Ozonation is used as an alternative disinfection process to chlorination but unfortunately has a potential of oxidizing bromide, a natural component of water sources, to bromate. Bromate is a possible carcinogen with a maximum contaminant level of 10 ppb. To understand bromate formation in full-scale systems, a comprehensive study was conducted at the Moorhead Water Treatment Plant (WTP). Bromide concentrations in source waters were monitored. Water samples from locations in the ozonation chambers were collected and analyzed for bromate and other parameters. Results showed that bromate formation was increased through increases in pH, bromide, and ozone dose during high temperatures and was decreased by increases in organics. The impact of the bromate influential parameters was minimized at low temperatures. To assist Moorhead WTP on developing bromate control strategies, a modeling approach was adopted to predict bromate formation at various operational conditions using temperature, pH, ozone dose, bromide, and TOC. / MWH Global, AWWA Scholarship / American Water Works Association (AWWA), Minnesota and North Dakota sections / North Dakota Water Resources Research Institute / Department of Civil Engineering, North Dakota State University

A recent study at the Moorhead water treatment plant (MWTP) determined that bromate formed during ozone disinfection and, at times, exceeded the maximum contaminant level (MCL) of 10 parts per billion (ppb) in the summer months. Operational data showed that bromate formation was directly related to raw water bromide concentration and control of the ozone system. This study was conducted with the purpose of developing and implementing operational strategies to minimize bromate formation in the MWTP. Several operational changes, including selection of source water based on bromide concentration and controlling ozone addition in a manner that reduces the ozone dose used to achieve disinfection, were implemented and were effective at minimizing bromate formation in the ozone chambers. The bromate concentration in the finished drinking water was significantly reduced and only a few samples contained greater than 10 ppb bromate. / Moorhead Public Service / American Water Works Association

In this study photoelectrocatalytic technology has been combined with fuel cell technology in an attempt to provide a stand alone water polishing device to be applied to the water purification industry. Tungsten trioxide was chosen as the photoelectrocatalyst to be applied to the fuel cell membrane electrode assembly (MEA). In this thesis two possible WO₃-based photoanodes were studied. Firstly a Nafion-loaded WO₃ photoanode utilising the state of the art proton conductor Nafion in the MEA. The second WO₃-based photoanode was synthesised by a sol-gel method with a view to being directly sintered onto a not yet developed solid state MEA containing a proton conductive glass. In both methods electrochemical studies were undertaken with both WO₃ based photoanodes deposited on fluorine doped tin oxide glass (FTO). The WO₃ catalysts were studied by X-ray diffraction, Raman spectroscopy, Nitrogen adsorption and UV-visible spectroscopy. Electrochemical studies included cyclic voltametry and linear sweep voltametry under illumination to ascertain the photocurrent densities of the photoanodes and hence their ability to degrade water borne contaminants. The underlying materials properties were explored as well as the nature of the deposition to gain insight into the mechanisms responsible for effective photoelectrocatalytic activity. The Nafion-loaded WO₃ was applied to a Nafion membrane based MEA and utilised in a photoelectrocatalytic fuel cell. This was studied for possible application under self sustaining conditions for application in the water industry.

The purpose of this research is to compare the performance for the water quality of two traditional water treatment plants (WTP) and three advanced water treatment plants (AWTP), and to investigate the treated drinking water in distribution systems in Kaohsiung area for promoting the consumers¡¦ self-confidence. Samples of the treated water from five major water supplies¡¦ WTP(noted numbers: WF1, WF2, WF3, WF4 and WF5) and the tap water at user¡¦s end were selected in planning of this work. It was the traditional WTP stage with treated drinking water and distribution systems in Kaohsiung area During 91 year to 92 year, so we conducted WF1 and WF2 of 8 times sampling and WF3, WF4 and WF5 for 2 times sampling at this stage. In and after 93 year, we conducted WF1, WF2, WF3, WF4 and WF5 of 8 times sampling from 93 year to 94year for the advanced WTP stage. The major tests related with the parameters of influencing operation condition included pH, odor (abbreviated as TON), total trihalomethane (abbreviated as THMs), haloacetic acids (abbreviated as HAAs), nitrogen (abbreviated as, NH3-N, hardness, total dissolved solid (abbreviated as TDS), alkalinity, total organic carbon (abbreviated as TOC), calcium ion, flavor profile analysis (abbreviated as FPA), and suspension observation in boiling with treated waters from two WTP , three AWTP and the tap water at user¡¦s end in a distribution system. It point out the better quality of treated water used the advanced water treatment plants than that of traditional water treatment plant. The items with improvement of water quality, including THMs, HAAs, hardness, TON, 2-MIB, TOC, alkinality and Ca ions concentration, is presented. Their efficiency for improvement are respectively 47%, 29%, 43%, 11%, 29%, 15%, 14% and 34%. The insignificant efficiency were concentrated at TDS, NH3-N, pH and FPA. Water quality of six items are fitted for the drinking water standard at present in Taiwan (such as: odor<3 TON; THMs<0.1 mg/L; NH3-N<0.1 mg/L; TDS< 600 mg/L; Hardness <400 mg as CaCO3/L; 6.0<pH <8.5). The HAAs is fit for water quality USEPA first stage water standard (HAAs<80 £gg/L). In the suspension observation in boiling experimentation, we cooperate with the experiment of suspension observation in boiling to do contrast with TDS and hardness experiment, which can find out, the treated water after the advanced procedure, the time with boiling increases, the condition of its suspended substance has great reduction. It show treated drinking water after the advanced WTP can huge improve the traditional WTP¡¦s white suspended substance or white material precipitate questions in the boiling. In the contour map for water quality , we found that Gushan District, Lingya District, Qianzhen District, Xiaogang District, Fongshan City and Daliao Shiang etc had higher concentration profile in the four season (included spring, summer, fall and winter ) and during two seasons (included raining and drying) in the water supplies systems. We hope the contour map can offer a clear information of conveyer system administrator of drinking water and let administrator know where areas have high concentration produced in water quality management planning, in order to having priority or effective solutions (included washing the pipeline, changing the pipeline, changing the water flow, etc.).

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 373-387). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 373-387). Also available on the Internet.

Thesis (MTech. degree inChemistry.)--Tshwane University of Technology, 2010. / Introduction: Since the establishment of relationships between BOD, COD and TOC in early 1980’s, total organic carbon (TOC) analysis has been the analytical backbone of many water treatment laboratories (Furlong et al. 1999). It is only a question of time before South Africa follows suite, if only to adhere to export legislation and requirements. The question is whether TOC is just another expensive analytical tool for policing effluent, or is TOC results valid criteria for monitoring pollution. Aim: The purpose of this project was to evaluate the determination of TOC as a management tool on a wastewater treatment plant (WWTP) and compare it to the chemical oxygen demand (COD) analysis traditionally applied. Experimental: Five sampling points throughout the wastewater treatment plant were evaluated. A possible comparison between TOC and COD was investigated. Sampling was done using an ISCO 3700 portable sampler at each individual sampling point. The samples were filtered and analysed for TOC in the laboratory using an ISCO EZ 3500 TOC analyser. COD analysis was done colorimetrically by using a Hach DR 2000 photometer. Both analyses were done according to standard methods for water and wastewater. Because the ISCO EZ 3500 TOC is an online instrument, it was evaluated at two of the wastewater treatment plant. Results: The analysis of TOC is a more rapid method than COD for the determination of organic load and thus has the potential for better early warning and pollution control management. The change in chemical composition of raw sewage made it difficult to find consistent correlation between COD and TOC results. However, it was found that an online TOC analyses was a practical alternative to COD for plant control, process management and monitoring of inflow and effluent flows in wastewater treatment plant. Conclusion: Limitations of TOC analysis must be considered and include practical problems due to the high content of suspended solids in raw sewage and activated sludge, as well as the partial oxidation of certain organic compounds by ultra-violet/persulphate digestion. Although COD analysis is chemically hazardous and time-consuming compared to TOC analysis, it is not likely that TOC will replace COD on the WWTP, due to historical data accumulation, practicality and people’s natural opposition to change. However, it is hoped that the results of this study will increase knowledge about TOC and be used for practical implementation where this technique has advantages over COD

Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1926. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed September 15, 2009) Includes bibliographical references and index.

Thesis (M.S.)--Wisconsin. / Includes bibliographical references (leaf 54).

Made available in DSpace on 2014-10-09T12:38:36Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:36Z (GMT). No. of bitstreams: 1 06057.pdf: 4829282 bytes, checksum: d92eb047d0390013a61d21a5e1144641 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP