Anne K. Rhodes
Refining/Petrochemical Editor
Characteristics of crude oil from the important North Sea Forties stream have been updated (see OGJ, June 6, 1983, p. 75).
Forties oil field went on production in September 1975, operated by BP Exploration Co. Ltd. Since then, six other U.K. fields and Norway's Heimdal field have been tied into the system.
Fields currently included in the stream are Forties; South, Central, and North Brae; Balmoral; Montrose/Arbroath; Buchan; and Heimdal.
Distillation data for the Forties stream are in Table 1.
Production in the Forties field peaked in 1978-81 at 500,000 b/d. By 1983, it had dropped to 447,000 b/d, and by March 1987, to about 400,000 b/d. Current production is about 200,000 b/d.
The original pipeline was laid in 1973-74 from the Forties field in Block 21/10 of the North Sea's U.K. sector to the Cruden Bay terminal near Peterhead, Scotland.
The pipeline was 32-in. in diameter-the largest offshore pipeline that could be laid at the time. Peak flow through the line was 565,000 b/d in January 1989.
A new 36-in. line was laid in 1990, and throughput is now about 440,000 b/d (OGJ, May 6, p. 49). In 1983, BP sold stakes in Forties oil field and reduced its interest from 94.7783% to 83.123%.
The Forties system was joined by Brae in the summer of 1983. Montrose field, on production since 1976, was linked to Forties by Amoco U.K. Exploration Co. by a 29-mile, 14-in. pipeline in 1984.
In March 1987, production from SE Forties began at 2,000 b/d, connected by a 2.5-mile, 12-in. pipeline. The unmanned platform is controlled from Forties Alpha platform.
In 1989, BP started installing gas-lift equipment. This is expected to raise recovery to 2.47 billion bbl.
Marathon Oil U.K. started up a subsea production system at Central Brae in 1990. In 1992, production from Miller oil field will be moved through the Forties system, with liquids from the Bruce gas-condensate field entering in 1993.
[SEE BOOK FOR STATISTICS]
Copyright 1991 Oil & Gas Journal. All Rights Reserved.
