(中南大學冶金與環(huán)境學院，長沙 410083)
摘 要: 提出并研究鹽酸浸出-鐵粉置換-硫化沉淀-噴霧熱解綜合利用窯渣鐵精礦的新工藝。結果表明：當鹽酸濃度為6 mol/L，浸出溫度為60 ℃時，Ag、Pb、Cu、Fe和Zn的浸出率分別達到99.95%、99.34%、95.07%、89.44%和57.92%。所得鹽酸浸出液中加入理論量1.25倍的鐵粉，Cu和Ag的脫除率均可達到98%以上。當硫化亞鐵用量為理論量的3倍時，鐵粉置換后液中Pb、Zn的脫除率可達96%以上，凈化后液中雜質總量低于500 mg/L。以硫化沉淀后的液體為原料進行噴霧熱解，在溫度高于700℃時，可制得平均粒度(D50)為12μm、純度＞99%的類球形Fe2O3粉末。利用這一工藝，不僅可高效回收窯渣鐵精礦中的有價金屬，還可將鐵資源轉化為具有較高附加值的氧化鐵產(chǎn)品，從而實現(xiàn)窯渣鐵精礦的綜合利用。
關鍵字: 濕法煉鋅；窯渣；浸出；噴霧熱解；硫化沉淀
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:A novel process, including hydrochloric acid leaching, iron powder replacing, sulphide precipitation and spray pyrolysis, was proposed to treat iron concentrate recovered from zinc kiln slag for comprehensive utilization. Treated by solution of 6 mol/L hydrochloric acid at 60 ℃, the leaching rates of Ag, Pb, Cu, Fe and Zn reach 99.95%, 99.34%, 95.07%, 89.44% and 57.92%, respectively. More than 98% Cu and Ag are recovered from the leach liquor when stoichiometric ratio of iron powder is 1.25 times of the theoretical value. More than 96% Pb and Zn is removed with three times of theoretical consumption of FeS, and the concentration of impurities of the final solution is less than 500 mg/L. Fe2O3 powder, which is spherical with mean size of 12 um and purity of 99%, is prepared with final solution at above 700 ℃. By this process, not only the metal values can be recovered effectively, but also the iron resources of zinc kiln slag can be converted into Fe2O3 with high purity, thus, the comprehensive utilization of iron concentrate recovered from zinc kiln slag can be realized.
Key words: zinc hydrometallurgy; kiln slag; leaching; spray pyrolysis; sulphide precipitation
