| 摘要 |
This invention provides a pressure fluctuation adsorption method that, in recovering gases having a high added value such as xenon and krypton contained in exhaust gas, discharged, for example, from semiconductor manufacturing apparatuses, at high concentration with high recovery, can provide a novel PSA process which can simultaneously concentrate easy-adsorption components such as xenon and difficult-adsorption components such as nitrogen to a high concentration. In the pressure fluctuation adsorption method, a separator is used, comprising lower and upper cylinders packed with an adsorbent, a raw material gas storage tank for storing a raw material gas to be introduced into the lower cylinder, an easy-adsorption component storage tank for storing a main component which can easily be adsorbed on the adsorbent, and a compressor, and the easy-adsorption component, which can easily be adsorbed on the adsorbent, and the difficult-adsorption component, which is difficult to be adsorbed on the adsorbent, are recovered. The pressure fluctuation adsorption method is characterized by successively repeating (a) adsorption step, (b) rinsing step, (c) lower cylinder pressure reduction step, (d) upper cylinder pressure reduction step, and (e) purging step based on a predetermined sequence. |
