Abstract: A process and apparatus for producing nitrogen by which product nitrogen can be efficiently supplied.

Abstract: The present invention employs a dry-type condenser capable of heat exchange even at small temperature difference for the condensers for the crude argon column, deoxidation column, and pure argon column in an argon separation apparatus using air liquefication and distillation. Additionally, oxygen-enriched liquefied air withdrawn from a plate which is higher than the bottom of the higher pressure column of a double distillation column is employed as the cold source for the condensers. As a result, a large temperature difference between the condensive and vaporative sides of each column's condensers can be obtained. Moreover, even when the total number of theoretical steps of the crude argon column and the deoxidation column exceeds 100, it is not necessary to provide a blower to increase pressure of the crude argon. Thus, the cost of the apparatus and its operation can be reduced.