A Full System Audit of a Gas Production Facility to Ascertain the Cause and Provide Solutions to a Severe Microbiologically Influenced Corrosion (MIC) Threat

Abstract

A Full System Audit of a Gas Production Facility to Ascertain the Cause and Provide Solutions to a Severe Microbiologically Influenced Corrosion (MIC) Threat

Microorganisms associated with Microbiologically Influenced Corrosion (MIC) were detected in an East African gas production facility at levels that represented a serious threat to the future integrity of the facility. Therefore, a full physico-chemical, microbiological and molecular microbiological audit was conducted. Samples were taken throughout the system, from productions wells, through the processing plant, right through to the produced water disposal wells, to ascertain the root cause of the problem.

This paper outlines the integration of a range of analytical techniques used (e.g. volatile fatty acid (VFA), total organic carbon (TOC), inductively coupled plasma mass spectrometry (ICP-MS) and molecular microbiological methods (MMM) analyses), and results obtained. This integrated approach allowed the cause of the problem to be identified. A symbiotic relationship was found to exist between sulfate-reducing bacteria, methanogens, Clostridia and Acetobacteria, which was thought to be causing the severe MIC observed. This enable proactive recommendations to be made to secure the integrity of this important facility.