Impact of Crude Oil Contamination and Low-Temperature Thermal Desorption on Soil Properties and Remediation Efficacy

Abstract

Crude oil contamination significantly alters soil properties, posing environmental risks and challenges for sustainable development. This study investigates the potential of low-temperature thermal desorption (LTTD) at 110°C as an environmentally friendly remediation technique for crude oil-contaminated soils. Soil samples contaminated with crude oil from Nigeria’s Niger Delta were analyzed for changes in Atterberg limits, specific gravity, linear shrinkage, sodium percentage (PS), and total dissolved solids (TDS). After LTTD treatment at 110°C for 30 minutes, the soils were assessed using gas chromatography, Fourier transform infrared spectrometry, X-ray diffraction, and scanning electron microscopy to evaluate microstructural and mineralogical changes. Contamination increased plasticity, shrinkage, and dispersivity, while reducing specific gravity. LTTD successfully removed up to 96% of hydrocarbons, but also caused a 15% weight change and minor alterations in hydrocarbon functional groups. Scanning electron microscopy revealed particle agglomeration after remediation, which may help counter the increased dispersivity caused by contamination. X-ray diffraction showed no significant mineralogical changes in the remediated soils. LTTD at 110°C proves effective in reducing hydrocarbons and mitigating crude oil-induced soil degradation, contributing to sustainable environmental management.