Method and apparatus for concentrating chlorine gas
AssigneeMitsui Toatsu Chemicals, Inc.
InventorsYoshitsugu Kono, Masaaki Ura, Hiroyuki Itoh, Satoshi Tsuruda
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Abstract
A method and an apparatus for concentrating/purifying a chlorine gas are disclosed in which a pressure swing adsorption method for alternately repeating an adsorbing operation and a desorbing operation employing one or more adsorption towers packed with an adsorbent for adsorbing the chlorine gas are used to obtain a high-purity concentrated/purified chlorine gas and an exhaust gas containing virtually no chlorine gas is obtained from the chlorine gas containing impurities by terminating the adsorption operation when the rate of temperature rise near the outlet end of an adsorption tower due to adsorption of chlorine therein rises above a predetermined amount.
Claims18
A method for concentrating/purifying a feed chlorine gas containing impurities in a pressure swing adsorption-desorption system in which, in an adsorbing operation, the feed chlorine gas is fed to an adsorption tower packed with an adsorbent which adsorbs the chlorine gas, to produce an exhaust gas depleted of chlorine which is discharged from the tower, and in a subsequent desorbing operation, the chlorine gas adsorbed by the adsorbent in the tower is desorbed at a reduced pressure, whereby the feed chlorine gas is concentrated/purified and is then discharged from the tower in the desorbing operation and the regenerated adsorption tower is then used again in an adsorbing operation, which method comprises introducing the exhaust gas discharged from the adsorption tower during the adsorbing operation into a second adsorbing tower for carrying out the adsorbing operation, whereby the adsorbing operation is conducted sequentially in at least two steps in at least two adsorption towers, thereby producing a chlorine-free exhaust gas.
An apparatus for concentrating/purifying a feed chlorine gas containing gaseous impurities in a pressure swing adsorption system comprising a plurality of adsorption towers into which in an adsorbing operation the feed chlorine gas is fed to a plurality of adsorption towers packed with an adsorbent adapted for adsorbing the chlorine gas, thereby producing an exhaust gas depleted in chlorine gas, and from which, in a desorbing operation, the adsorbent is desorbed therefrom, thereby concentrating/purifying the feed chlorine gas to a high purity;
- connecting means for feeding during an adsorption operation the exhaust gas depleted in chlorine gas discharged from one of the plurality of adsorption towers to another of the adsorption towers, whereby the adsorbing operation occurs in at least two stages in at least two adsorption towers and the chlorine gas concentration in the exhaust gas discharged from the apparatus is reduced to substantially zero.
Dependencies are inferred from the claim text.