UK supermajor BP was set to receive bid documents this week from rivals battling to land the last major contract on phase one of its Tortue-Ahmeyim floating liquefied natural gas project off Mauritania and Senegal.

Up for grabs is a contract to design, engineer and construct a living quarters and utilities facility, with Asian yards understood to be taking a particular interest in the job.

BP is said to have decided it wants to install the accommodation and utility modules on top of a jack-up sub-structure, having discounted use of a conventional steel jacket.

Among the companies thought to be chasing the order are Cosco Shipping Heavy Industry and CIMC Raffles of China and South Korea’s Daewoo Shipbuilding & Marine Engineering.

There are also suggestions that yards in the Middle East, such as Lamprell, in Singapore and possibly in Europe are taking part, although confirmation was not available at press time.

BP and KBR, its prime engineering contractor on Tortue, concluded a pre-qualification exercise for the platform in February and were known to have sounded out yards in Europe.

An industry source said one continental European yard was asked for budgets for the sub-structure and topsides.

This facility will be installed in about 30 metres of water close to the initial FLNG vessel — to be supplied by Golar LNG under a preliminary agreement signed with BP earlier this year — with both protected from heavy weather and adverse sea states by a purpose-built breakwater. Following the general pattern of BP’s contracting strategy for Tortue-Ahmeyim, the successful bidder for the platform order will first carry out front-end engineering and design studies before the contract is converted into an engineering, procurement and construction order.

The EPC order will likely be formalised later this year to coincide with a final investment decision on phase one of the FLNG project.

The specifications of the jack-up facility are not known but one source said it is “small”.

It is thought the jack-up will be a newbuild, although some sources in the Middle East suggested a conversion is a possibility.

It is not known why BP opted for a jack-up concept instead of a piled steel jacket, but one engineer suggested seabed and soil conditions at location could be unfavourable to piling.

One source also argued that BP may want to move or replace the facility as part of its full-field development plan, a strategy which lends itself to an unpiled structure.

The facility is set to be installed close to — and possibly bridge-linked to — the breakwater.

CH2M (subsequently acquired by fellow US player Jacobs Engineering) will construct the breakwater, while a Franco-Italian consortium of Eiffage Genie Civil Marine and Saipem will carry out FEED work on what is described as the project’s hub and terminal.

Protected by the breakwater, the hub-terminal will comprise berthing facilities for the permanently-moored FLNG vessel and LNG carriers. Once FEED work has completed, BP is set to award Eiffage-Saipem a lump sum engineering, procurement construction and installation contract.

Tortue phase one comprises four subsea wells in 2850 metres of water tied back to a floating production, storage and offloading vessel about 80 kilometres away.

The spread-moored FPSO will be installed in 100 to 200 metres of water and is expected to be a VLCC-sized vessel with a 13,000-tonne deck.

The vessel is expected to handle more than 500 million cubic feet per day of gas and about 20,000 barrels per day of liquids.

Once the well stream has been separated on the FPSO, gas will be piped some 30 kilometres to the FLNG vessel, which has a capacity of 2.5 million tonnes per annum.

BP awarded TechnipFMC a FEED-plus-EPCI contract to provide the FPSO with the vessel to be fabricated by Cosco Shipping Heavy Industry.

A McDermott-GE joint venture is carrying out FEED studies on subsea equipment and will be handed a turnkey contract on project approval.

The subsea workscope covers four wells within a five-kilometre radius of each other tied back to a single manifold.

From there, the well stream will flow about 80 kilometres along a pair of 18-inch flowlines to the FPSO.

This workscope may also include pipelines that eventually could take gas to domestic markets in Mauritania and Senegal.

BP is targeting first production from Tortue-Ahmeyim by late 2021.