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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Možnosti inovace procesu úpravy vody / Water Treatment Plants Innovation Opportunities

Zelený, Zdeněk January 2014 (has links)
This master´s thesis deals with the possibilities of innovation process water treatment. Specifically, to explore the use of sodium water glass and nanoiron in removing heavy metals from raw water at the drinking water treatment. For the comparison was used traditionally used coagulant, particularly liquid aluminum sulfate. The introductory part deals with the possibility of modifying the surface water during the treatment process such water into potable water. This chapter is a description of the quality of raw water used, then the description of currently used separation processes. Furthermore, they are described and commonly used types of treatment plants. Conclusion The introductory section deals with traditional coagulants and form a suspension. Another part of this master´s thesis has been devoted to the possibilities of innovation in the treatment of raw waters as drinking water, describes the options and features of the use of water glass and nanoiron. The following section describes the experimental part of this thesis. It is followed by the experimental results. The last chapter summarizes the acquired knowledge and commented on the measured values of the experimental part. This work also shows several specific projects using innovative technologies presented.
12

Tratamiento de efluentes de la industria alimentaria por coagulación-floculación utilizando almidón de Solanum tuberosum L. ‘papa’ como alternativa al manejo convencional

Molano Linares, Jazmin Desider January 2016 (has links)
Se evaluó el tratamiento de efluentes de la industria alimentaria por coagulación-floculación utilizando almidón de Solanum tuberosum L. „papa‟ como alternativa al manejo convencional. Los ensayos se realizaron a escala de laboratorio realizando la prueba de jarras con dos coagulantes: sulfato de aluminio y policloruro de aluminio, y dos floculantes: poliacrilamida aniónica y almidón gelatinizado, con variaciones en relación a dosis, concentración y velocidad. Para determinar los parámetros ideales se utilizaron las siguientes variables respuesta: índice de Willcomb, absorbancia, turbidez y demanda química de oxígeno. El mejor tratamiento fue con el coagulante policloruro de aluminio y el floculante poliacrilamida aniónica alcanzándose un porcentaje de reducción de DQO de 83,05%. Aun así, los resultados al utilizar almidón sugieren que se puede reemplazar la poliacrilamida aniónica por el almidón de S. tuberosum al aplicar un tratamiento primario a un efluente industrial no doméstico de una empresa alimentaria ubicada en el distrito de Ate en la ciudad de Lima, Perú para cumplir los Valores máximos admisibles del Decreto Supremo N°021-009-Vivienda, en el aspecto de la carga orgánica presente.Treatment of industrial wastewater was evaluated through coagulation-floculation using starch of Solanum tuberosum L. „potato‟ as an alternative to the conventional management. Assays were performed in a laboratory scale by performing Jar Test with two coagulants: aluminum sulfate and aluminum polychloride, and two flocculants: anionic polyacrylamide and gelatinized starch, making variations in dose, concentration and speed. To determine the ideal parameters, the following response variables were used: Willcomb index, absorbance, turbidity and chemical oxygen demand. The best treatment was when using aluminum polychloride as coagulant and anionic polyacrylamide as flocculant, reaching a reduction percentage of 83,05% in chemical oxygen demand. Even then, the results suggest that can the anionic polyacrylamide can be replaced by starch of S. tuberosum when applying a primary treatment to industrial wastewater from a food company located in the district of Ate in Lima, Perú to meet the admisible values set in the Supreme Decree No. 021-009-VIVIENDA, in the aspect of organic matter present in it.
13

Upravitelnost povrchových vod / Treatibility of surface water

Fuks, Josef January 2013 (has links)
The aim of the master´s thesis is the topic of the treatability of surface water with the focus on the process of suspension formation. For this work I took water samples from five different places around the Brno Dam which has contended with water quality deterioration for a long period. With these water samples, the series of jar coagulation tests were done with the application of three different commonly used coagulants. In the theoretical part of the master´s thesis I deal with the composition and attributes of surface water and the technology of its treatment. Each process of treatment is briefly described here with the emphasis on the process of suspension formation. The experimental part of the master´s thesis summarizes and presents the results gained through the coagulation tests in the laboratory. I evaluate the influence of different parameters on final effectiveness of water treatment and I try to find an optimal amount of coagulant, pH and speed of fast or slow mixing. Finally I compare the suitability of each coagulant and the influence of the sampling site on the effectiveness of water treatment.
14

Procesy odželezňování a odmanganování při úpravě podzemní vody / Removal of iron and manganese in water treatment process

Šafaříková, Jana January 2010 (has links)
This diploma thesis is aimed at the evaluation of water treatment technology in Písty waterworks which treats raw water with high concentration of iron and manganese. The most common method of iron and manganese removal from raw water is based on oxidation to insoluble hydrated oxides followed by separation of formed aggregates. The plant technology consists of aeration, oxidation agent KMnO4 dosing and mixing, sedimentation, filtration and hygienic protection. Chemical analysis of treated water, evaluation of the aeration efficiency of iron and manganese oxidation, evaluation of the separation efficiency of the sedimentation tank and filters, assessment of distribution of iron and manganese in the filter, assessment of dirt holding capacity and optimization of KMnO4 dose were determined. Raw water pH fluctuated around 7,3 during measurements, whereas iron and manganese concentrations in raw water were 6,00 and 0,82 mg.l-1 , respectively. Oxidation of 97,2 % of dissolved iron and of 14,3 % of dissolved manganese was achieved after the aeration. The separation efficiency of the sedimentation tank was 82,9 % for iron and 46,5 % for manganese, however the separation efficiency of the second half of the sedimentation tank was low. Thus, the perforated baffles in the second half of the sedimentation...
15

Optimizing Conditions of Coagulation for Removal of Natural Organic Matter (NOM) : Comparison of Removal Efficiency of NOM When Using Bench-Scale Inline Coagulation Over Ultrafiltration and Classical Jar Tests / Optimering av koaguleringsförhållanden för avskiljning av naturligt organiskt material (NOM) : Jämförelse av avskiljningseffektivitet för NOM vid användning av inline-koagulering tillsammans med ultrafiltrering i bänkskala samt klassisk testning

Oveisy, Hiwa January 2023 (has links)
Abstract The removal of Natural Organic Matter (NOM) from water supplies is crucial for the provision of clean, safe drinking water. Lab-scale experiments have been extensively utilized in water treatment facilities to optimize this process. The most used lab-scale method is known as jar test. However, with emerging membrane filtration, lab-scale inline coagulation has been recently utilized to mimic the inline coagulation over membrane filtration in water treatment plants (WTPs).     This study aims to compare the jar test with inline coagulation micro pilot methods from different aspects, including the NOM removal, time, and cost needed for each process. Three case studies were conducted using different water sources in Sweden: Katrineholm, Mälaren, and Mjörn.     In the experiments conducted to find the optimal NOM removal condition, the inline coagulation micro pilot method outperforms the jar test in terms of removal efficiency. In the Katrineholm case, the micro pilot method with a coagulant dosage of 4.5mg/l Al at pH 6.7 achieved removal efficiencies of 63% for fluorescent dissolved organic matter (fDOM), whereas the jar test showed 60% for fDOM but with a significantly higher coagulant dosage (7mg/l) . In the Mälaren case, the micro pilot method using a dosage of 2.5mg/l Al at pH 6.4 yielded removal efficiencies of 62% for UV254, absorbing organic matter and the jar test showed almost the same removal (64%) for UV254 but with a significantly higher coagulant dosage. Finally, in the Mjörn case, the micro pilot method with a coagulant dosage of 3.5mg/l Al at a pH of 6.6 resulted in removal efficiencies of 76% for UV254, the jar test also resulted in 76% for UV254 at the same pH level.     While the micro pilot method showed better removal efficiencies, it consumed more chemicals compared to the jar test. The micro pilot experiments required higher volumes of coagulant and additional chemical backwashing after each set of experiments. In contrast, the jar test method used lesser quantities of coagulant and chemicals due to the smaller scale of the experiments.     The findings of this study highlight the superiority of the inline coagulation micro pilot method over the jar test for optimizing NOM removal in water treatment processes. Despite the jar test being quicker and more cost-effective, it often required higher coagulant dosages to achieve comparable results. This was mainly because jar test demands heavy and large enough flocs to be removed from the water. Conversely, the micro pilot method, although more time-consuming and costly, provided more precise coagulant dosage control, resulted in higher removal efficiencies, and offered a more comprehensive understanding of the coagulation process. This is achieved by using a sensor called EXO sensor, which allows for immediate monitoring of the treatment results.
16

Avaliação de diversos métodos de detecção de cistos de Giardia spp. e Oocistos de Cryptosporidium parvum presentes no resíduo gerado após o tratamento de água de abastecimento com turbidez elevada / Evaluation of several methods for the detection of Giardia spp. cysts and Cryptosporidium parvum Oocysts in wastes produced after high- turbidity water treatment

Giglio, Guilherme Lelis 24 August 2015 (has links)
Este trabalho teve como objetivo avaliar diversos métodos de detecção e recuperação de cistos de Giardia spp. e de oocistos de Cryptosporidium parvum em resíduos gerados no tratamento de águas de abastecimento com turbidez elevada tendo como padrão o Método 1623.1 da USEPA (2012 ). Para tanto, ensaios utilizando aparelho Jarteste (coagulação, floculação, decantação e filtração ) foram realizados utilizando o coagulante cloreto de polialumínio - PAC. Em todos os métodos avaliados foi utilizada a técnica de purificação por separação imunomagnética - IMS. A adaptação do método floculação em carbonato de cálcio FCCa elaborado por Vesey et al. (1993) e adaptado por Feng et al. (2011), repercutiu nos melhores resultados para a amostra de resíduo sedimentado, com recuperações de 68 ± 17 % para oocisto de C. parvum e de 42 ± 7 % para cisto de Giardia spp. Entretanto, as recuperações para a amostra de água de lavagem dos filtros - ALF foram inferiores à 1 %, não sendo possível determinar um método adequado. A presença dos patógenos indica que o reuso da ALF em ETA convencionais ou o descarte em mananciais sem um tratamento prévio, pode representar problemas de contaminação. A adaptação dos métodos de Boni de Oliveira (2012) e Keegan et al. (2008), também repercutiram em porcentagens de recuperação expressivas para a amostra de resíduo sedimentado, sendo de: 41 ± 35 % para oocisto de C. parvum e 11 ± 70 % para cisto de Giardia spp., e 38 ± 26 % para oocisto de C. parvum e 26 ± 13 % para cisto de Giardia spp., respectivamente. A análise estatística não resultou em diferença significativa entre estes dois métodos, entretanto, as elevadas recuperações indicam que estes métodos podem ser melhor avaliados em pesquisas futuras. / This dissertation addresses the evaluation of several methods for the detection of Giardia spp. cysts and Cryptosporidium parvum oocysts in wastes produced after a high-turbidity water treatment, according to Method 1623.1 from USEPA (2012). Coagulant polyaluminium chloride - PACl was used in jar test experiments (coagulation/flocculation, sedimentation and filtration ). The Immunomagnetic Separation - IMS technique was applied to all methods. The calcium carbonate flocculation (CCF) method, developed by Vesey et al. (1993) and adapted by Feng et al. (2011 ), was applied to sludge samples in this research and was the best method tested, with 68% ± 17 % and 42 % ± 7,00 % recoveries for C. parvum oocysts and Giardia spp. cysts, respectively. On the other hand, the percentage recovery of (oo)cysts for filter backwash water samples was lower than 1 % and no suitable method could be detected. The presence of pathogens represents contamination risks for water sources and the reuse of filter backwash water may be a problem to conventional water treatment plants. The application of Boni de Oliveira (2012) and Keegan et al. (2008) methods, adjusted to this study, also resulted in significant percentage recoveries for the sludge samples, with 41 ± 35 % for C. parvum oocyst and 11 ± 70% for cyst Giardia spp., and 38 ± 26% for oocyst C. parvum and 26 ± 13% for cyst Giardia spp., respectively. The statistical analysis showed no significant differences between the two methods, however, such high recoveries indicate they should be better evaluated in future research.
17

Avaliação de diversos métodos de detecção de cistos de Giardia spp. e Oocistos de Cryptosporidium parvum presentes no resíduo gerado após o tratamento de água de abastecimento com turbidez elevada / Evaluation of several methods for the detection of Giardia spp. cysts and Cryptosporidium parvum Oocysts in wastes produced after high- turbidity water treatment

Guilherme Lelis Giglio 24 August 2015 (has links)
Este trabalho teve como objetivo avaliar diversos métodos de detecção e recuperação de cistos de Giardia spp. e de oocistos de Cryptosporidium parvum em resíduos gerados no tratamento de águas de abastecimento com turbidez elevada tendo como padrão o Método 1623.1 da USEPA (2012 ). Para tanto, ensaios utilizando aparelho Jarteste (coagulação, floculação, decantação e filtração ) foram realizados utilizando o coagulante cloreto de polialumínio - PAC. Em todos os métodos avaliados foi utilizada a técnica de purificação por separação imunomagnética - IMS. A adaptação do método floculação em carbonato de cálcio FCCa elaborado por Vesey et al. (1993) e adaptado por Feng et al. (2011), repercutiu nos melhores resultados para a amostra de resíduo sedimentado, com recuperações de 68 ± 17 % para oocisto de C. parvum e de 42 ± 7 % para cisto de Giardia spp. Entretanto, as recuperações para a amostra de água de lavagem dos filtros - ALF foram inferiores à 1 %, não sendo possível determinar um método adequado. A presença dos patógenos indica que o reuso da ALF em ETA convencionais ou o descarte em mananciais sem um tratamento prévio, pode representar problemas de contaminação. A adaptação dos métodos de Boni de Oliveira (2012) e Keegan et al. (2008), também repercutiram em porcentagens de recuperação expressivas para a amostra de resíduo sedimentado, sendo de: 41 ± 35 % para oocisto de C. parvum e 11 ± 70 % para cisto de Giardia spp., e 38 ± 26 % para oocisto de C. parvum e 26 ± 13 % para cisto de Giardia spp., respectivamente. A análise estatística não resultou em diferença significativa entre estes dois métodos, entretanto, as elevadas recuperações indicam que estes métodos podem ser melhor avaliados em pesquisas futuras. / This dissertation addresses the evaluation of several methods for the detection of Giardia spp. cysts and Cryptosporidium parvum oocysts in wastes produced after a high-turbidity water treatment, according to Method 1623.1 from USEPA (2012). Coagulant polyaluminium chloride - PACl was used in jar test experiments (coagulation/flocculation, sedimentation and filtration ). The Immunomagnetic Separation - IMS technique was applied to all methods. The calcium carbonate flocculation (CCF) method, developed by Vesey et al. (1993) and adapted by Feng et al. (2011 ), was applied to sludge samples in this research and was the best method tested, with 68% ± 17 % and 42 % ± 7,00 % recoveries for C. parvum oocysts and Giardia spp. cysts, respectively. On the other hand, the percentage recovery of (oo)cysts for filter backwash water samples was lower than 1 % and no suitable method could be detected. The presence of pathogens represents contamination risks for water sources and the reuse of filter backwash water may be a problem to conventional water treatment plants. The application of Boni de Oliveira (2012) and Keegan et al. (2008) methods, adjusted to this study, also resulted in significant percentage recoveries for the sludge samples, with 41 ± 35 % for C. parvum oocyst and 11 ± 70% for cyst Giardia spp., and 38 ± 26% for oocyst C. parvum and 26 ± 13% for cyst Giardia spp., respectively. The statistical analysis showed no significant differences between the two methods, however, such high recoveries indicate they should be better evaluated in future research.
18

Vznik mikrosuspenze perikinetickou a ortokinetickou koagulací / Formation of microsuspension by perikinetic and orthokinetic koagulation

Fojtíková, Radka January 2008 (has links)
This diploma thesis is focused on study of physico-chemical influences on model surface-water treatment which contain humic compounds. From those factors were monitored especially the dose of destabilizing reagent, pH value, temperature, velocity gradient of mixing and time of its duration. As destabilizing reagents were used Al2(SO4)3 .18H2O a Fe2(SO4)3 . 9H2O.
19

The Effect of Selected Coagulants on Chloride-to-Sulfate Mass Ratio for Lead Control and on Organics Removal in Two Source Waters

El Henawy, Walid January 2009 (has links)
Lead is a known toxin, with the ability to accumulate in the human body from as early as fetal development. Lead exposure is known to cause a myriad of health effects which are more prominent among children. Health effects upon exposure can range from renal and heart disease or potentially cancer in adults to neurotoxicity in children. The continued presence of old lead service lines and plumbing in distribution systems as well as lead-containing solders and brass fixtures in homes may contribute lead to drinking water. Recent studies have highlighted the importance of a predictor known as the chloride-to-sulfate mass ratio (CSMR) in controlling lead release. A ratio above 0.5 – 0.6 theoretically increases the aggressiveness of lead leaching in galvanic settings, while a lower ratio controls lead corrosion. A switch in coagulant type could significantly alter the ratio. However, a coagulant switch could also trigger changes in finished water turbidity and organics, including disinfection by-product (DBP) precursors, as well as impact sludge production. Anecdotal evidence from an Ontario water treatment utility suggested the potential applicability of a newly formulated polymer, cationic activated silica (CAS), in improving DBP precursor removal when used in concurrence with a primary coagulant. No previous scientific research had been dedicated to testing of the polymer. The present research had three primary objectives: The first was to investigate the effect of conventional coagulation with six different coagulants on the chloride-to-sulfate mass ratio as it pertains to lead corrosion in two Ontario source waters of differing quality. Additionally, the effect of coagulant choice on pH, turbidity, and organics removal was investigated. The second objective was aimed at testing potential reductions in CSMR and organics that could be brought about by the use of two polymers, cationic and anionic activated silica (CAS and AAS, respectively), as flocculant aids. Finally, the performance of a high-rate sand-ballasted clarification process was simulated at bench-scale to gauge its performance in comparison with conventional coagulation simulation techniques. The first series of jar-tests investigated the effectiveness of CAS as a primary coagulant on Lake Ontario water. In comparison with the conventional coagulants aluminum sulfate and polyaluminum chloride, CAS did not offer any apparent advantage with respect to turbidity and organics removal. Testing of CAS and AAS as flocculant aids was also conducted. Results from a full factorial experiment focused on CAS testing on Lake Ontario water showed that coagulant dose is the most significant contributor to CSMR, turbidity, DOC removal, and THM control. Generally, improvements resulting from CAS addition were of small magnitude (<15%). Reductions in CSMR were attributed to the presence of the sulfate-containing chemicals alum and sulfuric acid in the CAS formulation. Testing of sulfuric acid-activated AAS on Grand River water showed that pairing of AAS with polyaluminum chloride provides better results than with alum with respect to DOC removal (39% and 27% respectively at 60 mg/L coagulant dose). Highest turbidity removals (>90%) with both coagulants were achieved at the tested coagulant and AAS doses of 10 mg/L and 4 mg/L respectively. CSMR reductions in the presence of AAS were also attributable to sulfate contribution from sulfuric acid. Bench-scale simulation of a high-rate sand-ballasted clarification process on Grand River water showed comparable removal efficiencies for turbidity (80 – 90% at 10 mg/L), and DOC (30 – 40% at 50 mg/L). Finally, six different coagulants were tested on the two source waters for potential applicability in CSMR adjustment in the context of lead corrosion. The two chloride-containing coagulants polyaluminum chloride and aluminum chlorohydrate increased CSMR in proportion to the coagulant dose added, as would be expected. Average chloride contribution per 10 mg/L coagulant dose was 2.7 mg/L and 2.0 mg/L for polyaluminum chloride and aluminum chlorohydrate, respectively. Sulfate-contributing coagulants aluminum sulfate, ferric sulfate, pre-hydroxylated aluminum sulfate, and polyaluminum silicate sulfate reduced CSMR as coagulant dose increased, also as would be expected. The highest sulfate contributors per 10 mg/L dose were pre-hydroxylated aluminum sulfate (6.2 mg/L) and ferric sulfate (6.0 mg/L). The lowest CSMR achieved was 0.6 in Lake Ontario water at a 30 mg/L dose and 0.8 in Grand River water at a 60 mg/L dose. Highest DOC removals were achieved with the chloride-containing coagulants in both waters (35 – 50%) with aluminum chlorohydrate showing superiority in that respect. DOC removals with sulfate-containing coagulants were less, generally in the range of 22 – 41%. Specificity of critical CSMR values to source water needs to be investigated. Additionally, long term effects of sustained high or low CSMR values in distribution systems need to be further looked into. Finally, the effect of interventions to alter CSMR on other water quality parameters influencing lead corrosion such as pH and alkalinity still represent a research deficit.
20

The Effect of Selected Coagulants on Chloride-to-Sulfate Mass Ratio for Lead Control and on Organics Removal in Two Source Waters

El Henawy, Walid January 2009 (has links)
Lead is a known toxin, with the ability to accumulate in the human body from as early as fetal development. Lead exposure is known to cause a myriad of health effects which are more prominent among children. Health effects upon exposure can range from renal and heart disease or potentially cancer in adults to neurotoxicity in children. The continued presence of old lead service lines and plumbing in distribution systems as well as lead-containing solders and brass fixtures in homes may contribute lead to drinking water. Recent studies have highlighted the importance of a predictor known as the chloride-to-sulfate mass ratio (CSMR) in controlling lead release. A ratio above 0.5 – 0.6 theoretically increases the aggressiveness of lead leaching in galvanic settings, while a lower ratio controls lead corrosion. A switch in coagulant type could significantly alter the ratio. However, a coagulant switch could also trigger changes in finished water turbidity and organics, including disinfection by-product (DBP) precursors, as well as impact sludge production. Anecdotal evidence from an Ontario water treatment utility suggested the potential applicability of a newly formulated polymer, cationic activated silica (CAS), in improving DBP precursor removal when used in concurrence with a primary coagulant. No previous scientific research had been dedicated to testing of the polymer. The present research had three primary objectives: The first was to investigate the effect of conventional coagulation with six different coagulants on the chloride-to-sulfate mass ratio as it pertains to lead corrosion in two Ontario source waters of differing quality. Additionally, the effect of coagulant choice on pH, turbidity, and organics removal was investigated. The second objective was aimed at testing potential reductions in CSMR and organics that could be brought about by the use of two polymers, cationic and anionic activated silica (CAS and AAS, respectively), as flocculant aids. Finally, the performance of a high-rate sand-ballasted clarification process was simulated at bench-scale to gauge its performance in comparison with conventional coagulation simulation techniques. The first series of jar-tests investigated the effectiveness of CAS as a primary coagulant on Lake Ontario water. In comparison with the conventional coagulants aluminum sulfate and polyaluminum chloride, CAS did not offer any apparent advantage with respect to turbidity and organics removal. Testing of CAS and AAS as flocculant aids was also conducted. Results from a full factorial experiment focused on CAS testing on Lake Ontario water showed that coagulant dose is the most significant contributor to CSMR, turbidity, DOC removal, and THM control. Generally, improvements resulting from CAS addition were of small magnitude (<15%). Reductions in CSMR were attributed to the presence of the sulfate-containing chemicals alum and sulfuric acid in the CAS formulation. Testing of sulfuric acid-activated AAS on Grand River water showed that pairing of AAS with polyaluminum chloride provides better results than with alum with respect to DOC removal (39% and 27% respectively at 60 mg/L coagulant dose). Highest turbidity removals (>90%) with both coagulants were achieved at the tested coagulant and AAS doses of 10 mg/L and 4 mg/L respectively. CSMR reductions in the presence of AAS were also attributable to sulfate contribution from sulfuric acid. Bench-scale simulation of a high-rate sand-ballasted clarification process on Grand River water showed comparable removal efficiencies for turbidity (80 – 90% at 10 mg/L), and DOC (30 – 40% at 50 mg/L). Finally, six different coagulants were tested on the two source waters for potential applicability in CSMR adjustment in the context of lead corrosion. The two chloride-containing coagulants polyaluminum chloride and aluminum chlorohydrate increased CSMR in proportion to the coagulant dose added, as would be expected. Average chloride contribution per 10 mg/L coagulant dose was 2.7 mg/L and 2.0 mg/L for polyaluminum chloride and aluminum chlorohydrate, respectively. Sulfate-contributing coagulants aluminum sulfate, ferric sulfate, pre-hydroxylated aluminum sulfate, and polyaluminum silicate sulfate reduced CSMR as coagulant dose increased, also as would be expected. The highest sulfate contributors per 10 mg/L dose were pre-hydroxylated aluminum sulfate (6.2 mg/L) and ferric sulfate (6.0 mg/L). The lowest CSMR achieved was 0.6 in Lake Ontario water at a 30 mg/L dose and 0.8 in Grand River water at a 60 mg/L dose. Highest DOC removals were achieved with the chloride-containing coagulants in both waters (35 – 50%) with aluminum chlorohydrate showing superiority in that respect. DOC removals with sulfate-containing coagulants were less, generally in the range of 22 – 41%. Specificity of critical CSMR values to source water needs to be investigated. Additionally, long term effects of sustained high or low CSMR values in distribution systems need to be further looked into. Finally, the effect of interventions to alter CSMR on other water quality parameters influencing lead corrosion such as pH and alkalinity still represent a research deficit.

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