METHOD OF OILY FRACTION SELECTIVE REFINING Russian patent published in 1996 - IPC

FIELD: oil refining. SUBSTANCE: oily fraction is added to middle part of extractor and contacted with solvent which is fed to upper part in the presence of antisolvent feeding to bottom part of extractor. Solvent is regenerated and raffinate and extract were obtained and the latter is subjected for distillation off and vapor and liquid phases were isolated. Vapor phase is cooled and the first extract fraction is obtained. Part of liquid phase is added to extractor between raw and antisolvent feeding at temperature not exceeding that of raw feeding to extractor. Remained part of liquid phase is removed as the second extract fraction. EFFECT: improved method of refining. 9 tbl, 2 dwg