Enhanced recovery through subsea compression at Gullfaks
This technology adds 22 million barrels of oil equivalent to the production from the Gullfaks South Brent reservoir. The partners will invest some NOK three billion in the technology project scheduled to be completed in the autumn of 2015.
“Innovation and technology development are essential to improved oil and gas recovery and extended life for the fields on the Norwegian continental shelf. The development of subsea compression and processing is a central part of Statoil’s technology strategy for long-term production growth,” says Statoil’s executive vice president for Technology, Projects and Drilling, Margareth Øvrum.
Margareth Øvrum, Statoil’s executive vice president for Technology, Projects and Drilling.
The Gullfaks project is the second large subsea gas compression project planned by Statoil. In April this year the plan for development and operation for Åsgard subsea compression was approved by the Norwegian Parliament.
Both projects are scheduled to be compled in 2015. Furthermore Statoil is responsible for the technology qualification for Shell for a third not yet decided project, the Ormen Lange pilot. There are good synergies between the different projects.
Subsea gas compression is an important step on the road towards Statoil’s ambition of installing the elements for a ”subsea factory”. Subsea processing is key to getting access to resources in Artic areas and deepwater assets.
For the Gullfaks field the investment decision means that platau production can be sustained for a longer period.
Jannicke Nilsson, Statoil’s head of operations in the North Sea west region.
Around 2015 the natural pressure in the Brent reservoir on the Gullfaks South field will be reduced. In order to maintain platau production compression will therefore be required.
“Subsea gas compression will have great effects for the Gullfaks field. Thanks to this technology combined with conventional low-pressure production in a later phase the recovery rate for gas from Gullfaks South Brent can be increased from 62 to 74 percent,” says Jannicke Nilsson, Statoil’s head of operations in the North Sea west region.
Solution for more fields
The chosen technology is a typical solution that may be used for small and medium-size fields due to the compressor size. The consept may be used both for new and existing fields, and Statoil is identifying more potential candidates.
- The technical solution consists of two 5 megawatt wet gas compressors installed in a subsea template at 135-meter depth. They will be tied in to existing templates and pipeline systems 15 kilometres from Gullfaks C.
- Power and control modules will be integrated on the Gullfaks C platform.
- Framo Engineering has been awarded the contract for engineering, procurement and construction (EPC) of the compressor station, including topside power and control systems for Gullfaks C
- Nexans has been awarded the EPC contract for the 16-kilometre power and control cable from Gullfaks C to the subsea compressor station