| 摘要 |
The objective of the present invention is to provide a method for efficiently producing (meth) acrylic acid by crystallization using a plurality of crystallizer to purify (meth)acrylic acid and a refrigerator for supplying both of a cooling medium and a heating medium, while the refrigerator is stably operated for supplying media having a proper temperature and the temperature of the crystallizers is maintained. The method for producing (meth)acrylic acid according to the present invention is characterized in 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; when both of the crystallization step and the melting step are concurrently carried out in separate crystallizers, from a refrigerator, 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 other crystallizer for carrying out the melting step to melt the (meth) acrylic acid crystal; and when only the crystallization step is carried out before the melting step is carried out, a temperature of a heating medium to be returned to the refrigerator is previously decreased to be lower than a set temperature for the melting step before only the crystallization step is carried out. |
