Objective
The aim of the GA-SP Project is to develop and test full scale, a subsea processing system that will facilitate economic development of small hydrocarbon reservoirs. The system will include well stram commingling, multiphase separation and pumping, and will be engineered to be suitable for a wide range of reservoir fluid properties, shallow or deep water application, with control from the surface from either a low cost in-field floating platform or from an existing remote fixed installation.
Innovative aspects include :
a) Subsea closed loop modulating control of process parameters.
b) Hybrid diverless maintenance philosophy with vertical retrieval of insert components or complete modules.
c) Single datum alignment of multi-port interconnections.
During the course of this work some significant design modifications were made to the Stage 1 concept, including :
a) Basic module size increased from 3,5 m sq x 5,5 m high to 4 m sq x 6 m high.
b) First stage separator to incorporate oil/water separations, and comprise
3 individual vessels, fabricated from line pipe.
c) Second stage separator vessel to be included in the same module as the first
stage separator.
The main components of the prototype system include :
a) Dummy Production Choke Module (PCM), with a single bay Secondary D
Distribution Module (SDM) incorporating the prototype valved Multibore
Connector (VCM)
b) Separator Module, for 2 stage 3 phase separation, including 4 types of level
detector from 3 manufacturers, and 4 sets of modulating control valves with
hydraulic actuators from 2 manufacturing groups.
c) Ejector skid unit, with 2 alternate ejectors for gas commingling , flow,
pressure and temperature sensors, and (manual) recycle capabilities to the
second stage separator and/or booster pump suction.
d) Power system, comprising 3. 3 kV transformer, switchgear and cable with a sea
water charge pump driven by 500 H. P. 3. 3 kV synchronous motor
. The high
pressure water drives a turbine, coupled to the oil export booster pump.
A modulating control valve bypasses water to control speed of the turbine/
booster pump in response to separator level control.
e) Control and data monitoring system, comprising a topsides process controll
computer, a topsides data logging computer and printer a topsides hydraulic
power unit, a subsea pod for hydraulic fluid distribution and data transmission together with a variety of transducers, cables, connectors and
junction boxes.
The GA-SP Project, which is also supported by a number of oil companies, is being executed in stages. The first stage, Front End Engineering and Preliminary Design, was concerned with outline definition of field scenario concepts and identification of major areas of novelty. This second stage, Detailed Design and Engineering, is concerned with development of a full scale prototype system which incorporates all of the key areas of novelty required to demonstrate the technical feasibility of the concept.
The major tasks of this stage of work have included :
1) Development of Process Flow Diagrams, General Arrangement Drawing and Piping and Instrument Diagrams;
2) Building of Scale Models to show module details and interfaces; 3) Preparation of functional specifications for all equipment, systems, fabrication and assembly requirements;
4) Detailed engineering including hydraulic, mechanical and structural calculations, and preparation of drawings and schedules; 5) Specification of offshore test facility requirements including a conditioning plant to provide a flow of simulated crude oil at 15000 b/d and 35 bar;
6) Development of a computer simulation programme, to be used as a basis for predicting process/control response of the prototype, and subsequently, after correlation with test results, design of commercial systems.
Programme(s)
Topic(s)
Call for proposal
Data not availableFunding Scheme
DEM - Demonstration contractsCoordinator
SW1V 2BL London
United Kingdom