Abstract
本研究乃利用管狀型薄膜及微過濾器, 在不同操作條件及採用逆洗和 脈衝二種去阻塞方法進行過濾,以尋求一最佳之操作條件,另也將推導一逆 洗模式來和實驗結果作比較 實驗分成混凝實驗與過濾實驗二部分, 在 混凝實驗部分,首先將混凝劑多元氯化鋁加入銅或鋁離子,利用杯瓶試驗法 求得最佳膠凝條件pH=7.5, PAC=20ppm; 在過濾實驗部分當改變操作條件, 如掃流速度增大. 濃度降低. 溫度升高.壓力增大. 薄膜孔俓增大均能讓 濾速增大 各種脈衝中以2分關2秒的濾液脈衝最好,操作150分鐘,銅離子的 濾液通量增加31.2%,濾液總量增加14.67%, 而鋁離子濾液通量增加39.32% 濾液總量增28.96%; 逆洗因能將濾餅再度揚起 所以去阻塞效果最好另做 逆洗模式探討,結合Chang(1995)之數學模式與實驗求得的實驗式來和實驗 數據比較, 發現我們可獲得不錯的符合結果 Tubular crossflow microfiltration cell was installed to investigate the variation of permeate flux with filtration time under various operating conditions including flocs concentration, pressure drop, temperature, crossflow velocity, pH and membrane pore size, and we also linkup pulsating and backwashing to investigate the variation of permeate flux. The first, used coagulation experimental to decide this optimum operation of coagulation in pH=7.5、PAC=20ppm. It was found that the un-steady state permeate flux increased with an increased in pressure drop, temperature, crossflow velocity, or membrane pore size, but decreased with an increased in flocs concentration in the suspension. In the pulsing and backwashing, they were found that the un-steady state permeate flux all increase. among this pulsating permeate flux(valve 5 was closed 2 seconds in every 2 minutes of operation) and backwashing(valve 6 was closed 2 seconds in every 5 minutes of operation) were the best. Finally, we found backwashing model based on Chang(1994) mathematical model and experiment formula. This model predicts satisfactorily the un-steady state permeate flux of CFMF under backwashing.