在掃流微過濾進行之中，懸浮液中之微粒除受濾液拉曵力朝薄膜表面傳輸之運動外，同時也受偏移浮升力、剪力、電雙層斥力及擴散之作用而產生逆傳輸離開薄膜表面，最後微粒之傳輸與逆傳輸速度相等而達到平衡，使聚積在濾面之濾餅厚度不再增加，而濾速亦能保持一穩定狀態。而本研究係以流體力學微粒傳輸理論配合質量平衡，來分析在管狀型掃流微過濾器之過濾管道中微粒受力情形與薄膜表面微粒沈積量之關係，進而推導出一數學模式來預測掃流微過濾法之濾速隨時間變化情形，並以改變在不同操作參數所得之實驗結果來驗證數學模式之正確性。
實驗中過濾渠道之流況均控制在層流範圍，由實驗之結果吾人發現:非穩定濾速隨操作壓力差、掃流流速及薄膜孔徑之增大而增大，而隨微粒濃度之增大而減小，另求數學模式對非穩定濾速之預測值與實驗值相當吻合。 In this study, a tubular ceramic membrane was used to investigate the decline of permeate flux with time in crossflow microfiltration under various operating conditions; Including cross flow velocity, pressure drop, particle concentration and membrane pore size. It was found that the unsteady state permeate flux increased wlth increasing cross flow velocity, membrane pore size and pressure drop. but it decreased with increasing particle concentration in a suspension. Furthermore,a mathematical model based on two-coupled transport phenomena of particles, was developed in this study. It satisfactorily predicted the unsteady state permeate flux of crossflow microfiltration under various operating conditions.
