某石墨阳极法氯碱生产场地二噁英污染特征分析

Analysis of Characteristics of Dioxin Contamination in the Chlor-alkali Site that Uses Graphite Anode for Production

为了解石墨阳极法氯碱生产场地二噁英类物质污染场地环境特征,对某氯碱生产场址进行了土壤和地下水采样及检测分析.结果表明,土壤样品中二噁英毒性当量值超过美国EPA区域筛选值(RSL)的超标点主要集中在场地内氯氢气处理车间、电解槽车间、石棉堆放区、污水处理厂和油库区,毒性当量在1.482～1 357.459 ng.kg-1之间;地下水样品二噁英浓度限值未超过我国饮用水标准值.结合场地二噁英污染浓度指纹特征以及二噁英异构体含量及其毒性当量因子,该场地内优先控制的污染物为2,3,7,8-TCDF、2,3,4,7,8-PeCDF、1,2,3,4,7,8-HxCDF、OCDD和2,3,7,8-TCDD.研究结果表明,采用石墨阳极法生产氯碱行业的场地二噁英类物质污染程度比较严重,需要开展针对该类型场地的环境监管工作.

In order to find out the characteristics of dioxin contamination,we sampled and analyzed the soil and groundwater on a chlor-alkali factory site that uses graphite anode for production.The results show that the toxic equivalent quantity(TEQ) of dioxins in soil samples exceeds the U.S.EPA region screening value(RSL),with the chlorine hydrogen processing workshop,the electric tank workshop,the asbestos stack area,the sewage treatment plant and the oil depot were affected.The dioxin concentration limit of the groundwater sample doesn't exceed the drinking water standard of China.Considering the fingerprints characteristics of dioxin-contaminated concentration,dioxin isomers content and TEQ,the priority pollutants for control on this site are 2,3,7,8-TCDF,2,3,4,7,8-PeCDF,1,2,3,4,7,8-HxCDF,OCDD and 2,3,7,8-TCDD.The results show that dioxin pollution is very serious in the chlor-alkali plant that uses graphite anode for production,and the environmental supervision is imperative.