ABSTRACT
An effective microbiologically influenced corrosion (MIC) management program is crucial for sustainable and safe operations of oil and gas assets during the energy transition. Historical field sampling information can be used for MIC management by diagnosing the corrosion threats in different parts of the system, selecting the right corrosion mitigation method, and monitoring the effectiveness of applied mitigation measures. A comprehensive analysis of field samples related to microbiological abundance, microbiological activity, microbiological community composition, corrosion/pitting rates, pit initiation morphology, chemical conditions, design and operating conditions, corrosion products, and failure history was used to diagnose the threat of MIC in a complex heavy crude production operation. This chapter includes an in-depth discussion of the operations of a heavy crude production asset that was experiencing internal corrosion in certain parts of the operation. First, a detailed assessment of the possible corrosion mechanisms and severity of MIC in different parts of the system is presented. The potential for MIC varied significantly across the system. Variability in MIC severity was also observed, based on the operating conditions, with no-flow periods presenting higher rates of MIC as compared to flowing operations. Next, the conclusions of the corrosion assessment and recommended changes to the corrosion monitoring and mitigation programs are highlighted, in consideration of differences between different parts of the system and also changes in operating conditions. Lastly, the recommended changes to field sampling and future monitoring based upon the corrosion mechanisms and the severity of MIC are discussed.
