空气扰动技术修复氯苯污染地下水的影响因素研究

通过实验室一维砂柱模拟研究了不同影响因素下空气扰动技术(air sparging,AS)修复氯苯污染地下水的效果,包括介质渗透性、曝气方式、共存污染物、残余饱和态氯苯。结果表明:介质渗透性极大地影响着AS的效果,渗透系数越大,去除效果越好。对渗透系数为10-5m/s数量级及其以下的介质应用AS较为困难;在曝气时间相同的情况下,对于渗透系数为5.1×10-4m/s的中砂,脉冲曝气较连续曝气效果好,对于渗透系数为6.2×10-3m/s的粗砂,2种曝气方式效果相仿;苯和氯苯共存时各污染物的去除存在协同作用;AS对残余饱和态氯苯的去除存在着明显的拖尾效应。

A study of the influencing factors of air sparing remediation to chlorobenzene in groundwater

A one-dimensional column was installed to study chlorobenzene removal effect on groundwater with different influencing factors, including medium permeability, air injection mode, coexisting contaminant and residual saturated chlorobenzene. The results show that medium permeability greatly affects AS remediation efficiency. The bigger the hydraulic conductivity is, the better the removal efficiency is. It is difficult to use AS in medium with hydraulic conductivity of less than 10~(-5) m/s. In the same operating time, pulsed air injection has advantages over continuous air injection for medium sand with hydraulic conductivity of 5.1 ×10~(-4) m/s, while the effects of two air injection modes are similar for coarse sand with hydraulic conductivity of 6.2 ×10~(-3) m/s. There is synergistic effect of co-contaminant benzene and chlorobenzene on the removal efficiency. There is a clear tailing effect when AS remediates residual saturated chlorobenzene.