Late Life Asset Management: Field T Value Optimization as the First Malaysian EOR Asset

Abstract

Abstract Enhanced Oil Recovery (EOR) via Water Alternating Gas (WAG) injection has given a new lease of life to Field T that has been producing for over 40 years. As the first large-scale, full-field offshore implementation of WAG EOR endeavor globally, this development that kicked off in 2014 has presented its fair share of challenges and successes. Since embarking on this journey, the field's capacity has grown by 300% in the span of eight years thanks to three key strategies in wells integrity management, maintaining EOR WAG efficiency and topside reliability maintenance. For wells integrity management, prevention efforts are carried out via periodic downhole corrosion inhibitor injections of identified high-risk wells susceptible to corrosion and erosion. Caliper surveys and noise logs are also carried out to establish a baseline and identify any leaks which will be rectified either via non-rig wellwork intervention or rig workovers. In terms of dynamic reservoir management, detailed surveillance on the Gas-Oil Ratio and watercut is key to determining the optimum duration of water and gas injection cycles. Continuous gas lift optimization is also carried out as the amount of gas lift needed by each well changes between gas and water injection cycles. Lastly, maintaining topside reliability in key critical equipment such as WAG charge pumps, water injection pumps and gas compressor cooling pumps is crucial. This is necessary to maintain the ability to continuously inject gas and water to process the reservoir and sweep more oil. This was carried out via Single Point of Failure assessments and automation to optimize downtime. By implementing these strategies, Field T currently boasts the highest percentage of active strings count in EMEPMI at 71% and improved topside uptime from 10% pre-EOR to less than 5% average post-EOR. The field capacity has also successfully grown by 300% in the span of eight years. Figure 1 3 key strategies and focus areas in maximizing the value of EOR in Field T