This paper describes the development of CABGOC's Kuito field offshore Angola using an FPSO and subsea facilities. This field development marks the start of deepwater production off Angola, and is in addition particularly significant in view of the extremely short project duration from contract award to start of production. This was achieved while incorporating the highest international environmental standards, including the re-injection of produced gas.
The Kuito field, which has an average water depth of 400 metres, lies in Block 14 offshore Cabinda. Block 14 covers some 1.5 million acres, with water depths ranging from 200 to 1,500 metres. CABGOC, as operator of Block 14, have also announced discovery of three other fields in the same block. Apart from CABGOC's 31% share as operator, Agip, Total and Sonangol have 20% shares each, and Petrogal has the remaining 9%.
The Kuito field was discovered in April 1997, and first oil was produced in December 1999.
The field development plan divides the development into two main Phases, 1 and 2, with Phase 1 itself being divided into Phases 1A, 1B and 1C.
Phase 1A is the first production phase of the field development, with surface production facilities consisting of a spread moored FPSO based on a converted VLCC tanker. The subsea facilities consist of 12 production wells produced via a subsea manifold, which is located at a distance of 1.9 statute miles from the FPSO. The manifold is tied back to the FPSO via two production lines, each with a diameter of 11", a test line with a diameter of 6", and associated gas lift and control umbilicals. Associated gas is used as fuel on the FPSO, and for gas lift of the production wells, with any unused amounts being re-injected, such that under normal operations there is no flaring.
Stabilised crude is pumped to export tankers via a CALM buoy offloading system. The CALM buoy is located 1.15 statute miles from the FPSO and connected to the FPSO via two flexible flowlines, which each have an internal diameter of 15". A schematic of the Phase 1A field layout is shown in Figure 1.
Phase 1B covers Water Injection facilities, with seawater treatment and pumps already provided on the FPSO, and a 10" flowline and control umbilical leading to an 8-slot manifold.
Phase 1C will consist of an additional subsea production centre, similar to the 1A arrangement.
Design life for the FPSO is 10 years, with all other field facilities and FPSO mooring system having a design life of 25 years.
As of January 2000, Phase 1A is producing through 7 wells, with the remaining trees in the course of being installed and hooked up. Phase 1B is in the course of development with the start of operations set for second quarter 2000, and Phase 1C is at the engineering and evaluation stage.
Consortium Arrangement
