The biotreatment of an industrial waste oil condensate has been investigated. The waste is an oily emulsion resulting from chemical processing and condensation of grease trap wastes and industrial waste oils. The oil consists of a complex mix of hydrocarbons with significant fuel oil and lube oil fractions. Currently this waste is disposed of by incineration. The feasibility of using a biological pretreatment process to remove a significant proportion of the hydrocarbons has been investigated.
Enrichment cultures produced a stable bacterial consortium. Flask cultures of this enrichment culture were capable of rapid emulsification of the oil. Within 10 days, 40–50% of the oil waste was degraded. Degradation was monitored using gas chromatographic analysis with flame ionisation detector (GC-FID) and by assessment of microbial dehydrogenase activity using triphenyl tetrazolium chloride (TTC) dye reduction.
The enrichment culture consisted of 9 component organisms, 7 Gram negative and one Gram positive organisms. Their degradative abilities in monoculture have been investigated. Degradation of the waste using monocultures was monitored using GC-FID analysis of the Pristane:C17 ratio in the waste. The degradation capability of each of the component organisms in pure culture was similar to that of the consortium.