某金矿氰化尾矿脱氰试验研究

Experimental research on the decyanidation of cyanide tailings from a gold mine

对某金矿氰化尾矿分别采用碱氯法、过氧化氢氧化法、固液分离法进行脱氰试验研究,3种方法处理后尾渣毒性浸出液中总氰化合物质量浓度均低于5 mg/L,但固液分离法总氰化合物去除率相对较高,且无需使用药剂,采用其进行工业规模验证试验。试验结果表明:该工艺运行稳定,处理后尾渣平均含水率为18.56%,总氰化合物质量分数低于1500 mg/kg,毒性浸出液中总氰化合物质量浓度稳定低于5 mg/L,可降低氰化尾矿再利用处置环境风险,拓宽处置途径。

The decyanation of cyanide tailings from a gold mine was studied through the alkali chlorine method,the hydrogen peroxide oxidation method,and the solid-liquid separation method.After the cyanide tailings are treated by these 3 methods,the mass concentration of the total cyanide compound in the toxic leaching solution is<5 mg/L.In comparison,the solid-liquid separation method had a higher removal rate of total cyanide compounds and did not require the use of chemicals.The method was subsequently used in industrial-scale validation tests.The results showed that the solid-liquid separation process was stable,the average water content of the treated tailings was 18.56%,and the mass fraction of total cyanide compounds was less than 1500 mg/kg,the mass concentration of total cyanide compounds in the toxic leaching solution is steadily<5 mg/L,which can lower the environmental risks to reuse cyanide tailings and extend disposal pathways.