METHOD FOR PRODUCING NITROGEN GAS, METHOD FOR SEPARATING GAS AND DEVICE FOR PRODUCING NITROGEN GAS

摘要

A method for producing nitrogen gas from raw materials using a PSA method is characterized in that, using a second adsorbent charged in an auxiliary adsorption tank provided in line to connect two main adsorption tanks charged with a first adsorbent, the oxygen concentration in recovery gas drawn from the main adsorption tank operating under depressurization equalization is reduced, and said gas is conducted to the main adsorption tank operating under pressurization equalization.