本研究旨在探討通入氣泡對酵母菌的掃流微過濾性能之影響。實驗中使用平均孔徑為0.1 μm的醋酸纖維膜來過濾平均粒徑為4.7 μm之酵母菌粒子；探討操作條件，例如氣體之流量、過濾壓差、液體速度等，對濾速、濾餅性質及濾面上剪切力之影響。實驗結果顯示，當氣體流量越大時，作用於濾面上剪切力也越大，濾餅量會顯著減少，但是也會導致粒子排列的更緊密，使得濾餅之平均過濾比阻增加；綜合濾餅量與過濾比阻兩個因素，則濾餅的總阻力反而會隨這氣體之流量的增加而增加，導致濾速下降。故濾餅的結構或平均過濾比阻亦是影響濾速與過濾阻力的重要因素。此外，提升液體速度掃流速度能夠有效提升濾速，但若速度超過0.3 m/s則反而會導致濾速下降。雖然提升過濾壓差可以增加過濾驅動力，但也會使得濾餅被壓縮的更為緊密、增加濾餅的過濾阻力，進而導致濾速反而下降。 The gas-sparging cross-flow microfiltration of bio-suspension is studied. A filter membrane made of mixed cellulose ester with a mean pore size of 0.1 .mu.m is used for filtering 4.7 .mu.m yeast cells .The effects of operating conditions, such as liquid velocity, gas velocity and filtration pressure, on the filtration rate, cake properties, shear stress acting on the membrane surface are discussed. An increase in gas flow rate leads the shear stress on the membrane surface and the average specific filtration resistance of cake to increase, but the cake mass to decrease. To take these factors into consideration, the overall filtration resistance is increased and the filtration rate is decreased with the increasing the flow rate of sparging gas. In addition, the filtration rate increases with the increase of liquid velocity under low velocity range. When liquid velocity exceeds 0.3 m/s, a contrary tendency is obtained. This is because the cake structure becomes more compact. Since the average specific filtration resistance of cake plays the major role in determining filtration resistance to operate under low liquid velocity range can enhance the filtration rate.