Gas separating system

Abstract

A gas generator which separates a gas such as oxygen from a gas mixture such as air using a sorbent process. A sorbent contained in a fixed cooled bed absorbs the gas from the mixture; simultaneously a second bed of sorbent which previously absorbed the gas is heated and the gas is thereby desorbed from the sorbent. After a given time, the functions of the beds are exchanged. Heating and cooling of the two sorbent beds is accomplished by means of coolant which passes through each bed. Immediately after the functions of the beds are switched, the cool coolant first flows through and cools the absorbing bed, then is valved to a pump and to the heater for heating and then is valved to heat the second sorbent bed before being valved to a cooler for cooling. A set time thereafter, but before the functions of the beds are again switched, coolant from the absorbing bed is valved directly to coolant return, and coolant from the heater is valved to the desorbing bed and therefrom back to the pump and heater in a closed loop to conserve heat transferred to the coolant by the heater. Such heat would otherwise be lost when the coolant is cooled upon being valved to the cooler. The set time is selected so that when the temperature of the coolant exiting from the absorbing bed equals the temperature of the coolant exiting from the desorbing bed, the closed heating loop is instituted.