柴河铅锌尾矿中重金属铅、锌、镉的迁移特征  

Migration characteristics of the heavy metals lead,zinc and cadmium from Chaihe lead-zinc tailings

作　　者：王媛[1] 魏忠义[1] 张卫[1] 畅琪 

机构地区：[1]沈阳农业大学土地与环境学院,辽宁沈阳110866

出　　处：《环境污染与防治》2015年第10期58-62,69,共6页Environmental Pollution & Control

基　　金：国土资源部公益性行业科研专项经费项目(No.201111016-03)

摘　　要：采用柱状淋滤实验模拟降水,研究柴河铅锌尾矿中重金属铅(Pb)、锌(Zn)、镉(Cd)的迁移特征。结果表明:无覆土层的尾矿柱(柱1)与含50cm覆土层的尾矿柱(柱2)淋滤液pH均在30d分别出现最低值5.86和6.67;在180d分别出现最高值7.85和7.89。柱1淋滤液中Pb、Zn、Cd最高质量浓度分别为0.053 0、5.980 0、0.009 4mg/L,均超过《地表水环境质量标准》(GB 3838—2002)的Ⅳ类标准规定的限值。柱2淋滤液中Pb、Cd最高浓度符合GB 3838—2002的Ⅳ类标准,Zn最高浓度超过GB 3838—2002的Ⅳ类标准规定的限值。随着淋滤时间延长,柱2淋滤液中Pb、Zn、Cd浓度均低于柱1,说明表层覆土措施可减少尾矿中重金属淋失。经过柱状淋滤实验,柱2中40cm处Pb、Zn、Cd全量相比原覆土分别增加17.47%、23.37%、26.09%,表明下部尾矿层中的重金属可向上部覆土层迁移。Leaching column experiment was used to simulate precipitation and investigate the migration characteristics of heavy metals lead （Pb）,zinc （Zn） and cadmium （Cd） in lead-zinc tailings. The results showed that the lowest pH of leachate from tailing column without soil cover （column 1） and tailing column with 50 cm soil cover （column 2） were 5.86 and 6.67 on 30 d, respectively; the highest pH were 7.85 and 7.89 on 180 d,respectively. The highest mass concentrations of Pb,Zn,and Cd in column 1 leachate were 0.053 0,5.980 0 and 0.009 4 mg/L respectively,exceeding level IV standard of ＂Environmental quality standards for surface water＂ （GB 3838-2002）. The highest mass concentrations of Pb and Cd in column 2 conformed to level IV, while Zn exceeded. With extended leaching time,the mass concentrations of Pb, Zn and Cd in column 2 were lower than those in column 1, indicating that the measure of surface soil cover reduced the leaching of heavy metals in the tailings. In layer 40 cm of column 2 ,the total contents of Pb,Zn,and Cd increased 17.47%,23.37% and 26.09% compared with the original soil cover respectively after leaching column experiment,suggesting that heavy metals in the tailings might migrate upward to soil cover.

关 键 词：铅锌尾矿 重金属 覆土 柱状淋滤实验 

分 类 号：X753[环境科学与工程—环境工程]