SEPARATION RECOVERY METHOD AND SEPARATION RECOVERY DEVICE FOR CARBON DIOXIDE

PROBLEM TO BE SOLVED: To provide a method and a device suitable for efficiently recovering carbon dioxide, when carbon dioxide is liquefaction-recovered from a gaseous raw material including carbon dioxide and impurities, even in the case the carbon dioxide concentration in the gaseous raw material varies.SOLUTION: Provided is a carbon dioxide separation recovery device X1 for separately recovering carbon dioxide, regarding a gaseous raw material including carbon dioxide and impurities, in the conditions where the carbon dioxide concentration in the gaseous raw material varies, comprising: a liquefaction recovery apparatus 5 where carbon dioxide is liquefaction-recovered from the gaseous raw material under low temperature high pressure to exhaust off gas; and a PSA gas separation apparatus 6 where the carbon dioxide included in the off gas can be concentratedly separated by a PSA method, and gas separation is performed in such a manner that the treatment of the gas separation is changed based on at least either state of the gaseous raw material or the off gas.SELECTED DRAWING: Figure 1 【課題】二酸化炭素および不純物を含む原料ガスから二酸化炭素を液化回収する際、原料ガスにおける二酸化炭素濃度が変動する場合においても高い回収率で効率よく回収するのに適した方法および装置を提供する。【解決手段】本発明の二酸化炭素分離回収装置Ｘ１は、二酸化炭素および不純物を含む原料ガスについて、当該原料ガスにおける二酸化炭素濃度が変動する状況において二酸化炭素を分離回収するための装置であって、低温高圧下で上記原料ガスから二酸化炭素を液化回収し、オフガスを排出する液化回収装置５と、上記オフガスに含まれる二酸化炭素をＰＳＡ法により濃縮分離可能であり、上記原料ガスおよび上記オフガスの少なくとも一方の状態に基づきガス分離の処理を変更させてガス分離を行う、ＰＳＡガス分離装置６と、を備える。【選択図】図１