高砷废渣中砷的稳定化

Stabilization of As in High Arsenic Waste Slag

以湖南某铅锌冶炼企业高砷废渣为研究对象,考察了不同铁盐对废渣中砷的稳定化效果,选取了最佳铁基稳定剂,进一步研究了氧化钙和高锰酸钾对砷的强化稳定化作用,对不同稳定化药剂用量进行了优化,并揭示砷的稳定化机制。结果表明:七水硫酸亚铁对废渣中砷的稳定化效果最佳,且氧化钙和高锰酸钾对七水硫酸亚铁稳定化砷具有显著的强化作用。在高锰酸钾用量2%、七水硫酸亚铁用量为3%、氧化钙用量1%的条件下,废渣中砷稳定化率达到86.07%,浸出液pH值为8.89,砷的稳定化机理包括氧化、表面络合和化学沉淀作用。

High arsenic waste slag obtained from a lead-zinc smelting enterprise in Hunan province was taken as the research object.The stabilization effect of different iron salts on arsenic in the waste slag was investigated to choose the best iron-based stabilizer,and the enhanced stabilization effect of calcium oxide and potassium permanganate on arsenic was further studied.The dosage of different stabilizers was optimized and the stabilization mechanism of arsenic was revealed.The results showed that ferrous sulfate exhibited the best stabilization performance on arsenic in the waste slag,and calcium oxide and potassium permanganate had a significant strengthening effect on the stabilization of arsenic by ferrous sulfate.Under the conditions of 2%potassium permanganate,3%ferrous sulfate and 1%calcium oxide,the stabilization efficiency of arsenic in the waste slag reached 86.07%,and the pH value of leaching solution was 8.89.The stabilization mechanisms of arsenic included oxidation,surface complexation and chemical precipitation.