Top-down enrichment of oil field microbiomes to limit souring and control oil composition during extraction operations

Abstract

Microbial processes sour oil, corrode equipment, and degrade hydrocarbons at an annual global cost to the oil and gas industry of nearly $2 billion. However, top-down control of these microbial processes can reduce their damage and enhance oil recovery. Here, we screened microbial communities from five oil wells in the Illinois basin and evaluated nutrient injection strategies to control metabolism and community composition. Molasses with molybdate supplementation stimulated gas and organic acid production while suppressing corrosive H2S formation in samples from two wells. These changes were accompanied with significant reshaping of the microbiome community. Simulations of field operations via a lab-scale mini-coreflood validated that oil well microbiomes can be engineered to inhibit deleterious H2S and shape oil hydrocarbon composition in situ. These pilot studies validate the economic potential and sustainability of top-down approaches for microbiome engineering to control microbes in oil extraction and enhance the economic viability of oil recovery.