Modeling and Simulation of Pressure Equalization Step Between a Packed Bed and an Empty Tank in Pressure Swing Adsorption Cycles

Abstract

Background: It is of paramount importance to pay a great attention when modeling pressure equalization step of pressure swing adsorption cycles for its notable effect on the accurate prediction of the whole cycle performances. Studies devoted to pressure equalization between an adsorption bed and a tank have been lacking in the literature. Many factors could affect the accuracy of the dynamic simulation of pressure equalization between a bed and an empty tank. Methods: The method used for the equilibrium pressure evaluation has a significant impact on simulation results. The exact equilibrium pressure (Peq) obtained when connecting an adsorption column and an empty tank could only be obtained by numerical simulation given the complexity of the set of partial differential equations. Results: It has been shown that, with some simplifying assumptions, one can analytically determine Peq with satisfactory precision. The analytical solution proposed permits to assess rapidly the equilibrium pressure and the equilibrium mole fraction of the adsorbable species in the tank (Yeq) and without the need to resort to a cubersome modeling. Conclusion: Based on the comparisons presented, one can conclude that the agreement between the experimental and numerical results relative to Peq and Yeq is very satisfactory.