METHOD OF RECOVERING ENRICHED GASEOUS OXYGEN

摘要

A process is provided for recovering oxygen-rich gas by enriching gaseous oxygen contained in crude gas by a single-tank PSA process which utilizes a single adsorption tower (1) loaded with an adsorbent. In the process, a cycle is repeated which includes an adsorption step of introducing crude gas into the adsorption tower (1), a desorbing step of desorbing unnecessary components from the adsorbent, a washing step of introducing washing gas into the adsorption tower (1) for discharging the remaining gas from the adsorption tower (1) , and a pressurizing step of raising the internal pressure of the adsorption tower (1). The desorbing step includes recovering semi-enriched oxygen gas existing in the adsorption tower (1) after finishing of the adsorption for retention in a recovery tank (3). The washing step includes introducing part of the semi-enriched oxygen gas existing in the recovery tank (3) into the adsorption tower (1) as the washing gas. The pressurizing step includes introducing the rest of the semi-enriched oxygen gas retained in the recovery tank (3) into the adsorption tower (1).