Patent ID: 9359203
Filing Date: 2016-06-07
CPC Classification: B01D,C01B

Claim Text:
1. A method for producing nitrogen gas from a raw material gas using a PSA system, the method comprising: using a second adsorbent, which is packed in an auxiliary adsorption tank provided in a line connecting two main adsorption tanks packed with a first adsorbent and has a faster oxygen adsorption rate than the first adsorbent, to reduce an oxygen concentration within a gas discharged from a main adsorption tank performing a depressurization equalization step, and then introducing the gas into a main adsorption tank performing a pressurization equalization step, wherein the line connecting the two main adsorption tanks is a line connecting either upstream sides of each of the main adsorption tanks, or an intermediate section of one main adsorption tank and an upstream side of the other main adsorption tank.