| dc.contributor.author | Rand, Jennie Leigh. | en_US |
| dc.date.accessioned | 2014-10-21T12:34:09Z | |
| dc.date.available | 2006 | |
| dc.date.issued | 2006 | en_US |
| dc.identifier.other | AAINR27650 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10222/54929 | |
| dc.description | In the treatment and distribution of drinking water, disinfection is a key step for inactivating microbial pathogens and controlling biofouling in pipe lines. Biofilm, which forms on pipe walls, leads to microbial regrowth, biocorrosion and headloss in distribution systems. Utilities depend on disinfection as a key step for the control of biofilm. Chlorine is traditionally the most widely used chemical disinfectant, however alternatives such as chlorine dioxide and chloramines are emerging, each showing benefits and drawbacks. Research has shown that by-products (DBPs) that are formed with these disinfectants can pose serious health threats. The result is new drinking water standards becoming stricter in the past few years. Ultraviolet light, which forms few DBPs and is more effective against chlorine-resistant pathogens, is a relatively new concept in drinking water treatment. It is being introduced as a viable disinfection option however does not provide residual protection for pipe systems. Utilities will often utilize primary and secondary disinfectants in combination in the treatment process for different reasons, and although this is a widely used practice little emphasis has been placed on the potential for synergistic benefits between disinfectants. | en_US |
| dc.description | There have been few studies published designed specifically to investigate synergy, especially using UV light for the treatment of drinking water. The motivation for this study was to investigate interactions between UV light and chlorine-based disinfectants and determine if synergy enhances removal of microbial pathogens in drinking water distribution systems. The main hypothesis of this work is that UV in combination with chlorine-based disinfectants forms an integrated disinfection process that enables an improved reduction strategy than when working as independent disinfection agents. Field studies and laboratory studies were designed to compare effectiveness of chlorine, chlorine dioxide and monochloramine with and without UV treatment. Long-term field studies incorporated distribution system simulation and looked at the possibility of lowering required chemical dosages when UV light was introduced into the treatment process, thereby lowering formation of DBPs. Work included utilizing UV light as a primary disinfectant prior to any chemical application and also as a secondary disinfectant following chemical disinfection. In addition, various water sources and climates were tested including groundwater, surface water and blended water in California, Florida, and Nova Scotia. Laboratory studies investigated potential for synergy in a controlled setting and also the effect of UV treatment on chemical residuals in a water stream. The conclusions drawn from these studies are able to give insight into integrated disinfection strategies and the associated benefits and drawbacks. | en_US |
| dc.description | Thesis (Ph.D.)--Dalhousie University (Canada), 2006. | en_US |
| dc.language | eng | en_US |
| dc.publisher | Dalhousie University | en_US |
| dc.publisher | | en_US |
| dc.subject | Engineering, Civil. | en_US |
| dc.subject | Engineering, Sanitary and Municipal. | en_US |
| dc.title | Integrated disinfection for mitigating microbial regrowth in drinking water distribution systems. | en_US |
| dc.type | text | en_US |
| dc.contributor.degree | Ph.D. | en_US |
