Method and system for refining acrylic acid

The invention provides a method and system for refining acrylic acid, and the method comprises the following steps: mixed gas containing acrylic acid is in countercurrent contact with a crude acrylic acid solution containing acetic acid from the top of a product tower in a light component removal tower, and unliquefied gas rises to the bottom of a washing tower; one part of acetic acid water liquid extracted from the upper part of the washing tower is cooled and then returns to the top of the washing tower, the other part directly returns to the lower section filler of the washing tower, and uncondensed water, acetic acid and other inert gases in the washing tower are sent to a waste gas treatment device or at least part returns to the reaction unit for cyclic utilization; wherein the operating temperature of the top of the washing tower is 55-65 DEG C, and a desalted water supplementing pipeline is arranged on the washing tower; a tower kettle solution of the light component removal tower passes through a pr