Simulation of a Fractionated Vacuum Swing Adsorption Process for Air Separation

A fractionated vacuum swing adsorption process previously proposed in the literature that simultaneously produces a 98% nitrogen-enriched gas and a 90% oxygen-enriched gas from ambient air is studied by simulation. This process utilizes CaX zeolite as the major adsorbent and alumina as the desiccant packed at the feed air end. In the isothermal simulation the feed air is considered to be a ternary mixture of nitrogen, oxygen, and water vapor, and the dynamic behavior of the adsorption bed and the effects of air humidity are studied.