某厂电镀车间场地土壤与地下水污染特征

Contamination Characteristics of Soil and Groundwater in Electroplating Plant

选择某厂电镀车间作为研究区域,采集土壤、地下水、底泥和地表水样品,对样品的pH值、铬、锌、砷、镉、铜、镍、铅和氰化物含量进行了测试,分析了污染物在该区域内的分布特征。结果表明,研究区域土壤主要受到铬、锌、氰化物污染,43%采样点土壤中锌浓度超出土壤环境质量标准三级标准,29%采样点土壤中总铬浓度超出三级标准。55%的采样点地下水受到锌和六价铬污染。电镀车间污水排放口处土壤和地下水样品中均检测到一定浓度的氰化物。电镀车间架空区域下池塘1底泥和附近池塘3底泥及地表水已经受到铬和锌污染。区域内污水池和污泥池铬、锌浓度则严重超标。元素污染物锌、铬和氰化物分别来源于电镀液、电镀后铬酸盐钝化处理及前期采用的氰化物电镀工艺。在分析目前重金属元素污染场地修复技术基础上,建议研究区域采用植物修复技术进行治理。

Selecting an electroplating workshop of a plant as study area,this research characterised the distribution of contaminants according to collecting soil,groundwater,sediments and surface water samples to determine pH and concentration of chromium,zinc,arsenic,cadmium,cooper,nickel,lead and cyanide.The results showed that some soil in the study area was contaminated by chromium,zinc and cyanide.The concentration of zinc in about 43% sampling points and total chromium in about 29% sampling points exceeded grade Ⅲ of soil environmental quality standard.The groundwater at 55% sampling points was contaminated by zinc and hexavalent chromium.Cyanide was detected both in the soil and groundwater sample at sewage outlet.The sediments and surface water in pond 1 and pond 3 under the electroplating workshop were contaminated.The concentrations of zinc and chromium in sewage tank and sludge pool were much higher than the standard.Zinc,chromium and cyanide analyzed came from plating bath,chromatizing after electroplating and previous cyanide electroplating technology separately.The study recommended that studying area should use phytoremediation on the basis of summarization about previous heavy metal contaminated site remediation technology.