Disinfection of Water and Wastewater Using Gamma Irradiation in Isfahan Water and Wastewater Treatment Plants

Document Type : Research Paper

Authors

1 Faculty Member of Environmental Health Eng., Faculty of Public Health, Shahrekord University of Medical Sciences, Shahrekord

2 Asist. Prof., Environment Research Center., Faculty of Public Health, Isfahan University of Medical Sciences, Isfahan

3 Prof., Environment Research Center., Faculty of Public Health, Isfahan University of Medical Sciences, Isfahan

4 Faculty Member of Medical Physics, Boushehr University of Medical Sciencs

5 B. A. of Microbiology, Environment Research Center, Isfahan University of Medical Sciences

Abstract

To investigate the effect of gamma irradiation on the disinfection of water and wastewater, water samples were collected from raw and filtered water and wastewater samples were taken from the effluent of the secondary sedimentation, polished effluent (1-day retention time), and also from filtered (rapid sand filter) effluent. The samples were irradiated with gamma collimated beam in a batch system using a Co-60 therapeutic gamma radiation machine with a radioactive source emission rate of 405.38CGy/min at different doses of 20-160 Gy and 80-240 Gy, respectively. The samples were analyzed before and after irradiation for total and fecal coliforms. It was observed that nearly 100% reduction was achieved in total and fecal coliforms in water samples treated with a dose of 160 Gy. Depending on effluent quality, disinfection efficiencies achieved using 240 Gy gamma irradiation for inactivation of total coliforms in wastewater samples were 83, 64, and 56 percent for filtered, clarified, and secondary effluents, respectively. The same values were nearly 81, 58, and 46 percent, respectively, for inactivation of fecal coliforms. At lower doses of 120-240Gy, the coliform bacteria were successfully inactivated. It was concluded that a linear correlation holds between the dose delivered and the inactivation of microorganisms, so that inactivation increases with increasing irradiation time.

Keywords

References

1- Tchobanglous, G., and Burton, F. (2003). Wastewater Engineering Treatment, disposal and reuse, 4th Ed., McGraw-Hill, Metcalf and Eddy Inc.,New York.
2- Al-Ani, M. Y., and Al-Khalidy, F. R. (2006). “Use of ionizing radiation technology for treating municipal wastewater.” Int. J. Environ. Res. Public Health, 3(4), 360-368.
3- Thompson, E. J., and Blatchley, R. E. (1999). “Toxicity effects of gamma irradiated wastewater effluents.”Wat. Res., 33 (9) 2053-2058,
4- William, R. H., Geoffrey S. L., and Hendee, E. G. (2005). Radiation therapy physics, John Wiley and Sons Inc. Publication,New York.
5- Clesceri, L. S., Greenberg, A. E., and Eaton, A. D. (2005). Standard methods for the examination of water and wastewater, 20th Ed., American Public Health Association, WEF., AWWA, Washington DC.
6- Knecht, A. M. (2001). Hazardous and radioactive waste treatment technologies handbook, 1st Ed., Idaho National Engineering and Environmental Laboratory,USA.
7- Taghipour, F. (2004). “Ultraviolet and ionizing radiation for microorganism inactivation.” Water Research, 38 (18), 3940-3948.
8- Swinwood, J. F., Waite, T. D., kruge, P. R., and Raso, S. M. (1994). “Radiation : Technologies for water treatment, A global prespective.” J. of the International Atomic Energy Agency, 36 (1), 5-11.
9- Behjat, A., Mozahheb, S. A., Khalili, M. B., Vakhshoor, B., Zareshaei, H., and Fallahzadeh, M. (2007). “Advanced oxidation treatment of drinking water and wastewater using light-energy electron beam irradiation.” J. of Water and Wastewater, 61, 60-68. (In Persian)
10- Gautam, S., Shah, M. R., Sabharwal, S., and Sharma, A. (2005). “Gamma irradiation of municipal sludge for safe disposal and agricultural use.” Wat. Res., 77 (5), 427-429.
11- Thompson, E. (1997). Gamma irradiation for disinfection of water and wastewater, Francis Pub.,Purdue University,Indiana.
12- Rawat, K. P., Sharma, A., and Rao, S. M. (1998). “Microbiological and physiochemical analysis of radiation disinfection municipal sewage.” Wat. Res., 32 (3) 737-740.
Journal of Water and Wastewater; Ab va Fazilab ( in persian )
Volume 21, Issue 4 - Serial Number 4
Serial number:76
January 2011
Pages 28-32

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