Control of Microbial Induced Corrosion in an oilpipeline- A Case Study

Abstract

Internal corrosion in a pipeline occurs due to various reasons such as water hold up, solid build up, inferior product quality, microbial induced corrosion (MIC) etc. Among these mechanism of corrosion, MIC is one of the most severe form of corrosion in oil and gas pipelines. MIC may lead to fast rate corrosion and cause leakage with a short span of time if not controlled. Therefore, it is a challenge for the pipeline operators to prevent MIC attack in cross country pipelines. The paper evaluates effect of microbial corrosion in one of the crude oil pipeline system. The detailed study was conducted to identify the bacterial corrosion. The study involved extraction of DNA of the microbial species to determine the strength of the microbes present in oil and the type of the species. The findings were compared to the available international database. Effects of the microbes were evaluated in actual samples of crude oil with and without bacteria and the finding verified with  in-field in-line inspection reported data, Based on the findings corrosion growth analysis is carried out for the candidate pipeline. Finally to eradicate harmful bacteria from the pipelines biocide chemicals were designed and tested in the laboratory for their effectiveness and then injectedinto the pipeline and fresh sample drawn from the downstream of the injection point for monitoring the effectiveness of the biocides in an actual pipeline condition.