Abstract of the scientific work:
Microbiologically influenced corrosion (MIC) constituents for 20% of the global corrosion costs. The most well-known culprits for MIC are the sulfate-reducing bacteria (SRB), such as members from the genus Desulfovibrio. It has been widely accepted that SRBs can contribute significantly to MIC through the production of hydrogen sulfide (HS-) or in some cases a direct electron uptake from the metal surface (EMIC). However, SRBs are not exclusive and often involved with other microorganisms that may also contribute to MIC, such as methanogens. Methanogens produce methane (CH4) using H2/CO2, formate, methylated amines or acetate. Recently, it was proposed by several researchers that methanogens are capable of EMIC through unknown mechanisms. The studies conducted on methanogen-induced MIC are limited to laboratory conditions and they do not represent environmental conditions. Therefore, the goal of this project is to evaluate methanogenic corrosion using environmentally simulated conditions. This project will first focus on locating the specific environmental conditions that generate the highest corrosion rate using single strains of corrosive methanogen and SRB. Followed by an investigation of antagonistic or synergistic effects on corrosion rates using mixed microbial consortia. Lastly, a detailed characterization of the corrosion products (CPs) on the metal surface after exposure to different microorganisms will be conducted providing an accurate profile of the CPs. This research will provide the first detailed corrosion profile of methanogen-induced MIC by incorporating novel measuring techniques, including the HI-Tension- Core facility system for high throughput environment simulation with online analytics. But it also combines a variety of different techniques, including microsensors, Tof-SIMS, GIXRD, XANES and CLSM. This work will provide a novel view on a traditional problem that can contribute significantly into developing new industrial applications, such as corrosion mitigation.