SUbsea Projects
S U B S E A
Projects FMC, GERM PLEM for BP
FMC has won a major contract from BP to supply a deepwater manifold and pipeline end terminals, for part of what will become an sophisticated gas gathering system in West Africa. The project could establish Angola as an important LNG hub.
or flared, however, a more costeffective way of gas utilisation is to pipe it onshore. Plans have been laid for 125 million ft3/day to go to the Angolan market with a majority being liquefied and transported in LNG carriers to the Atlantic basin gas markets.
There are four main groups active in Angola’s deepwater offshore sector. In Block 31, BP is currently working on a project which will see the development of the Plutão, Saturno, Vênus and Marte (PSVM) fields.
An LNG plant currently being built at Soyo will be based on a single train with a throughput of 5.2 million tonnes. It is planned to be onstream by 2012. This will require the supply of approximately 1000 million ft3/day of gas. Plans have, therefore, been set out for three strategic pipelines in a phased installation and commissioning programme. This will be the base of a high-pressure gas-gathering network eventually involving 635km of pipelines.
The development consists of a floating production, storage and offloading (FPSO) vessel designed to produce 157 000b/d and a minimum storage capacity of 1.6 million barrels. First oil planned for 2011. In block 18, BP operates the Greater Plutonio field, discovered in 1999 and in production since 2007. Other deepwater producing fields are located in block 15, operated by Exxon and Block 17, operated by Total.
This initial phase involves laying a 74km-long, 12in spur gas export line (GEL) between Greater Plutonio to the ‘PLEM 3A’ which links into a main line between Total’s Girassol field and the LNG
At present, gas associated with these huge oil reserves is injected
Block 31
PLEM3a Block 32/3
“The GERM manifold is equipped with a choke system to control the flow of gas as well as a number of points to inject methanol if required. “A notable feature of the pipeline system is the high gas pressure it must accommodate. The manifold will therefore incorporate a safety instrumented system, which will detect any high-pressure surges and use gate valves to protect the pipeline downstream, which has a lower rate and
GERM manifold
SOYO LNG Block 17/18 Phase 2 Total
Block 17 Phase 1 Total
Gas Gathering System Overview
UT2 AUGUST 2009
“We have experience in building deepwater gas export manifolds for this area,” said project manager Hanne Bakkerud. The most recent was on Rosa for Total.
Block 14 Chevron
Block 15 Gas Gathering and Export ExxonMobil
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plant. This pipeline will then be able to contribute 305 million ft3/day of gas to the Soyo LNG plant. Fundamental to this operation, however, is a gas export regulating manifold (GERM) and the two pipeline end manifolds (PLEM) that will sit either end of the pipeline.
Block 18 Spur Line BP
Closed caisson foundation supporting the GERM and PLEM