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No Brasil, o modelo implantado de esgotamento sanitário é centralizado, baseado em grandes redes de coleta de esgoto para transporte até as estações de tratamento. No entanto, o atendimento para que uma maior parcela da população possa ser atendida, modelos e sistemas descentralizados devemser adotados. Os wetlands construídos são amplamente citados como soluções sustentáveis, com apelo natural e de custo competitivo para o tratamento de águas residuárias de diversas fontes e são ainda apontados como uma tecnologia adequada e viável para a implantação de sistemas descentralizados de esgotamento sanitário. Nesse contexto, o presente estudo buscou a partir de um estudo de caso compreender o comportamento de um wetlands construídos híbridos em escala real no tratamento de esgoto sanitário, com operação registrada de 50 meses. O estudo buscou compreender os problemas operacionais ocorridos e os efeitos sobre as eficiências de remoção de carga orgânica, as possíveis correlações entre o tempo de operação, dos wetlands construídos na eficiência de remoção de carga orgânica além da influência da temperatura do ar e pluviometria. A eficiência de remoção média ao longo dos 50 meses para DBO520 e DQO foi de 82% e 72% respectivamente. Nenhuma correlação de grande representatividade foi encontrada, mas correlações negativas fracas foram observadas entre a eficiência de remoção de carga orgânica e a temperatura ambiente e entre a mesma eficiência e o tempo de operação / The wastewater collection and treatment model adopted in Brazil is centralized, based on great networks and treatment plants; however, the provision to a large part of the population requires that models and systems be decentralized. The constructed wetlands are often mentioned as sustainable solutions, for its natural appeal and competitive cost for treating wastewater from several sources; they are also pointed out as a viable and adequate technology for the implementation of decentralized sanitation systems. In this scenario, this study aims at applying a scientific analysis, based on a case study, of a system of hybrid constructed wetlands for treating domestic sewage, in full-scale, whose operation was registered for 50 months. This dissertation aims at describing, in detail, the project criteria and the constructive methodologies used by reporting the advantages and problems created by these criteria, besides analyzing the efficiency in the removal of organic load affected by the wastewater system, testing if there is any correlation between time of operation of the wetland system and its efficiency to remove organic load, and between the variations of temperature in the region where the system is operating and the efficiency, and, finally, between pluviometry in the region where the system is operating and the efficiency. In conclusion, the study compares the results obtained from data of other full-scale systems in different locations, in full-scale. The study found average removal efficiency throughout the 50 months for BOD5 and COD of 82% and 72%, respectively. No major correlation was found, but weak negative correlations were observed between the organic load removal efficiency and room temperature, and between efficiency and time of operation

The purpose of this research is to hydraulically characterize an engineered wetland in Albany, Oregon. The wetland receives treated wastewater from both Albany Millersburg Water Reclamation Facility (AMWRF) and ATI Wah Chang. AMWRF's water is municipal waste water. ATI Wah Chang's water comes from its nearby metal processing plant. The wetland is designed to remove thermal input as well as nitrogen species from both sources. ATI Wah Chang effluent has significant nitrate concentrations. A reliable model is needed to estimate the denitrification potential of the wetland. In order to construct a model, accurate hydraulic parameters such as residence time and flow rate are needed. In the first few days after ATI started flow, the aquatic conductivity level of the wetland increased significantly. Conductivity was used as a tracer to estimate residence times in the wetland as well as to measure the split ratios from different water sources in the wetland (ATI Wah Chang and AMWRF). A pilot test on conductivity and flow rate was carried out on a single pond. The pilot test was designed to accurately measure the influent and effluent from a single pond. Using this information, rates of infiltration as well as unintended flow paths could be identified. A third tracer test was performed using Rhodamine W.T. This test allowed for the determination of the residence time of each pond, the wetland as a whole, and identified stagnant zones within the ponds. To simulate the nitrogen transportation and transformation process, a numerical model was developed. The model's input parameters include reaction rate constants for nitrification and denitrification, volume of each pond, flow rate, flow path connections, and temperature. The model simulated the tracer test that was performed on the wetland to verify its accuracy. The model is also capable of predicting denitrification potential in both pilot scale and field scale. It is also temperature sensitive because temperatures vary significantly; for instance, in winter when the average temperature in Albany is <5��C, denitrification rates decrease significantly. Through this research, hydraulic characterization as well as current denitrification rates in the wetland were identified. Strategies for increasing the denitrification rate were also identified through this research. / Graduation date: 2012

Human production needs are met through the use of modern technology that is increasingly recognised as a threat to the planetary ecosystem and social sub-system. In light of this recognition, there is evidence that a planned transition towards more sustainable technological infrastructure is occurring across various production sectors. This change is often associated with re-orientating technology based on the concept of sustainable development and national-level strategies such as <i>ecological modernisation</i>, which prescribes phasing-out environmentally malignant conventional technology for cleaner post-industrial solutions. There is evidence, however, that a transition towards cleaner technological options is occurring at the local level. In southern Ontario, Canada ecological technology (<i>ecotechnology</i>) has been adopted in small-scale agricultural and educational facilities for the management of manure and domestic sewage. Ecotechnology is designed to meet human production requirements and to restore the environment through combining natural systems and engineered components to achieve cleaner production. Two types of ecotechnologies were investigated during this research: <i>constructed treatment wetlands</i> for the management of manure and <i>greenhouse-based biological technologies</i> for the management of domestic sewage. These options are novel and can be expected to encounter barriers resulting from a <i>selection environment</i> favouring pre-existing technological options that have previously become established. The overall objective of the research was <i>to identify key factors both driving and constraining the adoption and implementation of the ecotechnology</i> across four case studies. This objective was accomplished through employing a qualitative, collective case study approach. The case studies revealed the motivation behind the adoption of the ecotechnology arose from the environmental values of users and formed the basis for rejecting the conventional options because they were not viewed as capable of improving the environment. However, the ecotechnology also exceeded user's aesthetic and operational level expectations. Barriers to the implementation of ecotechnology were also identified. The investigation revealed the existence of a <i>perspective-gap</i> between the ecological engineering science and traditional engineering science, which constrained implementation of the ecotechnology. Skepticism was found to arise due to the unique performance parameters and <i>soft</i> operational characteristics of ecotechnology, which contrast the <i>hard</i> technological fixes that are familiar to traditional engineering science. This perspective-gap may account for the institutional inertia, which became clear after the 1996 provincial budget reductions decreased the level of support for research and environmental technology development programs in Ontario. These reductions also devolved authority for small-scale wastewater treatment to the municipal level where lack of technical expertise and reliance on standardised regulations has constrained the development of alternatives. Constructive technology assessment suggests that the development of technology must be guided in cooperative <i>social learning</i> processes capable of reflecting the needs and values of stakeholders in order to achieve beneficial social and technological change. Evidence from the case studies revealed that a significant amount of capacity was developed when stakeholders collaborated and legitimated the <i>social experiments</i> where the ecotechnology was applied. These experiments demonstrate the significance of creating settings where users, technology proponents and provincial and local approval agents can collaborate. Through collaboration, social learning can be facilitated during the development of alternative technological solutions that may be congruent with ecological modernisation and the re-orientation of technology towards options that are ecologically-oriented.

Human production needs are met through the use of modern technology that is increasingly recognised as a threat to the planetary ecosystem and social sub-system. In light of this recognition, there is evidence that a planned transition towards more sustainable technological infrastructure is occurring across various production sectors. This change is often associated with re-orientating technology based on the concept of sustainable development and national-level strategies such as <i>ecological modernisation</i>, which prescribes phasing-out environmentally malignant conventional technology for cleaner post-industrial solutions. There is evidence, however, that a transition towards cleaner technological options is occurring at the local level. In southern Ontario, Canada ecological technology (<i>ecotechnology</i>) has been adopted in small-scale agricultural and educational facilities for the management of manure and domestic sewage. Ecotechnology is designed to meet human production requirements and to restore the environment through combining natural systems and engineered components to achieve cleaner production. Two types of ecotechnologies were investigated during this research: <i>constructed treatment wetlands</i> for the management of manure and <i>greenhouse-based biological technologies</i> for the management of domestic sewage. These options are novel and can be expected to encounter barriers resulting from a <i>selection environment</i> favouring pre-existing technological options that have previously become established. The overall objective of the research was <i>to identify key factors both driving and constraining the adoption and implementation of the ecotechnology</i> across four case studies. This objective was accomplished through employing a qualitative, collective case study approach. The case studies revealed the motivation behind the adoption of the ecotechnology arose from the environmental values of users and formed the basis for rejecting the conventional options because they were not viewed as capable of improving the environment. However, the ecotechnology also exceeded user's aesthetic and operational level expectations. Barriers to the implementation of ecotechnology were also identified. The investigation revealed the existence of a <i>perspective-gap</i> between the ecological engineering science and traditional engineering science, which constrained implementation of the ecotechnology. Skepticism was found to arise due to the unique performance parameters and <i>soft</i> operational characteristics of ecotechnology, which contrast the <i>hard</i> technological fixes that are familiar to traditional engineering science. This perspective-gap may account for the institutional inertia, which became clear after the 1996 provincial budget reductions decreased the level of support for research and environmental technology development programs in Ontario. These reductions also devolved authority for small-scale wastewater treatment to the municipal level where lack of technical expertise and reliance on standardised regulations has constrained the development of alternatives. Constructive technology assessment suggests that the development of technology must be guided in cooperative <i>social learning</i> processes capable of reflecting the needs and values of stakeholders in order to achieve beneficial social and technological change. Evidence from the case studies revealed that a significant amount of capacity was developed when stakeholders collaborated and legitimated the <i>social experiments</i> where the ecotechnology was applied. These experiments demonstrate the significance of creating settings where users, technology proponents and provincial and local approval agents can collaborate. Through collaboration, social learning can be facilitated during the development of alternative technological solutions that may be congruent with ecological modernisation and the re-orientation of technology towards options that are ecologically-oriented.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The wastewater from the dairy cattle installations, when poorly managed, unleashes environmental impacts. Because of this, it requires the implementation of technological alternatives with a goal of maintaining environmental quality. Alternatively it is highlight the constructed wetlands, which are systems with low operational requirement designed for treatment of wastewater from various origins. The utilization of this technology, which aims to treat wastewater from the dairy cattle, has been intensified since 1998. Nevertheless, in Brazil there are few studies related to this type of wastewater. This study aims evaluating the applicability of constructed wetlands for the treatment of dairy cattle wastewater. In this study it was implanted two units of artificial wetlands post storage tank (area 116 m²), which receives effluent from a dairy production unit (daily production capacity of 140 liters milk). The constructed wetlands were operated in parallel and are characterized by a horizontal flow constructed wetlands - HFCW (surface area of 26.5 m²) and vertical flow constructed wetland (VFCW) (surface area of 14.3 m²). Both filters were excavated in the soil and water proofed, filled with coarse sand (d10 = 0.30 mm and d60 = 0.75 mm) as filter material and planted with macrophyte Typha domingensis Pers. The filters were fed under a hydraulic regime of 3.98 m³/week for HFCW and 4.5m³/week for VFCW. The treated effluent was infiltrated in the soil, through swales constructed in the experiment area. By physico-chemical and biological over 12 months was observed better performance related to the treated effluent in HFCW with average loading removal of 87% of COD, 81% BOD, 90% of SS , 80% TNK 80% NH4-N and 68% PO43-- P, respectively. To VFCW the obtained rates were 70% of COD, BOD of 52%, 70% of SS, 73% of TNK , 81% of NH4-N and 16% of PO43-- P, respectively. It was quantified an average evapotranspiration of 49% in HFCW, whereas the majors evapotranspiration rates occurred in months with higher temperature and in higher macrophytes foliar area. The greatest nutrient content found in the macrophytes occurred simultaneously with the highest growing velocities, which occurred in the beginning of plant development. The foliar tissue of HFCW was responsible for removal of 5.12% of the N load and 3.16% of the P load applied. In VFCW the macrophytes removed 0.88% of the applied N load and 0.30% of the applied P load. From the results obtained in this study recommends the use of constructed wetlands as an alternative technology to the treatment of wastewater originating from the dairy cattle facilities. / Os efluentes oriundos das instalações de bovinocultura leiteira, quando mal gerenciados podem promover impactos ambientais significativos, necessitando, portanto, da implantação de alternativas tecnológicas com vistas à manutenção da qualidade ambiental. Dentre elas destacam-se os filtros plantados com macrófitas FPM (wetlands construídos), os quais são sistemas com baixo requerimento operacional, projetados para atuar na depuração de efluentes de origens diversas. A utilização desta tecnologia voltada para o tratamento de efluentes produzidos em salas de ordenha de bovinocultura de leite vem sendo intensificadas desde 1998, contudo, no Brasil poucos são os estudos relacionados com este tipo de efluente. Este trabalho tem como objetivo geral avaliar a aplicabilidade de filtros plantados com macrófitas, empregados no tratamento do efluente de uma instalação de bovinocultura de leite. Implantou-se duas unidades FPM pós lagoa de armazenamento (área 116 m²), a qual recebe efluente proveniente de uma unidade produtiva leiteira (capacidade diária de produção de 140 litros de leite). Os FPM foram operados em paralelo e caracterizam-se, por um filtro plantado com macrófitas de fluxo horizontal FPMH (área superficial de 26,5 m²) e um filtro plantado com macrófitas de fluxo vertical FPMV (área superficial de 14,3 m²). Ambos os filtros foram escavados no solo, impermeabilizados, preenchidos com areia grossa (d10 =0,30 mm e d60 =0,75mm) como material filtrante e plantados com a macrófita Typha domingensis Pers. O FPMH operou sob um regime hidráulico de 3,98 m³/semana e o FPMV com 4,5m³/semana. O efluente tratado foi infiltrado no solo, através de valas de infiltração construídas no local. Por meio do monitoramento físico-químico e biológico ao longo de 12 meses, verificou-se maior desempenho de efluente tratado para o FPMH com eficiências médias de remoção em termos de carga de 87% de DQO, 81% de DBO, 90% de SS, 80% de NTK, 80% N-NH4 e 68% de P-PO43-, respectivamente. Para o FPMV as eficiências obtidas foram de 70% de DQO, 52% de DBO, 70% de SS, 73% de NTK, 81% de N-NH4 e 16% de P- PO43-, respectivamente. Foi quantificado uma evapotranspiração média de 49% para o FPMH, sendo que as maiores taxas de evapotranspiração ocorreram nos meses em que a temperatura e a área foliar das macrófitas foram maiores. Notou-se que os maiores teores de nutrientes no tecido foliar das macrófitas ocorreram simultaneamente com as maiores velocidades de crescimento das mesmas, que se deram no início do desenvolvimento das plantas. O tecido foliar das macrófitas do FPMH foi responsável por remover 5,12% da carga de N e 3,16% da carga de P aplicada no filtro, já no FPMV as macrófitas removeram 0,88% da carga aplicada de N e 0,30% da carga aplicada de P. A partir dos resultados obtidos nesse estudo recomenda-se a utilização dos FPM como uma alternativa tecnológica de tratamento de efluente liquido oriundo das instalações de bovinocultura de leite.

Citizen science offers a potentially powerful tool for the environmental scientist to access large data sets over increasingly greater time scales. Given the ease of which information can be reported or shared online and the increase in community interest there is an overwhelming amount of data available. But two major questions remain; is the data reliable and how is it best used? This study addresses the first question by testing the ability of such data from Artportalen, Sweden’s Species Gateway for reporting observations of birds (and other flora and fauna), to reflect patterns in the presence and absence of breeding records of Tufted Duck (Aythya fuligula) and Eurasian Teal (Annas crecca). This was done by undertaking wetland assessments in a set of constructed wetland sites from Artportalen in Halland, Southern Sweden, with breeding records of the target species. A literature review was also undertaken to explore the existing ecological knowledge of breeding habitat requirements for each species. Physical and biological characteristics from the wetlands visited were then qualitatively compared to the existing ecological knowledge for each species’ preferred breeding habitat. This method resulted in some support for the reliability of this particular Citizen Science data, in that it reflected Tufted Duck’s preference to breed in wetlands closer to the coast, that provided some form of cover or screening around the edges and which had a large proportion of their shoreline bordered by tall emergent vegetation. Conversely, it reflected Eurasian Teal’s preference for inland wetlands that were closer to relatively open natural freshwater bodies, where tall emergent vegetation wasn’t as abundant. How this and other Citizen Science data can be used in the design and management of constructed wetlands for conservation purposes in light of these results is then discussed.

O lixiviado, líquido complexo gerado nos aterros sanitários e depósitos de lixo a céu aberto, apresenta características de um poluidor em potencial, de difícil tratamento, devido a processos físico-químicos e de decomposição biológica dos resíduos sólidos no aterro sanitário, somado à infiltração de água de chuva. Formas de atenuar e tratar esse tipo de efluente vão desde tratamentos biológicos até técnicas avançadas de oxidação, sendo estes últimos de alto custo em sua infraestrutura, operação e manutenção. Uma alternativa adotada nos últimos tempos por muitas cidades de Brasil e o mundo inteiro é o tratamento combinado de lixiviado de aterro sanitário com esgoto sanitário, por ter vantagens custo-benefício viáveis. Na presente pesquisa foi avaliada a remoção de nutrientes, como nitrogênio e fósforo, em três sistemas de banhados construídos em escala piloto operados em paralelo (sistemas B1, B2, e B3), sendo cada um deles composto por duas unidades em série de fluxo vertical seguidos por duas unidades em série de fluxo horizontal de escoamento subsuperficial, plantados com macrófitas emergentes L. Peruviana e Typha sp., respectivamente, para tratar a combinação de 10 % de lixiviado de aterro sanitário estabilizado com 90 % de esgoto sanitário afluente à ETE Canoas, com tratamento prévio (B1: UASB+CBR e B2: UASB) e sem tratamento prévio (B3: esgoto bruto/lixiviado), com taxa de aplicação superficial de 400L/m2.dia e aplicação em bateladas com períodos de aproximadamente 15 minutos. O estudo foi desenvolvido na estação climática de inverno da região Sul do Brasil, no qual a remoção média de amônio (N-NH4+) foi maior que 95 % nos três banhados não sendo observada diferença significativa para p> 0,05, entre eles, enquanto que a remoção de nitrato (NO3-) foi provavelmente limitada pela baixa relação carbono/nitrogênio (C/N). O fósforo total (PT) apresentou remoções maiores que 45 % nos três sistemas sem diferença significativa, porém foi observada diferença significativa para a remoção de ortofosfato (P-PO4-) (p> 0,05) no banhado B3, quando este mostrou remoção negativa. A remoção de N e P pela absorção das plantas (L. Peruviana e Typha sp.) foi de aproximadamente 1 % e 2 % respectivamente, comparado com a remoção destes nutrientes na fase líquida. A precipitação e evapotranspiração não apresentaram influência na remoção de nutrientes. / The leachate, complex liquid generated in landfills and open dumps, has characteristics of a potential polluter, difficult to treat due to physical and chemical processes and biological decomposition of solid waste in landfills, added to rainwater infiltration. Ways to mitigate and treat this type of effluent range from biological treatments to advanced oxidation techniques, the latter being of high cost in its infrastructure, operation and maintenance. An alternative adopted recently by many cities of Brazil and the whole world is the combined treatment of landfill leachate with sanitary sewer, having advantages viable cost-effective. In the present study the removal of nutrients such as nitrogen and phosphorus were evaluated, in three pilot scale constructed wetlands systems, operated in parallel, (systems B1, B2 and B3) consisting each one of two vertical flow units in series followed by two horizontal flow units of subsurface flow, planted with emerging macrophytes L. peruviana and Typha sp., respectively, to treat the combination of 10% of stabilized landfill leachate with 90% of urban raw wastewater from ETE Canoas, with previous treatment (B1: UASB+CBR and B2: UASB) and untreated (B3: raw sewage / leachate), with superficial application rate of 400 L / m2.day, fed in batch periods of approximately 15 minutes. The study was conducted during the winter season in the southern region of Brazil, in which the average removal of ammonium (N-NH4+) was higher than 95 % in the three systems without significant difference among them (p> 0.001) and the removal of nitrate (NO3-) was probably limited by the low ratio carbon / nitrogen (C / N). The total phosphorus (PT) removal was greater than 45 % without significant difference among the three systems however a significant difference was observed for orthophosphate (P-PO4-) (p> 0.05) removal at B3 system, when it showed a negative removal. The nitrogen and phosphorous removal due to the absorption by the plants (L. peruviana and Typha sp.) was approximately 1 % and 2 % respectively, compared to the removal of the nutrients in the liquid phase. The precipitation and evapotranspiration did not caused influence upon the nutrients removal.

Constructed wetlands (CWs) are artificial systems used for wastewater treatment, whose objective is to reproduce, under controlled conditions, the treatment mechanisms that occur in natural environments, through the exploration and improve the processes that involve the vegetation, porous media and microbial assemblages. Horizontal subsurface flow constructed wetlands (HSSF-CWs) is characterized by flow in a horizontal direction, in a gravel or sand beds planted or unplanted with emergent macrophytes whose the inlet and outlet are horizontally opposed, which allows the wastewater flow through the rhizosphere and have contact with the biofilm formed in subsurface. Traditional studies about CWs focuses on the efficiency of contaminants removal look at systems as a "black-boxes" from empirical approaches and do not distinguish between the different active removals processes. The development of numerical models, in order to helping to identify and improve the role of each element acting in the treatment, whether the properties of the porous media, constructive geometry, flow characteristics, among others, appears as an alternative to reach a more detailed understanding of the internal processes involved in CWs. In general, numerical models consist of governing equations (derived from the mathematical combination of the water balance and Darcy's law), initial conditions (they refer to the distribution of the hydraulic head in the model domain) and boundaries conditions (define the hydraulic or physical boundaries that delimit the model domain). In the last decade, different 1D and 2D numerical models have been developed and applied for the simulation of subsurface flow CWs under conditions of saturated horizontal flow (CWM1-RETRASO and PHWAT), variably saturated vertical flow (FITOVERT and HYDRUS-CW2D) and vertical or horizontally saturated flow (HYDRUS-CWM1). However, few studies regarding the application of 3D numerical models for CWs simulation are reported in the scientific literature. In this study, the hydrodynamic simulation of the porous media in a horizontal subsurface flow constructed wetland was run through the application of a 3D numerical model. The flow patterns were simulated according to the project design and scenarios with changes in the porous media hydrodynamic (hydraulic conductivity) and in the positioning of the wastewater distribution mechanisms (distribution along the cross section with two pipes) in order to verify the influence of these factors in the flow pattern and also to indicate advantages and disadvantages that contribute to the design. The softwares MODFLOW and MODPATH, in the GMS family code, were used for to simulate the direction and flow velocity, hydraulic head and pathlines. The model proved to be a powerful tool to simulation, allowing observing the interdependence between the hydrodynamic parameters and the hydraulic characteristics in the porous media. The simulated scenarios showed the possibility of improving the flow patterns, mainly using two pipes to distribute the wastewater in a more homogeneous way along the cross section of the bed. The use of a porous media with lower hydraulic conductivity also showed improvement in flow characteristics evaluated. However, the general context of wastewater treatment facilities (pretreatment units and tributary loads) should be considered, since materials with low hydraulic conductivity are more susceptible to clogging. Proper design is crucial to improving the treatment conditions in the HSSF-CWs and also to avoid the occurrence of hydraulic problems and damage to the treatment, such as the clogging. / Wetlands construídos (WCs) são tecnologias empregadas para o tratamento de águas residuárias, cujo objetivo é reproduzir, sob condições controladas, os mecanismos de depuração que ocorrem em meios naturais, através da exploração e aperfeiçoamento dos processos que envolvem a vegetação, o substrato e os microrganismos. Wetlands construídos de escoamento subsuperficial de fluxo horizontal (WCFH) são caracterizados pelo fluxo em direção horizontal através de um leito de cascalho ou areia, vegetado ou não com macrófitas emergentes, cujas entrada e saída dos efluentes são horizontalmente opostas, o que permite que as águas residuárias fluam através da rizosfera e tenham contato com o biofilme formado em subsuperfície. Tradicionalmente, os estudos sobre WCs incidem apenas sobre a remoção das concentrações de contaminantes, considerando esses sistemas como “black-boxes” a partir de abordagens empíricas, sem fazer distinção entre os diferentes processos atuantes. O desenvolvimento de modelos numéricos, como forma de auxiliar a identificar e aperfeiçoar o papel de cada elemento atuante no tratamento, quer sejam as propriedades do meio poroso, a geometria construtiva, as características de fluxo, entre outros, surge como alternativa para o alcance de uma compreensão mais detalhada dos processos internos intervenientes nos WCs. De uma forma geral, os modelos numéricos são constituídos por equações governantes (derivada da combinação matemática da equação de balanço de água e da lei de Darcy), por condições iniciais (dizem respeito à distribuição da carga hidráulica no domínio do modelo) e por condições de contorno (definem as fronteiras hidráulicas ou físicas que delimitam o domínio do modelo). Na última década, diferentes modelos 1D e 2D foram desenvolvidos e aplicados para a simulação de WCs de escoamento subsuperficial em condições de fluxo horizontal saturado (CWM1-RETRASO e PHWAT), vertical variavelmente saturado (FITOVERT e HYDRUS-CW2D) e vertical ou horizontal variavelmente saturado (HYDRUS-CWM1). Porém, poucas experiências relativas à aplicação de modelos 3D para simulação de WCs são relatadas pela literatura científica. Neste trabalho, a simulação da hidrodinâmica do meio poroso de um sistema de tratamento de efluentes do tipo wetlands construídos de escoamento subsuperficial de fluxo horizontal foi realizada por meio da aplicação de um modelo numérico 3D. Foram simuladas as condições de fluxo conforme as especificações de um projeto de engenheria, e também cenários com mudanças nas características hidrodinâmicas do meio poroso (condutividade hidráulica) e no posicionamento dos mecanismos de distribuição das águas residuárias (distribuição ao longo da seção transversal por meio de duas tubulações) visando verificar a influência desses fatores no sistema de fluxo e também indicar vantagens e desvantagens que contribuam para a elaboração de projetos. Os softwares MODFLOW e MODPATH, executados por meio da interface GMS, foram utilizados para a simulação da direção e velocidade de fluxo, nível hidráulico e linhas de trajetória das partículas transportadas por advecção. O modelo provou ser uma ferramenta poderosa para a simulação, permitindo visualizar a interdependência entre os parâmetros hidrodinâmicos e as características hidráulicas do meio poroso. Os cenários simulados mostraram a possibilidade de melhoria dos padrões de fluxo, principalmente por meio do uso de duas tubulações para distribuição dos efluentes de forma mais homogênea ao longo da seção transversal do leito. O uso de materiais com menor condutividade hidráulica também apresentou melhoria nas características de fluxo avaliadas. Porém, deve-se considerar o contexto geral das instalações de tratamento das águas residuárias (unidades de tratamento preliminar e cargas afluentes), visto que materiais com baixa condutividade hidráulica são mais susceptíveis ao entupimento. A concepção adequada é crucial para melhorar as condições de tratamento verificadas nos WCFH e também para evitar a ocorrência de danos e problemas hidráulicos, como a estagnação de fluxo em zonas de baixa velocidade de escoamento.

Submitted by João Gabriel Thomaz Queluz null (queluz13@terra.com.br) on 2016-11-30T18:09:17Z No. of bitstreams: 1 Tese (João Queluz).pdf: 4075935 bytes, checksum: 5e22f8f089d2895be8857e7315e76c88 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-12-02T15:49:28Z (GMT) No. of bitstreams: 1 queluz_jgt_dr_bot.pdf: 4075935 bytes, checksum: 5e22f8f089d2895be8857e7315e76c88 (MD5) / Made available in DSpace on 2016-12-02T15:49:28Z (GMT). No. of bitstreams: 1 queluz_jgt_dr_bot.pdf: 4075935 bytes, checksum: 5e22f8f089d2895be8857e7315e76c88 (MD5) Previous issue date: 2016-11-08 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A maioria dos sistemas de tratamento de águas residuárias é complexa, têm construção e manutenção dispendiosas e necessitam de recursos humanos qualificados para operação, características que praticamente inviabilizam sua adoção na zona rural do país. Áreas rurais demandam sistemas de custo reduzido, simples e de fácil operacionalidade, características encontradas em sistemas de alagados construídos. Os objetivos do presente trabalho foram: desenvolver um sistema alagado construído para o tratamento de águas residuárias; avaliar a eficiência do alagado construído utilizando diferentes densidades de macrófitas; verificar a resposta do sistema a diferentes taxas de aplicação de matéria orgânica; e ajustar e modificar modelos hidráulicos que representem a cinética de remoção de matéria orgânica e de coliformes fecais. Foi desenvolvido um sistema de tratamento com três leitos de alagados construídos, compostos por quatro caixas d’água retangulares ligadas em série. As caixas d'água foram preenchidas com o material suporte (brita #0) até a altura de 30 cm e ficaram saturadas com efluente até a altura de 25 cm. Os alagados construídos foram cultivados com diferentes densidades (0, 11,5 e 23 plantas m-2) de taboa (Typha latifólia). Cada leito recebeu 50 litros diários de água residuária doméstica, resultando em 3,2 dias de tempo de detenção hidráulica nominal. A eficiência do sistema foi avaliada pela análise de coliformes fecais, coliformes totais, condutividade elétrica, demanda bioquímica de oxigênio, demanda química de oxigênio, fósforo total, nitrogênio total, pH, potássio, potencial redox, sólidos suspensos totais, temperatura e turbidez. Análise de regressão linear foi realizada para comparar a eficiência dos três alagados construídos na remoção de matéria orgânica e de patógenos. Além disso, os dados de demanda química de oxigênio e de coliformes fecais foram comparados com modelos hidráulicos convencionais (fluxo em pistão e tanques em série) com uso do coeficiente de determinação. Os alagados construídos foram eficientes na remoção de coliformes fecais (99%), demanda bioquímica de oxigênio (72%), demanda química de oxigênio (80%), nitrogênio total (73%), fósforo total (83%), potássio (54%) e sólidos suspensos totais (98%). A densidade de macrófitas não alterou a eficiência de remoção de coliformes fecais e de demanda química de oxigênio nos três alagados construídos. Porém, os alagados cultivados com macrófitas (11,5 e 23 plantas m-2) foram mais eficientes na remoção de nitrogênio, fósforo e potássio. O sistema alagado construído foi sensível às taxas de aplicação de matéria orgânica, havendo correlação linear positiva entre as taxas aplicada e removida de matéria orgânica. Os dados de demanda química de oxigênio e coliformes fecais foram comparados com as estimativas fornecidas pelos modelos hidráulicos de fluxo em pistão e de tanques em série. O modelo hidráulico de fluxo em pistão convencional foi, então, modificado incluindo-se um fator de resistência à degradação (q). O modelo hidráulico de fluxo em pistão modificado representa mais adequadamente a cinética de remoção de matéria orgânica do que os modelos hidráulicos convencionais de fluxo em pistão e de tanques em série. (q = 0,521631, quando a evapotranspiração é considerada e q = 0,479332 quando a evapotranspiração não é considerada). Por outro lado, o modelo modificado não é superior ao modelo convencional em relação à remoção de coliformes fecais. Concluindo, sugere-se que o modelo hidráulico modificado seja utilizado tanto para o dimensionamento quanto para a avaliação da eficiência de remoção de matéria orgânica em alagados construídos. / Most wastewater treatment systems are complex, have expensive cost for both construction and maintenance, and require skilled manpower for operation, features that practically precludes its adoption in rural areas of the country. Rural areas require simple and low-cost systems, characteristics found in constructed wetlands. This study aimed 1) to develop a constructed wetland system for wastewater treatment; 2) to assess the constructed wetlands efficiency using different densities of macrophytes; 3) to check the system response to different organic matter application rates; 4) to adjust and modify hydraulic models which represent the kinetics of organic matter and fecal coliforms removal. It was developed a treatment system with three constructed wetlands beds, composed by four rectangular water storage tanks connected in series. The water tanks were filled with gravel (Ø = 2.4 – 9.5 mm) to a height of 30 cm and were saturated with effluent to a height of 25 cm. The constructed wetlands were cultivated with different cattail (Typha latifolia) densities: 0, 11.5 and 23 plants m-2. Each bed received 50 liters of domestic wastewater per day, resulting in 3.2 days of nominal hydraulic retention time. The system efficiency was evaluated by the analysis of fecal coliforms, total coliforms, electrical conductivity, biochemical oxygen demand, chemical oxygen demand, total phosphorus, total nitrogen, pH, potassium, redox potential, total suspended solids, temperature, and turbidity. Linear regression analysis was performed to compare the efficiency of the three constructed wetlands in the removal of organic matter and pathogens. Furthermore, chemical oxygen demand and fecal coliforms data were compared with conventional hydraulic models using the coefficient of determination. The constructed wetlands were efficient for removing fecal coliforms (99%), biochemical oxygen demand (72%), chemical oxygen demand (80%), total nitrogen (73%), total phosphorus (83%), potassium (54%) and suspended solids (98%). The macrophytes density did not affect the efficiency of the three constructed wetlands for removing fecal coliforms and chemical oxygen demand. However, the beds cultivated with macrophytes presented higher efficiency in the removal of nitrogen, phosphorus and potassium. The constructed wetlands responded to the different organic matter application rates, with positive linear correlation between the applied and removed rates. The chemical oxygen demand and fecal coliforms data were compared with the predicted values provided by the conventional hydraulic models (plug flow and tanks in series). The conventional plug flow model was then modified and a degradation resistance factor (q) was included. The modified plug flow model showed better fit to the organic matter data than the conventional hydraulic models (whether or not evapotranspiration was considered: q = 0.521631 and q = 0.479332). On the other hand, the modified plug flow model did not show better fit to the fecal coliforms data than the conventional plug flow models. In conclusion, it is suggested that the modified plug flow hydraulic model should be used for the design and the assessment of organic matter removal efficiency in constructed wetlands. / FAPESP: 2014/05997-6