Limited studies have been conducted to evaluate synergistic benefits between disinfectants, although promise has been shown between ultraviolet (UV) light and chlorine-based disinfectants. This research aimed to determine drinking water quality factors that affect potential for enhanced removal of heterotrophic bacteria due to synergy between UV light and free chlorine. An additional goal was to determine the impact of pipe material on the formation of biofilm and the effectiveness of combined disinfection in controlling it. Annular reactors (ARs) containing polycarbonate or cast iron coupons were used to simulate typical drinking water distribution systems. Two experiments were conducted with untreated hard groundwater and groundwater treated with ion exchange to remove hardness, each comparing chorine alone to chlorine with UV pre-treatment. Results show that enhanced removal of heterotrophic plate count (HPC) bacteria existed with hard water when UV preceded chlorine, but synergistic benefits were not consistently observed. Under softened water conditions, no enhanced reduction or synergy was observed. Cast iron ARs supported biofilm HPC bacteria that were unaffected by any disinfection scheme regardless of source water, while bulk HPC bacteria were more resistant to disinfection in polycarbonate than cast iron ARs. Results indicate that disinfection synergy between UV and chlorine is limited in groundwater sources.
Skip Nav Destination
Article navigation
November 2013
This article was originally published in
Journal of Water Supply: Research and Technology-Aqua
Article Contents
Research Article|
August 27 2013
Effect of water hardness and pipe material on enhanced disinfection with UV light and chlorine
J. L. Rand;
1Ivan Curry School of Engineering, Acadia University, Wolfville, NS, Canada B4P 2R6
E-mail: [email protected]
Search for other works by this author on:
M. Sharafimasooleh;
M. Sharafimasooleh
2Department of Civil and Resource Engineering, Dalhousie University, Halifax, NS, Canada B3H 4R2
Search for other works by this author on:
M. E. Walsh
M. E. Walsh
2Department of Civil and Resource Engineering, Dalhousie University, Halifax, NS, Canada B3H 4R2
Search for other works by this author on:
Journal of Water Supply: Research and Technology-Aqua (2013) 62 (7): 426–432.
Article history
Received:
March 15 2013
Accepted:
June 25 2013
Citation
J. L. Rand, M. Sharafimasooleh, M. E. Walsh; Effect of water hardness and pipe material on enhanced disinfection with UV light and chlorine. Journal of Water Supply: Research and Technology-Aqua 1 November 2013; 62 (7): 426–432. doi: https://doi.org/10.2166/aqua.2013.060
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