Sequential electrokinetic and landfarming treatment remove hydrocarbon from soil.
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Electrokinetic treatment transports hydrocarbon pollutant to the near cathode side.
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Surfactant flushing can enhance the microbial activity of landfarming.
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Electrokinetic treatment enhances hydrocarbon bioavailability in contaminated soil.
Abstract
A sequential process of electrokinetic soil flushing (EKSF) and landfarming treatment was demonstrated to remove hydrocarbons from clay soil. Surfactant concentration was the independent variable with a concentration of 2×, 4×, 6×, and 8× of critical micelle concentration (CMC), respectively. Environmental changes, the number of microorganisms, and total petroleum hydrocarbon (TPH) concentration were also calculated and measured as response variables. The highest removal efficiency for TPH concentration in electrokinetic remediation occurred when surfactant concentration was 6× CMC while the concentration of TPH was reduced by about 49.9% from the initial concentration. The removal efficiency of the 6× CMC reactor in the landfarming treatment was found to be around 71.1%, and the number of microorganisms increased from 106 to 107 Colony Forming Unit (CFU)/g soil. The sequential process of EKSF – landfarming treatment produces higher removal efficiency than the natural attenuation after 50 days of treatment.
