Abstract:The deoiling treatment of aged oil sludge in one oilfield of northeast of China by solvent extraction with activating agent was studied under commom laboratory conditions. The solvent mainly consisted of aromatic hydrocarbon, and the activating agent mainly consisted of polyoxyethylene ether.The residual oil rate of tailings was 0.23% under the optimum extracting condition,which perfectly met the control standards for pollutants in sludges from agricultural use ( GB4284-1984).While,the water content of recovered oil was 0.3% and reached the processing requirements of domestic refinery.