Research Article
Oil Recovery From Fuel Oil Storage Tank Sludge Using Biosurfactants
| Tânia M. S. Lima*, Andréia F. Fonseca, Bruna A. Leão, Ann H. Mounteer, Marcos R. Tótola and Arnaldo C. Borges | |
| Environmental Biodiversity and Biotechnology Laboratory, Microbiology Department, Federal University of Viçosa, 36571-000 – Viçosa, Minas Gerais, Brazil | |
| Corresponding Author : | Dr. Tânia Maria da Silva Lima Environmental Biodiversity and Biotechnology Laboratory Microbiology Department, Federal University of Viçosa Viçosa, Minas Gerais, Brazil Tel: +55-31-3899-2903 Fax: +55-31- 3899-2953 E-mail: tlima@vicosa.ufv.br |
| Received June 13, 2011; Accepted September 16, 2011; Published September 18, 2011 | |
| Citation: Lima TMS, Fonseca AF, Leão BA, Mounteer AH, Tótola MR(2011) Oil Recovery From Fuel Oil Storage Tank Sludge Using Biosurfactants. J Bioremed Biodegrad 2:125. doi: 10.4172/2155-6199.1000125 | |
| Copyright: © 2011 Lima TMS. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. | |
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Abstract
The petroleum industry generates large amounts of solid and semisolid wastes known as oily sludges. The composition of oily sludge varies due to the large diversity in the quality of crude oils, differences in the processes used for oil–water separation, leakages during industrial processes, and also mixing with the existing oily sludge. Usually, the oily sludge contains water, sand, oils, grease, organic compounds, chemical elements, and metals. Those sludges can be generated in several steps of the petroleum production and refining, such as in oil/water separation steps and in the bottom of tanks. The accumulation of oily residues in petroleum industry poses a serious environmental problem. The purpose of this work was evaluate an alternative process to removal of oily sludges through the use of biosurfactants to reduce the viscosity and promote formation of oil/water emulsions making sludge pumping easier and permitting crude oil recovery after breaking the emulsion. Five bacterial isolates were selected for their biosurfactant production potential after screening microorganisms recovered from oil-contaminated sites. Supernatants obtained from autoclave cell suspensions (hereby referred to as autoclaved-supernatant) were mixed with oily sludge collected from fuel oil storage tanks to a final concentration of 0.01%, in order to separate the oil from the inert material. The process proved to be highly efficient for oil recovery, and resulted in up to 95% reduction in sludge volume. The use of cell-free supernatant medium obtained from biosurfactant-producing bacterial strains to treat oily sludges may be an economically and environmentally viable technology, considering the small volume of microbial culture required for the treatment.
