NGL · Gas Plant
Fractionation Train
A series of distillation towers that split the NGL mix into ethane, propane, butane and natural gasoline, one product off the top of each tower.
What it does
Columns run in sequence and each takes its lightest component overhead: ethane first, then propane, then butanes, leaving natural gasoline (pentanes plus) as the last bottom product. Each product must meet tight purity specifications.
Basics
| Towers | Deethanizer, depropanizer, debutanizer |
| Products | Ethane, propane, butanes, natural gasoline |
| Sequence | Lightest component taken overhead in each column |
| Purity | Set by tight product specifications |
Common failures
- Off spec product when a column is not separating as designed
Troubleshooting
- Symptom
- Product analysis out of specification
- Likely cause
- Column operating away from its design conditions
- What to check
- Compare the analyzer results with the column conditions and correct them