含金硫精矿焙烧除砷选铁-硫脲法提金试验研究

Experimental Study on Gold Extraction from Gold-bearing Pyrite Concentrate by Roasting for Arsenic Removal and Thiourea Leaching of Gold

对含低品位金的硫精矿进行再选,获得含硫50%左右的再选硫精矿;对再选硫精矿进行二段焙烧除砷脱硫,可以获得含砷0.056%、含铁61%左右的烧渣,且其中金、银得以富集;对烧渣进行了稀硫酸预处理-硫脲浸金试验,浸金试验结果表明,当磨矿粒度为-0.074 mm粒级占60%,矿浆pH=1～2,液固比为1∶2,硫脲用量为10 g/L,硫酸铁用量为3 g/L,浸出时间为6 h时,金的浸出率达90.4%。

A pyrite concentrate containing about 50% sulfur was obtained after the pyrite containing low-grade gold being subjected to reflotation. Then after two-stage roasting for removing arsenic and sulfur, a pyrite slag graded 0. 056% As, 61% Fe was obtained with higher-grade gold and silver. An experiment on such slag being pretreated with dilute sulfuric acid followed by thiourea gold-leaching showed the following results ： at a grind size of - 0. 074 mm 60%, with pH of 1 - 2, liquidsolid ratio of 1：2, leaching time of 6 h, thiourea and ferric sulfate dosage of 10 g/L and 3 g/L, respectively, leaching rate of gold was up to 90.4%.