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论文类型：期刊论文
发表时间：2015-01-01
发表刊物：RSC ADVANCES
收录刊物：SCIE、EI、Scopus
卷号：5
期号：108
页面范围：89095-89104
ISSN号：2046-2069
摘要：Theoretical and experimental investigations were conducted to predict particle deposition and layer growth during formation of a dynamic membrane using cross-flow microfiltration. A critical particle size model was developed and solved in radial, circumferential and axial directions by analyzing the forces acting on a single particle. The model accounted for the normal drag, lateral lift, shear-induced and Brownian diffusion forces in the depositional direction, the van der Waals force in the circumferential direction, and the cross-flow drag and van der Waals forces in the axial direction. Cross-flow velocity and feed temperature were selected as representative influencing factors to examine variations of the critical particle sizes with permeate flux. Experiments were then conducted with carbon tubes as the support and zirconium dioxide particles as the coating material to verify the model. Results showed that a dynamic layer with non-uniform thickness along the circumferential direction was formed within the horizontal tube due to gravity. The layer thickness decreased as the cross-flow velocities were increased under a given transmembrane pressure difference and feed concentration. An appropriately large cross-flow velocity was beneficial to achieve thickness uniformity during formation. The effect of the feed temperature on the critical particle size and layer thickness can be ignored. Comparisons between the theoretical predictions and experimental data of the layer thicknesses displayed good agreements. The effects of transmembrane pressure differences and feed concentrations were finally examined in the present work.