To decarbonize steel production, many European steelmakers are actively transitioning towards the Direct Reduction – Electric Arc Furnace (DR-EAF) route. Therefore, the purpose of this paper was to conduct a Life Cycle Assessment (LCA) on the DR-EAF route across multiple impact categories. The relative significance of impact categories and trade-offs to Blast Furnace – Basic Oxygen Furnace (BF-BOF) steelmaking were identified. Finally, the influence of different burden compositions on the LCA results was analyzed. This paper conducted a literature review on the state of environmental assessments of DR-EAF steelmaking, in addition to developing a Life Cycle Assessment (LCA) for a theoretical site operated in Germany. The LCA was conducted using CML 2001 v. 2016 and the software LCA for Experts. An inventory has been developed for the direct reduction plant, EAF, and continuous casting. Background data was modelled using the Sphera database. A flexible input/output model was developed to represent the EAF, with which three scenarios were investigated, considering different furnace charges. The literature review found that, while many environmental assessments have been conducted on this steel production route, most studies focus on Global Warming Potential (GWP100). Few authors assess multiple impact categories or the relative significance of different environmental impacts for the assessed product systems. The LCA identified environmental hotspots in the production of ore based metallics, electricity, and the defined alloy mix. Through normalization, Abiotic Depletion Potential for Fossil fuels (ADP-F), Acidification Potential (AP), GWP100 and Photochemical Ozone Creation Potential (POCP) have been identified as relevant environmental impact categories for both DR-EAF as well as BF-BOF steelmaking. Compared to the BF-BOF route, a singular trade-off is observed for DR-EAF based steel production for ADP-F. This trade-off can be negated should renewable electricity be used during production. Overall, the DR-EAF route has the potential to lead to improvements in environmental performance across all of the relevant impact categories, when renewable electricity is utilized. It is recommended that future research focus on a more in depth comparison of the DR-EAF and BF-BOF routes, in addition to addressing comparability issues brought on by the assessment of steel scrap using the cut-off method.
Krekel et al. (Thu,) studied this question.