| 摘要 |
<p>PROBLEM An object of the present invention is to provide a crystallization unit capable of producing a purified acrylic acid having high purity efficiently. SOLUTION The present invention provides a crystallization unit to separate an acrylic acid-containing solution into a mother liquid and a purified acrylic acid, wherein the crystallization unit comprises a crystallizer having an exit to take out the mother liquid and the purified acrylic acid alternately; a supply line to supply the acrylic acid-containing solution to the crystallizer; and a recovery line to recover the mother liquid and the purified acrylic acid alternately from the crystallizer which is connected to the exit, and wherein the recovery line is equipped with an opening and closing unit consisting of a ball valve or a gate valve.</p> |
