PROCESS AND PLANT FOR REDUCING CARBON DIOXIDE (CO2) CONTENT FROM A RECYCLE GAS

A process for reducing carbon dioxide (CO2) content from a recycle gas in a plant (100, 200) is provided. The process includes providing an absorption unit (102, 202, 204) that receives a raw synthesis gas comprising the synthesis gas components hydrogen (H2), carbon monoxide (CO), and CO2, and a lean solvent, preferably comprising methanol, and that produces a clean synthesis gas and a laden solvent; providing a flash regeneration unit (104, 208) that flashes the laden solvent received from the absorption unit (102, 202, 204) to generate a recycle gas comprising H2, CO, and CO2 and a partially laden solvent; providing a compressor (106A, 216A) that compresses the recycle gas before directing the recycle gas to the absorption unit (102, 202, 204); integrating a membrane unit (108, 206) between the flash regeneration unit (104, 208) and the compressor (106A, 216A) or between the compressor (106A, 2016A) and the absorption unit (102, 202, 204), wherein the membrane unit (108, 206) comprises a CO2 selective membrane and receives the recycle gas from the flash regeneration unit (104, 208) after flashing; and reducing the CO2 content in the recycle gas by permeating a CO2 rich gas stream through the membrane to a permeate side of the membrane and retaining the recycle gas comprising a H2 and CO rich gas stream on a retentate side of the membrane.