Granular filtration has been incorporated as a major barrier to prevent the dissemination of disease-causing agents by drinking water. Particles and pathogens such as Giardia lamblia and Cryptosporidium parvum retained in the filters are then washed by utilizing clean water. This study was conducted, primarily, to evaluate coagulation as a pretreatment for the Spent Filter Backwash Water (SFBW) treatment by ultrafiltration (UF). SFBW Samples were collected from four different water treatment plants and carefully analyzed. Jar-tests and backwash pilot studies were performed in the laboratory. Depending on the water source, protozoan parasites and viruses were found to be prevalent in SFBW. The results show that turbidity cannot serve as a surrogate for the microbial load of the SFBW. Alum flocculation pretreatment of SFBW was found to be effective in reducing turbidity, particle count, viruses and parasites, consequently it may also reduce membrane fouling. Settling the SFBW prior to flocculation did not enhance the removal of turbidity and particle count as compared to the unsettled SFBW samples. This finding might imply that settling would not be required prior to UF. The largest remaining particle fraction after alum flocculation was 3-10 μm in size, both Cryptosporidium and Giardia are found in this size range. Coagulation enhanced the removal of small size particles and may result in extending the filtration cycle by reducing the SFBW fouling potential.
Skip Nav Destination
Article navigation
Research Article|
December 01 2002
Coagulation as a pretreatment of SFBW for membrane filtration Available to Purchase
A. Nasser;
*Water Quality Research Laboratory, Ministry of Health, P.O.Box. 8255, Tel-Aviv 61082, Israel
E-mail: [email protected]
Search for other works by this author on:
Z. Huberman;
Z. Huberman
*Water Quality Research Laboratory, Ministry of Health, P.O.Box. 8255, Tel-Aviv 61082, Israel
Search for other works by this author on:
L. Dean;
L. Dean
**Division of Environmental Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
Search for other works by this author on:
F. Bonner;
F. Bonner
**Division of Environmental Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
Search for other works by this author on:
A. Adin
A. Adin
**Division of Environmental Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
Search for other works by this author on:
Water Supply (2002) 2 (5-6): 301–306.
Citation
A. Nasser, Z. Huberman, L. Dean, F. Bonner, A. Adin; Coagulation as a pretreatment of SFBW for membrane filtration. Water Supply 1 December 2002; 2 (5-6): 301–306. doi: https://doi.org/10.2166/ws.2002.0183
Download citation file:
Sign in
Don't already have an account? Register
Client Account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.
eBook
Pay-Per-View Access
$38.00