| 摘要 |
<p>A method of recovering an oxigen-rich gas from a gaseous mixture mainly comprising nitrogen and oxygen by pressure swing adsorption using two adsorption towers (A and B) packed with adsorbents adsorbing selectively nitrogen, wherein the recovery of the oxygen-rich gas remaining as the result of pressure equalization between the two towers is conducted exhaustively and nitrogen is continously withdrawn by suction by connecting a vacuum pump (8) to either tower (A) or tower (B) without interruption. To that end, the pressure equalization between the two towers (A and B) is conducted in at least two steps in such a manner that one tower (A or B) is increased in pressure, while the other tower (B or A) is decreased in pressure, so that the oxygen-rich gas can be recovered till the pressure difference between two towers (A and B) decreases to almost zero.</p> |
