The Sao Vang and Dai Nguyet gas and condensate fields are located in Blocks 05-1b and 05-1c in the Nam Con Son Basin, approximately 300km south-east of Ho Chi Minh City, offshore Vietnam.
Blocks 05-1b and 05-1c were previously owned by Idemitsu Kosan (35%), JX Nippon Oil & Gas Exploration Corporation (35%), and Teikoku Oil (30%). The current owners of the blocks are Idemitsu Kosan (43.08%), Teikoku Oil (36.92%) and Vietnam Oil and Gas Group (20%). Idemitsu Kosan is the operator of the offshore development.
The field development plan was approved by the Vietnamese Government in 2017. First gas from the development is expected in the third quarter of 2020.
The fields are estimated to produce up to 1.5 billion cubic metres of gas per year and 2.8 million barrels of crude oil and condensate per year.
Exploration in Blocks 05-1b and 05-1c
The production sharing contract for the Blocks 05-1b and 05-1c was signed in October 2004 by the partners of the blocks and Vietnam Oil and Gas Group (Petrovietnam). The blocks cover an area of approximately 1,570km² and lie in water depths of approximately 120m.
Seismic surveys on the blocks were carried out until October 2007. An exploration well, 05-1c-DN-1X, was drilled in August 2010. The well reached the target depth in October 2010 and encountered oil and gas in the Dai Nga structure. Drill stem tests carried out on the well confirmed oil and gas accumulations.
Another well was spud in August 2012 that discovered oil and gas accumulations. Drill stem tests on the well were carried out between February 2013 and April 2013.
The partners drilled another well in February 2014, which discovered gas and condensate. Drill stem tests on the well were carried out between May 2014 and August 2014.
Blocks 05-1b and 05-1c reserves
A detailed reserves evaluation was conducted on the blocks, which confirmed commercial viability for the reserves.
The discovered petroleum initially in place (DPIIP) for the blocks is estimated to be 75.7 million barrels of oil equivalent (Mboe), 343.7 billion cubic feet (bcf) of natural gas and 18.4 million barrels (Mbbl) of natural gas liquids.
Sao Vang and Dai Nguyet gas fields development details
The Sao Vang field and Dai Nguyet field will be developed under the project.
The first phase of the field development comprises installation of a new central processing platform (CPP) called Golden Star at the Sao Vang field.
The CPP will be connected to an unmanned wellhead platform via internal pipeline system and will be supported on a jacket structure, weighing 12,733t. The CPP features production well slots, support dry trees, two compressor trains, and two boosters.
The gas from the offshore CPP will be transported to an onshore terminal at Dinh Co via the Nam Con Son 2 pipeline. The condensate from the fields will be exported to the Dai Hung floating production unit (FPU).
A 97m long flare tower, weighing approximately 290.02 metric tonnes, will be developed onshore at PV-Shipyard.
The Dai Nguyet field will be developed using a wellhead platform supporting dry trees. The field will also have a subsea system that will tie-back the production from the Dai Nguyet field to the Sao Vang platform, using a subsea pipeline.
Aker Solutions was contracted to carry out the front-end engineering design (FEED) work for the development.
PetroVietnam Technical Services Corporation (PTSC) will supply a floating storage and offloading (FSO) unit for the project.
PTSC Mechanical & Construction subcontracted MAN Diesel & Turbo to deliver two compressor trains for the offshore platform. The company subcontracted McDermott for the transportation and installation of central processing platforms, wellhead platform, jacket, topside float-over, pipelines, subsea power cables and for providing related services.
PV-Shipyard was subcontracted for the fabrication of the Sao Vang CPP flare tower onshore.
Tam Phuc supplied IMI-CCI control valve and B&R pressure relift valve for the development of the project.
Malaysia Vietnam Offshore Terminal (MVOT) is the engineering, procurement construction, installation & commissioning (EPCIC) contractor for the conversion and operation of the FSO.
Other suppliers include Ultramarine Europe, PVGAS, Ale, SynergenOG, Technip, and Offshore Lifting Equipment Services Joint Stock Company (OLES JSC).