氣隔式薄膜蒸餾(air gap membrane distillation)原理乃是利用薄膜兩側的飽和蒸汽壓差為驅動力促使水蒸氣通過薄膜及其氣隔層後，在冷凝板上冷凝，進而達到分離的效果，然而，當薄膜蒸餾發生所謂的溫度極化現象時，其對於系統產能會有相當顯著的影響，此現象越明顯則產能相對低落。
    本研究針對氣隔式薄膜蒸餾之主要設備進行效率改善的研究，目的為：(1)設計新型紊流促進因子(Eddy promoter)，以有效的改善系統內部之溫度極化現象進而提升系統產能，並歸納出一新型納賽數經驗公式，描述紊流促進因子對於通道內部熱對流效應的影響；(2)藉由一維數學模型針對薄膜蒸餾設備的熱量與質量傳送機制進行研究，配合實驗分析以驗證經驗公式與數學模型的正確性，並探討在不同之設計參數及操作條件對於薄膜蒸餾系統之流體溫度分佈、溫度極化現象、純水透膜通量增加百分率與水力損耗提升百分率的影響。
    研究結果顯示，平板型氣隔式薄膜蒸餾系統之理論值與實驗值的相對誤差總平均為8.84 %，而新型紊流促進因子能夠有效的提升系統透膜通量，在本研究設定的操作條件之中，最高可達到約10%的增益。

The air gap membrane distillation (AGMD) device is a membrane distillation (MD) operation for which air gap between the membrane and the condensation surface in contact with the cold stream.  The existence of temperature gradient in a AGMD system means that the membrane surface temperatures always contact with bulk temperatures.  Attempts to reduce the effect of temperature polarization were made implementing eddy promoters to improve the flow characteristic.  A new design of the parallel-plate AGMD device using roughened-surface flow channel for heat transfer enhancement was proposed to increase the pure water productivity in saline water desalination.  The purposes of this study are (1) to develop the heat-transfer coefficient correlation for the roughened-surface channel; (2) to develop a one-dimensional mathematical model and propose a general numerical method for predicting pure water productivity of membrane distillation systems; (3) to study the effect of temperature polarization on the pure water productivity improvement.  The correlated equation of estimating heat-transfer coefficient for the eddy promoter by using roughened-surface flow channel was obtained, and the results show that the agreement between the experimental results and the theoretical predictions are fairly good.

目錄
中文摘要	I
英文摘要	II
目錄	III
圖目錄	VI
表目錄	X
第一章 緒論	1
1-1 引言            1
1-2 薄膜蒸餾系統簡介  4
1-3 研究動機與方向    7
第二章 文獻回顧	9
2-1 薄膜蒸餾         9
2-2 紊流促進因子     14
第三章 理論分析	17
3-1氣隔式薄膜蒸餾之熱量、質量傳送機制分析              17
3-1-1 氣隔式薄膜蒸餾質傳機制之理論分析	        20
3-1-2 氣隔式薄膜蒸餾熱傳機制之理論分析	        27
3-1-3 溫度極化現象                                	33
3-2新型紊流促進因子納賽數經驗公式之建立       36
3-2-1 納賽數經驗公式模型	                        37
3-2-2 實驗數據之取得與分析計算流程	                40
3-3 平板型氣隔式薄膜蒸餾系統一維理論模型之建立 43
3-3-1 平板型薄膜蒸餾系統一維理論模型	                44
3-3-2 理論數據取得與計算分析流程-朗吉庫塔數值解析方法	47
3-3-3 系統水力損耗                                51
3-4 數學模擬參數之設定                     53
第四章 實驗分析	55
4-1 平板型氣隔式薄膜蒸餾系統                55
4-2 鋁板表面粗糙化流程與量測方式             62
4-3 實驗步驟                             66  
第五章 結果與討論	67
5-1 新型紊流促進因子之納賽數經驗公式迴歸分析   67
5-2 平板型氣隔式薄膜蒸餾系統                71
5-2-1 系統操作變因對於透膜通量之影響	               71
5-2-2 溫度分佈與溫度極化現象                       72
5-3 添加紊流促進因子之平板型氣隔式薄膜蒸餾系統 82
5-3-1 紊流促進因子對於透膜通量之影響	               82
5-3-2 溫度分佈與溫度極化現象                       84
5-4 設計參數於透膜通量與水力損耗之影響       94
5-4-1 透膜通量增益程度與水力損耗提升程度	       95
5-4-2 透膜通量與水力損耗提升程度之比較	       97
第六章 結論	103
6-1 新型紊流促進因子之納賽數經驗公式         103
6-2 平板型氣隔式薄膜蒸餾系統                104
6-3 添加紊流促進因子之平板型氣隔式薄膜蒸餾系統 104
6-4 模組設計參數於透膜通量與水力損耗之影響     104
符號說明	        106
參考文獻         	113
附錄一 經驗公式迴歸數據	   120
附錄二 理論計算下之數據表	   120
附錄三 碳纖維之遮蔽面積	   132 

圖目錄
圖1-1海水淡化成本	        3
圖1-2 薄膜蒸餾之操作型態	5
圖1-3 薄膜蒸餾之模組型式	6
圖1-4 研究架構圖	        8
圖3-1 薄膜蒸餾系統熱量及質量傳送機制示意圖     18
圖3-2 薄膜蒸餾於薄膜內部之質量傳送阻力模式	23
圖3-3 氣隔式薄膜蒸餾之質量傳送阻力示意圖	26
圖3-4 氣隔式薄膜蒸餾之熱量傳送阻力串聯模式	27
圖3-5 薄膜蒸餾於薄膜內部熱量傳送之阻力模式	28
圖3-6 溫度極化示意圖	33
圖3-7 溫度極化現象改善示意圖	36
圖3-8 熱對流係數運算流程圖	42
圖3-9 順流操作之平板型氣隔式薄膜蒸餾系統示意圖	45
圖3-10 朗吉庫塔法求聯立方程組之計算示意圖	49
圖3-11 氣隔式薄膜蒸餾系統運算流程圖         	50
圖4-1 平板型氣隔式薄膜蒸餾系統簡圖	        56
圖4-2 平板型氣隔式薄膜蒸餾系統實驗設備圖(a)側視圖(b)正視圖 56
圖4-3 平板型氣隔式薄膜蒸餾模組分解圖	                  58
圖4-4 壓克力頂板鑲入(a)光滑面、(b)粗糙面鋁板之實際圖	  59
圖4-5 網狀尼龍纖支撐層(a)示意圖(b)實際圖	          60
圖4-6 碳纖維支撐層實際圖(a)上視圖(b)下視圖	          61
圖4-7 表面粗化工法與量測示意圖	                  63
圖4-8 表面粗糙化之鋁板實際圖	                          64
圖4-9 表面粗糙化之鋁板於光學顯微鏡下(a) Plate1、(b) Plate2、(c) Plate3	                                          64
圖5-1-1 納賽數比值與通道表面相對粗糙度關係	        70
圖5-1-2 納賽數理論值與實驗值比較圖	                70
圖5-2-1 冷流層固定25℃進口溫度且熱流層流體為純水下，不同操作參數對於透膜通量之影響                                        75
圖5-2-2 冷流層固定25℃進口溫度且熱流層流體為鹽水下，不同操作參數對於透膜通量之影響	                                75
圖5-2-3 冷流層固定15℃進口溫度且熱流層流體為純水下，不同操作參數對於透膜通量之影響	                                76
圖5-2-4 冷流層固定15℃進口溫度且熱流層流體為鹽水下，不同操作參數對於透膜通量之影響	                                76
圖5-2-5 冷流層固定25℃進口溫度且熱流層流體為鹽水下，不同體積流對於主流區域、熱流層薄膜表面與冷凝液表面溫度分佈之影響	        79
圖5-2-6 冷流層固定15℃進口溫度且進料端流體為鹽水時，不同體積流對於主流區域、熱流層薄膜表面與冷凝液表面溫度分佈之影響	        79
圖5-2-7 冷流層固定25℃進口溫度且熱流層流體為鹽水時，不同操作參數於溫度極化係數之影響	                                80
圖5-2-8 冷流層固定25℃進口溫度且熱流層流體為鹽水時，不同操作參數於溫度極化係數之影響	                                80
圖5-3-1 冷流層固定25℃進口溫度且熱流層流體為純水下，不同通道表面相對粗糙度與操作參數對於透膜通量之影響                        86
圖5-3-2 冷流層固定25℃進口溫度且熱流層流體為鹽水下，不同通道表面相對粗糙度與操作參數對於透膜通量之影響	                86
圖5-3-3 冷流層固定15℃進口溫度且熱流層流體為純水下，不同通道表面相對粗糙度與操作參數對於透膜通量之影響	                87
圖5-3-4 冷流層固定15℃進口溫度且熱流層流體為鹽水下，不同通道表面相對粗糙度與操作參數對於透膜通量之影響	                87
圖5-3-5 冷流層固定25℃進口溫度且熱流層流體為鹽水下，不同通道表面相對粗糙度於對於主流區、熱流層薄膜表面與冷凝液表面溫度分佈之影響	92
圖5-3-6 冷流層固定25℃進口溫度且熱流層流體為鹽水時，不同通道表面相對粗糙度於對於主流區、熱流層薄膜表面與冷凝液表面溫度分佈之影響	92
圖5-3-7 冷流層固定25℃進口溫度且熱流層流體為鹽水下，不同通道表面相對粗糙度與操作參數於溫度極化係數之影響	                93
圖5-3-8 冷流層固定15℃進口溫度且熱流層流體為鹽水下，不同通道表面相對粗糙度與操作參數於溫度極化係數之影響	                93
圖C-1 薄膜兩側以不同支撐層之示意圖(A)兩側均為尼龍線、(B)一側尼龍線、一側碳纖維板、(C)兩側碳纖維板	                        132
圖C-2薄膜兩側以不同支撐層之實驗結果	                133

表目錄
表1-1 全球水資源蘊含量分佈情形	             2
表1-2不同操作型態之薄膜蒸餾應用領域	             5
表3-1 經驗式參數表                             37
表3-2 模組相關參數	                            53
表3-3 疏水性薄膜(聚四氟乙烯+聚丙烯複合膜)相關參數   53
表3-4流體相關參數	                            53
表3-5流體相關參數式	                    54
表4-1 PTFE/PP複合膜之薄膜性質                  60
表4-2 表面粗糙化之鋁板規格數據表	            64
表4-3 物質表面絕對粗糙度比較表	            65
表5-1-1 納賽數經驗公式所需實驗數據之操作變因表      67
表5-2-1 冷流層固定25℃度進口溫度下，平板型氣隔式薄膜蒸餾系統實驗值與理論值之相對誤差比較表                              77
表5-2-2 冷流層固定15℃進口溫度下，平板型氣隔式薄膜蒸餾系統實驗值與理論值之相對誤差比較表	                             78
表5-2-3 不同操作參數下於平均溫度極化係數之影響比較表  81
表5-3-1冷流進口25℃且熱流流體為純水下，不同通道表面相對粗糙度與操作參數之實驗與理論值相對誤差比較表                      88
表5-3-2冷流進口25℃且熱流流體為鹽水下，不同通道表面相對粗糙度與操作參數之實驗與理論值相對誤差比較表	                     89
表5-3-3冷流進口15℃且熱流流體為純水下，不同通道表面相對粗糙度與操作參數之實驗與理論值相對誤差比較表	                     90
表5-3-4冷流進口15℃且熱流流體為鹽水下，不同通道表面相對粗糙度與操作參數之實驗與理論值相對誤差比較表	                     91
表5-4-1 在不同通道相對粗糙度與操作參數下理論透膜通量增益比例表   98
表5-4-2 在不同通道相對粗糙度與操作參數下理論透膜通量增益比例表   99
表5-4-3 純水進料下，不同通道表面相對粗糙度與操作參數之水力損耗提升程度比較表                                                   100
表5-4-4 鹽水進料下，不同通道表面相對粗糙度與操作參數之水力損耗提升程度比較表                                                   101
表5-4-5 不同通道表面相對粗糙度與操作參數下，理論透膜通量增益程度與水力損耗提升程度比值                                           102
表A-1 經驗公式迴歸所需數據表(在不同操作參數且通道壁面粗糙度為14um下，熱流層流體為純水之實驗數據)                                  120
表A-2 經驗公式迴歸分析數據表(在不同操作參數且通道壁面粗糙度為14um下，熱流層流體為鹽水之實驗數據)                                  121
表A-3 經驗公式迴歸分析數據表(在不同操作參數且通道壁面粗糙度為229um下，熱流層流體為純水之實驗數據)                                 122
表A-4經驗公式迴歸分析數據表(在不同操作參數且通道壁面粗糙度為229um下，熱流層流體為鹽水之實驗數據)                                   123
表A-5經驗公式迴歸分析數據表(在不同操作參數且通道壁面粗糙度為437um下，熱流層流體為純水之實驗數據)                                  124
表A-6經驗公式迴歸分析數據表(在不同操作參數且通道壁面粗糙度為437um下，熱流層流體為鹽水之實驗數據)                                  125
表B-1理論計算下之數據表(在不同操作參數且通道壁面粗糙度為14um下，熱流層流體為純水之實驗數據)                                        126
表B-2理論計算下之數據表(在不同操作參數且通道壁面粗糙度為14um下，熱流層流體為鹽水之實驗數據)                                        127
表B-3理論計算下之數據表(在不同操作參數且通道壁面粗糙度為229um下，熱流層流體為純水之實驗數據)                                        128
表B-4理論計算下之數據表(在不同操作參數且通道壁面粗糙度為229um下，熱流層流體為鹽水之實驗數據)                                        129
表B-5理論計算下之數據表(在不同操作參數且通道壁面粗糙度為437um下，熱流層流體為純水之實驗數據)                                        130
表B-6理論計算下之數據表(在不同操作參數且通道壁面粗糙度為437um下，熱流層流體為鹽水之實驗數據)                                        131

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