Implementation and Performance of a Microbial Enhanced Oil Recovery Field Pilot in Fuyu Oilfield, China

Abstract

Abstract Since 1996, a Microbial Enhanced Oil Recovery (MEOR) field pilot is being conducted as a joint collaborative research project between Japan National Oil Corporation (JNOC) and Jilin Petroleum Group Company Limited (JPGCL) in Fuyuoilfield, Jilin Province, China. The primary objective was to increase oil recovery from a shallow sandstone reservoir that had been waterflooded for over 20 years. Three microbes have been identified, evaluated, and put to test in the reservoir through huff-n-puff tests during which incubating conditions for microbes were optimized in surface facilities. Four tests with molasses only were conducted and evaluated against those with the microbial solution. Also, an advanced gene-targeting bio-technique, PCR-RELP, was applied to quickly identify and monitor the target microbes. Significant reductions in watercut and increase in oil production rate were observed in most wells, and they sustained for over 6 months demonstrating the potential of MEOR process. Tests also confirmed abilities of microbes to survive and propagate under reservoir conditions. Preliminary evaluation of fluid analysis and production data indicates that they help increase formation water viscosity, lower water pH and produce gases, notably CO2. Additional huff-n-puff tests and laboratory studies using cores from two newly-drilled wells are underway. The implementation of the final phase of continuous MEOR flood is planned for mid-1999.