SOLVENT EXTRACTION PROCESS FOR REFINING USED-LUBRICATING OIL

摘要

In accordance with the present invention, a process is provided for removing impurities from heavy and light lube oil fractions that have been obtained from waste lubricating oil. The impurities in the light lube oil fraction are removed utilizing tetrahydrofurfuryl alcohol in an extraction column (10). An oil-rich raffinate has the solvent removed therefrom by steam distillation and stripping at reduced pressure in a distillation tower (20). The heavy lube oil fraction is purified in a manner similar to the purification of the light lube oil fraction. The finished heavy and light lube oil may then be subjected to further treatment, such as polishing steps or additives may be blended into the lube oil product depending on the desired use.