English  |  正體中文  |  简体中文  |  全文筆數/總筆數 : 51296/86412 (59%)
造訪人次 : 8175061      線上人數 : 79
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library & TKU Library IR team.
搜尋範圍 查詢小技巧:
  • 您可在西文檢索詞彙前後加上"雙引號",以獲取較精準的檢索結果
  • 若欲以作者姓名搜尋,建議至進階搜尋限定作者欄位,可獲得較完整資料
  • 進階搜尋
    請使用永久網址來引用或連結此文件: http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/77446


    題名: 雙效型直接接觸式薄膜蒸餾於海水淡化之研究
    其他題名: The study of double-effect direct contact membrane distillation on seawater desalination
    作者: 陳俊男;Chen, Chun-Nan
    貢獻者: 淡江大學化學工程與材料工程學系碩士班
    何啟東;Ho, Chii-Dong
    關鍵詞: 薄膜蒸餾;海水淡化;薄膜係數;溫度極化;Direct contact membrane distillation;Desalination;membrane coefficient;temperature polarization;semi-empirical correlation
    日期: 2012
    上傳時間: 2012-06-21 06:44:06 (UTC+8)
    摘要: 薄膜蒸餾為海水淡化技術之一,用來製造純水提供民生及工業使用。其特色為占據體積小、可操作在常壓、低溫熱源與可模組化等優點。本研究主要針對在薄膜蒸餾系統中,薄膜係數為預測理論純水透膜通量之重要參數。因此本研究將以攪拌型直接接觸式薄膜蒸餾系統,藉由改變不同操作條件,求得薄膜兩側膜面溫度,再利用最小平方法建立一薄膜係數經驗公式。進而建立雙效型直接接觸式薄膜蒸餾系統之二維數學模型,對其質量與熱量傳送機制進行研究,並將薄膜係數經驗公式代入,以實驗分析輔以驗證數學模型之正確性。本研究求解是先利用有限差分法將偏微分方程式簡化,再使用四階Runge-Kutta數值方法求解,得到通道內溫度分佈及理論純水透膜通量。研究結果顯示雙效型直接接觸式薄膜蒸餾系統實驗值與理論值平均相對誤差(1)純水:3.97%;(2)鹽水:5.46%。結果顯示,純水透膜通量會因提升攪拌轉速、提升熱側進口流體溫度與提升體積流率而增加。溫度極化係數隨著攪拌轉速的提升與進口體積流率增加而趨近於1。
    The direct contact membrane distillation(DCMD) device is a simple design of MD systems in which both the cold stream and hot stream are kept in direct contact with the membrane. The advantages of DCMD lie in its simple configuration, the need for only small temperature differences and nearly 100% salt rejection. In this study, the DCMC process are performed at middle temperature operation (about 40 °C to 70 °C) of hot inlet stream associated with a constant cold stream inlet temperature(about 25 °C). A concurrent flat-plate device was constructed and carried out to verify the theoretical prediction of pure water productivity on saline water desalination. The purposes of this study are (1) to develop a new semi-empirical expression of the membrane coefficient from the results of the pure water production of the experiment and the mathematical modeling; (2) to study a new design of double-effect direct contact membrane distillation system and develop a two-dimensional mathematical model and propose a general numerical method for solving this complex mathematical model in predicting pure water productivity in membrane distillation systems. The numerical results from the mathematical modeling of the resultant partial differential equations were obtained using the finite difference technique of the fourth-order Runge-Kutta method. The influences of the inlet saline water temperature and volumetric flow rate on the pure water productivity as well as the hydraulic dissipated energy are also delineated.
    顯示於類別:[化學工程與材料工程學系暨研究所] 學位論文

    文件中的檔案:

    檔案 大小格式瀏覽次數
    index.html0KbHTML150檢視/開啟

    在機構典藏中所有的資料項目都受到原著作權保護.

    TAIR相關文章

    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library & TKU Library IR teams. Copyright ©   - 回饋