Application of superabsorbent geotextiles to decontaminate and improve crude oil-contaminated soil

Abstract

The contamination of soil by various oil products is a severe geo-environmental problem. In this study, some geotextiles were used as superabsorbent geotextiles to decontaminate soil polluted with crude oil. The ability of these geotextiles to absorb oil is better than that of absorbing water. The removal efficiency of the absorbent geotextile was first evaluated by placing the spacer fabrics in different arrangements in contaminated soil samples. Second, the shear strengths of the decontaminated soil samples were evaluated through a series of direct shear tests and compared with those of contaminated soil. The effects of crude oil content, vertical stress, and geotextile arrangement were thoroughly investigated to understand the vivid behavior of the specimen matrix. The results showed that the geometric properties of geotextile and sand, such as the mean size of sand particles, aperture size, fluffs, and piles of geotextile, geotextile roughness, and the two phases occurring in the specimens – wettability and saturation of absorbent layer – are vital in determining the sand-geotextile interface and the behavior of shear strength parameters of the matrix. Ultimately, the results confirmed the efficiency of absorbent geotextile as a potential method for controlling soil contamination and improving the shear strength parameters.