Zawtika Deferment Management Enhancement: A Systematic Way to Unlock Gas Potential for Optimized Operations
Authors: Zar Soe Thin , Leelaratsameephanit Anucha , Chantarataneewat Wiwan , Peerakham Chatchanakorn , Jitputti Phanuwat , Kiatrabile Thanita 
Published: March 2022

PTTEP's Myanmar Asset Zawtika offshore field is located in the Gulf of Moattama, offshore Myanmar, referred to as the Zawtika Gas Development and Production Area. The area lies approximately 300 km south of Yangon and 290 km west of Tavoy on the Myanmar coast. Zawtika offshore gas field consists of Zawtika Processing and Living Quarter platform (ZPQ) which was designed to provide fully automatic, integrated and centralized platform/ process control, and ZWP1 which is connected to ZPQ via interconnecting bridge and 10 remote wellhead platforms which are ZWP2, ZWP3, ZWP4, ZWP5, ZWP6, ZWP7, ZWP8, ZWP9, ZWP10 and ZWP11, located in the Gulf of Moattama offshore Myanmar.

In order to prolong field gas potential, the data analysis, planning and management on daily gas potential loss is important to better understand the field behavior. The issues of gas losses are captured and categorized based on difficulties of recovery. "Deferment" is defined as the short-term temporary reduction in Production Availability which results in delay of gas production due to the effects of system constraints/ limitations, scheduled shut down activities on wells or facilities associated with safety, production, maintenance, operation and unplanned interruptions. "Lock-in" is defined as the long-term gas potential reduction that requires longer time and higher investment to solve and unlock that potential.

Under PTTEP Operation Excellent Management System (OEMS), one of the essential elements for optimized operation is deferment/lock-in potential management. With this importance in focus, this paper discusses Deferment Management Enhancement for PTTEP's Myanmar asset operation which goal is to enhance deferment analysis and management by using data analytics in information technology environment in alignment with PTTEP Digital Transformation direction. The data obtained from this enhancement can be used in short-term and long-term planning activities for production system optimization including project investments, reservoir management and integrated operations planning, and especially in providing in-depth analysis to minimize deferment volume to maximize return on investment.

Production deferment/lock-in guideline is developed within PTTEP's Myanmar Asset to structure Hydrocarbon Availability Model (HAM) for Zawtika according to PTTEP Operations Standard and define deferment and lock-in gas potential data collection basis and their categorizations. ZPDMS deferment module is then enhanced based on this guideline with the extra capability to facilitate site data entry which has been a problem since start-up due to satellite link constraint from Zawtika offshore field. This enhancement also consolidates lock-in/deferment causes, and coding structures, integrates subsurface potential calculation and surface production data, and introduces key visualization pages (e.g. Deferment Dashboard, etc.) for better deferment management performance analysis.

After the full implementation of Zawtika Deferment Enhancement project with the help of a digital platform, the gas potential loss due to deferment can be gained back by unlocking the lock-in potential and reducing the unplanned deferment events by troubleshooting as early as possible from the results of effective deferment analysis and planning. As a result, the yearly average of unplanned deferment was reduced from 68 to 34 MMscfd in 2020 and from 34 to 26 MMscfd in 2021 respectively.