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The Effects Of Phosphate And Silicate Inhibitors On Surface Roughness And Copper Release In Water Distribution Systems, David Macnevin
The Effects Of Phosphate And Silicate Inhibitors On Surface Roughness And Copper Release In Water Distribution Systems, David Macnevin
Electronic Theses and Dissertations
The effects of corrosion inhibitors on water quality and the distribution system were studied. This dissertation investigates the effect of inhibitors on iron surface roughness, copper surface roughness, and copper release. Corrosion inhibitors included blended poly/ortho phosphate, sodium orthophosphate, zinc orthophosphate, and sodium silicate. These inhibitors were added to a blend of surface water, groundwater, and desalinated brackish water. Surface roughness of galvanized iron, unlined cast iron, lined cast iron, and polyvinyl chloride was measured using pipe coupons exposed for three months. Roughness of each pipe coupon was measured with an optical surface profiler before and after exposure to inhibitors. …
Impact Of Corrosion Inhibitor Blended Orthophosphate On Water Quality In Water Distribution Systems, Abdulrahman Alshehri
Impact Of Corrosion Inhibitor Blended Orthophosphate On Water Quality In Water Distribution Systems, Abdulrahman Alshehri
Electronic Theses and Dissertations
The impact of blended orthophosphate (BOP) inhibitor addition on the corrosion of iron, copper, and lead in drinking water distribution systems was studied under changing water quality environment. Release of iron, copper, and lead were monitored at varying inhibitor doses and changing blends of source waters (groundwater, surface water, and desalinated water). Solid corrosion products on pipe surfaces under BOP treatment were evaluated with surface characterization techniques. Performance of the BOP inhibitor was compared to other corrosion control strategies. Iron scales for iron and galvanized steel coupons incubated in different blended waters in the presence of BOP inhibitor were analyzed …
The Effect Of Free Chlorine And Chloramines On Lead Release In A Distribution System, Ferdinand Vasquez
The Effect Of Free Chlorine And Chloramines On Lead Release In A Distribution System, Ferdinand Vasquez
Electronic Theses and Dissertations
Total lead release in drinking water in the presence of free chlorine and chloramine residuals was investigated in field, laboratory and fundamental investigations for finished waters produced from ground (GW), surface (SW), saline (RO) and blended (B) sources. Field investigations found more total lead was released in the presence of chloramines than in the presence of free chlorine for RO and blended finished waters; however, there were no statistical differences in total lead release to finished GW and SW. Laboratory measurements of finished waters oxidation-reduction potential (ORP) were equivalent by source and were not affected by the addition of more …
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. …
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 …
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 …