Secondary effluent from the Roger Road Wastewater Treatment Plant undergoes tertiary treatment of dual media filtration and chlorination. The tertiary effluent is recharged and subsequently extracted for irrigation in Tucson, Arizona. The fate of chlorinated organics in this recharge system was investigated in this research. Nonpurgeable organic carbon was found to reach a constant level in the groundwater after being recharged. Not all of the organic carbon was removed from the water. Nonpurgeable organic halogens increased as they flowed away from the recharge basins. Reasons for this increase were not determined. Attempts were made to define the apparent molecular weight distribution of the NPOC and the NPOX. Measured values of the two parameters were consistently greater after the analytical processing than before, making the determination impossible.

A study has been conducted for the qualitative and Quantitative analysis of chlorinated organic compounds in water. The study included the adaptation of Amberlite XAD macroreticular resin techniques for the concentration of municipal wastewater samples, followed by GC/MS analysis. A new analytical method was developed for the determination of volatile halogenated organics using liquid-liquid extraction and electron capture gas chromatography. And, a computer program was written which searches raw GC/MS computer files for halogen-containing organic compounds.

The removal of microbial populations from potable water has been a practice with great importance towards public health, as it has resulted in the reduction of literally millions of cases of infectious disease. In the United States, pathogenic organisms are most commonly removed from drinking water through the application of chlorine. Ninety-nine per cent of all U.S. potable water treatment facilities that disinfect, rely on chlorine as their sole or primary disinfectant, and over 175,000,000 Americans regularly consume chlorinated water. In 1974, Rook and Bellar et al. published studies which indicated that chlorine reacted with organic matter in water during treatment to produce a wide-range of halogenated by-products. Since that time, numerous analyses have been performed to isolate and identify the by-products of chlorination. Toxicologic and epidemiologic studies have been performed, some of which suggest that the use of chlorine as a disinfectant may be contributing to the incidence of chronic disease in the United States. Because of the concern that the use of chlorine for potable water disinfection may be contributing to chronic disease, Amendments to the Safe Drinking Water Act (SDWA) have been promulgated which strictly regulate disinfectants and disinfection by-products. Future disinfectant and disinfectant by-product regulations (1992) will have a major impact on the purveyors of potable water in the U.S.. Probably the largest challenge U.S. water treatment utilities now face is in the attempt to control for disinfectants and disinfectant by-products while maintaining the microbiological integrity of the water supply. The SDWA Amendments and their supporting regulations will result in major changes in the way water quality parameters are measured, and the way disinfection and treatment strategies are practiced. This thesis looks closely at the role of chlorine as a disinfectant, the by-products arising from chlorine reacting with organic matter, as well as the rationale behind the disinfectant and disinfectant by-product regulations. After examining the chemical, toxicologic and epidemiologic evidence which fueled the new SDWA regulations, available treatment strategies for meeting the new regulations will be detailed and examined. A water treatment strategy which best appears to maximize the reduction of waterborne disease and minimize the risk of chronic disease will then be offered. / Graduation date: 1992

Orientador: Ruben Bresaola Júnior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-17T01:59:19Z (GMT). No. of bitstreams: 1 Franquini_PauloEduardo_M.pdf: 2223374 bytes, checksum: daba13dae2b6107bdc84e30e66001bf8 (MD5) Previous issue date: 2010 / Resumo: A presente pesquisa teve por objetivo avaliar, em escala de laboratório, a formação de subprodutos da desinfecção (SPD), aldeídos (ALD) e trialometanos (THM), originados a partir da oxidação em soluções contendo ácidos húmicos na presença ou não de íons brometo, sob a ação do cloro livre, sob diferentes concentrações e tempos de contato. A técnica analítica utilizada foi a extração líquido-líquido e cromatografia gasosa com detector de captura de elétrons, a qual proporcionou a separação dos SPD originados em espécies: formaldeído, acetaldeído, glioxal, metilglioxal, clorofórmio, bromodiclorometano, dibromoclorometano e bromofórmio. A presença de íons brometo proporcionou maiores concentrações de ALD totais (TALD) e THM totais (TTHM), sob o tempo de contato de 12 h e 24 h, respectivamente. A variação de concentração de íons brometo de 0,50 para 2,00 mg L?1, promoveu uma depreciação na concentração de TALD em 12 h e uma inversão nas concentrações das espécies predominantes que existiam na ausência dos íons. A inversão nas concentrações das espécies predominantes de THM que existiam na ausência dos íons também foi presenciada, sendo que prevaleceram as espécies bromadas em detrimento das cloradas. Os resultados com íons brometo indicaram a possibilidade da existência de reações de oxidação competitivas para cada grupo de SPD e discutidas no trabalho. A remoção dos SPD foi realizada por adsorção mediante a utilização de carvão ativado em pó (CAP) em diferentes dosagens e com tempos de detenção do CAP de 60 e 120 min, seguido de simulação, em laboratório, do tratamento convencional de água, utilizando-se o sulfato de alumínio como coagulante. Os resultados destes ensaios realizados demonstraram remoções da ordem de 77% para os aldeídos totais, empregando-se dosagem de 30 mg L?1 de CAP e de 86% para os THM totais, empregando-se dosagem de 100 mg L?1 do mesmo, ambas as remoções sob tempo de detenção de 60 min. Os resultados de remoções de THM totais proporcionaram a adequação da água nos limites estabelecidos pela legislação brasileira e permitiram realizar simulações de custo do CAP a ser utilizado nas estações de tratamento de água / Abstract: The present research was to evaluate, in laboratory scale, the formation of disinfection byproducts (DPB), aldehydes (ALD) and trihalomethanes (THM), originated from the oxidation in solutions containing humic acids in the presence or not of ions bromide, under the action of free chlorine, under different concentrations and timing contact. The analytical technique used was the extraction liquid-liquid and gás chromatography with electrons detector capture, which provided the separation of DPB originated in species: formaldehyde, acetaldehyde, glyoxal, methyl-glyoxal, chloroform, bromodichloromethane, dibromochloromethane and bromoform. The presence of íons bromide gave higher concentrations of total ALD (TALD) and total THM (TTHM), under the time contact of 12 h and 24 h, respectively. The variation in the concentration of íons bromide from 0,50 to 2,00 mg L?1, caused depreciation in the concentration of TALD and a reversal in concentrations of predominant species that existed in the absence of ions. The reversal in concentrations of the THM predominant species that existed in the íons absence was also seen, and the brominated species prevailed at the detriment of chlorinated ones. The results with ions bromide indicated the possibility of the existence of competitive oxidation reactions for each group of DPB and it was discussed on the work. The removal of DPB was performed by adsorption using powdered activated carbon (PAC) in different dosages and with times of detention of PAC of 60 and 120 min, followed by simulation of the conventional water treatment, in the laboratory, using aluminum sulphate as coagulant. The adsorption test results, followed by coagulation, flocculation, sedimentation and filtration, showed removals of the order of 77% for TALD, using dosage of 30 mg L?1 PAC, and 86% for TTHM, using dosage of 100 mg L?1 of the same, both removals under detention time of 60 min. The total THM removal results gave the adequacy of water within the limits established by Brazilian legislation and allowed the realizations of simulations of cost of PAC to be used in water treatment / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil

Orientador: Ruben Bresaola Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-05T11:49:09Z (GMT). No. of bitstreams: 1 Marmo_CarlosRenato_M.pdf: 2657579 bytes, checksum: 5995fb2c9ebb8d2a626b9bc6f6ec4b0f (MD5) Previous issue date: 2005 / Resumo: A presente pesquisa avaliou, em escala de laboratório, a formação de trihalometanos (THM) produzidos em reações de oxidação, com cloro livre, de amostras de água contendo ácidos húmicos, sob diferentes concentrações e tempos de contato. O estudo também abrangeu a presença do íon brometo, como forma de se avaliar, qualitativa e quantitativamente, as diferentes espécies de THM produzidas. A detecção dos trihalometanos formados foi realizada, comparativamente, através de duas técnicas analíticas. A cromatografia gasosa, indicada para a análise de tais moléculas, permitiu a quantificação dos compostos clorofórmio, diclorobromometano, dibromoclorometano e bromofórmio. A espectrofotometria foi avaliada como metodologia alternativa à primeira, permitindo a expressão dos resultados apenas em THM totais. Foram realizados ensaios de remoção de THM por adsorção em diferentes concentrações de carvão ativado em pó (CAP), seguido de processos de coagulação com sulfato de alumínio, floculação, sedimentação e filtração, em reatores estáticos. Os resultados obtidos indicaram que a formação de THM é diretamente proporcional às concentrações de cloro, ácidos húmicos, íon brometo e ao tempo de contato das reações. Os procedimentos de adsorção em CAP, seguido de processos convencionais de tratamento de água, demonstraram remoções de THM das amostras da ordem de até 89%. O aumento da concentração de CAP de 10 para 150 mg/L, e do tempo de contato de adsorção de 60 para 120 minutos, contribuiu para os melhores desempenhos nos experimentos realizados. As técnicas de detecção de THM por cromatografia gasosa e por espectrofotometria apresentaram resultados diferentes nas condições destes ensaios / Abstract: The present research evaluated, in laboratory scale, the formation of trihalomethanes (THM) produced in oxidation reactions, with free chlorine, of water samples with humic acids, in different concentrations and reaction time. This research also studied the presence of the bromide ion, to evaluate, qualitatively and quantitatively, the different species of THM produced. Trihalomethanes detection was comparatively investigated through two analytical techniques. The gaseous chromatography, indicated for the analysis of such molecules, resulted in the quantification of chloroform, dichlorobromomethane, dibromochloromethane and bromoform. The spectrophotometric technique was evaluated as an alternative methodology to the first one, allowing the expression of the results only in total THM. Static reactors were used to carry out assays of THM removal by adsorption in different concentrations of powdered activated carbon (PAC), followed by coagulation processes with aluminium sulphate, flocculation, sedimentation and filtration. The results indicated that THM formation is directly proportional to the concentrations of chlorine, humic acids, bromide ion and reaction time. The procedure of PAC adsorption, followed by conventional processes of water treatment were effective, showing THM removal from the samples of up to 89%. The increase in PAC concentration from 10 to 150 mg/L, and adsorption reaction time from 60 to 120 minutes, resulted in the best performances. The methodologies for THM based on gaseous chromatography and espectrophotometric presented different results in the laboratory conditions of these assays / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil

No description available.

MESHWR / Department of Hydrology and Water Resources / Siloam, a village in the Northern province of South Africa has groundwater reportedly characterised by concentration of fluoride greater than 1.5 mg/L permissible limit. Regional investigation has been done to determine the possible fluoride sources in the northern province of South Africa, but no localised investigation has been documented. The World Health Organization and South Africa National Standard permissible limit is 1.5 mg/L for a duration of time. Therefore, this study focuses on investigating the sources of fluoride in the groundwater of Siloam village in response to reported high incidences (80%) of dental fluorosis in Siloam village. This study also elaborates more on the hydrochemical and geochemical processes favouring the release of fluoride into the groundwater of Siloam village. Two (2) surface rocks, one (1) surface clay deposit, twelve (12) borehole cuttings and four (4) groundwater samples were used for this study. Temperature, total dissolved solids (TDS), conductivity (EC) and pH of the groundwater were determined using a combined multimeter because these parameters are proxy indicators of geogenic influence on groundwater fluoride concentration. Total fluoride in the groundwater samples and the leachates obtained during a leaching experiment were determined using Ion Chromatograph (IC) and Fluoride Ion Selective Electrode (FISE). X-ray fluorescence spectrometry is the most preferred method for rock analysis by earth scientists because it is faster and does not require ambiguous training on the part of the analyst, therefore, it is mostly the standard methods used in whole rock chemistry. Elemental composition and mineralogy were determined using X-ray Fluorescence (XRF) and X-ray diffraction (XRD), respectively. Clay, greywacke, argillaceous sedmients and basalt were analysed. Results obtained indicated that the groundwater fluoride concentration ranges from 3.92 to 4.95 mg/L, which are far above the WHO permissible limit and South African standard. Insitu temperature reading obtained ranges from 25 to 48°C thus classifying the groundwater to be hot and tepid. The groundwater pH ranges from 8.1 to 9.1 which indicates an alkaline water condition. The groundwater conductivity ranges from 330 to 730 μS/cm while the Total dissolved solids ranges from 130.12 to 423.07 mg/L. Groundwater proxy indicators showed geologic sources to be responsible for the high fluoride concentration in the groundwater of Siloam village. Hydrochemical investigation revealead that the mineralisation of groundwater in Siloam village is as a result of rock water interaction and the process of groundwater enrichment is through base ion exchange and reverse ion exchange. The dominant water type in the village was identified to be Na-Cl water type and the abundance of sodium (Na) is due to the heavy weathering of plagioclase of the parent rocks. Total fluoride content of the rocks and soils of the village ranges from 10 to 2000 mg/L. The leachable fluoride, however, ranged in concentration from 0.27 to 14.88 mg/L under induced temperature v and 0.05 to 10.40 mg/L without temperature. Mineralogical investigation revealed the abundance of smectite clay, which is known for its enrichment and leaching of fluoride into groundwater sources, thus, the research question and assumption about the possible source of fluoride and the assumption that fluoride increases downwards towards the aquifer were answered. Leaching experiments identified the main contributors of fluoride to groundwater in Siloam village as smectite clays and the muscovite present in the sandstone, greywacke and basalt. Time based leaching experiment, geochemical modelling and dating of different hydrogeological unit was recommended / NRF