Schiehallion
 |
The Schiehallion field was discovered in 1993, some 15 kilometres to the east of the earlier Foinaven Field. |
In April 1996, the UK government gave approval for a combined Schiehallion/Loyal development plan. The Schiehallion field co-venturers comprise: BP, Shell, Amerada Hess, Murphy Petroleum, Statoil and OMV; the Loyal field co-venturers are BP and Shell. Both fields produce to the Schiehallion floating production, storage and offloading (FPSO) vessel, owned on a divided rights basis, hence any available capacity in the vessel is owned separately by the vessel owners, through their interests in the two fields. To assist in any enquiries, BP (as FPSO operator) would be pleased to receive any service request in the first instance.
Development
The water depth at Schiehallion dictates the use of subsea technology and a floating production system. To date, there have been in excess of 42 wells completed in the two fields, in five clusters. Oil and gas is delivered to the FPSO via steel pipelines and flexible risers to the FPSO for processing.
Once on board the FPSO reservoir liquids are separated into oil, gas and water. Oil is evacuated by dedicated shuttle tanker, the Loch Rannoch, which takes the oil to the Sullom Voe terminal in Shetland. Gas is used to power the vessel, with any surplus being piped via the WOSPS (West of Shetland Pipeline System) system to the Sullom Voe terminal to the Magnus oil field where it is re-injected into the Magnus reservoir for enhanced oil recovery. Produced water is cleaned to below 30ppm oil before being re-injected back into the reservoir along with sea water injection.
Production
Schiehallion began production in July 1998 and has achieved peak production rates of around 190 mbd. The Schiehallion FPSO is capable of processing around 200,000 barrels of oil a day and storing
900,000 barrels of oil.
Environment
The Schiehallion and Loyal fields are located in an environmentally sensitive area. Both fields are certified to the international standard for environmental management, ISO 14001, and publish independently verified Environmental Statements annually.
