摘要 |
A method for producing nitrogen gas from a raw material gas using a PSA system, the method including 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, to reduce the oxygen concentration within a recovered gas discharged from the main adsorption tank performing a depressurization equalization step, and then introducing the gas into the main adsorption tank performing a pressurization equalization step. |