郴州工业场地重金属和PAHs复合污染特征及风险评价

研究了郴州市焦电、煤矿和冶炼等三类工业场地土壤中Cu、Pb、Zn、Cr、Cd、As等重金属和16种PAH的污染状况及评价。结果表明:冶炼类工业场地主要存在Pb、Zn、Cu、As及PAHs污染,超标率均在50%以上,最高超标近百倍。煤矿类场地主要存在As和PAHs污染,其中As超标率为87.5%,最高超标2.4倍;PAHs超标率为75%,最高超标6.7倍。焦电类场地主要为PAHs污染,超标率达81.2%,最高超标34倍。对三类工业场地PAHs进行源解析,发现焦电类工业场地主要为煤燃烧源,而煤矿类主要为石油源,冶炼类场地主要为煤和石油的混合来源。三类工业场地存在不同程度的复合污染,其中As与PAHs复合污染最为普遍,Pb与PAHs在三类工业场地均显著相关。对三类工业场地PAHs和重金属进行污染评价的结果为,冶炼类>焦电类>煤矿类,其中焦电类工业场地以PAHs污染最严重,冶炼类工业场地以重金属污染为主。

Combined pollution of heavy metals and PAHs and its risk assessment in industrial sites of Chenzhou city

This paper investigated the pollution of heavy metals and polycyclic aromatic hydrocarbons(PAHs) in three typical industrial contaminated sites such as coke power plant,coal mining and smelting industry in Chenzhou city,southern China.The results showed that the pollution of Pb,Zn,Cu,As and PAHs in the soil of smelting industrial sites was serious,with more than 50% samples exceeding the limits and the highest concentration exceeding the standards by 100 times.In coal mining sites,it was shown that 87.5% of the samples were above the arsenic limits and 75% of the samples were above the PAHs limits.In coke power plants,81.2% of the samples exceeded the limits and the maximum content of PAHs exceeded the standards by 34 times.It was estimated that the sources for PAHs were different in the three industrial sites.The PAHs of power plants and coal mine sites mainly originated from coal combustion and petroleum,respectively,while the PAHs of smelting plants were mainly from mixed source of coal combustion and petroleum.It was suggested that arsenic and PAHs were widely observed in industrial sites,and some heavy metals such as Pb were significantly correlated with PAHs.The pollution risks of PAHs and heavy metals were estimated in the order of smelting industrial sites >coke power plants > coal mining sites.It was assessed that the pollution risk of PAHs in power plants was the highest,and that the pollution risk of heavy metals in smelting industrial sites was the highest.