Sponsors:  Amoco, Arco, Chevron, Conoco, Exxon

Project goals:  Discover whether souring is connected to microbial activity; develop methods for the control and elimination of microbial souring of oil and iron sulfide plugging both within oil-bearing formations and at above-ground facilities

Background:  Oil souring results from the metabolic activity of sulfate reducing bacteria (SRB) that use sulfate (present in formation water and/or injected seawater) as an electron acceptor to produce hydrogen sulfide (H₂S). the toxicity and corrosivity of H₂S in oil and natural gas necessitates costly scrubbing equipment and frequently causes downtime for equipment maintenance. The iron sulfide that typically accompanies SRB activity frequently clogs formation pores, resulting in lower product yields.

Results:  Development of a strategy for control of SRB in above-ground equipment (tanks, pipelines) and an injection treatment to control SRB activity in the subsurface.  Field tests: In field application at oil and gas wells, SRB were inhibited in both surface facilities (production separation equipment) and in the subsurface for a period of greater than six months in both oil and gas wells.

Follow-up:  Further laboratory and field application of this technology is currently under way with sponsor companies.