| 摘要 |
PROBLEM TO BE SOLVED: To separate rare gas consisting of krypton and xenon at high recovery percentage, and besides to suppress the condensation of hydrocarbon in an air liquefying separator. SOLUTION: This method of recovering rare gas comprises a process of introducing liquefied oxygen into the first condensing column 6 and taking out condensed liquefied oxygen where rare gas and hydrocarbon are condensed from the bottom of the column and oxygen gas 8 from the head of the column, a process of introducing the above condensed liquefied oxygen 9 into the second condensing column 11 via a decarbonized hydrogen processor 14 and taking out oxygen gas from the head of the column and rare gas liquid 13 from the bottom of the column, and a process of loading a part at least of the oxygen gas from the first condensing column head into the liquefied oxygen phase 4 of the air liquefying separator 1 as circulating liquefied oxygen gas 10. Rare gas is recovered from the liquefied oxygen containing the rare gas taken out of the liquefied oxygen phase 4 in the vicinity of the reboiler capacitor 2 of the air liquefying separator, which is provided with a tray 1c for raising the separation efficiency of the rare gas above the reboiler capacitor 2 besides being the lower part of the upper column of the air liquefying separator 1. |
