Search Results (25)

The 1.9 billion metric tons of steel globally manufactured in 2023 justify the steel industry’s pivotal role in modern society’s growth. Considering the rapid development of countries that have not fully taken part in the global market, such as Africa, steel production is expected to increase in the next decade. However, the environmental burden associated with steel manufacturing must be mitigated to achieve sustainable production, which would align with the European Green Deal pathway. Such a burden is associated both with the GHG emissions and with the solid residues arising from steel manufacturing, considering both the integrated and electrical routes. The valorisation of the main steel residues from the electrical steelmaking is the central theme of this work, referring to the steel electric manufacturing in the Dalmine case study. The investigation was carried out from two different points of view, comprising the action of a plasma electric reactor and a RecoDust unit to optimize the recovery of iron and zinc, respectively, being the two main technologies envisioned in the EU-funded research project ReMFra. This work focuses on those preliminary steps required to detect the optimal recipes to consider for such industrial units, such as thermodynamic modelling, testing the mechanical properties of the briquettes produced, and the smelting trials carried out at pilot scale. However, tests for the usability of the dusty feedstock for RecoDust are carried out, and, with the results, some recommendations for pretreatment can be made. The outcomes show the high potential of these streams for metal and mineral recovery. Full article

Amid escalating global climate crises and the urgent imperative to meet the Paris Agreement’s carbon neutrality targets, the steel industry—a leading contributor to global greenhouse gas emissions—confronts unprecedented challenges in driving sustainable industrial transformation through innovative low-carbon steelmaking technologies. This paper examines decarbonization technologies across three stages (source, process, and end-of-pipe) for two dominant steel production routes: the long process (BF-BOF) and the short process (EAF). For the BF-BOF route, carbon reduction at the source stage is achieved through high-proportion pellet charging in the blast furnace and high scrap ratio utilization; at the process stage, carbon control is optimized via bottom-blowing O₂-CO₂-CaO composite injection in the converter; and at the end-of-pipe stage, CO₂ recycling and carbon capture are employed to achieve deep decarbonization. In contrast, the EAF route establishes a low-carbon production system by relying on green and efficient electric arc furnaces and hydrogen-based shaft furnaces. At the source stage, energy consumption is reduced through the use of green electricity and advanced equipment; during the process stage, precision smelting is realized through intelligent control systems; and at the end-of-pipe stage, a closed-loop is achieved by combining cascade waste heat recovery and steel slag resource utilization. Across both process routes, hydrogen-based direct reduction and green power-driven EAF technology demonstrate significant emission reduction potential, providing key technical support for the low-carbon transformation of the steel industry. Comparative analysis of industrial applications reveals varying emission reduction efficiencies, economic viability, and implementation challenges across different technical pathways. The study concludes that deep decarbonization of the steel industry requires coordinated policy incentives, technological innovation, and industrial chain collaboration. Accelerating large-scale adoption of low-carbon metallurgical technologies through these synergistic efforts will drive the global steel sector toward sustainable development goals. This study provides a systematic evaluation of current low-carbon steelmaking technologies and outlines practical implementation strategies, contributing to the industry’s decarbonization efforts. Full article

Against the backdrop of global energy crises and climate change, the iron and steel industry, as a typical high energy consumption and high-emission sector, faces rigid constraints for energy conservation and emission reduction. This paper systematically reviews the research progress and application effects of energy-saving technologies across the entire steel production chain, including coking, sintering, ironmaking, steelmaking, continuous casting, and rolling processes. Studies reveal that technologies such as coal moisture control (CMC) and coke dry quenching (CDQ) significantly improve energy utilization efficiency in the coking process. In sintering, thick-layer sintering and flue gas recirculation (FGR) technologies reduce fuel consumption while enhancing sintered ore performance. In ironmaking, high-efficiency pulverized coal injection (PCI) and hydrogen-based fuel injection effectively lower coke ratios and carbon emissions. Integrated and intelligent innovations in continuous casting and rolling processes (e.g., endless strip production, ESP) substantially reduce energy consumption. Furthermore, the system energy conservation theory, through energy cascade utilization and full-process optimization, drives dual reductions in comprehensive energy consumption and carbon emission intensity. The study emphasizes that future advancements must integrate hydrogen metallurgy, digitalization, and multi-energy synergy to steer the industry toward green, high-efficiency, and low-carbon transformation, providing technical support for China’s “Dual Carbon” goals. Full article

In this study, the carbon footprint of a steel-based windshield reinforcement component assembled in a sport utility vehicle was calculated in three different stages: steelmaking, stamping, and middle-of-use. Possible solutions to decrease carbon emissions were evidenced, such as the purchasing of steel made through low-impact technologies and the exploitation of the green energy grid to power up stamping machines. The life cycle assessment methodology was used to calculate the carbon footprint. Four different steels provided by different suppliers were compared in order to highlight the greenest material for both the steelmaking and stamping processes and the best supplier from an environmental point of view. In addition, the carbon footprint related to the component weight in vehicles with different traction set-ups, i.e., internal combustion engine, mild hybrid electric, and battery electric, was reported. To reduce the carbon footprint, electric arc furnace-based steelmaking and cold stamping were the best options. In addition, component weight reduction (for instance, changing materials) allowed a decrease in fuel and/or energy consumption, with carbon footprint benefits. Full article

Accurately assessing carbon emissions from recycling scrap steel is essential for reducing emissions in the steel industry, especially in China, the world’s largest crude steel producer. In this study, a carbon emission reduction index was introduced to evaluate the effectiveness of recycling scrap steel in reducing emissions. The index considers the three processes used in scrap steel recycling: blast furnace ironmaking, converter steelmaking, and electric arc furnace steelmaking. This study developed an evaluation model using fuzzy analytic hierarchy process and iterative cluster analysis to determine the reduction of carbon emission. From a life cycle perspective, this study identified primary factors contributing to emissions, including fuel, raw materials, electric energy, and auxiliary materials. Then, the carbon emission reduction index for scrap recycling was developed by examining the production of one ton of steel and each additional ton of scrap steel, which can provide valuable insights into the environmental impact of scrap recycling. Finally, the study forecasts the future Carbon Emission Reduction Index for steel scrap recycling. The study indicates an increase in the carbon emission reduction index for scrap recycling prior to 2017, followed by a decrease about 11.8% from 2017 to 2018 and increases from 2018 to 2021. Finally, it dropped by 8.7% per cent in 2022. Similarly, the carbon emission reduction index for electric furnace steelmaking increased prior to 2019, then subsequently decreased. It is changing by ten per cent a year. Additionally, the scrap recycling index experienced a significant decrease of 90% in 2015, followed by a gradual increase until 2017 and then a consistent decrease every year thereafter. The index suddenly rose in 2021 and then decreased change for policy reasons. The forecast results suggest a gradual increase in the carbon emission reduction index per ton of steel scrap in the future. In conclusion, the practicable modeling methodology has the ability to assist government organizations and private enterprises in devising efficient green and low-carbon development tactics. Full article

In the context of carbon reduction and emission reduction, the new process of electric arc furnace (EAF) steelmaking based on direct hydrogen reduction is an important potential method for the green and sustainable development of the steel industry. Within an electric furnace for the hydrogen-based direct reduction of iron, after hydrogen-based directly reduced iron (HDRI) is produced through a shaft furnace, HDRI is melted or smelted in an EAF to form final products such as high-purity iron or high-end special steel. As smelting proceeds in the electric furnace, it is easy for pieces of HDRI to bond to each other and become larger pieces; they may even form an “iceberg”, and this phenomenon may then worsen the smelting working conditions. Therefore, the melting of HDRI is the key to affecting the smelting cycle and energy consumption of EAFs. In this study, based on the basic characteristics of HDRI, we established an HDRI melting model using COMSOL Multiphysics 6.0 and studied the HDRI melting process, utilizing pellets with a radius of 8 mm. The results of our simulation show that the HDRI melting process can be divided into three different stages: generating a solidified steel layer, melting the solidified steel layer, and melting HDRI bodies. Moreover, multiple HDRI processes are prone to bonding in the melting process. Increasing the spacing between pieces of HDRI and increasing the preheating temperature used on the HDRI can effectively reduce the aforementioned bonding phenomenon. When the melting pool temperature is 1873 K, increasing the spacing of HDRI to 10 mm and increasing the initial HDRI temperature to 973 K was shown to effectively reduce or eliminate the bonding phenomenon among pieces of HDRI. In addition, with the increase in the melting pool temperature, the time required for melting within the three stages of the HDRI melting process shortened, and the melting speed was accelerated. With the increase in the temperature used to preheat the HDRI, the duration of the solidified steel layer’s existence was also shortened, but this had no significant impact on the time required for the complete melting of HDRI. This study provides a theoretical basis for the optimization of the HDRI process within EAFs. Full article

The steel industry, which relies heavily on primary energy, is one of the industries with the highest CO₂ emissions in China. It is urgent for the industry to identify ways to embark on the path to “green steel”. Hydrogen metallurgy technology uses hydrogen as a reducing agent, and its use is an important way to reduce CO₂ emissions from long-term steelmaking and ensure the green and sustainable development of the steel industry. Previous research has demonstrated the feasibility and emission reduction effects of hydrogen metallurgy technology; however, further research is needed to dynamically analyze the overall impact of the large-scale development of hydrogen metallurgy technology on future CO₂ emissions from the steel industry. This article selects the integrated MARKAL-EFOM system (TIMES) model as its analysis model, constructs a China steel industry hydrogen metallurgy model (TIMES-CSHM), and analyzes the resulting impact of hydrogen metallurgy technology on CO₂ emissions. The results indicate that in the business-as-usual scenario (BAU scenario), applying hydrogen metallurgy technology in the period from 2020 to 2050 is expected to reduce emissions by 203 million tons, and make an average 39.85% contribution to reducing the steel industry’s CO₂ emissions. In the carbon emission reduction scenario, applying hydrogen metallurgy technology in the period from 2020 to 2050 is expected to reduce emissions by 353 million tons, contributing an average of 41.32% to steel industry CO₂ reduction. This study provides an assessment of how hydrogen metallurgy can reduce CO₂ emissions in the steel industry, and also provides a reference for the development of hydrogen metallurgy technology. Full article

The steelmaking industry is responsible for 7% of global CO₂ emissions, making decarbonization a significant challenge. This review provides a comprehensive analysis of current steel-production processes, assessing their environmental impact in terms of CO₂ emissions at a global level. Limitations of the current pathways are outlined by using objective criteria and a detailed review of the relevant literature. Decarbonization strategies are rigorously evaluated across various scenarios, emphasizing technology feasibility. Focusing on three pivotal areas—scrap utilization, hydrogen integration, and electricity consumption—in-depth assessments are provided, backed by notable contributions from both industrial and scientific fields. The intricate interplay of technical, economic, and regulatory considerations substantially affects CO₂ emissions, particularly considering the EU Emissions Trading System. Leading steel producers have established challenging targets for achieving carbon neutrality, requiring a thorough evaluation of industry practices. This paper emphasizes tactics to be employed within short-, medium-, and long-term periods. This article explores two distinct case studies: One involves a hot rolling mill that utilizes advanced energy techniques and uses H₂ for the reheating furnace, resulting in a reduction of 229 kt CO₂-eq per year. The second case examines DRI production incorporating H₂ and achieves over 90% CO₂ reduction per ton of DRI. Full article

Steelmaking and ferrous metal processing companies are suppliers of great importance to a wide array of industries, thus being quintessential for the social and financial growth of regions and countries. Most used processes (i.e., blast furnace, basic oxygen furnace, and electric arc furnace-based) are, however, highly pollutant, generating hazardous wastes that were usually landfilled. Generated wastes are important sources of secondary raw materials such as zinc and iron, presenting interesting market value. Hence, aiming to develop green procedures, industries have been using diverse approaches to treat and detoxify hazardous wastes, extract and reuse added value components, or even use their existing infrastructures to convert the wastes generated by other industries into secondary raw materials for steel manufacturing. This paper reviews the main industrial processes, focusing on the waste-generating steps, and discloses the most recent and relevant industrial synergies toward a circular economy. The final contribution of this study consists of the compilation of industrial synergies and recovery technologies for the steelmaking and metal processes. Full article

Converter blowing limestone powder making slag steelmaking process has the advantages of low carbon and high efficiency, and can realize the resource utilization of CO₂ in the metallurgical process, which is in line with the development direction of green metallurgy. Based on a thermogravimetric-differential thermal analyzer, the kinetic mechanism of decomposition of small limestone at steelmaking temperatures was investigated by a modified double extrapolation method. The results showed that with a higher rate of heating, limestone decomposition lagged, and decomposition temperature increased. Furthermore, the smaller the limestone particle size, the lower the activation energy of decomposition. Compared with N₂, air, and O₂, small limestone powder used for converter blowing could complete more rapid decomposition, and the time required for decomposition shortened by about 1/3, although the decomposition temperature increased in the CO₂. The limestone decomposition rate increased and then decreased at low to high CO₂ partial pressures. With a limiting link, the inhibition was more significant under high CO₂ partial pressure, but the reaction can be fully completed by 1000 °C. The decomposition type modeled was stochastic nucleation and subsequent growth. As the partial pressure of CO₂ increased from 25% to 100%, the number of reaction stages, n, increased. Full article

The transformation from traditional iron- and steelmaking technologies to green H₂-based new technologies will require an improvement in the quality and purity of iron ore burden materials. Iron ore pellets are essential inputs for producing direct reduced iron (DRI), but the conventional binders, used in iron ore pelletizing, introduce gangue oxides to the DRI and consequently increase the slag generation and energy consumption in the steelmaking unit. Partial and/or full replacement of the traditional binders with novel organic binders would significantly contribute to improving the process efficiency, particularly in the next-generation H₂-based direct reduction technology. This study illustrates the feasibility of pelletizing magnetite iron ore concentrate using four organic binders: KemPel, Alcotac CS, Alcotac FE16, and CMC, in comparison to bentonite as a reference. The study explores the influence of binder type, binder dosage, and moisture content on the characteristics and properties of the pellets. The efficiency of binders was characterized by the moisture content, drop number test, cold compression strength, and H₂ reduction of pellets. For dry pellets, CMS was superior among other binders including bentonite in developing dry strength. After firing, the pellets produced by the partial replacement of bentonite with 0.1 wt.% KemPel demonstrate a performance nearly identical to the reference pellets. While the complete replacement of bentonite with organic binder shows a lower performance of fired pellets compared to the reference, it may still be suitable for use in DR shaft furnaces. The cold-bonded pellets demonstrate a superior reduction rate compared to fired pellets. Full article

Because of incomplete recycling resource management and technology development, inorganic sludge and slag has been misused in Taiwan. The recycling of inorganic sludge and slag is a pressing crisis. Resource materials with a sustainable use value are misplaced and have a significant impact on society and the environment, which greatly reduces industrial competitiveness. To solve the dilemma of EAF oxidizing slag recycled from the steel-making process, it is important to find solutions to improve the stability of EAF oxidizing slags based on the innovative thinking of the circular economy. We can improve the value of recycling resources and solve the contradiction between economic development and environmental impact. The project team intends to investigate the development and application of reclaiming EAF oxidizing slags blended with fire-retardant materials, which will integrate R&D work from four different aspects. First, a verification mechanism is carried out to establish stainless steel furnace materials. Suppliers must be assisted in conducting quality management for EAF oxidizing slags to ensure the quality of the materials provided. Next, high-value building materials must be developed using slag stabilization technology, and fire-retardant tests must be conducted on the recycled building materials. A comprehensive evaluation and verification of the recycled building materials must be undertaken, and high-value green building materials must be produced with fire-retardant and sound-proofing characteristics. Integration with national standards and regulations can drive the market integration of high-value building materials and the industrial chain. On the other hand, the applicability of existing regulations to facilitate the legal use of EAF oxidizing slags will be explored. Full article

The European steel industry is experiencing new challenges related to the market situation and climate policy. Experience from the period of pandemic restrictions and the effects of Russia’s armed invasion of Ukraine has given many countries a basis for including steel along with raw materials (coke, iron ore, electricity) in economic security products (CRMA). Steel is needed for economic infrastructure and construction development as well as a material for other industries (without steel, factories will not produce cars, machinery, ships, washing machines, etc.). In 2022, steelmakers faced a deepening energy crisis and economic slowdown. The market situation prompted steelmakers to impose restrictions on production volumes (worldwide production fell by 4% compared to the previous year). Despite the difficult economic situation of the steel industry (production in EU countries fell by 11% in 2022 compared to the previous year), the EU is strengthening its industrial decarbonisation policy (“Fit for 55”). The decarbonisation of steel production is set to accelerate by 2050. To sharply reduce carbon emissions, steel mills need new steelmaking technologies. The largest global, steelmakers are already investing in new technologies that will use green hydrogen (produced from renewable energy sources). Reducing iron ore with hydrogen plasma will drastically reduce CO₂ emissions (steel production using hydrogen could emit up to 95% less CO₂ than the current BF + BOF blast furnace + basic oxygen furnace integrated method). Investments in new technologies must be tailored to the steel industry. A net zero strategy (deep decarbonisation goal) may have different scenarios in different EU countries. The purpose of this paper was to introduce the conditions for investing in low-carbon steelmaking technologies in the Polish steel market and to develop (based on expert opinion) scenarios for the decarbonisation of the Polish steel industry. Full article

The utilization of end-of-life batteries (including Zn-C and alkaline batteries) is one of the areas that need to be perfected in order to provide environmental and human safety as well as to contribute to closing the material loop, as described in the EU Green Deal. The presented study shows the environmental impacts of the two selected pyrometallurgical technologies (processing of the black mass from waste Zn-C and alkaline batteries as an additive to an existing process of the recycling of steelmaking dust and treatment of the black mass as the primary waste material, both processes performed in a Waelz kiln). The presented LCA-based study of the recycling of end-of-life Zn-C and alkaline batteries focused on terrestrial ecotoxicity can be a useful tool in the process of the development of a circular economy in Europe, as it provides a multi-disciplinary overview of the most important environmental loads associated with the described recycling technologies. Therefore, the goal of the presented study was to compare the environmental performance (utilizing LCA) of two different metallurgical processes of black mass utilization, i.e., the conventional method utilizing black mass as a co-substrate and the newly developed method utilizing black mass as a primary substrate. Full article

During the converter steelmaking process, gas-slag-metal three-phase emulsification is realized by injecting gas to complete metallurgical tasks such as slagging, dephosphorization, decarburization, and heating. As green and intelligent development of the steel industry progresses, converter steelmaking injection technology is also constantly innovating. In this review, the types and applications of top blowing injection elements, bottom blowing injection elements, and injection the medium are reviewed. Three different types of combined blowing processes are compared. At the same time, the advantages and disadvantages of different bottom blowing elements and injection media are respectively discussed. Finally, based on the research and application status of converter injection technology, the development direction of converter steelmaking injection technology is discussed. Accelerating the innovation of converter steelmaking injection technology, especially the improvement and breakthrough of high efficiency, reductions the environmental burden, and long life technology, will play an important role in promoting the transformation and improvement of the steel industry. Full article