教師資料查詢 | 類別: 期刊論文 | 教師: 黃國楨 Hwang, Kuo-Jen (瀏覽個人網頁)

標題:The Role of Elastic Effect in Filtration of Particles Suspended in Viscoelastic Polymeric Solution
學年90
學期1
出版(發表)日期2001/11/01
作品名稱The Role of Elastic Effect in Filtration of Particles Suspended in Viscoelastic Polymeric Solution
作品名稱(其他語言)彈性效應在過濾懸浮於黏彈性高分子流體中之粒子所扮演之角色
著者黃國楨; Hwang, Kuo-jen; 陳育翔; Chen, Yuh-shyang
單位淡江大學化學工程與材料工程學系
出版者臺北市中國化學工程學會
著錄名稱、卷期、頁數Journal of the Chinese institute of chemical engineers=中國化學工程學會會誌 32(6), pp.529-536
摘要The effect of the elastic property of a fluid on the mechanism of cake filtration is studied. The elongation flow of the viscoelastic fluid through the filter cake results in lower porosity and higher filtration resistance of the cake. At the beginning of filtration, the elastic behavior of the fluid plays an important role in the performance of filtration since the filtration rate is higher at that time. The elastic effect then vanishes after a period of time due to attenuation of the filtration rate, and the flow behavior of the fluid is transformed according to the power law. The cake properties are calculated using the dynamic analysis method. The average cake porosity decreases with time at the beginning of filtration due to the elastic effect of the fluid and then increases and approaches a constant value when the flow behavior of the fluid is transformed to purely viscous behavior. The dumbbell model is used to explain the "roil-stretch" behavior of the polymer chain during filtration, while the Deborah number is used to predict the occurrence of elastic behavior of the suspension. The critical Deborah number, at which the elastic effect of the fluid vanishes, is evaluated and discussed. The experimental results show that the critical Deborah number increases with increasing filtration pressure, and that the dumbbell model can only be applied when the filtration pressure is less than 1 X HP N/m2. The resistance coefficient is defined and used to predict the critical vanishing point of the elastic effect under various conditions. The critical resistance coefficient is a constant for a given concentration of PAA regardless of the Reynolds number or operating conditions. An increase in the polymer concentration causes the critical resistance coefficient to decrease.;本研究探討流體之彈性在濾餅過濾中之效應。黏彈性流體流經濾餅之拉伸流動(elongation flow) 會造成低孔隙度與高過濾阻力的濾餅。在過濾初期,因為濾速較高,所以流體之彈性行為在過濾性能上扮演極為重要的角色。而當經過一段時間後,由於濾速的衰減,使得彈性效應消失,流體之行為轉為遵循幕次定律(power law) 。濾餅之性質採用動態解析法計算。在過濾初期,濾餅之平均孔隙度因為流體之彈性效應而逐漸降低;但是當此效應消失後,濾、餅孔隙度即逐漸增加,並趨近一定值。一啞鈴模型(dumbbell model)被採用來說明高分子鏈的“捲繞-伸展" (coil-stretch)行為;且Deborah 數被用來預測流體彈性行為的發生。在不同的操作條件下,彈性效應正好消失的臨界Deborah 數被計算且深入討論。實驗結果顯示:臨界Deborah 數隨過濾壓差之增加而增加,但是啞鈴模型只能適用在過濾壓差小於1 x 10^5 N/m^2 的範圍。本研究並定義一”阻力係數"來預測彈性消失的臨界點,在固定的高分子濃度下,臨界阻力係數為一定值,與雷諾數(Reynolds number)或操作條件無關。高分子濃度的增加會導致臨界阻力係數的降低。
關鍵字Constant pressure filtration; Viscoelastic fluid; Cake properties, Filtration; Dynamic analysis; Polymeric solution
語言英文
ISSN0368-1653
期刊性質國內
收錄於SCI;EI
產學合作
通訊作者
審稿制度
國別中華民國
公開徵稿
出版型式紙本
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