铅锑复杂硫化矿铅锑分离的理论及新工艺研究

There are abundant lead-antimony complex sulfide ore resources in China. The key problem of treating these complex sulfide ores is to separate antimony from lead. In the conventional smelting process, the lead-antimony complex sulfide ore is firstly oxidized into oxide materials in a fluidized-bed furnace. The oxide materials produced is then reduced to lead-antimony alloy in a blast furnace or reverberatory furnace. The lead-antimony formed is oxidized by blowing air in a reverberatory furnace to separate antimony from lead. Antimony as an oxide is recovered in the gas phase, whereas lead is remained in the residue alloys. The conventional process is so complicated that the recoveries of antimony and lead are very low. .In this project an oxidation-volatilization roasting process for jamesonite (Pb4FeSb6S14) concentrate with steam is developed for the direct separation of antimony from lead. The reaction mechanism of Sb2S3, PbS, FeS and ZnS pure sulfides, Sb2S3－PbS binary system,Sb2S3－PbS－FeS and Sb2S3－PbS－ZnS ternary as well as Sb2S3－PbS－FeS－ZnS quarternary systems with steam is investigated with XRD, SEM, EDAX, DTA and TG. It is demonstrated that Pb4FeSb6S14 can be dissociated into simple sulfides (Sb2S3, PbS, and FeS) by steam at elevated temperatures, resulting in a considerable increase in the activity and volatility of antimony trisulfide. When using air instead of steam, however, Pb4FeSb6S14 can be transformed into a complex oxide Pb4FeSb3O13 and the volatility of antimony is appreciably reduced. The volatilization rate of Sb2S3 in steam atmosphere is faster than that in argon atmosphere, whereas the volatility of PbS in steam atmosphere is decreased as compared with that in argon atmosphere. When steam is used to the volatilization roasting process of jamesonite concentrate, therefore, antimony will be preferentially vaporized and condensed in the fume dust, and lead and other associated metals such as Zn, Fe and Ag will be remained in the residue. The antimony-containing dust can be used for the recovery of antimony by a reduction smelting process, and the residue for the recovery of lead and other associated metal values by Imperial Smelting Process (ISP). Under optimum conditions, the direct recoveries of antimony and lead are 92-97% and 92-98, respectively. In comparison with the conventional flowsheet, the advantages of the present Pb-Sb separation method include simpler flowsheet, better Pb-Sb separation result and higher recoveries of metal values. It has good application prospects in industry. The related theoretical research results are of scientific significance for the better understanding of the reaction mechanism of metal sulfides with steam. .

本项目研究直接从铅锑复杂硫化矿分离铅锑的理论及新工艺，用水蒸气将矿石中的三硫化二锑选择性地氧化为氧化物，使其从硫化物固溶体中解离出来，通过挥发而与铅锌等金属分离。本项目对于开发我国丰富的铅锑复杂硫化矿资源、简化传统流程、提高金属综合回收率、丰富有色多金属硫化矿的冶金新理论，具有广阔的工业应用前景和重要的科学意义。