SLB OneSubsea was selected by ExxonMobil Moçambique to supply the subsea production systems for the first phase of Rovuma LNG, in Area 4 offshore Mozambique.
The contract covers subsea trees, manifolds, umbilicals, and control systems, as well as engineering, procurement, fabrication, and installation support services.
The award is made on behalf of the Area 4 partners: ENH, CNPC, Eni, KOGAS, and XRG. OneSubsea’s scope forms part of a chain of contracts moving the project from planning toward effective construction readiness, after ExxonMobil and its partners awarded approximately $1.1 billion in pre-investment contracts for critical long-lead equipment.
Rovuma LNG Phase 1 includes 18 subsea wells installed at depths of up to 1,700 meters and approximately 50 kilometers of offshore flowlines to transport gas to the onshore liquefaction facilities. The Afungi plant will have a planned capacity of 18.6 million tonnes per year of LNG.
The subsea tree is the first production link
In a deepwater development, the subsea tree constitutes the interface between the well and the production system. Its function is to control flow, pressure, and well access, while manifolds enable grouping and distribution of production from different wells toward the lines that will transport gas to the surface.
Umbilicals complement that architecture by supplying control functions and services from the topsides facilities to the subsea equipment. Therefore, OneSubsea’s award does not simply represent the purchase of individual components: it integrates elements that must operate in coordination within a system subjected to pressure, temperature, mechanical loads, and deepwater operating conditions.
Design takes on special importance because Rovuma LNG will use a network of 18 wells and subsea flowlines to feed a processing facility of enormous scale. A disruption in any of the main elements of that chain can reduce supply capacity to the LNG plant.
From subsea reservoir to LNG plant
The project architecture allows visualization of the complete chain. Gas begins in the Area 4 reservoirs, is produced through the subsea wells, is gathered in the network of manifolds and flowlines, and subsequently reaches the onshore facilities where it will be treated and liquefied.
ExxonMobil proposes an LNG plant based on 12 electrically driven liquefaction modules, each with a capacity of approximately 1.55 million tonnes per year. The complex will also include a combined-cycle power plant to supply the necessary energy to the facilities.
The connection between upstream and midstream is therefore critical. OneSubsea’s contract resolves part of the subsea interface, while other contracts cover the flowlines, construction, and processing facilities. In September, ExxonMobil selected a consortium of Saipem and Jan De Nul for the EPCI contract for the upstream segment, which includes planning for the 18 wells and the subsea network.
Mozambique incorporates permanent subsea capacity
One of the most interesting elements of the contract is OneSubsea’s decision to establish a service base in Mozambique. The facility will provide support to offshore operators in the region and provide local training and employment opportunities, in addition to contributing to the development of specialized suppliers and services.
The industrial importance of this decision extends beyond Rovuma LNG. Deepwater operations require maintenance, intervention, inspection, logistics, and specialized personnel throughout productive life. A local base can reduce response times and favor progressive transfer of technical capabilities to the Mozambican market.
The project itself contemplates approximately 7,500 opportunities for Mozambican workers during its execution and about 700 jobs during the operational phase, according to ExxonMobil. The development also aims to generate economic activity and consolidate infrastructure related to the energy sector.
SOURCE and PHOTO: https://www.worldoil.com/
