Electrokinetic Remediation of Saline Soil Using Pulse Power

Abstract

Abstract

Pilot-scale electrokinetic (EK) separation field tests (2.2 m×10 m×0.2 m, W×L×D) were performed in a greenhouse to investigate the effects of pulse power on salt removal from saline soil. Initially, greenhouse soil had high electrical conductivity (EC; about 6–21 dS/m), and contained mainly Ca²⁺, Cl⁻, SO₄²⁻, and Na⁺ ions. After 1 month of treatment, the soil EC was reduced 56% using EK direct current (DC), whereas EK pulses (200 kHz) showed a similar (55%) or enhanced EC reduction (72%). Ca²⁺ removal was higher using EK pulses, because the pulses were effective at increasing soil–solution interactions, which dissolved additional Ca²⁺ ions. In addition, EK pulses consumed less than half the electric power of EK DC (134–144 kW·h/m³ vs. 268–354 kW·h/m³) during the same period. Therefore, pulse power both enhances salt removal and saves energy in EK soil remediation.