陈润甲 田艳梅 张钧 陈星 曹素珍

摘    要：为评估焦化厂表层土壤重金属污染的风险，以山西省某焦化厂为研究对象，分析了厂区周围13个点位土壤样品中7 种重金属元素（Cd、Zn、Pb、Cu、As、Cr、Ni）含量。依据有关标准，利用单因子污染指数法、内梅罗综合污染指数法和潜在生态风险评价指数法对土壤污染程度进行了评价。结果表明：研究区域土壤中各重金属含量均超出山西省土壤背景值，超标率为100%，研究区域表层土壤中存在重金属复合污染问题，且As、Cd和Cu污染比较严重。利用单因子污染指数、内梅罗综合污染指数进行风险分析，结果表明7种重金属危害程度大小为As>Cu>Cd>Pb>Cr>Zn>Ni。13个采样点位中As为主要污染因子，As的单因子污染指数平均值为5.66，土壤污染程度为中重度污染，具有较高的风险性;潜在生态风险评价结果同样显示重金属Cd和As具有较强的潜在生态风险。该焦化厂应着重关注As、Cr和Cu三种重金属的后续修复问题，进一步采取措施以减少重金属污染带来的危害。

关键词：焦化厂;土壤;重金属污染;风险评价

中图分类号：X825          文献标识码：A         DOI 编码：10.3969/j.issn.1006-6500.2020.06.019

Abstract： To evaluate the risk of heavy metals pollution in the surface soil of a coking plant in Shanxi Province， the contents of 7 heavy metal elements （Cd， Zn， Pb， Cu， As， Cr， Ni） in 13 soil samples around the plant were analyzed. According to the relevant standards， three different risk assessment methods， including single factor pollution index， Nemerow comprehensive pollution index and potential ecological risk index were used to investigate the pollution characteristics.  The results showed that the content of heavy metals in the soil of the study area exceeded the background value of the soil in Shanxi Province， and the rate of exceeding the standard was 100%. There was the problem of compound pollution of heavy metals in the surface soil of the study area， and the pollution of As， Cd and Cu was serious. The single-factor pollution index and Nemero comprehensive pollution index were used for risk analysis， the results showed that the damage degree of seven heavy metals was As>Cu>Cd>Pb>Cr>Zn>Ni. Among the 13 sampling points， As is the main pollution factor， and the average value of single factor pollution index was 5.66. The degree of soil pollution was moderate to severe pollution， which had high risk. Meanwhile， the result of potential ecological risk index demonstrated that Cd and As had strong potential ecological risk. The coking plant should pay more attention to the follow-up remediation of As， Cr and Cu， and take further measures to reduce the harm of heavy metal pollution.

Key words： coking plant; soil; heavy metal pollution; risk assessment

近年来，随着我国工业的快速发展，一系列环境污染问题层出不穷，其中，重金属污染事件发生的概率极高。土壤是人类健康和谐繁衍的重要环境，土壤质量的好坏直接关系到各种以土壤为生长基质的农产品质量安全和人类的生命健康[1-2]。然而，我国土壤状况令人堪忧，工矿业废弃地问题突出[3]，开展典型遗留场地土壤调查，了解典型企业周边土壤污染程度与特征，对土壤污染防治具有重要意义。我国是世界上第一大焦炭生……