It will be developed as a subsea production facility with onshore processing, meaning that there will be no need for a permanent offshore platform structure to be in place at the Corrib field during the operation phase.
The type of subsea facilities used for the Corrib development are used on many other subsea developments around the world. It is an exciting technology that involves a large number of specialist companies to design, build and install.
The Corrib project is made up of four parts: the offshore operations including the wells and subsea facilities, the offshore section of pipeline, the onshore section of pipeline and finally the gas processing plant at Bellanaboy Bridge, County Mayo.
Corrib gas is trapped in a gas reservoir 3,000 metres below the seabed by a layer of impermeable rock. The gas is extracted by drilling wells into the reservoir. To date five wells have been drilled and made ready for production at a later date.
All the offshore equipment for Corrib is placed on the seabed in a water depth of about 350 metres. As the water is too deep for manned diving, installation is carried out using under water robots known as “remotely operated vehicles” or ROVs.
The offshore pipeline is made up of more than 7,000 sections of pipe that were welded together onboard the Solitaire pipelay vessel during the summer of 2009. The pipes were laid on the seabed from the landfall at Glengad approximately 83 kilometres out to the Corrib field. The 8.3km onshore section of pipeline will run from Glengad to the terminal and will include a 4.9km section under Sruwaddacon Bay.
Once it comes ashore, the gas will be processed or dried at the terminal at Bellanaboy by removing liquids so that it is suitable to flow into the Bord Gáis Eireann pipeline network.