Abstract:Advantages and disadvantages to recover elemental sulfur from zinc pressure acid leaching residue by flotation method, melting and filtration method, ammonium sulfide method is contrastively analyzed. Effects of different factors on leaching process of flotation sulfur concentrate and sulfide filter cake with ammonium sulfide, and on thermal decomposition process of polysulfide solution were analyzed. The results indicate that ratio of liquid to solid and concentration of ammonium sulfide have significant impact on sulfur leaching rate. Sulfur leaching rate from sulfide filter cake is about 95% under optimal conditions. Sulfur leaching rate and recovery from flotation sulfur concentrate is 98%. Purity of sulfur obtained by thermal decomposition of ammonium polysulfide solution is 99.57%. Content of valuable metals in residue after sulfur extraction is enriched by remarkable times, which is favorable for comprehensive utilization of zinc pressure acid leaching residue.