Work

Multi-material injection system to foster circularity: Valorization of recycled polymers from waste plastics in electric arc furnace

Year: 2025

Type: article

Abstract: • Coal injected in EAF for slag foaming can be successfully substituted with a new material derived from plastic residue. • Material compliance with the Technical Standard UNI 10667–17 ensures the material quality, as well as its physical characteristics and environmental performances. • A tailored injection system is fundamental to obtain optimal slag foaming. • LCA study supports the coal substitution with the new material. Alternative materials able to replace fossil carbon sources is a topic of great interest among European steel mills. The OnlyPlastic project, funded by the Research Fund for Coal and Steel (RFCS), aims to demonstrate the feasibility of substituting fossil carbon in EAF-based steel production with a new SRA derived from plastic residues, compliant with UNI 10667–17 and produced by I.BLU. Such approach avoids landfill disposal of hard-to-recycle plastic residues, promoting synergistic approached between industrial sectors. Industrial trials at the Feralpi Lonato site confirmed the feasibility of SRA use in EAF without adverse effects on process performance, EAF stability, slag quality, or pollutant emissions. Notable reductions in VOCs (−41%), dioxins and furans emissions (−56%) are observed. The injection system is based on new development made by Tenova, specifically designed to promote iron oxide reduction and slag foaming processes with low-density materials. LCA studies support the use of SRA like BLUAIR® as an alternative to coal in steel making processes, with a 16% reduction in the total (direct and indirect) CO 2 emissions (kg equivalent). A geographical analysis indicates that the creation of an SRA value chain is feasible in various European countries, promoting the development of a new supply chain where steel manufacturer and plastic recycling centers are present on the same territory.

Source: Thermal Science and Engineering Progress

DOI: 10.1016/j.tsep.2025.103497