Management of the purification system in the normal operation of the nitrogen generator: When the air separation unit is in normal operation, the switching procedure will be automatic. At this point the operator should pay attention to:

(1) When the molecular sieve adsorber is running, it is necessary to regularly monitor the molecular sieve temperature curve and the content of carbon dioxide at the outlet to judge whether the work of the adsorber is normal.

(2) It is necessary to closely monitor the switching procedure of the adsorber and whether the switching pressure difference is normal. In case of failure, it should be dealt with in time.

(3) Pay close attention to the normal operation of the refrigerator. In the event of a short-term failure, causing the air outlet temperature to rise, the switching cycle of the adsorber should be shortened in time, and the failure should be eliminated in time.

(4) When boosting the pressure of the air compressor, it should be carried out slowly to prevent the air velocity from being too large. When charging a low temperature system, or adding load to the system (starting the expander, opening the throttle valve, etc.), do so slowly to prevent system pressure fluctuations.

(5) When the air separation plant is stopped, the main air valve behind the adsorber and each switching valve of the purification system should be closed immediately, so as to prevent the airflow velocity from being too large and impacting the molecular sieve bed when it is restarted. An important aspect of the management of molecular sieve adsorbers is the management of "switching devices". The purifier needs to be checked once a week to see if the specified temperature is reached during regeneration and cooling, and whether the switching time meets the regulations. If there is any abnormality, it should be adjusted. After the adsorber has been used for two years, the particle breakage of the molecular sieve should be determined. If necessary, take out all the sieves to remove particles, and be sure to carefully blow through the sieve to remove the particles and powders deposited on it. To add or replace molecular sieves as required, unidentified molecular sieves must not be used, and it is necessary to ensure that the adsorption layer reaches the specified thickness.