尾砂柱连续萃取法去除铅锌选矿尾砂中重金属

Removal of heavy metals from lead-zinc tailings in tailings columns by applying continuous extraction

采用0.05mo.lL-1的乙二胺四乙酸(EDTA)作为萃取剂,对铅锌选矿尾砂在尾砂柱中进行了连续萃取实验.实验结果表明,Pb、Zn和Cd等3种金属的萃取效率随萃取时间的增加而增加,萃取60h后,Pb、Zn和Cd的萃取效率分别达到34.35%、53.87%、56.14%.萃取过程中,尾砂柱中不同深度尾砂的重金属含量存在较大的差异,总体呈现中间高、两端低的现象.

In this study,0.05 mol·L^-1 EDTA was used as extractant to leach Pb、Zn and Cd from lead-zinc tailing in tailings columns under certain extraction conditions. The results indicated that the removal efficiency of Pb、Zn and Cd were increased as the extraction time increased. After extraction for 60 hours,the removal efficiency of Pb、Zn and Cd reached 34.35%,53.87% and 56.14%,respectively. During the extraction process,there were significant differences among the heavy metal contents of tailings at different depths in the tailings column; the heavy metal contents of upper and bottom tailings were lower than that of the middle tailings in the tailings column.