Su Tu Trang gas field is located in Block 15-1 of the Cuu Long Basin off the southern coast of Vietnam. The offshore gas field lies south-east of Ba Ria-Vung Tau province at a water depth of 50m and about six kilometres away from the existing Su Tu Den field (Black Lion).
The Su Tu Trang gas field, also known as the White Lion, has been in production since 2012.
The gas field is owned and operated by Cuu Long Joint Operating Company (CLJOC), a joint venture of PetroVietnam (50%), Perenco (23.25%), Korea National Oil Company (14.25%), SK Corporation (nine percent) and Geopetrol (3.5%).
Cuu Long Basin Block 15-1 discoveries
Cuu Long Basin is a tertiary rift basin covering an area of 25,000km² in the southern part of Vietnam. The Block 15-1 Petroleum Contract Area is located at the north end of the Cuu Long Basin.
CLJOC acquired operating interest in the block 15-1 in September 1998. Su Tu Den was the first field to be discovered and developed in the basin.
The oil field was discovered in 2000 and brought on stream in 2003. Su Tu Vang was the next field to be discovered in the basin in 2001 and commenced production in 2008.
The Su Tu Trang gas field was discovered in November 2003. Commercial production from the field began in September 2012.
Su Tu Nau field, currently under development, is the latest field to be discovered and developed in the block. Production from the Su Tu Nau field is expected in 2014.
The total estimated recoverable reserves at these four fields are estimated to be 621 million barrels.
Su Tu Trang offshore field infrastructure
The Su Tu Trang well head platform comprises of 1,400t topside, 1,200t jacket and 1,000t of jacket pile. PetroVietnam manufactured the wellhead platform jacket and topside at its fabrication yard in Vung Tau city.
The output of the field is transported through a 19.5km, 12in subsea pipeline via a manifold to the existing Su Tu Vang Central Processing Platform. The Pipeline End Manifold weighs approximately 87t.
Production at the Vietnamese gas field
The gas field currently produces about 45 million cubic feet (mcf) of gas and 7,000 barrels of condensate per day. It has a reserve of 20 billion cubic metres (bcm). The annual gas output of the field is expected to be approximately 2bcm. Production from the field is expected to last until 2023.
The gas produced at the Cuu Long basin is transported to the Phu My Gas Distribution Center via Bach Ho pipeline system.
The Bach Ho-Long Hai-Dinh Co pipeline, part of the Cuu Long Basin Gas Pipeline System, extends across 117km in length.
Contractors involved with the Su Tu Trang field
The engineering, procurement and construction (EPC) contract for the Su Tu Trang gas field development was awarded to PTSC Mechanical & Construction (PTSC M&C), a subsidiary of PetroVietnam Technical Services Corporation, in March 2010.
The $165m contract included the overall project management, procurement and fabrication works.
The contractual scope also included modification works for the Su Tu Vang Central processing platform.
Nippon Steel Engineering was sub-contracted by PTSC M&C for the detailed design, as well as for the offshore transportation and installation works.
The mechanical handling equipment supply contract for the Su Tu Trang’s Wellhead Platform was awarded to Ansell Jones.
PVID provided pipe coating services for the project. Vietnam GloCoating Engineering was awarded the contract for conducting helideck friction testing work.
Bien Dong 1 Project involves the joint development of the Moc Tinh and Hai Thach gas fields situated in the Nam Con Son basin.
The Dai Hung oilfield lies at a water depth of 361ft offshore Vietnam.