Metabolites of an Oil Field Sulfide-Oxidizing, Nitrate-Reducing Sulfurimonas sp. Cause Severe Corrosion

Abstract

Ambiguous reports of corrosion problems associated with the injection of nitrate for souring control necessitate a deeper understanding of this frequently applied bioengineering strategy. Sulfide-oxidizing, nitrate-reducing bacteria have been proposed as key culprits, despite the underlying microbial corrosion mechanisms remaining insufficiently understood. This study provides a comprehensive characterization of how individual metabolic intermediates of the microbial nitrogen and sulfur cycles can impact the integrity of carbon steel infrastructure. The results help explain the dramatic increases seen at times in corrosion rates observed during nitrate injection in field and laboratory trials and point to strategies for reducing adverse integrity-related side effects of nitrate-based souring mitigation.

Comparison of sulfide‐oxidizingSulfurimonasstrains reveals a new mode of thiosulfate formation in subsurface environments

“…In addition, formation of intermediate S 0 would not be expected if sulfide is oxidized via the SOX enzyme system, as the sulfur substrate would remain bound to the SoxYZ enzyme (Friedrich et al ., ; Grabarczyk and Berks, ). Although S 0 formation has been observed in cultures of strain CVO before (Gevertz et al ., ; Lahme et al ., ), to our knowledge this has not been shown for other Sulfurimonas spp. Our results therefore support the general view that formation of S 0 from sulfide oxidation is a common phenotype of this genus (Han and Perner, ).…”

“…While strain CVO is the first Sulfurimonas sp. from an oil reservoir with a complete genome sequence, these and other Campylobacteria are prominent in oil field settings (Hubert et al ., ), where S intermediates are postulated to influence microbe–microbe interactions (Telang et al ., ) and impact corrosion of metal infrastructure (Lahme et al ., ).…”

“…Thus, despite their beneficial role in sulfide bioremediation, the activity of sulfide‐oxidizing nitrate reducers can accelerate steel corrosion (Nemati et al ., ; Lahme et al ., ). In this regard, Sulfurimonas strain CVO is known to produce a variety of potentially corrosive sulfur intermediates, and can cause severe corrosion when nitrite and S 0 co‐accumulate (Lahme et al ., ).…”

“…Stimulation of this activity has been explored for mitigation of oil field souring and corrosion control in large‐scale bioengineering strategies in oil fields (Telang et al ., ; Bødtker et al ., ; Shartau et al ., ; Gittel et al ., ; Vigneron et al ., ; Carlson and Hubert, ). Despite one goal of nitrate injection being corrosion control in oil fields (Hubert et al ., ; Lahme et al ., ), S 0 and other potentially corrosive sulfur compounds are often formed and excreted as intermediates during microbial sulfide oxidation (Brune, ; Frigaard and Dahl, ; Lahme et al ., ). Thus, despite their beneficial role in sulfide bioremediation, the activity of sulfide‐oxidizing nitrate reducers can accelerate steel corrosion (Nemati et al ., ; Lahme et al ., ).…”

“…Despite one goal of nitrate injection being corrosion control in oil fields (Hubert et al ., ; Lahme et al ., ), S 0 and other potentially corrosive sulfur compounds are often formed and excreted as intermediates during microbial sulfide oxidation (Brune, ; Frigaard and Dahl, ; Lahme et al ., ). Thus, despite their beneficial role in sulfide bioremediation, the activity of sulfide‐oxidizing nitrate reducers can accelerate steel corrosion (Nemati et al ., ; Lahme et al ., ). In this regard, Sulfurimonas strain CVO is known to produce a variety of potentially corrosive sulfur intermediates, and can cause severe corrosion when nitrite and S 0 co‐accumulate (Lahme et al ., ).…”