A process of biodegradation of hydrocarbons using a plant growth promoting rhizobacteria (PGPR) consortium mixed with the oily sludge, The PGPR consortium is created by inoculating a nutrient broth with pure culture of isolated bacterial strains of Bacillus pumilus, Bacillus subtilis, Pseudomonas putida and Exiguobacterium at Optical Density 1 at 660 nm and bacterial density of 106 cells/ml, and incubating the inoculated nutrient broth in a shaker incubator for forty-eight to seventy-two hours at 150 rpm.
