傍河污染场地地下水修复技术筛选

Screening groundwater remediation technology for riverbank pollution sites

针对目前地下水修复技术方法众多,有着不同适用性和优缺点的情况,对不同的污染场地类型国内外尚未形成一套成熟的筛选机制.本文引入IOC(importance order of the criteria)筛选法,以地下水修复技术的修复成本、修复时长、技术有效性、技术可靠性、工人保护及人群保护为筛选指标,以吉林市某废弃工厂为研究区,在结合地下水污染调查和地下水人体健康风险评价的基础上确定了场地地下水的修复目标污染物,根据场地区域水文地质条件分析和目标污染物特性,结合抽出处理、曝气技术、渗透反应墙等地下水污染修复技术特点,筛选出合理的地下水污染修复方案.结果显示,场地地下水中苯并(a)芘的致癌风险超过单项污染物的可接受致癌风险限值,确定为修复目标污染物.经过IOC排序法分析确定,在有效性优先条件下,抽出-生物反应器法是理想的修复技术;在经济优先的条件下,地下水曝气技术适用于该场地的修复技术;综合有效性和经济优先2种条件,组合技术抽出-生物反应器法结合地下水曝气技术适宜于该场地的修复技术.

Emerging technologies for remediation of groundwater contamination generally have varied applicability, advantages and disadvantages, but contaminated sites at home and abroad have not yet formed any mature selecting system. How to select individual or combined technology for different types of contaminated sites is of vital importance. A ferroalloy abandoned factory in Jilin was studied. Groundwater pollution was investigated, health risk was assessed, pollutants in groundwater were determined. Hydrogeological conditions and characteristics of target pollutants were analyzed. Groundwater pollution remediation techniques PB （pump and bioreactor）, AS （air sparging） and PRB （permeable reactive barrier） were assessed, to obtain a reasonable groundwater remediation scheme by importance order of the criteria （IOC）. IOC consisted of six criteria： cost, time, effectiveness, public health and efficiency. The carcinogenic risk of benzo（a）pyrene in the groundwater was found to have exceeded the acceptable carcinogenic risk limit of the single pollutant, which was used as the target pollutant. Under condition of efficiency priority, the PB method was found to be the ideal de-contamination technology. Under condition of economic priority, the AS technology was found to be the ideal de-contamination technology. Under comprehensive efficiency priority and economic priority, PB and AS technology were found to be the ideal de-contamination technology for the site.