Membrane fouling of fine colloids and biocolloids is ubiquitous in pressure-driven
membrane processes, such as microfiltration (MF), ultrafiltration (UF), nanofiltration
(NF), and reverse osmosis (RO). In MF/UF, colloidal fouling is initiated by rapid
formation of the concentration polarization (CP) layer, and is significantly enhanced by
gradual development of the cake layer of colloidal maximum packing. In RO/NF, the
hydraulic resistances from the CP and cake layers are, however, negligible compared to
the membrane resistance. |
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