In case of sudden power failure during the operation of small air separation unit, the following steps should be followed:
First, open the vent valve (anti surge valve) of air compressor to prevent the air compressor from surging and causing the air compressor to reverse due to air backflow;
Then check whether the molecular sieve adsorber switch should be interlocked to close, if not, it should be manually closed, and record the program status of molecular sieve adsorber before power failure. Expander, refrigerator, air precooling system and argon purification system shall also be shut down by interlocking, if not, manually;
Finally, stop the delivery of oxygen and nitrogen products, stop the output of liquid oxygen, liquid nitrogen and liquid argon, and close the water valve of air precooling system and external connection.