Process for recovery of hydrocarbon from oil emulsions and oily sludges

The major problem associated with petroleum refineries is the generation of various types of petroleum-field emulsions and oily sludges during recovery of light and heavy crudes. The emulsions as well as oily sludges generated are diverse in chemical composition and their accumulation in the environment creates disposal problems. Hence, management of refinery wastes has become a necessity and recovery of oil from these wastes would be the only environmentally friendly approach. A secondary metabolite of glucose grown Bacillus subtilis has been found to be a potent de-emulsifier. Ninety-eight percent of oil from the oil-in-water emulsion could be recovered using partially purified 0.6 mg/l of de-emulsifier. The same de-emulsifier is also successfully used to recover oil from oily sludges (Indian patent pending). The two-step process involves pretreatment of oily sludge with kerosene and/or methanol followed by recovery of 90% hydrocarbon. The biotechnological process developed is the competitive solutionn for management of petrochemical wastes in view of cost effectiveness and environmental harmony, when compared with the available technology.