不同變形度軟粒子之微過濾機制

Microfiltration Mechanism of Soft Particle Slurry with Different Deformability

古雅婷(Ya-Ting Ku)

指導教授 ： 童國倫

中原大學/工學院/化學工程學系/碩士(2006年)

https://doi.org/10.6840/CYCU.2006.00469

摘要

本研究藉由戊二醛對可變形酵母菌粒子進行交聯程度的改變，用以產生不同軟硬程度的酵母菌粒子，當交聯程度越高越呈現剛性粒子的特性；實驗操作在掃流與恆壓過濾下，探討不同交聯程度之酵母菌粒子，在不同膜孔洞下的過濾機制。根據研究結果歸納出如下重點，首先是在相同膜孔徑時，隨著酵母菌交聯程度越大，過濾阻力相對變低，過濾通量變大。第二是在不同膜孔徑時，相同的交聯程度下，粒子為可變形時，在膜孔大的通量衰退率較膜孔小的要來的高，因大膜孔初始透過量大，粒子堵塞膜孔道，有較大的通量衰退率；在經過交聯後之粒子，當膜孔徑約等於平均粒徑時，會發生完全堵塞，而有較低的通量。第三是操作在掃流過濾且進料濃度高時，當粒徑約等於孔徑有較高的的穩定通量值。第四是粒子未受交聯時，其濾餅厚度會在過濾初期上升而後下降，因為在過濾初期時，過濾通量較大，濾餅厚度增加，之後過濾通量降低，粒子受力壓縮而使濾餅厚度降低，交聯程度較高時，濾餅累積量則呈線性成長。

關鍵字

聚碳酸酯 ； 交聯 ； 微過濾 ； 戊二醛 ； 恆壓過濾 ； 酵母菌 ； 掃流過濾

並列摘要

In this study, deadend and crossflow microfiltrations of various deformabilities of S. cerevisiae particles were conducted to examine the fouling mechanisms of particle blocking and deposition during initial stage. The S. cerevisiae particles were crosslinked with glutaraldehyde to form various deformability particles. In order to compare the difference of fouling mechanism among various deformability particles during microfiltration, a combined pore blockage and cake filtration model was proposed to estimate the filtration flux. The experimental results firstly indicate that while the crosslinking concentration is increased, the filtration resistance decreased and filtration flux increased under the same pore diameter of membrane. Secondly, for the case of pore diameter/average particle size ca. 1, the filtration showed a complete blocking mechanism for crosslinked particle. Thirdly, in crossflow filtration, when the crosslinking concentration was increased and the membrane pore diameter/average particle size ca. 1, a higher steady state flux is obtained. Fourthly, for deformable particle, the initial cake thickness increased fast because of the higher flux at the beginning of filtration and the subsequent growth of cake thickness decreased because the particles in the cake were compressed. As the crosslinking concentration is increased, the cake thickness grew linearly.

並列關鍵字

crossflow ； deadend ； polycarbonate ； yeast ； glutaraldehyde ； microfiltration ； crosslinking

參考文獻

Altena, F.W., G. Belfort, “Lateral migration of spherical particles in porous channels: Application to membrane filtration,” Chem. Eng. Sci., 29, 343-355 (1984)

Attenborough, F. R., and, K. Kendall, “Cell-cell adhesion of erythrocytes,” J. Adhes. , 74(1-4), 41-51 (2000).

Belfort, G., “Fluid mechanics in membrane filtration: Recent developments,” J. Membr. Sci., 40(2), 123-147 (1989).

Belfort, G., R. H. Davis and A. L. Zydney, “The behavior of suspensions and macromolecular solutions in crossflow microfiltration,” J. Membr. Sci., 96(1-2), 1-58 (1994).

Blake, N. J., I. W. Cumming and M. Streat, “Prediction of steady state crossflow filtration using a force balance model. J. Membr. Sci., 68(3), 205-516 (1992).