Control · Gas Plant
Gas Analyzers
An online gas chromatograph that measures the gas composition, plus moisture and H2S analyzers on the sales line.
What it does
From the composition, the heating value is calculated (GPA 2172 or ISO 6976) and the specific gravity and compressibility (AGA 8), which are needed for energy based custody transfer. Moisture and H2S analyzers confirm the gas meets its sales specification.
Basics
| Heating value | GPA 2172 or ISO 6976 |
| Specific gravity and compressibility | AGA 8 |
| Also on the line | Moisture and H2S analyzers |
| Use | Energy based custody transfer and quality control |
Common failures
- Drifting results because the calibration standard is expired or the sample line is wet
Troubleshooting
- Symptom
- Heating value jumps that the process does not explain
- Likely cause
- Calibration or sample system problem
- What to check
- Check the calibration and the sample system before trusting the reading