Biodegradation of petroleum hydrocarbons in a polluted soil as mediated by a natural biodegradable product

The major part of soil petroleum hydrocarbon pollution is derived from the spillages related to the use and transportation of petroleum products. It is known that the main microorganisms consuming petroleum hydrocarbons are bacteria, so in this paper are presented the results obtained in a bioremediation laboratory experiment. A natural biodegradable product and bacterial inoculum was used for total petroleum hydrocarbon (TPH) removal from an artificial polluted soil. Soil polluted with 50000 mg/kg of TPH was treated with 50 g (0.25%), respective 100 g ECOSOL/20 kg polluted soil (0.5%) and/or bacterial inoculum to increase the biodegradability rate. Also, the soil contaminated with 100000 mg/kg of TPH was treated with 100 g (0.5%), respective 200 g ECOSOL/20 kg polluted soil (1%) and/or bacterial inoculum. The highest TPH removal was obtained with a treatment consisting in 100 g ECOSOL/20 kg polluted soil (0.5%) and bacterial inoculum in case of 5 % TPH and 200 g ECOSOL/20 kg polluted soil (1%) and bacterial inoculum in case of 10 % TPH, corresponding with the highest rates of microbial respiration and the greatest increases in bacterial counts. At each phase of the study, the natural biodegradable product was found to significantly enhance the biodegradation of petroleum hydrocarbons.