140km offshore of Luanda
160,000 barrels of oil a day
Daewoo Shipbuilding & Marine Engineering (DSME), South Korea
The CLOV development project, owned by Angolan state-owned oil company Sonangol, constitutes the Cravo, Lirio, Orquidea and Violeta discoveries, which are situated in water depths of about 1,400m in Block 17 offshore of the African nation.
CLOV is the fourth development pole in Block 17 and is located about 140km from Luanda. The other three former poles include Girassol, Dalia and Pazflo. Production from the block started in 2001.
Total is the operator of the block, holding 40% interest, while Statoil holds a 23.33% share, ExxonMobil holds a 20% share and BP Exploration Angola owns a 16.67% share.
The development of the four fields was approved in August 2010. The fields will have a production capacity of 160,000 barrels of oil per day when they start production in 2014.
Developing the Angolan offshore oil fields
The project comprises of constructing a converted hull floating, production, storage and offloading vessel (FPSO) with 1.8 million barrels of storage capacity. It will also be capable of processing 230 million cubic feet of gas per year.
The project also involves the drilling of up to 34 subsea wells, which will be tied back to the FPSO unit.
Subsea installation works for the project are being carried out by Subsea7. The scope of work for Subsea7 includes the installation of pipes covering a total length of 132km, comprising of a 40km pipe-in-pipe production line, 60km water injection line (including two hybrid riser towers for each line) and a 32km gas export line (including a single hybrid riser).
The contract awarded to Subsea7 also includes the installation of the subsea manifolds and pumps, subsea umbilicals covering 80km, 37spools and 15 jumpers.
The installation works for the subsea equipment are being carried out using Subsea7’s vessels Seven Borealis, Seven Eagle and Acergy Legend. The company will also carry out the pre-commissioning works for the project.
CLOV FPSO construction and design
Construction of the FPSO was carried out by Daewoo Shipbuilding & Marine Engineering (DSME) at its shipyard in Korea. The first steel for the vessel was cut in July 2011. The topsides were installed and the FPSO was delivered in June 2013.
The vessel measures 305m in length, 61m in width and weighs 110,000t. It is designed for 20 years of deployment. The construction of the FPSO required about 88,000 steel plates.
Contracts awarded for the CLOV development project
FMC Technologies is involved in the manufacture and supply of subsea production equipment, comprising of 36 wellhead systems, 19 subsea trees, seven manifold systems and refurbishment works for various ancillary equipments. FMC Technologies’ contract is worth $520m.
The contract to carry out the design works for the topsides of the FPSO was awarded to KBR in October 2010. Metso will supply its stainless-steel valve controllers for the FPSO. POSCO was involved in supplying the steel plates for the construction of the FPSO.
GE will deliver four LM 2500+ G4 SAC aero-derivative gas turbines for power generation and five compressors for the FPSO as part of a $113m contract.
Aker Solutions, in collaboration with Framo Engineering, will supply a 10.6km multiphase power and control umbilical (MPP umbilical) for the project. The MPP umbilical will be used to provide the system functions for the Framo multiphase pump station integrated into the project.
The contract value is NOK80m ($14.4m). Technip has been awarded the contract to deliver 76km of dynamic and static production and water injection umbilicals for the project.
VWS Westgarth, a subsidiary of Veolia Water Solutions and Technologies (VWS), has been contracted by DSME to design, supply and deliver an ultrafiltration system with a capacity of 66,208m³ a day and a sulphate removal package (SRP) system with a treatment capacity of 59,496m³ a day.
Electrical equipments used for the project are being supplied by Converteam. The company will supply five complete variable speed drive systems, including induction motors for the main gas compressors of the FPSO. The electric motors for the water injection pumps will be supplied by Sulzer.
Fairstar Heavy Transport (FAIR) has been contracted by DSME to transport the FPSO components from Angola to Korea for the project. The works are being carried out using FAIR’s semi-submersible vessel FJORD.
HVAC products and solutions, such as valves, fire and gas dampers, monitoring systems, dampers, airflow management and distribution products, were supplied by Halton. The laundry machines for the FPSO were supplied by Loipart.
The PSVM development area is situated in the north-eastern sector of Block 31 roughly 400km from Luanda.
ExxonMobil’s Xikomba deepwater development in Angola, West Africa, is located in the north-west corner of Block 15.