Purification system for air separation system

The invention relates to a purification system for an air separation system. The purification system comprises a pretreatment device and a purifier, wherein the pretreatment device comprises an air filter, an air compressor, a regenerator, a cooler and a precooler which are sequentially arranged in the air flowing direction; the air compressor comprises a first-level compressor, a first-level cooling device, a second-level compressor, a second-level cooling device and a third-level compressor which are sequentially arranged in the air flowing direction; the precooler comprises an air cooling tower used for carrying air and a water cooling tower used for feeding cold water into the air cooling tower to conduct heat exchange; the purifier is used for receiving the air output by the pretreatment device and comprises two adsorption cylinders, heaters and a purifier controller; and the two adsorption cylinders are arranged in parallel and internally provided with filter elements, the heaters are arranged outside the corresponding adsorption cylinders, and the purifier controller is used for controlling connection and disconnection of the adsorption cylinders and the heaters.