Enhanced Electrokinetic Remediation of Copper-Contaminated Soil by Combining Steel Slag and a Permeable Reactive Barrier

Electrokinetic (EK) remediation methods can remove heavy metals from the soil, but the removal efficiency is generally low. In this paper, indoor remediation experiments of simulated copper-contaminated clay under four different types of electrolyte conditions (KCl, HAc, AC, and PASP (polyaspartic acid)) are carried out to validate the theory of an electrodynamically coupled steel slag permeability reactive wall (PRB). By comparison with EK remediation, it has been shown that the EK-PRB coupled remediation method can promote the removal of heavy metal copper in the soil, especially in the removal of reducible copper and exchangeable copper. The method can effectively avoid the increase in soil pH value and reduce the accumulation range of heavy metals while reducing the accumulation amount of heavy metals. This method has better energy utilization efficiency, and the unit energy consumption is smaller than the single electric remediation test.