초록

Process and single-bed pressure swing adsorption system for separating gas mixtures, especially air. The process includes a simultaneous countercurrent product purge and partial product repressurization step which shortens cycle time and improves overall system operation.

대표청구항 ▼

[ What is claimed is:] [1.] A pressure swing adsorption process for the separation of a pressurized feed gas containing at least one more strongly adsorbable component and at least one less strongly adsorbable component which comprises the steps of:(a) introducing the pressurized feed gas at a feed

[ What is claimed is:] [1.] A pressure swing adsorption process for the separation of a pressurized feed gas containing at least one more strongly adsorbable component and at least one less strongly adsorbable component which comprises the steps of:(a) introducing the pressurized feed gas at a feed pressure into a feed end of a single adsorber vessel containing a solid adsorbent which preferentially adsorbs the more strongly adsorbable component, withdrawing from a product end of the adsorber vessel an adsorber effluent gas enriched in the less strongly adsorbable component, and introducing a portion of the adsorber effluent gas into a gas storage tank;(b) terminating introduction of the pressurized feed gas into the adsorber vessel and depressurizing the adsorber vessel by withdrawing gas from one end of the adsorber vessel until the pressure therein reaches a minimum adsorber pressure;(c) continuing to withdraw gas from the one end of the adsorber vessel by evacuation while simultaneously introducing stored adsorber effluent gas from the gas storage tank into the other end of the adsorber vessel such that the pressure in the adsorber vessel remains essentially constant at the minimum adsorber pressure;(d) repressurizing the adsorber vessel from the minimum adsorber pressure to the feed pressure by introducing one or more repressurization gases into the adsorber vessel, wherein at least a portion of the repressurizing is effected in a combined repressurization-purge step in which gas is evacuated from the one end of the adsorber vessel while stored adsorber effluent gas from the storage tank is introduced into the other end of the adsorber vessel such that the pressure in the adsorber vessel increases to a value intermediate the minimum adsorber pressure and the feed pressure; and(e) repeating steps (a) through (d) in a cyclic manner.