Patent ID: 8128734
Filing Date: 2012-03-06
Classification: B01D,C01B,Y02C,Y02P

Abstract:
1. An improved method of making enriched oxygen with two-stage pressure-swing adsorption, wherein oxygen and nitrogen are separated from air; the production can be oxygen or nitrogen or both of them; the method adopts two-stage pressure-swing adsorption device operating in series, wherein the first stage pressure-swing adsorption device is used to remove carbon dioxide and water as well as partial nitrogen and enrich nitrogen, and the second stage pressure-swing adsorption device is used to further remove the nitrogen in interim gas which is discharged from the adsorption tower in the adsorption step of the first stage and increase the concentration of oxygen up to the desired level; the adsorption tower of the first stage sequentially undergoes the following steps in one circulation period: adsorption A, purge P′, evacuation VC, the second stage gas backward equalization repressurization 2ER, purge gas repressurization R′, final repressurization FR; the adsorption tower of the second stage sequentially undergoes the following steps in one circulation period: adsorption A, backward equalization depressurization BD′, and final repressurization FR.