METHOD OF REGENERATING EXHAUSTED LUBRICATING OILS Russian patent published in 1999 - IPC

FIELD: lubricating materials. SUBSTANCE: exhausted lubricating oil is treated on heating to 80-90 C at stirring with aqueous solution of alkali metal salt taken in quantity 0.2 to 0.6% based on oil weight for 15 to 30 min maintaining temperature 80-90 C. Then, aqueous solution of soap (0.3- 0.5% of oil weight) is added. Mixture is agitated for 15-30 min to complete emulsification. After settling and cooling, oil is separated from sludge and distilled. Proposed method can be applied on low-scale production plants where separate collection of different-quality oils is provided. EFFECT: essentially simplified technology. 2 tbl