Two-Dimensional Modeling of the Transport Phenomena in the Adsorber During Pressure Swing Adsorption Process

In this study, a two-dimensional model is established to simulate the pressure swing adsorption process. It is the first time a two-dimensional model has been used to study the transport phenomena occurring inside the adsorber during the PSA process with consideration of the heat effect, gas compressibility, radial porosity, and dead volumes. Parts of the results have been compared with the results either from experiments or from the references, which show the model can give a favorable prediction. The 2D simulation results clearly show the concentration distribution and its propagation with time, and concentration maldistribution induced by a nonuniform packing. The velocity, pressure, and temperature distribution is also presented in the paper. A brief discussion of the effect of maldistribution, pressure drop (resistance of porous media) and sorption heat et al. on the concentration distribution is made. As expected, the results visually show that the maldistribution and sorption heat will reduce the adsorber performance. It is also found that a moderate pressure drop is useful for the performance improvement of an adsorber, because it will help bring evenly distributed flow field. There is independent concentration wave velocity, temperature wave velocity, and gas velocity, and during the adsorption step, the concentration wave velocity is larger than that of temperature wave until they coincide with each other. The gas velocity is much larger than the other two velocities. The two-dimensional simulation is found to be very useful for a better understanding of the dynamic sorption and separation process in an adsorber. The results of further research are capable to guide or optimize the design of adsorber configurations.