(215c) Badak LNG Process Transformation: Challenges in Handling Leaner Feed Gas

Badak LNG plant, located in Bontang, East Kalimantan, Indonesia, has been excellently operated for more than four decades to process rich gas from Mahakam Block Field with average methane content around 83%-mole. Declining feed gas had become the major issue to operational sustainability after reaching maximum production in 2001. In 2016, the number of running trains was four out of eight. The number was predicted to get smaller in the next few years.

Maintaining operational sustainability, in 2017, Badak LNG had committed to receive and handle additional feed gas resource from Eni Jangkrik field which results in the leaner feed gas, potentially up to 96.22%-mole methane content. Considering existing process and facilities, Badak LNG plant has the capability to only handle feed gas with average methane content up to 88.2%-mol. Beyond that number, Badak LNG has to deal with significant issues such as off-spec LNG product heating value, BTEX carry-over, very low fractionation columns turn-down ratio, limited NGL production, etc.

Those concerns were answered by implementing minor plant modifications and process adjustments. Badak LNG had firstly imported and used LPG for external re-injection scheme to maintain LNG product specification. Fractionation columns operation were adjusted to maximize NGL production, maintain fractionation columns turn-down ratio and prevent BTEX carry-over to the downstream process. In brief, significant process transformation was successfully made to allow higher methane content and maximize lean gas receive from Eni Jangkrik Field. By the end of 2017, Badak LNG plant had greatly handled feed gas with almost 91%-mole of methane content which equal to 680 MMSCFD of Eni Jangkrik supply or 1.7 times of single running train capacity. It even has potential to cope with leaner feed gas in the future.