Cryogenic double-tower nitrogen making equipment

The utility model discloses cryogenic double-tower nitrogen-making equipment which comprises an oxygen-extracting rectifying tower, a nitrogen-making rectifying tower, a plate heat exchanger, a molecular sieve purifier, a liquid nitrogen storage tank and a controller, the nitrogen-making rectifying tower comprises an upper tower and a lower tower, and an oxygen-enriched liquid air eduction tube of the upper tower is communicated with the oxygen-extracting rectifying tower; a first regenerated gas eduction tube of the upper tower is converged and communicated with a second regenerated gas eduction tube of the oxygen-lifting rectifying tower and then is connected with a molecular sieve purifier through a plate heat exchanger; an oxygen-enriched waste gas eduction tube of the oxygen-lifting rectifying tower is connected with the plate heat exchanger; an output check valve, and a regenerated gas output regulating valve, an oxygen content analysis sensor and a regenerated gas output flow sensor which are electrica