Oil recovery and characterization of bottom tank oily sludge from brega oil refinery in libya by solvent extraction

The aim of this work is to recover and characterize oil from Bottom Tank Oily Sludge from Brega oil refinery in Libya. The benefits would be two-folds, firstly to reduce the environmental impact of oily sludge and secondly to improve oil utilization efficiency as the sludge has a high content of valuable hydrocarbons. Oily sludge and recovered oil were characterized and key parameters were measured including water content, light and heavy hydrocarbon content, solid content ash and salt content, carbon residue, density, specific gravity, API (American Petroleum Institute) gravity, viscosity, SARA analysis and gas chromatography. Four different types of solvent were used to recover oil from solid and semi-solid sludge. The effect of various parameters namely shaking time, Temperature and solvent volume upon oil recovery were investigated. Within the range of the studied operating conditions herein, the maximum oil recovery obtained varied from 82.5 – 86.6% depending upon the amount of oil within the sludge and the solvent efficiency used for extraction. A detailed study of the kinetics of solvent extraction based on oil recovery was carried out