GTA LNG project advances with infield pipelay completion

bp PLC has advanced its Greater Tortue Ahmeyim (GTA) LNG project offshore Mauritania and Senegal with completion of the infield pipelay scope.

Allseas noted completion of the work scope with use of the Pioneering Spirit construction vessel in a release Feb. 20. Two months after arriving in the field, production crew welded, scanned, and field joint coated the final piece of pipe for the second 16-in. export gas line, the company said.

Landed in a 2-m target box at 2,400 m water depth, the pipeline will be recovered in J-mode configuration to install the termination assembly. For this, the vessel aft has been fitted with a bespoke J-mode frame with a 1,000-tonne load capacity.

The pipelay scope comprises about 75 km of 16-in. export lines and 10 km of 10-in. CRA infield lines, some of the pipeline infrastructure exceeding 2,700 m water depth, Allseas said. Pioneering Spirit will conclude the offshore works by installing the six outstanding flowline termination assemblies.

GTA Hub

GTA is 120 km offshore in water depth of 2,850 m and holds estimated gas resources of 15 tcf. Phase 1 will export gas from four subsea wells to an FPSO about 40 km offshore at which the gas will be processed and then transported by pipeline to the 2.3-million tonne/year (tpy) floating LNG plant (FLNG Gimi) 10 km offshore where it will be cryogenically cooled in the vessel’s four liquefaction trains and stored before transfer to LNG carriers.

Gimi arrived at GTA field earlier this year (OGJ Online, Jan. 11, 2024; Oct. 5, 2023).

GTA Phase 1 is set to produce around 2.3 million tpy and produce for more than 20 years.

bp is operator at GTA with partners PETROSEN, Société Mauritanienne des Hydrocarbures (SMH), and Kosmos Energy.