Biodegradation of petroleum refinery waste oil sludge

Oil contamination of soil and water is a widespread problem in recent years. Microbiological clean ups of this type of contamination can be advantageous, when compared to other remediation techniques. Bacterial consortium prepared with Pseudomonas sp., Corynebacterium sp., Flavobacterium sp., Bacillus sp. and Micrococcus sp. was tested for the degradation of petroleum refinery effluent treatment plant sludge applied to sterile and non-sterile red soil. The maximum rate of oil degradation (71.23%) was observed in treatment E which is amended with non-sterile red soil, non-sterile sludge and mixed consortium. Among the various amendments, non-sterile red soil contained fewer fungal populations, which have also involved in the degradation process. It is concluded that the mixed consortium can be applied in large-scale sludge degradation, as this process is an economically feasible.