Scale up and Application of Biosurfactant from Bacillus subtilis in Enhanced Oil Recovery

• Published in: Applied biochemistry and biotechnology 2010-09, Vol.162 (2), p.510-523
• Main Authors: Amani, Hossein, Mehrnia, Mohammad Reza, Sarrafzadeh, Mohammad Hossein, Haghighi, Manouchehr, Soudi, Mohammad Reza
• Format: Article
• Language: English
• Subjects: Agricultural land; agricultural soils; Bacillus subtilis; Bacillus subtilis - growth & development; Bacillus subtilis - metabolism; Biochemistry; Biological and medical sciences; Biology; Biomass; Bioreactors; Biotechnology; Chemistry; Chemistry and Materials Science; Fundamental and applied biological sciences. Psychology; Industrial Microbiology - instrumentation; Industrial Microbiology - methods; Methods. Procedures. Technologies; Oil recovery; Oils - chemistry; Oils - isolation & purification; Oxygen transfer; petroleum; provenance; soil bacteria; Surface-Active Agents - analysis; Surface-Active Agents - chemistry; Surface-Active Agents - metabolism; Surfactants; Various methods and equipments; yields
• ISSN: 0273-2289; 1559-0291
• DOI: 10.1007/s12010-009-8889-0

There is a lack of fundamental knowledge about the scale up of biosurfactant production. In order to develop suitable technology of commercialization, carrying out tests in shake flasks and bioreactors was essential. A reactor with integrated foam collector was designed for biosurfactant production using Bacillus subtilis isolated from agricultural soil. The yield of biosurfactant on biomass (Y p/x), biosurfactant on sucrose (Y p/s), and the volumetric production rate (Y) for shake flask were obtained about 0.45 g g⁻¹, 0.18 g g⁻¹, and 0.03 g l⁻¹ h⁻¹, respectively. The best condition for bioreactor was 300 rpm and 1.5 vvm, giving Y x/s, Y p/x, Y p/s, and Y of 0.42 g g⁻¹, 0.595 g g⁻¹, 0.25 g g⁻¹, and 0.057 g l⁻¹ h⁻¹, respectively. The biosurfactant maximum production, 2.5 g l⁻¹, was reached in 44 h of growth, which was 28% better than the shake flask. The obtained volumetric oxygen transfer coefficient (K L a) values at optimum conditions in the shake flask and the bioreactor were found to be around 0.01 and 0.0117 s⁻¹, respectively. Comparison of K L a values at optimum conditions shows that biosurfactant production scaling up from shake flask to bioreactor can be done with K L a as scale up criterion very accurately. Nearly 8% of original oil in place was recovered using this biosurfactant after water flooding in the sand pack.