Novel Fusion Electrokinetic Technology with Gas Re-Injection (GREK) for Soil Remediation and Stabilization

In this study, a gas reinjection type electrokinetic remediation treatment process (GREK) was proposed as the method for the restoration and stabilization of contaminated soil. The proposed electrokinetic remediation was a new technique, where treatment was performed by reinjecting the surplus gas, which was produced from an anode chamber, into soil, in order to remove the heavy metals and moisture that exist in clayey soil or clayey-sandy soil with low hydraulic conductivity. The manufactured samples were completed through the compression process, in which pressure was gradually increased to a final pressure of 2.11 kgf/cm2 (30 psi) during a total of 7 days. Before the compression, the samples were taken, and the heavy metal concentration and water content were measured. For the gas reinjection type electrokinetic remediation treatment process (GREK) and non-injection type treatment method, continuous treatment processes were performed for 24 hours at a voltage gradient of 2 V/cm. The results of the water content indicated that the gas reinjection type electrokinetic remediation treatment process (GREK) was about 3% higher than that for non-injection type treatment method. The removal efficiency of chromium (Cr)indicated that the gas reinjection type electrokinetic remediation treatment process (GREK) was about 15% higher than that for non-injection type treatment method. The removal efficiency of cadmium (Cd) indicated that the gas reinjection type electrokinetic remediation treatment process (GREK) was about 22% higher than that for non-injection type treatment method. It is expected that the proposed gas reinjection type treatment method would contribute to convergence electrokinetic treatment processes in the future.