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1

Ali, Omar Feroze. "Dynamic chlorination of kraft pulp." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75877.

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Chlorination of kraft black spruce pulp was studied in a fixed bed reactor. Breakthrough curves of the reactant chlorine and the products TOC, chloride and methanol were measured. The flow residence time distribution was determined by performing a stimulus response tracer experiment preceding chlorination of each pulp pad. The chlorine and methanol break-through curves were well described by a parallel plug flow model and instantaneous chlorine-lignin and first order chlorine-carbohydrates reactions. The representation of the residence time distribution by plug flow through segregated channels rather than by axial dispersed plug flow was confirmed by the effect of operating variables on the residence time distribution and by comparison with theory and numerical predictions. The good representation of the actual flow by the parallel plug flow model can be explained by poor radial mixing and a relatively large scale of variation in radial velocity. The latter is a direct consequence of the large aspect ratio of pulp fibers and their associated tendency to flocculate. This also explains why the dispersion in pulp pads is larger than in beds of regular shaped particles which have the same equivalent diameter as pulp fibers.
Chlorine-lignin and methanol-lignin stoichiometries were determined as a function of operating conditions. The chlorine-lignin stoichiometry is a function of mean residence time and temperature, but not of chlorine feed concentration. The values of the chlorine-lignin stoichiometry are lower than found for corresponding batch chlorination of softwood pulps. The methanol-lignin stoichiometry is not influenced by any of the operating variables. The methanol concentration in the effluent can be used as an indicator for the completion of the chlorine-lignin reaction. Pulp properties such as lignin content, kappa number and viscosity were measured at the end of an experiment. Maximum delignification in any channel is obtained at chlorine breakthrough. Recycling of reconcentrated spent filtrate did not hinder delignification rates. The reciprocal intrinsic viscosity is proportional to the chlorine charge on pulp. Higher pulp viscosities are obtained at lower temperatures and mean residence times and at higher chlorine feed concentrations for the same chlorine charge on pulp. Viscosity protection agents like chlorine dioxide are effective in dynamic chlorination.
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2

ZOCATELLI, TAIANE FRACALOSSI. "TANTALUM PENTOXIDE CHLORINATION WITH TETRACHLORETHYLENE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36926@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
Processos de ustulação cloretante podem ser realizados de forma direta, utilizando o Cl2 como agente cloretante, ou através de agentes cloretantes alternativos. Neste contexto, compostos organoclorados são promissores, pois além de serem facilmente volatizados, já apresentam na mesma molécula o agente cloretante e redutor. O presente estudo teve como principal objetivo a avaliação quantitativa da cinética de cloração do pentóxido de tântalo com tetracloroetileno através dos modelos do núcleo não reagido (SC) e auto catalítico (AC). Tanto o material inicial, quanto o mesmo após o processo, bem como o produto sólido depositado na saída do reator foram caracterizados via DRX e MEV/EDS. Através de simulações termodinâmicas foi possível verificar a viabilidade de cloração de amostras puras de Ta2O5 com C2Cl4 diluído em atmosfera de N2 na faixa de temperatura entre 800 a 950 graus Celsius, sendo os principais cloretos gasosos formados, TaOCl3 e TaCl5. Verificou-se ainda a possível decomposição térmica do agente cloretante no caminho entre a entrada do reator e a amostra. Os resultados provenientes das caracterizações comprovaram as tendências apontadas pelas simulações termodinâmicas, comprovando a formação exclusiva de cloretos voláteis. No que diz respeito à modelagem cinética ambos os modelos permitiram o ajuste dos dados em nível quantitativo, sendo os valores de energia de ativação global iguais a 93,8 kJ/mol (SC) e 32 kJ/mol (AC). A comparação dos valores obtidos com dados da literatura sugere que o controle é de natureza química, sendo a decomposição do C2Cl4 na superfície das nanopartículas de Ta2O5, possivelmente, a etapa controladora.
Chlorination roasting can be carried out directly, using Cl2 as a chlorinating agent, or through alternative reagents. In this context, organochlorine compounds are promising, since besides being easily volatilized, they already present in the same molecule the chlorinating and reducing agents. The present study had as main objective the quantitative evaluation of the chlorination kinetics of tantalum pentoxide with tetrachlorethylene through the shrinking core (SC) and auto catalytic (AC) models. The initial material, as well as post-processed materials, and also the solid product deposited at the reactor s exit were characterized through DRX and MEV/EDS. By means of thermodynamic simulations, it was possible to verify the viability of pure Ta2O5 samples chlorination with C2Cl4 diluted in N2 in the temperature range of interest (800 - 950 Celsius Degree), thereby producing only gaseous chlorides, TaOCl3 and TaCl5. The possible C2Cl4 thermal decomposition in the path between the reactor inlet and sample was also identified. The characterization results were in accordance with the tendencies indicated by the thermodynamic simulations, proving the exclusive formation of volatile chlorides. With regard to the kinetic study, both tested models allowed quantitative adjustment of the conversion data, with overall activation energies equal to 93.8 kJ/mol (SC) and 32 kJ/mol (AC). The comparison of the values obtained with literature data suggests that the control is of chemical nature, the decomposition of C2Cl4 on the surface of the Ta2O5 nanoparticles being, possibly, the main control reaction step.
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3

Gao, Chengzhe. "Regioselective chlorination of cellulose esters." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/96548.

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Chemical modification of cellulose has been of growing interest, owing to the abundance and processing challenges of natural cellulose. To date, etherification and esterification are the most effective strategies to modify physicochemical properties of cellulose and append new functionalities. However, they typically require relatively harsh conditions, thus limiting introduction of new functional groups. An alternative strategy to synthesize novel cellulose derivatives is to append a good leaving group to cellulose backbone, followed by nucleophilic substitution reaction. Though tosylation and bromination of cellulose are frequently used, they have drawbacks such as chemo- and regioselectivity issues, high cost, and difficulty in purification. We have successfully developed a method to chemo- and regioselectively chlorinate cellulose esters using MsCl. Compared to bromination of cellulose typically used, this chlorination method has many advantages, including low cost of reagents and ease of separation. The chlorinated cellulose esters are useful intermediates for appending new functionalities by displacement reactions. We have synthesized a library of cellulose ester derivatives by this chlorination/nucleophilic substitution strategy, including cationic and anionic cellulose ester derivatives. These cellulose ester derivatives possess great potentialiii for various applications, including amorphous solid dispersion, tight junction opening, anionic drug delivery, and gas separation membranes.
MS
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4

Hwang, Bing-Fang. "Water chlorination and birth defects." Available to US Hopkins community, 2002. http://wwwlib.umi.com/dissertations/dlnow/3068171.

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5

Hassinger, Elaine. "Shock-Chlorination of Domestic Wells." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 1994. http://hdl.handle.net/10150/156938.

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1 pp.
Shock-chlorination is an effective way to disinfect your well and household plumbing. You should shock-chlorinate your well after repairing it, or, if a lab test shows there are coliform bacteria in the water. This publication explains how shock-chlorination works and the steps needed to use this treatment.
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6

Adipuri, Andrew Materials Science &amp Engineering Faculty of Science UNSW. "Chlorination of Titanium Oxycarbide and Oxycarbonitride." Publisher:University of New South Wales. Materials Science & Engineering, 2009. http://handle.unsw.edu.au/1959.4/44405.

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The project undertook a systematic study of chlorination of titanium oxycarbide and oxycarbonitride with the aim to develop further understanding of kinetics and mechanisms of the chlorination reactions. The project studied titania, ilmenite ores, and synthetic rutile reduced by carbon in argon and nitrogen and chlorinated at different temperatures, gas flow rates and compositions. Chlorination of titanium suboxides, iron and impurities in ilmenite was also examined. Chlorination of titanium oxycarbide Ti(O,C) or oxycarbonitride Ti(O,C,N) can be implemented at 200 to 400 deg.C, while the commercial chlorination process in the production of titanium metal or titania pigment requires 800 to 1100 deg.C. This makes chlorination of Ti(O,C) or Ti(O,C,N) an attractive technology in processing of titanium minerals. Chlorination reaction is strongly exothermal, which increased the sample temperature up to 200 deg.C above the furnace temperature. The chlorination of Ti(O,C) or Ti(O,C,N) was ignited at 150 deg.C to 200 deg.C depending on the sample composition. Their chlorination at 235 deg.C to 400 deg.C was close to completion in less than 30 min. The chlorination rate of titanium oxycarbide or oxycarbonitride increased with increasing gas flow rate. Sample composition had a significant effect on the extent of chlorination. The optimum results were obtained for titanium oxycarbide or oxycarbonitride produced with carbon to titania molar ratio of 2.5; these samples contained no detectable excess of carbon or unreduced titanium suboxides. In chlorination of reduced ilmenite ores and synthetic rutile, Ti(O,C) or Ti(O,C,N), metallic iron and Ti2O3 were chlorinated. The rate and extent of chlorination of titanium increased with increasing carbon to TiO2 ratio. Chlorination of Ti2O3 was slow relative to Ti(O,C) or Ti(O,C,N) and iron; chlorination of impurity oxides such as MgO, SiO2 and Al2O3 was not observed. The project also examined chlorination of Ti(O,C) or Ti(O,C,N) in ilmenite ore and synthetic rutile after removal of iron, which was achieved by aerated leaching of reduced samples in heated flask containing 0.37 M of ammonium chloride solution. Iron removal from the ilmenite ore or synthetic rutile resulted in higher rate and extent of chlorination of titanium oxycarbide or oxycarbonitride.
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7

Izimas, M. "Selective control of chlorination of phenols." Thesis, Swansea University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637380.

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The chlorination of meta-cresol by sulfuryl chloride in the presence of different sulfur containing catalysts was studied. In homogeneous conditions, the chlorination of meta-cresol was catalysed by dialkyl sulfides and dithia-alkenes. The influence of various reaction parameters was investigated. The dithia-alkanes were not commercially available and needed to be synthesised prior to their use. A new method for the synthesis of unsymmetrical dithia-alkanes was developed. The chlorination of meta-cresol using di-iso-propyl sulfide and di-n-butyl sulfide was scaled up and the reaction mixture separated by fractional distillation. The catalyst was recovered and reused. 5,18-Dithiadocosane, a successful catalyst for the chlorination of meta-cresol, was also tested as catalyst for the chlorination of phenol, anisole, meta-xylenol, toluene and naphthalene. In heterogeneous conditions, the chlorination of meta-cresol was catalysed by polymers containing thia-alkyl groups. The synthesis of the polymers by modification of bromopolystyrene and Merrifield resin was studied and a new method was developed to avoid crosslinking. A polythia-alkane was also synthesised from 1,6-hexanedithiol and 1,8-dibromo-octane.
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8

Davis, Gareth Michael. "Mathematical modelling of swimming pool chlorination." Thesis, University of Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402341.

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9

Earls, Dru. "Alternative to chlorination of cake flour /." Search for this dissertation online, 2003. http://wwwlib.umi.com/cr/ksu/main.

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10

D'Cunha, Cassian. "Theoretical Study of Chloroperoxidase Catalyzed Chlorination of beta-Cyclopentanedione and Role of Water in the Chlorination Mechanism." FIU Digital Commons, 2011. http://digitalcommons.fiu.edu/etd/515.

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Chloroperoxidase (CPO) is a potential biocatalyst for use in asymmetric synthesis. The mechanisms of CPO catalysis are therefore of interest. The halogenation reaction, one of several chemical reactions that CPO catalyzes, is not fully understood and is the subject of this dissertation. The mechanism by which CPO catalyzes halogenation is disputed. It has been postulated that halogenation of substrates occurs at the active site. Alternatively, it has been proposed that hypochlorous acid, produced at the active site via oxidation of chloride, is released prior to reaction, so that halogenation occurs in solution. The free-solution mechanism is supported by the observation that halogenation of most substrates often occurs non-stereospecifically. On the other hand, the enzyme-bound mechanism is supported by the observation that some large substrates undergo halogenation stereospecifically. The major purpose of this research is to compare chlorination of the substrate beta-cyclopentanedione in the two environments. One study was of the reaction with limited hydration because such a level of hydration is typical of the active site. For this work, a purely quantum mechanical approach was used. To model the aqueous environment, the limited hydration environment approach is not appropriate. Instead, reaction precursor conformations were obtained from a solvated molecular dynamics simulation, and reaction of potentially reactive molecular encounters was modeled with a hybrid quantum mechanical/molecular mechanical approach. Extensive work developing parameters for small molecules was pre-requisite for the molecular dynamics simulation. It is observed that a limited and optimized (active-site-like) hydration environment leads to a lower energetic barrier than the fully solvated model representative of the aqueous environment at room temperature, suggesting that the stable water network near the active site is likely to facilitate the chlorination mechanism. The influence of the solvent environment on the reaction barrier is critical. It is observed that stabilization of the catalytic water by other solvent molecules lowers the barrier for keto-enol tautomerization. Placement of water molecules is more important than the number of water molecules in such studies. The fully-solvated model demonstrates that reaction proceeds when the instantaneous dynamical water environment is close to optimal for stabilizing the transition state.
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11

Vali, nia Salar. "Chlorination of Organic Material in Agricultural Soil." Thesis, The Tema Institute, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-19649.

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Chlorine is an essential building block in the environment and can be found in most places. Chlorine participates in a complex biogeochemical cycle and has been discussed for many years and it is well documented that natural chlorination of organic compound takes place in many parts of the ecosystem. Chlorine can be inorganic (Clin) and organically bound (Clorg). Previous studies have shown that the transformation of Clin to Clorg is connected with the amount of organic matter and the microbial activity in the soil. So far, studies have been focused on forest soil and there is a need for analysing the natural chlorination in other soil types. The aim of this study was to provide chlorination rates in agricultural soil which does not weem to have been done previously. Three common agricultural soils experiencing different agricultural practice and different cropping systems were incubated with Na36Cl at 20o C in a 56 days radiotracer experiment. The results show that a chlorination of 36Clin to 36Clorg in agricultural soil occurred and the Clorg levels increased over time. The chlorination rates ranged from 0,040 to 0,063 μg Cl g dry weight soil-1 d1. This was 10-fold lower than rates previously measured in coniferous forest soil. However, when expressed as μg Cl g dry weight organic carbon-1 d-1, rates in the agricultural soil was only slightly (at the most 2-fold) lower than in coniferous forest. This study contributes with new knowledge of natural chlorination rates in agricultural soil and gives further evidence that the natural chlorination can be connected to the amount of organic matter in the soil.

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12

Burns, Barbara J. "A kinetic study of medium consistency chlorination." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/5803.

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13

Farr, Gary Derek. "Chlorination effluent recycle in kraft pulp bleaching." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/29938.

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When performed at an industrial scale, kraft pulp bleaching commonly utilizes recycled chlorination effluent for brown stock dilution. Much of the information regarding this practice pertains to pulp quality. Some of the previous research done in this field failed to separate its effect from the effect of countercurrent effluent recycle for pulp washing. In addition, there are some shortcomings of the batch techniques that have been used to simulate effluent recycle in the laboratory. Thus little is known about the effect of this practice on effluent quality. Accordingly, the objective of this research project was to determine the effect of chlorination effluent recycle for brown stock dilution on the quality of kraft pulp bleaching effluent. Chlorination effluent recycle was investigated in conjunction with the variables of multiple, mode, and chlorine dioxide substitution. Effluent quality was characterized in terms of toxicity, total chlorinated organic compounds, and chlorate. Pulp quality was also measured. A full 2⁴ factorial design was carried out with 24 bleaching runs. The experimentation was performed in the laboratory using a two-stage (CE) bleaching sequence. A specially designed continuous laboratory-scale pulp chlorination apparatus, which was operated with an unbleached pulp throughput of 6 odg/min, was used to execute the first stage. By producing sufficient quantities of effluent at steady state in a short period of time, this apparatus enabled the efficacious use of trout bioassays. The second stage was performed on a batch basis. Results from the laboratory experiments were compared to those from an industrial-scale bleach plant. The chlorination stage toxic emission factor for rainbow trout decreased by 314 m³/adt as the level of recycle was increased from 4.5 to 22.5 m³/adt. The effects of multiple, mode, and substitution were also significant. Effluents from the extraction stage were much less toxic than those from the chlorination stage. The first stage toxic emission factors for trout and luminescent marine bacteria were not correlated. In addition, the concentration of organochlorine compounds and the number of toxic units were not correlated. A novel method for determining the toxic emission factor from median lethal time data was also developed. Recycle had no significant effect on the total production of chlorinated organic compounds, which were quantified together in terms of AOX. A regression equation, which includes the effects of multiple and mode as well as the interaction between multiple and substitution, was formulated for the AOX results. Recycle had no significant effect on the production of chlorate. A regression equation, which includes the variables of substitution and mode, was formulated for the chlorate results. A hypothesis, which involves the reactions of chlorine and chlorine dioxide with the phenolic hydroxyl groups of lignin, was developed to explain several characteristics of this equation. Recycle also had no effect on pulp quality, which was measured after the extraction stage with the kappa number and the viscosity. Mode and multiple were the only factors that significantly affected the kappa number. A hypothesis, which involves the reactions of chlorine and chlorine dioxide with dissolved organic material in the chlorination stage, was developed to explain the effect of mode on delignification. None of the variables had a significant effect on the viscosity.
Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate
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14

Broers, Teresa. "Abruptio placentae and chlorination disinfection by-products." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63274.pdf.

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15

Soleiman, Moe Karbal. "Catalytic chlorination of alpha-alumina with Cl." Thesis, Connect to this title online; UW restricted, 1986. http://hdl.handle.net/1773/15501.

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16

Gilmore, Laurie Ann. "Chlorination of synthetic dyes and synthetic brighteners." Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/20794.

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17

Misra, Girish. "Biotransformation of monoterpenes and their chlorination products." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/20842.

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18

Melhuish, M. W. "Nitration and chlorination of deactivated aromatic compounds." Thesis, University of Exeter, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379462.

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19

Ebbett, Virginia Rose. "The Chlorination of Triclosan: A Kinetic Study." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/43524.

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Triclosan, 5-chloro-2-(2,4 dichlorophenoxy)phenol, is an anti-microbial additive in a plethora of Pharmaceutical and Personal Care Products (PPCPs) including, toothpastes, hand creams and soaps, and acne creams. Because many triclosan containing products are topical solutions that are readily washed down the drain, significant quantities of triclosan can be introduced to wastewater treatment systems and eventually, to surface waters. Consequently, triclosan has become a contaminant of concern. The reactions between triclosan and free chlorine have been examined previously; however, no kinetic data for these reactions have been reported for conditions typical of drinking water treatment. This investigation focused specifically on the kinetics of the triclosan and free available chlorine (FAC) reactions under drinking water treatment conditions. Triclosan readily reacted with free chlorine via a second-order reaction (first order with respect to each species). No significant temperature dependency was observed from 8 to 25 °C. The reaction stoichiometry was determined to be 1:1 (triclosan oxidized per free chlorine reduced and did not vary over the pH range examined (pH 4-12). However, the reaction rate coefficients exhibited a significant pH dependency. A model that incorporates the rate coefficients for the reactions between HOCl and both neutral and anionic forms of triclosan was generated to fit the experimental data. The anionic free chlorine species hypochlorite (OCl-) was determined to play an insignificant role in the overall rate of reaction, and therefore, only the reactions involving HOCl were incorporated into the model. Additionally, a hypothesized reaction mechanism was tentatively shown to fit the collected data and its strong pH dependency.
Master of Science
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20

Ndula, Bungu Peter. "Fluidised-bed chlorination of oxidised titania slag." Diss., University of Pretoria, 2004. http://hdl.handle.net/2263/29501.

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Please read the abstract in the section, 00front of this document
Dissertation (MSc (Metallurgy))--University of Pretoria, 2004.
Materials Science and Metallurgical Engineering
MSc
unrestricted
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21

Dungeni, M., der Merwe RR van, and MNB Momba. "Abundance of pathogenic bacteria and viral indicators in chlorinated effluents produced by four wastewater treatment plants in the Gauteng Province, South Africa." Water SA, 2010. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001209.

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Abstract The failure of South African wastewater treatment plants to produce effluents of a high microbiological quality is a matter of great concern in terms of the pollution of water resources. This study aimed at assessing the effectiveness of 4 wastewater treatment plants in the Gauteng Province, namely the Zeekoegat, Baviaanspoort, Rayton and Refilwe Water Care Works (WCW), in the removal of pathogenic bacteria and viral indicators. Also taken into consideration were free chlorine concentrations and turbidity levels, which were measured using standard methods. Conventional methods and/or polymerase chain reaction (PCR) techniques were used to detect and identify pathogenic bacteria and coliphages. The turbidity ranged from 2.39 to 62.40 NTU and the concentrations of free chlorine ranged from 0.03 to1.60 mg∙ℓ-1 for all plants. Despite high free chlorine residual concentrations in treated effluents, the survival and occurrence of Escherichia coli, Salmonella typhimurium and Vibrio cholerae were significantly higher at Baviaanspoort (100%, 88.2% and 35.3%), Refilwe (87.5%, 59.4% and 21.9%) and Rayton (75%, 38.2% and 9.4%) compared to Zeekoegat, which only showed the survival of E. coli, at a much lower occurrence rate of 8.8%. Somatic and F-RNA coliphages were removed at 15.57 % and 13.96% for Baviaanspoort, 11.62% and 22.42% for Refilwe, 25% and 32.10% for Rayton, and 40.41% and 52.57% for Zeekoegat WCW. Significant correlations were found between pathogenic bacteria and coliphages at all plants (r = 0.765 for Baviaanspoort, r = 0.904 for Zeekoegat, r = 0.680 for Refilwe, r = 0.796 or the Rayton WCW, p < 0.01). A combination of sedimentation, rapid sand filtration and chlorination processes was found to be a major prerequisite for the reduction of turbidity levels and viral indicators and the successful removal of pathogenic bacteria in the Zeekoegat WCW. This study therefore suggests an upgrading of the wastwater treatment plants by including processes such as rapid sand filtration and UV disinfection, which have proved to be effective in the removal and inactivation of pathogenic bacteria and viruses.
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22

Gustavsson, Malin. "Chlorination of organic material in different soil types." Thesis, Linköpings universitet, Tema vatten i natur och samhälle, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-77786.

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Research has shown that formation of chlorinated organic matter occurs naturally and that organic chlorine is as abundant as the chloride ion in organic soils. A large number of organisms are known to convert inorganic chloride (Clin) to organic chlorine (Clorg) (e.g. bacteria, lichen, fungi and algae) and some enzymes associated to these organisms are capable of chlorinating soil organic matter. The aim with the study was to compare organic matter chlorination rates in soils from several different locations dominated by either coniferous forest or pasture. Soil from eight samples sites in the southern of Sweden were incubated at 20°C with addition of 36Clin in a 138 days long radiotracer experiment. The results show that transformation of 36Clin to 36Clorg occurred and that the amounts of 36Clorg increased over time. The chlorination rate was higher in the samples from coniferous forest than in samples containing pasture soil, where the specific chlorination rate was 3-4 times smaller. This study contributes new information about chlorination in various soil types and soil from different locations in southern central Sweden. The similarity between the chlorination rates measured in coniferous forest soils so far indicate that up scaling to regional estimates may be less problematic than expected.
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Palmer, Fiona Lorraine. "Photocatalysis of aquatic humic substances prior to chlorination." Thesis, University of Ulster, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263245.

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Forsyth, S. R. "Chlorination of aromatic compounds by two phase electrolysis." Thesis, University of Southampton, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377797.

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How, Zuo Tong. "Reaction pathways in the chlorination of amino acids." Thesis, Curtin University, 2016. http://hdl.handle.net/20.500.11937/1036.

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Chlorination is one of the most widely used disinfection technique in drinking water treatment. However, during chlorination, the chlorine can also reacted with organic matter in the water to produce potentially harmful and odorous by-products. This Thesis investigated the reaction and formation pathways of these potentially harmful and odorous by products from the reaction between chlorine and amino acids and therefore aid in the prevention of the formation of these by-products.
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Ni, Yonghao. "Mechanism and kinetics of demethylation during kraft pulp chlorination." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61967.

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27

Kennedy, Mark William. "Chlorination of magnesium carbonate in a stirred tank reactor." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=24061.

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A study was conducted on the reaction of solid MgO formed from magnesite (MgCO$ sb3),$ with Cl$ sb2$ and CO gas, in a stirred tank reactor containing a liquid bath of MgCl$ sb2.$ The reaction rate was found to be controlled by CO mass transfer from the gas to the liquid phase and was zero order with respect to the concentration of MgO. At temperatures from 743 to $824 sp circ$C, the reaction rate exhibited an activation energy of 80 kJ/mol, which is typical of a diffusion controlled reaction.
The chlorinaton rate was effected by both temperature and CO/Cl$ sb2$ ratio and estimates of the optimum conditions were obtained: temperature $(856.6 sp circ$C) and ratio of CO/Cl$ sb2$ (1.24). The addition of an inert gas (N$ sb2)$ to the reagent mixture was found to decrease the reaction rate. Iron was found to have a negligible effect on reaction rate at the levels tested (up to 560 P.P.M.).
For those experiments conducted at $ rm 820 sp circ C pm 5 sp circ C,$ an overall correlation was obtained which related the MgO reaction rate, with impeller power (kW/m$ sp3),$ superficial gas velocity (cm/s) and the partial pressure of CO (atm.): rm Rate = 0.609 (P sb{g}/V sb1) sp{0.35} (v sb{s}) sp{0.64} (P sb{CO}) sp{1.14}, (kgmol/m sp3/h) eqno lbrack 55 rbrack. ixing and gas dispersion characteristics were defined for the specific impeller/tank geometry used in these experiments.
Using the results presented here, it would be possible to estimate the size and number of commercial stirred tank chlorination reactors, which would be required to produce any specified quantity of magnesium, starting from magnesite, with an accuracy of $ pm$44%, with 95% confidence.
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28

Peringer, Elvira Theresia. "Oxidative chlorination of methane over LaCl 3 -based catalysts." kostenfrei, 2008. http://mediatum2.ub.tum.de/doc/657141/657141.pdf.

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29

Oliveira, Luciana C. "Gas-phase surface oxidation and chlorination of carbon nanotubes /." Online version of thesis, 2009. http://hdl.handle.net/1850/10931.

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30

Thompson, Ina Sharon. "Optimisation of sodium hypochlorite dosing at Wylfa Power Station : an experimental study with Mytilus edulis." Thesis, Bangor University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263175.

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31

Будьоний, Олександр Петрович, Александр Петрович Буденный, Oleksandr Petrovych Budonyi, and В. С. Кохана. "Ультрафіолетове знезараження як альтернатива використанню хлорування." Thesis, Видавництво СумДУ, 2012. http://essuir.sumdu.edu.ua/handle/123456789/25605.

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32

Jansson, Stina. "Thermal formation and chlorination of dioxins and dioxin-like compounds." Doctoral thesis, Umeå universitet, Kemi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1881.

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This thesis contributes to an increased understanding of the formation of dioxins and dioxin-like compounds in combustion processes. Although emissions to air from waste incineration facilities have been greatly reduced by the use of efficient air pollution control measures, the resulting residues (ashes and filters) are highly toxic and are classified as hazardous waste. The main objective of the work underlying this thesis was to elucidate the formation and chlorination pathways of dioxins and dioxin-like compounds in waste combustion flue gases in the temperature range 640-200°C in a representative, well-controlled laboratory-scale reactor using artificial municipal solid waste. This could contribute to the reduction of harmful emissions to air and also reduce the toxicity of waste incineration residues, thus reducing or even eliminating the need for costly and potentially hazardous after-treatment. A comparison of four different quenching profiles showed that the formation of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) was rapid and mainly occurred in the 640-400°C temperature region, with high dependency on sufficient residence time within a specific temperature region. Prolonged residence time at high temperatures (450/460°C) reduced the PCDD yields, even at lower temperatures along the post-combustion zone. PCDD, PCDF and PCN (polychlorinated naphthalene) isomer distribution patterns indicated contributions from chlorophenol condensation as well as chlorination reactions for all three classes of compounds. The formation of PCDDs was largely influenced by chlorophenol condensation and to some extent by chlorination reactions. For the PCDFs, chlorine substitution adjacent to the oxygen bridges was unfavoured, as demonstrated by the notably lower abundance of 1,9-substituted congeners. This was supported by bidirectional orthogonal partial least squares (O2PLS) modelling. The variable with the greatest influence on the distribution of PCDD congeners was the relative free energy (RΔGf). The O2PLS models displayed distinct clusters, dividing most of the homologues into two or three sub-groups of congeners which seemed to correspond to the probability of origination from chlorophenol condensation. The effects of injection of aromatic structures into the flue gas differed for each class of compounds. Injection of naphthalene increased the formation of monochlorinated naphthalene but the remaining homologues appeared to be unaffected. This was probably due to insufficient residence time at temperatures necessary for further chlorination. Injected dibenzo-p-dioxin was decomposed, chlorinated and re-condensated into PCDDs and PCDFs, whereas injection of dibenzofuran and fluorene reduced the PCDD levels in the flue gas.
Denna avhandling fokuserar på olika aspekter som kan bidra till en ökad förståelse av bildning av dioxiner och dioxin-lika föreningar i förbränningsprocesser. Även om utsläppen till luft från sopförbränningsanläggningar har minskat kraftigt tack vare effektiva rökgasreningsmetoder, så återstår problemet med mycket giftiga rökgasreningsprodukter (askor och filter), vilka klassificeras som farligt avfall. Det huvudsakliga syftet med arbetet bakom denna avhandling var att klarlägga bildnings- och kloreringsvägarna för dioxiner och dioxin-lika föreningar i temperaturintervallet 640-200°C i rökgaser från sopförbränning. Detta kan möjliggöra lösningar för ytterligare emissionsminskningar och en avgiftning av biprodukterna från avfallsförbränning, vilket minskar eller till och med eliminerar behovet av kostsam och riskfylld efterbehandling. Realistiska och välkontrollerade försök har utförts i en lab-skalereaktor där en artificiell hushållssopa har förbränts. En jämförelse av fyra olika temperatur- och uppehållstidsprofiler visade att bildning av polyklorerade dibenso-p-dioxiner (PCDD) och dibensofuraner (PCDF) sker snabbt och huvudsakligen inom temperaturintervallet 640-400°C. Bildningen var starkt beroende av en tillräckligt lång uppehållstid inom ett visst temperaturområde. En förlängd uppehållstid vid höga temperaturer (>450°C) resulterade i minskade halter av PCDD, vilka förhöll sig låga även senare i efterförbränningszonen. Isomermönstren av PCDD, PCDF och PCN (polyklorerade naftalener) visade alla tecken på att härröra från både klorfenolkondensation och kloreringsreaktioner. PCDD-mönstret visade tydliga indikationer på bildning från klorfenoler, och till mindre grad bildning via klorering. För PCDF var klorsubstitution i positioner angränsande till syrebryggan missgynnad, vilket bekräftades av multivariat modellering (O2PLS). Den variabel som starkast påverkade bildningen av PCDD var relativa fria energin (RΔGf). Modellerna visade på en distinkt gruppering av PCDD- och PCDF-kongenerna i två eller tre grupper för varje kloreringsgrad, och föreslås vara relaterad till sannolikheten för respektive kongen att bildas via klorfenolkondensation. Injektion av aromatiska kolstrukturer i rökgaskanalen gav upphov till skilda effekter. Injektion av naftalen ökade bildningen av monoklorerad naftalen medan resterande homologer inte verkade påverkas, sannolikt på grund av för kort uppehållstid för ytterligare klorering. Dibenso-p-dioxin spjälkades sannolikt till fenoliska fragment som klorerades och sedan återkondenserades till PCDD och PCDF, medan dibensofuran och fluoren kraftigt reducerade PCDD-koncentrationerna.
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33

Iszatt, Nina. "Exposure to chlorination disinfection by-products and adverse reproductive outcomes." Thesis, Imperial College London, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538676.

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34

Tee, Kim Siong James. "Separation of zinc and copper from steel by oxy-chlorination." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624482.

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35

CLINTON, CAROL. "Kinetics of Chlorination of the Pesticide Aldicarb in Drinking Water." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1218732380.

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36

Sayers, Rachel Marie. "THE SYNTHESIS, REDUCTION, AND CHLORINATION OF 5-ALKOXY-2,3-DIPHENYLTEREPHTHALATES." Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1309375974.

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37

Williams, Des. "The selective chlorination of phenols using novel thiapolymers as catalysts." Thesis, Swansea University, 2006. https://cronfa.swan.ac.uk/Record/cronfa42654.

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Extensive work on enhancing the regioselectivity of electrophilic aromatic substitution reactions has been conducted at the Centre for Clean Chemistry, University of Wales Swansea. As a continuation of that work, this project involves the development of regioselective methods for the chlorination of phenols. Previous results conducted at the Centre for Clean Chemistry have shown that polythiaalkanes behave as highly selective catalysts for the chlorination of phenols with sulfuryl chloride. The work reported in this thesis involves the syntheses of numerous novel thiapolymers, containing branched chains, cyclic aliphatic rings and aromatic rings. These novel polymeric materials were tested as catalysts for the chlorination of phenol, o-cresol, m-cresol and m-xylenol. The first chapter gives an extensive introduction to aspects of the selective chlorination of phenols and a brief introduction to green chemistry and polymer synthesis. The second chapter reports the development of synthetic routes to some novel branched thiaalkanes from secondary dibromides. The synthesised novel branched thiapolymers were shown to be, above all, excellent selective catalysts for the chlorination of m-xylenol. The third chapter reports the synthesis of branched polymers and cyclic tetrahydrothiopyrans from methyl substituted 1,5-dibromopentanes. The branched polymeric materials synthesised were shown to behave as mediocre catalysts for the chlorination of phenols. However, the cyclic sulfides synthesised were shown to be excellent selective catalyst for the chlorination of o-cresol and also good selective catalysts for the chlorination of phenol and w-cresol. The fourth chapter reports the syntheses of thiapolymers containing cyclic aliphatic and aromatic rings. The novel cyclic aliphatic containing thiapolymers proved to be very effective selective catalysts for the chlorination of phenols with excellent results for the chlorination of o-cresol, and good results for the chlorination of w-cresol and w-xylenol obtained. Some of the novel aromatic containing polymers were also shown to be selective catalysts for the chlorination of o-cresol.
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38

Piety, Charles Andrew. "Kinetic and mechanistic studies of reactions of atomic chlorine with haloalkanes." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/27057.

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39

Taylor, J. M. "A study of the reaction of N-chloroamines with electron-rich aromatic compounds." Thesis, University of York, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379028.

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40

Pugliese, Sebastian C. "Kinetics and mass transfer in the chlorination of draft pulp fibers." Available online, Georgia Institute of Technology, 2005, 1988. http://etd.gatech.edu/theses/available/ipstetd-1040/.

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41

Pugliese, Sebastian C. III. "Kinetics and mass transfer in the chlorination of draft pulp fibers." Diss., Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/7046.

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42

Noack, Holger. "Biomimetic Iron Complexes involved in Oxygenation and Chlorination : A Theoretical Study." Doctoral thesis, Stockholms universitet, Fysikum, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-38197.

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Biomimetic chemistry is directed towards the simulation of enzymatic reactivity with synthetic analogues. In this thesis a quantum chemical method has been employed to study the mechanism of highly reactive iron-oxo complexes involved in oxygenation and chlorination of organic substrates. The aim of this research is to gain greater understanding for the reactivity paradigm of the iron-oxo group. One reaction deals with the conversion of cyclohexane into adipic acid, a key chemical in industrial chemistry, catalyzed by an iron(II)-porphyrin complex in the presence of dioxygen. This process constitutes a ’green’ alternative to conventional adipic acid production, and is thus of great interest to synthetic chemistry. Another reaction investigated herein regards the selective chlorination observed for a new group of non-heme iron enzymes. With help of theoretical modeling it was possible to propose a mechanism that explains the observed selectivity. It is furthermore demonstrated how a biomimetic iron complex simulates the enzymatic reactivity by a different mechanism. Other topics covered in this thesis regard the structure-reactivity relationship of a binuclear iron complex and the intradiol C-C bond cleavage of catechol catalyzed by an iron(III) complex.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Submitted. Paper 2: Accepted. Paper 3: Submitted.
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43

Lu, Junhe. "Fundamental studies of the halogenation of phenolic compounds during water chlorination /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/10197.

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44

McKeer, L. C. "A study of the chlorination of aromatic compounds with N-chloroamines." Thesis, University of York, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370740.

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45

Montoya-Pachongo, Carolina. "Disinfection by-product formation from biofilm chlorination in drinking water pipes." Thesis, University of Leeds, 2018. http://etheses.whiterose.ac.uk/19697/.

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Biofilms in drinking water distribution networks (DWDNs) are recognized as potential pathogen reservoirs. Recent experiments have found that biofilm can also act as precursors for the formation of disinfection by-products (DBPs). This project aimed to better understand the impact of the presence of biofilms and improve prediction of DBPs in DWDNs. To study the microbial significance of biofilms in water pipes, bacterial communities in biofilm and bulk water were identified in a DWDN in a tropical climate country. Drinking water and biofilms were characterised by physico-chemical parameters. Relationships between biotic, physico-chemical parameters and engineered factors (i.e., pipe age, material and diameter; and water age) were explored by the application of statistical tests. Additionally, improvement of DBP prediction in DWDNs was approached by modelling the role of biofilms as DBP precursors. Two models for predicting DBP formation potentials were developed from chlorination of cells and extracellular polymeric substances. The first model corresponded to stagnant conditions and a second more complex model was produced for transitional and turbulent flow. The models were implemented in the software COMSOL Multiphysics 5.2a and sensitivity analysis was carried out to screen the parameters influence on the response variables. Field-work assessment allowed determining that biofilms are richer habitats than bulk water. Pipe age, pipe material, water age, free chlorine, pH and temperature can be key to the composition of bacterial communities. Model simulations suggested that the important DBP exposure is related to dichloroacetronitrile, stagnant bulk, and slow flow. The microbial and chemical significance of biofilms is important in the context of climate change and developing countries because water managers can face multiple challenges under these conditions. Alterations of raw water properties, increasing occurrence of extreme weather events and poor capacity to mitigate such events may rise the chemical and microbiological risk associated to biofilms in DWDNs in tropical countries.
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46

ATGIN, REFET SINEM. "Modeling Vulnerability and Effectiveness of Chlorination in Drinking Water Distribution Systems." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1218826412.

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47

Marra, John Edward. "The behavior of silicon-based ceramics in mixed oxidation/chlorination environments /." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487327695624238.

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48

Gang, Dianchen. "Modeling of THM and HAA formation in Missouri waters upon chlorination /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3025619.

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49

Hassan, Ghanim. "Minimizing bacterial biofilm in water using froth flotation and shock chlorination." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/9723/.

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Microorganisms in potable water systems are either present in the planktonic “floating stage”, or attached to surfaces, usually as biofilm. Many hygienic and economic problems are attributed to this phenomenon. Through the last seven or so decades many trials were made to overcome biofilm problems. Unfortunately, biofilm prevention stills a premature field of science. Therefore, serious solutions with new horizons are needed. The objective of this study is to provide a water distribution system which is free of microorganisms, both in the planktonic and biofilm stages, and biocides. The two components are interactive; biofilm formation is stimulated by the presence of low (residual) levels of biocides whereas removing the bacteria results in less or no biocide being needed. The first part of the research investigates the use of chemical free froth flotation to remove microorganisms. Bacteria are hydrophobic and thus should be able to be separated by froths. A method for producing froth without using chemicals has been developed to avoid water quality deterioration and this froth is shown to hold bacteria without the need for biocide treatment or frothing chemicals. Experiments were undertaken to explore how far this process can purify a water stream. The froths formed were found to hold up to 2×108 cfu ml-1 of bacteria without chemical collectors, and made a cfu/ml drop of 55% between the inlet and outlet streams. The second area of research investigated shock chlorination and dechlorination to kill the microorganisms but almost immediately remove the biocide. Among all the dechlorination techniques, aeration was found to be the most suitable method. Investigations were undertaken to determine how fast and how practically acceptable the method of dechlorination by aeration is. Dechlorination design demand was found to be (9×10-4 lair/(lwater . ppm )). Around these two main areas of research supporting researches were undertaken. Studies found that dead bacteria were able to be removed by froth flotation as well as, or even better than live bacteria. Chlorination was faster than dechlorination under the same conditions by a factor of 25%. At low bacterial content, chlorine demand is directly proportional to cfu/ml. Zero bacterial content can be obtained through shock chlorination. The newly developed iPhone and iPad colony counting applications were investigated as a rapid way of measuring bacterial count. These were found to be reliable and accurate and, with additional manual manipulation proved very suitable to use for counting bacteria.
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50

Shah, Amisha D. "Antibiotics in water treatment the role of water quality conditions on their fate and removal during chlorination and nanofiltration /." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26658.

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Thesis (Ph.D)--Civil and Environmental Engineering, Georgia Institute of Technology, 2009.
Committee Co-Chair: Huang, Ching-Hua; Committee Co-Chair: Kim, Jae-Hong; Committee Member: Li, Qilin; Committee Member: Mulholland, James; Committee Member: Wine, Paul; Committee Member: Yiacoumi, Sotira. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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