Abstract
A series of well-controlled membrane filtration experiments are performed to systematically investigate the dynamic behavior of permeate flux in crossflow membrane filtration of colloidal suspensions. Results are analyzed by a transient permeate flux model which includes an approximate closed-form analytical expression for the change of permeate flux with time. The model is based on a simplified particle mass balance for the early stages of crossflow filtration before a steady-state flux is attained, and Happel's cell model for the hydraulic resistance of the formed particle cake layer. The filtration experiments demonstrate that permeate flux declines faster with increasing feed particle concentration and transmembrane pressure and with a decrease in the particle size of the suspension. It is also shown that crossflow velocity (shear rate) has no effect on permeate flux at the transient stages of crossflow filtration. Pressure relaxation experiments indicate that the particle cake layer is reversible, implying no irreversible deposition (attachment) of particles onto the membrane surface or the accumulated (retained) particles. The experimental results are shown to be in very good agreement with the theoretical predictions, thus verifying the validity of the model for the transient permeate flux in crossflow filtration and the underlying assumptions in the derivation of the model.
Original language | English |
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Pages (from-to) | 267-277 |
Number of pages | 11 |
Journal | Journal of Colloid and Interface Science |
Volume | 196 |
Issue number | 2 |
DOIs | |
Publication status | Published - 1997 Dec 15 |
Externally published | Yes |
Keywords
- Colloid filtration
- Concentration polarization
- Crossflow membrane filtration
- Membrane fouling
- Particle cake layer
- Permeate flux decline
- Transient flux
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Biomaterials
- Surfaces, Coatings and Films
- Colloid and Surface Chemistry