Rectification system and method for improving UV value of ethylene glycol product

The invention belongs to the technical field of coal ethylene glycol rectification, and particularly relates to a rectification system and method for improving the UV value of an ethylene glycol product, the rectification system comprises a methanol recovery tower, a dehydration tower, a dealcoholization tower, a product tower, an ethylene glycol recovery tower and the like, alkali liquor and desalted water are added into a tower kettle of the dehydration tower, and the desalted water is added into the top of the dealcoholization tower; part of aldehyde, ketone, acid, ester and other impurities in tower bottoms of the dehydrating tower are subjected to chemical reaction with water and alkali liquor to be removed, and ketone and ester are further subjected to chemical reaction with water in the dealcoholization tower to be removed, so that the content of aldehyde, ketone, acid, ester and other impurities in ethylene glycol products extracted from the product tower and the ethylene glycol recovery tower is redu