Patent ID: 6500235
Filing Date: 2002-12-31
Classification: B01D,C01B,Y02C

Abstract:
A duplex pressure swing adsorption process for purifying a product gas from a feed gas stream in a system having at least first and second pressure swing adsorption stages for selectively adsorbing/desorbing one or more of impurity gases from the feed gas stream containing product gas, each stage having an upper bed and a lower bed in fluid communication with each other and each bed of each stage containing one or more adsorbents for adsorption of one or more impurity gases, the process comprising:providing the feed gas stream to the first pressure swing adsorption stage and adsorbing one or more of the impurity gases from the feed gas stream and collecting purified product gas as effluent from the upper bed of the stage, desorbing one or more impurity gases from adsorbent(s) in the second pressure swing adsorption stage to provide a recyclable stream containing the desorbed gas(es), recycling at least a portion of the recyclable stream from the second stage to the lower bed of the first adsorption stage and adsorbing in the lower bed one or more impurity gases from the recyclable stream thereby providing a purified recyclable stream as effluent from the lower bed to the upper bed of the first stage.