本研究實驗是利用Toyo公司所生產之聚四氟乙烯(Polytetrafluoroethylene；pore size=0.2μm)比較直接接觸式薄膜蒸餾(Direct Content Membrane Distillation)與真空式薄膜蒸餾(Vacuum Membrane Distillation)兩者系統用於海水淡化時之效能。實驗是以原型模組與改良模組(凸出型)改變進料溫度、進料流量、曝氣，比較兩系統其滲透通量之差異與影響。
實驗結果可以發現，提高進料溫度對於兩系統皆能明顯增加滲透通量，極化現象也較嚴重。而增加進料流在VMD系統提升通量之效能比DCMD來得高。改變模組傾斜角則是由於不穩定自然對流的關係使得滲透通量提昇，在DCMD系統時皆能提昇滲透通量，其中以傾斜角度45o為最高之滲透通量，但在VMD系統自然對流效果不顯著，對於滲透通量提昇無提昇效果。曝氣時於DCMD系統皆能有效提升通量，VMD則在傾斜角大於45o曝氣才有效果。改良凸出模組(Convex)增加了對膜面之剪應力，對於VMD與DCMD系統皆能有效減緩極化效應使得滲透通量增加，通量提升分別可達15.8%與37.3%。

The flat PTFE membrane and hollow fiber PVDF membrane were used in studying on the flux performance in the operating of DCMD and VMD. Operating parameters included temperature difference, feed flow rate, module inclination angle,  gas flow rate. The convex design in the feed chance was also included.
The experimental results show that increasing the temperature difference will increase the permeate flux, but also heighten the polarization phenomena. The performance of Increasing feed flow in DCMD system higher than VMD system. In DCMD system, the permeate flux increased, and reached a maximum at about 45°. Aeration in DCMD system can enhance the flux, but VMD in the angle greater than 45o aeration will be effective. It is noted that the convex design in the feed channel as module inclined increases the shear stress on the membrane, thus, effectively reduces the polarization phenomena and increases the permeate flux. The flux enhancement in DCMD and VMD were improved to about 37.3% and 15.8% percent.

目錄
誌謝	I
中文摘要	II
英文摘要	III
目錄	IV
圖目錄	VI
表目錄	VIII
第一章	緒論	1
1.1	前言	1
1.2	薄膜分離程序	2
1.3	薄膜蒸餾	5
1.4	研究目標	7
第二章	文獻回顧	10
2.1	薄膜蒸餾相關研究	10
2.2	薄膜蒸餾法之種類	13
2.2.1  直接接觸式薄膜蒸餾	13
2.2.2  空氣間隙式薄膜蒸餾	13
2.2.3  空氣掃掠式薄膜蒸餾	14
2.2.4  真空式薄膜蒸餾	14
2.3	薄膜之性質	15
2.4	影響滲透通量的因素	17
2.5	膜組及操作程序的改良	19
2.5.1	氣液兩相流動	20
2.5.2	模組傾斜角度	22
2.5.3	減少結垢問題	22
2.5.4	改良膜組設計	24
第三章	實驗裝置與方法	30
3.1	實驗裝置	30
3.2	實驗設備	32
3.3	實驗藥品與薄膜材料	33
3.3.1  實驗藥品	33
3.3.2  海水前處理	33
3.4	實驗步驟	34
3.4.1  DCMD實驗步驟	34
3.4.2  VMD實驗步驟	34
3.5	操作條件	36
3.5.1  DCMD 操作條件	36
3.5.2  VMD 操作條件	36
3.6	流量計校正與雷諾數計算	38
3.7	分析方法	39
3.7.1  鹽類含量之分析方法與條件	39
3.7.2  鹽類阻隔率之計算	39
第四章	結果與討論	51
4.1	原型模組之滲透通量	51
4.1.1	進料流量與溫度對滲透通量之影響	51
4.1.2	改變模組傾斜角之滲透通量之影響	52
4.1.3	傾斜模組下曝氣對滲透通量之影響	53
4.2	凸出模組(CONVEX)之薄膜滲透通量	56
4.2.1	進料流量對滲透通量之影響	56
4.2.2	改變模組傾斜角度對滲透通量之影響	57
4.2.3	傾斜模組下曝氣對滲透通量之影響	58
4.3	阻隔鹽類之效能	60
第五章	結論	70
符號說明	72
參考文獻	73
附錄A	77

圖目錄
圖1.1   薄膜分離程序之分類 [Cheryan, 1998]	8
圖1.2   薄膜蒸餾物流流動示意圖	9
圖2.1	DCMD 示意圖	26
圖2.2	AGMD 示意圖	26
圖2.3	SGMD 示意圖	27
圖2.4	VMD 示意圖	27
圖2.5	逆洗程序示意圖 [Mulder, 1991]	28
圖2.6	流體亂流產生器	29
圖3.1	DCMD 模組示意圖	40
圖3.2	DCMD與VMD 模組設計示意圖(進料側)	41
圖3.3	DCMD 模組設計示意圖(冷卻水側)	42
圖3.4	VMD 模組設計示意圖(真空側)	43
圖3.5	渠道凸起模組設計示意圖	44
圖3.6	直接接觸薄膜蒸餾實驗裝置圖	45
圖3.7	真空式薄膜蒸餾實驗裝置圖	46
圖3.8	進料流體流量計校正曲線	47
圖3.9	冷卻水流體流量計校正曲線	47
圖3.10	進料流體流量與Reynolds number之關係圖	48
圖3.11	冷卻水流體流量與Reynolds number之關係圖	48
圖4.1	PTFE平版薄膜於DCMD與VMD在不同進料溫度下改變不同進料流率之滲透通量	61
圖4.2	PVDF中空纖維膜於DCMD與VMD在不同進料溫度下改變不同進料流率之滲透通量	61
圖4.3	DCMD不同模組傾斜角之滲透通量	62
圖4.4	VMD不同模組傾斜角之滲透通量	62
圖4.5	DCMD於不同傾斜角下通入氣體之滲透通量	63
圖4.6	VMD於不同傾斜角下通入氣體之滲透通量	63
圖4.7	VMD於0o時不同曝氣速度之滲透通量變化	64
圖4.8	DCMD於不同進料流量下凸出模組對於滲透通量的影響	64
圖4.9	VMD於不同進料流量下凸出模組對於滲透通量的影響	65
圖4.10	DCMD於不同凸出位置上於不同進料流量下之滲透通量	65
圖4.11	VMD於不同凸出位置上於不同進料流量下之滲透通量	66
圖4.12	DCMD凸出模組於不同傾斜角度下對於滲透通量之影響	66
圖4.13	VMD凸出模組於不同傾斜角度下對於滲透通量之影響	67
圖4.14	DCMD凸出模組於不同傾斜角度下曝氣對於滲透通量之影響	67
圖4.15	VMD凸出模組於不同傾斜角度下曝氣對於滲透通量之影響	68
圖4.16	DCMD不同溫度差下改變進料流量之滲透液導電度與濃度	68
圖4.17	VMD不同溫度差下改變進料流量之滲透液導電度與濃度	69
圖A    NaCl檢量線	77

表目錄
表1.1 	不同操作程序之驅動力分類 [Cheryan, 1998]	8
表3.1	平板薄膜性質說明	49
表3.2	PVDF 中空纖維膜性質說明(UMP-0047R)	50

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