A group led by a unit of Amoco Corp. has let contracts for components for development of its Liuhua 11-1 deepwater oil field in the South China Sea.
Sembawang Engineering Systems, Singapore, a Sembawang Group company, under an $11.5 million contract will fabricate six processing modules for Liuhua 11-1's floating production, storage, and offloading (FPSO) vessel. Bohai Oil, Chiwan province, China, received a $1.3 million contract to fabricate and deliver three 150-250 ton pipe rack modules to be installed aboard the FPSO.
The contracts were awarded through Modec Inc., Tokyo, general contractor for the $650 million Liuhua 11-1 development project off China.
Liuhua 11-1 partners are Amoco Orient Petroleum Co.; China Offshore Oil Nanhai East Corp. (Conhe), a unit of China National Offshore Oil Corp.; and Kerr McGee Liuhua Ltd., a unit of Kerr-McGee Corp..
Processing and production units will be able to handle 65,000 b/d of oil and 290,000 b/d of produced water. Because of the high viscosity and tight emulsion of the field's crude, the process modules to be provided by Sembawang Engineering will include numerous heat exchangers to heat the oil at various stages for better oil-water separation.
In addition to development costs, the Liuhua 11-1 combine expects an $850 million, 15 year production phase starting in 1996 with oil flow of more than 47,000 b/d (OGJ, Apr. 26, 1993, p. 30).
Amoco and Conhe, which discovered the field in 1986, say the deepwater prospect is the largest oil reservoir found in the South China Sea (OGJ, Sept. 28, 1992, p. 23).
DEVELOPMENT PLANS
Lying in 1,000 ft of water about 120 miles south-southeast of Hong Kong, Liuhua 11-1 poses technical challenges that developers expect to meet with a combination of proven offshore production technology.
The field's shallow reservoir is to be developed using 20 subsea wells drilled horizontally through the oil bearing structure to maximize recovery volumes. Oil is to be brought to the surface through a subsea gathering system using electric submersible pumps (ESPs) in the wells. Power and maintenance of the subsea systems will be provided by Liuhua 11-1's FPSO and a floating production system (FPS).
Production from Liuhua 11-1 subsea wells will flow to the FPSO through a subsea pipeline and riser system.
On the FPSO, the three pipe rack modules to be provided by Bohai Oil are to deliver production to first stage separators and transfer fluids between processing stages at various modules and FPSO cargo tanks. Part of the produced crude is to be diverted to a safe fuel treatment unit for removal of hydrogen sulfide and further processing so it can be used for fuel for the FPSO and FPS.
Liuhua 11-1's FPSO will be an oil tanker modified to separate produced oil, gas, and water, store processed oil, flare associated gas, and discharge produced water overboard after removal of entrained oil. The unit, to have about 720,000 bbl of storage capacity, is to offload processed oil to tandem moored shuttle tankers.
The FPS will be a semisubmersible rig equipped to drill, complete, and workover Liuhua 11-1 wells. It is to install and operate the field's subsea manifold system and power generating and distributing equipment to power Liuhua 11-1 ESPS.
FPSO and FPS mooring systems will enable the vessels to remain on station in 100 year storm conditions.
