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Consortium algues-bactéries des lagunes à haut rendement algal : évaluation des performances, devenir des nutriments des eaux usées et conception à base de modèles expérimentaux et numériques / Algal-bacterial consortium in high rate algal pond : evaluation of performances, wastewater nutrient recovery and experimental and numerical models based designPham, Le Anh 13 September 2018 (has links)
La présente thèse porte sur des travaux expérimentaux et de modélisation visant à étudier les processus bactériens et algaux au sein d’une lagune a haut rendement algal (HRAP). Un système pilote HRAP a été construit et les impacts des différentes conditions opérationnelles sur l’hydrodynamique et le transfert gaz/liquide du pilote ont été étudiés. De plus, le rapport d'inoculation optimal entre les algues et les bactéries (Al-Bac) a également été étudié. La biomasse Al-Bac a ensuite été inoculée dans le système HRAP pour une évaluation à long terme du traitement des eaux usées et de la récupération des nutriments. Le HRAP dans cette étude peut être appliqué en traitement secondaire de eaux usées ou comme étape primaire éliminant rapidement les charges élevées de DCO et de TKN des retour en tête de digesteurs anaérobies (centrats). Les résultats expérimentaux obtenus ont également été utilisés pour calibrer et valider des modèles de type « boîte noire » et mécanistes. Les deux modèles peuvent décrire le fonctionnement à long terme du système. Le premier permet ainsi d'évaluer rapidement les performances du système ainsi que de le dimensionner, tandis que le second simule avec succès les résultats à long (général) et à court (détaillé) terme. L'étape suivante devrait être l'application du système à grande échelle. / The thesis focused on both experimental and modeling works aiming to investigate the algal bacterial processes in High-Rate Algal Pond (HRAP) system. A pilot HRAP system was built and the impacts of different operational conditions on hydraulic and gas transfer rate of the pilot were investigated. Moreover, optimal inoculation ratio between algae and bacteria (Al-Bac) was also studied. The Al-Bac biomass was theninoculated in the HRAP system for long term assessment of wastewater treatment and nutrient recovery. The HRAP in this study can be applied for secondary treatment application or as a primary step removing rapidly high loads of COD and TKN from centrate wastewater. Experimental results obtained were also employed in calibrating and validating black box and comprehensive algal bacterial models. Both models coulddescribe the system in long term. The former was adequate for giving quick assessment of the system performance as well as sizing application while the latter successfully simulated the results both in long (general) and short (detailed) time scale. A next step should be applying the system in large scale.
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Emprego da flotação lamelar de alta taxa e convencional como pós-tratamento do efluente de sistema constituído de reator anaeróbio seguido de reator aeróbio tratando esgoto sanitário / Lamella design (high rate) and conventional flotation units applied to the post-treatment of the effluent from a system made up anaerobic reactor followed by aerobic reactor treating domestic sewageMoretti, Renata Cristina 20 May 2005 (has links)
O presente trabalho teve como objetivo o estudo da potencialidade de aplicação da flotação por ar dissolvido (FAD) lamelar (de alta taxa) e convencional como parte final de sistema de tratamento sequencial de esgoto sanitário, constituído de reatores anaeróbios de manta de lodo (UASB) seguidos de tanque de aeração. O trabalho, desenvolvido na Estação de Tratamento de Esgotos Jardim das Flores da cidade de Rio Claro, foi dividido em três etapas. Na primeira etapa, realizada com equipamento Flotateste, foram investigados os valores mais adequados de dosagens de polímero sintético catiônico, amido de araruta, cloreto férrico e associações entre cloreto férrico e polímero ou amido de araruta, de razão ar/sólidos (A/S), bem como de tempo e gradiente de mistura rápida e de floculação. Nessa etapa, os melhores desempenhos da FAD foram obtidos com o emprego de polímero catiônico, tanto isoladamente quanto associado ao cloreto férrico, sendo esta última condição imprescindível para maior remoção de fósforo. A flotação de liquor misto utilizando apenas o cloreto férrico como coagulante, apresentou desempenho extremamente insatisfatório, com a formação de flocos com características ruins de flotabilidade. Além disso, observou-se que a flotação desse tipo de efluente requisitou condições mais amenas de mistura, sendo que, em muitos casos, os melhores resultados foram obtidos mediante a eliminação da mistura rápida ou da floculação. Nas segunda e terceira etapas, realizadas com unidades piloto de flotação lamelar de alta taxa (FADAT) e convencional, respectivamente, e empregando apenas polímero como auxiliar de floculação/flotação (dosagem em torno de 1 g de polímero/kg de SST), foram investigados os valores mais adequados de Taxa de Aplicação Superficial (TAS), Taxa de Aplicação de Sólidos (TS) e quantidade de ar fornecida à flotação, calculada através da razão A/S ou da dosagem de ar (Dar), em g de ar/'M POT.3' de esgoto afluente, dependendo da concentração de sólidos suspensos totais afluentes à flotação (SSTafl). Através dos resultados dos ensaios pôde-se observar que a razão A/S é mais adequada para o cálculo da quantidade de ar na flotação de suspensões concentradas (SSTafl acima de 1100 mg/L no presente estudo), ao passo que Dar é mais representativo no caso da flotação de suspensões diluídas. Empregando a unidade FADAT, alimentada com liquor misto de tanque de aeração em boas condições de biofloculação, foi possível obter resultados satisfatórios para TAS de até 350 'M POT.3'/'M POT.2'.dia e TS entre 120 e 250 kg de SST/'M POT.2'.dia, desde que fornecida quantidade adequada de ar ao processo (Dar na faixa de 15,0 a 18,0 g de ar/'M POT.3' de afluente), para SSTafl entre 800 e 1100 mg/L. Na flotação lamelar de alta taxa, constatou-se que o bom desempenho esteve diretamente relacionado a baixos valores de SSTafl. As recomendações para a flotação com unidade de FAD convencional tiveram que ser mais conservadoras, devido às condições ruins de biofloculação apresentadas pelo liquor misto do tanque de aeração durante a realização da terceira etapa do trabalho. Nesses ensaios, os resultados mais satisfatórios foram obtidos com o emprego de TAS em torno de 200 'M POT.3'/'M POT.2'.dia, TS menor que 200 kg de SST/'M POT.2'.dia e A/S em torno de 0,020 (Dar de 21,0 g de ar/'M POT.3' de afluente), para SSTafl em torno de 1400 mg/L / The aim of this research was the study of the lamella design (high rate) and conventional dissolved air flotation (DAF) process potentiality of application as the final part of a domestic sewage sequential treatment system made up anaerobic reactors (UASB) followed by aeration tank. The work, developed at the Jardim das Flores WWTP of Rio Claro city, was separated in three phases. In the first phase, using the flotatest apparatus, the most suitable values of chemical (synthetic cationic polymer, arrow-root starch, ferric chloride and ferric chloride combined with polymer or arrow-root starch) dosages, air to solids ratio (A/S), as well as rapid mix and flocculation time and mean velocity gradient values, were investigated. In this phase, the best DAF performances were obtained with the application of cationic polymer, alone and associated to ferric chloride. The use of ferric chloride was essential to obtain better phosphorus removal results. The mixed liquor flotation using ferric chloride alone as primary coagulant presented extremely unsatisfactory performance, with the formation of flocks showing bad characteristics of flotability. Moreover, it was observed that flotation of this kind of effluent had requested gentler mixture conditions. In many cases, the best results were obtained by means of rapid mix or flocculation step elimination. In the second and third phases, using the lamella design and conventional flotation units respectively and cationic polymer as the only flocculation/flotation aid (dosage around 1 g of polymer/kg TSS), the most suitable values of Overflow Rate (OR), Solids Application Rate (SAR) and amount of air supplied to the flotation process, expressed as the A/S ratio or air dosage (AD, in g of air/'M POT.3' of influent) depending on influent total suspended solids concentration (TSSinfl), were investigated. The flotation essays results showed that the A/S ratio is more suitable for the air supply estimation in flotation of concentrated suspensions (TSSinfl above 1100 mg/L in this study). Contrarily, the parameter AD is more representative in cases of flotation of diluted suspensions. Using the lamella design unit, fed with aeration tank mixed liquor presenting good bio-flocculation conditions, it was possible to obtain adequate results applying OR as high as 350 'M POT.3'/('M POT.2'.day) combined with SAR values between 120 and 250 kg of TSS/('M POT.2'.day), since the adequate amount of air has been provided for the process (AD values between 15,0 and 18,0 g of air/'M POT.3' of influent), for TSSinfl between 800 and 1100 mg/L. For the lamella flotation, it was noticed that the best performance has been directly associated to lower values of TSSinfl. The recommendations for flotation using the conventional DAF unit had to be more conservative, taking into account the poor bio-flocculation conditions presented by the mixed liquor during the third phase of work. In theses essays, the more adequate results were obtained by applying OR around 200 'M POT.3'/('M POT.2'.day), SAR under 200 kg of TSS/('M POT.2'.day) and A/S ratio around 0,020 (AD of 21,0 g of air/'M POT.3' of influent), for TSSinfl around 1400 mg/L
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Produção de biogás em reator anaeróbio de alta taxa alimentado com a fração líquida de esterco bovino peneirado / Biogas production in anaerobic high-rate reactor fed with the liquid fraction of cattle manureVidal, Adriano Gasparini 19 June 2015 (has links)
O objetivo desse trabalho foi o de avaliar o desempenho de um reator anaeróbio híbrido de alta taxa (AHHR), contendo biomassa imobilizada em leito ordenado, alimentado com a fração líquida de esterco bovino, na produção de biogás. No estudo, foi utilizado um reator anaeróbio de fluxo ascendente de 12,4 L de volume total (9,2 L de volume útil) com leito ordenado composto por hastes de espuma de poliuretano (PU). O leito ordenado utilizado possuía 32 hastes de espuma de 1,25 cm2 de seção com 50,0 cm de comprimento, posicionadas verticalmente no interior do reator. A alimentação do reator e a recirculação foram realizadas por meio de bombas dosadoras de diafragma. O reator operou na faixa mesofílica de temperatura (de 20 a 40 °C) sem a utilização de mecanismos de controle de temperatura. Foram testadas 7 condições operacionais diferentes, variando o tempo de detenção hidráulica (TDH), carga orgânica volumétrica (COV) aplicada e a utilização de recirculação interna. Para cada fase operacional, foram avaliadas a remoção de matéria orgânica e a produção de biogás. O sistema apresentou elevada remoção de matéria orgânica operando com TDH de 3 e 1d, respectivamente, com valores médios de remoção de DQO de 79 % e 71 %. O biogás produzido pelo reator apresentou concentração de metano de 57,6 ± 0,5 % e não foi detectada a presença de sulfeto. A maior produção média de metano foi de 1,676 L CH4/d, obtida com COV de 20 kg DQO/m3.d e TDH de 1d, enquanto a maior produção relativa de metano foi de 0,023 L CH4./ g SV.d, obtida com COV de 5 kg DQO/m3.d e TDH de 1d e recirculação. A relação entre alcalinidade intermediária e parcial teve valor médio de 0,32, oscilando na maior parte do tempo entre 0,27 e 0,33, indicando a estabilidade do processo de digestão anaeróbia. Os resultados obtidos indicaram o potencial satisfatório do AHHR para a remoção de matéria orgânica e produção de biogás a partir da fração líquida do esterco bovino nas condições operacionais testadas na pesquisa. / This study aimed at evaluating the biogas production for electricity generation performance of an anaerobic high-rate hybrid reactor (AHHR), containing immobilized biomass in structured-bed, fed with the liquid fraction of cattle manure. In this study, it was used an upflow 12,4 L anaerobic reactor (9,2 L working volume) with structuredbed composed by 32 PU foam stripes (1,25 cm2 cross section and 500 mm length) vertically fixed inside the reactor. The reactor feeding and internal recirculation was made by diaphragm metering pumps. The reactor operated at mesophilic temperature (20 - 40 °C) without temperature control system. Different operating conditions were tested (7 stages), changing hydraulic retention time (HRT), organic loading rate (OLR) and recirculation use. COD removal and biogas production were evaluated for each operational condition. The system resulted in high COD removal operating with HRT of 3 and 1d, respectively, with average COD removal of 79 % and 71 %. Produced biogas had 57,6 ± 0,5 % of methane and no sulfide. The highest average volumetric methane production was 1,676 L CH4, obtained with OLR of 20 kg COD/m3.d and 1d HRT, and the highest methane yield was 0,023 L CH4/ g VS obtained with OLR of 5 kg COD/m3.d, 1d HRT and recirculation. The intermediate and partial alkalinity relation had an average value of 0,32, varying most of the time between 0,27 and 0,33, indicating the anaerobic digestion process stability. The results indicated the decent COD removal and biogas production using the AHHR fed with the liquid fraction of cattle manure at the operation conditions used in this study.
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Concepção e avaliação do desempenho de um reator anaeróbio de manta de lodo dotado de agitação com jatos e decantador de alta taxa tratando esgoto sanitário / Design and performance evaluation of an upflow anaerobic sludge blanket provided with agitation jets and high rate sedimentation treating domestic sewageSilva, Rodrigo Soares Garcia da 24 April 2015 (has links)
Os reatores UASB (upflow anaerobic sludge blanket reactors) foram um marco histórico no tratamento de efluentes ao propiciar alta retenção de sólidos e boa mistura entre biomassa e afluente. Apesar de os reatores com a concepção original dos UASB serem usados com sucesso em muitas estações de tratamento de esgoto, algumas questões relacionadas a sua operação, construção e manutenção ainda prevalecem. Sendo assim, novas configurações baseadas na concepção tradicional de reatores de manta de lodo podem simbolizar novas tentativas para sanar essas questões. Neste contexto, uma configuração que emprega manta de lodo, objetivando principalmente a eliminação dos separadores trifásicos e adoção mistura com jatos, é aqui proposta, almejando simplificar a distribuição/mistura do esgoto afluente. A pesquisa foi, assim, realizada primeiramente em escala de bancada para determinar do gradiente de velocidade médio necessário para suspensão de sólidos, resultando em valores favoráveis de até 20 s-1. Na segunda fase, uma instalação piloto de 2,69 m3, construída em acrílico, foi utilizada para o estudo das características do jato e dos bocais, e do regime de mistura proporcionado pelo mesmo. Com auxílio das informações obtidas na primeira e segunda fases, a terceira fase do experimento abrangeu a reforma de um reator UASB tradicional, em escala piloto de 20,8 m3, para a implantação desse novo sistema de tratamento: removeram-se os sistemas para coleta de gases e de distribuição de fundo e implantou-se alimentação intermitente por meio de jatos, além de unidade de decantador de alta taxa. Em essência, o novo sistema foi dividido em duas zonas distintas: uma para as reações e outra provida de decantação laminar para a remoção de sólidos suspensos. Na primeira zona, a entrada de esgoto sanitário deu-se por meio de bocal que proporcionou jato para mistura da manta de lodo através da carga manométrica fornecida por reservatório elevado. A velocidade de entrada no reator e o alcance do jato puderam ser determinados, constatando-se que o número de pontos de entrada no reator pode ser reduzido (em relação ao número de pontos recomendados tradicionalmente: 2 a 4 m2, por ponto). O gradiente de velocidade aplicado durante cada jato (com 30 segundos de duração) foi de 16,6 s-1. Para o reator da terceira fase, na fase estável da operação, obteve-se eficiência de remoção de 52,79%, 70,90 % e 47,00% para DQO, DBO e SST, respectivamente. Adicionalmente, avaliou-se o uso de filtro rápido de camada única de areia para o pós-tratamento do efluente do reator anaeróbio, cujas remoções de DQO, SST e Turbidez (para taxa de aplicação de 100 m3.m-2.dia-1) foram de 54,94%, 84,44% e 81,71% respectivamente. Concluiu-se, desta forma, a viabilidade da operação do reator de manta de lodo com alimentação intermitente e sem necessidade de instalação do sistema separador trifásico. / In spite of reactors with the original design of UASB are successfully used in many wastewater treatment plants, some issues regarding the operation, construction and maintenance of these reactors still prevail. Thus, new configurations based on the traditional conception of sludge blanket reactors may signify new tries to solve these issues. In this context, this research proposes a new configuration, using sludge blanket, mainly aiming at the elimination of the three-phase separators and adoption of a mixture through jets in order to simplify distribution / mixing of the influent. Therefore firstly a bench scale study was conducted to determine the required average velocity gradient for suspension of solids, resulting in favorable values up to 20 s-1. In the second phase, a 2.69 m3 pilot plant was built in acrylic to study the characteristics of the jet and the nozzles, and the resulting mixing state. After this stage, and with the contribution of information obtained in the earlier stages, a traditional pilotscale UASB reactor of 20.8 m3 was adapted for the implementation of this new treatment system: the systems for gas collection and distribution of background were removed, and a high-rate sedimentation unit and intermittently feed through jets were introduced. In essence, the new system has been divided into two distinct zones: one for reactions and other provided of laminar decantation to remove suspended solids. In the reaction zone the entry of sewage was given through jet for mixing the sludge blanket. The mixing energy was provided by jet stemmed on an elevated tank, where the sewer was accumulated. The jet range and entry velocity into the reactor could be determined, noting that the number of entry points in the reactor can be reduced (relative to the number of points traditionally recommended: 2 to 4 m2 per point). The velocity gradient applied during each jet (with a 30 seconds duration) was 16.6 s-1. The pilot-scale reactor (third phase), in stable-phase operation, got a removal efficiency of 52.79%, 70.90% and 47.00% for COD, BOD and TSS, respectively. Additionally, were evaluated the use of unique coating rapid sand filter to the post-treatment of the effluent in the anaerobic reactor. The removals obtained for COD, TSS and Turbidity (for application rate of 100 m3.m-2.dia-1) were 54.94%, 84.44% and 81.71% respectively. It was concluded, therefore, the viability of the sludge blanket reactor operation with intermittent feed and without threephase separator system installation.
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Design and performance evaluation of an anaerobic sludge blanket reactor with mechanical mixing system and a high-rate settler treating domestic wastewater / Concepção e avaliação do desempenho de um reator anaeróbio de manta de lodo dotado de agitador mecânico e decantador de alta taxa tratando esgoto sanitárioPessotto, Bruno 24 April 2015 (has links)
The UASB (Upflow Anaerobic Sludge Blanket) reactor, developed by Prof. Gatze Lettinga and his colleagues in the Netherlands more than thirty years ago, is successfully employed in many sewage treatment plants in countries with tropical and subtropical climate. However, are still reported serious operational issues related to the three-phase separators and problematic aspects involving the complexity of its influent distribution system. The focus of this research was to simplify the introduction and dispersion of the sewage in the reactor as well as enhancing the sludge retention, by replacing the characteristic piping system for a mechanical mixing apparatus and substituting the (conventional) three-phase separators by a high-rate settler, respectively. In essence, it was proposed a system partitioned into two distinct regions: one for reaction (i.e. anaerobic digestion of organic matter), in which the sludge blanket was mechanically mixed through the action of a rotating impeller, and another for the removal of suspended solids by the use of a lamella plate clarifier; a sludge recirculation system was also implanted, to pump the settled biomass back to the digestion compartment. The research was subdivided into three main phases: in the first two phases, bench-scale experiments were performed in order to obtain basic data for the design of the mechanical mixing and sedimentation devices, while the third phase consisted of the application of these technologies in a pilot-scale system with total volume of 20.8 m3 (comprised of a 17.0 m3 digestion chamber and a 3.8 m3 compartment for solids removal), as well as its performance assessment. During the development of the research, domestic sewage was applied to feed the experimental system, which was located at the School of Engineering of São Carlos (Campus I) in São Carlos (São Paulo State, Brazil). Throughout the period of effective operation, which lasted 130 days, four distinct operating modes were tested (characterized by intermittent mixing and varying hydraulic loading rates, ranging between 27.6 and 66.5 m3.d-1) and the system reached maximum removal efficiencies of BOD, COD and TSS at rates of 82%, 72% and 83%, respectively. The high-rate settler presented an impressive efficiency removing suspended solids (rates up to 98%). The research showed that the new \"Anaerobic Activated Sludge Blanket\" system (A2SB) can provide satisfactory performance even operating without the three-phase separator and influent distribution system. / O reator UASB, desenvolvido pelo Prof. Gatze Lettinga e colaboradores na Holanda há mais de trinta anos, é utilizado com sucesso em muitas estações de tratamento de esgoto sanitário em países de clima tropical e subtropical. Entretanto, ainda são relatadas sérias questões operacionais relacionadas aos separadores trifásicos e aspectos problemáticos envolvendo a complexidade de seu sistema de distribuição do esgoto afluente. O foco da presente pesquisa foi o de simplificar a distribuição e dispersão do esgoto no reator, assim como aprimorar a retenção de lodo, mediante substituição do sistema convencional de tubos por misturador mecânico e do (tradicional) separador trifásico por decantador de alta taxa, respectivamente. Em essência, propôs-se reator dividido em duas regiões distintas: uma para reação (i.e. digestão anaeróbia da matéria orgânica), na qual a manta de lodo foi agitada mecanicamente através do movimento rotacional de um impelidor, e outra, para remoção de sólidos suspensos mediante uso de decantador com placas paralelas; um sistema de recirculação do lodo também foi implantado, para bombear a biomassa sedimentada até o compartimento de digestão. A pesquisa foi subdividida em três fases: nas duas primeiras, experimentos em escala de bancada foram realizados visando obtenção de dados básicos para dimensionamento dos sistemas de agitação e de decantação, enquanto que a terceira fase consistiu na aplicação dessas tecnologias em sistema de tratamento, em escala piloto, com volume útil total de 20,8 m3 (composto por uma câmara de digestão de 17,0 m3 e um compartimento de 3,8 m3 para remoção de sólidos), assim como na análise de seu desempenho. Durante a pesquisa, esgoto sanitário foi utilizado para alimentar o sistema experimental, instalado na Escola de Engenharia de São Carlos. Ao longo do período de operação, que durou 130 dias, quatro condições operacionais foram testadas (caracterizadas pela agitação intermitente e diferentes taxas de carregamento hidráulico, que variaram entre 27,6 e 66,5 m3.d-1) e o sistema alcançou eficiências de remoção máxima para DBO, DQO e SST de 82%, 72% e 83%, respectivamente. O decantador de alta taxa apresentou surpreendente eficiência de remoção de sólidos suspensos (taxas de até 98%). A pesquisa demonstrou que o novo sistema A2SB (Anaerobic Activated Sludge Blanket) pode apresentar desempenhos satisfatórios, mesmo operando sem separador trifásico e sistema de distribuição do esgoto afluente.
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Flotação de alta taxa aplicada ao pós-tratamento de efluentes de reatores anaeróbios / High rate dissolved air flotation applying in the pos-treatment of anaerobics reactors effluentsCarvalho, Marcelo Eustáquio de 06 June 2003 (has links)
No presente trabalho foi utilizado um sistema de tratamento seqüencial de esgoto sanitário constituído de um reator anaeróbio de leito expandido (Ralex), com vazão de 10 m3/h, seguido de unidade piloto de flotação por ar dissolvido de alta taxa (FADAT) contendo placas paralelas em seu interior, com vazão de 5,58 m3/h. Para tempo de floculação de 20 min, foram estudados, como coagulantes, dosagens de cloreto férrico de 50 mg/L e 70 mg/L, taxas de aplicação superficial de 21 m/h e 42 m/h, gradiente médio de velocidade de floculação de 60 s-1, 80 s-1 e 100 s-1 e frações de recirculação de 8%, 13% e 18%. Dentre o conjunto de condições operacionais da unidade piloto FADAT estudada, foi considerado o mais vantajoso: taxa de aplicação superficial no flotador de 21 m/h, dosagem de cloreto férrico de 70 mg/L, gradiente médio de velocidade de floculação de 80 s-1 e 8,1 g de ar/m3 de efluente. Nessas condições foram obtidas as seguintes remoções: 84% de turbidez (residual entre 6,3 e 62 uT), 73% de DQO (residual entre 20 e 156 mgO2/L), 75% de fósforo (residual entre 0,5 e 1,9 mgP/L) e 67% de SST (residual entre 8 e 80 mg/L de SST). Os resultados demonstraram que o emprego da unidade FADAT como pós-tratamento de efluente de reator anaeróbio proporciona economia de energia, tendo em vista requererem de 75 a 50% da quantidade de ar exigida pelos sistemas de flotação convencional. / In this wok a sewage sequential treatment consisting of an expanded bed anaerobic reactor (EBAR) with 10 m3/h flow was used, folowed by a high rate DAF containing parallel plates in its interior, with 58 m3/h. For a floculation time of 20 minutes, were studied chemical additives, ferric chlorode dosages of 50 mg/L and 70 mg/L, overflow rates of 21 m/h and 42 m/h, velocity gradients of 60 s-1, 80 s-1 e 100 s-1 and reciculation rate between 8%, 13% and 18%. Among the group of operational conditions of the pilot unit studied high rate DAF the most advantageous was considered: overflow rates of 21 m/h in the high rate DAF of 21 m/h, ferric chlorode dosages of 70 mg/L, velocity gradients of 60 s-1, and air requirements of 8,1 g of air/m3 of wastewater. In those conditions they were obtained the following removals: 84% of turbidez (residual between 6,3 and 62 UT), 73% of DQO (residual\' between 20 and 156 mgO2/L), 75% of phosphorus (residual between 0,5 and 1,9 mgP/L) and 67% of SST (residual between 8 and 80 mg/L of SST). The results demonstrated that the employment of the unit high rate DAF as post-treatment of the anaerobic eflluents provides economy of energy, tends in view they request of 75 to 50% of the amount of air demanded by the systems of conventional flotation.
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Performance Informed Technical Cost Modeling for Novel ManufacturingRobin Joseph Glebes (7443716) 17 October 2019 (has links)
<p>Inaccurate cost
estimates contribute to lost implementation opportunity of novel manufacturing
technologies or lost revenue due to under-bidding or loss of an over-bid
contract. High-volume, long-term orders, such as those the automotive industry
begets, are desired as they lock in revenue streams for months into years.
However, high-rate composite materials and their manufacturing processes are
novel among the industry and traditional costing methods have not advanced at a
proportional rate. This research effort developed a method to reduce the
complex composite manufacturing systems to fungible, upgradable, and linkable
individual processes that derive their manufacturing parameters from the
performance part design process. Employing technical cost modeling, this method
accurately quantifies the value of pursuing composite manufacturing by
integrating impregnation, solidification, heat transfer, kinetics, and
additional technical data from computer-aided part design simulation tools to
deliver an accurate cost estimate. </p>
<p>Cost modeling provides a
quantitative result that weighs heavily in the decision making process for adoption
of a new manufacturing method. In this dissertation, three case studies were
investigated for three different management decision cases: part production
management, in-house manufacturing management, and global manufacturing
management. </p>
<p>Part production management
is the decision making process for selecting a certain manufacturing method. A
case study with a Tier 1 Part Producer was conducted to provide a comparison of
two emerging novel preforming systems versus their in-use, metals based high-rate
manufacturing line in manufacturing a structural automotive part. Determining
material usage was the primary cost driver focus. Equipment Supplier A’s
process operated by seaming single layers of thermoplastic tape into rolls and
then stacking prior to consolidation and resulted in a scrap rate of 23-28%
with a cost of $32.87-36.01 per kilogram saved depending on the input tape
width. Equipment Supplier B’s layup process, essentially a multi-head automatic
tape layup machine, resulted in scrap rate of 20-27% with a cost of
$34.48-36.67 per kilogram saved depending on the input tape width. This
exceeded the Tier 1 Part Producer’s requirement of $6.6-11
per kilogram saved and led to them to abandon this
application as a feasible project and instead look for a different part with a
higher return regarding cost for weight saved.</p>
<p>In-house manufacturing
management is the decision making process governing manufacturing operating
procedures. A case study for the Manufacturing Design Laboratory’s (MDLab)
hybrid molding line was undertaken to determine the manufacturing cost for a
composite test coupon. Processing parameters were obtained from three sources:
performance design computer aided engineering (CAE), common industry transfer
estimation times, and a calculated preform layup time. Compared to a similarly shaped
test coupon made of aluminum, highly-automated manufacturing realizes weight
savings of 46.25% and cost savings of 16.5%. Low-automation manufacturing
captures the same weight savings, but has a cost for weight saved penalty, cost
increase, of $9.89 per kilogram, showing how influential the labor contribution
is to manufacturing cost. </p>
<p>Global manufacturing
management is the decision making process governing manufacturing location.
Various manufacturing cost drivers are location dependent, thus a dataset was
developed to alter these parameters for the U.S. states. Global comparisons are
accomplished through indexing of global cost of living allowances and labor
rates. Within the U.S., high-automation
manufacturing costs in the West Coast/Pacific are 20.1% greater compared to the
Midwest and similarly, low-automation costs are 21.2% greater. Globally,
high-automation manufacturing costs in North America are 52.1% greater compared
to Asia while low-automation costs are 116.5% greater. These variations
highlight why we see geographically clustered manufacturing centers within the
states and major manufacturing relocations due to cost sensitive and labor sensitive
production. </p>
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The criminal career profile : a measure of criminal careersMallillin, Abigail Zsa-Zsa Capati 30 November 2006
The term criminal career is used to describe the course or progress of criminal activity: its onset, duration, termination, severity, and change in severity. Such a term has important implications, given that significant criminal justice, social, and health policies such as crime control, parole, and correctional treatment and management are predicated on achieving the reduction of criminal careers of serious, repeat offenders. Despite its conceptual simplicity, however, criminal career is often treated as having no depth or scope, for example, merely as the number of crimes or length of prison sentence. These indices often give no or little consideration to criminal career parameters and tend to account for only a small portion of the construct of criminal careers. Ideally, a simple metric to measure the onset, duration, termination, severity, and change in severity of a pattern of criminal activities is needed to facilitate the description and measurement of criminal careers of offenders. <p>The Criminal Career Profile (CCP), which uses commonly available criminological information and requires minimal professional skills to execute, can be considered a simple and precise measure of criminal careers. The CCP is a chronological representation on a Cartesian plane of the time in years an offender has spent in prison (y-axis) plotted against the time in years spent out of prison (x-axis) of all incarcerations and time spent in the community. Given that the CCP is a step function, a regression line can be generated. Serious crimes are generally given longer sentences, and more time in than out of prison would generate a steeper regression line. Shallower regression lines result from less time in than out of prison. As such, the CCP regression line can be considered an indication of the seriousness of offending, and the slope or angle of the regression line can be considered a quantitative index of criminal career severity. Larger slopes or angles (used in this Program of Research) suggest more serious criminal careers. Conversely, smaller slopes or angles suggest less serous criminal careers. Taken altogether, the CCP can provide a quantitative measure of criminal careers: its onset (age at first conviction, which is plotted as the first point on a CCP graph), duration (total time in and out of prison since onset), severity (CCP slope/angle), change in severity (change in CCP slope/angle), and termination (end point or when the CCP slope or angle becomes smaller and closer to 0).<p>This Program of Research was done to assess the CCPs validity and utility in measuring offenders criminal career. More specifically, the investigation focused on the seriousness of criminal careers. A number of criteria were used to validate the CCP angles ability to measure criminal career severity. In Study 1, psychopaths and violent recidivists showed a significantly larger CCP angle than nonpsychopaths and violent nonrecidivists, respectively. Finer groupings based on risk (high, medium, and low), a number of risk measures (Psychopathy Checklist Revised, Violence Risk Scale, and Violence Risk Scale Sexual Offender Version), and different types of offenders (i.e. violent, nonviolent, sexual, Dangerous Offenders) were used in Study 2. Two consistent findings across different groups of offenders in Study 2 were CCP angles significantly varied as a function of risk group and correlated with risk ratings. The pattern of results was that larger CCP angles tended to be associated with worse risk groups. In Study 3, both treated offenders and treatment dropouts showed a reduction in CCP angles from pre- to post-treatment. A nonsignificant interaction of group by treatment, however, suggests that post-treatment changes could not be attributed to treatment. Finally, Study 4 showed that CCP angles change with age. Taken altogether, the results of the four studies provided converging evidence for the validity of the CCP as a measure of criminal careers and the CCP angle as a measure of criminal career severity.
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Implementation of a Software-Defined Radio Transceiver on High-Speed Digitizer/Generator SDR14Björklund, Daniel January 2012 (has links)
This thesis describes the specification, design and implementation of a software-defined radio system on a two-channel 14-bit digitizer/generator. The multi-stage interpolations and decimations which are required to operate two analog-to-digital converters at 800 megasamples per second (MSps) and two digital-to-analog converters at 1600 MSps from a 25 MSps software-side interface, were designed and implemented. Quadrature processing was used throughout the system, and a combination of fine-tunable low-rate mixers and coarse high-rate mixers were implemented to allow frequency translation across the entire first Nyquist band of the converters. Various reconstruction filter designs for the transmitter side were investigated and a cheap implementation was done through the use of programmable base-band filters and polynomial approximation.
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The criminal career profile : a measure of criminal careersMallillin, Abigail Zsa-Zsa Capati 30 November 2006 (has links)
The term criminal career is used to describe the course or progress of criminal activity: its onset, duration, termination, severity, and change in severity. Such a term has important implications, given that significant criminal justice, social, and health policies such as crime control, parole, and correctional treatment and management are predicated on achieving the reduction of criminal careers of serious, repeat offenders. Despite its conceptual simplicity, however, criminal career is often treated as having no depth or scope, for example, merely as the number of crimes or length of prison sentence. These indices often give no or little consideration to criminal career parameters and tend to account for only a small portion of the construct of criminal careers. Ideally, a simple metric to measure the onset, duration, termination, severity, and change in severity of a pattern of criminal activities is needed to facilitate the description and measurement of criminal careers of offenders. <p>The Criminal Career Profile (CCP), which uses commonly available criminological information and requires minimal professional skills to execute, can be considered a simple and precise measure of criminal careers. The CCP is a chronological representation on a Cartesian plane of the time in years an offender has spent in prison (y-axis) plotted against the time in years spent out of prison (x-axis) of all incarcerations and time spent in the community. Given that the CCP is a step function, a regression line can be generated. Serious crimes are generally given longer sentences, and more time in than out of prison would generate a steeper regression line. Shallower regression lines result from less time in than out of prison. As such, the CCP regression line can be considered an indication of the seriousness of offending, and the slope or angle of the regression line can be considered a quantitative index of criminal career severity. Larger slopes or angles (used in this Program of Research) suggest more serious criminal careers. Conversely, smaller slopes or angles suggest less serous criminal careers. Taken altogether, the CCP can provide a quantitative measure of criminal careers: its onset (age at first conviction, which is plotted as the first point on a CCP graph), duration (total time in and out of prison since onset), severity (CCP slope/angle), change in severity (change in CCP slope/angle), and termination (end point or when the CCP slope or angle becomes smaller and closer to 0).<p>This Program of Research was done to assess the CCPs validity and utility in measuring offenders criminal career. More specifically, the investigation focused on the seriousness of criminal careers. A number of criteria were used to validate the CCP angles ability to measure criminal career severity. In Study 1, psychopaths and violent recidivists showed a significantly larger CCP angle than nonpsychopaths and violent nonrecidivists, respectively. Finer groupings based on risk (high, medium, and low), a number of risk measures (Psychopathy Checklist Revised, Violence Risk Scale, and Violence Risk Scale Sexual Offender Version), and different types of offenders (i.e. violent, nonviolent, sexual, Dangerous Offenders) were used in Study 2. Two consistent findings across different groups of offenders in Study 2 were CCP angles significantly varied as a function of risk group and correlated with risk ratings. The pattern of results was that larger CCP angles tended to be associated with worse risk groups. In Study 3, both treated offenders and treatment dropouts showed a reduction in CCP angles from pre- to post-treatment. A nonsignificant interaction of group by treatment, however, suggests that post-treatment changes could not be attributed to treatment. Finally, Study 4 showed that CCP angles change with age. Taken altogether, the results of the four studies provided converging evidence for the validity of the CCP as a measure of criminal careers and the CCP angle as a measure of criminal career severity.
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