Project Phase
Concept Select
Disciplines
Process Led Topsides Multidiscipline
Location
UKCS
Service
Engineering Consultancy
Summary
We supported an operator’s decision-gate concept select for a mature offshore facility by identifying low-pressure production bottlenecks, defining a phased brownfield modification scope, and demonstrating how sustained low-pressure operation could be achieved without compromising safety or asset integrity.
Overview
A mature offshore asset was approaching a phase where declining reservoir pressure would require progressively lower inlet operating pressures to maximise recovery. We were engaged to complete a feasibility assessment and concept study to confirm whether the existing topsides processing facilities could support low-pressure production over time, and to define the minimum modifications needed to enable the transition while maintaining continuous production.
Our integrated multi-discipline team assessed process feasibility, equipment integrity, layout constraints, safety and execution considerations together, ensuring recommendations were proportionate, deliverable and aligned with remaining asset life.
Objective
- Assess feasibility of future low-pressure operation across the topsides process train
- Identify bottlenecks and limitations in key process and utility systems
- Define the minimum brownfield modifications required to enable low-pressure production
- Provide a robust technical basis to support the operator’s decision gate and next-phase planning
Phased Strategy
Modifications Identified
Decision Gate Ready Study
Key findings
- No fundamental barriers were identified to enabling low-pressure production across the main process systems, including fuel gas, dehydration and produced-water handling.
- Export compression capability was confirmed for nearer-term low-pressure operation, with a defined approach for staged upgrades as pressures reduce later in field life.
- Required modifications were targeted and limited to a small number of genuine constraints, centered on export compression, selected high-temperature pipework, control valve performance and low-pressure flare capacity.
- A phased modification strategy was developed that aligns investment with forecast production needs, avoiding premature capital spend while preserving long-term operability.
- Design pressure/temperature limits and safeguarding constraints were identified early, enabling focused resolution in FEED rather than late-stage rework.
Differentiator
We applied a system-level, asset-aware brownfield mindset, treating the facility as a live operating installation rather than a greenfield design case. By combining production forecasting with process simulation and integrity checks, we avoided over conservatism while maintaining compliance with operator technical and safety standards, resulting in recommendations that were proportionate, executable and aligned with remaining asset life.
Outcome
We delivered a decision-gate-ready concept study that gave the operator confidence low-pressure production is achievable within the existing facility envelope, supported by a focused and cost effective modification scope targeting only true constraints. The work also provided a robust foundation for FEED planning, cost estimating and long lead item identification, demonstrating our ability to unlock late-life asset value through pragmatic, multi-discipline concept development grounded in operating data and execution realism.
Find Out More
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joao.conde@infinity-limited.com
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