Centralized Production Facilities
Authors: Rench S.D. , Folse K.A. , Johnson C.M. , Chan J.H-C. 
Published: October 2008

This paper describes the development of the central Production Platform located in Green canyon Block 52. Same of its unique features are discussed along with the platform schedule and key management decisions which impacted the design, construction, and installation of the platform.

INTRODUCTION

The central Production Platform (CPP) is a major component of the Jolliet and Marquette Pr0jects which develop oil and gas reserves in the Green canyon area of the Gulf of Mexico (GCM). The CPP is located in Green canyon Block 52 (GC-52). It is installed in 616 feet of water and is connected via pipelines to the Tension Leg Well Platform (TLWP). It is bridge connected to the Marquette platform. Space has been allocated on CPP for future (as yet unapproved) developments within the Green canyon area. As the name implies, the CPP serves as a central production platform where oil, gas, and produced water are brought from outlaying platforms. There are no wells on the CPP. oil and gas are treated andconditioned to meet their respective pipeline specifications. produced water is treated, and oil is removed to enable its disposal overboard. Produced water may be used ultimately for reservoir pressure maintenance. Having these processing facilities at a central location allows space, weight and :manpower to be minimized at the outlying platforms.

An overview of the schedule for the CPP is as follows: Conceptual Engineering occurred in January -June, 1987. Detailed Engineering took fourteen (14) months (June, 1987-August, 1988). Fabrication began on the jacket in April, 1988 and on the deck/facilities in July, 1988 with Sail Away on the jacket in April. 1989 am on the deck in August, 1989. Offshore hookup and commissioningoccurred from September-November, 1989.

Additional information on the Jolliet Project and the CPP is presented in papers entitled "Jolliet-The Project";1 ''Materials, welding and Fabrication for the Jolliet Project";2 and "Jolliet Deepwater Pipelines."3

JACKET

The jacket is largely of conventional design with a few unique features. It is installed in a water depth of 616 feet, with a weight in air of 8260 tons. The jacket is a four-leg design with two skirt piles per corner and no main piles. Total pile penetration is 340 feet with a total weight of all eight piles of 2250 short tons.

The jacket was built with eight J-tubes for pipelines. Four pipelines have currently been pulled into the J-tubes with four J-tubes reserved for future pipelines. Other jacket appurtenancesinclude four personnel mini-boat landings, four barge bumpers, eight pipe caissons and two skim piles.

Perhaps the most unusual jacket feature is the half depth launch box. The launch box is a square cross-sectional steel tubular frame fromjacket elevation -132 feet down to jacket elevation -616 feet. The launch box was designed to take the weight and stresses of the entire jacket during load out, transport, and launch. The half depth launch box and the main jacket frame are notrigidly connected, thus allowing them to react to thermal and other environmental stresses somewhat independently.