薄膜蒸餾製程具備了初置成本低、省能源等優點，有可能取代其他如傳統蒸餾與逆滲透（RO）等的技術，但卻僅止於理論與實驗的探討，目前尚未商業化，其中最主要的原因可能為結垢問題，因薄膜結垢是無法避免的，故結垢清除是MD是否可商業化的一個重要因素。
　　本文使用直接接觸薄膜蒸餾（Direct-Contact membrane distillation）來進行海水淡化實驗，並以真實海水作為飼水。實驗中使用掃瞄式電子顯微鏡(Scanning Electron Microscope, SEM)與敲擊式原子力顯微鏡(dynamic force microscope, DFM)觀察結垢前後薄膜表面形貌的變化，並利用能譜儀(Energy dispersive spectrometer, EDS)分析結垢之組成元而在結垢形成後探討使用超音波去除結垢之可行性。
　　由實驗結果得知，將超音波與檸檬酸配合進行薄膜再生清洗，有極佳的除垢效果與良好的滲透量回復率，且用超音波進行多次再生清洗也不會對薄膜造成破壞。

　　Membrane distillation (MD) is investigated worldwide as a low cost, energy saving alternative to other conventional separation processes such as distillation and reverse osmosis (RO). However, the study of MD is still limited inside the academic community, it has not yet become available for commercial application. Since, the MD process is a thermal-driven method, the membrane fouling is inevitable during a seawater MD process, membrane fouling thus posts as one of the major obstacles for the MD method successfully competing in seawater desalination.
　　In this study, a single stage Direct-Contact Membrane Distillation (DCMD) facility was set up to perform the desalination tests. Real seawater was used as the feeding solution in the tests. The growth shape of membrane fouling was investigated by SEM(scanning electron microscope) and DFM(dynamic force microscope), and the composition of fouling was examinated by EDS(energy dispersive spectrometer).
　　An ultrasonic cleaning device is used in this study to break the fouling layer and clean the membrane scales. The result indicated that the ultrasonic cleaning method and the addition of citric acid into cleaning solution is an effective way to clean up the scale and restore the flux rate without causing damage to the memebrane body.

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