Knut Nyborg Head of Front End at Aker Solutions template structure. The process train utilizes conventional principles of separating liquid from gas in a subsea scrubber, where the liquid is pressurized by a subsea centrifugal pump while the gas is compressed by subsea compressors. The wellstream is cooled by subsea pipe coolers.
Compressors are designed to withstand a certain amount of liquid. For increased confidence of this first-off concept, full quality scrubbers have been included in the system to provide stable and reliable operating conditions. The gas compressors are HOFIM compressors from MAN Diesel Turbo and are set up with reliable magnetic bearings for maximum reliability.
The control system is all-electric, meaning that there is no hydraulics in the system. All valves are operated with electric actuators. Aker Solutions in December 2010 was awarded the contract to deliver the subsea compression system. It took four and a half years from the project’ s start to first gas on September 17, 2015. A close collaboration with Statoil and Aker Solutions’ suppliers was essential to ensure the successful delivery of this break-through technology.
The technology is a major milestone for the subsea industry, opening new opportunities in deeper waters, harsh environments and in areas far from shore. The Åsgard system is designed for large flow rates, built to be reliable, efficient and flexible, and it has operated smoothly from the first installation and during normal operation. The technology recently reached a so-called technology readiness level seven( TRL 7) as the only subsea compression system in the world.
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