Carbon steel corrosion by bacteria from failed seal rings at an offshore facility

• Published in: Scientific reports 2020-07, Vol.10 (1), p.12287-12287, Article 12287
• Main Authors: Salgar-Chaparro, Silvia J., Darwin, Adam, Kaksonen, Anna H., Machuca, Laura L.
• Format: Article
• Language: English
• Subjects: 631/326/2565; 631/326/46; 639/301/1023/1026; 639/301/299/892; Anaerobic conditions; Artificial seawater; Bacteria; Bacteria - classification; Bacteria - genetics; Biofilms; Carbon - chemistry; Carbon steel; Chemical analysis; Corrosion; Humanities and Social Sciences; Microbiota; Microorganisms; Molecular Typing; multidisciplinary; Phylogeny; RNA, Ribosomal, 16S; rRNA 16S; Science; Science (multidisciplinary); Seawater; Seawater - microbiology; Steel; Steel - chemistry; Water analysis
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-69292-5

Corrosion of carbon steel by microorganisms recovered from corroded seal rings at an offshore floating production facility was investigated. Microbial diversity profiling revealed that communities in all sampled seal rings were dominated by Pseudomonas genus. Nine bacterial species, Pseudomonas aeruginosa CCC-IOB1 , Pseudomonas balearica CCC-IOB3 , Pseudomonas stutzeri CCC-IOB10 , Citrobacter youngae CCC-IOB9 , Petrotoga mobilis CCC-SPP15 , Enterobacter roggenkampii CCC-SPP14 , Enterobacter cloacae CCC-APB1 , Cronobacter sakazakii CCC-APB3 , and Shewanella chilikensis CCC-APB5 were isolated from corrosion products and identified based on 16S rRNA gene sequence. Corrosion rates induced by the individual isolates were evaluated in artificial seawater using short term immersion experiments at 40 °C under anaerobic conditions. P. balearica, E. roggenkampii, and S. chilikensis, which have not been associated with microbiologically influenced corrosion before, were further investigated at longer exposure times to better understand their effects on corrosion of carbon steel, using a combination of microbiological and surface analysis techniques. The results demonstrated that all bacterial isolates triggered general and localised corrosion of carbon steel. Differences observed in the surface deterioration pattern by the different bacterial isolates indicated variations in the corrosion reactions and mechanisms promoted by each isolate.