Recent Successes: MEOR Using Synergistic H2S Prevention and Increased Oil Recovery Systems

Abstract

Abstract Contemporary investigations of Microbial Enhanced Oil Recovery (MEOR) technologies began in earnest in the 1980’s. Since then, numerous programs have examined the reliability of the concepts, processes, and technical efficacy of recovery biosystems. Despite reported successes, MEOR technologies have not been widely accepted by the oil and gas industry as a means to recover residual oil. The Bio-Competitive Exclusion (BCX) biological process has successfully demonstrated significant oil recovery results in mature waterfloods from the deliberate alteration of indigenous reservoir microflora to an anaerobic denitrifying bacteria (DNB) population through the use of nitrate-based formulae as alternate electron acceptors and microbial nutrient. These environmentally safe inorganic salts complement the naturally occurring volatile fatty acids (VFA) in the reservoir and produced waters, selectively stimulating and increasing the targeted DNB. This designed and controlled manipulation of an indigenous DNB population initiates and increases the production of multiple gas, solvent, and surfactant bio-products which have known and demonstrable oil recovery properties. The BCX technology offers a feasible, practical, and very cost effective, tertiary oil recovery system that concurrently controls reservoir and surface system souring. Field data from California, Oklahoma, China, and Canada are presented.