Abstract
Microbially Influenced Corrosion (MIC) was suspected to be the root cause of corrosion problems in Pan American Energy (PAE) oilfields in the San Jorge Gulf area. An integrated and innovative program was proposed to address the MIC issues encountered. It consisted of microbial field audits with advanced diagnostics analyses (investigate), and biocide evaluations under field conditions (remediate). A combination of qPCR and next generation sequencing analyses performed indicated an increasing abundance of Bacteria and Archaea, when moving from production wells to oil storage tanks, and strongly suggested that microorganisms played a major role in the corrosion failures. Consequently, a biocide efficacy study was conducted using field water samples and associated indigenous microorganisms as the test inocula. Thirteen biocide systems, including non-traditional products for the oil and gas market, at three different concentrations were evaluated to determine an excellent choice for disinfecting (rapid kill), to alleviate initial bio-burden, along with a longer term protection for the down-hole reservoir. Two formulations, PAE–A (Glutaraldehyde + THNM)) and PAE-E (THPS + THNM) were found to be the most effective and met the criteria of both rapid kill and long term protection in the lab. The microbial solution PAE-E is now in the process of being validated in a three month field trial.
