Used oil regeneration by distn. and further treatment - using distn. bottoms as heat source for further treatment

摘要

Regeneration of used oils is carried out by (a) distilling the oil at a temp. of at least 260 (pref. 260- 420) deg.C, and (b) subjecting the residue to at least one additional treatment to remove one or more contaminants. The improvement comprises using part of the distn. residue as a heat carrier to supply heat to at least one of the treatments in step (b) before recycling it to step (a). The improvement provides greater thermal efficiency and avoids thermal degradation problems associated with heat carriers circulating in closed circuit.