贵州某浮选金(砷)精矿预氧化无氰浸出试验研究

Pre-oxidation and Cyanide-free Leaching of Flotation Arsenic-bearing Gold Concentrate From Guizhou Province

贵州某浮选金(砷)精矿中的金主要以微细浸染型赋存在毒砂中,被毒砂包裹,属于高砷高硫金精矿。研究了采用化学预氧化无氰浸出工艺浸出金。结果表明:精矿质量150g,磨细至-38μm,加30g石灰+50g POS-2,控制液固体积质量比3∶1,在55℃、搅拌速度1 992r/min条件下超声预处理2h,反应50h,渣中金质量分数降至2.01g/t,金浸出率达92.12%,砷质量分数降至1.86%,砷浸出率为81.21%,预氧化同时实现了金的无氰同步浸出。该方法对同类型原生金矿石的预氧化浸出有借鉴意义。

The glod in flotation arsenic-bearing gold concentrate from Guizhou province exists in arsenopyrite as fine-disseminated type and is difficult to be leached using cyanide.Leaching of gold and arsenic from the gold concentrate by chemical pre-oxidation process was studied.The results indicate that for the 150 g gold concentrate of grinding fineness to-38 μm,under the conditions of pre-oxidation dosage of 30 g Lime＋50 g POS-2,liquid-to-solid ratio of 3/1,ultrasonic treatment time of 2 hours,temperature of 55 ℃,reaction time of 50 hours,stirring speed of 1 992 r/min,the leaching of gold and arsenic are 92.12% and 81.21%,respectively.The content of gold and arsenic in the leaching slag are decreased to 2.01 g/t and 1.86%,respectively.The gold is simultaneous leached without cyanide.The process can be referenced in the pre-oxidation leaching of the same type of gold ore.