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Improvement of Membrane Performance by Natural Convection Instability Flow in Ultrafiltration of Colloidal Solutions  

Cho, Youn-Joo (Department of Industrial Engineering Chemistry, Chungbuk National University)
Youm, Kyung-Ho (Department of Industrial Engineering Chemistry, Chungbuk National University)
Publication Information
Membrane Journal / v.21, no.1, 2011 , pp. 84-90 More about this Journal
Abstract
We studied the effects of induction of natural convection instability flow (NCIF) according to the gravitational orientation (inclined angle) of the membrane cell on the reduction of membrane fouling in ultrafiltration (UF) of colloidal silica solutions. Five colloidal silica solutions with different silica size (average size = 7, 12, 22, 50 and 78 nm) were used as UF test solutions. The silica particles in colloidal solutions form cakes on the membrane surface thereby causing severe reduction in the flux. The UF performance according to the gravitational orientation of the membrane cell (from 0 to $180^{\circ}$ inclined angle), was examined in an unstirred dead-end cell. We evaluate the effects of NCIF on membrane performance as the flux enhancement ($E_i$). In the dead-end UF of smaller size (7, 12 and 22 nm) silica colloidal solutions, changing the gravitational orientation (inclined angle) of the membrane cell induces NCIF in the membrane module and higher inclined angle and smaller size silica colloidal solution offer more stronger NCIF. This induced NCIF enhances back transport of the deposited silica solutes away from the membrane surface, therefore gives for the improvement of permeate flux. But in UF of more larger size (50 and 78 nm) silica colloidal solutions, NCIF effects are not appearing. These results suggest that the size of colloidal particle affects the extent of NCIF occurrence.
Keywords
ultrafiltration; natural convection instability; membrane fouling; reduction of fouling; flux enhancement colloidal silica solution;
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Times Cited By KSCI : 2  (Citation Analysis)
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1 S. T. Nam and M. J. Han, "Fouling behavior of bentonite colloidal suspensions in microfiltration", Membrane Journal, 18(1), 53 (2008).
2 J. W. Chang, K. M. Ahn, K. H. Kim, S. Khan, and J. H. Kim, "Mitigations of natural organic matter fouling of polyethersulfone microfiltration membrane enhanced by deposition of $TiO_{2}$ nanoparticles", Membrane Journal, 20(2), 120 (2010).
3 A. D. Marshall, P. A. Munro, and G. Tragardh, "The effect of protein fouling in microfiltration and ultrafiltration on permeate flux, protein retention and selectivity", Desalination, 91, 65 (1993).   DOI   ScienceOn
4 M. Turker and J. Hubble, "Membrane fouling in a constant-flux ultrafiltration cell", J. Membr. Sci., 34, 267 (1987).   DOI
5 M. Hlavacek and F. Bouchet, "Constant flowrate blocking laws and an example of their application to dead-end microfiltration of protein solutions", J. Membr. Sci., 82, 285 (1993).   DOI   ScienceOn
6 Y. Xu-Jiang, J. Dodds, D. Leclerc, and M. Lenoel, "A technique for the study of the fouling of microfiltration membranes using two membranes in series", J. Membr. Sci., 105, 23 (1995).   DOI
7 A. G. Fane and C. J. D. Fell, "A review of fouling and fouling control in ultrafiltration", Desalination, 62, 117 (1987).   DOI
8 H. B. Winzeler and G. Belfort, "Enhanced performance for pressure-driven membrane processes: the argument for fluid instabilities", J. Membr. Sci., 80, 35 (1993).   DOI   ScienceOn
9 K. Y. Chung and G. Belfort, "Performance test for membrane module using Dean vortices", Membrane Journal, 2(2), 104 (1992).
10 T. J. Hendricks, J. F. Macquin, and F. A. Williams, "Observation on buoyant convection in reverse osmosis", Ind. Eng. Chem., Process Des. Dev., 14, 166 (1975).   DOI   ScienceOn
11 K. H. Youm, A. G. Fane, and D. E. Wiley, "Effects of natural convection instability on membrane performance in dead-end and cross-flow ultrafiltration, J. Membr. Sci., 116, 229 (1996).   DOI   ScienceOn