| 摘要 |
<p>PURPOSE:To adsorb and remove impurities in an raw material to be refined to refine the raw material by cooling an adsorption tower packed with an adsorbent, and passing the low boiling point raw material through the adsorption tower. CONSTITUTION:Liquefied nitrogen is flushed into the closed space A between the adsorption tower 10 and a vessel 6 to gasify the liquefied nitrogen. Consequently, the atmosphere in the closed space A is cooled by the heat of vaporization to a temp. (-208 deg.C) lower than the temp. of the liquefied nitrogen, and the atmosphere in the closed space A is used as the cold source for cooling the adsorption tower 10 and the raw material. The impurities in the raw material (e.g., helium) is filtered off by a separator 7, and the raw material is then introduced into the adsorption tower 10 arranged in the vessel 6 and contg. an adsorbent such as activated carbon and a molecular sieve. Meanwhile, the impurities (e.g., air) separated by the separator 7 is discharged to the outside of the system by a conduit 9 via a heat exchanger 5.</p> |
