FPSO II - A Second Generation Floating Production System for Offshore Philippines
Authors: Williams Leroy M. , Pierce David M. , Van Berkel Paul 
Published: October 2008

Amoco International selected a floating production system in conjunction with two subsea completed wells for producing the Cadlao Field offshore Palawan Island in the Philippines. This field development scheme designed to accommodate 30,000 barrels of liquid production per day permitted Amoco to produce Cadlao in 18 months after project start and with a minimum of investment cost.

Production from the two wells enters the processing train positioned on the deck of Ai 25,OOO bwt tanker through up to four lines crossing the rigid yoke that connects the tanker to the moored buoy. Two stages of oil, gas and water separation using processing vessels specially designed for 'service in a moving environment segregate the oil, water and gas. Fuel gas is stripped from the produced gas to supply the fuel for powering the tanker boilers. The remaining gas is disposed through a unique designed ground flare system.

Produced water is collected in dedicated tanker storage compartments for final long term settlement prior to disposal overboard. Export quality crude is metered on board the floating production vessel prior to transferring via tandem offloading to the shuttle tanker.

This paper will present the field development logic used in selecting the floating production concept, describe the new engineering designs required for the mooring system, the processing train plus mention the tanker modification work required to transfer an existing trading tanker into an ABS accepted floating production system.

Introduction

On August 25, 1981, oil production began from the Cadlao Field, offshore Palawan Island, Philippines through two subsea completed wells to an integrated floating production, storage, and offloading system, commonly called FPSO. The FPSO installed at the Cadlao Field utilizes a tanker with processing facilities installed on its deck, anchored on site with a rigid yoke mooring system. This system is owned and operated by Terminal Installations Inc. (TIl) under lease to Amoco Philippines Petroleum Company, as operator for a group including Husky (Philippines) Oil Inc., and Balabac Oil Exploration and Drilling Company, Inc.

Prior to discovery of the Cadlao Field the Special Operations Division of Amoco Production Company (International) had conducted a comprehensive study of various offshore production schemes which could be used to develop reservoirs in which reservoir data are uncertain and/or are located in very remote areas. With the discovery of the Cadlao Field in September 1977, a more detailed feasibility study showed that the most cost effective development scheme would be by use of the FPSO system because of several distinct advantages. The use of a FPSO would permit exploitation of a reservoir of unknown size without commitment to costly permanent facilities, the FPSO could be moved to another similar location in the event that production data showed that the reservoir is much larger than anticipated and conventional development is justified or conversely if the reservoir size is limited. An integral consideration to the latter was the fact that the most cost effective system would be one which is leased.