Offshore Compressors World's First Subsea Gas Compression Systems Operate in the North Sea
The world's first subsea gas compression system went on stream recently at the Statoil-operated Åsgard field. Aker Solutions has delivered the subsea compression system for this field development.
Norway – “We are immensely proud to be part of this achievement, which is a major milestone for our industry,“ said Chief Executive Officer, Aker Solutions, Luis Araujo. "The close collaboration we have had with Statoil and our suppliers has been essential to ensure the successful delivery of this break-through technology."
Aker Solutions in December 2010 was awarded the contract by Statoil to deliver the system, which consists of modules for two identical sets of compressors, pumps, scrubbers and coolers fitted together in an 1,800-metric ton steel frame. These components were delivered to Statoil and were ready for installation on the seafloor of the Åsgard field in the Norwegian Sea.
This subsea technology milestone opens new opportunities in deeper waters, and in areas far from shore, oilfield operator Staoil believes: “This is one of the most demanding technology projects aimed at improving oil recovery. We are very proud today that we together with our partners and suppliers have realised this project that we started ten years ago,” says Margareth Øvrum, Statoil’s executive vice president for Technology, Drilling and Projects.
Recovery from the Midgard reservoir on Åsgard will increase from 67 percent to 87 percent, and from 59 percent to 84 percent from the Mikkel reservoir. Overall, 306 million barrels of oil equivalent will be added.
Demanding Technology Development
As a field gets older, the natural pressure in the reservoir drops. In order to recover more oil and gas, and get this to the platform, compression is required. The closer to the well compression takes place, the more oil and gas can be recovered.
Traditionally compression plants are installed on platforms or onshore, but this plant is located in 300 metres of water. Due to the challenging location, quality in all parts of the project has been essential, and will help ensure high regularity, maximum recovery and robust production.
The project started in 2005, and the plan for development and operation (PDO) was approved in 2012. An estimated eleven million man-hours have been spent from the start until completion. More than 40 new technologies have been developed and employed after prior testing and verification. Some of this work has taken place at Statoil’s Kårstø laboratory in Western Norway.