Petroleum and gas products are the major source of energy for industry and daily life. However, oil and gas industry face today to one of the major environmental problems presented by hydrocarbons contamination of soil and water. Various processes in this industry generate different contaminated hydrocarbon wastes, resulting from voluntary or accidental presence of petroleum products during the exploration, production, refining, transport, and storage. Sustainable management of this industrial chain requires a sharp HSE vision, ultimately based on preventing and abating the pollution in order to ensure work safety and to protect environmental components such as water and soil from contaminations and therefore, to develop practical studies in response to potential disasters.
In oil and gas industry, solid and liquid wastes such as process waters or waste waters and contaminated soils contain high concentrations of hydrocarbons, which constitute the major widely distributed environmental contaminants and most of them are biodegradable by various microorganisms. The present study highlights the aerobic degradation of hydrocarbons by a novel indigenous bacterial strain, isolated from a drilling sludge in the south of Algeria. The biodegradation is carried within two kind of matrix; synthetic medium and sand microcosm with crude oil as the sole carbon source during three months.
The results of the bacterial strain characterization can affiliate the isolated strain to Enterrobacter genus, with an emulsification index of 60 %. In the bulk medium, metabolic parameters evolve with time; the bacterial count increases gradually and the pH shows fluctuations in response to the metabolic and environmental changes. The surface tension of the bulk decrease considerably from 60 mN/m to 30 mN/m in less than one month, with a total emulsification of crude oil in the end of treatment. In sand microcosm, pollution parameters change with time and hydrocarbons concentration decreases significantly, with a biodegradation rate of 47.35 % after only three months of treatment.
Therefore, it may be concluded that microbial degradation can be considered as a key component in the cleanup strategy for petroleum hydrocarbon remediation for a good sustainability. Furthermore, our results indicate that the isolated bacterial strain has an exploitable ecologic role, which may potentially be used in the biodepollution of hydrocarbon polluted waters generated by oil and gas industry and in the bioremediation of hydrocarbon contaminated soil of the same industry.
