Simulation of pressure swing adsorption modules having laminated structure

A mathematical model was formulated for the bulk separation of binary gas mixtures in micro-structured pressure swing adsorption (PSA) modules consisting of parallel channels lined with adsorbent. Axial and radial dispersion in the gas phase and mass transfer resistance in the adsorbent phase were taken into consideration. The partial differential equations governing the concentration profiles in the gas and adsorbent phases were solved by orthogonal collocation. The model enabled the prediction of the concentration profiles in both the gas and adsorbent phases (as a function of location and time), the product purity and the separation efficiency. The effects of model parameters and operating conditions on the module performance were investigated. Simulation of oxygen enrichment from air by molecular sieve 13X indicated that long modules with thin layers of adsorbent, narrow gas flow channel heights and large numbers of flow channels give the best separation.