Gas compression uptime, performance and throughput usually becomes more critical as an offshore asset matures.
Gas platforms in particular have increased compression duty requirements as depletion occurs.
Oil platforms that utilise gas lift become totally reliant on gas compression for achieving target production figures.
Gas compression uptime and throughput directly correlate with oil production volumes. Oil platforms with declining gas profiles are challenging with the gas compression system having to operate at low throughputs, particularly on start-up when high gas lift pressures are required.
Therefore, efficient and stable compression systems are the cornerstone of achieving good production and low flaring figures for all assets. Compression and gas turbine systems are usually the most complex systems on an offshore installation.
Core has extensive experience in improving the operation of gas compression systems in the UK and overseas. Typical problems addressed include:
- Compressors surging during instability, startup or during shutdown/rundown. A fast trend of a compressor surge is shown below.
- Compressor instability on single and multistage compressors due to overly aggressive or overly complicated compressor OEM control software designs.
- Conservative setup of compression control systems by OEM vendors due to warranty obligation concerns.
- Gas compression capacity and loadshare controls being too complicated and operated in manual as a result.
- Inefficient operation due to antisurge control valves being operated partially open with excessive recycling and capacity/energy efficiency losses.
Core can assist any client achieve improved operation of their gas compression systems and this can take one of many forms:-
- Design/peer reviews prior to installation.
- Review of vendor or OEM design/software designs.
- Factory Acceptance Test attendance.
- Startup and commissioning.
- Surge, performance testing and loadsharing system setup.
- Compressor mapping, fouling calculations and debottleneck/re-wheel studies.