UNDERSTANDING, PREVENTING, AND IDENTIFICATION OF MICROBIAL INDUCED EROSION-CORROSION (CHANNELLING) IN WATER INJECTION PIPELINES

摘要

Frequently, water injection pipelines do not last their design life due to corrosion problems. More often than not, the reason has been 'channelling' or 'grooving' corrosion at the bottom of the carbon steel pipeline. Once this mechanism does manifest itself within a pipeline, it may not be stopped, only slowed and the pipeline is doomed to either constant rupture/repair or enforced retirement as a consequence of corrosion rates proceeding in the order of approximately 1.0 - 2.5 mm/yr. This paper does not attempt to provide the reader with the electrochemical surface chemistry, but show the reader from several case histories how this mechanism manifests. This paper will address inadequate chemical housekeeping, the precursors necessary for initiation of 'microbial induced erosion-corrosion', why it can result in sudden unknown failure. Also discussed will be interpreting and identification of 'channelling' from different intelligent pigging technologies and ways to provide physical evidence to help determine if a Water Injection pipeline has succumbed to 'channelling' without employing an intelligent inspection.