Process for removing oxygen from mixed gas streams using a swing adiabatic absorption-isothermal desorption cycle

Claim 1

A process for removing oxygen from an inert gas stream containing oxygen by adiabatic absorption of the oxygen on a dioxygen absorbent and isothermal desorption of the oxygen during dioxygen absorbent regeneration wherein the process is designed to operate below the temperature of decomposition of the absorbent comprising the steps of: (a) introducing an oxygen-containing inert gas stream into a first bed of a dioxygen absorbent at a temperature chosen on an isotherm of the particular dioxygen absorbent so as to allow adiabatic absorption to proceed without reaching the temperature of degradation of said absorbent; (b) adiabatically absorbing essentially all of the oxygen content of said inert gas stream on said dioxygen absorbent, while removing an essentially oxygen-free inert gas from said bed; (c) terminating said absorption on said first bed before oxygen therethrough in said bed; (d) switching the flow of the inert gas stream to a second dioxygen absorbent bed for adiabatic absorption of the oxygen content of said stream, while removing an essentially oxygen-free inert gas from said bed; (e) desorbing said first bed isothermally by supplying a high temperature heat exchange fluid to said bed to drive absorbed oxygen off said dioxygen absorbent; (f) cooling said first bed to the initial absorbent temperature; (g) representing said first bed with essentially pure oxygen-free inert gas from the downstream flow of product gas from said second bed; (h) terminating said absorption on said second bed before oxygen breakthrough in said bed; (i) switching the flow of the inert gas stream back to the first bed, while desorbing the second bed as described in step (e) above; (j) cooling said second bed to the initial absorbent temperature; (k) repressurizing the second bed with essentially pure oxygen-free inert gas from the downstream flow of product gas from said first bed; (1) cyclically repeating steps (a) through (k) for the production of an essentially oxygen-free inert gas.