| 摘要 |
In typically a pressure swing adsorption process for separating a gas mixture such as air, gas vented from adsorbent beds within vessels 10 and 12 during desorption steps of the process is passed into a diffusion vessel 16. Non-permeate gas enriched in nitrogen is returned from the vessel 16 to the vessels 10 and 12 typically with the feed gas. A compressor 72 is employed to raise the non-permeate gas to the feed pressure. Product nitrogen is withdrawn from the vessels 10 and 12 through conduit 100. During each cycle, upon the oxygen concentration reaching a chosen threshold, the nitrogen is diverted from conduit 100 to a diffusion vessel 14. The resulting non-permeate gas enriched in nitrogen is returned to the conduit 100 while the permeate gas may be returned to the adsorption vessels 10 and 12. |
