本研究探討操作條件對微粒子/牛血清蛋白雙成份懸浮液之沉浸式薄膜過濾的影響，使用表面平均孔徑為5.6 μm之管狀陶瓷薄膜，過濾粒徑為15 μm之聚甲基丙烯酸甲酯（PMMA）圓球形粒子，以及分子量67000 Da之牛血清蛋白（BSA）。利用薄膜阻擋懸浮溶液中的固體粒子，而讓部分牛血清蛋白通過薄膜孔道，以達到分離的效果。本研究探討過濾壓差、逆洗時間、逆洗頻率、逆洗通量、曝氣通量以及階梯式提高過濾壓差等操作條件對過濾效能之影響。結果顯示：過濾主要的阻力來源為薄膜孔洞阻塞。逆洗操作，能夠提升過濾速度，主要是因為減少薄膜表面濾餅的成長，該操作並可提升牛血清蛋白的穿透率。實驗結果亦得知在低逆洗通量以及較短的逆洗時間下，會有較佳的分離效率。曝氣只能有效減少濾餅阻力，但對於薄膜內部阻力沒有太大的減緩效果。而以階梯式提升過濾壓差操作時，能夠大幅減少薄膜內部孔洞阻塞，並能更有效的提升濾速以及分離效率。本研究並經由理論的分析以及實驗的結果，得知在過濾初期，過濾阻力的來源主要來自薄膜內部阻力，並符合中間阻塞模式，當過濾一段時間之後，則轉變為濾餅阻塞模式。 The effects of operating conditions, such as filtration pressure, backwash time, backwash duration, backwash flux, aeration intensity and step increase pressure, on the performance of submerged membrane filtration are studied. A ceramic membrane tube with a mean surface pore size of 5.6 μm, is used to filter PMMA particles with a mean diameter of 15μm and BSA（MW=67000 Da）. PMMA particles are retained by the filter membrane during filtration, while some BSA molecules may permeate through the filter cake and membrane into the filtrate. The experimental results show that the filtration resistance due to membrane blocking plays the major role on the overall filtration resistance. The filtration rate increases by performing backwash because of the cake reduction and BSA increase. A lower backwash flux or shorter backwash time is better for flux enhancement. Aeration operation can effectively reduce the cake resistance, but no significant effect on internal resistance reduction can be found. In addition, the filtration rate can be significantly enhanced by increasing filtration pressure step-wise. It is because of the decrease in membrane blocking resistance. The model analysis and experimental result shows that the intermediate blocking occurs at the beginning of filtration. However, the blocking model changes to cake filtration after a period of time.
