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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Tratamento de efluente textil pelo sistema de lodos ativados em batelada com adição de carvão ativado em po

Porto, Luiz Carlos da Silva, 1968- 19 February 2002 (has links)
Orientador: Ricardo de Lima Isaac / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil / Made available in DSpace on 2018-08-04T08:46:54Z (GMT). No. of bitstreams: 1 Porto_LuizCarlosdaSilva_M.pdf: 5854701 bytes, checksum: 8b8c1f5f9c94a0d763536c68fc82d3de (MD5) Previous issue date: 2002 / Resumo: O tratamento do efluente de indústrias têxteis é complexo, devido a sua variabilidade e à presença de substâncias tóxicas e lentamente biodegradáveis.Consequentemente, as regulamentações ambientais mais rigorosas e as pressões da sociedade e do mercado trazem um grande desafio às indústrias têxteis, principalmente às pequenas e médias. O objetivo deste trabalho foi avaliar o emprego do sistema de lodos ativados em batelada com adição de carvão ativado em pó (LAB/CAP), tema incipiente no Brasil, para o tratamento do efluente de uma indústria de beneficiamento têxtil, comparando-o com o sistema convencional (LAB). O efluente bruto estudado apresentou concentração média de carbono orgânico dissolvido (COD) de 177,21 :t 50,24 mg/L e valor médio de cor de 190 :t 94 unidades ADMI. Na Fase 1 realizaram-se ensaios de adsorção com o efluente industrial, a fim de escolher o melhor carvão ativado em pó (CAP) para o emprego no sistema biológico. Na Fase 2 foram operados seis reatores de quatro litros cada, com ciclos de 24 horas, um funcionando como controle e cinco com concentrações variando de 250 a 2.000 mg CAP/L. Na Fase 3 foram operados dois reatores, com três ciclos diários, um sem CAP e o outro com 1.000 mg CAP/L. Na Fase 4, adicionou-se CAP ao sistema LAB de uma indústria têxtil. Os resultados obtidos demonstraram que, em comparação com o sistema LAB, o sistema LAB/CAP apresentou maior eficiência de remoção de COD (diferença de até 6,56%) e de cor (diferença de até 46,63% no efluente tratado), maior nitrificação do efluente industrial (diferença de 43,14%), maior concentração de biomassa no reator (diferença de até 43,11 %) e maior estabilidade frente a variações de carga orgânica afluente. O custo de operação do sistema estudado, referente apenas à adição de CAP, foi de 0,03 US$/m3 tratado (valor de julho de 2001). O sistema LAB/CAP é, portanto, uma alternativa para aprimorar o tratamento biológico de efluentes têxteis, inclusive nas pequenas e médias empresas / Abstract: The treatment of textile wastewater is complex because it is highly variable and has xenobiotic compounds. Consequently, not only stringent environmental regulations but also society and market pressures result in an enormous challenge to textile industries, mainly small and middle-sized ones. The aim of this research was to investigate the use of sequencing batch reactor with addition of powdered activated carbon (SBR/P AC), which is an incipient subject in Brazil, to treatment of wastewater from a textile dyeing and finishing company, making a comparison with the conventional system (SBR). Raw industrial effluent had average DOC = 177,21 :t 50,24 mg/L and average color = 190 :t 94 ADMI units. At Phase 1 the best P AC for addition to biological system was found by adsorption tests. At Phase 2 six reactors with four liters each were operated with 24 hours of total cycle, one working as control and five working with concentration varying from 250 to 2.000 mg P AC/L. At Phase 3 two reactors were operated, at three cycle daily, one without PAC and another with 1.000 mg PAC/L. At Phase 4 PAC was additioned to the SBR plant of a textile mill. The results showed that, compared to the SBR, SBR/P AC presented higher DOC removal (difference up to 6,56%), higher color removal (difference up to 46,63% at treated wastewater), higher nitrification of waste water (difference of 43,14%), higher biomass concentration in reactor (difference up to 43,11 %) and higher stability to influent organic load variation. SBR/P AC operation cost , refered only to P AC addition, was 0,03 US$/m3 treated (as Ju1y 2001). Therefore, SBR/PAC is an alternative to improve biological treatment of textile wastewater, even in small and middle-sized companies / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
132

Aerobic sequencing batch reactor for the treatment of industrial wastewater from the brewery

Shabangu, Khaya Pearlman January 2017 (has links)
Submitted in fulfillment of the requirements for the degree of Master of Engineering, Department of Chemical Engineering, Durban University of Technology, Durban, KwaZulu-Natal, South Africa, 2017. . / One of the major effects of socio-economic change due to industrialisation is the generation of industrial wastewater, which requires treatment before being released into the environment. Laboratory-scale aerobic sequencing batch reactors under suspended-growth heterotrophic activated sludge were operated in different aeration configurations to study their effect on the treatment of wastewater generated by a local brewery. The main purpose of this study was to evaluate the performance of the two laboratory-scale aerobic sequencing batch reactors treating brewery wastewater under continuous low-oxygen dosing concentration and cyclic aeration schemes on SBR operation. The characterisation of brewery wastewater was undertaken to assess the physicochemical composition of the wastewater produced from one of the breweries in South Africa (SAB). The data showed distinctive characteristics of brewery wastewater, which coincided with studies previously carried out on characterisation of brewery wastewater. The COD average concentration of the brewery influent was 7100 mg/L, with average pH values of 7. The BOD and the total solids content of the brewery wastewater influent from the facility were both high, implying that the influent was very rich in organic content and its discharge into water-receiving bodies or the municipal treatment plant could have adverse effects. From these results, a need for a competitive treatment technology was clearly highlighted so as to carry out a feasible treatment of the influent for the brewery industry. The aerobic sequencing batch reactors were designed, fabricated and set up for laboratory-scale treatment of wastewater from the brewery for 15 weeks. The performance of the two SBR configurations was determined with reference to COD, BOD, TS, VS and TSS. The experimental results demonstrated that wastewater generated from the breweries can be treated successfully using both aeration configurations. The results obtained indicated that treatment efficiencies in terms of COD and BOD were 94 % and 85 % respectively, for the reactor operated under continuous aeration configuration, while 81 % and 65 % was achieved for the reactor operated in the cyclic aeration scheme. The findings from this study demonstrate that the performance of the reactor operated under the continuous aeration scheme was successful, and showed statistically significant differences from the performance of the reactor operated under cyclic aeration schemes. These findings imply that there is a potential for the equipment, including financial benefit as a result of operating aerobic sequencing batch reactors for treating brewery wastewater under continuous low-oxygen concentration dosing schemes. In this study, it was also established that the maximum COD removal could be reached at an optimum hydraulic retention times of 5 days for both reactors. This was based upon viewing the experimental data; it appeared that the most significant difference in percentage COD removal was for HRTs 3 days and 4 days. Although, due to less percentage COD removal observed from HRTs 5 days till 7 days, it was hence established that the optimum removal of high strength organics in the brewery wastewater could be achieved within 5 days of treatment time. The pH adapted at an average of 7 for all batch experimentations of the study. The temperature maintained an average of 23 oC ambient, throughout the experimental period. These physical parameters ensured that the microbial population was kept healthy, without inhibiting its biological degradation activity. Although, sludge build up was observed in both aerobic SBRs on completion of each batch operation due to solids retention and organic pollutants biodegradation from the brewery wastewater. It was perceived that frequently reseeding both aerobic SBRs, as an alternative to 28 days sludge retention time would enhance the recovery of biomass, thus improving the overall removal of TSS consequently minimising sludge bulking in both reactors. / M
133

Modelagem e simulação das correlações de scale-up para o processo de flotação por ar dissolvido (fad) utilizando análise dimensional

Vasconcelos, Robson de Souza 01 December 2015 (has links)
Made available in DSpace on 2017-06-01T18:20:46Z (GMT). No. of bitstreams: 1 robson_souza_vasconcelos.pdf: 2328772 bytes, checksum: 33965c207f7afa9baa550e0bb0bdff79 (MD5) Previous issue date: 2015-12-01 / The implantation costs of dissolved air flotation (DAF) pilot units require special strategies due to the lack of correlations between laboratory and industrial scale, as novel flotation methods have been considered strictly from an economic standpoint. In this sense, significant efforts have been made to describe and model a scale-up to the process of FAD, being necessary to design and validate a scale-up forecasting model to promote a change in the required scale. In this study a scale-up correlation for a pilot unit project was determined based on the analysis of dynamic similarity correlations involving the predominant phenomena of a dissolved air flotation (DAF) chamber used in separating and recovering oily water. With the aid of computational fluid dynamics and videos of microbubble and floc flow, inertia and gravity were identified as the predominant phenomena in a DAF chamber by the discrepancy between the average speeds of rise of microbubbles and flakes of 8.73 10-7 m/s and 1.17510-5 m/s, respectively. The simulations were performed using ANSYS software and measurements were made with the aid of a camera. The strategy described herein is simple and reduces the likelihood of future risks in scale-up investments. / Os custos com a implantação de unidades piloto de flotação por ar dissolvido (FAD) requerem estratégias especiais em função da falta de correlações entre a escala laboratorial e a industrial, uma vez que os projetos de FAD têm sido concebidos apenas sob o ponto de vista econômico. Nesse sentido, tem-se realizado esforços significativos para descrever e modelar um scale-up para o processo de FAD, sendo necessário elaborar e validar um modelo de previsão de scale-up para promover a mudança de escala necessária. No presente trabalho foi obtida uma correlação de scale-up como base para o projeto de uma unidade piloto, a partir de um modelo físico em escala de laboratório por meio da análise de correlações de semelhança dinâmica envolvendo grandezas predominantes em uma câmara de FAD usada na separação e recuperação de águas oleosas. Com auxílio da fluidodinâmica computacional e de vídeos dos fluxos de microbolhas e flocos, as forças de inércia e de gravidade foram identificadas como as grandezas predominantes em uma câmara de FAD pela discrepância entre as velocidades médias de ascensão de microbolhas e flocos, de 8,7310-7 m/s e 1,17510-5 m/s, respectivamente. As simulações foram realizadas por meio do software ANSYS e as medidas foram efetuadas com o auxílio de uma câmera fotográfica. A metodologia de trabalho empregada permitiu o desenvolvimento de uma técnica simples e de baixo custo, diminuindo a probabilidade de riscos futuros em um investimento de scale-up.
134

Effect of copper and nickel on the performance of an activated sludge system treating cellulose acetate wastewater

Sadagopan, Rishi S. 29 September 2009 (has links)
This research investigated the effect of copper and nickel on the performance of a laboratory scale activated sludge system. The wastewater used for this research was the influent to the activated sludge process at the Hoechst Celanese cellulose acetate manufacturing plant, located at Narrows, Virginia. The influent wastewater to the experimental unit was pretreated with lime and then selected amounts of copper and nickel were added separately or together to evaluate their effects on the performance of the system. The Specific Uptake of Metal (SUM), Dissolved Metal (DM), Total Metal Loading Rate (TMLR), and Specific Total Metal Loading Rate (STMLR) were useful parameters for analysis of the effects of the metals on activated sludge performance. No significant changes in effluent COD, SS, and OUR were observed for the acclimated activated sludge when the selected amounts of metals were added but not when either was added separately. The settling characteristics of the activated sludge deteriorated when a combination of copper and nickel were added. The SUM increased at a faster rate at higher metal loading rates than at lower metal loading rates to the reactor. The increases in dissolved metal concentrations in the mixed liquor were a linear function of the metal loading rates. / Master of Science
135

Evaluation of seasonal impacts on nitrifiers and nitrification performance of a full-scale activated sludge system

Awolusi, Oluyemi Olatunji January 2016 (has links)
Submitted in complete fulfillment for the degree of Doctor of Philosophy (Biotechnology), Durban University of Technology, Durban, South Africa, 2016. / Seasonal nitrification breakdown is a major problem in wastewater treatment plants which makes it difficult for the plant operators to meet discharge limits. The present study focused on understanding the seasonal impact of environmental and operational parameters on nitrifiers and nitrification, in a biological nutrient removal wastewater treatment works situated in the midlands of KwaZulu Natal. Composite sludge samples (from the aeration tank), influent and effluent water samples were collected twice a month for 237 days. A combination of fluorescent in-situ hybridization, polymerase chain reaction (PCR)-clone library, quantitative polymerase chain reaction (qPCR) were employed for characterizing and quantifying the dominant nitrifiers in the plant. In order to have more insight into the activated sludge community structure, pyrosequencing was used in profiling the amoA locus of ammonia oxidizing bacteria (AOB) community whilst Illumina sequencing was used in characterising the plant’s total bacterial community. The nonlinear effect of operating parameters and environmental conditions on nitrification was also investigated using an adaptive neuro-fuzzy inference system (ANFIS), Pearson’s correlation coefficient and quadratic models. The plant operated with higher MLSS of 6157±783 mg/L during the first phase (winter) whilst it was 4728±1282 mg/L in summer. The temperature recorded in the aeration tanks ranged from 14.2oC to 25.1oC during the period. The average ammonia removal during winter was 60.0±18% whereas it was 83±13% during summer and this was found to correlate with temperature (r = 0.7671; P = 0.0008). A significant correlation was also found between the AOB (amoA gene) copy numbers and temperature in the reactors (α= 0.05; P=0.05), with the lowest AOB abundance recorded during winter. Sanger sequencing analysis indicated that the dominant nitrifiers were Nitrosomonas spp. Nitrobacter spp. and Nitrospira spp. Pyrosequencing revealed significant differences in the AOB population which was 6 times higher during summer compared to winter. The AOB sequences related to uncultured bacterium and uncultured AOB also showed an increase of 133% and 360% respectively when the season changed from winter to summer. This study suggests that vast population of novel, ecologically significant AOB species, which remain unexploited, still inhabit the complex activated sludge communities. Based on ANFIS model, AOB increased during summer season, when temperature was 1.4-fold higher than winter (r 0.517, p 0.048), and HRT decreased by 31% as a result of rainfall (r - 0.741, p 0.002). Food: microorganism ratio (F/M) and HRT formed the optimal combination of two inputs affecting the plant’s specific nitrification (qN), and their quadratic equation showed r2-value of 0.50. This study has significantly contributed towards understanding the complex relationship between the microbial population dynamics, wastewater composition and nitrification performance in a full-scale treatment plant situated in the subtropical region. This is the first study applying ANFIS technique to describe the nitrification performance at a full-scale WWTP, subjected to dynamic operational parameters. The study also demonstrated the successful application of ANFIS for determining and ranking the impact of various operating parameters on plant’s nitrification performance, which could not be achieved by the conventional spearman correlation due to the non-linearity of the interactions during wastewater treatment. Moreover, this study also represents the first-time amoA gene targeted pyrosequencing of AOB in a full-scale activated sludge is being done. / D
136

Comparison between granular and conventional activated sludge for trace metal elements sorption/desorption. Case of copper for landspreading application in France and in Vietnam / Comparaison entre des boues d’épuration issues de systèmes conventionnels ou granulaires pour l’adsorption des métaux et l’application au cuivre lors de l’épandage des boues sur des sols Français et Vietnamien

Vu, Cam Tu 15 March 2017 (has links)
L'épandage des boues d'épuration est un mode de valorisation à la fois écologique et économique pour autant que l'on maitrise leur qualité et notamment la concentration des métaux lourds mobilisables. Le cuivre est une molécule très répandue, naturelle dans l'environnement, largement utilisée dans l'industrie et l'agriculture. En conséquence, les quantités de cuivre dans l'environnement ont augmenté, de sorte que ce dernier a été choisi dans cette étude comme représentant de la pollution anthropique pour évaluer sa mobilité en fonction de la qualité des boues épandues et des sols. 9 boues classiques et 2 sols (Sol d’herbe (de France) et sol de riz (du Vietnam)) ont été étudiés ainsi que des boues granulaires. Une méthodologie est proposée pour évaluer l'effet de la boue et de l'origine du sol sur la capacité de lessivage du cuivre lors de l'épandage des boues pour les activités agricoles. Les essais de désorption dans les colonnes de sol amendé par des boues ont montré que: a) quelle que soit l'origine du sol amendé, les boues de lit de roseaux (LR), séchées (BCD), centrifugées (BC) ont présenté une libération de Cu inférieure à 2% tandis que les boues de filtre-presse (BFP), digérées (BD), épaissies (BE) et calcaires (BCh) ont amélioré la disponibilité de Cu dans le sol; b) La lixiviation du cuivre dans le sol d’herbe (du France) amendé par des boues granulaires était supérieure à celle mesurée pour les échantillons classiquesde boues; c) Dans le sol de riz (de Vietnam), l'épandage des boues granulaires a limité la désorption de cuivre par rapport aux échantillons de boue (BCh), de filtre-presse (BFP), digérée (BD) ou centrifugée (BC). Quatre mécanismes sont proposés pour expliquer le devenir du Cu dans les sols: 1) le contrôle; 2) le groupe de Cp1, Cp2, BC, LR and BCD; 3) le groupe de BCh, BD, BE, BFP et 4) le groupe de boue granulaire. Il est constaté que pour le sol de riz contenant une faible teneur en matière organique, l'application de boues granulaires ou d'autres types de boue tels que les boues compostées ou séchées peut non seulement augmenter la teneur en éléments nutritifs, mais aussi réduire la capacité de lixiviation du cuivre. / The spreading of sewage sludge is both ecological and economical in sofar as their quality is controlled and in particular the low level of the heavy metals available. Copper is a very common substance, naturally occurring in the environment, widely used in industry and agriculture. As a result, quantities of copper in the environment have increased, so it has been selected in this study as representing human-induced pollution to assess its mobility in relation to the quality of sludge and soil. 9 different sludges and 2 soils (grass soil from France and paddy soil from Vietnam) were studied as well as granular sludge. A methodology was developed to evaluate the effect of sludge and soil origin on copper leaching ability during sludge application for agricultural activities. Desorption tests in soil-amended sludge columns showed that: a) Whateverthe origin of soil, the centri-dried (BCD), centrifuged (BC), reed-bed (LR) sludges presented a Cu release lower than 2% while filter-pressed (BFP), digested (BD), thickened (BE) and limed (BCh) sludge amended soils increased Cu availability in soil; b) the copper leaching of granular sludge amended grass soil was higher than those measured for conventional sludge samples; c) in paddy soil, landspreading of granular sludge limited the Cu desorption compared to limed (BCh), filter-press (BFP), digested (BD) and centrifuged (BC) sludge samples. Four mechanisms groups are proposed to explain the fate of Cu in soils: 1) the control; 2) the group of Cp1, Cp2, BC, LR and BCD; 3) the group of BCh BD BE and BFP, and 4) the group of granular sludge. It is found that paddy soil containing low organic matter, application of granular sludge orother types such as composted or dried sludge can not only increase the nutrient content but also reduce the leaching capacity of copper.
137

The Effect of Physicochemical Properties of Secondary Treated Wastewater Flocs on UV Disinfection

Azimi, Yaldah 05 March 2014 (has links)
The microbial aggregates (flocs) formed during secondary biological treatment of wastewater shield microbes from exposure to ultraviolet (UV) light, and decrease the efficiency of disinfection, causing the tailing phenomena. This thesis investigates whether the formation of compact cores within flocs induces higher levels of UV resistance. Moreover, it investigates the effect of secondary treatment conditions on the physicochemical properties of flocs’, effluent quality, and UV disinfection performance. Compact cores were isolated from the flocs using hydrodynamic shearing. The UV dose response curves (DRC) were constructed for flocs and cores, and the 53-63 μm cores showed 0.5 log less disinfectability, compared to flocs of similar size. Based on a structural model developed for the UV disinfection of flocs, floc disinfection kinetics was sensitive to the core’s relative volume, their density, and viability. The UV disinfection and floc properties of a conventional activated sludge (CAS) system, and a biological nutrient removal (BNR-UCT) system, including both biological nitrogen and phosphorus removal, was compared. The 32-53 μm flocs and the final effluent from the BNR-UCT reactor showed 0.5 log and 1 log improvement in UV disinfectability, respectively, compared to those from the CAS reactor. The BNR-UCT flocs were more irregular in structure, and accumulated polyphosphates through enhanced biological phosphorus removal. Polyphosphates were found to be capable of producing hydroxyl radicals under UV irradiation, causing the photoreactive disinfection of microorganisms embedded within the BNR-UCT flocs, accelerating their UV disinfection. Comparing the UV disinfection performance and floc properties at various operating conditions showed that increasing the operating temperature from 12 ºC to 22 ºC, improved the UV disinfection of effluent by 0.5 log. P-Starved condition, i.e. COD:N:P of 100:10:0.03, decreased the average floc size and sphericity, both by 50%. Despite the higher effluent turbidity of the P-Starved reactor, the final effluent’s UV disinfection improved by at least 1 log compared to the P-Normal and P-Limited conditions. The improvement in the floc and effluent disinfectability were accompanied by a decrease in floc sphericity and a decrease in the number of larger flocs in the effluent, respectively.
138

The Effect of Physicochemical Properties of Secondary Treated Wastewater Flocs on UV Disinfection

Azimi, Yaldah 05 March 2014 (has links)
The microbial aggregates (flocs) formed during secondary biological treatment of wastewater shield microbes from exposure to ultraviolet (UV) light, and decrease the efficiency of disinfection, causing the tailing phenomena. This thesis investigates whether the formation of compact cores within flocs induces higher levels of UV resistance. Moreover, it investigates the effect of secondary treatment conditions on the physicochemical properties of flocs’, effluent quality, and UV disinfection performance. Compact cores were isolated from the flocs using hydrodynamic shearing. The UV dose response curves (DRC) were constructed for flocs and cores, and the 53-63 μm cores showed 0.5 log less disinfectability, compared to flocs of similar size. Based on a structural model developed for the UV disinfection of flocs, floc disinfection kinetics was sensitive to the core’s relative volume, their density, and viability. The UV disinfection and floc properties of a conventional activated sludge (CAS) system, and a biological nutrient removal (BNR-UCT) system, including both biological nitrogen and phosphorus removal, was compared. The 32-53 μm flocs and the final effluent from the BNR-UCT reactor showed 0.5 log and 1 log improvement in UV disinfectability, respectively, compared to those from the CAS reactor. The BNR-UCT flocs were more irregular in structure, and accumulated polyphosphates through enhanced biological phosphorus removal. Polyphosphates were found to be capable of producing hydroxyl radicals under UV irradiation, causing the photoreactive disinfection of microorganisms embedded within the BNR-UCT flocs, accelerating their UV disinfection. Comparing the UV disinfection performance and floc properties at various operating conditions showed that increasing the operating temperature from 12 ºC to 22 ºC, improved the UV disinfection of effluent by 0.5 log. P-Starved condition, i.e. COD:N:P of 100:10:0.03, decreased the average floc size and sphericity, both by 50%. Despite the higher effluent turbidity of the P-Starved reactor, the final effluent’s UV disinfection improved by at least 1 log compared to the P-Normal and P-Limited conditions. The improvement in the floc and effluent disinfectability were accompanied by a decrease in floc sphericity and a decrease in the number of larger flocs in the effluent, respectively.
139

In situ microscopy for analysis of filamentous bacteria: optics end image evalaution / Microscopia in situ para análise de Bactérias filamentosas: ótica e processamento de imagens

Dias, Philipe Ambrozio 29 February 2016 (has links)
CAPES; CNPq / In the activated sludge process, problems of foaming and filamentous bulking can occur due to overgrowth of certain filamentous bacteria. Nowadays, these microorganisms are typically monitored by means of light microscopy combined with staining techniques. As drawbacks, these methods are susceptible to human errors, subjectivity and limited by the use of discontinuous microscopy. The present project aims the application of an in situ microscope (ISM) for continuous monitoring of filamentous bacteria, providing real-time examination, automated analysis and elimination of sampling, preparation and transport of samples. The ISM previously developed at the Hochschule Mannheim required adaptations for use within wastewater environment, specially in terms of impermeability and development of a cleaning mechanism. With a new objective lens design, the system was simplified to a single tubus and an externally activated cleaning system based on magnetism was created. A proper image processing algorithm was designed for automated recognition and measurement of filamentous objects, allowing real-time evaluation of images without any staining, phase-contrast or dilution techniques. Three main operations are performed: preprocessing and binarization; recognition of filaments using distance-maps and shape descriptors; measurement and display of total extended filament length. A 3D-printed prototype was used for experiments with respect to the new ISM’s design, providing images with resolution very close to the ones acquired with the previous microscope. The designed cleaning system has shown to be effective, removing dirt settled above the lens during tests. For evaluation of the image processing algorithm, samples from an industrial activated sludge plant were collected weekly for a period of twelve months and imaged without any prior conditioning, replicating real environment conditions. Experiments have shown that the developed algorithm correctly identifies trends of filament growth rate, which is the most important parameter for decision making. For reference images whose filaments were marked by specialists, the algorithm correctly recognized 72% of the filaments pixels, with a false positive rate of at most 14%. An average execution time of 0.7 second per image was achieved, demonstrating the algorithm suitability for real-time monitoring. / Em processos de lodo ativado, problemas de foaming e filamentous bulking podem ocorrer devido ao crescimento exagerado de bactérias filamentosas. Atualmente, o monitoramento de tais micro-organismos é feito por meio de métodos baseados em microscopia ótica combinada com técnicas de marcadores, os quais apresentam limitações intrínsecas da microscopia descontínua, são subjetivos e suscetíveis a erro humano. O presente projeto visa a aplicação de um microscópio in situ (ISM) para monitoramento contínuo de bactérias filamentosas, de forma a possibilitar análise instantânea, computadorizada, sem necessidades de recolher, preparar e transportar amostras. O ISM previamente desenvolvido na Hochschule Mannheim teve que ser adaptado para análise de águas residuais, especialmente em termos de impermeabilidade e a criação de um mecanismo de limpeza. Com a utilização de uma nova objetiva, o novo ISM foi simplificado para um tubo único e um sistema de limpeza ativado externamente baseado em magnetismo foi criado. Um algoritmo de processamento de imagens foi elaborado para reconhecimento e medição de comprimento de estruturas filamentosas, permitindo avaliação em tempo real de imagens sem qualquer técnica de marcadores, contraste de fase ou diluição. O mesmo consiste em três operações principais: pré-processamento e binarização; reconhecimento de filamentos por meio de mapeamento de dis- tâncias e descritores de forma; e, finalmente, medição e visualização do comprimento de cada filamento. Um protótipo construído via impressão 3D foi utilizado para avaliação o novo design do microscópio, fornecendo imagens com resolução bastante próxima das adquiridas com a versão anterior do sistema. O mecanismo de limpeza desenvolvido mostrou-se efetivo, capaz de remover partículas sedimentadas acima das lentes durante os testes. Para avaliação do algoritmo de processamento de imagens, amostras de uma planta industrial de lodo ativado foram coletadas semanalmente por um período de doze meses e imageadas sem qualquer condicionamento prévio, replicando condições reais de ambiente. Experimentos demonstraram que o algoritmo desenvolvido identifica corretamente tendências de aumento/decréscimo da concentração de filamentos, o que constitui o principal parâmetro para tomadas de decisão. Para imagens de referência cujos filamentos foram marcados por especialistas, o algoritmo reconheceu corretamente 80% dos pixels atribuídos a filamentos, com uma taxa de falso positivos de até 24%. Um tempo de execução médio de 0,7 segundo por imagem foi obtido, provando sua aptidão para formar uma ferramenta de monitoramento em tempo real.
140

Estudo de tratabilidade de efluentes de industria de catalisadores quimicos por lodos ativados por batelada (LAB) : Degussa, Americana, SP / Treatment study of effluents from chemical catalyst industry by activated sludge using sequencing batch reactor: Degussa, Americana, SP, Brrazil

Higa, Marcia Fernanda 23 February 2005 (has links)
Orientador: Carlos Gomes da Nave Mendes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-07T08:45:44Z (GMT). No. of bitstreams: 1 Higa_MarciaFernanda_M.pdf: 694032 bytes, checksum: 6aeb2dc109b978afe0fa9cd54037a168 (MD5) Previous issue date: 2005 / Resumo: O presente trabalho teve como objetivo principal a investigação do potencial de utilização de reatores de lodos ativados intermitentes para o tratamento conjunto de diversos tipos de águas residuárias geradas na indústria de catalisadores químicos Degussa, localizada no município de Americana - SP, incluindo-se os esgotos sanitários. Foram utilizados reatores de bancada e estudadas duas idades de lodo, simulando-se a aeração convencional e aeração prolongada. Foram investigados também quatro cenários possíveis, ou seja, quatro amostras compostas distintas de efluentes, de serem implantados em escala real. Os resultados obtidos mostraram que o sistema de aeração prolongada foi preferível em todas as situações estudadas, e que três dos cenários foram adequados ao tratamento biológico de lodos ativados por batelada, uma vez que apresentaram eficiências de redução dos valores de DQO superiores à 80%. No caso do tratamento conjunto de todas as águas residuárias da indústria, essa eficiência foi de 85,7 e 92,1% para as idades de lodo de 7 e 20 dias, respectivamente, indicando que o uso de reatores biológicos de lodos ativados por batelada constituiu-se em alternativa viável para a Degussa / Abstract: The present work had as main objective the investigation of the utilization potential of activated sludge sequencing batch reactors on the combined treatment of several kinds of wastewaters originated in the chemical catalyst industry Degussa, located in Americana - SP, including the domestic sewage. Workbench reactors were used and two sludge ages were studied, simulating the conventional and the prolonged aerations. Four possible sceneries, or four different effluent compound samples, possible of being full-scale introduced, were also investigated. The results showed that the system of prolonged aeration was preferable in alI the studied situations, and that three of the sceneries were suitable for the biological treatment by activated sludge using sequencing batch reactors, once they achieved efficiencies of reduction in the COD values greater than 80%. In the treatment inc1uding the total reunion of the industry effluents, this efficiency was 85,7 and 92,1%, to the sludge age of 7 and 20 days, respectively, indicating that the use of activated sludge sequencing batch biological reactors is a feasible alternative for Degussa / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil

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