重庆市工业园区污泥重金属含量分析及生态风险评价

Analysis of Heavy Metal Content and Ecological Risk Evaluation of Sludge from Industrial Parks in Chongqing,China

本文采集重庆市工业园区89家集中式污水处理厂污泥,对8种主要重金属含量进行分析,并与城镇污泥以及其他地区工业污泥重金属含量进行比较,评价其生态风险,分析重金属含量较高的园区污泥重金属来源。结果表明:各重金属元素(Hg、As、Cd、Pb、Cr、Ni、Cu、Zn)的含量变化范围分别为0.02~18.55、0.04~59.80、1.5~21.85、25~364、2.5~57950、3.65~94509、1.39~18501、10.95~83750 mg/kg。重庆市工业园区污泥中Hg、As、Cd和Pb的含量低于城镇污泥和其他地区工业污泥,Cr、Ni、Cu、Zn的含量在高百分位值时显著高于城镇污泥中的相应值。生态风险评价结果显示Hg、Zn、Ni、Cu、Cr、Cd在部分污水处理厂中存在不同程度的风险。机械设备制造业、电子设备制造业和金属制品业等行业污泥中重金属含量较高。

Sludge from 89 centralised wastewater treatment plants in industrial parks in Chongqing was collected.The contents of eight major heavy metals were analysed and compared with the heavy metal contents of municipal sludge as well as industrial sludge from other areas to analyse the ecological risks and to understand the sources of heavy metals in sewage treatment plants with high heavy metal contents.The results showed that the content of each heavy metal element(Hg,As,Cd,Pb,Cr,Ni,Cu,Zn)varied in the ranges of 0.02~18.55,0.04~59.80,1.5~21.85,25~364,2.5~57950,3.65~94509,1.39~18501,10.95~83750 mg∕kg.The contents of Hg,As,Cd and Pb in the sludge from industrial parks in Chongqing were lower than those in urban sludge and industrial sludge from other areas,and the contents of Cr,Ni,Cu and Zn in the sludge from industrial parks were significantly higher than the corresponding values in urban sludge at high percentile values.The results of the ecological risk evaluation showed that Hg,Ni,Cu,Zn,Cr,Cd existed in different degrees in some wastewater treatment plants.The heavy metal content in sludge from industries such as mechanical equipment manufacturing,electronic equipment manufacturing and metal products industry was high.