Publications

Rhamnolipid is a potent natural biosurfactant which has a wide range of potential applications, including enhanced oil recovery (EOR). The rhamnosyltransferase 1 complex (rhlAB) is the key enzyme responsible for transferring the rhamnose moiety to the b-hydroxyalkanoic acid moiety to biosynthesize Rhamnolipid in microorganisms like Thermus aquaticus. This study purposes to utilize rhIAB gene for Rhamnolipid production in Thermus aquaticus strain CCM 3348 which was isolated from Barembang, Jambi and investigates the potential of enhancing oil recovery from Talang Akar heavy oil field via hot water injection followed by injection of a chemical surfactant and/or a biosurfactant (Rhamnolipid) produced by a genetically engineered Thermus aquaticus through coreflood experiment. The results reveal that the biosurfactant and the chemical surfactant reduced the residual oil saturation after hot water flood. It was found that the performance of the biosurfactant increased by mixing it with chemical surfactant. It is expected that the structure of the Rhamnolipid used in this study was changed when mixed with chemical surfactant as a probable synergetic effect of biosurfactant chemical surfactants was observed on enhancing oil recovery, when used as a mixture. In conclusion, this work proved that it is more feasible to inject the Rhamnolipid as a blend with chemical surfactant, at the tertiary recovery stage, because the IFT value decreases from 36 mN/m to 0,19 mN/m and cumulative oil recovery is 9% higher than in the secondary recovery stage. This might be attributed to the fact that in the secondary mode, improvement of the macroscopic sweep efficiency is important, whereas in the tertiary recovery mode, the microscopic sweep efficiency matters mainly and it is improved by both surfactants mixture. As evidenced by this study, Rhamnolipid worked better than the chemical surfactant in reducing the residual heavy oil saturation and IFT after hot water flood. Furthermore, this innovation works by increasing oil recovery efficiency and is expected to become a green technology for conventional hydrocarbon production.