RECOVERY OF METALS FROM STEELMAKING DUST BY SELECTIVE CHLORINATION - EVAPORATION PROCESS

摘要

Treatment of electric arc furnace (EAF) dusts has become an important issue from the viewpoint of the environmental protection and recycling of variable resources because these dusts contain considerable amount of zinc and lead. A new recovery process of these metals has been proposed, in which the metals in the dusts react with waste polyvinyl chloride to form metal chlorides. Therefore, it is important to clarify the physicochemical properties and behaviors of zinc, lead and those chlorides and oxychlorides. In the present study, the kinetics of chlorination of ZnO, PbO and ZnFe_2O_4 mainly contained in the EAF dusts were investigated at 1023 K to 1273 K with Ar-O_2-Cl_2 gas. Based on these results, the selective chlorination and evaporation process of zinc and lead from the mixture of Fe_2O_3-ZnFe_2O_4-ZnO-PbO was examined and the high efficiency of selectivity has been demonstrated.