ABSTRACT
Microbiologically influenced corrosion (MIC) is a critical phenomenon, wherein microbial activities induce and accelerate the degradation of both metals and non-metals. This complex biogeochemical process involves the formation of biofilms that alter electrochemical conditions such as pH, redox potential, and ion concentration, leading to localized corrosion, pitting, and metal dissolution. MIC accounts for significant economic losses, particularly in the oil and gas industry, where it contributes to 20% of pipeline corrosion, causing leakages and infrastructure failures. Offshore oil facilities and pipeline networks provide nutrient-rich, anoxic conditions that promote the growth of corrosion-inducing microorganisms. Diverse microbial groups, including sulfate-reducing bacteria (SRB), methanogens, and iron-oxidizing bacteria (IOB), have been implicated in MIC. IOB, as early colonizers, facilitate iron cycling and enhance corrosion over time. Hence, MIC is challenging to predict and control, due to the dynamic and complex nature of microbial colonization and activity. Despite advancements in understanding MIC mechanisms, knowledge gaps remain regarding microbial ecology and interactions under diverse conditions. This chapter highlights the mechanisms of MIC, focusing on the role of IOB and their implications in corrosion, particularly within the oil and gas industry.
