Performance evaluation of biosurfactant stabilized microbubbles in enhanced oil recovery

Abstract

Microbubble technology is increasingly finding applications in biomedical engineering, soil remediation and wastewater treatment. Recently, the use of surfactant microbubbles has been studied as an alternate to aqueous solution in pollutant remediation since they have the advantage of improving the contact with the contaminant due to their surface properties. In this research endeavor, the application potential of microbubble suspension generated using a lipopeptide biosurfactant produced by a marine strain of Bacillus megaterium in tertiary oil recovery was investigated. The microbubbles were generated using a high speed homogenizer and their properties such as stability and size distribution were studied. The microbubble suspension was used as flooding agent to recover gear oil from an artificially saturated sand packed column. The performance of microbubbles in tertiary oil recovery was compared with that of aqueous biosurfactant solution. It was found that microbubble suspension generated using biosurfactant had higher oil recovery efficiency (46%) than aqueous solution (36%).\n\nMoreover, the pressure buildup across the sand packed column was fairly low while using microbubble suspension. The increased oil recovery using microbubbles can be attributed to their effective permeation through the pores of sand packed column and closer contact between biosurfactant molecules and oil. Thus, the results obtained in this study convincingly indicate that biosurfactant stabilized microbubble suspension, due to its higher performance and lower injection pressure requirement, can serve as a potentially efficient flooding agent for tertiary oil recovery.