Patent ID: 8637701

Claim:
A method for producing (meth)acrylic acid, comprising the steps of at least crystallizing (meth)acrylic acid and melting the (meth)acrylic acid crystal obtained in the crystallization step; wherein: two or more crystallizers are employed; (1) when the crystallization step and the melting step are concurrently carried out in separate crystallizers, a cooling medium is supplied to a crystallizer for carrying out the crystallization step to crystallize (meth)acrylic acid and a heating medium is supplied to the other crystallizer for carrying out the melting step to melt the (meth)acrylic acid crystal from a refrigerator; and (2) when the crystallization step is carried out before the melting step is carried out, the temperature of a heating medium to be returned to the refrigerator is decreased to be lower than a set temperature for the melting step before the crystallization step is carried out.