US Patent 7413595 Control scheme for hybrid PSA/TSA systems

An improved control scheme is set forth for an adsorption process that removes water and carbon dioxide (CO2) from a feed gas using a hybrid of both temperature swing (i.e. TSA) and pressure swing (PSA) to regenerate the adsorbent. The control scheme comprises adjusting the quantity of heat to be provided by the regeneration gas as a function of temperature data taken within a strategic portion of the water selective adsorbent zone. The strategic portion corresponds to the location for the desired transition from regeneration by temperature swing, to regeneration by pressure swing. In a preferred embodiment of the present invention, said quantity of regeneration heat is also adjusted as a function of the water content of the feed gas.