本文旨在評估多種套管熱擴散塔之最佳效率,結果發現:低流率時,捆線塔中兩管反向旋轉之效率最佳;當流率稍為增加時,應僅令捆線塔中一管(熱管或冷管)旋轉即可;惟當流率甚大時,使用空管為宜。
The separation theories of thermal diffusion in various concentric-tube columns, such as open, wired and rotated wired devices, were extended for whole range of concentration and the performances have been compared with different flow-rate range operations. The advantage of the insertion of a wire spiral, having a diameter equal to the annular space, between the two concentric tubes is to reduce the strength of convective flows, resulting in decreased the remixing effect. On the other hand, rotating the tubes in a wired column can either produce the cascading effect, or suppress the strength of natural convection, resulting in enhanced separation efficiency. Under lower follow-rate operation, the wired column with both tubes rotated in opposite directions is recommend to be employed, while under higher flow-rate operation, the wired column with one tube (either hot or cold tube) rotated is preferred to be used. For highest flow-rate operation, all improved columns are not recommended to be employed any more, and in this case the stationary column without a wire spiral is instead to be used.
Relation:
中國化學工程學會會誌 = Journal of the Chinese Institute of Chemical Engineers 38(3-4), pp.281-286