(255f) Gas Separation Cycles Using Multiple Adsorption Units

Adsorption technology has produced very useful separation units that are widely used in industrial practice. Some of the better known separations include Pressure Swing Adsorption (PSA) and Temperature Swing Adsorption (TSA). In the quest to expanding the usefulness of adsorption separations, cycles have been produced that look at the adsorption process in a different way. These include the "inverted PSA" process and several processes that tend to improve the separation of the most adsorbable component at higher levels of purity. As the need of separate components with higher levels of purity increases, the option of using multiple adsorption units becomes an important option. These options are illustrated for cases such as hydrogen recycle in Solid Oxide Fuel Cell cycles and the concentration of oxygen from very low levels to high purities for special applications.