Operational Challenges in Managing High CO2 Content Gas Production in Peninsular Malaysia Operations

Peninsular Malaysia Operations (PMO) plays an important role in supplying gas demand throughout the region since the gas business commencement in 1980’s. Currently about 600 MMscfd gas is supplied by PMO. At the moment, three nonassociated gas (NAG) fields, namely DYG, RSK, and TBC contribute to about 50% of the total gas supply from PMO. Apart from producing NAG, the RSK and DYG fields also serve as network hubs to evacuate gas to the Onshore Gas Terminal (OGT) through two independent gas delivery systems: Joint Delivery System (JDS) and Resak Delivery System (RDS) respectively. The two JDS and RDS gas streams are mixed at OGT and then delivered to the customer processing plant, with a CO2 maximum limit of 8% by mole. Apart from the many operational challenges to sustain gas production, meeting the gas specification proves to be a difficult task, especially for the RDS where TBC gas (with about 30-40% CO2) is to be blended with RSK gas (itself producing about 23% CO2).The TBC gas was put on stream in 2011 and an Acid Gas Removal System (AGRS) was deployed to reduce CO2 content. Prior and upon commissioning of the AGRS facility, feed of CO2 level into the gas network was managed by optimizing the flow rate. This paper describes some major challenges in sustaining the gas production supply and meeting the gas quality requirement. The major operational challenges include subsurface uncertainty and problems, maintaining gas compression reliability, AGRS operations and optimizing the usage of gas pipeline network. To complete the analysis, some commercial aspects are also discussed in the paper.