In this study, the fouling behavior of nanofiltration (NF) and reverse osmosis
(RO) membranes during filtration of feed water containing both inorganic colloidal
materials and dissolved organic matter (DOM) was investigated. Fouling experiments
were systematically performed in a cross-flow filtration system with both NF and RO
membranes to determine how interactions between DOM compounds and colloidal
materials affect the fouling process and hence membrane permeate flux. Two organic
macromolecules of distinct adsorptive properties, dextran and bovine serum albumin
(BSA), were used as model DOM compounds. In all cases, flux decline in combined
fouling by feed waters containing both inorganic colloidal materials and DOM was
significantly higher than the additive sum of contributions from individual foulants. Two
different mechanisms causing the observed synergistic effect in combined fouling were
identified: hindered back diffusion and macromolecule mediated colloidal interaction.
The controlling mechanism depends on the type of organic macromolecules. It was also
found that the physical properties of the combined fouling layer and its impact on
membrane flux and salt rejection highly depend on the salt rejection of the membrane. Includes 8 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 180 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 10 |
| Published : | 11/01/2007 |
