Abstract: A method of recovering a solvent including: supplying polymerization reactants including one or more monomers and a solvent to a reactor to obtain a polymer solution; supplying a stream including the polymer solution to a separator to separate an upper discharge stream including the solvent, wherein the solvent is in a gaseous phase, and a lower discharge stream including the polymer solution; heating a divergence stream including a part of the lower discharge stream from the separator by a heating device and refluxing the divergence stream to the separator; supplying a residue stream including a remainder of the lower discharge stream from the separator to a steam stripping process unit; and adjusting a vapor mass fraction of the divergence stream which is refluxed to the separator with a pressure adjustment valve after being heated by the heating device.

Abstract: Provided is a method for preparing an acrylic acid including: dehydrating a lactic acid aqueous solution in a reaction unit to prepare a reaction product stream; passing the reaction product stream through a cooling unit and a refining unit sequentially and supplying a discharge stream from the refining unit to an acrylic acid separation column; and separating an unreacted lactic acid as a side discharge stream and separating the acrylic acid as an upper discharge stream in the acrylic acid separation column.

Abstract: Provided is a method for preparing an acrylic acid, in which a lactic acid aqueous solution is dehydrated to prepare a reaction product stream, from which by-products are removed using an extraction column, an extractant recovery column, a first separation column, a second separation column, and a refining column to prepare a high-purity acrylic acid.

Abstract: Provided is a method for preparing an acrylic acid including: supplying a lactic acid aqueous solution to a reactor and performing a dehydration reaction to prepare a reaction product including an acrylic acid; supplying a reactor discharge stream including the reaction product to a first cooling tower and supplying an upper discharge stream from the first cooling tower to a second cooling tower; supplying a first acrylic acid aqueous solution stream discharged from a lower portion of the second cooling tower to an extraction column; supplying an upper discharge stream from the extraction column and a second acrylic acid aqueous solution stream discharged from a lower portion of the first cooling tower to a distillation column; and separating the acrylic acid from a lower discharge stream from the distillation column.

Abstract: A method of recovering a solvent including: supplying polymerization reactants including one or more monomers and a solvent to a reactor to obtain a polymer solution; supplying a stream including the polymer solution to a separator to separate an upper discharge stream including the solvent, wherein the solvent is in a gaseous phase, and a lower discharge stream including the polymer solution; heating a divergence stream including a part of the lower discharge stream from the separator by a heating device and refluxing the divergence stream to the separator; supplying a residue stream including a remainder of the lower discharge stream from the separator to a steam stripping process unit; and adjusting a vapor mass fraction of the divergence stream which is refluxed to the separator with a pressure adjustment valve after being heated by the heating device.