Application of Crude Oil Degrading Micro-Organisms Immobilized in Cellulosic Material for Bioremediation of Crude Oil Contaminated Soil

Abstract In this research, crude oil degrading microorganisms were produced and immobilized in a local cellulosic material (coconut fibre) and the immobilized product was applied in the bioremediation of soil contaminated with crude oil. Coconut fibre (carrier) was collected, processed and characterized for selected relevant parameters (physico-chemical properties) that makes it suitable as carrier for the crude oil degrading microorganisms. Crude oil degrading microorganisms were produced from stock culture through enrichment method and characterized. A bioreactor was designed and locally fabricated. The crude oil microorganisms were mass produced via the use of a bioreactor from the consortium of the three best crude oil degrader. Petroleum Hydrocarbon degrading bacteria were immobilized in coconut fibre which was applied in bioremediation of crude oil contaminated soil. A parcel of land with an area measurement of 144 m2 was contaminated with 380 litres of crude oil (Escravos light) and also treated. Two weeks after contamination, the land was tilled to a depth of 15cm with garden fork and a consortium of petroleum degrading bacteria immobilized in coconut fibres (ratio of 1:1) was applied to the soil. Soil samples were collected on a weekly interval for laboratory analysis of residue hydrocarbon content, physico-chemical properties, microbial count of the treated soil using Gas Chromatography (GC) and other methods of analysis. The results showed that about 91.29% of hydrocarbon content in the original crude oil was removed after seven weeks treatment. The percent of total petroleum hydrocarbon (TPH), poly aromatic hydrocarbons (PAHs), benzene, toluene, Ethyl benzene, xylene, (BTEX), degraded in the contaminated soil were 83.01%, 95.86%, and 95.02% respectively. Results obtained demonstrated the effectiveness of immobilized hydrocarbon degrader in treatment of crude oil polluted.