电动土工塑料排水板修复重金属污染高岭土试验研究

Experimental Study on Remediation of Heavy Metal ContaminatedKaolin by Electrokinetic Geosynthetics Drainage Board

针对重金属锌和镉污染的低渗透性高岭土,采用电动土工塑料排水板(EKG)作为电极材料,通过自制模型试验装置研究了电动修复中电势梯度、通电时间、含水率对重金属去除率的影响,确定电动修复的最优试验条件。在最优试验条件下,开展了电极材料、电势梯度对不同种类重金属去除效果影响的试验研究。结果表明:随着修复时间的增长,阳极处重金属污染物逐渐减少,阴极处重金属污染物富集逐渐增加;试验条件相同情况下,重金属污染物Cd的除去率明显高于Zn;电势梯度越大,重金属Zn离子的去除率越高;电动土工塑料排水板作为电极的电动修复重金属污染土的效果要优于石墨电极。研究有助于揭示电动修复重金属污染土的效果和机理,为电动生态环境修复技术的应用提供技术支持。

To remediate low-permeability kaolin contaminated with heavy metals like zinc and cadmium,we developed a model test apparatus with electrokinetic geosynthetics(EKG)drainage plate as the electrode material.The study aimed to investigate the impact of potential gradient,electrification time,and moisture content on the removal rate of heavy metals during electric remediation,and on this basis,to determine the optimal experimental conditions.Under the optimal conditions,we conducted experimental studies to examine the effects of electrode materials and potential gradients on the removal efficiency of various heavy metals.Findings revealed that with increasing remediation time,heavy metal pollutants at the anode gradually decreased,while their concentration at the cathode gradually increased.Under the same experimental conditions,the removal rate of cadmium(Cd)was significantly higher than that of zinc(Zn).Moreover,a higher potential gradient resulted in a greater removal rate of Zn ions.Notably,using EKG as electrodes exhibited a more effective remediation effect on heavy metal-contaminated soil compared to graphite electrodes.This research contributes to the understanding of the effects and mechanisms of EKG remediation on heavy metal-contaminated soil,and provides important technical support for the application of EKG remediation technology.