Disposal of zinc extraction residues via iron ore sintering process: an innovative resource utilization

Zinc extraction residue, a solid waste generated from the treatment of zinc-containing dust in rotary kilns, is commonly stockpiled in steel companies for extended periods. It poses significant disposal challenges and environmental pollution risks. So far, research on the treatment of zinc extraction residues has been slow, inadequate, and sporadic. For this gap, a novel approach was proposed to effectively treat the zinc extraction residue via the iron ore sintering process. It was feasible to add 1 wt.% of zinc extraction residues to the sintering raw materials. The more adequate mineralization reaction resulted in higher yield and tumbler indexes, despite a slight decrease in sintering speed. Although this may result in a slight decrease in sintering speed, the more complete mineralization reaction leads to improved sintering yield and tumbler index. Interestingly, the addition of zinc extraction residues reduced the CO and NO x concentrations in the sintering flue gas. Thus, the iron ore sintering process provided a viable solution for resource utilization and environmentally friendly treatment of zinc extraction residues.