| 摘要 |
<p>PURPOSE:To attain to reduce cost, in a method for removing impurities in gas, by arranging a getter material reactive with impurities and having high temp. dependence or the soaking part of a heating furnace and arranging a getter material low in temp. dependence to the non-uniform part thereof while flowing gas in this order. CONSTITUTION:Impure gas entering a reaction tube 5 through a gas introducing pipe 6 is reacted with the getter material A of the uniformly heating part 11 of a heating furnace 1. The getter material A is inexpensive but high in temp. dependence and the concn. of the impure gas is lowered in the lower part of the getter material and low concn. impurities-containing gas flowed out. However, the non-uniform part in the downstream side of said reaction tube 5 is packed witha getter material B and, because this getter material B is low in temp. dependence, the low concn. impurities-containing gas can be treated even at a non- uniform temp. By this method, the concn. of impurities in gas is lowered and the use amount of the expensive getter material B is reduced.</p> |
