Experimental and Simulation Studies of an oxygen concentration system using pressure/vacuum swing adsorption technique: system miniaturization and prototype design

The miniaturization of a pressure swing adsorption (PSA) oxygen concentrator is of prime significance for portable applications. This work presented a simplified pressure/vacuum swing adsorption (PVSA) cycle with a concentrator prototype design using a deep evacuation step (-0.82 barg) instead of desorption with purge flow to improve the efficiency of oxygen production process and miniaturize the size of the concentrator. The output of the oxygen concentrator is a 50-90 vol.% enriched oxygen stream in a continuous adsorption and desorption cycle (cycle time = 75-90 s). The size of the adsorption column is 3 cm in diameter and 20 cm in length. A Li+ exchanged 13X zeolite is used as the adsorbent to selectively adsorb nitrogen from air. A dynamic model of pressure and vacuum swing adsorption units was developed to study the pressurization and depressurization process of the adsorption column. The describing equations were solved using COMSOL Multiphysics Chemical Engineering module. The output flow rate and oxygen concentration results from the simulation model were compared with the experimental data. Velocity and concentration profiles were obtained to study the adsorption process and optimize the operational parameters