| 摘要 |
<p>Provided is a method for removing impurities from carbon dioxide gas, which comprises: a step in which crude carbon dioxide gas containing high-boiling-point impurities and low-boiling-point impurities is fed to a liquid carbon dioxide purification column, a predetermined amount of the fed crude carbon dioxide gas is introduced to the column top, and the liquid carbon dioxide containing the high-boiling-point impurities is discharged from the liquid carbon dioxide purification column base to outside the system, thereby removing the high-boiling-point impurities contained in the crude carbon dioxide gas; and a step in which the carbon dioxide gas discharged from the column top is split into a first and a second carbon dioxide gas current, the first carbon dioxide gas current is introduced to a liquefier at the purification column top in order to fully condense the current to liquid carbon dioxide, and the liquid carbon dioxide is introduced to a vapor-liquid separator at the purification column top while the second carbon dioxide gas current is mixed therewith in order to separate the low-boiling-point impurities contained in the liquid carbon dioxide by reflashing in the vapor-liquid separator at the purification column top.</p> |
