Outlet · Gas Plant
Sales Gas Compression
The compressors that raise the processed residue gas back to the pressure of the transmission pipeline.
What it does
After the cold section the residue gas is at much lower pressure than the raw gas. The compression end of the turboexpander recovers part of it, and a booster compressor restores pipeline pressure. Large units are usually centrifugal, often gas turbine driven.
Basics
| Stages | Turboexpander compressor end, then booster compressor |
| Typical type | Centrifugal for high flow |
| Driver | Gas turbine or electric motor |
| Discharge to | Transmission pipeline |
Common failures
- Surge in a centrifugal compressor at low flow
Troubleshooting
- Symptom
- Severe vibration and momentary flow reversal at low rates
- Likely cause
- Flow below the surge limit
- What to check
- Check that the anti surge recycle valve opens before the surge limit