在氣相或液相添加低表面張力溶劑對氣─液接觸裝置之相間質傳影響

The Effect on the Interfacial Mass Transfer of a Gas-Liquid Contact Device by Adding a Low Surface Tension Solvent into the Gas or Liquid Phase

楊乃璇(Nai-Hsuan Yang)

指導教授 ： 鍾財王

中原大學/工學院/化學工程學系/碩士(2007年)

https://doi.org/10.6840/cycu200700531

摘要

在吸收式除濕系統之工作溶液氯化鋰表面添加低表面張力之揮發性有機溶劑時，能夠使得界面有局部表面張力梯度的形成，因而使表面流體產生擾動現象，稱為Forced Marangoni convection。當此現象發生時，可增加界面的擾動程度，並對氣－液間質傳性能具有決定性的影響，因此，Marangoni effect可以促進表面更新，並帶動液面周圍的空氣，增加氣－液接觸的機會，進而促使質傳性能有所提升。
本實驗將針對上述之原理，於小型之氣─液接觸裝置，分別探討低表面張力之揮發性有機溶液添加於液相及氣相時，對界面擾動及除濕效率的影響。系統操作參數包括入口溼度、氯化鋰溶液濃度等。本實驗將比較在不同的操作條件之下，未添加乙醇與乙醇分別存在於液相與氣相時，對系統對除濕效率差異的比較，並對其質傳現象加以探討。

關鍵字

質傳係數 ； 氣相與液相添加 ； Marangoni ； 表面張力 ； 吸收 ； LiCl

並列摘要

Adding a low surface tension volatile organic solvent into the surface of working solution of lithium chloride in a dehumidification system, the surface tension gradient will be occurred in the gas-liquid interface and formed the interfacial turbulence, which is called the force Marangoni convention. When the system has this phenomenon, it will increase the degree of interfacial turbulence and dominate the mass transfer performance between the gas-liquid interface.
This theory will be applied in a gas-liquid contact device to find the effect of interfacial turbulence and dehumidification efficiency by adding a low surface tension solvent into the gas or liquid phase. The operating parameters include inlet humidity, lithium chloride concentration, etc. The experiments will find out the differences of the dehumidification efficiency in different conditions of with adding alcohols in gas or liquid phases and without adding alcohols.

並列關鍵字

Absorption ； LiCl ； Surface tension ； Mass transfer coefficient ； Gas and liquid phase ； Marangoni

參考文獻

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