Anaerobic microbial influenced corrosion of carbon steel in synthetic bentonite pore water a 26 months study

Microbial corrosion of carbon steel in synthetic bentonite pore water inoculated with natural underground water containing microorganisms was studied in a 26-month long-term experiment including sterile controls under anaerobic conditions. Corrosion behaviour was determined using the mass loss method, SEM-EDS analysis and Raman spectroscopy, while quantitative and qualitative changes in the microbial community were analysed using molecular-biological tools. Corrosion rates were significantly higher in the biotic environment, which had a microbial community dominated by nitrate-reducing bacteria. Highest corrosion rates coincided with dominance of Methyloversatilis, suggesting that this bacterium plays an important role in microbial corrosion.