Project Phase
Concept Select
Disciplines
Study Management
Multidiscipline Topsides
Multidiscipline Subsea
Estimation
Location
UKCS
Service
Engineering Consultancy
Summary
Infinity rapidly established a viable tie-back to an existing FPSO concept by evaluating the system holistically across subsea, pipelines, flow assurance and topsides facilities to define a workable development pathway for the project’s challenging fluids. This provided the operator with clear design drivers, risks and requirements for progressing into the next phase with confidence.
Overview
Infinity were selected to carry out a Concept Select study by a UKCS operator that was assessing a development of a satellite field via a subsea tie-back to an existing FPSO. The selected concept comprised up to two gas-lifted producers, with control and chemical services routed via existing umbilical infrastructure—introducing important constraints that needed to be understood early.
Objective
Establish a clear, technically robust basis for concept selection by defining:
- Subsea architecture and pipeline system configuration
- Required brownfield topsides modifications on the host facility
- Flow assurance and operability risks (and practical mitigations)
- A preliminary CAPEX basis and key considerations to progress into the next phase
km subsea tie-back
Gas Lift Wells
Viable Concept Selected
Key findings
- Recommended layout: 10” wet-insulated production line with 4” gas-lift line tied back via a production manifold and tie-in skid.
- Identified existing umbilical capacity as a constraint for chemical injection and control distribution.
- Identified host facility modifications required across gas lift, chemicals, metering and process handling.
- Brownfield constraints highlighted the need for early operations alignment to avoid late rework and execution delay.
- Wax deposition risk identified due to low predicted arrival temperatures
- Mitigation options defined, including pipe-in-pipe for improved thermal performance or a continuous wax-inhibition strategy, subject to umbilical limits.
Differentiator
We applied a whole-system, end-to-end approach from first principles, assessing subsea architecture, pipeline configuration, flow assurance and brownfield topsides constraints simultaneously. By integrating flow assurance, process and subsea considerations from the outset, we avoided siloed optimisation and defined a concept that was technically robust, operable and achievable within existing host/umbilical limitations.
Outcome
The study delivered a viable development pathway that balanced thermal performance, chemical delivery constraints, brownfield topsides limitations and pipeline configuration. This gave the operator client a clear view of the key design drivers, technical risks and requirements needed to progress into the next phase with confidence.
Find Out More
Have questions about this project? Contact us to find out how Infinity can help to manage your subsea assets.
joao.conde@infinity-limited.com
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