Albacora Field FPS: Another Deepwater Development Offshore Brazil

Abstract

Abstract The Albacora field, one of the huge deepwater fields at Campos Basin, has been on stream since 1987 with a step phased development strategy, using early production systems. Undergoing phase I1 will use two floating production units, a semi-submersible and a FPSO, each one capable to process 100,000 bopd. This paper presents the Albacora deepwater field case study, stressing the evolution of the field development evaluation studies and highlighting the project milestones, as the Petrobras 25 FPS conversion, the diverless manifold design and installation, the rig allocation strategy and the well completion and tie in techniques, describing also the world record breaking subsea well ESP installation to be performed in 1,100 m water depth, among others. Introduction The Albacora complex is located 107 km off Rio de Janeiro State coast, in the northeastern part of Campos Basin, being discovered in 1984 at 293 m water depth. Appraisal wells in the following three years had confirmed the field extension into deeper water depths. It covers an area of nearly 235 km2 and can be divided in two distinct fields, Albacora and East Albacora, as oil properties and reservoir characteristics vary significantly (Fig. 1). Recoverable reserves of the Albacora field are 665 million barrels of 26 to 29' API oil and 13.5 billion std m3 of gas in water depths varying from 230 to 1,000 m, while the East Albacora field shows 41 5 million barrels of 15 to 20' API oil in water depths ranging from 1,000 to 2,000 m. A total of eight different oil reservoirs are found in the Albacora complex from Tertiary (Oligocene, Eocene and Miocene) and Cretaceous (Albian) sandstone layers. Phased Field Development While developing production technology with an aggressive R&D program aiming to reach the 1,000 m water depth target, the plan was to bring on stream the shallower portion, at that time considered to be deep, of the Albacora field through a pilot system. Clarifying geological, reservoir and production uncertainties, and also generating early cash1 flow to support the next steps were the main goals. The pilot system, consisting of six wells connected to a diver assisted manifold producing to a FPSO and a monobuoy, started production in 1987 and it is known as Albacora Phase I. The six wells were completed with lay away christmas trees in water depths ranging from 252 to 419 m. The FPSO was moored at 230 m water depth, being rigidly connected through a yoke to the monobuoy, exporting the production with a shuttle tanker tied to a second monobuoy. Peak production achieved 18,000 bopd and 0.25 million std m3/day of gas.