Comparative experiments on electro-osmotic treatment effect of polluted soil using EKG and iron electrodes

Abstract

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 μm². Based on microstructure analysis, we obtained higher electroosmotic efficiency and realized the effective analysis and utilization between macroscopic and microscopic parameters.

Keywords

EKG / contaminated soil / electrical conductivity / ion transport / microstructure

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