Combatting oil reservoir souring through a predictive understanding of the ecophysiologyand functional diversity of nitrate-reducing bacteria
Oil reservoir souring is the production of toxic hydrogen sulfide by sulfate-reducing microorganisms (SRM) through naerobic respiration supported by organic electron donors present in oil fields. In recent years, nitrate injection has merged as a promising green biotechnology that has been proven effective in controlling sulfide production in oil fields. This strategy relies on inducing nitrate-reducing bacteria (NRB), which can outcompete SRM for organic lectron donors. However, reports of enhanced localized corrosion associated with nitrate injection have started causing concern among oil companies. This research will test the hypothesis that a related NRB-governed process, nitrate-dependent, Fe(II) oxidation (NDFO), plays a role in oil field ecosystems and contributes to biocorrosion in presence of nitrate. The proposed industry collaboration will therefore assess the functional diversity of oil field NRB in context of souring and corrosion, and provide the first ever investigation of the role of NDFO in reservoir souring control.