| 摘要 |
<p>The material to be cooled is fed across or falls through a current of cooling gas. The gas pref. flows in a closed circuit, and pref. at least part of the gas which has been heated by the material is filtered. The heated gas may be cooled by a liquefied gas before being recycled to mix with newly evaporated gas. Cooling is pref. carried out by spraying the warm gas with liquefied gas.</p> |
