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Estudo hidrodinâmico de floculadores mecanizados aplicados ao tratamento de água /Cestari, Jesus Leonardo. January 2011 (has links)
Resumo: Utilizando-se um floculador mecanizado com quatro câmaras foram realizados ensaios hidrodinâmicos com o traçador cloreto de sódio obtendo-se curvas de distribuição dos tempos de residência (DTR) e os tempos de residência médios para os tempos de residência teórico de 29,54 min, 22,15 min e 14,77 min respectivamente para o floculador operando com 04, 03 e 02 câmaras. Entre as câmaras de floculação havia quatro diferentes posições de passagens, sendo duas em cima "D" e "E" (respectivamente Direita superior e Esquerda superior) e duas embaixo "d" e "e" (respectivamente direita inferior e esquerda inferior). Levando-se em consideração que a entrada de água era realizada na passagem "e", foram combinadas quatro configurações de passagem para floculador de 04 câmaras (eEeEe , eDeDe , edede e eeeee) e uma quinta empregando-se anteparos (e/e/e/e/e). As mesmas configurações foram estendidas ao floculador operando com 03 e 02 câmaras. Procurou-se avaliar nos floculadores, operando sob as diferentes configurações de passagem apresentadas acima, a magnitude dos efeitos dos curtos-circuitos de acordo com os estudos pré- definidos. Tais estudos combinaram o sentido de rotação dos agitadores (sentido alternado e mesmo sentido de rotação ao longo das câmaras) com a constância ou a variação do gradiente de floculação, além de um estudo com os agitadores desligados. Observou-se, após a análise das curvas DTR, que as configurações edede e e/e/e/e/e para floculador de 04 câmaras, estendidas aos floculadores de 03 e 02 câmaras, apresentaram menor incidência de curtos-circuitos que a configuração eEeEe. A colocação do anteparo que gerou a configuração e/e/e/e/e para floculador de 04 câmaras, estendida aos floculadores de 03 e 02 câmaras, mostrou-se uma alternativa... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Using a mechanical flocculator with four flocculation chambers, hydrodynamic tests were conducted using sodium chloride as a tracer resulting in curves of the residence time distribution (RTD) and the mean residence times for the theoretical residence time of 29.54 min, 22.15 min and 14.77 minutes, respectively for the flocculator with 04, 03 and 02 chambers. Between the flocculation chambers had four different positions of passages, two on top "D" and "E" (respectively upper right and upper left) and two down "d" and "e" (respectively lower right and lower left). Taking into account that the entry of water has always been held in the lower left passage "e" for the flocculator with 04 chambers, four different configurations were combined (eEeEe, eDeDe, edede and eeeee) and a fifth employing shields (e/e/e/e/e). The same settings were extended to the flocculator operating with three and two chambers. Was evaluated in flocculation unit, operating under the different configurations of passage, the magnitude of the effects of short circuits according to the studies previously defined. These studies combined the direction of rotation of the agitator with the velocity gradient and a study of the rioters off. Was observed after analysis of the curves RTD, that the settings edede and e/e/e/e/e to flocculators of 04, 03 and 02 chambers, showed a lower incidence of short-circuits that configuration eEeEe. The placement of the bulkhead, which generated the configuration e/e/e/e/e, showcases itself as an efficient alternative only in the absence of agitation, promoted by agitators. Flocculator with 04 chambers, one does not notice the influence of parameters direction of the agitator and the constancy or variation of velocity gradient on the RTD / Orientador: Marcelo Libânio / Coorientador: Tsunao Matsumoto / Banca: Milton Dall'Aglio Sobrinho / Banca: Luiz Di Bernardo / Mestre
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Electrospun Polymeric Nanocomposites for Aqueous Inorganic and Organic Pollutant RemovalJanuary 2018 (has links)
abstract: Electrospinning is a means of fabricating micron-scale diameter fiber networks with enmeshed nanomaterials. Polymeric nanocomposites for water treatment require the manipulation of fiber morphology to expose nanomaterial surface area while anchoring the nanomaterials and maintaining fiber integrity; that is the overarching goal of this dissertation. The first investigation studied the effect of metal oxide nanomaterial loadings on electrospinning process parameters such as critical voltage, viscosity, fiber diameter, and nanomaterial distribution. Increases in nanomaterial loading below 5% (w/v) were not found to affect critical voltage or fiber diameter. Nanomaterial dispersion was conserved throughout the process. Arsenic adsorption tests determined that the fibers were non-porous. Next, the morphologies of fibers made with carbonaceous materials and the effect of final fiber assembly on adsorption kinetics of a model organic contaminant (phenanthrene, PNT) was investigated. Superfine powdered activated carbon (SPAC), C60 fullerenes, multi-walled carbon nanotubes, and graphene platelets were added to PS and electrospun. SPAC maintained its internal pore structure and created porous fibers which had 30% greater PNT sorption than PS alone and a sevenfold increase in surface area. Carbon-based nanomaterial-PS fibers were thicker but less capacious than neat polystyrene electrospun fibers. The surface areas of the carbonaceous nanomaterial-polystyrene composites decreased compared to neat PS, and PNT adsorption experiments yielded decreased capacity for two out of three carbonaceous nanomaterials. Finally, the morphology and arsenic adsorption capacity of a porous TiO2-PS porous fiber was investigated. Porous fiber was made using polyvinylpyrrolidone (PVP) as a porogen. PVP, PS, and TiO2 were co-spun and the PVP was subsequently eliminated, leaving behind a porous fiber morphology which increased the surface area of the fiber sevenfold and exposed the nanoscale TiO2 enmeshed inside the PS. TiO2-PS fibers had comparable arsenic adsorption performance to non-embedded TiO2 despite containing less TiO2 mass. The use of a sacrificial polymer as a porogen facilitates the creation of a fiber morphology which provides access points between the target pollutant in an aqueous matrix and the sorptive nanomaterials enmeshed inside the fiber while anchoring the nanomaterials, thus preventing release. / Dissertation/Thesis / Doctoral Dissertation Engineering 2018
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Conception d'une unité mobile pour le post-traitement d'eau utilisée pendant des opérations d'extinction d'incendie / Design of a mobile post-treatment unit for the water used during fire extinguishmentBaudequin, Clément 28 October 2011 (has links)
L’extinction de feux de liquides inflammables sur des installations industrielles telles que les dépôts de carburant ou les raffineries entraîne l'utilisation de milliers de mètres cubes d'eau, composé majeur des mousses anti-incendie. Ces dernières contiennent généralement des tensioactifs hydrocarbonés ainsi que des tensioactifs fluorés qui se retrouvent dans les eaux d'extinction, ainsi que les suies et les restes de solvants. Les tensioactifs fluorés jouent un rôle clé dans l'efficacité des mousses anti-incendie en raison de leur nature chimique particulière. En raison de la présence des tensioactifs fluorés, le traitement actuel de l'eau d'extinction d'incendie est l'incinération dans des incinérateurs haute température et résistant aux halogènes. Les tensioactifs sont des composés amphiphiles qui ont comme propriétés d'abaisser la tension superficielle de l'eau et de former des agrégats en solution : les micelles. Les tensioactifs peuvent également s'adsorber aux interfaces ainsi qu'aux surfaces solides, et éventuellement y former des agrégats de surface, analogues aux micelles en solution. L’objectif industriel de la présente thèse est de proposer une unité mobile de traitement de ces eaux afin de concentrer les composés fluorés et limiter les volumes à incinérer. Les critères de sélection des procédés que nous avons retenus sont les suivants : compacité, peu ou pas de produits chimiques ou solides nécessaires. L’objectif scientifique de ce travail est de mieux comprendre le comportement de ces composés au cours des procédés d’électrocoagulation/filtration et d’osmose inverse. Des essais préliminaires ont été réalisés et ont permis de choisir les procédés suivant : l'électrocoagulation couplée à la filtration comme prétraitement pour séparer les particules en suspension et les traces d’émulsions éventuelles de la phase aqueuse et l'osmose inverse comme traitement pour concentrer les tensioactifs fluorés. A l'échelle du laboratoire, l'électrocoagulation, permettant le retrait de la matière en suspension, a été optimisée pour des eaux d'extinction d'incendie pilotes et un mécanisme a été proposé. L'efficacité de ce procédé a ensuite été vérifiée sur un pilote industriel. L'osmose inverse d'eaux d'extinction d'incendie pilotes pré-traitées par électrocoagulation/filtration a montré de forts taux de rétention du tensioactif fluoré. Une comparaison de différents matériaux membranaires a été réalisée sur un module d’osmose inverse plan avec des solutions modèles. Des essais de filtration de longue durée, à l’échelle pilote, ont permis de suivre l’évolution de la rétention des tensioactifs et du flux de perméat. Ces données ont été utilisées pour réaliser le dimensionnement d’une unité mobile de post traitement d’eau d’extinction d’incendie. Les perspectives de ce travail sont les suivantes : La prise en charge de la réalisation d’une unité mobile devrait être menée par un partenaire de DuPont de Nemours qu’il reste à identifier. L’étude sur la modification de l’état de surface des membranes est poursuivie dans le cadre d’une nouvelle thèse et permettra à terme de mieux choisir les conditions opératoires de filtration et de nettoyage au cours des procédés membranaires et ainsi d’améliorer les performances du procédé. / Extinguishment of large solvent fire leads to the production of fire fighting water, which are collected thanks to the design of industrial infrastructures. Depending on the nature of the firefighting foam used, the resulting water may require the removal of fluorinated surfactants potentially present. After decantation of the organic phase, fire fighting waters essentially contain surfactants. Surfactants are amphiphilic chemicals having the ability to lower both interfacial and surface tensions by adsorbing in an oriented fashion at interface. Surfactant can form micellar aggregates in solution and on interfaces under certain conditions, and have a pronounced influence on interfacial phenomena. Hence, before considering any water treatment process, interfacial science and surfactant were introduced. This work has a dual purpose. The industrial purpose is to provide an economically viable alternative to water incineration. The foreseen unit will have to be mobile and able to extract fluorinated surfactants from water at a rate of 1-4.5 m3h-1 (20,000 m3 in 4-6 months). The scientific purpose of this work is the study of the behavior of surfactants in the context of water treatment processes. The state of the art of relevant water treatment processes and an experimental screening with real firefighting water permitted to identify two steps as likely to fit the constraints of a mobile unit: electrocoagulationfiltration coupled with reverse osmosis. The electrocoagulation process followed by filtration was applied to pilot, model and industrial firefighting waters. This process was found to remove efficiently the unwanted turbidity from pilot firefighting waters. Current knowledge about the separation mechanisms of small organic molecules in reverse osmosis has been reviewed, and rejection as well as flux decline were related to membrane, solution, and solute properties. Polyamide and cellulose acetate membrane materials were screened in a flat sheet cell. The stabilities of rejection and flux decline were confirmed during longer tests (several days) on an industrial pilot with the most appropriate membrane. A final design study confirmed the possibility to combine electrocoagulation-filtration and reverse osmosis to treat firefighting waters.
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Viabilidade técnica e econômica da regeneração de coagulantes a partir de lodos gerados em estações de tratamento de água. / Technical and economical feasibility of coagulant recovery from water treatment plant sludges.Juliana Gardenalli de Freitas 15 December 2004 (has links)
Esse trabalho teve como objetivo avaliar a viabilidade técnica e econômica da regeneração de coagulantes a partir do lodos gerados em ETA\'s. Foi considerado que o coagulante regenerado será empregado em sistemas de tratamento de esgotos. A regeneração de coagulante consiste basicamente em promover uma alteração no pH do lodo, de forma que os hidróxidos metálicos presentes são solubilizados. A fase líquida com alta concentração de metais é então separada, constituindo o coagulante regenerado. Consequentemente, essa tecnologia propicia a recuperação de um recurso, que é o coagulante, e a redução de lodo. Para a verificação da viabilidade técnica foram realizados ensaios de acidificação em escala de bancada com lodos das ETA\'s Guaraú e Rio Grande, visando o estudo das condições de regeneração, da qualidade do coagulante produzido e do lodo restante. Foi verificado que do ponto de vista técnico a regeneração de coagulantes é uma alternativa possível, gerando um coagulante aproximadamente 100 vezes mais diluído que os comerciais, mas com desempenho satisfatório na aplicação no tratamento de efluentes de reator UASB. As reduções médias de sólidos em suspensão nos lodos utilizados foram de 28% e 53%. A avaliação econômica foi realizada considerando uma ETA com características similares à ETA Rio Grande, com um sistema de regeneração em funcionamento. Foi verificado que considerando as reduções de custos decorrentes da diminuição de lodo a ser tratado e disposto, o custo de produção do coagulante regenerado é muito próximo ao custo do coagulante comercial. Portanto, conclui-se que hoje em dia essa tecnologia deve ser considerada como uma alternativa potencialmente viável dos pontos de vista técnico e econômico para o tratamento e reaproveitamento de lodo de ETA\'s. / The primary goal of this work was to evaluate the technical and economical feasibility of coagulant recovery from water treatment plant sludges, considering that the recovered coagulant is going to be used in wastewater treatment plants. The coagulant recovery technology consists in change the sludge pH, in order to solubilize the present metal hydroxides. The liquid phase with high metals concentrations is then separated, becoming the recovered coagulant. This technology provides a resource recovery, which is the coagulant, and also a reduction in the amount of sludge that needs to be treated and disposed. To verify the technical feasibility, acidification bench tests were conduced using sludges from Guaraú e Rio Grande water treatment plants, in order to study the regeneration conditions, the recovered coagulant quality and the remaining sludge. From the technical point of view, it was verified that coagulant recovery is a possible alternative, producing a coagulant 100 times more diluted than the commercial coagulant, but with a satisfactory behavior in the treatment of UASB reactor effluent. The suspended solids average reductions in the Rio Grande and Guaraú water treatment plants sludges were 53% and 28%, respectively. The economical evaluation was done using the results obtained in the bench tests and considering a water treatment plant similar to Rio Grande. It was verified that considering the costs decrease due to the sludge reduction, the recovered coagulant production cost was very similar to commercial coagulants cost. Thus, it was concluded that nowadays this technology must be considered as a potential alternative for the treatment and reuse for water treatment plant sludges, regarding to the technical and economical aspects.
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Comparative Economic Evaluation of Water Treatment Station for Treating Water Maranguape two distinct watersheds: dams Acarape Middle and GaviÃo / AvaliaÃÃo econÃmica comparativa da estaÃÃo de tratamento de Ãgua de Maranguape tratando Ãgua de dois distintos mananciais: AÃudes Acarape do Meio e GaviÃoAbraÃo Evangelista Sampaio 24 January 2014 (has links)
Por causa do aumento expressivo da poluiÃÃo ambiental ocorrido nas Ãltimas dÃcadas, a eutrofizaÃÃo artificial vem recebendo maior atenÃÃo por parte da comunidade cientÃfica e concessionÃrias de saneamento. Devido a esse problema, houve considerÃvel elevaÃÃo nos custos de tratamento da Ãgua para adequar aos padrÃes exigidos pela Portaria do MinistÃrio da SaÃde (2914/2011). O presente trabalho levantou, avaliou e comparou, entre janeiro de 2010 a dezembro de 2012, os custos de produÃÃo de Ãgua na EstaÃÃo de Tratamento de Ãgua (ETA) que abastece a cidade de Maranguape, considerando as captaÃÃes nos aÃudes GaviÃo e Acarape do Meio. Neste contexto, procurou-se o entendimento dos processos atravÃs da analise dos custos com Ãgua bruta, energia elÃtrica, produtos quÃmicos, operaÃÃo e perda de Ãgua nas lavagens dos filtros. A pesquisa mostra que a mÃdia dos custos de produÃÃo de Ãgua na saÃda da ETA à de R$ 0,26/m utilizando como manancial de abastecimento o aÃude Acarape do Meio e R$ 0,44/m quando utilizado o aÃude GaviÃo. Observou-se que estes custos sÃo fortemente influenciados pela diferenÃa das tarifas da Ãgua bruta, sendo o custo da Ãgua vinda do aÃude GaviÃo trÃs vezes maior que a Ãgua do aÃude Acarape do Meio. Observou-se que, apesar de ter uma pior qualidade, o que influencia nas perdas por lavagem e no aumento do consumo de produtos quÃmicos, a Ãgua do aÃude Acarape do Meio permite uma reduÃÃo mÃdia de 66% dos custos de produÃÃo de Ãgua tratada quando comparado com os meses em que a ETA Maranguape à alimentada pelo aÃude GaviÃo. / Because of the significant increase in enviromental pollution that happened in the last decades, the artificial eutrophication has received a bigger attention of cientific comunity and concessionaires sanitation. Because of this problem there was a considerable elevation in the water treatment costs to conform to the standards required by the PortÃria do MinistÃrio da SaÃde (2914/2011). This work showed, evaluated and compered, between january of 2010 and december of 2012, the cost of water production in the EstaÃÃo de Tratamento de Ãgua (ETA) that supplies Maranguape city, considering the catchment in the GaviÃo and Acarape do Meio weirs. In this context, sought to understand the process through analysis of gross water costs, eletric energy, chemicals, operation and loss of water in the wash filters. The reserch shows that the average cost of water production at the exit of the ETA is R$ 0,26/m using as supply fountainhead the Acarape do Meio weir and R$ 0,44/m when used the GaviÃo weir. It was noted that these costs are strongly influenced by the rates of gross water, being the cost of water that came from GaviÃo weir three times bigger than the water of Acarape do Meio weir. It was noted that, despite having a lower quality, what influences in the washing losses and increased consumption of chemicals, the water of Acarape do Meio weir allows an average reduction of 66% of the production costs of treated water when compared with the months in which the ETA Maranguape is fueled by the GaviÃo weir.
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Desinfeccao de efluentes de sistemas de tratamento de esgotos sanitarios por meio da radiacao ultravioletaCAMACHO, PAULO R.R. 09 October 2014 (has links)
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Avaliação de equipamento tipo jato cavitante para inativação de Escherichia Coli empregando múltiplos jatos / Evaluation of a cavitating jet apparatus for inactivation of Escherichia coli using multiple jetsAssis, Maiara Pereira, 1987- 05 June 2014 (has links)
Orientadores: José Gilberto Dalfré Filho, Ana Inés Borri Genovez / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-25T02:40:27Z (GMT). No. of bitstreams: 1
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Previous issue date: 2014 / Resumo: As discussões acerca da escassez de água e da sua qualidade para consumo humano são primordiais no contexto da gestão dos recursos hídricos. A água lançada na forma de esgoto doméstico e industrial nos corpos hídricos representa uma ameaça à saúde pública. Contudo, a qualidade da água pode ser melhorada controlando-se a poluição e aprimorando-se as técnicas de inativação de microrganismos e de degradação de compostos, que consistem na destruição de microrganismos e de compostos químicos excedentes. Uma das técnicas alternativas de inativação e degradação é empregar o fenômeno da cavitação. A cavitação desenvolve altas tensões de cisalhamento no interior do fluido e, além do mais, pode envolver a liberação de radical hidroxila, que auxiliam na oxidação de compostos presentes na água. O objetivo deste trabalho foi desenvolver um equipamento tipo jato cavitante para a inativação de Escherichia coli, empregando uma nova configuração com múltiplos jatos. A nova configuração do equipamento foi testada e comparada com a configuração existente no Laboratório de Hidráulica e Mecânica dos Fluidos, na busca de uma eficiência ótima. Os resultados indicam uma dependência da inativação com a pressão do equipamento e a configuração de bocais. Um bocal com orifício único e pressões menores (até 15,00 MPa) ou um sistema de bocais tridimensional e pressões maiores (em torno de 30,00 MPa) obtiveram as melhores taxas de inativação. As eficiências energéticas do equipamento tipo jato cavitante para cada taxa de inativação foram verificadas. Neste caso, as melhores alternativas dependem do tempo de inativação requerido. O equipamento tipo jato cavitante mostrou-se como uma alternativa viável para a inativação de Escherichia coli e que pode ser empregado com outras técnicas de inativação / Abstract: Discussions on the scarcity of water and its quality for human consumption are keys for the water resources management. The water released as domestic and industrial sewage in water bodies poses a threat to public health. However, the water quality can be improved by controlling pollution and by improving the techniques of inactivation of microorganisms and degradation of compounds, which consists of destruction of microorganisms and degradation of chemicals. One of the alternative techniques for inactivation and degradation is to employ the phenomenon of cavitation. Cavitation develops shear stress within the fluid and, besides, may involve the release of hydroxyl radicals, which assist the oxidation of the compounds present in the water. The objective of this study was to develop a cavitating jet apparatus to inactivate Escherichia coli, using a new configuration with multiple jets. The new configuration of the equipment was tested and compared with the existing configuration at the Laboratory of Hydraulics and Fluid Mechanics in the search for the optimal efficiency. The results indicated a dependence of inactivation with the pressure of the equipment and the configuration of nozzles. A single orifice nozzle and lower pressures (up to 15.00 MPa) or a system of three-dimensional nozzles and higher pressures (around 30.00 MPa) obtained the best inactivation rates. The energy efficiency of the cavitating jet apparatus in the rate of inactivation was verified. In this case, the best alternatives depend on the time required for inactivation. The cavitating jet apparatus proved to be a viable alternative to the inactivation of Escherichia coli and can be used along with other inactivation techniques / Mestrado / Recursos Hidricos, Energeticos e Ambientais / Mestra em Engenharia Civil
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An Assessment of Constructed Wetland Treatment System Cells: Removal of Excess Nutrients and Pollutants from Municipal Wastewater in Lakeland, FloridaKlinepeter, Molly 26 June 2017 (has links)
Wastewater treatment wetlands are proven valuable alternatives to the treatment of wastewater in a more natural environment. These wetlands can be natural or constructed, and come in a variety of types and sizes. The purpose of this study was to determine the efficiency of water treatment for nutrients and pollutants utilized by the City of Lakeland in treating their municipal wastewater by wetland treatment system cells. This study is important in order to ensure the successful use of the wetland, as well as to determine the impacts previous phosphorus mining use may have on the effectiveness of treatment. Following FDEP standard operating procedures, this study monitored various water quality parameters for three consecutive summer months. The wetland as a whole varied in the removal of nutrients. The wetland was best at decreasing concentrations of TN and TP, at eighty-three percent and fifty-four percent, respectively, when compared to other parameters. This study shows how municipal wastewater is beneficially treated by wetland treatment system cells to produce viable water resources that can be reused in order to promote sustainable uses going into the future.
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The hydrolysis of aluminium, a mass spectrometric studySarpola, A. (Arja) 18 September 2007 (has links)
Abstract
This thesis is focused on the hydrolysis of aluminium, the polymerisation of the hydrolysis products, and how these can be monitored by mass spectrometric methods. The main aim of this research is to figure out how the aqueous speciation of aluminium changes as a function of pH (3.2–10), concentration (1–100 mM), reaction time (1s–14d), and counter anion (Cl-, SO42-, HCOO-). The method used was electrospray mass spectrometry. The results showed more variable speciation than those suggested earlier. The main species were Al2, Al3, and Al13, which were found in all of the conditions under scrutiny. The effect of pH was the most remarkable of all the parameters researched. The formation of large highly charged complexes was strongly dependent on it. Also the Al-concentration in the bulk solution had a clear effect on speciation: in dilute solutions there were more protonated ligands and less attached counter anions. This could mean that the species in more diluted bulk solutions had fewer different states of charge. Reaction time caused only minor changes to speciation in the initial pH: there was slightly more variation of a certain sized species in the aged solution. In elevated pH, the birth of important Al13 oligomers was time dependent. The effect of the counter anion was tremendous. In a chloride environment the speciation was rich and diversified. With sulphate the speciation was limited to solid- like compounds, and the variation of single-sized species was almost lacking. The formate as a counter anion caused most surprising results; the charge of aluminium in some studied complexes was lowered from the common 3+ to 1+. If this reaction also occurs in natural circumstances, the uses of aluminium formate would be wide. The results can be utilised in following the progress of dissolution, the mobilization and toxicity of aluminium in natural waters, as well as in water purification, and in reaching minimal chemical contamination levels in sludge as well as in aqueous waste.
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Evaluating and Avoiding Risk Tradeoffs in Water TreatmentGingerich, Daniel Beryl 01 August 2017 (has links)
Treating water in order to reduce human and environmental risks requires the use of electricity and chemicals, the generation of which creates emissions of air pollutants such as NOx, SO2, PM2.5, and CO2. Emissions of air pollutants establishes a health and environmental risk tradeoff between air and water pollution. Addressing air-water tradeoffs by adopting a one environment framework requires new methods for quantifying these tradeoffs, new technologies to minimize air-water tradeoffs, and new tools for decision makers to incorporate these tradeoffs into compliance decisions. In my thesis, I develop methods for quantifying damages from air emissions associated with water treatment; assess the feasibility of forward osmosis (FO), a technology which holds the promise to avoid air-water tradeoffs; and create a tool to holistically assess compliance with air and water emission standards for coal-fired power plants (CFPPs). I start my thesis by creating a method to quantify the damages caused by the air emissions that resulting from the treatment of drinking water (Chapter 2), municipal wastewater (Chapter 3), and flue gas desulfurization (FGD) wastewater (Chapter 4). These studies use life-cycle models of energy and chemical consumption for individual water treatment unit processes in order to estimate embedded emissions of criteria air pollutants and greenhouse gasses per cubic meter of treated water. Damages from these additional air emissions are assessed and incorporated into benefit-cost analyses. I find that for drinking water rules, the net benefit of currently implemented rules remains positive but the promises of net benefits for some proposed rules are conditional on the compliance technology that is selected. For municipal wastewater, I find that while there are ~$240 million (in 2012 USD) benefits in air emission reduction from installing biogas-fueled electricity generation nationwide, there are several states where biogas-fueled electricity creates more air emissions than it displaces. For FGD wastewater treatment, I find that complying with the effluent limitation guidelines has an expected ratio of benefits to cost of1.7-1.8, with damages concentrated in regions with large chemical manufacturing industries or electricity grids that are heavily reliant on coal. In the next part of the thesis, I assess the techno-economic feasibility of power plant waste heat driven FO to reduce the air emissions associated with FGD wastewater treatment. In Chapter 5, I assess the quantity, quality and the spatial and temporal availability of waste heat from US coal, nuclear, and natural gas power plants. I find that while 18.9 billion GJ of potentially recoverable waste heat is discharged into the environment, only 900 million GJ of that heat is from the flue gas and is at a temperature high enough to drive water purification using forward osmosis (FO). In Chapter 6, I build a model of FO to assess its thermal energy consumption and find that the 900 million GJ of waste heat produced at coal and natural gas power plants is sufficient to meet their boiler feedwater and FGD wastewater treatment needs. In Chapter 7, I incorporate cost into the energy consumption model of FO, and conclude that treatment of FGD and gasification wastewater using waste heat driven FO is economically competitive with mechanical vapor recompression. In Chapter 8, I create an energy-balance model of a CFPP and nine environmental control technologies for compliance with FGD wastewater and carbon capture regulations. I use this model to maximize plant revenue at the National Energy Technology Laboratory’s 550 MW model CFPP without carbon capture. I find that revenue is maximized by using residual heat for water treatment or carbon capture. If both carbon capture and zero liquid discharge water treatment regulatory standards are in place, I conclude that the plant maximizes revenue by allocating residual heat and steam to amine-based carbon capture and electricity to mechanical vapor recompression for FGD wastewater treatment.
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