Abstract: The invention is a pressure swing adsorption system. The pressure swing adsorption system has a plurality of primary adsorbent beds and at least one secondary adsorbent bed. The feed gas stream is flowed to a primary adsorbent bed loaded with an adsorbent that will preferentially adsorb certain components in the feed gas. Non-preferentially adsorbed components flow from the adsorbent bed during this time. Upon saturation of the adsorbent with the adsorbed components, the flow of feed gas is ceased. The adsorbent is fully loaded with the preferentially adsorbed component and there is feed gas in the void space between the adsorbent particles. This primary adsorbent bed undergoes regeneration by partial depressurization through the secondary adsorbent bed followed by a complete depressurization to a final lower pressure. There can be two or more primary adsorbent beds and there will be at least one secondary adsorbent bed.