Kaombo Ultra-Deep Offshore Project involved the development of six of the 12 fields discovered at Block 32, around 260km offshore Luanda in Angola, Africa.
The final investment decision was made in April 2014, which made a further saving of $4bn to the overall investment, earlier estimated at $20bn.
Total operates Block 32 with a 30% stake, along with Sonangol P&P (30%), Sonangol Sinopec International (20%), Esso Exploration and Production Angola (Overseas) (15%) and Galp Energia (5%).
The project is located within an 800km² site in the central and southeast part of the block. The water depth ranges from 1,400m to 1,950m.
The first offshore production unit of the $16bn Kaombo development project was commissioned in July 2018, while the second unit started production in April 2019.
Total production stands at 230,000 barrels a day (bpd), while the estimated reserves of the six wells are approximately 650 million barrels.
Commissioned in April 2008 for commercial production, it is the first ultra-deepwater offshore field of the Republic of the Congo.
Development of the ultra-deep offshore project
Development of the Kaombo Ultra-Deep Offshore Project primarily involved the drilling of 59 subsea oil production wells, which are connected via 300km of subsea lines to two floating production, storage and offloading (FPSO) vessels.
Associated gas from the fields is transferred to the Angola liquefied natural gas (LNG) plant in Soyo.
Two of Total’s large crude carriers, VLCC Olympia and VLCC Antarctica, were converted to create the FPSOs. Each FPSO has an individual oil treatment capacity of 115,000 barrels a day, a water injection capacity of 200,000bpd, a gas compression capacity of 100 million standard cubic feet a day (Mmscf/d), and an oil storage capacity of 1.7 million barrels.
The two FPSO units for the Kaombo project are named Kaombo Norte and Kaombo Sul.
The project’s subsea production system includes 20 subsea manifolds and 65 well-sets with vertical subsea trees, ancillary controls and work-over and tie-in systems.
Offshore vessels for the Angolan ultra-deep offshore project
Heerema’s deepwater construction vessel Balder was deployed to install the STTRs and pipe-in-pipe production pipelines, while Technip’s vessel, the Deep Blue, installed the remaining pipelines.
Technip deployed other vessels from its fleet to install the flexibles and umbilicals, as well as provide construction work support for the ultra-deepwater project.
Bumi Armada’s subsidiaries, Armada Offshore OSV and Bumi Armada (Labuan), were contracted in January 2014 to supply their Armada Tuah 306 and Armada Tuah 302 platform supply vessels to carry out the drilling works within Block 32.
The $3bn engineering, procurement, installation and commissioning (EPCIC) contract for the two FPSOs was awarded to Saipem. The contractual scope includes engineering, procurement and conversion of the tankers, fabrication and integration of the topsides, as well as installation of the mooring systems, including the hook-up.
Saipem was awarded a $1bn contract to operate and maintain the converted FPSO units for seven years.
Petrolis was sub-contracted by Saipem for providing the mooring and hook-up activities associated with the FPSO units.
Sembawang Shipyard, a subsidiary of Sembcorp Marine, was awarded the subcontract worth S$600m ($42.7m) for the conversion of the two VLCCs into two FPSO units.
Bluewater Energy was awarded the engineering, procurement and construction (EPC) contract for the turret mooring systems.
A joint venture (JV) between Technip and Heerema Marine Contractors was awarded the engineering, procurement, construction, installation and pre-commissioning contract for the project’s subsea umbilicals, risers and flowlines. The contract, awarded in April 2014, was worth $3.5bn, with Technip’s share being 55% and Heerema’s share being 45%.
The JV also carried out engineering and installation works for 18 rigid single-top-tension risers, which are large buoyancy tanks measuring 40m by 6m. It installed flexible top riser jumpers, riser base spools, rigid pipe-in-pipe production and single pipe injection pipelines, as well as other subsea structures, piles and steel jumpers.
The deeper and heavier pipe-in-pipe production pipelines range from 12in to 18in in diameter.
“A joint venture between Technip and Heerema Marine Contractors was contracted to carry out subsea engineering and installation works.”
Technip subcontracted TLC for the pre-engineering services related to the subsea development project for two years.
The Nkr14bn ($1.6bn) contract for the supply of the subsea production system was awarded to Aker Solutions. The company further collaborated with Prodiaman Oil Services to carry out the local activities associated with the contract.
DNV-GL was contracted by Total to provide marine warranty services associated with the subsea equipment for the project.