| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for removing impurities, whereby solid matter or a component can be removed from the interior of a distillation column when a target matter is being isolated from a mixture gas containing solid matter or a component capable of forming solid matter by polymerization during the distillation in the distillation column.SOLUTION: The method comprises: supplying a mixed gas containing as an impurity, either the solid matter or a component capable of forming the solid matter by polymerization to below a first filling layer 12 and from the exterior of a distillation tower 11 to the interior; distilling and extracting a gas that contains a target matter from a first discharge line 14 to the exterior of the distillation column 11; extracting a liquid that contains the impurity from a second discharge line 15 to the exterior of the distillation column 11; supplying at least some of the extracted liquid to the first filling layer 12 from above as a circulated liquid; rinsing away the impurity captured in the first filling layer 12 by using the circulated liquid as well as a reflux liquid from the top of the distillation column 11; and extracting the liquid that contains the impurity through the second discharge line 15 to the exterior of the distillation column 11 in order to remove the impurity from the interior of the distillation column 11. |
