Nitrogen supply system

According to the nitrogen supply system, liquid nitrogen prepared by a nitrogen making unit is stored in a liquid nitrogen storage tank, and nitrogen prepared by the nitrogen making unit is stored in a storage buffer container. When the nitrogen making unit is normal, the storage buffer container receives the nitrogen gasified by the nitrogen making unit and the gasifier, and the amount of the nitrogen output in unit time is increased so as to meet the nitrogen supply requirement. When the nitrogen making unit breaks down, the liquid nitrogen pump can continuously extract liquid nitrogen from the liquid nitrogen storage tank and convey the liquid nitrogen to the gasifier for gasification so as to obtain nitrogen, the nitrogen enters the storage buffer container, a large amount of nitrogen originally stored in the storage buffer container is matched, and the nitrogen flows to the nitrogen using end from an output port, used for being communicated with the nitrogen using end, of the storage buffer container. An