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CEL 795 Term Paper Report on
“REMOVAL OF BACTERIA BY FILTERATION FROM STORM
WATER”
PREPARED UNDER THE GUIDANCE OF
DR. ARUN KUMAR
ASSTT PROFESSOR IIT DELHI
Submitted by:
Shantanu Parashar
Preeti Dinker
Lalaram
Background and objective
Parameter of concern in rain water :
• Total solids : Dissolved salts, metals, suspended solids
• Pathogens: E. coli, Cryptosporidium, Giardia, Campylobacter,
Vibrio, Salmonella and Pseudomonas
Background: inadequate microbial removal capacity of conventional
sand media
Objective : To Review all present research going on sand media filter
for maximization of removal of bacteria from rain water
Method used
1. Understanding of the hydraulic flow condition within the filter and
comparison with SSF
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•
•
•
Uniform drip flow over the sand surface by use of a plastic or sheet metal diffuser
Depth of the BSF sand layer is about 50% less than for the SSF (0.4 m compared to a
recommended starting depth of >0.8 m for the SSF with a minimum of 0.5–0.7 m)
Maximum recommended filtration rate of the BSF is nearly 15 times greater than for the
SSF (1.1 m/h in contrast to a recommended ( 0.08–0.4m/h) (Fox et al., 1994)
BSF uses local material whereas SSF sand are mostly from a commercial source.
2. Key parameters of filter operation and their effects on filter
performance
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•
•
Enhanced particle straining due to bio layer formation
Improved depth filtration by slowing the filtration rate
Altered the surface properties of the filtration media.
3. Examine and compare e-coli removal from (bio sand filter-standard
(BSF-S), biosand iron coated.(MBSF)
4. different microorganisms (MS-2, E. coli and poliovirus) was passed
through columns containing sand modified by FeCl3 and AlCl3
Observation
• Present status
• Removal of turbidity by the BSF was not as high as reported for
conventional SSF (Sims and Slezak, 1991)
• MBSF showed a slightly higher effluent turbidity compared to BSF
(Mansoor M.A, Davra K,2011)
• Amount of water per charge and pause period are important
operating parameters for both BSF and MBSF (Baumgartner et al
,2007) (Elliott et al,2008)
• Microbial reductions could be increased by increasing the retention
time of water in the filter(Elliott et al,2008)
• MBSF always gave better performance in terms of bacteria removal
in comparison to BSF (Mansoor M.A, Davra K,2011)
• Ripening and biofilm development defy easy quantification based
on water volume and water quality charged to the filter per
day (Campos et al., 2002)
Possibility of improvement
• To improve removal efficiency Screening can be used before
filtration to remove suspended solid.
• Chlorination can be performed after filtration
• UV rays or solar disinfection can further improve the process.
Challenges and future scope
• Mechanisms of virus removal or inactivation in the BSF,
however, require further investigation
• Biofilm development defy easy quantification based on water
volume and water quality charged to the filter per day
• Organic matter and suspended solids interfere with the adsorption
of virus in filter media .The performance of biosand filter under this
situation requires investigation
Reference
• (1) Ahammed M. M., Davra K., Performance evaluation of biosand filter modified with iron oxide-coated sand
for household treatment of drinking water, J. desalination 276(2011) 287-293
• (2) American Public Health Association, Standards Methods for the Examination of Water and Wastewater, 20 th
ed. American Public Health Association/American Water Works Association/Water Pollution Control Federation,
Washington DC, USA, 1998.
• (3) Cromeans T., Sobsey M. D., Fields H. A., 1987, Development of a plaque assay for a cytopathic, rapidly
replicating isolate of hepatitis A virus, J. Med. Virol. 22, 45–56.
• (4) Elliott E. A., Stauber C. E., Koksal F., DiGiano F. A., M.D. Sobsey, Reductions of E. coli, echovirus type 12
and bacteriophages in an intermittently operated household-scale slow sand filter, J. Water research 42 (2008)
2662-2670
• (5) Fox K.R., Graham N.J.D., Collins M.R., 1994, Slow sand filtration today: an introductory review. In: Collins,
M.R., Graham, N.J.D. (Eds.), Slow Sand Filtration. American Water Works Association, Denver, CO, pp. 1–8.
• (6) Lukasik J., Cheng Y. F., Lu F., Tamplin M. and Farrah S. R., Removal of microorganism from water by
columns containing sand coated with ferric and aluminum hydroxide, J. Wat. Res. Vol. 33, No. 3, pp. 769-777,
1999.
• (7) Sims R., Slezak L., 1991, Slow sand filtration: present practice in the United States. In: Logsdon, G. (Ed.),
Slow Sand Filtration. American Society of Civil Engineers, New York, NY, pp. 1–18.
• (8) Sobsey M. D. and Jones B. L. (1979) Concentration of poliovirus from tap water using positively charged
microporous filters. Appl. Environ. Microbiol. 3, 588±595.
• (9) Sobsey M. D., Cromeans T., Hickey A. R. and Glass J. S. (1984) Effects of water quality on microporous filter
methods for enteric virus concentration. Water Sci. Technol. 17, 665±679.
• (10) US Environmental Protection Agency, 2001. Method 1602: malespecific (F+) and somatic coliphage in water
by single agar layer (SAL) procedure, Washington, DC, EPA 821-R-01-029.
• (11) US Environmental Protection Agency, 2002. Method 1604: total coliforms and Escherichia coli in water by
membrane filtration using a simultaneous detection technique (MI Medium), Washington, DC, EPA 821-R-02-024
• (12) World Health Organization (WHO), 2004, Water sanitation and hygiene links to health-facts and figures.
• (13) Stauber C.E., Elliott E.A., Koksal F., Ortiz G.M., DiGiano F.A., Sobsey M.D., Characterization of the biosand
filter for E. coli reductions from household drinking water under controlled laboratory and field use conditions,
Water Sci. Technol. 54 (2006) 1–7.
• (14) US Environmental Protection Agency, 2001. Method 1602: malespecific (F+) and somatic coliphage in water
by single agar layer (SAL) procedure, Washington, DC, EPA 821-R-01-029.
• (15) US Environmental Protection Agency, 2002. Method 1604: total coliforms and Escherichia coli in water by
membrane filtration using a simultaneous detection technique (MI Medium), Washington, DC, EPA 821-R-02-024
• (16) World Health Organization (WHO), 2004, Water sanitation and hygiene links to health-facts
• (17) Haarhoff, J., Cleasby, J.L., 1991. Biological and physical mechanisms in slow sand filtration. In: logsdon, G.
(Ed.), Slow Sand Filtration. American Society of Civil Engineers, New York.
• (18) Hijnen, W.A., Schijven, J.F., Bonne, P., Visser, A., Medema, G.J., 2004. Elimination of viruses, bacteria
and protozoan oocysts by slow sand filtration. Water Sci. Technol. 50 (1), 1542–1552.
• (19 Sagripanti, J.L., Routson, L.B., Lytle, C.D., 1993. Virus inactivation by copper or iron ions alone and in the
presence of peroxide. Applied and Environmental Microbiology 59, 4374e4376
• (20) Weber-Shirk, M.L., Dick, R.D., 1997. Biological mechanisms in slow sand filters. Journal of American Water
Works Association 89 (2), 72e83.
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