膜蒸餾塔之實驗研究

Experimental study of membrane-base distillation columns.

詹忻儒(Hsin-Ju Chan)

指導教授 ： 張煖

淡江大學/工學院/化學工程與材料工程學系碩士班/碩士(2015年)

https://doi.org/10.6846/TKU.2015.01070

摘要

依熱力學理論，非絕熱蒸餾塔可有效降低能耗，然而在傳統的板式或填充式塔內進行熱交換具有相當困難度。使用多孔性中纖纖維薄膜作為結構式填充物之蒸餾塔具有高比表面積，氣液相不受流力限制，可方便地提供塔內熱交換功能的優點，即適於做為非絕熱蒸餾塔。本研究利用商業疏水性聚丙烯中空纖維管製作絕熱式與非絕熱中空纖維薄膜模組蒸餾塔，且完成了針對甲醇水溶液之分離實驗，包括精餾與氣提操作模式。本研究也利用一考量熱質傳與塔內壓損之一為嚴謹數學模式，進行模擬分析，模擬氣體與液體出口濃度，相較於實驗值，平均偏差為2.3 %。絕熱塔於精餾與氣提操作模式下，傳輸單元高度(HTU)分別為0.26-0.74 m與0.24-0.62 m。非絕熱塔之塔內熱傳均發生於氣體側，相較於絕熱塔，精餾操作之HTU較低，氣提操作則因熱傳未能發生於液體側，反而使HTU增高。質傳阻力分析顯示主要阻力在液體層，其次為氣體層，薄膜層之阻力則不重要。

關鍵字

中空纖維管 ； 薄膜 ； 填充塔 ； 蒸餾

並列摘要

Bases on thermodynamic theory, diabatic distillation columns can effectively reduce energy consumption. It is difficulty to carry out internal heat exchange in conventional tray or packing towers. Distillation columns using microporous hollow fiber membranes as structured packing provides many advantages, including large specific area, no hydraulic limitations on flow rates and easy internal heat exchange. Hence, it is a good candidate as diabatic columns. In this thesis, experimental and simulation studies of adiabatic and diabatic distillation columns for the separation of water and methanol mixtures are presented. The columns are operated under rectifying and stripping operation modes. For the vapor and liquid outlet concentrations, the average relative deviation of the simulation results from the experimental results is about 2.3%. For the adiabatic column, the height of transfer unit (HTU) of rectifying operation and stripping operation is 0.26-0.74 m and 0.24-0.62 m, respectively. For the diabatic column, the heat exchange is on the vapor side. Compare to adiabatic column, the HTU of diabatic column is lower in rectifying operation, but higher in stripping operation. The major contribution of mass transfer resistance comes from the liquid phase and the membrane layer resistance is not significant.

並列關鍵字

hollow fibers ； membrane ； structural packing ； distillation

參考文獻

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