HELSINKI, Finland -- Wärtsilä is supplying inert gas systems for the new FSU under construction for the Statoil-operated Heidrun oil and gas field in the Norwegian Sea, and for two associated shuttle tankers.
Statoil (OSE:STL; NYSE:STO) will own the FSU, with Singapore-based petroleum transportation company AET Tanker owning the tankers. All three vessels are being built by Samsung Heavy Industries in South Korea. Wärtsilä is due to deliver its equipment to Samsung in October.
For offshore applications the nitrogen generators are engineered to allow for larger capacities.
Inert gas generator systems are used to prevent the gas mixture in cargo tanks or bunkers from reaching a range where explosions could occur.
Inert gas maintains the oxygen content of the tank atmosphere below 8%, making the air and hydrocarbon gas mixture in the tank too lean to ignite. This can be critical during discharge operations when more hydrocarbon vapor is likely to be present in the atmosphere, and the same applies to the tankers during the ballast voyage.
Additionally, inert gas can be used to purge the tank of volatile components in readiness for gas freeing, i.e. replacing the gas mixture with air. Nitrogen generators are then used to supply dry air and oil-free inert gas for purging, pressurizing, and blanketing.
The new FSU should serve on Heidrun through at least 2045. It will export the oil from the field and will be connected to a buoy, with crude oil loaded onto the FSU via a subsea pipeline and underwater hoses. Wärtsilä is also supplying the FSU with deep well pumps and fire water packages.