某硫酸烧渣中有价金属综合回收试验研究

Experimental study on comprehensive recovery of valuable metals from a pyritic slag

某硫酸烧渣直接作为铁精矿外售,其中的金、银、铜、锌没有得到回收,造成有价金属资源的浪费。试验采用三级工艺(一级酸浸脱铜脱锌、二级硫化沉铜沉锌、三级金银环保浸出)进行处理,并对试验条件进行了优化。在最佳条件下,硫酸烧渣中的铜、锌经酸浸—沉淀,综合回收率分别达到70.08%、67.66%;酸浸渣在氢氧化钠中和至pH值为9~10,液固比2∶1,BK516环保提金剂用量0.09%,浸出时间18 h条件下,获得了较好效果,金、银浸出率分别达到54.17%、56.52%,解决了硫酸烧渣中有价金属综合回收利用的技术难题,具有较好的经济效益和环境效益。

A pyritic slag is sold directly as iron concentrates.The gold, silver, copper, and zinc are not recovered, which is a loss of valuable metal resources.The experiment uses a three-stage process(first-stage acid leaching for copper and zinc removal, second-stage copper and zinc precipitation by sulfurization, and third-stage environmentally friendly leaching of gold and silver) for treatment, and optimizes the test conditions.Under optimal conditions, the copper and zinc in pyritic slag, after acid leaching-precipitation, have comprehensive recovery rates of 70.08 % and 67.66 % respectively;good indexes that gold and silver leaching rates are 54.17 % and 56.52 % respectively are obtained when the acid leaching slag is neutralized to pH 9~10 with sodium hydroxide, the liquid-solid ratio is 2 ∶1,the environmentally friendly gold leaching reagent BK516 dosage is 0.09 %,the leaching time is 18 h.The process solves technical challenges to comprehensively recover and utilize valuable metals in pyritic slag and creates good economic and environmental profits.