PSA process using simultaneous top and bottom evacuation of adsorbent bed

摘要

The present invention relates to the the recovery of low purity oxygen gas from the top of an adsorber vessel into a receiver tank to be used as a purge reflux gas. Recovery of void gas results in improved process efficiency. The invention may also employ a simultaneous evacuation from the top of the adsorber to remove the lower purity void gas while the main waste evacuation step is conducted. This simultaneous co-current top void gas recovery and counter-current waste evacuation from both ends of the adsorber allows for an overall increase in product recovery of between 3-5% over conventional processes. <IMAGE>