Microbes facilitate crude oil production in plateau oilfields

Abstract

Crude oil production has been enhanced using microbial-enhanced oil recovery (MEOR) in many oilfields. After over six years of MEOR test and field application in high-salt environments and unconventional oil reservoirs of plateau oilfields, MEOR mechanisms of emulsification, surface tension reduction, petroleum degradation, and reservoir microbial community structure adjustment were developed. Based on the core MEOR mechanisms of microbes, we carried out paraffin wax removal, single-well huff-puff, and microbial flooding in the Qinghai oilfield, thereby increasing oil production and sustaining economic benefits. These results demonstrate that microorganisms can be enhanced and applied in oilfields with large temperature differences, high salinity, and unconventional reservoirs.

Keywords

Microbial-enhanced oil recovery / Bacillus / Microbial-oil displacement agent / Unconventional reservoirs / Plateau oilfields

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