Residue Valorization in the Iron and Steel Industries: Sustainable Solutions for a Cleaner and More Competitive Future Europe

Abstract

The steel industry is an important engine for sustainable growth, added value, and high-quality employment within the European Union. It is committed to reducing its CO2 emissions due to production by up to 50% by 2030 compared to 1990′s level by developing and upscaling the technologies required to contribute to European initiatives, such as the Circular Economy Action Plan (CEAP) and the European Green Deal (EGD). The Clean Steel Partnership (CSP, a public–private partnership), which is led by the European Steel Association (EUROFER) and the European Steel Technology Platform (ESTEP), defined technological CO2 mitigation pathways comprising carbon direct avoidance (CDA), smart carbon usage SCU), and a circular economy (CE). CE approaches ensure competitiveness through increased resource efficiency and sustainability and consist of different issues, such as the valorization of steelmaking residues (dusts, slags, sludge) for internal recycling in the steelmaking process, enhanced steel recycling (scrap use), the use of secondary carbon carriers from non-steel sectors as a reducing agent and energy source in the steelmaking process chain, and CE business models (supply chain analyses). The current paper gives an overview of different technological CE approaches as obtained in a dedicated workshop called “Resi4Future—Residue valorization in iron and steel industry: sustainable solutions for a cleaner and more competitive future Europe” that was organized by ESTEP to focus on future challenges toward the final goal of industrial deployment.

Recovery of Waste with a High Iron Content in the Context of the Circular Economy

“…The results of the optimization problem (11) are presented in Table 5. The response area (13) and related contour lines are shown in Figure 14 for the average value of parameter x 2 . The response surface that shapes the crushing range y 3 according to parameters: x 1 -ferrous sludge; x 2 -sludge mill scale; x 3 -sintering sludge, has the expression:…”

“…By using simple processing operations of this small and powdery waste (agglomeration, pelleting, briquetting [ 9 , 10 , 11 , 12 , 13 , 14 , 15 ]), by-products can be obtained and can be used in the steel industry, when developing cast iron (agglomerates, pellets) or steel (reduced agglomerates, metallic pellets, lighters with adequate mechanical strength– Figure 1 ). The condition that these products can be recovered in the steel industry is not to pollute cast iron or steel with residual elements such as Zn, Cu, Sn, Cr, Ni.…”

“…If, through the repeated recycling of this waste, there is an increase in the content of residual elements, which would lead to the contamination of cast iron/steel, there must be applied methods of reducing the content of these elements [ 16 , 17 , 18 ] or this waste should be recovered by other industries and not by steel industry [ 13 , 19 , 20 ].…”

A New Methodological Approach on the Characterization of Optimal Charging Rates at the Hydrogen Plasma Smelting Reduction Process Part 2: Results

“…In 2019, the EU28 produced 158.8 million tonnes of crude steel, of which 59.1% (93.9 million tonnes) was made via the integrated route (blast furnace-basic oxygen furnace) with specific estimated emissions of 1.85 t CO 2 /t steel and 40.9% (64.9 million tonnes) via the electric arc (EAF) route. Due to these emission levels, the iron and steel industry must develop new low-carbon technologies to meet the required greenhouse gas targets [1][2][3][4]. To further secure the steel production in Europe, the companies are focusing on two technological routes to reduce the CO 2 emissions in the steel sector: Smart Carbon Usage (SCU) and Carbon Direct Avoidance (CDA).…”

High-Performance Method of Recovery of Metals from EAF Dust—Processing without Solid Waste

“…The dust constitutes between 1 and 2% of the batch intended for melting [1,2]. As per [2,3] average annual steel production is 1600 million tons, of which 33% is produced in an electric arc furnace (EAF). This means that an annual output of 5 to 10 million tons EAF dust is generated.…”