Subsea multipurpose field development solution has been chosen for the field development scenario of the Brenda and Nicol Fields in the UKCS, operated by OILEXCO North Sea Ltd.
This paper presents an overview of the Brenda and Nicol fields, the system solutions and flexibility selected for the field development and in brief the selection process. The Framo Single pump Station (FSS) forms the basis for a system solution, which is built around the compact MultiManifold for tie-in of individual satellite wells, the multiphase pump for boosting of the unprocessed well streams, the multiphase meter for reservoir management and individual well testing and the control modules for pump station and production system control.
The Brenda Field is located in UKCS Block 15/25b (License P1042) and UKCS Block 15/25e (License P1157), both owned by OILEXCO North Sea Limited (100%). The field is located approximately 220 km north east of Aberdeen in the U.K. Sector of the Central North Sea, see Figure 1. The field will be developed via a subsea tie back of 4 horizontal wells to the CNR International (UK) Limited operated Balmoral Floating Production Vessel (‘FPV’), 8,5 kilometers to the North East. First oil is scheduled for Q4 2006.
The Nicol field located in UKCS Block 15/25a is owned by OILEXCO North Sea Ltd., ConocoPhillips and ENI. The field with one production well will be tied back to the Brenda subsea production manifold. See figure 2.
The system comprises a subsea production manifold based on the Framo Single pump Station (FSS), see Figure 3. For the Brenda field, the FSS will be arranged to route five wells to topside from day one. Four wells are located near by the FSS while one is a satellite well located approximately 10 km from the production manifold. The manifold arrangement has a possibility of eight wells to be routed through the FSS, which gives a spare capacity for three future well tie-ins.
The design provides the possibility to apply gas lift on each of the wells. The gas lift flow rate will be based on a choke setting due to VenturiMeter readings. Pressure and temperature transmitters are installed near the VenturiMeter to improve the accuracy of the readings. ROV operated isolation valves for each gas lift system are provided. Gas lift will mainly be used to kick of the wells and to enable production at high water cuts.
Each production well will be routed to a Multiport Selector Manifold (MSM) located on the manifold. The MSM gives the opportunity to route one well at a time through a test line with a Multiphase Flow Meter (MPFM) and a sand detector installed. The MPFM hence allows for individual well testing. A production choke and diver/ROV operated isolation valve is provided for each well on the manifold.