Treatment of Oil-Contaminated Soil from Kuwaiti Dry Oil Lakes: Development of a New Processing Technology

Abstract

Oil-contaminated soil of a dry oil lake which was taken from Kuwait included two types of samples, namely, oil sludge and oil soil. Through the analysis of physical and chemical properties, the results show that both of them with high oil content had a certain recycling value combined with a poor dispersion effect in water. Then, a new process based on countercurrent extraction was designed to treat the oil-contaminated soil. Through a series of laboratory-scale experiments, the optimal processing conditions were found, in which the oil content of tails was lower than 0.5% and the oil obtained from the organic phase by evaporating could be reused. Furthermore, the reaction conformed to the kinetic characteristics of the quasi-first-order reaction; the activation energy (E a) was 27.425 kJ/mol (oil sludge) and 51.839 kJ/mol (oil soil), and the extraction mechanism of the compound extractant was expounded. The proposed countercurrent extraction method shows well performance to recover oil from oil-contaminated soil which is economically efficient and supports environmental protection.