Treating · Gas Plant
Amine Contactor
A tall tower where sour gas flows up through trays or packing against a lean amine solution flowing down, which absorbs the hydrogen sulphide and carbon dioxide.
What it does
Sweetens the gas so it meets the sales specification and is safe to handle. The amine is chosen by the gas: MEA and DEA remove both acid gases, while MDEA is selective for H2S when CO2 should stay in the gas.
Basics
| Common amines | MEA, DEA, MDEA |
| MDEA strength | Up to about 60 wt% in water |
| Selective for H2S | MDEA |
| Out of the bottom | Rich amine to the regenerator |
Common failures
- Foaming that carries amine out with the treated gas
Troubleshooting
- Symptom
- Rising differential pressure across the tower and off spec gas
- Likely cause
- Foaming from hydrocarbons, solids or degradation products
- What to check
- Check the inlet separation and filtration, and dose antifoam as a short term fix