Recycled smelter slag as an engineering material - opportunity and sustainability

Abstract. Slags obtained from the Vale Copper Cliff smelter in Sudbury, Ontario, Canada, were investigated as sustainable engineering materials in this study. The recycled smelter waste products can remove toxic contaminants from the aqueous environment as well as be used in the construction industry (as aggregates, cement admixtures, filling materials), soil improvement for agricultural purposes, and other value-added applications and products. The removal mechanisms of the heavy metals (such as Zn, Pb, and Cu, etc.) from aqueous solutions could be physical or chemical adsorption, ion exchange, oxidation-reduction, etc. At the same time, using recycled smelter slags in various engineering applications can help with waste reduction, disposal cost reduction, resource recovery, and increased reused activities. The present study helps explore the scope of using recycled materials in the treatment or construction industry. Using industrial smelter slag as a recycling or renewable resource rather than a waste product has environmental and economic benefits. The study also specifically discusses Ni smelter slag's composition, application, treatment efficiency, opportunity, economic benefits, and circularity for sustainable management.