A Technical Feasibility Analysis to Apply Pseudomonas aeroginosa MR01 Biosurfactant in Microbial Enhanced Oil Recovery of Low-Permeability Carbonate Reservoirs of Iran

The effect of an efficient biosurfactant produced from Pseudomonas aeroginosa MR01, a bacterial strain isolated from oil excavation areas in southern Iran, on the recovery of residual oil trapped within carbonate rocks, was investigated. In a core holder set-up, bearing a number of limestone- and dolomite-containing core samples, biosurfactant flooding resulted in oil recoveries as large as 20% to 28% Residual Oil (RO). Biosurfactant injection in less permeable rocks in a range of 0.5 to 32 md was more successful, in terms of oil production. In the case of the least oil recovery via biosurfactant flooding, incubation of the core with a biosurfactant solution at reservoir conditions, increased the recovery from 13% residual oil at zero resting time to 15% after a resting time of one week and to about 30% after a resting time of about two weeks. Based on interfacial tension measurements, salinity and, to a larger extent, biosurfactant reduced interfacial tension. When salinity increased from 170000 to 200000 ppm, the fraction of residual oil production increased to about 20%.