Comprehensive analysis of the environmental impact of electric arc furnace steel slag on asphalt mixtures

Abstract

This paper analyses the environmental impact of replacing high-quality coarse aggregates by electric arc furnace (EAF) steel slag. A Life Cycle Assessment (LCA) was performed on three asphalt mixtures containing different aggregates: namely ophite, slag 1 and slag 2. The inventory gaps were filled by performing several laboratory tests and applying theoretical models. Furthermore, the sensitivity of the results when applying several allocation procedures, aggregate moisture content and ophite transport distances was also analysed. The results showed the great importance of both the aggregate absorption rate and, above all, the humidity. Slags can replace ophite located more than 144 km from the asphalt plant.