电动与渗透反应格栅联合修复镉污染地下水实验

通过实验方法研究了地下水中镉污染的电动力学修复效果，并分析其迁移变化特征。实验结果表明，电动修复中由于阴阳两极的氧化还原反应造成电极附近pH值产生明显变化，其中阳极附近的pH值由开始时的7.0逐渐变小到6.8，而阴极附近则相反，由开始时6.9逐渐增大到9.1，表明土壤的酸碱条件变化明显。Cd浓度变化反映在自然渗透条件下含水层中重金属污染物的迁移能力较弱，阳极附近地下水中Cd的去除率仅8.4%，而在电场作用下地下水中重金属的浓度发生明显变化，使得重金属污染物能在电极附近富集而被去除，当实验电场强度为0.5 V/cm时，Cd在阴极的累积使得阳极附近地下水中去除率为72.9%，说明电动修复重金属Cd污染地下水的效果明显好于自然渗透状态。

Experiment on combined electrokinetic remediation with PRB of cadmium contaminated groundwater

The efficiency of electrokinetic remediation of cadmium contaminated groundwater was researched by means of experiments in this paper, and the migration and variation characteristics of cadmium was analyzed too. The experimental results indicated that the pH value varied obviously during the electrokinetic remediation because of the oxidation and reduction near the electrodes, and the pH value near the positive electrode changed from 7.0 in initial stage to 6.8 at later stage, and the pH value was on the contrary near the negative electrode, namely, changed from 6.9 in the beginning to 9.1 in the last, which made known that the condition of acidity and alkalinity in soil varied clearly. The variation of cadmium concentration made known that the migration of heavy metal was weak in the aquifer and the removal efficiency of cadmium near the positive electrode was only 8.4% in the condition of natural permeation, but the concentration of heavy metal varied obviously in groundwater under the electric field, and the heavy metal pollutant could be enriched and removed in the vicinity of electrode. The removal efficiency of cadmium in the groundwater near the positive electrode was 72.9% when the experimental intensity of electric field was 0.5 V/cm, which indicated that the effect of electrokinetic remediation of cadmium contaminated groundwater was evidently higher than that in the condition of natural permeation.