The Blake Development Project proves the flexibility of FPSOs in the successful completion of a schedule driven modification to a producing FPSO

Abstract

Abstract The Bleo Holm is an FPSO owned and operated by Bluewater, leased by Talisman for operation of the Ross & Parry Fields located in the North Sea. After discovery of the nearby Blake Field and evaluation of several development concepts a tieback of the Blake field to the Bleo Holm FPSO was selected. In order to be able to produce the Blake field through the Bleo Holm, extensive modifications to the Bleo Holm facility were required that would only be possible to implement during a shutdown period. Without production during the shutdown period the owners of the Ross & Parry Fields would be subject to a loss of oil revenue. Minimisation of the shutdown period was therefore absolutely essential and was reflected in the execution schedule that became the project driver. This paper describes the development of the project during all its phases (concept, engineering, construction and commissioning) and highlights how the construction schedule, being the main driver, influenced decisions taken during the course of the project. The paper also discusses the flexibility of the FPSO concept and the benefits the Blake Field Tie-in to the Bleo Holm provided to the field owners and to Bluewater. Introduction The Bleo Holm FPSO (Floating Production Storage and Offloading Facility) is located in the North Sea 100km North East of Aberdeen in the Moray Firth. The Bleo Holm FPSO is owned and operated by Bluewater and leased to Talisman Energy and partners Nippon Oil, Intrepid and Kerr McGee, for production of the Ross & Parry fields. The field is located in license blocks 13/28a and 13/29a and has estimated recoverable reserves of 50 to 70 million barrels of oil. From sub-sea well completions and flexible risers, well fluids are delivered to the Bleo Holm where, after separation into oil, gas and water, oil is stored in the cargo tanks. The resultant gas is compressed for gas lift and export and the cleaned water is routed overboard. First oil from the Ross & Parry Fields was achieved 19th April 1999. The Blake field, in license blocks 13/24 and 13/29, laying approximately 10 km North from the Bleo Holm location, was discovered in mid 1997. The Blake field, operated by BG Group, is owned by BG Group and partners Paladin and Talisman Energy. The recoverable reserves of the Blake Field were estimated to be approximately 80 million barrels of oil. Initially a dedicated production facility for the Blake Field Development was considered and, following technical, economic and safety evaluations of the various solutions an FPSO concept was selected as the most favourable. As a result of the fall in oil price in 1998 a standalone development was no longer considered economically viable and the concept of a subsea tie-back to a host facility was generated. The following facilities were identified as having the potential.