This slide presentation outlines a study on comparing the effectiveness
of microfiltration (MF) vs. ultrafiltration (UF) pretreatment on nanofiltration (NF)
and reverse osmosis (RO) membrane performance related to
water quality,
fouling rates, and
virus rejection. The study also
autopsied high-pressure membranes
to evaluate foulant accumulation, and developed bench-scale tests
to measure the effect of operating
conditions on long-term fouling related to
backwash, FeCl<sub>3</sub> dose, and
foulant accumulation. Experimental methods included:
MF/RO and UF/RO operated in parallel;
monitored flows and pressures;
periodic measurement of water quality (WQ) parameters;
simultaneous bench-scale testing;
virus challenge studies; and,
membrane autopsy at end of study. A program at the North Buffalo WRF in
Greensboro, North Carolina is outlined. Conclusions drawn included: less RO fouling by UF than MF
pretreatment;
extent of RO fouling is still significant;
polysaccharides implicated as foulant,
though little difference in dissolved organic carbon (DOC) rejection
between UF and MF;
colloidal removal by FeCl<sub>3</sub> in UF
not understood; 4-5 log removal of virus by RO, but virus
found in some permeates;
virus removal increases with fouling
of MF and UF;
membrane permeate quality suitable
for many reuse applications; and,
additional work necessary to evaluate
engineering significance of results. Includes tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 1 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 54 |
| Published : | 03/01/2007 |
