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Seasonal periods of high rainfall have led to difficulties in removing sufficient natural organic matter (NOM) to meet trihalomethane (THM) standards, and hence better or alternative treatments are required. Typically bulk water parameters such as dissolved organic carbon (DOC) and UV absorbance at 254nm (UV254) are used to optimise treatment processes. Here the isolated fraction character and molecular weight (MW) distribution was used in conjunction with bulk water parameters to tailor process options for the treatment of humic rich waters. Three options for the removal of NOM were proposed. A staged coagulation based on the optimisation of isolated fractions. The results showed that although no significant reduction in DOC or UV254 was observed filter breakthrough was significantly reduced. Secondly a novel magnetic ion exchange process (MIEX®) for the removal of NOM was evaluated. The results showed that a combination of MIEX® and ferric reduced the THM formation potential (THMFP) by more than 50% and lower MW compounds that are known to be untreated by conventional coagulation were reduced. This option was also shown to be the most robust option for the treatment of waters with differing quality caused by seasonal changes and different catchments. Finally the addition of a range of adsorbents including carbons, hydroxides and clays to both the raw water and the isolated low MW fractions showed that an increase in DOC and UV254 removal was achievable. This was proposed as a post coagulation option during times of high organic loading. All processes provide viable options for the treatment of humic rich waters during times when current processes are being challenged and having difficulty meeting THM standards.

An exploratory analysis of the trihalomethane (THM) and haloacetic acid (HAA) formation potential (FP) of Cedar Lake in order to produce formation potential curves for both THM and HAA; determine the THMFP and rate constant and compare to previous studies on Cedar Lake; and develop modeling for the formation potential loss of HAA from laboratory analysis of the raw lake water. While extensive modeling approaches have been explored for THM formation on different water sources, not many have been applied to the reservoir that supplies water to the Carbondale Water Treatment Plant and even fewer have explored the formation and modeling of HAA. Data for this study was obtained through laboratory experiment by applying bleach as a substitute for free chlorine to raw water samples obtained from Cedar Lake and quenching the samples at specific time steps to stop the reaction. Samples were then analyzed for THM content using standard method EPA 524.2R4.1 and HAA content using standard method EPA 552.2. The observed peak formation was 641.2701 µg/L for THM and 426.8 µg/L for HAA, but modeling fitted to the laboratory results indicated that a lower FP provided a better fitting of the data. A detailed analysis of the formed THM and HAA compounds indicated that a model produced for each compound resulted in more appropriate fitting by being able to account for the differing reaction rates and limiting factors of each reaction.

Made available in DSpace on 2014-06-11T19:29:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-08-16Bitstream added on 2014-06-13T20:38:39Z : No. of bitstreams: 1 cesco_dd_me_ilha.pdf: 575055 bytes, checksum: 812d7bbf5c5a525f1a7625caabd57c5c (MD5) / A cloração das águas na presença de precursores da formação de SPDs, oriundos da MON forma entre estes os THMs, cujos principais compostos são o clorofórmio, bromodiclorometano, dibromoclorometano e bromofórmio, potencialmente cancerígenos ao ser humano. No ano de 1974, os THMs foram detectados na água potável nos Estados Unidos e estudos da época apresentaram as primeiras indicações da existência de correlação entre água de abastecimento, THMs e câncer e, estudos posteriores, levaram à fixação de valores limites dos mesmos. No Brasil o valor máximo para os THMs está fixado em 100 g/L na água para consumo humano, de acordo com a Portaria nº. 518/04 (BRASIL, 2004), mas estes valores limites são variáveis em outros países. O presente estudo buscou identificar a formação de THMs, gerados a partir da reação do cloro com a MON, avaliando a formação com e sem a pré-oxidação com cloro na ETA da SABESP de Presidente Epitácio SP, em escala real, onde as concentrações da MON foram reduzidas pelas etapas do processo de tratamento (coagulação, floculação, decantação e filtração), com a mudança do coagulante de cloreto férrico para PAC e, avaliou-se a formação de THM na rede de distribuição. A quantificação de THM foi realizada pelas técnicas de cromatografia gasosa e da MON através da leitura da absorbância à radiação ultravioleta visível no comprimento de onda a 254 nm em espectrofotômetro UV254, parâmetro indireto com filtração da amostra. As análises da MON mostraram que o sistema de tratamento de água não removeu todos compostos orgânicos naturais, que na presença do cloro residual disponível na rede, mostrou tendência de aumentar a formação de THM durante o seu percurso. / The chlorination of the water, when the presence of disinfections by-products are formed, resulting from Natural Organic Matter (NOM), forms among them the trihalomethanes (THMs), which is mainly composed by chloroform (CHCl3), bromodichloromethane (CHBrCl2), dibromochloromethane (CHBr2Cl) and bromoform (CHBr3), that are potentially cancerous to humans. In 1974, the THMs were detected in the drinking water in the USA and studies, at the time, showed the first indications of the drinking water correlation, THMs and cancer disease and, further studies brought to fixation of limits for them. In Brazil, the maximum value for the THMs is fixed in 100μg/l in the drinking water, according to government act nº 518/04 (BRASIL, 2004), however those limits varied from country to country. The present research identified the formation of THMs, generated from the reaction of the chlorine with NOM, evaluating the formation with or without the pre-oxidation with chlorine in the SABESP Water Treatment Plant at the Presidente Epitacio city (São Paulo State), in full scale, where the concentrations of the NOM were reduced by the different phases of the treatment process (coagulation, flocculation, decantation and filtration), with the change of the coagulant from iron chloride to Poli Aluminum Chloride (PAC) and, the formation of THM was found at the distribution net. The quantification of THM was made by the gas chromatography technique and NOM are reading in the 254 nm absorbance radiation wave length in an UV spectrophotometer, indirect sample with filtration. The analysis of the NOM showed that the water treatment system did not remove all the natural organic compounds, that in the presence of residual chlorine available in the net, showed increasing tendency to form THM.

Resumo: A cloração das águas na presença de precursores da formação de SPDs, oriundos da MON forma entre estes os THMs, cujos principais compostos são o clorofórmio, bromodiclorometano, dibromoclorometano e bromofórmio, potencialmente cancerígenos ao ser humano. No ano de 1974, os THMs foram detectados na água potável nos Estados Unidos e estudos da época apresentaram as primeiras indicações da existência de correlação entre água de abastecimento, THMs e câncer e, estudos posteriores, levaram à fixação de valores limites dos mesmos. No Brasil o valor máximo para os THMs está fixado em 100 g/L na água para consumo humano, de acordo com a Portaria nº. 518/04 (BRASIL, 2004), mas estes valores limites são variáveis em outros países. O presente estudo buscou identificar a formação de THMs, gerados a partir da reação do cloro com a MON, avaliando a formação com e sem a pré-oxidação com cloro na ETA da SABESP de Presidente Epitácio SP, em escala real, onde as concentrações da MON foram reduzidas pelas etapas do processo de tratamento (coagulação, floculação, decantação e filtração), com a mudança do coagulante de cloreto férrico para PAC e, avaliou-se a formação de THM na rede de distribuição. A quantificação de THM foi realizada pelas técnicas de cromatografia gasosa e da MON através da leitura da absorbância à radiação ultravioleta visível no comprimento de onda a 254 nm em espectrofotômetro UV254, parâmetro indireto com filtração da amostra. As análises da MON mostraram que o sistema de tratamento de água não removeu todos compostos orgânicos naturais, que na presença do cloro residual disponível na rede, mostrou tendência de aumentar a formação de THM durante o seu percurso. / Abstract: The chlorination of the water, when the presence of disinfections by-products are formed, resulting from Natural Organic Matter (NOM), forms among them the trihalomethanes (THMs), which is mainly composed by chloroform (CHCl3), bromodichloromethane (CHBrCl2), dibromochloromethane (CHBr2Cl) and bromoform (CHBr3), that are potentially cancerous to humans. In 1974, the THMs were detected in the drinking water in the USA and studies, at the time, showed the first indications of the drinking water correlation, THMs and cancer disease and, further studies brought to fixation of limits for them. In Brazil, the maximum value for the THMs is fixed in 100μg/l in the drinking water, according to government act nº 518/04 (BRASIL, 2004), however those limits varied from country to country. The present research identified the formation of THMs, generated from the reaction of the chlorine with NOM, evaluating the formation with or without the pre-oxidation with chlorine in the SABESP Water Treatment Plant at the Presidente Epitacio city (São Paulo State), in full scale, where the concentrations of the NOM were reduced by the different phases of the treatment process (coagulation, flocculation, decantation and filtration), with the change of the coagulant from iron chloride to Poli Aluminum Chloride (PAC) and, the formation of THM was found at the distribution net. The quantification of THM was made by the gas chromatography technique and NOM are reading in the 254 nm absorbance radiation wave length in an UV spectrophotometer, indirect sample with filtration. The analysis of the NOM showed that the water treatment system did not remove all the natural organic compounds, that in the presence of residual chlorine available in the net, showed increasing tendency to form THM. / Orientador: Tsunao Matsumoto / Coorientador: Edson Pereira Tangerino / Banca: Milton Dall'Aglio Sobrinho / Banca: Marcelo Libânio / Mestre

Historically, chlorination has been widely utilized as a primary and secondary disinfectant in municipal water supplies. Although chlorine disinfection is effective in inactivating pathogenic microbes, the use of chlorine creates the unintentional formation of regulated chemicals. On January 4, 2006, the United States Environmental Protection Agency (EPA) promulgated the Stage 2 Disinfectants/Disinfection by-product rule (DBPR) that focuses on public health protection by limiting exposure to four trihalomethanes (THM) and five haloacetic acids (HAA5), formed when chlorine is used for microbial pathogen control. This thesis examines post-aeration TTHM formation when employing spray-aeration processes to remove semi-volatile TTHMs from chlorinated potable water supplies. A bench scale air stripping unit was designed, constructed and operated to evaluate spray aeration for the removal of the four regulated trihalomethane (THM) species from potable drinking water including bromodichloromethane, bromoform, dibromochloromethane, chloroform. The study was conducted using finished bulk water samples collected from two different water treatment facilities (WTFs) located in Oviedo and Babson Park, Florida. Both treatment plants treat groundwater; however, Oviedo's Mitchell Hammock WTF (MHWTF) supply wells contain dissolved organic carbon and bromide DBP precursors whereas the Babson Park WTF #2 (BPWTF2) supply well contains dissolved organic carbon DBP precursors but is absent of bromide precursor. Three treatment scenarios were studied to monitor impacts on total trihalomethane (TTHM) removal and post-treatment (post-aeration) TTHM formation potential, including 1) no treatment (non-aerated control samples), 2) spray aeration via specially fabricated GridBee® nozzle for laboratory-scale applications, 3) spray aeration via a commercially available manufactured BETE® nozzle used for full-scale applications. Select water quality parameters, chlorine residual, and total trihalomethane concentrations were monitored throughout the study. The GridBee® spray nozzle resulted in TTHM removals ranging from 45.2 ± 3.3% for the BPWTF2 samples, and 37.7 ± 3.1% for the MHWTF samples. The BETE® spray nozzle removed 54.7±3.9% and 48.1±6.6% of total trihalomethanes for the Babson Park and Mitchell Hammock WTF samples, respectively. The lower percent removals at the MHWTF are attributed to the detectable presence of bromide and subsequent formation of hypobromous acid in the samples. Post spray aeration TTHM formation potentials were monitored and it was found that the MHWTF experienced significantly higher formation potentials, once again due to the presence of hypobromous acid which led to increases in overall TTHM formation over time in comparison with the Babson Park WTF #2 TTHM formation samples. In addition, chlorine residuals were maintained post spray aeration treatment, and initial chlorine residual and trihalomethane concentrations did not significantly impact overall spray nozzle performance. Among other findings, it was concluded that spray nozzle aeration is a feasible option for the Babson Park WTF #2 for TTHM compliance. For Oviedo's Mitchell Hammock WTF spray aeration was successful in removing TTHMs, however it was not effective in maintaining DBP rule compliance due to the excessive nature of DBP formation in the water samples. This study was not intended to serve as an assessment of varying nozzle technologies; rather, the focus was on the application of spray aerators for TTHM removal and post-formation in drinking water systems.

As a result of the EPA?s Disinfection Byproduct Rule, the Northeast Mississippi Regional Water Supply District requested that the Environmental Technology and Applications Laboratory at Mississippi State University conduct a study to develop techniques to comply with new TOC regulations. This study involved the use of jar testing and Enhanced Coagulation in a laboratory setting over a period of twelve months to optimize the various coagulants evaluated in this study. Iron (III) sulfate, aluminum sulfate, aluminum chloride, aluminum chlorohydrate, and a number of polyaluminum chlorides were evaluated in this study. Coagulants were evaluated on both a treatment effectiveness and economical basis. It was determined that an acidified alum solution performed best at meeting EPA standards for total organic carbon reduction, as well as being economically feasible.

Many Canadian water treatment plants supplied by surface waters of the Canadian Prairie and Shield have elevated concentrations of trihalomethanes (THMs), which exceed the provincial standards. These water sources are characterized by elevated levels of dissolved organic carbon (DOC) and varying levels of calcium hardness, which causes a challenge for the removal of THMs precursors. The objective of this study was to investigate the effect of two treatment methods: chemical coagulation and pre-ozonation-coagulation on the removal of DOC as the main THMs precursor. Surface waters typical for the Canadian Prairie and Canadian Shield were used in the experiments which includes Assiniboine River, Red River, and Rainy River. The effects of different experimental conditions such as coagulant dose, coagulant type, and solution pH as well as ozone dosage on THMs removal were investigated. The structural and chemical characteristics of natural organic matter and isolated humic substances, before and after the reaction with ozone, were studied using spectroscopic techniques. The results illustrated that the quality of source water (DOC characteristics, concentration of water DOC and Calcium) has a significant impact on THMs reduction by chemical coagulation and ozonation. Coagulation results showed that reduction of total DOC does not guarantee THMFP reduction and chemical coagulation should be optimized to remove the hydrophobic acid fraction which forms most THMs. The removal of DOC by aluminum-based coagulants was affected more by the concentration of polymeric and colloidal aluminum speciation. This finding is especially important for plants supplied by high alkalinity waters where pH adjustment is a serious challenge. The effect of pre-ozonation on coagulation varies depending on the concentration of calcium, which has the ability to form complexes with DOC compounds promoting their removal in coagulation. For the surface water with high levels of organic carbon and calcium hardness, ozonation prior to coagulation was beneficial in terms of DOC reduction. However, it showed the opposite effect on water with high levels of DOC accompanied with low level of calcium hardness. Spectroscopic results showed that ozonation of NOM and humic substances cause a significant reduction of aromatic and highly conjugated compounds (constituting primarily the hydrophobic acid fraction). / February 2016

Orientador: Jose Euclides Stipp Paterniani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-09T17:15:08Z (GMT). No. of bitstreams: 1 Silva_MarceloJacominiMoreirada_D.pdf: 4911036 bytes, checksum: 621ab01f5e1f061dd69cb5599e64882b (MD5) Previous issue date: 2006 / Resumo: presente trabalho estudou a melhoria da qualidade de esgoto sanitário tratado com a utilização de pré-filtração em pedregulho, filtração lenta com e sem carvão ativado, cloração, radiação ultravioleta (UV) e radiação solar em fluxo contínuo (SODIS). A unidade piloto constituía um pré-filtro de pedregulho em camadas com fluxo ascendente cujo efluente é destinado a dois filtros lentos com meio filtrante composto de areia com 40cm de espessura (num dos filtros foi inserida, uma camada de 10cm de espessura de carvão vegetal ativado granulado) e 3 camadas de mantas sintéticas não tecidas instaladas no topo da camada de areia seguindo de desinfecção foi realizada em três sistemas paralelos: cloração com hipoclorito de sódio; radiação UV com reator do tipo tubular e lâmpada bactericida submersa; radiação SODIS em fluxo contínuo. O pré-filtro de pedregulho apresentou eficiência de remoção de sólidos em suspensão, atenuou ainda, os picos de concentração de sólidos em suspensão e turbidez no efluente, garantido ao afluente dos filtros lentos menor variabilidade das suas características qualitativas. Os filtros lentos, com e sem carvão granulado, tiveram comportamentos semelhantes com relação a evolução da perda de carga e os resultados mostraram que a utilização do carvão ativado proporciona melhor remoção das impurezas, avaliadas pelos parâmetros adotados. A desinfecção com radiação UV atingiu eficiência próxima a cloração sendo um processo alternativo com menor risco de formação de produtos carcinogênicos, como os trialometanos. A radiação solar (SODIS) não atingiu valores adequados, uma vez que a temperatura no efluente não chegou à 50ºC, e apresentou problemas relativos à proliferação de algas. Concluiu-se que a utilização de tais tecnologias, além de serem de custo baixo e de simples operação e manutenção, conferem ao efluente melhores características físicas e biológicas, de tal modo que se pode adequar o efluente para o reúso em atividades de irrigação e o lançamento em corpos d'água / Abstract: The current work demonstrates the viability of domestic wastewater quality improvement by the slow filtration preceded roughing filtration and disinfection by ultraviolet and solar radiation. The pilot plant is constituided of two slow sand filters with 40 cm sand layer thickness and 3 layers of synthetic non woven fabrics installed in the top of the sand layer. Besides, in one of the filters there was inserted 10 cm thickness of granulated vegetal coal. The roughing filter presented efficiency of 22.5% in suspended solids removal, and 22.8% in turbidity removal. The slow filter with granulated coal s, had similar behaviors with the slow sand filter with only sand, regard to evolution of the head loss, so the initial average value was 6.2cm and 7.1cm, respectively. The average of the filtration run was of 40days. The results showed that the use of granulated coal better provides removal of the water impurities. The disinfections systems are installed after the filters. The efficiencies of removal in the slow filter with sand and blanket and of the slow filter I only contend sand coal and weaveeed blanket had not been, respectively: 28% and 36% for solids in suspension, 33% and 43% for turbidez, 26% and 39% for apparent color, 57% and 74% for total coliformes and 70% and 73% for E.coli. The chlorination has done with pump whose applies 2mg_-1 NaOHCl. The UV reactor has tubular layout. The SODIS reactor has continuous flow, TDH = 4hours. The use of such technologies was concluded that, beyond being of cost low e of simple operation and maintenance, confers to effluent the better physical and biological characteristics, being possible still to increase this efficiency with the use of granulated coal. The use of any insumo chemical is still standed out not during the treatment of the effluent one, becoming the applicable process in communities whose infrastructure is precarious. The evaluated system if still gives to adjust the water for reúso in activities that do not demand potable quality / Doutorado / Saneamento e Ambiente / Doutor em Engenharia Civil

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