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Water Quality Variations During Nitrification In Drinking Water Distribution Systems, David W. Webb
Water Quality Variations During Nitrification In Drinking Water Distribution Systems, David W. Webb
Electronic Theses and Dissertations
This thesis documents the relationship among the major water quality parameters during a nitrification episode. Nitrification unexpectedly occurred in a chloraminated pilot drinking water distribution system practicing with a 4.0 mg/L as Cl2 residual dosed at 4.5:1 Cl2:NH3-N. Surface, ground and sea water were treated and disinfected with monochloramines to produce finished water quality similar to regional utility water quality. PVC, galvanized, unlined cast iron and lined iron pipes were harvested from regional distribution systems and used to build eighteen pilot distribution systems (PDSs). The PDSs were operated at a 5-day hydraulic residence time (HRT) and ambient temperatures. As seasonal …
Nitrification Investigation And Modeling In The Chloraminated Drinking Water Distribution System, Suibing Liu
Nitrification Investigation And Modeling In The Chloraminated Drinking Water Distribution System, Suibing Liu
Electronic Theses and Dissertations
This dissertation consists of five papers concerning nitrification in chloraminated drinking water distribution systems in a one and a half year field study. Seven finished waters were produced from different treatment processes and distributed to eighteen pilot distribution systems (PDSs) that were made pipes taken from actual distribution systems. Unlined cast iron (UCI), galvanized steel (G), lined cast iron (LCI), and PVC pipes were used to build the PDSs. All finished waters were stabilized and chloraminated before entering the PDSs. This dissertation consists of five major parts. (1) System variations of nitrates, nitrites, DO, pH, alkalinity, temperature, chloramine residuals and …
Biostability In Drinking Water Distribution Systems Study At Pilot-Scale, Michael Le Puil
Biostability In Drinking Water Distribution Systems Study At Pilot-Scale, Michael Le Puil
Electronic Theses and Dissertations
Biostability and related issues (e.g. nitrification) were investigated for 18 months in 18 pilot distribution systems, under various water quality scenarios. This study specifically investigated the impact of steady-state water changes on HPC levels in chlorinated and chloraminated distribution systems. Chlorination was more effective than chloramination in reducing HPC levels (1-2 log difference). There was a rapid increase in HPC corresponding to the change in steady-state water quality, which was observed in all PDS. Modeling effort demonstrated that HPC levels reached a maximum within five days after water quality change and return to initial level ten days after the change. …