Stimulation of an indigenous thermophillic anaerobic bacterial consortium for enhanced oil recovery

Abstract

Microbial enhanced oil recovery (MEOR) is potentially useful in incremental oil recovery from oil reservoirs beyond primary and secondary recovery operations using microorganisms and their metabolites. In the present study, anaerobic, thermophilic methanogenic consortium TERIL63 was developed from a high temperature oil reservoir in India. TERIL63 was identified with strains of Methanothermobacter thermoautotrophicus and Thermoanaerobacter sp. It can grow in the range of 60–100 °C temperature, 0–5% salinity (NaCl) and 5.0–9.0 pH in methanogenic medium. The novelty of the consortium is to produce gases (14.74 mmol L⁻¹), volatile fatty acids (2037 mg L⁻¹), in 10 days through an optimized recipe, which facilitates the displacement of oil towards the surface. The generated data were successfully exploited as a proof of oil recovery by performing core flood, where TERIL63 showed 15.49% enhanced oil recovery. Thus non-toxic, non-virulent TERIL63 is a promising candidate as an economically sustainable and environmentally safe solution for MEOR application.