| 摘要 |
A process for producing high purity carbon monoxide (CO) by membrane purification of CO produced in a solid oxide electrolysis cell (SOEC) comprises the steps of generating a gaseous mixture of CO and CO2 by SOEC electrolysis of CO2, applying a moderate pressure on the retentate side of the membrane in one or more membrane units connected to the exit of the SOEC via a compressor or an ejector, applying a lower pressure than the moderate pressure on the permeate side of the membrane, splitting the retentate stream, which is now enriched in CO, into two separate parts, expanding the first part of the retentate stream to reach the permeate low pressure conditions, leading the above-mentioned part of the retentate to the permeate side of the membrane to lower the partial pressure of CO2 on this side, and recycling the outlet permeate stream back to the SOEC as a feed gas together with fresh CO2. Preferably the membrane unit is designed with a tubular membrane or multiple planar membranes connected in series, and the retentate and permeate streams are operated in counter-current mode. |
