Method of continuous recovery of (meth)acrylic acid and apparatus for the method

An apparatus for continuous recovery of (meth)acrylic acid, comprising

• a acrylic acid absorption tower equipped with a mixed gas inlet to which a mixed gas comprising (meth)acrylic acid, organic by-products, and water vapor, produced by a synthesis reaction of (meth)acrylic acid, is fed, in which a low concentration (meth)acrylic acid aqueous solution outlet, at which a low concentration (meth)acrylic acid aqueous solution obtained by contact of the mixed gas with water is discharged, is installed at any one point corresponding to 30 to 70% from the highest part, and a high concentration (meth)acrylic acid aqueous solution outlet is installed at the lowest stage;
• a (meth)acrylic acid extraction tower equipped with an aqueous solution inlet that is connected with the low concentration (meth)acrylic acid aqueous solution outlet of the absorption tower through an aqueous solution transfer line, an extract outlet at which a (meth)acrylic acid extract obtained by contact of the introduced (meth)acrylic acid aqueous solution with an extraction solvent is discharged, and a raffinate outlet at which the raffinate is discharged;
• a solvent separation tower equipped with an extract inlet that is connected with the extract outlet of the extraction tower through an extract transfer line, an upper stage outlet at which the solvent obtained by heating the introduced extract is discharged, and a lower stage outlet at which the feed excluding the solvent recovered from the extract is discharged;
• and
• a water separation tower equipped with a feed inlet that is connected with the lower stage outlet of the solvent separation tower through a transfer line, and is connected with the high concentration (meth)acrylic acid aqueous solution outlet of the (meth)acrylic acid absorption tower through a transfer line, and a (meth)acrylic acid outlet at which acrylic acid obtained by the distillation of the introduced feed is discharged,
• wherein the apparatus is operated such that a weight ratio of the extraction solvent to water in the low concentration (meth)acrylic acid aqueous solution fed to the (meth)acrylic acid extraction tower is 2.7 or more,
• wherein the low concentration (meth)acrylic acid aqueous solution has 50 wt % or less of (meth)acrylic acid, and the high concentration (meth)acrylic acid aqueous solution has 50 wt % or more of (meth)acrylic acid.