薄膜蒸餾法兼具傳統薄膜法和蒸餾法的優點，未來極可能取代其他如傳統蒸餾法與逆滲透等技術，本文將針對薄膜蒸餾法在實用化與商業化上所遭遇到的困難，如汙堵問題、能源效率利用差、未選用適當薄膜，來提出有效的對策。
　　關於處理薄膜的汙堵問題，由之前的研究成果顯示，利用UV殺菌再加上微或超微過濾的前處理系統，能非常有效地減緩薄膜汙堵，使滲透量提高，運轉時間延長。再配合超音波清洗，能有效地清除薄膜汙堵，並且使衰退的滲透量回復。
　　本文最主要之重點在於如何提升能源之使用效率，吾人採用多效蒸餾的省能概念，設計出具有高效率熱交換之迴路，在主要測試段(蒸餾實際發生處)之尺寸採用EGM最佳化法來求得。
　　現階段省能實驗設備的製作與架設已經完成，管路接頭的洩漏與測試段保溫問題已經解決，系統測試也顯示流體之溫度及流量的穩定性良好，當取得較好較大的MD膜時，即可執行更多之測試，以獲得更佳的實驗結果。

　　Membrane distillation (MD) possess almost all the good features that can be found in both conventional membrane method and conventional distillation method. Seawater desalination by MD (SWMD) is not yet commercially available due to the problems such as membrane fouling, poor effectiveness in heat consumption, and lack of a tailor-made membrane for MD.
　　The results obtained from previous tests indicate the application of UV light + MF/UF as the pretreatment method for SWMD can be a very effective way to slow down the fouling process and extend the operation time. By the use of ultrasonic cleaning technique, the foulant on the membrane can be effectively shocked off and restore the membrane’s permeate flux.
　　The main task of this paper is focused on the efficiency improvement in the ultilization of heating energy during the MD processes. The concept of multi-effect distillation has been adopted in this study to design an energy-efficient flow loop. The channel configurations of main test-section where the distillation process is actually occur is optimized by the application of entropy generation minimization (EGM).
　　The set-up of energy-efficient test facility has been completed. The leakage problem found at some pipe joints and the thermal insulation surrounding the test section have been resolved. The test runs were conducted smoothly. More test data will be collected whenever a better and larger MD membrane is available.

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