摘要
本文从理论分析和实验研究两方面综合比较了EKG(Electrokinetic Geosynthetics)电极和铁电极对重金属污染土壤的电渗处理效果。采用电学参数评价加固效果,结果显示温度和电导率之间以及温度与土壤和孔隙水电导率之间具有一定的线性关系。铁电极试验组阴极的平均阴极接触电阻比EKG电极试验组的小60%,而EKG试验组的平均阳极接触电阻比铁电极试验组的小56%。EKG电极试验组和铁电极试验组单位质量污染物的能耗分别为1.895 kJ/g和1.989 kJ/g。电渗后土壤孔隙数量增加,但平均面积减少,平均面积为0.9100~1.0504μm~2。通过微观结构分析,获得了较高的电渗效率,实现了宏观和微观参数间的有效分析和利用。
This study presents a comprehensive comparison of the electro-osmosis treatments of heavy metal contaminated soil using electrokinetic geosynthetics(EKG) and iron electrodes in terms of both theoretical analysis and experimental research. The variation in the electrical parameters was analyzed, and the results show linear relationships between temperature and conductivity and between the soil and pore water conductivities. The average cathode contact resistance of iron is 60% smaller than that of EKG, whereas the average anode contact resistance of EKG is 56% smaller than that of iron. The values of the power consumption per unit mass of contaminants for EKG and iron are 1.895 and 1.989 kJ/g, respectively. After electro-osmosis, the number of soil pores increased, but the average area decreased, with an average area of 0.9100–1.0504 μm~2. Based on microstructure analysis, we obtained higher electroosmotic efficiency and realized the effective analysis and utilization between macroscopic and microscopic parameters.
引文
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