Acid gas recovery
Also known as: Gas scrubber, Amine unit, Girbotol
Many of the conversion and hydrotreating units generate refinery gas that contains a mix of H2S and CO2, called acid gas. The acid gas recovery units extract the H2S from the other gas components using an amine solvent. Once separated, the H2S can then be sent to the sulfur plant to recover the sulfur.
How it works
The refinery gas is fed into a vessel and mixed with an alkylamine solution. The amine absorbs the acid gas, leaving a clean refinery gas stream that can be sent to the gas plant. The acid-gas-rich amine stream is sent to a regenerator/separation vessel and heated with steam, causing the dissolved acid gas to come out of the solution so it can be drawn off and sent to the sulfur plant.
There are a number of different alkylamine solvents that can be used. The most common are:
- Diethanolamine (DEA)
- Monoethanolamine (MEA)
- Methyl-Diethanolamine (MDEA)
- Diisopropanolamine (DIPA)
- Diglycolamine (DGA)
- Hot potassium carbonate
FIND OUT MORE
The Refinery Reference Desk includes content derived from our industry experts as well as from public data sources such as company websites. Nothing herein is intended to serve as investment advice. This material is based on information that we believe to be reliable and adequately comprehensive, but we do not represent that such information is in all respects accurate or complete. McKinsey Energy Insights does not accept any liability for any losses resulting from use of the content.