以中空纖維薄膜蒸餾模組於去鹽製程：建模與最適化設計

Desalination through Hollow Fiber Membrane Distillation Module: Modeling and Optimal Design

吳秉鍾(Ping-Chung Wu)

指導教授 ： 陳榮輝

中原大學/工學院/化學工程研究所/碩士(2007年)

https://doi.org/10.6840/cycu200700804

摘要

薄膜蒸餾是比較新的分離技術，優點在於其操作簡單、佔地空間小、安全又節能。因應近年全球暖化造成淡水資源的短缺，我們希望能利用薄膜蒸餾的技術來獲得更多的淡水資源。

薄膜蒸餾是利用一疏水性薄膜將兩不同溫度之溶液隔開，兩溶液因受到溫度差的影響，在薄膜表面形成一蒸氣壓差，此蒸氣壓差推動著高溫溶液氣體分子往低溫端移動。因此薄膜兩側的蒸氣壓差可視為薄膜蒸餾之驅動力。

本文探討以薄膜蒸餾結合中空纖維管組件為系統來做模擬，希望在了解各可變參數造成的影響後，能針對節能效果與產量的提昇做一組件之設計。在了解薄膜質傳機制後，利用動量傳送、質量傳送與能量傳送之探討，分別針對直接接觸式薄膜蒸餾（Direct-Contact Membrane Distillation）與氣隙式薄膜蒸餾（Air Gap Membrane Distillation）建立可描述系統內部溫度、濃度、流速與壓力隨著管長位置變化之關係式。並針對如何提昇膜組件之產量與節能效果提出一最適化設計。

關鍵字

最適化設計 ； 建模 ； 中空纖維管 ； 薄膜蒸餾

並列摘要

Membrane distillation is a novel separation technology and has the advantage of being easy to operate, small-scaled, safe and high energy efficient. Global warming has reduced the supply of fresh water and we hope to use membrane distillation as a source to obtain fresh water.

In membrane distillation, a hydrophobic membrane separate two mixtures of different temperature. The difference in temperature of the mixture will cause the formation of vapor pressure gradient on the surface of the membrane which causes the gas particle of the higher temperature mixture to move to the lower temperature end. Thus, the steam pressure difference at the two sides of the membrane is considered the driving force of membrane distillation.

In this work, the combination of membrane distillation with hollow fiber tube as a system is simulated, with the aim to understand the effect of various parameters on the system and conduct equipment design to increase efficiency and productivity. After understanding the transport phenomena, through investigation of the momentum, heat and mass transfer, the models for Direct-Contact Membrane Distillation and Air Gap Membrane Distillation which describe the internal temperature, concentration, flow rate and pressure a long the length of the tube is developed and optimization design method to increase efficiency and productivity is also proposed.

並列關鍵字

Optimal design ； Modeling ； Membrane distillation ； Hollow fiber

參考文獻

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