Affiliation:
1. PTT Exploration and Production Public Company Limited, Bangkok, Thailand
Abstract
Abstract
The challenges presented by Microbiologically Influenced Corrosion (MIC) and the resultant losses in primary containment (LOPC) persist as significant issues in the oil and gas industry. Addressing the LOPC concerns requires a comprehensive approach various factors and information. As the digital transformation strategy, a promising solution has emerged MIC problem in one of the forms of "AiMS - AI Asset Integrity Management Solution" manages flowline integrity. AiMS is a successful asset management system in power generation, oil exploration, and refining, ensuring asset performance throughout its lifecycle. The methods maintain asset integrity and reliability, reduce risks, improve performance, and meet standards. MIC mitigation program development and digitalization, flowline integrity assessment, bacteria test validation, and bacteria identification investigations are part of the program.
Bacteria testing procedures are confirmed for accuracy and reliability. The chosen procedures are based on historical data of flowline and well tubing inspection results, and bacteria communities’ analysis. Biocorrosion-prone bacteria are identified through DNA analysis (16S rRNA gene). Sample collection, preservation, SRB enrichment, and DNA extraction of biocorrosion-causing bacteria in field A and field B samples help study MIC microbial communities and biocide dosage mitigation. The bacteria communities’ results indicated that bacteria in both field A and field B asset are a mixture of bacteria. Therefore, SANI-Check and Serial Dilution which detects only SRB is not a suitable technique to monitoring bacteria. The ATP test which detects all bacteria is a better choice.
MIC corrosion depends on flow velocity, pigging frequency, and biocide. Due to late-life fluid production and back pressure, increasing production flow velocity is impractical. A bacteria management guideline and flow chart are available for operation and inspection teams. High-risk flowlines should be biocide injected weekly and cleaned monthly using a brush pig. Weekly biocide injection, sessile bacteria/biofilm monitoring, and compatibility concerns are part of the program. The inhibitory efficacy of biocides, glutaraldehyde, and THPS in SRB-enriched cells was examined. Field B bacteria were more aggressive than Field A bacteria, requiring 750 ppm glutaraldehyde to inhibited growth.
AiMS has five levels: data integration, analytical model, optimization module and process, prediction model, and strategic advice. Engineers and professionals use the AiMS algorithm to understand production facility corrosion and deterioration. AiMS's continuous asset integrity management work cycle helps customers understand their asset's status and visualize data for better decision-making. It explored and developed a method for integrity management optimization based on a novel data structure and format. It has the ability to give recommendations to improve integrity management. The integrity level of equipment and infrastructure increased, resulting in a more reliable production process.
The MIC mitigation scheme has lowered MIC severity, extending the monthly inspection interval for 17 flowlines and lowering corrosion rates. AiMS has generated asset cost saving up to 3.1 million USD in capital and operating costs annually. This category has seen an 80% reduction in manhours due to the AiMS technology, as it has enabled a comprehensive asset integrity management strategy, allowing a transition from costly preventive and corrective maintenance tactics to a more suitable alternative. It improves maintenance and operations while reducing unexpected repairs and simplifies stock and spare part management.