One of the main limitations of membrane applications for water treatment is biofouling,
which causes a decrease of membrane performances and is often very difficult to remove by
chemical cleanings. To act preventively, membrane pretreatment has to be optimized to
minimize the biofouling potential of the feedwater.
This study compares different pretreatment processes implemented upstream from
nanofiltration (NF), and their ability to reduce of biofouling on NF elements.
Two identical one-stage NF membrane pilots were fed different water qualities from two water
treatment plants in France (Neuilly-sur-Marne and Choisy-le-Roi) during several long filtration tests.
Both pilots included a pretreatment step made of pH neutralization, 20 and 6 µm cartridge
filtration (except during test 4), and antiscalant injection. UV disinfection was realized by a pilot reactor containing a low pressure UV lamp operated at
400 J/m<sup>2</sup>. At the end of every test, NF spiral-wound modules were autopsied and analyzed. The
fouling deposit was characterized by ATR-FTIR spectroscopy and by epifluorescence
microscopy (DAPI staining for total bacteria counts, SYTO9-propidium iodide for live/dead
distinction, FTIC and TRITC-conjugated lectins for exopolysaccharides visualization). The
deposit dry weight, wettability, ATP and proteins contents were also determined. This study highlights the importance of pretreatment to control biofouling on NF membranes. Includes 17 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 930 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 15 |
| Published : | 11/01/2009 |
