges towards a CO2 footprint reduction are described, as are the opportunities and a favorable jurisdiction which could help drive our decrabonization efforts.

Speaker: Mr Olivier Lebrun (Swiss Steel Group)

363 Modular hybrid technology in the steel plant production

The steel industry is a cornerstone of the European economy, contributing 6.7% of global crude steel production (126.3 Mt in 2023). However, it is also a major source of greenhouse gas emissions, accounting for 4% of total EU emissions and 23% of those from manufacturing industries. Achieving carbon neutrality in this high-energy-intensity sector requires innovative solutions to reduce dependency on fossil fuels.
The MODIPLANT project addresses this challenge by proposing renewable energy source (RES) based electrification of key downstream steel production processes. Specifically, the project focuses on decarbonizing reheating processes while maintaining high product quality, productivity, and economic viability. Two advanced technologies are being developed and tested. RES induction heating: an hybrid heating system will replace natural gas burners in hot dip galvanizing lines for steel coils at Marcegaglia's industrial plant. A novel electrical heating system for billets will be prototyped at Feralpi Siderurgica.
Both technologies are supported by comprehensive metallurgical studies to ensure product quality is maintained or improved. These studies encompassed tests performed on a magnetic induction pilot line, conduction heating pilot line, and Gleeble simulations. Furthermore, advanced simulations were conducted to model heating processes and predict metallurgical outcomes, and these were validated through experimental tests. This combined approach of simulation and experimental validation enhances the reliability of the proposed methodologies.
These innovations aim to demonstrate the feasibility of decarbonizing energy-intensive steel production processes, creating a pathway for industrial-scale adoption of RES technologies. The results will provide a critical step toward the EU's transition to a carbon-neutral economy, aligning with the New Industrial Strategy for Europe and addressing the pressing need for green steel production.

The project has received funding from the European Union’s Research Fund and Coal and Steel under grant agreement N. 101099118.

Speaker: Matteo Gili (RINA-CSM)

364 Sustainable Carbon Solutions for CO2 Mitigation in the Metallurgical Industry

The increasing need for steel has rised the consumption of metcoke where in Europe 45 million tons of metcoke are used annually in steelmaking processes. In the attempt for green transition, this growing need is accelerating the search for sustainable alternatives to fossil carbon products.

Pyrolysis of wood pellets from pine and spruce at temperatures above 500°C has proven effective in producing biocarbon suitable for various metallurgical applications. This biocarbon can be further processed using several agglomeration techniques to produce briquettes and pellets, optimizing its integration into specific applications. However, as competition for biomass intensifies across multiple industrial sectors, there is growing interest in alternative feedstocks, such as end-of-life (EOL) tyres, recovering substantial amounts of carbon black.

Biocarbon has been successfully tested and implemented in several types of furnaces, including electric arc furnaces (EAF), submerged arc furnaces (SAF), cupola furnaces, and induction furnaces, as charge carbon, injection carbon, and recarburizers. The implementation typically begins with partial substitution of fossil carbon with biocarbon, and studies have shown that this substitution is feasible and, in some cases, enhances process efficiency. Pyrolyzed EOL tyre char has proven a high potential for slag foaming during carbon injection in EAFs, while simultaneously contributing to a circular economy by closing the loop in waste management.

Scaling up biocarbon production depends on factors such as pyrolysis yield, economic viability, energy requirements, and raw material costs. Utilizing pyrolysis by-products such as oil and gas is essential for ensuring the economic feasibility and market competitiveness of biocarbon in the metallurgical industry.

Speaker: Konstantinos Rigas

Conversion and refining process

2.1.3

Convener: Mauro Bianchi Ferri (Acciarium)

365 Latest Startups and Technology Features for Stainless Steel Production via AOD in Europe

Cost competitiveness, high productivity and safety are crucial for the survival of the stainless steel industry in Europe. The AOD converter, as an efficient refining aggregate, is a fixed process step in every high-performance stainless steel production. Primetals Technologies is continuously optimizing and improving the AOD process, the AOD equipment and its automation.
One key innovation is the Vaicon Autofix, a fully automatic vessel suspension that eliminates manual interaction during vessel exchange. The Vaicon Autofix is combined with an air-cooled trunnion ring and increases operational safety and reduces vessel exchange time, thus enhancing plant productivity. Additionally, modern AOD converters are equipped with the Vaicon Drive Damper, which reduces vibration-induced wear, lowers maintenance costs, and prolongs equipment lifespan. An advanced dedusting system, featuring a heat exchanger, enhances energy efficiency and meets strict emission standards, improving workplace conditions.
Another recent innovation that allows to reduce operating costs is a compressed air station installed at the AOD to supply high-pressure air as a substitute for oxygen and nitrogen, reducing OPEX through decreased oxygen and nitrogen consumption.
For improved process control the AOD Optimizer, a Level 2 system that optimizes stainless steelmaking through dynamic control, process visualization, and comprehensive heat tracking was enhanced. The optimizer now features new functions for the highest process accuracy and serves as a valuable tool for process optimization during daily production. Additionally, new evaluation packages for the AOD converter in the Asset Life Expert (ALEX) condition monitoring system were developed.
Primetals Technologies has recently revamped and upgraded three AOD converters in Europe: one at ASO next and two at Aperam. In addition, a complete new line at Aperam in Genk where these features are implemented, was recently started up. This paper will present the technical highlights and operational improvements achieved with the new features developed in the latest installations.

Speaker: Bernhard Voraberger (Primetals Technologies)

366 Zinc flexible RecoDust process

The RecoDust process is an innovative pyrometallurgical technique designed for the efficient separation of iron and zinc from steel mill dust, a byproduct of steel production. This process addresses the growing demand for sustainable resource recovery in the metallurgical industry, offering an environmentally friendly and economically viable solution for the recycling of valuable metals. Unlike conventional methods, the RecoDust process relies exclusively on gaseous reducing agents, eliminating the need for solid carbon-based reductants and reducing carbon emissions.
Steel mill dust, containing significant amounts of zinc and iron oxides, is introduced into the so-called Flash-Reactor. Gaseous reducing agents, such as hydrogen or natural gas, are injected into the system, selectively reducing zinc oxide to metallic zinc vapour while leaving iron oxides largely unaffected. The zinc vapor is then condensed and collected separately, allowing for the recovery of high-purity zinc. The remaining iron-oxide-rich fraction is called RecoDust slag, this can be reintegrated into the steel production cycle, contributing to a circular economy within the metallurgical sector.
This process offers several advantages over traditional recycling methods. The use of gaseous reductants enhances process control and improves energy efficiency. Additionally, the RecoDust process supports the decarbonization efforts of the steel industry by reducing the reliance on fossil fuels and lowering greenhouse gas emissions.
Trials with the RecoDust pilot plant, which is located at the Chair of Thermal Processing Technology, have proven the technology with a input of up to 250 kg per batch and a dosing rate up to 300 kg/h. The results show a high separation of zinc using different kinds of dusty feedstocks which allows the reuse of both products of the RecoDust process.
In the future within the ReMFra project (Grant agreement ID: 101058362) further trials with dusts from EAF and the HIsarna process will be tested.

Speaker: Wolfgang Reiter (K1-MET GmbH)

10:10 coffee break

Advanced Materials & Special Applications

3.1.5

Convener: Andreas Kern (thyssenkrupp Steel Europe)

367 Enhancing rail performances: the Danieli RH2 - Rail Head Hardening process

In recent decades, the rail transportation sector has undergone continuous progress. The increasing demands in rail transportation are particularly driven by higher train speeds and greater axle loads due to heavier cargo. To meet market demands, rail producers are improving rail strength to develop high-performance rails, particularly in terms of wear resistance. Head-hardened rails offer greater resistance to wear caused by faster, more frequent trains carrying heavier loads. Additionally, the head hardening process significantly improves the fatigue life of rails.
Building on this, the innovative Danieli RH2 - Rail Head Hardening process has been specifically designed and optimized since 2008. The RH2 process involves immersing the rail head in a tank filled with a water-based polymer solution immediately after rolling. This quenchant solution enables a wide range of cooling rates, spanning from those typical of oil to those of water, thereby adapting the cooling process to each specific rail grade, from pearlitic to bainitic.
To ensure optimal conditions and consistency, auxiliary systems regulate temperature, flow rate, solution concentration, and cleanliness, preventing mold and bacterial growth. High-quality rails produced using the Danieli RH2 system have the lowest possible transformation costs and minimal environmental impact in terms of CO₂ footprint.
Accurate measurements of metallurgical and mechanical properties have been conducted on RH2-treated rails over the past five years of industrial production. Results demonstrate the RH2 system’s ability to exceed the most demanding global requirements. The foot residual stress is half the European limit. A high level of hardness uniformity can be achieved at the rail head. Consequently, the mechanical properties are more uniform, and the fatigue resistance is twice as high as the European standard requirement.

Speaker: Mr Andrea Palma (Danieli & C. Officine Meccaniche S.p.A.)

368 From Quantity to Quality: Evolving Wire Rod Production to Meet Modern Market Demands with SMS group

SMS group recently celebrated 150 years as one of the world leaders in the construction of equipment for the ferrous and non-ferrous metals industries. This paper will focus on the recent technology developments dedicated to the wire rod producers such as:
• Single-pass driven MEERdrive® finishing blocks
• Rapid production change and precise finishing through MEERdrive®PLUS high-speed finishing/sizing block
• Low temperature rolling multiloop process
• Latest generation laying heads
• 3-fan 3-dimensional LCC® Loop Cooling Conveyor
• Rotary distributor with combined lowering device and shear
• Electric based coli compacting systems
Enhanced automation and integrated CCT® 4.0 system for advanced control

Speaker: David Maurizo (SMS Group)

369 MetConZero: Metallurgical Consequences of Zero Carbon Steelmaking

The primary challenge in steel production today is the reduction of its carbon footprint. To address this, steel producers are increasingly relying on scraps. However, residual elements in post-consumer scrap—such as copper, tin, antimony, nickel, or molybdenum—can degrade steel properties, particularly for advanced high-strength steels. The project MetConZero investigates how these residuals interact in four steel grades—Interstitial Free, Dual Phase, High Strength Low Alloy, and High Carbon—using a broad range of compositions reflecting current and future scrap integration.

The project aims to assess mechanical properties using advanced techniques, including the determination of toughness via the Essential Work of Fracture. Additionally, a novel combinatorial method will be employed to produce samples with chemical gradients to study residuals’ effects on recrystallization. Also, solid solution, precipitation, and segregation effects will be characterized using state-of-the-art techniques. The collected dataset will be analyzed with machine learning methods to identify and model key influences of these residuals.

Anticipated outcomes include practical guidelines for managing residuals in scrap-based steelmaking, alongside integration into tools like StripCam and ToughSteel. These will optimize scrap utilization without compromising quality, supporting carbon-neutral steel production aligned with European decarbonization targets.

Speaker: Mr Robrecht Jennen (CRM Group)

370 New, future ready production network for non grain oriented electrical steel

thyssenkrupp Steel Europe (tkSE) strives to sustainably strengthen its position in the global market through technology and quality leadership by optimally meeting the demand of its customers for low tolerances as well as thinner and wider products. Investments are made at tkSE along the entire production network especially for non grain oriented electrical steel (NO) in order to shape the future of the fast growing e-mobility market. It is our goal to therefore enhance the production network to produce premium e-mobility NO grades with greater efficiency.

In Duisburg, the continuous casting line 1 is replaced by the modern continuous casting line 3. The existing casting rolling plant will be split into the new continuous casting line 4 with a direct connection to the new hot strip mill 4 that can produce a strip thickness of 1.2 to 9.0 mm and widths up to 1.600 mm. One of the aims is to focus hot strip production on the Duisburg site. We are furthermore creating a competence center for e-mobility in Bochum. We built a double reversing cold mill which can produce NO material with a minimal strip thickness of 0.2 mm. An additional enhancement of the e-mobility competence is achieved by the construction of a new annealing and coating line. It is designed to processes NO electrical steel with widths up to 1.350 mm and thicknesses of 0.20 to 1.00 mm. In the next step also a finishing line will be installed in Bochum.

With this investments thyssenkrupp Steel Europe is focused on future customer requirements for highly siliconized, thin NO electrical steel grades that are used in the field of e-mobility. The new facilities will result in various benefits, particularly for our customers thanks to higher product quality, production reliability and expanded capacities for demanding e-mobility grades.

Speaker: Fabian Schongen

371 Green DUE: Fossil-free casting and rolling technology for high quality automotive exposed panels

QSP-DUE is moving forward: from a breakthrough plant concept to a consolidated technology capable of reaching production targets exceeding 4.0 MTPY of fossil-free hot rolled strips for the most demanding applications, from commodity grades to AHSS, API line pipes and automotive exposed panels.
Although QSP-DUE is a green technology by design, the introduction of the fully electric Tunnel Furnace aims to bring direct emissions down to zero, contributing to the decarbonization of the industry.
The combination of technical features and process design conceived to achieve defect-free surface, will allow the production of top-quality automotive grades for exposed and un-exposed applications.

Speaker: Mr Riccardo Conte (Danieli & C. Officine Meccaniche S.p.A.)

Automation & Process Control

2.3.6

Convener: Michele De Santis (Rina Consulting - Centro Sviluppo Materiali SpA)

372 A customizable robotic for maintaining the ladle sliding gate

This paper presents a robotic cell specifically designed for steel shop operations, assisting operators in the inspection, cleaning, and replacement of refractory components in the ladle sliding gate. This critical system enables the controlled opening of the ladle bottom, allowing molten steel to flow into the tundish of the continuous caster.

The developed robotic cell represents an innovative approach to creating a collaborative environment, where technicians and robots interact in a safe and ergonomic manner. The system automates the most strenuous and hazardous tasks, while enhancing the operators' ability to monitor and control the entire process through an advanced vision system and smart human-machine interface.

Successfully installed and tested in an Italian integrated steelworks, this solution improves worker health and safety, while ensuring higher operational quality, precision, and repeatability compared to traditional manual procedures.

Speaker: ION RUSU (POLYTEC SPA)

373 Ultrasonic steel level control: focus on performances and operability based on case study

The steel industry is increasingly seeking reliable and efficient solutions for steel level control that eliminate the need for radioactive sources. In response to this demand, Ergolines has developed an innovative technology that is gaining significant traction in the market, as evidenced by the growing number of installations worldwide. This paper presents a detailed case study showcasing the advantages of this solution in terms of measurement accuracy, operational efficiency, and overall cost-effectiveness. Specifically, the study highlights improvements in performance, reductions in operational time, and optimization of workforce utilization. By eliminating regulatory constraints and safety concerns associated with traditional radioactive-based systems, this technology offers a sustainable and future-proof alternative for steel manufacturing processes. The findings contribute to the ongoing discussion on modernizing steel production through advanced, non-radioactive measurement technologies, ultimately enhancing process reliability and economic efficiency.

Speaker: Simone Cicutto (Ergolines Lab s.r.l. - Trieste)

374 High Performance Maintenance and Repair for Continuous Casting Machines

Primetals Technologies offer extensive metallurgical and machinery service expertise throughout the entire lifecycle of steel production plants, providing a wide range of solutions to support every operational phase in steel plants and rolling mills. These solutions include service contracts, spare and wear parts service, metallurgical consulting, engineering, technological upgrades and comprehensive outsourced online and offline maintenance based on performance-based price-perton contracts. By outsourcing plant maintenance, e.g. for Continuous Casting Machines (CCM), with advanced testing equipment and electronically controlled lifecycle systems, along with welltrained personnel, clients can focus on achieving optimal product quality and high production availability. Over the past 15 years (2009-2024), Primetals Technologies Brazil has successfully managed such a contract at the Ternium Brazil CCM Plant. A new 10-year performance-based contract was awarded in April 2024, extending the partnership until March 2034. Primetals Technologies Brazil has been renowned for these contracts already since 2002, with another notable long-term partnership at the CSN CCM plant. Globally Primetals Technologies has operative contracts also in USA, Mexico, India and China. This paper provides many of the features, why and how those contracts assure benefits for both sides.

Speaker: Michael Weinzinger

375 On the application of FEMS and MSR technologies on the continuous casting of long products

Continuous casting is a crucial process in the production of long products in the metals industry. It offers several advantages that make it a preferred method over traditional ingot casting: efficiency, productivity, material utilization and energy savings, quality improvement by consistent quality and reduced defects.
The continuous casting process can produce a wide range of cross-sectional shapes and sizes, providing flexibility to meet diverse market demands; alloy versatility allows manufacturers to produce different grades of steel and other metals.
Casting process technological improvements such as Mechanical Soft Reduction (MSR) and Final Electromagnetic Stirring (FEMS) play pivotal roles in enhancing the quality and competitiveness of long products in the metals market, enabling manufacturers to meet its evolving demands while maintaining cost efficiency and sustainability.
Mechanical Soft Reduction (MSR) improves internal quality by reducing centerline segregation and porosity by carefully applying mechanical compression forces along the cast strand, leading to a more homogeneous and compact internal structure, crucial for high performance applications, improving the mechanical and corrosion resistant properties of long products.
Final electromagnetic stirring (FEMS), consisting in stirring the molten metal present in the inner part of the cast strand at proper positions where the solidification is still not completed, improves the internal quality, structural soundness and segregation, by promoting the formation of a finer and more uniform grain structure at the center.
This paper will highlight MSR and FEMS role in modern steelmaking, with the unique challenges and solutions encountered in their application on long product casters. Case studies of recently commissioned casters by SMS Concast will be presented.

Speaker: Marco Abram (SMS group)

Conversion and refining process

2.1.3

376 Online Temperature and Deformation Measurement for Vessel Shell of Oxygen Steelmaking Converters

Information regarding temperature and deformation of the converter shell, particularly the barrel section and top cone, help predict remaining lifetime of top cone, detect damages in refractory, etc. Since the trunnion ring obscures much of the view on the converter, thermal cameras do not provide this information. Hence, sensors have to be arranged directly on the vessel shell. Unfortunately, the high temperature environment disallows the use of electronics, given their maximum working temperature of 80 °C.
In 2019 Danieli Corus developed an online temperature measurement system and the first field tests were done with voestalpine Stahl GmbH in Linz. At first, three temperature measuring elements (Q-Temp 2.0) were installed on converter #9 inside the trunnion ring. After some optimization, these are providing online temperatures of the vessel shell since April 2021.
Based on this design, Q-Temp 2.0 elements have been installed on two 180 tonne converters in Brasil, which are operating since 2021 and 2023. There, 32 elements and two infrared cameras are arranged for temperature image of the complete vessel. In 2024, all three converters at voestalpine Stahl in Linz have been equipped with such elements monitoring the temperature of the top cone close to the tap hole.
In a next step, Danieli Corus upgraded the Q-Temp 2.0 sensor to enable shell deformationmeasurement. This “Q-Temp 2.1” element was developed and tested in the laboratory of Danieli Corus. The first prototype was then installed on converter #7 of voestalpine Stahl in Linz in November 2024. The deformation measurements are very promising and now the long term experience is under the focus. By end of 2024 a revamped 240 t LD-converter in Latin America came into operation, equipped with 12 Q-Temp 2.0 elements, two infrared cameras as well as 4 Q-Temp 2.1 elements.

Speaker: Dr Günther Staudinger (Danieli Corus)

X-2-030_20250725.doc

377 Problem solving with modeling support: evaluation with a numerical fluid dynamic model of the different configurations of the slag-cutting deflector for oxygen jet lance tips in the BOF

In the primary steel production, hot metal produced in the blast furnace (BF) is fed via a ladle to the Basic Oxygen Furnace (BOF), where it is converted to liquid steel. During the metallurgical operations, slag can form and solidify on the refractory walls during tapping. These oxide deposits must be periodically removed, to ensure the regularity of BOF operations over time.
Cleaning operations slow the process, as they require dedicated plant operations. For this reason, a collaboration between RINA-CSM and ADI was set up to find a solution to shorten the BOF ‘cleaning times’, by managing the injected oxygen flow.
The investigated solution (slag-cutting baffle) is based on two countermeasures: an operational one, jet ‘upstream’ flow management, and one 'downstream', thanks to an appropriately designed baffle, adaptable to the heads of the oxygen lances, to properly guide the jet.
To comply with the required effects without impacting on internal lining safety, the oxygen jet blown must meet certain requirements. First, it must be oriented and concentrated within a 'blade' shape, for a ‘compact’ stream. Furthermore, the jet in the BOF must be fast enough to provide for slag melting, but without local velocity 'hot spots’, harmful to internal lining integrity. Therefore, different configurations were designed for the deflecting system (walls, slits), based on the geometric characteristics of the oxygen lances tips.
The study presented hereinafter shows the approach to the problem, the configurations designed, the evaluation criteria of the expected performance, and the results of the computational fluid dynamics (CFD) simulations carried out to verify jet performance. This study made it possible to identify critical issues in the initial configurations, and then to fix them, with solutions considered reliable and industrially applied.

Speaker: Mr Alessandro Dell'Uomo

Digital transformation - Steel materials and their application

6.1.5

378 HyMAS: A Hybrid Multi-Agent Framework for Autonomous Steel Production Planning

Steel is a cornerstone of global infrastructure but its production faces inherent complexity due to high energy consumption, strict quality demands, and sophisticated production process. While traditional planning methods rely on rigid, centralized frameworks, they struggle to adapt to disruptions like equipment failures or material defects, leading to inefficiencies and financial losses. These complexities require autonomous, intelligent solutions that rapidly generate and propose optimized schedules, enabling swift, data-driven rescheduling in response to disruptions. To address this, we present HyMAS, a Hybrid Multi-Agent System, which enables dynamic, resilient decision-making in steel manufacturing. HyMAS employs a hierarchical network of autonomous agents: resource agents govern separate lines, process agents manage entire production stages, and process chain agents coordinate sequential operations. This modular structure allows localized adjustments to production plans without requiring full-scale re-planning, significantly reducing decision time and increasing flexibility. Integrated with Industry 4.0 frameworks, the system interfaces with Manufacturing Execution Systems, leverages digital twins to simulate disruption impacts, and applies machine learning to predict material quality and process mining to monitor performance. In a case study involving a cold rolling mill, three annealing lines, and intermediate storage, HyMAS achieved an 18% efficiency gain and an 8% improvement in on-time delivery. These results demonstrate the system’s ability to improve operational performance while maintaining high levels of adaptability. By leveraging autonomous, intelligent agents, HyMAS rapidly generates and proposes optimized schedules, empowering manufacturers to mitigate financial risks, reduce decision time, and enhance operational agility. Additionally, planning adjustments can now be implemented much more swiftly than before, ensuring a more resilient and responsive production environment. By gradually integrating autonomous, intelligent rescheduling into production planning, HyMAS unlocks the potential of real-time data to systematically enhance efficiency, responsiveness, and operational resilience.

Speaker: Anton Ivanov (PSI Software SE)

379 Artificial Intelligence-based decision support system for optimizing the ladle furnace process in the ALCHIMIA project

The Ladle Furnace (LF) process is fundamental for refining steel before Continuous Casting (CC) and strongly affects some main mechanical features of the final semi-finished steel product. Ferroalloys, deoxidizers and slag formers are added to molten steel, while keeping its temperature within given boundaries through electricity-based heating systems. Several aspects, e.g. the electricity consumption and added materials, can be optimized by formulating adequate control strategies. Through a proper forecasting and optimization system it is also possible to decrease the number of measurements of steel chemical composition between additions.
The paper presents part of the work carried out within the European project entitle “Data and decentralized Artificial intelligence for a competitive and green European metallurgy industry” (ALCHIMIA – G.A. No 101070046), which aims at optimizing the steel recipe in the EAF-based route in terms of energy, scrap mix and added materials. A Decision Support System (DSS) is developed to provide LF operators with optimized control solutions and a better insight in the environmental impact of the production cycle. The DSS includes a digital twin of the LF that leverages the paradigm of Federated Learning for training an accurate neural network-based model. The digital twin exploits real-time data to forecast the final temperature and chemical composition of molten steel before CC, and is at the core of the optimization system that calculates the optimal LF operation. The optimization system is based on evolutionary algorithms to minimize an objective function comprising economic costs and environmental impacts, while satisfying production constraints. The environmental impacts are calculated through a Life Cycle Assessment-based methodology, focusing on the main energy and material flows of each specific heat. The DSS comes equipped with a graphical user interface helping supporting users’ interaction with the developed tools.

Speaker: Stefano Dettori (Scuola Superiore Sant'Anna)

380 Exploring the Potential of Machine Vision (MV) and Artificial Intelligence (AI) in Steel Production

Machine Vision (MV) and Artificial Intelligence (AI) are rapidly evolving technologies poised to transform industries, including steel production. While these technologies are already applied in metallurgical plants—primarily to optimize process models—their potential extends far beyond conventional applications. This presentation aims to challenge traditional thinking and spark discussions of new, creative use cases that enhance production processes, plant logistics, safety, and quality control.

The presentation will begin with a brief overview of key input sensors, such as depth cameras, thermal imaging, and LiDAR, alongside data processing options that leverage edge computing and real-time analytics. Attendees will gain insight into how these components interact to extract meaningful, actionable information.

Building on this foundation, the presentation will showcase novel applications of MV and AI that extend beyond process control. Examples will include enhanced safety monitoring, material logistics, and inspection assistants using AI-driven recognition.

As steel manufacturers seek to increase efficiency, reduce waste, and enhance workplace safety, MV and AI present exciting new opportunities. By understanding how these tools are applied attendees can begin to imagine a myriad of use-cases. This session encourages attendees to think beyond conventional automation and explore innovative solutions that could redefine the future of metallurgical manufacturing.

Speaker: Mr Eric Almquist (StarTool)

381 Transforming Steelmaking: Advanced Automation Solutions Powering the Twin Transition

The steel industry is undergoing a twin transition, where digitalization and sustainability work in tandem to drive efficiency, reduce environmental impact, and enhance productivity. As steelmaking is an energy-intensive process with significant CO₂ emissions, the integration of advanced automation solutions is essential to meet the industry’s growing demands for decarbonization and resource efficiency. By implementing intelligent automation across key steelmaking aggregates, steel producers can achieve realtime process optimization, reduce energy consumption, and ensure consistent product quality.
In the Basic Oxygen Furnace (BOF), automation enables optimized process control with precise endpoint detection. Machine Learning approaches are introduced for further refinement of models, enhancing precalculation accuracy of essential process parameters. Additionally, expert systems automate operator tasks, such as converter tapping.
The Argon Oxygen Decarburization (AOD) process, benefits from new functionalities enabling dynamic adjustment of gas ratios and active temperature control, leading to cost and environmental benefits.
For Electric Arc Furnace (EAF), a new online emissions monitoring module, provides continuous reporting of emissions produced. Integrated valuation algorithms make emissions of the furnace transparent and provide information as a basis for emission reduction. Additionally, AI-driven analytics support better decision-making, reducing variability in the melting process.
In Secondary Metallurgy (SecMet), calculating desulfurization, aluminum fading, and homogenization is challenging due to the dynamic nature of molten steel/slag movement. Traditional models calculate these parts separately, requiring extensive parameter adjustments. New Process optimization functions use a kinetic model to predict circulation movement, resulting in more precise predictions of sulfur and aluminum values.
By integrating digital technologies such as machine learning, AI-driven analytics, and real-time monitoring, steel producers can align industrial performance with sustainability goals, reducing carbon footprints while maintaining high productivity. This comprehensive approach to automation across BOF, AOD, EAF, and SecMet supports the twin transition, ensuring a smarter, cleaner, and more competitive steel industry for the future.

Speaker: Mr Andreas Rohrhofer

382 Technology Consulting Meets Operational Excellence to Improve Steelplants Operations

Steel plants operating for extended periods tend to stabilize into a steady operational state, which may not necessarily align with their peak production potential. Emerging challenges, such as rising energy costs and the task for decarbonization, necessitate a more detailed analysis and enhancement of existing operational processes integrating push and pull scenarios.

With automation, a vast amount of process information and data is already being collected. However, efficiency assessments and optimization efforts often rely solely on average values, overlooking critical variations. A comprehensive evaluation of the entire value stream along the production – supported by distinguishing between normal and unique production situations integrating special cause variations – can provide key insights into areas for operational improvement beyond the evaluation of just averages.

The combination of technological expertise, production know how with operational excellence methodologies can help identify those additional improvement opportunities.
This can be achieved through updated standard operating procedures (SOPs), identifying and controlling input variation, visual planning, and enhanced planning discipline, all of which drive significant improvements without requiring substantial capital expenditures (CAPEX).

However, bridging the gap between methodological frameworks and real-world operations integrating state of the art technological solutions remains a challenge for both consulting and operational teams.

Speaker: Dr Lukas Borrmann (SMS group)

Ironmaking Sintering & Pelletizing

1.2.1

383 Practical Sintering Guidance System: Integrating Data-Driven and Transient Models

The digital transformation of the sintering process requires controlling the return ore ratio, which is the proportion of fine sintered ore particles smaller than 4 mm that cannot be used in the blast furnace, within a target range. When the return ore ratio is too high, the productivity of the sintering process decreases. On the contrary, when we aim for an excessively low return ore ratio, it leads to high production costs.

In the conventional manual operation, since the operators took control actions only after the return ore ratio increased, it remained high for approximately two hours until the effects of the control actions appeared, resulting in low productivity. In addition, the operators tended to increase the quicklime ratio to reduce the return ore ratio unnecessarily, and the production costs increased.

To address the problem and achieve the efficient and productive sintering process, we took a data-driven approach. We identified factors effective for predicting the future return ore ratio from big data (2,000 items) using the stepwise method, and these factors were fed into a machine learning model. This enables the accurate prediction of the two-hour-ahead return ore ratio for taking proactive control actions before the return ore ratio fluctuates.

Moreover, we developed a transient model that can predict the sintering bed temperature. Based on these two models, we constructed an operation guidance system that derives the optimal control actions to reduce production costs without increasing the return ore ratio. It also considers the operational constraints on the sintering bed temperature. The validation results in an actual plant demonstrated that the developed guidance system successfully decreased the quicklime ratio by 12% compared to the conventional manual operation, achieving the digital transformation of the sintering process.

Speaker: Satoki Yasuhara (JFE Steel Corporation)

384 TRANSinter – Sintering process role in the (partial) transition to the Direct Reduction Route

To drastically reduce CO2 emissions, European steelmakers are considering a transition from the Blast Furnace (BF) route to the direct reduction (DR) route. TRANSinter investigates solutions to support the first step in the transition step based on the valorization of existing sinter plants.

Following solutions are being investigated :
- Adapted sinter for use in DR shafts as an alternative to DR grade pellets and a way to valorize by-products onsite after the transition.
- Increased recycling rates to keep valorizing by-products (including from the DR route) in spite of the decreasing number of sinter strands in operation.
- Cleaner sintering processes including
• bio-coals made from low quality residues (such as sewage sludge)
• an original waste gas recirculation layout
• process actions
• end-of-pipe treatments that are yet to be tested at sinter strands.

These solutions are being investigated using a wide range tools ranging from lab trials and modelling work to pilot scale trials, which led to early results including assessment of:

• the maximum amount of standard sinter that can be fed to a DR shaft and possible adaptations to increase it
• the impact of by-products mixes for different future scenarios on sintering process (including environmental performance)
• a wide range of emission reduction solutions including thermo-chemical conversion of low-value residues into solid fuel.

This research is funded by the Research fund For Coal and Steel (RFCS), project # 101112600 , July 2023 to December 2026.

Speaker: Hubert Fouarge (CRM group)

385 Real-Time Iron Ore Quality Optimization in Sintering and Pelletizing Using Integrated Online Analyzer and Advanced Process Control Systems

Sintering and pelletizing are critical upstream process that impact the performance of ironmaking and steelmaking operations through the quality of sinter and pellet feed. Conventionally, iron ore quality has been monitored through offline laboratory analyses. However, it limits the potential of process optimization, as it does not allow for timely adjustments in response to real-time process variations. This study presents a novel approach to real-time ore quality optimization by integrating online analyzers with an advanced process control (APC) system across sintering and pelletizing operations. The pro-posed solution leverages proven analytical technology to deliver continuous elemental and mineralogical measurement of key performance indicators (KPIs), including Fetot%, basicity, moisture, MgO%, SiO2 % and Al2O3%. The real-time composition data of the feed stream is used as input to a model predictive control system, enabling closed-loop process control of material proportioning. By enabling continuous quality monitoring and automated process adjustment, this integrated solution not only optimizes ore quality and material costs in sintering and pelletizing but also enhances productivity, energy efficiency, and decarbonization potential in downstream blast furnace ironmaking and electric arc furnace steelmaking operations.

Speaker: Dr Wenjing Wei (ABB)

386 Comparative mineralogical characteristics of different Iron Ores

The formation and evolution of our planet have been marked by numerous geological events and transformations, significantly influencing the mineralogical characteristics of iron ore deposits. Iron ore, an important raw material of the steel industry, is globally recognized for its critical role in steel production. Understanding its intrinsic properties is essential for optimizing processes, reducing pollutant emissions, and achieving cost savings.
Despite this, the steel industry often relies solely on the chemical and physical attributes of iron ore for its transformation into agglomerates used in reduction reactors, thereby missing opportunities for enhanced process control.
This study delves into the deeper mineralogical characteristics of iron ores, highlighting the microscopic differences found in samples from various regions. By employing advanced techniques such as optical microscopy, X-ray diffraction, and Scanning Electron Microscope, we aim to provide a comprehensive analysis that supports more efficient and sustainable steel production.

Speaker: Erica Rodrigues

387 Cold Agglomerated Iron Ore Pellets Industrial Trial – High quality manufacturing and their performance in the Blast Furnace

Binding Solutions Ltd have developed a cold agglomeration technology that considerably reduces the CO2 emissions associated with agglomeration of iron ores for the blast furnace process. Bespoke tests have proven the metallurgical performance of these cold agglomerated pellets at temperatures well above those used in ISO standards.
Using the company’s own pilot plant in Middlesbrough, UK, 300 tonnes of pellets was produced using a Canadian concentrate and a binder formulation of less than 3%. A comprehensive monitoring and control system was put in place, consisting of hourly checks on the Cold Compressive Strength (ISO4700:2015), twice daily testing of Tumble and Abrasion Index (ISO3721:2015) and RDI-2 (ISO4696-2:2015) methods. Representative samples were tested for high temperature degradation using Interrupted HOSIM tests at 750°C, and complete HOSIM tests of around 3 hours. The HOSIM tests were undertaken internally using a gas composition profile designed to replicate 190 kg/thm coal injection at 8% oxygen enrichment.
Various physical properties of the pellets were also monitored to ensure process consistency. These included but not limited to Pellet weight, Pellet thickness, Moisture content of both the mix and the cured pellets. A system was developed to provide real time feedback to the operators to allow them to see variations in the pellet properties and therefore make process changes to improve the overall performance of the pellet.
The pellets will be charged into Queen Bess blast furnace, British Steel, at 8% for a day. Their impact on process stability will be closely monitored for signs of gas channelling and poor burden descent. The effect on thermal state will be monitored. Additional sampling from the dust catcher during and after the trial will be implemented.
The purpose of the trial is to ensure no adverse impact on process stability, following which a larger scale trial will be planned.

Speaker: Peter Warren (Binding Solutions Ltd)

Process Optimization & Control

6.1.2

Convener: Luca Piedimonte (Ori Martin)

388 Demonstration of XR experience via Hands-On Session

To better demonstrate the entire operation cycle of the SCI framework at the event, given the impracticality of bringing bulky devices, it has been decided to create a digital twin of the process, to be shown to the audience via smart glasses. The interactive digital twin will display the various functional parts of the project, allowing the components created by individual partners to be appreciated.

Speaker: Emanuele Borasio (weAR Srl)

Waste Utilization & Carbon Capture and Utilization

5.2.4

Convener: Andrea Grasselli (Tenova)

389 Green Steel Initiatives Supported by Enhanced Slag Engineering Using High-Alumina Circular Metallurgical Additives

Desulphurisation in the steel ladle requires a reactive slag with high CaO dissolution. Conventional slag fluxing agents applied during this secondary metallurgical refining step include calcium aluminate additives and fluorspar to maximise the dissolved CaO. However, calcium aluminate additives can have a high carbon footprint due to their energy-intensive production process and the use of fluorspar is associated with both environmental concerns and refractory wear. Stahlwerk Thüringen (Germany) is committed to sustainability, with a green steel strategy that includes reducing resource use and implementing stepwise improvements in process efficiency. To support these initiatives, RHI Magnesita and MIRECO conducted an industrial feasibility study to determine if typical fluxes used during steel desulphurisation in the ladle could be replaced by a high-alumina circular metallurgical additive derived from recycled refractory material. This article describes the metallurgical consulting provided by RHI Magnesita during the trial series, as well as the e-tech slag engineering tools that were used for efficiency optimisation calculations and enabled an appropriate balance between desulphurisation rate, additive application, slag volume, and purging gas consumption to be determined. Furthermore, extensive steel and slag sampling was performed, and the chemical and mineralogical results enabled an in-depth evaluation of the metallurgical process during the sequential replacement of calcium aluminate and fluorspar with a cost-effective, low carbon footprint slag fluxing agent.

Speaker: Florian Kek (RHI Magnesita)

390 Physicochemical properties of electric steelmaking slags for the mitigation of CO2 emissions: Active use of HBI with various intrinsic carbon

It is well known that global CO2 emission from steel sector is 7-8%, which is approx. 1/3 of industrial energy use. Hence, many steel companies are trying to develop the electric arc furnace (EAF) and/or electric smelting furnace (ESF) steelmaking processes instead of blast furnace (BF) and basic oxygen furnace (BOF) integrated routes by employing high amounts of direct-reduced iron (DRI) and/or hot briquetted iron (HBI) to mitigate CO2 emissions. The DRI/HBI as substitutes for virgin scrap in EAF has been used because DRI/HBI does not have tramp elements. Unfortunately, however, commercially available DRI contains the relatively high levels of phosphorus and gangue oxides, which adversely affects not only the steel properties but also the operation efficiency. Alternatively, integrated steel mills have focused on the ESF process by keeping conventional BOF to produce high-end quality products. The H2-reduced DRI or HBI are charged in ESF in conjunction with fluxes and carbon sources, producing hot metal. The high-grade iron ores (Fe>68%) are economically used in EAF, whereas low-grade iron ores (Fe<65%) are targeted to be used in ESF. In the present paper, the challenging points regarding the high temperature physical chemistry of slags to achieve the improved and stable EAF or ESF technology on the way to green steel will be reviewed, and the recent experimental and modelling research will be discussed. For example, the initial melting phenomena of HBI and the slag formation behavior was observed using a high-frequency induction furnace. Main component of gangue oxides in HBI was SiO2, Al2O3, and CaO in conjunction with unreduced iron oxide. To increase the dephosphorization efficiency, the distribution ratio of phosphorus between metal and slag was simulated using FactSage thermochemical software and was compared to the measured results.

Speaker: JOO HYUN PARK (Hanyang University)

Predictive Maintenance & Equipment Optimization

6.1.3

Convener: Luca Piedimonte (Ori Martin)

391 Automation on thermal control of blast furnace

To realize efficient and stable operation of a blast furnace, accurate process control through automation is crucial. In this study, we developed an automatic control system for hot metal temperature (HMT). To cope with the slow and complex process dynamics of the blast furnace, we first built a two-dimensional (2D) transient model that can simulate the chemical reactions and the heat transfer phenomena in real time. The estimation accuracy of HMT improved significantly by reproducing a chemical reserve zone where the gas reduction of iron oxides is close to the chemical equilibrium. To use the 2D transient model persistently in the process control, the estimation error caused by unmeasurable disturbances, such as the change of material characteristics, is an issue. We successfully incorporated the effect of disturbances into the model calculation and maintained the estimation accuracy by adopting moving horizon estimation (MHE) algorithm which successively correct the model parameters online. Subsequently, we constructed a control algorithm that calculates the optimal target pulverized coal ratio (PCR) to control HMT using nonlinear model predictive control (NMPC) based on the eight-hour-ahead HMT predictions by the 2D transient model. Finally, we developed a control system that automatically adjusts the target PCR and pulverized coal flow rate. Evaluation in an actual plant showed that the developed control system successfully suppressed the effects of disturbances such as changes in the coke ratio and blast volume, reducing the average control error of HMT by 4.6℃ compared to the conventional manual operation. The developed control system has been applied to multiple blast furnaces at JFE Steel Corporation, contributing to the reduction of the reducing agent ratio (RAR) and CO2 emissions.

Speaker: Ryosuke Masuda (JFE Steel Corporation)

392 DIGITAL TRASFORMATION IN REHEATING AND HEAT TREATMENT FURNACES: SHP

The digital transformation of industrial steel plants is crucial for optimizing efficiency, enhancing product quality, and ensuring sustainability. By integrating digital technologies, these plants can significantly improve monitoring, control, and predictive maintenance of reheating and treatment furnaces. Traditional systems often lack detailed real-time data and rely on external observations, leading to undetected issues and suboptimal performance.
The Shape (SHP) system exemplifies this transformation by creating a comprehensive digital twin of the furnace, including burners and other critical components. It enables real-time and historical data analysis of various physical and chemical quantities, such as pressures, temperatures, optical flame data, and mechanical vibrations. This data helps maintain optimal operating conditions, combustion efficiency, and predictive maintenance, adding significant value to the thermal process.
The SHP system architecture includes smart sensors installed on various furnace parts to analyze critical quantities. These devices perform significant data processing onboard, optimizing data sampling methods and frequencies based on operating regimes. They transmit data via long-range wireless communication to gateways, ensuring reliable communication and simplifying installation. Data is then transmitted through the plant LAN to a micro server, which stores the data locally. This server provides access through an intuitive web interface for real-time and historical data display, performance indicators, and fault alarms. Local data storage eliminates the need for cloud processing, ensuring data ownership protection and low impact on the plant's Ethernet network.
The SHP system enhances information quality and quantity, enables predictive maintenance, and offers optimization suggestions. It supports the creation of virtual sensors and real-time process evaluation, improving plant reliability and product quality. An industrial application example demonstrates the system's capability to monitor critical variables, calculate fuel and air flow rates, and derive combustion efficiency and component health, ultimately optimizing process quality and enhancing plant reliability.

Speaker: Simone Zunino (Danieli & Officine Meccaniche S.p.A.)

393 Advantages of manufacturer expertise and machine self-learning for effective predictive maintenance of industrial gearboxes

Industrial gearboxes play a crucial role in steel industry plants by providing the required speed and torque for the operation of several machines, thus affecting the efficiency and reliability of various processes. Within this scope predictive maintenance is employed to identify potential issues before they lead to costly downtime or catastrophic failures.

In the field of industrial gearboxes predictive maintenance is significantly enhanced by leveraging the manufacturer's in-depth knowledge and integrating machine self-learning capabilities. This approach moves beyond basic monitoring by providing a more effective and accurate assessment of a gearbox's condition.

The manufacturer's expertise, embedded within the condition monitoring system, provides design and calculation data of drive components, such as gears and bearings, as well as the type of oil used, its manufacturer and its storage time. This foundational knowledge enables the system to interpret sensor data more effectively. For example, the system can differentiate between normal operational wear and potential anomalies, leading to more precise predictions about the remaining service life of the components.

Moreover, the integration of self-learning algorithms through the analysis of operating states and cluster analysis improves the predictive capabilities over time. As the system gathers more data, its ability to detect patterns, forecast oil level, and predict both short-term and long-term failures grows. This allows the system to provide automated recommendations for action. The system also identifies and notifies users of anomalies and outliers like overloads. This not only maximizes the utilization of components but also facilitates the planning of maintenance activities, reducing downtime and costs while increasing safety. Consequently, end-users become less dependent on experienced service staff as the system continuously learns and improves its predictive accuracy. Ultimately, the combination of manufacturer expertise and machine self-learning provides an integral and highly effective approach to predictive maintenance.

Speaker: Alberto Scarmi (SEW-EURODRIVE)

394 Harnessing Data Lakes for Global Maintenance Service: Insights and Improvements through Advanced Data Analysis

In the era of big data, organizations are increasingly leveraging data lakes to store vast amounts of unstructured and structured data. This paper explores the transformative potential of data lakes in the context of global maintenance services.
By integrating advanced data analysis techniques, we aim to uncover actionable insights that drive service improvements across various locations and technologies.
Our study examines the methodologies for effective data lake management, the challenges of data integration, and the benefits of real-time analytics in maintenance service operation. Through case studies and empirical data, we demonstrate how digital transformation in maintenance can achieve significant performance enhancements and maintain a competitive edge in the global market.
This research contributes to the growing body of knowledge on data-driven decision-making and offers practical recommendations for leveraging data lakes to optimize service delivery.

Speaker: Michael Weinzinger

Control and modification of the non metallic inclusions

2.1.2

395 Comparison of methods for modification of oxidic non-metallic inclusions using alkali elements on a laboratory scale

The cleanness of modern steels is of utmost importance as non-metallic inclusions can have detrimental effects on the mechanical properties of the finished product, as for example fatigue strength or notched impact toughness. Especially, hard NMI have a lower formability than the surrounding matrix, which can lead to crack initiation in the material during forming. Additionally, NMIs often lead to problems during production, as for example clogging phenomena. Cleanness-sensitive steel grades are typically deoxidized not by additions of aluminum but rather by silicon or manganese deoxidation to avoid the formation of large amounts of hard and non-deformable alumina inclusions. Nonetheless, these particles cannot be avoided completely and still pose serious threats to the quality of the steel, even in low numbers. To counteract this, the second possibility of dealing with unwanted NMI is to change their chemical composition and with that influence the mechanical properties like hardness and deformability. Previous research indicated that alkali elements could possibly achieve modification of oxidic particles, leading to a reduction in hardness. Modification has been verified theoretically by thermodynamic calculations using FactSage. Building on this, different methods of NMI modification using alkali elements were developed and compared in the course of this work. First promising results of alkali-modification using carbonatic sodium and potassium and respective modification rates are presented. Future work will show the impact of this modification on the mechanical properties of the inclusions and the steel.

Speaker: Nikolaus Preisser (CDL-IMAS, Montanuniversität Leoben)

396 Evolution of non-metallic inclusions in non-oriented electrical steel: Industrial observations and laboratory test results

Non-oriented electrical steel is widely applied as core material for several electrical machines, such as generators or electric motors due to its great soft magnetic properties. Besides grain size, precipitates, defects and grain orientation, non-metallic inclusions (NMI) also have a decisive effect on the magnetic properties of non-oriented electrical steel. Inclusions not only inhibit grain growth, cause lattice distortion, but also hinder domain wall motion and thereby deteriorate the magnetic properties of the steel.
This study investigates the change in the inclusion landscape of non-oriented electrical steel over different production steps. Therefore, industry samples from the ladle furnace, Ruhrstahl Heraeus (RH) plant, tundish, mold, slab, hot rolled sheet as well as cold rolled sheet were analyzed using automated SEM/EDS measurements. The detected NMIs of each sample were compared in regard of chemical composition, number per mm2 and mean equivalent circular diameter (ECD). Additionally, laboratory trials in a resistance-heated Tammann-type furnace with raw material from industry (hot rolled sheet) were carried out, examining the influence of rare earth elements (Ce and La) on the inclusion landscape.
Concerning the industry samples, the number of NMIs per mm2 diminishes with ongoing processing until the final product. Furthermore, a slight increase in the mean ECD is observed. The distribution of NMI classes changed from primarily oxides in the ladle furnace sample to comparable amounts of sulfides, nitrides, oxide-sulfides and nitride-sulfides in the final product. The laboratory samples alloyed with Ce and La respectively showed a reduction in NMIs per mm2 compared to the input material. Moreover, the mean ECD increased in both cases, although the increase was more pronounced with La. The reduction in number per mm2 and the increase in ECD suggest an improvement of the magnetic properties.

Speaker: Bernhard Sammer (Christian Doppler Labortatory for Inclusion Metallurgy in Advanced Steelmaking)

397 Evolution Behavior of Non-Metallic Inclusions in Al-killed Ti-bearing Ferritic Stainless Steel

High-Cr and Ti-bearing ferritic stainless steel (Ti-FSS) has superior corrosion resistance compared to other steel grades. The Ti-FSS requires not only high corrosion resistance and formability but also superior cleanliness of the cold rolled sheet. Specifically, the cleanliness of Ti-FSS has been improved through the vacuum oxygen decarburization (VOD) and the ladle treatment (LT) processes. Nevertheless, there are still unresolved problems such as large fluctuations in Ti-yield and the formation-removal behavior of non-metallic inclusion (NMI) due to various factors including Al deoxidation practice and slag-metal reactions after Ti alloying. Moreover, TiN and Mg(Al,Ti)2O4 spinel-type inclusions formed in molten steel after Ti alloying causes nozzle clogging and surface defects in the final products. Therefore, it is essential to design the refining slag with excellent inclusion removal rate as well as to optimize the deoxidation practice in VOD process. In the present study, the Ti-yield in the Ti-FSS melt as well as the evolution behavior and number density of NMI in molten steel was investigated by varying input conditions of aluminum and titanium as well as the contents of TiO2 and CaF2 in the slag during the reaction between Ti-FSS melt and VOD slag. As the TiO2 content in the slag increased, the Ti-yield in the molten steel increased and the average Ti2O3 content in the NMI increased after titanium addition. When the Al/Ti input ratio increased, the Ti-yield in the molten steel increased. Also, Mg pick-up from the slag also increased with increasing Al/Ti ratio, resulting in an increase of MgO content in NMI and thus spinel-type inclusions were modified into MgO inclusions. When the CaF2 content in the slag increased, the total dissolution time of NMI decreased due to the decrease in slag viscosity, resulting in a decrease of the number density of NMI in the Ti-FSS.

Speaker: Mr DONGYUL JUNG (Hanyang University)

Process Transformation & Strategy

5.2.5

Convener: Andrea Grasselli (Tenova)

398 Development of Oxygen-fuel Burner Design for Electric Arc Furnaces under Supersonic Flow Conditions

To achieve a carbon-neutral EAF system for high-quality sheet production, rapid scrap melting is essential for efficient DRI/HBI dissolution.
This study presents an integrated oxygen lance-burner design to enhance thermal efficiency and melting kinetics.
Experimental validation and numerical simulations were conducted to assess performance and optimize key parameters, with findings and strategies discussed.

Speaker: KYUNTAE KIM (Hyundai-steel)

399 Secondary metallurgy challenges in the transformation from oxygen to electric steelmaking

The path to reducing steel's CO₂ footprint is increasingly clear, with the industry shifting toward electric arc furnace (EAF) steelmaking. This transition relies on recycled scrap and partially substitutes virgin materials with direct reduced iron (DRI) or hot briquetted iron (HBI). However, the changing quality of input materials, particularly the reduced purity of raw materials and variability in scrap, poses challenges for secondary metallurgy processes, including ladle refining furnaces, vacuum tank degassers, and RH recirculation degassers. Controlling and reducing sulfur, nitrogen, and tramp elements has become more complex under these conditions.

To address these issues, adjustments in steel refining practices are essential. This paper discusses revised processing routes, the installation of additional equipment, and the redesign of meltshop layouts to optimize operations with diverse and lower-quality feedstock. These measures are critical for maintaining product quality while aligning with the industry's push toward more sustainable practices.

By adapting processes and infrastructure, the steel industry can effectively manage the challenges associated with varying material inputs and achieve significant CO₂ emissions reductions. The paper provides insights into these adjustments, offering a framework for navigating the complexities of transitioning to environmentally sustainable EAF steel production.

Speaker: Mr Andrea Pezza (Badische Stahl-Engineering)

400 Towards Green Steel: Challenges, Opportunities, and Strategies for Decarbonization

The steel industry, responsible for 7% of global CO₂ emissions, significantly contributes to environmental pollution and intensive water consumption. Decarbonizing the sector requires adopting innovative technologies such as hydrogen-based direct reduction, recycling in electric arc furnaces (EAF), and iron ore electrolysis. However, this transition presents major challenges, including the high cost of new technologies, the need for an efficient renewable energy and smart grid infrastructure, scalability issues of emerging solutions, and dependence on raw material purity, which affects both efficiency and production costs.
At the same time, standardization and regulation of the industry are crucial to prevent greenwashing risks and ensure market transparency. Instruments such as the EU’s Carbon Border Adjustment Mechanism (CBAM) and carbon pricing policies can incentivize sustainable practices, while international collaboration and targeted investments will accelerate the shift.
The objective of this paper is to provide a critical analysis of the steel industry's transition toward low-emission processes, highlighting key technological, economic, and regulatory challenges. Through a comparative approach, the barriers to adopting new technologies and possible strategies to overcome them will be examined, focusing on practical solutions that balance sustainability and competitiveness.
The path to truly green steel is long and requires strong commitment from both businesses and governments. If implemented correctly, these steps could not only decarbonize the steel industry but also position steel as a fundamental pillar of the global green transition. A crucial aspect of this journey will be the continuous monitoring and improvement of adopted solutions to ensure sustainability goals are effectively met and maintained over time.

Speaker: Prof. Silvia Barella (politecnico di milano)

Digital transformation - Steelmaking Continuos Casting

6.1.6

Convener: Michele De Santis (Rina Consulting - Centro Sviluppo Materiali SpA)

401 Crafted Scrap: Scrap Yard Automation and Advanced Sensors

Steel circularity represents a sustainable strategy aimed at maximizing reuse of steel material, significantly contributing to the decarbonization of steel production. This approach encompasses the sustainable design of steel end products, resource-efficient steelmaking, and the recycling of steel products. Resource-efficient steelmaking is achieved through electric arc furnaces or converters prioritizing the use of recycled charging materials like steel scrap while minimizing the use of virgin materials such as pig iron or hot briquetted iron. Optimizing energy use and carbon footprint in these processes necessitates a thorough understanding of the composition of scrap portions charged into the melting unit to adjust process parameters accordingly. The recycling process involves collecting and pre-processing scrap through cutting, shredding, or cleaning. Efficient sorting, supported by chemical and/or optical analysis, is crucial for providing scrap of defined composition , which is essential for producing high quality steel grades with strict requirements. A scrap composition with defined quality and well-known properties is termed crafted scrap.
This paper presents a system of advanced sensor-based applications designed to determine the quantity and quality of scrap and track individual scrap portions throughout their lifecycle at a steel plant. It details how scrap quality is assessed using artificial intelligence-based camera image analysis for scrap type classification and detection of undesired objects, with the result applied to scrap pre-processing and sorting as well as inspection of incoming deliveries. Additionally, it demonstrates how scrap quantity is estimated by creating volumetric maps of scrap yards and containers using LIDAR sensor data. A comprehensive scrap tracking approach is also outlined, covering delivery by train or truck, material handling, scrap processing, manipulation into scrap baskets or chutes, and finally charging into melting units, facilitating real-time inventory management. Practical implementations at an electric steelmaking plant confirm the effectiveness of these approaches.

Speaker: Andreas Rohrhofer

12:20 lunch

Additive Manufacturing

4.2.1

Convener: Davide Maghini

402 Thermophysical property measurement of selected Nickel based superalloys by voestalpine BÖHLER Edelstahl GmbH & Co KG using a gas-tight Furnace Rheometer System and an Electromagnetic Levitation Apparatus

Thermophysical property data of liquid alloys, like viscosity and surface tension, are key input parameters in numerical fluid simulations. For production processes with extreme conditions and under harsh environments, like in steel industry, these simulations are a promising option to gain a deeper insight into those processes that are difficult (or even impossible) to study by measurement techniques otherwise. Therefore, thermophysical property measurements are performed in research and development at voestalpine BÖHLER Edelstahl to enable such simulations and consequently allow to optimize the processes itself (e.g. the gas atomization for AM powders) or to improve the properties of the products from these processes. A commercial high-temperature furnace rheometer system (FRS) by Anton Paar is used to measure viscosity while surface tension and density are obtained using a terrestrial electromagnetic levitation (EML) setup.

For this talk, a selection of common Nickel based superalloys by voestalpine BÖHLER Edelstahl is studied using the FRS and EML and results for the different alloys are compared to each other. As required for aerospace applications, these alloys follow clear and detailed specifications and the obtained data is therefore not only valuable for model validation in basic research but also for future material comparisons. The availability of the data is also beneficial for simulations where BÖHLER alloys are used in a subsequent manufacturing process, e.g. selective laser melting of AM powders (BÖHLER AMPO).

Recent FRS measurement results on Nickel based superalloys showed unexpectedly large viscosity values that are presumably caused by strong oxidation of the sample material. It was therefore decided to upgrade the FRS with the so-called “gas-tight” option that promises oxygen-free measurements of the melt. Hence, it is planned to put an emphasis on the comparison of the measurement results obtained before and after the upgrade.

Speaker: Dr Thomas Leitner (voestalpine BÖHLER Edelstahl GmbH & Co KG)

403 Development and Additive Manufacturing of MoNiCr Nickel Alloy for Energy Industry Applications

One of the investigated concepts for Generation IV nuclear reactors is a molten salt-cooled reactor system. A critical aspect of this concept is the material selected for components of the primary and secondary circuits of the power source, which is exposed to extreme chemical and thermal loading. The loading arises both from aggressive chemical interactions with molten salts at elevated temperatures and from creep stress. Due to the unavailability of specialized materials suitable for this environment, such as the Russian alloy HN80M, the French alloys EM-721 and EM-722, or the Chinese alloy GH3535, a proprietary nickel alloy named MoNiCr has been developed in the Czech Republic.
This work addresses the manufacturing issues related to the MoNiCr alloy, covering conventional casting processes, hot and cold forming into wire form, powder atomization, additive manufacturing (AM), and final heat treatment, including metallographic analyses and mechanical property testing. Final experimental samples were fabricated using Directed-Energy-Deposition (DED) additive manufacturing technology. This modern manufacturing technology was selected due to its capability to produce complex component geometries required in the energy industry, which are often impossible to manufacture using conventional methods.
MoNiCr is a very difficult to form material and is highly susceptible to solidification cracking during additive manufacturing processes. Therefore, considerable attention must be given to the quality of input material for additive manufacturing, whether in powder or wire form. Equally important is the careful selection of process parameters, which has also been extensively addressed in this work.

Speaker: Dr Daniela Nachazelova (COMTES FHT a.s.)

404 Applicability of a Ni-9%P+(a:C-H)DLC multilayer coating to improve the tribological behaviour of AISI 316L screws with internal channels produced by Powder Bed Fusion-Laser Beam

The reduced production times and costs and lower environmental impact of the Powder Bed Fusion-Laser Beam (PBF-LB) technology compared to conventional technologies for producing complex-shaped parts are generating keen interest in the industrial sector. Thanks to its peculiar microstructure, the PBF-LB AISI 316L stainless steel has higher pitting corrosion resistance and mechanical strength than conventional AISI 316L stainless steel; however, it is also characterized by low wear resistance and high friction coefficient, especially in severe environmental conditions.

From this perspective, the Ni-9%P+(a:C-H)DLC multilayer coating represents a promising solution: the deposition conditions have no negative effects on the metastable microstructure of the PBF-LB AISI 316L alloy, and the Ni-9%P interlayer is able to uniformly cover the complex surface and surface defects of the substrate, ensuring good adhesion, continuity and load support to the (a:C-H)DLC topcoat, characterized by high wear resistance and low friction. Furthermore, barreling the substrate would ensure uniform functional properties through a controlled surface finish over the entire surface.

The effectiveness of the entire post-process cycle is evaluated through a complete microstructural and micromechanical characterization on functionalized PBF-LB AISI 316L screws. Optical profilometry and cross-section observations using FEG-SEM/EDS and ion milling were used to analyze the surface roughness and the quality of the multilayer coating, substrate and interfaces. The adhesion of the Ni-9%P layer on the substrate was evaluated by Rockwell indentation (“Mercedes test”) and the practical adhesion of the (a:C-H)DLC on the Ni-9%P interlayer was tested by progressive load scratch testing. Instrumented indentation was used to measure the hardness of both layers (Ni-9%P and (a:C-H)DLC) on the micro/nanoscale.

The results allowed to define the guidelines for the design and production of high-performance coated PBF-LB AISI 316L screws, in order to create innovative components with sustainable materials and processes, capable of supporting the ecological transition in the automotive sector.

Speaker: Dr Gianluca Di Egidio (Università di Bologna)

405 Advanced Materials and Additive Manufacturing for Demanding Industrial Applications: Nickel-Based Alloys for High-Performance Forging Tools

With the increasing demands of industry for materials capable of withstanding extreme conditions such as high temperatures, mechanical stress, and aggressive environments, nickel-based alloys are being increasingly employed. These materials play a key role in the production and maintenance of forging tools, offering an optimal combination of strength, durability, and stability due to their unique properties.
The aim of this research is to analyse the potential use of nickel-based alloys, particularly Nimonic 80A and Inconel 718, for functional layers in forging tools. Although nickel alloys exhibit excellent thermomechanical properties, their high cost makes the production of an entire tool using additive manufacturing financially demanding, limiting their widespread application in industrial practice.
Traditional manufacturing methods often face limitations due to complex geometries, material characteristics, and production speed. Additive manufacturing, particularly using powder and wire feedstocks, opens new possibilities to overcome these barriers and enables the production of intricate structures. A highly effective approach involves the selective application of these materials through additive manufacturing, specifically the Directed Energy Deposition (DED-LB) method, which allows the creation of functional surfaces with optimized properties.
The research focuses on the comprehensive characterization of these alloys in terms of microstructure, mechanical and physical properties, and the impact of additive manufacturing techniques on the final properties of forging tools. The results demonstrate that utilizing these alloys as functional surface layers enhances wear resistance and thermal durability, thereby increasing the service life of forging tools. This research opens new opportunities in materials engineering and highlights the benefits of combining advanced alloys with additive manufacturing in industrial practice. By improving the production and repair of forging tools, this study contributes to greater sustainability and competitiveness in the industrial sector.

Speaker: Dr Martina Koukolíková (COMTES FHT a.s.)

Advanced Materials & Special Applications

3.1.5

Convener: Andreas Kern (thyssenkrupp Steel Europe)

406 Upgrade a heavy section mill to produce high-strength beams with Danieli Thermo-Mechanical Control Process (TMCP)

A heavy beams producer selected Danieli technology and construction capability for the turnkey Thermo-Mechanical Control Process (TMCP) project at its rolling mill.
Thanks to this process, the product portfolio will be expanded with high-strength beams according to Grade 80 ASTM A913/A913M and S500ML EN 10025-4 standards.
High-strength beams offer substantial savings in construction in terms of material weight and fabrication costs (mainly welding) for a wide range of applications, such as high-rise buildings, long-span bridges, constructions in seismic areas, and offshore structures.
These beams are obtained through TMCP from low-alloy grades chemistry steels that provide excellent weldability (no pre-heating required) while achieving good toughness at low temperatures.
The thermo-mechanical control process will be performed by Selective Flange Cooling (SFC) in combination with Quenching & Self-Tempering (QST), treating the entire beam.
The SFC equipment will be installed at the entry and exit sides of the reversing finishing mill through cooling side guides, followed by the QST system at the exit side.
Tests carried out at the Danieli Research Center demonstrated that the new Danieli QST package will grant water savings of up to 30% compared to the previous version.
Carrying out the works during the plant shutdown, which lasts only 30 days, is an engineering challenge that requires plant and civil surveys with 3D scanning, integrated design of the plant and civil works for both existing and new parts, prefabrication of civil and plant components, as well as detailed planning for the site activities to be carried out before and during the shutdown.

Speaker: Mr Luca Gori (Danieli & C. Officine Meccaniche S.p.A.)

407 Advanced Long Rolling Solutions for Efficient Stainless-Steel Production

Walsin Lihwa Corporation has partnered with Primetals Technologies to expand their production of long products and take advantage of the latest cutting-edge technology to meet the growing demand for high-quality stainless-steel products for the Chinese market. This mill was a strategic investment for Walsin Lihwa Corporation’s focus on increasing capacity, reducing delivery times while maximizing in-line processing to produce precision tolerance, and superior surface quality products with greater efficiency to reduce production costs.
To realize these goals, Primetals Technologies incorporated our latest long rolling technological innovations to streamline the process and maximize flexibility, including our latest patented top/down pouring reels with direct water quenching, Throughput Quality Control (TPQC), smart sensors for automatic tension control of the Reducing / Sizing Mill, and Laying Head speed control, to name but a few of the features.
The new combination bar, bar-in-coil and wire rod mill is designed to produce 420,000 tons per year of stainless valve steels, nickel-based alloy steel and numerous stainless grades, including austenitic, ferritic, dual phase and hardening steels. The mill has the capability to roll straight bar products from 18 – 130 mm, bar in coil products from 18 – 40 mm and wire rod in products from 5.0 – 18.0 mm.

Speaker: Mr Stephen (Mark) Shore

408 High End Steel Grade Production with Advanced Cooling Technologies - possibilities for AHSS

Power Cooling offers significant advantages in hot strip mills, particularly for producing modern steel grades with superior mechanical properties. This innovative cooling system features scalable water impact pressure and flow rates, ensuring high cooling rates coupled with precise temperature control far beyond the usual coiling temperature ranges for conventional steel grades. This is especially true for low coiling temperatures where the Leidenfrost effect becomes important. Additionally, it offers a quasi-laminar mode that provides all the advantages of classical cooling sections.
This unique flexibility, combined with highly accurate temperature control, forms the basis for the reliable production of sophisticated steel grades requiring multi-stage cooling, such as bainitic, complex phase, or martensitic grades where self-tempering is necessary, and the length of the cooling section is critical. The precise temperature control available in both the longitudinal and transverse directions of the strip within the bainite start temperature region makes the production of Quenched and Partitioned (Q&P) steels as hot-rolled achievable. This simplifies the production route for the most promising candidates for the third generation of High-Strength Steels (AHSS), characterized by an ECO-index (tensile strength x elongation) above 20000MPa%, significantly reducing downstream processing and production costs.
For conventional steel grades, the high cooling rates achievable offer significant alloy savings via grain refinement, the Hall-Petch effect, and improvements in formability, mechanical properties, and welding properties. For multi-stage cooling, the high cooling rates yield high ferrite nucleation rates, fine cementite precipitates, and short lengths until the holding/quenching temperature is reached, allowing for increased holding times compared to (quasi-)laminar cooling.
Thus, Power Cooling technology not only meets current market requirements for high-strength materials but also positions steel producers to capitalize on future metallurgical demands. This advanced technology is crucial for producing high-quality steel that adheres to the stringent standards of today's industries.

Speaker: Mr Bernhard Viernstein (Primetals Technologies Austria GmbH)

409 Cutting-Edge Technologies To Produce Electrical Steel

Electrical steel (also called Silicon steel), a steel alloy with specific magnetic properties, with low core loss and high magnetic permeability, is extremely sensitive to produce, especially when high performance and low energy losses are critical. The booming electric vehicles market is driving the development of Non-Grain Oriented Silicon Steels with high flux density and minimal core losses for the use in high frequency electric motors, as well as high energy efficient Grain-Oriented Electrical Steels due to the need of charging infrastructures.

To produce of NGO and GO electrical steel, various challenges are being faced. Over the years, process equipment have been improved with advanced technologies to meet those unique challenges. This paper describes these technologies which have been recently widely implemented on new processing lines and cold rolling mills.

Speaker: Mr Alexis Duchene (Fives DMS)

410 Superior product change control at cold rolling mills for enhanced productivity

The paper describes how an expert system automatically calculates the optimal strategy for all product changes based on PDA data, i.e. determining the best combined method of operation from technology clusters such as strip flatness and strip thickness, etc. The next step is to implement digital AI systems that provide forecasts for the optimal product change strategy. Once artificial intelligence provides a sufficient hit rate in its predictions, it generates commands for level 1 and level 2 systems to enable real-time reactions by all mechanical actuators. This system adds value by improving off-gauge length for strip flatness and thickness, as well as enhancing product change stability.

Speaker: Jörn Sieghart (SMS group)

411 Heavy plate applications ensure energy transition – Modern plant concepts for forward looking plate production

Wind power applications are the major enabler for the energy transition. The production of towers and foundations for offshore wind turbines requires the use of heavy plates, characterized by unique metallurgical properties and specific dimensions. Given the strict safety standards and the demand for high performance under extreme conditions, these heavy plates require high toughness and high resistance to crack growth. Manufacturing such plates involves advanced plant concepts, leveraging extensive product expertise, cutting-edge technology, and accurate process control. Heavy-plate mills and slab casters from SMS group are capable of producing the thickest dimensions with the required properties. This paper will discuss the market development and the market requirements and will introduce SMS group's innovative solutions designed to enhance the efficiency of manufacturing these demanding products.

Speaker: Georg Padberg (SMS group)

Digital Transformation & Industry 4.0

6.1.4

Convener: Alessandra Saleri (Forge Fedriga srl)

412 Development of Digital Tools at HYBRIT's Pilot Plant for H2 Direct Reduction

The HYBRIT initiative was launched in 2016 by SSAB, LKAB and Vattenfall with the aim of creating a completely fossil-free value chain from mine to steel, using fossil-free electricity and hydrogen. The focus of technical development has been to build up expertise and to set the technical prerequisites for implementing HYBRIT’s fossil-free value chain in full-scale production. Large parts of the development work have been carried out in facilities that correspond to full-scale industrial production environments in terms of both equipment and process control, but with lower production capacity.
HYBRIT’s pilot plant for direct reduction (DR pilot) has capacity of approximately 1 tonne DRI/hour and has produced more than 5000 tonnes of fossil-free sponge iron since 2021. Data collected from pilot trials include process data, for instance detailing conditions for input and output streams, as well as measurements and material sampling from inside the DR pilot shaft (labelled reactor excavations). This data has provided a unique and solid foundation for developing accurate physics-based models of the H2 direct reduction process. Simulations have in turn supported process understanding and process development.
To leverage the investments in digital tools and extend their utility, efforts have been made to overcome the typically long execution times of detailed models of strongly coupled processes. Fast and accurate models have been developed by training deep neural network (DNN) models on data sets from high-fidelity physics-based models. In addition, the tools´ graphical user interfaces have been tailored based on needs and feedback from engineers and technical staff working at the DR pilot plant. So far, digital applications have been developed for on-line process monitoring and for evaluating process responses in “what-if” scenarios. The applications have been tested during pilot trials running continuously for 6-8 weeks.

Speaker: Henrik von Schenck (Hybrit Development AB)

413 PCIXpert: boosting efficiency and resources utilization

The paper presents the development and implementation of the Pulverized Coal Injection Monitoring Service (Paul Wurth PCIXpert), an innovative solution designed to enhance the operational efficiency and reliability of Pulverized Coal Injection (PCI) plants. Developed by SMS group, PCIXpert addresses the challenges faced by maintenance and process management personnel in monitoring complex PCI installations. The service provides a continuous evaluation of PCI transport performance through the use of key performance indicators (KPIs) and a smart alarm analysis tool.

Paul Wurth PCIXpert introduces a novel approach to the industry by offering a comprehensive, long-term analysis of the entire coal injection transport system, from storage bins to injection lances. This system is distinguished by its use of industrial dashboards and KPIs, enabling users to easily assess plant performance and identify deviations from optimal operation. The process-impact oriented alarm management system categorizes alarms by process and impact severity, facilitating targeted interventions.

The deployment of PCIXpert is currently underway, with full implementation at two PCI locations and partial implementation at another location, where further deployment is in progress. Initial results indicate significant improvements in plant availability and utility consumption. These improvements are attributed to the system's capability to highlight sub-optimal conditions within the plant process, thereby guiding process, maintenance, and operation personnel on where to focus their efforts and what specific issues to rectify.

The expected future benefits of the Paul Wurth PCIXpert include sustained operational efficiency, reduced costs, and enhanced decision-making capabilities for plant operators. By providing an easily accessible web-based service, it ensures that critical performance data is readily available to stakeholders, supporting continuous process optimization and contributing to the long-term success of PCI operations.

Speaker: Ms Yasmine Iciriddir (SMS group)

414 Digitalization of Material Properties Across the Entire Process Chain

Steel-intensive-industrial sectors face ongoing challenges in balancing agility, demographic change and technological renewal. A key solution lies in the evolution of digitalization, moving beyond traditio-nal ERP (order processing), PLM (product development), and MES/BDE (production control) systems. The next stage of digital transformation integrates materials technology and manufacturing processes into enterprise IT infrastructures, enabling a more comprehensive approach to knowledge manage-ment and the possibility to remain as independent as possible regarding additional software. Beyond data collection and processing, the presented best practice contains of an expanded framework fos-tering knowledge creation through a model library that supports fact-based decision-making. A crucial aspect is understanding and modeling the evolution of steel properties along the entire process chain. We present an advanced digitalization environment that enhances the integration of steel materials and processes to accelerate product and process development.

Speaker: Dr Uwe Diekmann (Matplus GmbH)

415 Towards a Standardized Digital Product Pass for Green Steel: Developing Novel Framework with Real-Time CO₂ Tracking and Secure Data Connectivity for ESPR Compliance

Transformation towards climate-neutral production in the metal industry requires innovative solutions for tracking and optimizing greenhouse gas emissions. While major steel manufacturers are already exploring digital product passports (DPP) as part of their sustainability strategies, small and medium-sized enterprises (SMEs) in the metal processing industry often lack standardized and real-time compatible methods for quantifying product-specific emissions.

This paper introduces a novel DPP architecture tailored for SMEs in metal processing, integrating edge-computing-based models to dynamically assess the CO₂ footprint of individual products during manufacturing. Unlike conventional static product information systems, the proposed approach enables real-time tracking of energy consumption at critical process stages, merging sensor data with model-based digital twins. This ensures a more precise, verifiable, and scalable solution for sustainability reporting across the supply chain, with necessary interfaces and access control mechanisms to address privacy concerns of SMEs during product-related data exchange. The architecture leverages industry-compatible interfaces for automated data exchange with existing ERP/MES systems and regulatory platforms, ensuring compliance with the Ecodesign for Sustainable Products Regulation (ESPR) and interoperability with EU-wide standarized data models. By developing a green steel DPP framework that meets future standardization, regulatory and certification requirements, it provides an early-stage solution that aligns with upcoming industry and legislative needs.

Pilot projects in a real-world hot rolling mill and foundry validate the system’s ability to enhance transparency and energy efficiency with real-time emission monitoring. By integrating dynamic energy monitoring into the green steel DPP framework, this research presents a pathway toward standardized and verifiable CO₂ assessment in metal processing. The findings contribute to ongoing EU standardization efforts and set a foundation for scalable, industry-wide applications.

Speaker: Doruk Sahinel (Spherity GmbH)

416 DIGITAL MANUFACTURING FOR THE DEVELOPMENT OF NEW ROLLING MILL FOR BEAMS

The Smart Beam manufacturing (SBM) is the new rolling mill that will allow to verticalize the production in Duferco Group plant of San Zeno Naviglio: a new integrated rolling mill, downstream of the San Zeno steel mill, to allow for optimal verticalization of the steel production, with the goal of becoming the best cost producer of steel beams in Europe.
To reach optimal efficiency of integrated steel and rolling mill, digitalization of plant has been done for continuous casting machine, heating furnace and rolling mill line.
Continuous casting machine, designed for beam blank’s production, has been virtualized using FEM casting simulation software ProCAST: objective of this analysis is to grant process robustness through definition of best design for equipment and process parameters to avoid crack on casted product and increasing productivity of the line.
Heating furnace and rolling line have been virtualized using FEM software DEFORM: using casted product obtained in previous continuous casting simulation with ProCAST, DEFORM digitalizes heating cycle and following roll passes. Objective of these analysis are definition of optimal heating cycle of raw beam blanks to reduce gas consumption, definition of optimal roll pass design for correct shape obtainment, avoiding cracks on product and overloads on rolls, and predictive maintenance for rolling line.
Casting, heating and rolling simulations are fully integrated in ProCAST-DEFORM platform, allowing to perform off-line all trials to reproduce digital twin of Smart Beam Manufacturing rolling mill.

Speaker: Cristian Viscardi (ECOTRE Valente srl)

Digital transformation - Steelmaking Continuos Casting

6.1.6

Convener: Cosmo Di Cecca (Feralpi Siderurgica)

417 Metallurgical Quality Assessment Of Continuous Casting Combining AI, Sensor Information and Machine Vision

Continuous casting has long relied on inspection methods that often detect defects too late, leading to wasted energy, time, and costs. Late detection also limits the ability to intervene in defect formation. Sapotech aims to improve continuous casting control by developing a real-time defect detection system that integrates AI-driven predictions, machine vision, and process sensor data. This approach enhances automation, optimizes process flow, reduces unnecessary processing, and improves safety.

This study explores AI-driven enhancements to reduce latency in defect detection by integrating additional computational blocks into the existing UNet3+ deep learning architecture. The process involves capturing surface images, processing them through an initial stage of the UNet3+ network, passing them through optimized computer vision modules, and then completing analysis within the full architecture to identify defect locations and types in real time.

Additionally, we are investigating the integration of process sensor data—such as mold friction, oscillation frequency, casting speed, and mold temperature—with machine vision for early defect detection. Synchronizing this data with visual information enables a more comprehensive understanding of defect formation mechanisms and lays the foundation for fully automating the continuous casting process.

The effectiveness of our approach is evaluated based on processing speed, hardware requirements, detection accuracy, and true positive versus false positive rates. Future work will focus on fully integrating sensor data for early defect detection, further advancing the automation of metallurgical casting.

Speaker: Ms Elena-Briana Boeru (Sapotech Oy)

418 Estimating Reheating Time for Steelmaking Ladles Using Optimization-Based Machine Learning Approach Integrated with a Physical Thermal Model

Controlling molten steel temperature is pivotal in steelmaking as it influences energy efficiency, process performance, and product quality. Among the factors affecting molten steel temperature, steel ladles, massive refractory-lined vessels used to transport and refine molten steel from the tapping station to the continuous caster, play a crucial role. Ensuring the molten steel reaches the continuous caster at the proper temperature requires control of the tapping temperature, which is affected by the ladle's thermal state. When a ladle cools due to a prolonged waiting period before tapping, it can decrease the steel's temperature more than desired. Reheating the ladle helps prevent this temperature drop and reduces the need for a higher initial steel temperature. It also protects the refractory lining from thermal shock. However, determining the optimal heating time is complex as it depends on multiple factors influencing steel temperature and a range of process parameters. This study proposes an optimization-based machine learning approach to estimate the required heating time to achieve the target temperature for continuous casting. The algorithm operates within an environment integrated with a physical thermal model that simulates the steel temperature throughout the process. An agent adjusts heating times based on process variables, such as ladle empty time before tapping and initial refractory temperature to minimize the deviation from the target temperature. Through repeated adjustments, the agent learns to determine the minimum reheating time to ensure the molten steel arrives at the caster in an acceptable temperature range. By accurately estimating the minimum heating time, this hybrid framework adapts to different steelmaking scenarios, reducing excess energy use and minimizing the need for unnecessarily high tapping temperatures. This approach can enhance thermal management efficiency, dropping production costs and improving steel quality. It also helps reduce CO2 emissions, contributing to a more sustainable industry.

Speaker: Fatemeh Azizi

419 Fully automated antimixup solution with LIBS technology, ensuring 100% check of the bar and billet proven over years of process operation.

A reliable material identification along the entire rolling process chain is a high priority in today’s rising demand on fault-free shipment. For special alloy producer, a mixup in delivered product could result in complete cancellation of the shipment, penalty charges as well as loss in reputation. In this regard, currently used positive material identification (PMI) technologies such as spark, XRF or magnetic induction testing face challenges such as small diameter bar, need for surface preparation and physical contact, yearly radiation safety certificate or reference bar. Therefore, there is a growing need for PMI solution that is inline applicable, incorporates fully automated sample preparation (e.g. remove human operator), controlled by level 2 system, precise (e.g. comparison based on heat chemistry) and universal (e.g. bright bar, black bar, billet).

LIBS (laser-induced breakdown spectroscopy) based sensor opens a new opportunity toward digital rolling mill, providing real-time material composition analysis without interrupting production. Depending on the risk of mix-up, this PMI sensor can be integrated into the existing process (e.g. finishing line, NDT line, before reheating furnace), fully compatible with the MES systems and enables fast intervention to correct mix-ups or other material-related issues. This oral presentation will discuss long-term process operation data from different LIBS-based PMI sensors currently operational in multiple producer’s facilities.

Speaker: amit ahsan (SECOPTA analytics GmbH)

420 Explainable AI for Property Prediction in Scrap-Based Steel Production: A Public Data Implementation

The global shift towards greener practices has created significant challenges for the material manufacturing sector. One key example is the need to increase the use of scrap metals in production to reduce the strain on natural resources and promote a circular economy. However, using scrap metals inevitably introduces impurities, which can greatly affect the properties of the final material. This risk has resulted in resistance within the industry to adopt scrap metals widely.

To promote circularity in material manufacturing, it is crucial to improve the industry's understanding, confidence, and ability to work with scrap metals. One way to achieve this is by developing an AI tool that can assist in material production, helping users make informed decisions to mitigate the impact of impurities. This tool would rely on a deep understanding of the relationships between material properties, microstructure, processing methods, and composition. As with any AI system, the quality and quantity of training data are critical. Therefore, multiple datasets are used to investigate those relationships after careful data pre-processing.
Building upon my previous work, which successfully utilized industrial data to predict material properties through machine learning and explainable AI techniques, this research transitions to publicly accessible datasets. I demonstrate a comprehensive data pipeline for predicting mechanical properties of steel using chemical composition and process parameters. While my analysis focuses on public datasets, the methodology is readily transferable to industrial environments when appropriately adapted. Furthermore, I examine the integration of microstructural data to deepen our understanding of the underlying processes.

Speaker: Gerfried Millner (School of Material Science and Engineering, Nanyang Technological University)

421 THE PIVOT ROLE OF MODELLING IN PROBLEM-SOLVING ISSUES IN CONTINUOUS CASTING OF STEEL: A PROJECT CLUSTERING EXPERIENCE IN THE EUROPEAN PROGRAMMES FRAME

Problem-solving in industrial processes relies on the adequate development and use of tools able to get insight and improved knowledge and know how on the phenomena behind the occurrence e.g, of factors affecting production quality and productivity. In steel production, this gains particular importance due to the need of following the increasingly severe market request and the unavoidable sustainability needs for producers – economic and environmental. To this scope, process control tools, supported by adequate sensoring in a digitalised and AI-based framework, are of outmost importance and increasing use.
A backbone for the process control architecture, when aimed at setting up tools for process management as digital twin working off- and online, is a reliable description of the phenomena behind the process, based on a validated modelling. In this view, continuous casting of steel shows a multi-fold approach based on single issues, as steel flow, solidification, heat transfer, behavior of oxides dispersed in steel, or integrating them into a complex and Multiphysics architecture. A significant number of these activity were funded by European programmes grants, allowing as outcome an improved knowledge enabling a more efficient development of tools supported by sensoring on-field able to process management, quality control and support decision. An example is given in this contribution, where it is shown the pivot role of modelling in continuous casting, allowing to fundamental knowledge and problem-solving (headlines of METACAST project), the approach joint to process monitoring to a definition of a digital twin for quality control minimizing defects (SUNSHINE) and another (SHELL-CRACK) where the modelling approach is used jointly with lab activities and hardware products to better drive their use and to ensure problem solving as well as regards to as-cast surface quality enhancement. All of these are funded by the European Research Fund For Coal and Steel Programme (RFCS).

Speaker: Michele De Santis (Rina Consulting - Centro Sviluppo Materiali SpA)

422 Application of Deep Learning technique to improve the scrap quality

In recent years, the exploitation of Deep Learning and computer vision to classify waste material has rapidly increased to automate recycling processes, increasing efficiency and reducing carbon footprint. Electric steelworks, which produce steel by recycling ferrous scrap, fit perfectly into this context. In effect, the identification and classification of different types of scrap is strategic to improve efficiency in steel production, promote implementation of Circular Economy principles and reduce CO2 emissions. In particular, to enhance the recycling of low-quality scrap material, it is fundamental to reduce the presence of impurities such as tramp elements (e.g. copper). Currently, scrap characterization and monitoring are still manually carried out, based on subjective assessment based on operators’ experience. Therefore, the application of Deep Learning techniques for steel scrap classification is crucial to improve scrap recycling and exemplary shows that AI can be profitably applied in the metallurgical field to automatically assess the grade of each scrap piece.
In the present work, a Deep Learning model for the automatic detection and identification of the presence of copper in scrap is described. The created dataset consists of scrap images collected with the camera during the Horizon Europe Clean Steel Partnership project entitled “Purity improvement of scrap metal” (Ref. PURESCRAP - G.A. 101092168). The images, obtained in the test campaigns conducted at Stena Recycling facility, were labelled and exploited to train, validate and test the model. In particular, two models were developed based on the FasterRCNN + ResetX-101 architecture and YOLOv11 architecture, and their performances were compared.

Speaker: Alice Petrucciani (Scuola Superiore Sant'Anna)

Primary process and preparation of the materials

2.1.1

423 BOF Technology in the 21st century - Lives declared dead - or survival of the fittest!

The transformation toward sustainable green production is focusing on hydrogen technologies and recycling of scrap.
The constraints of resources availability are known (green H2/electricity, high grade DRI, scrap volume and quality).
Therefore, the BOF process technolgoy will remain for the next 25 years the prominent technology benefitting from a couple of process advantages to overcome futures challenges:
• Economic aspects on increasing P levels will define applied process solutions with optimized slag control.
• Synthetic hot metal will require adapted process control.
• Maximised scrap rates are in contradiction to tramp element control.

Integration of digitilization approaches and applying AI/ML for process optimization will provide further performance gains.

Solutions and perspectives will be presented to keep the BOF technology fit for the future.

Speaker: Dr Jens Kempken (SMS group)

424 CAESAR HEU project - CirculArity Enhancements by low quality Scrap Analysis and Refinement

Scrap usage in steelmaking is a common practice to improve the process sustainability, as it decreases the use of virgin raw materials and boosts the circularity of the sector (decreasing CO2 emissions and energy consumption). Nevertheless, the current trend in the EU scrap market points to a slight decrease in pre-consumer scrap (E2, E6, E8, turnings..) and an increase in the short- and long-term of the post-consumer scrap stream (E1, E3, HMS…), due to an increase in steel consumption in the last 30 years. Nowadays, the latter “low-quality” scrap streams are not suitable for most applications, thus limiting their use in steelmaking. To increase the steel scrap recycling capacity and energy efficiency, while keeping the EU competitive and secured in terms of raw materials imports, energy consumption and climate change impact, innovative technologies need to be implemented to clean the scrap before it reaches the steel furnaces. The CAESAR project gathers steelmakers, technology developers and research centers in a joint effort to validate, at full-size industrial scale, integrated scrap upgrading, sorting and characterization technologies. As a result, CAESAR enables to local usage of low-quality scrap streams in Europe, while keeping a high-quality product and generating valorization routes for all the non-ferrous fractions obtained, towards a zero waste steel sector.
At this stage of the project, several interesting results have already be obtained on key topics:
• Mapping of the EU scrap market and characterization of exported low-quality grades – in particular with respect to locally consumed ones
• Selecting, testing and integrating the best available technologies to upgrade, sort and characterize lower-quality scrap
• Exploring advanced scrap cleaning and on-line characterization technologies

Speaker: Jean-Christophe Pierret (CRM Group)

425 BOF operation with increased scrap rate for CO$_{2}$-reduction

The REDERS project, which stands for "Reduced CO$_{2}$ emissions by increased recycling ratio in steelmaking processes", is a joint project of the steel producers thyssenkrupp steel Europe (tkSE) and Hüttenwerke Krupp Mannesmann (HKM) together with the recycling company TSR and the research institute BFI, which is coordinating the entire project.
The aim of the project is to increase the proportion of recycled scrap in the production of iron and steel and at the same time reduce the CO$_{2}$ emissions of integrated steel mills. To this end, a new innovative recycling plant with advanced optical detection systems and a modern material management system has been developed, built and continuously improved.
The first industrial trials of the new high-quality recycling product have been carried out at HKM's industrial BOF. In the converter, oxygen is blown into pig iron from the blast furnace, mainly to reduce the carbon content, phosphorus and nitrogen. This process produces CO$_{2}$ and also a lot of heat due to exothermic reactions. Feeding steel scrap into the process for cooling purposes is already common practice in converter operations. Further substitution of blast furnace-based hot metal by increased use of recycled material leads to a reduction in CO$_{2}$ emissions. However, the increase in the recycling rate in the converter is limited, as the input materials have too high a content of tramp elements.
The presentation will give an overview of TSR's new innovative recycling plant and present the main results of the industrial trials with increased scrap rates at HKM's BOF. An outlook on further applications will also be given.

Speaker: Dr Marten Lichte (VDEh-Betriebsforschungsinstitut GmbH)

426 Utilizing BOF/EAF Energy Recovery for Vacuum Generation in RH and VTD Type Degassers

Traditionally, RH recirculatory degassers and large vacuum tank degassers use superheated steam to generate the vacuum required for their metallurgical process. The steam is supplied, as required, to a number of steam jet pumps, which can create vacuum levels of less than one mbar absolute.
Usually, the steam for these vacuum pumps is generated either from an independent package type boiler or, from larger plant wide boilers. These boilers are often fuelled by burning gas or oil based media and hence have a significant carbon footprint.
In order to reduce the carbon emissions and the high operating costs associated with these types of boilers, there has been a move in recent times to mechanical type vacuum pumps, powered entirely by electrical energy. Whilst this solution offers a very environmentally clean method of vacuum generation, with operating costs significantly lower than those associated with steam, the capital costs of such systems can be many times greater than that for an equivalent steam pump. In addition, the space requirement for an equivalent mechanical vacuum pump system can often be prohibitive.
As an alternative to a mechanical based pump, it is also possible to utilise the excess energy created during the steelmaking process, from either the BOF or EAF, to generate the steam required to operate a steam vacuum pump. The challenges of this solution lie within the sequencing and storage of the steam, which is batch generated, and ensuring that the quality of the steam at the user is sufficient for good pumping performance and overall plant longevity.
This paper aims to describe a solution that can meet the operational steam requirements of large vacuum degassing plants, using energy recovery techniques, at a lower capital and real estate investment than that required for a mechanical vacuum pumping system.

Speaker: Mark Whitehead (SMS group)

427 Additional scrap melting capacity with dual-flow post-combustion lance at ArcelorMittal Dunkerque

Increasing the energy source in BOF process and transferring it to the bath is a potential solution for fostering scrap melting, decreasing Hot Metal Ratio and thus global CO2 emissions.
Post-combustion at BOF converter is usually around 10-12%. Many developments have been done in steelmaking industry to use this potential energy, either for the management of BOF mouth opening and skull removal or for low Hot Metal Ratio operation, but challenging issues are often reported: limited increase of the achieved post-combustion rate, or with low effectiveness for scrap melting, or excessive thermal stress for refractories and fume system.
ArcelorMittal R&D investigated several possible oxygen lance tip designs to identify promising candidate solutions with additional oxygen ports for post-combustion, changing the distance to the tip, angles, tuyeres characteristics and oxygen flow rate.
Selected designs have then been tested industrially in ArcelorMittal Dunkerque after modification of the existing single-flow oxygen lance for a double-flow control and after implementing dedicated sensors and dynamic descriptive model to evaluate and monitor the energy efficiency in real-time. The current design allows from 8 to 15 kg of extra Fe molten per ton of hot metal, with equivalent reduction of the hot metal ratio. No issue was observed for fume system or refractory wear. Ongoing work is now focusing on lance tip lifespan and reliability.

Speaker: Jean-Christophe Huber (ArcelorMittal R&D)

Process Transformation & Strategy

5.2.5

Convener: Andrea Grasselli (Tenova)

428 Complexity of decision-making process through sensitivity analysis for decarbonization technologies

The iron and steel industry contributes significantly to global greenhouse gas emissions, accounting for 7.2% of the total. The predominant BF-BOF ironmaking route, responsible for 70% of global pig iron production, is primarily coal-based, posing substantial challenges for decarbonization. As steel industry stakeholders strive to reduce carbon footprints while maintaining economic viability, the transition from coal to alternative energy sources such as electricity, natural gas, and hydrogen becomes imperative. However, these alternatives often entail higher and more volatile costs, influenced by regional factors and market dynamics. Furthermore, uncertainties persist regarding the future availability and pricing of critical raw materials like steel scraps and high-grade pellets (Fe > 67%) and of green energies like hydrogen.
To address these complexities, the SMS plant assessment tool offers a robust framework for evaluating the carbon footprint, energy consumption, and operating costs of integrated steel plants based on various configurations. This tool enables the simulation of diverse decarbonization pathways, allowing stakeholders to predict key performance indicators (KPIs) under varying regional conditions, including energy and raw material prices and CO2 certificate costs. By conducting sensitivity analyses, the tool identifies resilient decarbonization strategies that minimize economic impact.
The application of the SMS plant assessment tool across different steel industry challenges demonstrates its efficiency in formulating optimal decarbonization roadmaps. Sensitivity analyses further enhance this process by assessing the robustness of proposed strategies against fluctuating market conditions. This methodology provides a comprehensive approach to navigating the complexities of the decision-making process for decarbonization, ensuring sustainable and economically feasible outcomes for the steel industry.

Speaker: Georges Stamatakis (SMS group)

429 Logistics Simulation for the Green Steel Transition: Optimizing Production and Sustainability

The transition to carbon-free steel production presents significant challenges for the industry. Adapting to new processes, production routes, and logistics is a central aspect of this transformation. Particularly notable is the shift from traditional Blast Furnace (BF) / Basic Oxygen Furnace (BOF) route to electric steelmaking route. This change requires not only a comprehensive restructuring in secondary metallurgy but also significant modifications to the primary equipment, disrupting established workflows. Additionally, production facilities need to be reconfigured for new material flows such as scrap, pig iron, hot metal, DRI (Direct Reduced Iron), and HBI (Hot Briquetted Iron).
To make these transition processes more efficient, logistics simulations are used. These helps optimize processes in melt shops and adjacent areas, such as scrap yards, and specifically support investments that facilitate the transition to electric steel production.
A particular focus is on simulating transport logistics to facilitate the integration of an electric arc furnace into existing BOF melt shop. A practical example of these challenges and solutions is provided by the case study of voestalpine in Linz, which serves as a model for the successful implementation of such processes.

Speaker: Stefan Mühlböck (Primetals Technologies GmbH)

430 How can Life Cycle Assessment support the definition of decarbonization strategies: lessons learnt from the GreenHeatEAF project

Life Cycle Assessment (LCA) is the most widely used methodology to quantify the potential environmental impact of the steelmaking industry, but it can been used to support the investigation of decarbonization strategies in the steel sector.
In this contribution we aim to illustrate how LCA can be used to support the decision-making process within the context of GreenHeatEAF “Gradual Integration of REnewable carbon and alternative non-carbon Energy sources and modular HEATIing technologies in EAF for progressive CO2 decrease” project, funded within the Horizon Europe programme.
Within GreenHeatEAF, the aim is to investigate alternative decarbonization strategies in the Electric Arc Furnace (EAF) process, by means of three options:
• Integration of non-fossil gases flows, which test the use of hydrogen in different blends,
• Fossil C-sources replacement with biomass/biochar;
• Modular and alternative heat recovery, through off-gas or slags.

LCA and Life Cycle Costing (LCC) methods are used in the GreenHeatEAF project to assess the environmental and economic performance of the melting process to evaluate the impact after the implementation of developed scenarios and to be compared to a baseline scenario.
The baseline scenario has been defined for four case studies, including both EAF and Blast Furnace-Basic Oxygen Furnace (BF-BOF) routes and the preliminary results of the LCA have shown that relevant impact categories throughout all four case studies are climate change and fossil resources use. Depending on the baseline technology, impacts on climate change range from a minimum value of 306,5 kg CO2eq/ton of steel to a maximum value of 2.486 kg CO2eq/ton of steel. The relevance of production processes to significant impact categories varies depending on the production technology. Results show that EAF is a common environmental hotspot due to electricity consumption and direct CO2 emissions, demonstrating the importance of the solutions suggested and tested by the present project.

Speaker: Francesca Albano

431 Optimizing Decarbonization Processes: From Iron Ore to Steel

As part of the decarbonization process in the steelmaking industry, the direct reduction of iron ores, the use of green hydrogen as an energy source and/or the application of carbon capture technologies are crucial for achieving carbon neutrality. The study will underscore the importance of laboratory material testing and process simulation tools in determining the optimal and most feasible routes for various energy mixes and raw materials. Additionally, in light of the rising demand for DR-grade pellets, a significant gap is emerging between future DR-grade raw material demand and cost-efficient material supply.
An optimized plant concept necessitates a comprehensive review of the entire production route, from the iron ore mine to crude steel. This includes key stages such as beneficiation, pelletizing, direct reduction, and steelmaking (EAF / Smelter+BOF), as well as the possibilities for process integration, e.g. between pelletizing and direct reduction plant. It also provides the necessary information to determine whether the EAF or Smelter+BOF is the optimal steelmaking technology based on raw materials available. Primetals has developed simulation tools to provide essential data for consumption figures, economic validation, influences on product quality and CO2 intensity.
By utilizing simulation tools, laboratory tests such as pellet pot tests, reduction tests, melting tests and extensive process know-how, it is possible to optimize the entire production chain from the mine to steelmaking.

Speaker: Dr Oday Daghagheleh (Primetals Technologies Linz GmbH)

432 Modularization strategy for the construction of Direct Reduction Plants

Decarbonization of the steel industry has multiplied the number of projects involving construction of a direct reduction plant.
Shorter project schedules and avoiding cost/availability issues with onsite construction skilled workers are key advantages of a modularized construction strategy.
TECNICAS REUNIDAS has executed projects in other industrial areas using this strategy and has conducted detailed analysis for DR plants in early project phases.
Modularization of the DRI unit could be split into 4 main elements:
-DRI reactor structure:Main element of the plant in size and complexity. Its dimensions (25m x 25m) are an important factor that affect the feasibility of its potential modularization. A detailed road survey shall be executed to determine the maximum transport dimensions.
Installation method, normally using a super HL crane (usually ringer type), with low availability in the market and to be booked a long time in advance, is an important constraint and requires a project decision at an early stage.
-Process Gas Heater (PGH): could be supplied modularized directly by the OEM, implying an important reduction of construction manhours at the Site. On the other hand, a detailed comparison analysis is required between the modular and the stick-built options.
-Rest of the plant could be modularized more simply:
Piperacks – PARs
Process structure – PAUs
Hytemp Tower – PAUs
Hytemp Bridge – PARs
Modules’ size and dimensions will be determined by the maximum transport envelope defined in the road survey and the installation method (crane, SPMT, jacking…).
E-Houses: Modularization could include supply of the electrical substation and control room, mostly using a specialized vendor but could also be fabricated by the module yard.
In summary, the degree of modularization can be very high in this type of plant, with major gains for the project, but shall consider important constraints related to site access and installation method.

Speaker: Mr Juan Garcia Jimenez

Smelting & Carburization Technologies

1.4.4

Convener: F Cirilli (Rina Consulting Centro Sviluppo Materiali)

433 Smelter technology to close the raw material gap in green steel production routes

The transition to green steel faces several challenges: raw material availability, green electric energy availability, and the associated cost. Direct reduction (DR) is a promising solution for reducing CO2 emissions in ironmaking. While natural gas-based DR is established and new plants are ready for operation with green hydrogen, the high costs of natural gas and hydrogen in Europe increase operational expenses. Additionally, most iron ore available and currently used in BFs is of medium to lower grade with high gangue content, resulting in high slag amounts if processed in established DR – EAF route.
Electric arc furnaces (EAFs) focus on melting, final reduction and refining of direct reduced iron (DRI) made from high-grade ores with low gangue content. However, the availability of such high-grade ores is limited and lower grade ores with high gang content limit EAF productivity, increase yield losses, and raise consumption figures. Hence, a two-step process combining an electric smelting furnace (Smelter) with a BOF converter offers a more efficient solution. The Smelter's reducing conditions and long residence times allow efficient processing of DRI from low-grade ores, maintaining high iron yield and producing slag suitable for the cement industry. Refining in the BOF converter keeps existing steel plant processes and logistics unchanged, eliminating the need for re-certification.
The Smelter can be combined with natural gas or hydrogen-based DR plants and can handle different DRI sizes, from briquettes to pellets and fines. This paper compares different DR plants in combination with EAF or Smelter and BOF regarding CO2 emissions and energy demand. It discusses the influence of DRI carbon content and metallization degree on EAF and Smelter productivity, consumption, and CO2 emissions, and provides an overview of Smelter process validation tests with various DRI compositions and sizes.

Speaker: Bernhard Voraberger (Primetals Technologies)

434 Slag Modelling and Design Optimisation for Enhanced Performance in Electric Smelting Furnaces

The ironmaking industry faces increasing pressure to reduce carbon emissions in response to global sustainability initiatives. This has incentivised steelmakers to move away from the traditional Blast Furnace (BF), with an emerging alternative being the Electric Smelting Furnace (ESF). The transition to ESFs will reshape slag management and design, requiring a reassessment of slag properties, such as liquidus and viscosity, and elevating electrical conductivity to a key design parameter. The decline in BF slag production also creates an opportunity for ESF slags to supply the cement industry.
This paper presents a methodology to develop an operating window for optimising slag design based on critical slag properties and evaluates selected slag compositions within this framework. The analysis examines the impact of these slags on raw material consumption, energy use, furnace integrity, and operational costs. It ultimately proposes slag designs that enhance ESF performance by promoting high production intensity and improved impurity distribution. Strategies are also explored to ensure ESF slags meet the requirements for cement production, supporting sustainability in both the ironmaking and cement industries.

Speaker: Kamal Joubarani (Hatch Ltd.)

435 Investigation of the smelting and carburization behavior of DRI-Pellets under an inert atmosphere using various carburization agents.

Carburization during the smelting of direct reduced iron in a smelter is critical in achieving the desired hot metal properties for refining in a steel plant. This study investigates DRI's smelting and carburizing behavior, focusing on the interaction between slag and carburization agents of differing grain sizes. The key objectives include achieving a high carbon content in the hot metal, examining the dissolution behavior of carbon in DRI-based smelts, and maintaining a specific slag basicity. The effects of increasing slag heights and element interactions on carbon dissolution were also analyzed. The experiments were conducted using a 60 kW vacuum induction furnace under an inert atmosphere at a constant pressure of 0.9 bar. A comprehensive setup allows semicontinuous material feeding, sample extraction, and video documentation of smelt behavior. Neutral-gas-reduced-DRI pellets were combined and charged with various carburization agents and lime in a base smelt with 2 weight-% carbon. The carburization agents include lignite coke, coke breeze, and bio-based carbon in 4–2 mm grain sizes and 2–1 mm. Analysis of the samples and the regulus showed an average carbon content of 4 weight-% in the regulus. The increasing slag volume influenced both the dissolution behavior of the carburization agents and the DRI. A pressure increase in the furnace chamber, attributed to CO/CO2 generation during reduction, was managed through repeated evacuations. The target slag basicity wasn’t achieved due to elevated MgO content from crucible materials and insufficient reaction time. The findings underline critical best practices in optimizing carbon dissolution and slag management. The results visualize strategies for producing high-quality DRI-based hot metal.

Speaker: Mr Daniel Kipp (Universität Duisburg-Essen)

436 Reaction behaviour of different carbon sources in FeO containing slags for electric smelting furnaces

Electric smelting furnaces (ESF) represent a promising ironmaking technology for reducing steel industry’s CO2 emissions by utilizing direct reduced iron and a lower need of solid carbon sources compared to blast furnaces. Carbon sources in ESFs serve two primary functions: reduction of FeO from slag and acting as carburizers for the hot metal. Thus, the yield of ESFs is strongly influenced by their reaction behavior and density, with biogenic options (biochar) playing a key role in advancing sustainability. However, carbon carrier performance is influenced by reactivity, which depends on volatile matter, specific surface area (SSA), porosity and fixed carbon content. This study compares biogenic and fossil carbon sources to evaluate if biochars can outperform traditional carbon carriers in reduction behavior. Lab-scale submerging trials in 15 % FeO slag were conducted at 1550 °C to investigate the reaction behavior of biogenic (biochar from wood chips, wood coal pellets) and fossil-based (coke, anthracite) materials. Higher FeO contents can be locally present in the process zone of ESFs. Therefore, the FeO content in the used slag, recalculated from an ESF slag, was increased to ensure a sufficient FeO gradient and better highlight the reaction behavior.
The investigations indicate a faster reaction behavior with increased gas bubble size for biochar. Additional BET N2-SSA measurements revealed an increasing order of wood coal pellets (1.23 m2 g-1) < coke (2.54 m2 g-1) < anthracite (9.07 m2 g-1) < wood chips (273.71 m2 g 1), implying that biochar may have a higher reactivity. Wood pellets showed a lower SSA due to their compacted form compared to the particle form of other tested carriers. Biochars have the potential to maintain or even improve ESF yields. Nevertheless, understanding their behavior in metallurgical processes is essential for their integration into future ironmaking, offering a sustainable alternative to fossil carbon sources

Speaker: Mr Johann Winkler

437 Effect of Carbonaceous Material Graphitization Degree on Carburization Behavior in Fe-C Mixture Powder during Rapid Heating

Although carburization is one of the key reactions in steel production, and one for which no other elements can be substituted, coal as carbon source is used. Therefore, it is required to switch from coal to carbon-neutral materials for decarbonization. Previous research has reported that carbonaceous material with low graphitization degree and less ash has advantage for carburization reaction. Biochar, such as charcoal and bamboo charcoal, is a carbon-neutral material with low graphitization degree and low ash content. In this study, the effect of the graphitization degree of biochar on carburization behavior in the charcoal-iron mixture powder during rapid heating was investigated.
Biochar and graphite were prepared as carbon samples. To vary the carbon crystal structure of the biochar, it was heated in Ar atmosphere at 1450 degree C for 30 min. The crystallinity of the charcoal samples was determined with Raman spectroscopy. Spectra obtained by the Raman spectrometer show imperfections in the carbon crystal structure. IV/IG, the index of imperfections in the carbon crystal structure, was measured. The IV/IG values of graphite, biochar with heat treatment, and biochar without heat treatment are 0.02, 0.3, 0.4, respectively.
The experiments were carried out using a laser microscope equipped with an infra-red image heating furnace. Samples heated up to 1000 degree C in 1 minute, and then to 1500 degree C with 100 degree C/min. The experimental results showed that samples with the bigger IV/IG values tended to be well-carburized. Direct observation results during heating up indicated that the graphite sample showed a lower temperature of initial Fe-C melt formation than the biochar samples. It could be thought that the ash in the biochar sample affected the initial Fe-C melt formation.

Speaker: Ayana Ono (Kyushu University Graduate School of Engineering)

15:20 Closing session