This work is intended for comparing the valuable hydrocarbons (oil) recovered by solvent extraction method from the wasted oily sludge from Brega and Ras Lanuf oil refineries in Libya. As petroleum sludge has a high percentage of valuable oil, the advantages of this comparative study are: Reducing environmental problems resulting from oily sludge; and not losing a high percentage of oil within the sludge, and thus improving the economic value of the treatment process. The recovered oil and the original sludge were subjected to evaluations based on the following parameters: water content, light and heavy hydrocarbon content, solid content ash and salt content, carbon residue, density, specific gravity, API (American Petroleum Institute) gravity, viscosity and SARA analysis.
In this study, five solvents were applied as carrier to extract oil from the two sludge samples that were investigated in this study. Naphtha (Naph.), Kerosene (Keros.) cuts and mixtures of these two cuts (Naphtha/Kerosene mixing percentages are 1:1, 3:1 and 6:1). The effect of various parameters namely solvent volume, contact (stirring) time and temperature during oil extraction were studied. It was found that, the best solvent used is the mixture of Naphtha/Kerosene (6:1), for the Brega oil refinery, the maximum extracted oil was 94.90 – 97.53% and for Ras Lanuf oil refinery the maximum extracted oil was 93.5 – 95.5 % for solid and semi-solid sludges respectively.
