Bioremediation of crude oil-polluted soil--effect of poultry droppings and natural rubber processing sludge application on biodegradation of petroleum hydrocarbons.

Laboratory bioremediation experiments were carried out on crude oil-polluted soil samples by applying various amounts of poultry droppings and natural rubber processing sludge as nutrient supplements at 29 degrees and using slurry-phase and solid-phase biodegradation techniques. Changes in the total hydrocarbon content of the soil were determined using a spectrophotometric technique as a function of time. It was found that the extent of crude oil degradation in untreated soil samples was markedly lower (by up to 100%) than in the soil samples treated with nutrient supplements. Hydrocarbon degradation efficiency was higher in the slurry-phase than in the soil-phase technique.