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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.
71

Estudo comparativo da qualidade da água de chuva coletada em cobertura convencional e em telhado verde

Budel, Marcel Aramis 31 March 2014 (has links)
CAPES / O estudo consiste em uma comparação da qualidade da água da chuva coletada em duas formas distintas de captação: um sistema composto por um telhado inclinado com telhas de concreto, nomeada (casa 1) e o outro composto por uma cobertura plana com telhado verde, ou seja, vegetado, nomeada (casa 2). Tem por objetivo caracterizar os sistemas utilizados nas duas formas de cobertura, analisar a qualidade da água da chuva captada nos dois sistemas e fazer o acompanhamento da qualidade da água armazenada para posterior uso ao longo do estudo com o intuito de verificar a eficiência e comportamento dos sistemas de captação. Objetiva ainda encontrar relações nas variáveis envolvidas e apresentar os resultados de forma a estabelecer uma comparação qualitativa no desempenho das duas coberturas. O estudo foi realizado em duas casas localizadas na região noroeste da cidade de Curitiba, capital do Paraná. Na casa 1, com telhas de concreto, a água da chuva que escoa pelo telhado é primeiramente coletada por uma calha, seguindo por um duto vertical até o nível do solo, no qual se encontra um filtro simples, então a água é encaminhada para uma cisterna, onde é armazenada, para posterior uso na torneira externa para onde a água é bombeada. Já na casa 2, com cobertura plana vegetada, a água da chuva após passar pelo telhado verde é conduzida por dutos verticais até a cisterna de concreto no nível do solo, então uma eletrobomba recalca a água até um reservatório localizado na cobertura, acima do nível do telhado verde, para armazenamento e posterior uso na torneira externa. As amostras coletadas em nove eventos (17/05/2013 a 03/12/2013) foram analisadas quanto à: pH, turbidez, oxigênio dissolvido e temperatura, que foram medidos no próprio local. Demanda química de oxigênio (DQO), amônia, nitrito, nitrato e fosfato foram amostrados e analisados no laboratório de Saneamento da UTFPR, Campus Ecoville. Ainda quanto à presença de coliformes totais e termotolerantes (E. Coli), foram realizados em um laboratório terceirizado. Observou-se que o telhado convencional da casa 1 apresentou maior qualidade no parâmetro turbidez e demanda química de oxigênio (DQO), já o telhado verde diminuiu a acidez natural da água da chuva. As duas coberturas se mostraram eficientes pela concentração de amônia e nitrato, contudo indicaram concentrações elevadas de fosfato. Nos parâmetros microbiológicos os dois telhados não obtiveram qualidade suficiente para atender a NBR 15.527/2007. Desta forma, tomadas as devidas precauções, se recomenda o uso da água proveniente dos telhados, vegetados e convencional, para descargas de bacias sanitárias, irrigação de gramados e plantas ornamentais, lavagem de veículos, limpeza de calçadas e ruas, limpeza de pátios, espelhos d'água e usos industriais, conforme estabelecido na norma. / The study consists of a comparison of the quality of rainwater collected in two distinct ways of catchments: a system composed of a pitched roof with concrete tiles and another consisted of a vegetated flat coverage, as known as green roof. It aims to characterize the systems used in both forms of coverage, to analyze the quality of rainwater captured in the two systems and to monitor the quality of water stored for later use throughout the study in order to verify the efficiency and performance of catchment systems. It also aims to find relations in the involved variables and to present the results in order to establish a qualitative comparison in the performance of two coverages. The study was conducted in two houses located in the northwest region of the city of Curitiba, capital of Paraná. The appointee, house 1, has a pitched roof with concrete tiles, the rainwater that seeps through the roof is first collected by a trough, followed by a vertical duct to the ground level, with a simple filter, then the water is sent into a tank where it is stored for later use in the external faucet where the water is pumped. However, at house 2, with vegetated flat roof, after passing through the green roof the rainwater is driven by vertical ducts to the concrete tank at ground level, then an electric pump represses the water to a reservoir located on the roof, above the green roof ́s level for storage and later use on the external tap. Samples collected in nine events (17/05/2013 to 03/12/2013) were analyzed for pH, turbidity, dissolved oxygen and temperature, they were measured in situ. Chemical oxygen demand (COD), ammonia, nitrite, nitrate and phosphate were sampled and analyzed in the laboratory of Sanitation UTFPR Campus Ecoville. Nevertheless, for the presence of total and fecal coliforms (E. coli), tests were performed on an outsourced laboratory. As for the results obtained, the conventional roof house 1 rainwater had higher quality in turbidity and chemical oxygen demand (COD) parameter, whereas in house 2 the green roof reduced the natural acidity of rainwater. The two covers were effective in the concentration of ammonia and nitrate, though indicated high concentrations of phosphate. Microbiological parameters in neither roofs met the NBR 15.527/2007 quality. Thus, taken due precautions, it is recommend the use of water from roofs, vegetated and conventional, to flush toilets, to irrigate lawns and ornamental plants, to wash vehicles, to clean sidewalks and streets, to clean patios, water mirrors and to industrial uses, as defined in the standards.
72

Impacto do aproveitamento de água da chuva na drenagem: estudo de caso de um condomínio horizontal em Curitiba/PR / Impact of rainwater harvesting system in urban drainage: case study of a horizontal condominium in the city of Curitiba, Paraná

Teston, Andrea 30 March 2015 (has links)
CAPES / O ciclo hidrológico sustenta a falsa ideia de que a água é um recurso natural ilimitado e por esse motivo a questão foi negligenciada por muito tempo. Atualmente, entretanto, a preocupação com a água no planeta já ultrapassou os limites de países que sofrem de escassez. Isso resulta em uma busca constante por programas de conservação da água e pelo uso de fontes alternativas para consumo humano, dentre elas o aproveitamento de água da chuva. O presente trabalho tem por objetivo principal a verificação do impacto do aproveitamento de água da chuva em residências unifamiliares no consumo de água potável e na drenagem urbana. Através do estudo de caso de um condomínio horizontal na cidade de Curitiba, Paraná, fez-se uma avaliação quantitativa do volume de chuva aproveitado e extravasado no sistema de aproveitamento, através de do is métodos de dimensionamento do volume do reservatório: Método Prático Alemão (ABNT 15.527/2007) e Método do Decreto 293/2006 de Curitiba. Além disso, utilizando dados pluviométricos diários, desde 1997 até 2013, três cenários de demanda de água de chuva foram criados, dos quais é possível verificar a eficiência e a confiança dos sistemas adotados, a fim de determinar quanto da demanda é atendida e quanta água fica retida nos reservatórios. / The false idea that water is an unlimited natural resource is supported by the water cycle, and therefore the issue has been neglected for too long. Nowadays, however, the water problem on the planet has exceeded the boundaries of countries suffering from shortages. It results in a constant search for programs of water conservation and use of alternative sources for human consumption, including the use of rainwater. This paper presents, as the main objective, the verification of the impact of rainwater harvesting system in single family residences at consumption of drinking water and urban drainage. Through the case study of a horizontal condominium in the city of Curitiba, Paraná, it presents a quantitative assessment of the volume of rain that is used and overflowed, using two methods of sizing tank volume: Method Practical German (ABNT 15,527 / 2007) and Method of Decree 293/2006 of Curitiba. Furthermore, it uses daily rainfall data since 1997 until 2013 to creates three demand scenarios of rainwater. With it is possible to verify the efficiency and confidence of the adopted systems in order to determine how much of the demand is met and how much water is retained in reservoirs.
73

Impacto do aproveitamento de água da chuva na drenagem: estudo de caso de um condomínio horizontal em Curitiba/PR

Teston, Andrea 30 March 2015 (has links)
CAPES / O ciclo hidrológico sustenta a falsa ideia de que a água é um recurso natural ilimitado e por esse motivo a questão foi negligenciada por muito tempo. Atualmente, entretanto, a preocupação com a água no planeta já ultrapassou os limites de países que sofrem de escassez. Isso resulta em uma busca constante por programas de conservação da água e pelo uso de fontes alternativas para consumo humano, dentre elas o aproveitamento de água da chuva. O presente trabalho tem por objetivo principal a verificação do impacto do aproveitamento de água da chuva em residências unifamiliares no consumo de água potável e na drenagem urbana. Através do estudo de caso de um condomínio horizontal na cidade de Curitiba, Paraná, fez-se uma avaliação quantitativa do volume de chuva aproveitado e extravasado no sistema de aproveitamento, através de dois métodos de dimensionamento do volume do reservatório: Método Prático Alemão (ABNT 15.527/2007) e Método do Decreto 293/2006 de Curitiba. Além disso, utilizando dados pluviométricos diários, desde 1997 até 2013, três cenários de demanda de água de chuva foram criados, dos quais é possível verificar a eficiência e a confiança dos sistemas adotados, a fim de determinar quanto da demanda é atendida e quanta água fica retida nos reservatórios. / The false idea that water is an unlimited natural resource is supported by the water cycle, and therefore the issue has been neglected for too long. Nowadays, however, the water problem on the planet has exceeded the boundaries of countries suffering from shortages. It results in a constant search for programs of water conservation and use of alternative sources for human consumption, including the use of rainwater. This paper presents, as the main objective, the verification of the impact of rainwater harvesting system in single family residences at consumption of drinking water and urban drainage. Through the case study of a horizontal condominium in the city of Curitiba, Paraná, it presents a quantitative assessment of the volume of rain that is used and overflowed, using two methods of sizing tank volume: Method Practical German (ABNT 15,527 / 2007) and Method of Decree 293/2006 of Curitiba. Furthermore, it uses daily rainfall data since 1997 until 2013 to creates three demand scenarios of rainwater. With it is possible to verify the efficiency and confidence of the adopted systems in order to determine how much of the demand is met and how much water is retained in reservoirs.
74

Estudo comparativo da qualidade da água de chuva coletada em cobertura convencional e em telhado verde

Budel, Marcel Aramis 31 March 2014 (has links)
CAPES / O estudo consiste em uma comparação da qualidade da água da chuva coletada em duas formas distintas de captação: um sistema composto por um telhado inclinado com telhas de concreto, nomeada (casa 1) e o outro composto por uma cobertura plana com telhado verde, ou seja, vegetado, nomeada (casa 2). Tem por objetivo caracterizar os sistemas utilizados nas duas formas de cobertura, analisar a qualidade da água da chuva captada nos dois sistemas e fazer o acompanhamento da qualidade da água armazenada para posterior uso ao longo do estudo com o intuito de verificar a eficiência e comportamento dos sistemas de captação. Objetiva ainda encontrar relações nas variáveis envolvidas e apresentar os resultados de forma a estabelecer uma comparação qualitativa no desempenho das duas coberturas. O estudo foi realizado em duas casas localizadas na região noroeste da cidade de Curitiba, capital do Paraná. Na casa 1, com telhas de concreto, a água da chuva que escoa pelo telhado é primeiramente coletada por uma calha, seguindo por um duto vertical até o nível do solo, no qual se encontra um filtro simples, então a água é encaminhada para uma cisterna, onde é armazenada, para posterior uso na torneira externa para onde a água é bombeada. Já na casa 2, com cobertura plana vegetada, a água da chuva após passar pelo telhado verde é conduzida por dutos verticais até a cisterna de concreto no nível do solo, então uma eletrobomba recalca a água até um reservatório localizado na cobertura, acima do nível do telhado verde, para armazenamento e posterior uso na torneira externa. As amostras coletadas em nove eventos (17/05/2013 a 03/12/2013) foram analisadas quanto à: pH, turbidez, oxigênio dissolvido e temperatura, que foram medidos no próprio local. Demanda química de oxigênio (DQO), amônia, nitrito, nitrato e fosfato foram amostrados e analisados no laboratório de Saneamento da UTFPR, Campus Ecoville. Ainda quanto à presença de coliformes totais e termotolerantes (E. Coli), foram realizados em um laboratório terceirizado. Observou-se que o telhado convencional da casa 1 apresentou maior qualidade no parâmetro turbidez e demanda química de oxigênio (DQO), já o telhado verde diminuiu a acidez natural da água da chuva. As duas coberturas se mostraram eficientes pela concentração de amônia e nitrato, contudo indicaram concentrações elevadas de fosfato. Nos parâmetros microbiológicos os dois telhados não obtiveram qualidade suficiente para atender a NBR 15.527/2007. Desta forma, tomadas as devidas precauções, se recomenda o uso da água proveniente dos telhados, vegetados e convencional, para descargas de bacias sanitárias, irrigação de gramados e plantas ornamentais, lavagem de veículos, limpeza de calçadas e ruas, limpeza de pátios, espelhos d'água e usos industriais, conforme estabelecido na norma. / The study consists of a comparison of the quality of rainwater collected in two distinct ways of catchments: a system composed of a pitched roof with concrete tiles and another consisted of a vegetated flat coverage, as known as green roof. It aims to characterize the systems used in both forms of coverage, to analyze the quality of rainwater captured in the two systems and to monitor the quality of water stored for later use throughout the study in order to verify the efficiency and performance of catchment systems. It also aims to find relations in the involved variables and to present the results in order to establish a qualitative comparison in the performance of two coverages. The study was conducted in two houses located in the northwest region of the city of Curitiba, capital of Paraná. The appointee, house 1, has a pitched roof with concrete tiles, the rainwater that seeps through the roof is first collected by a trough, followed by a vertical duct to the ground level, with a simple filter, then the water is sent into a tank where it is stored for later use in the external faucet where the water is pumped. However, at house 2, with vegetated flat roof, after passing through the green roof the rainwater is driven by vertical ducts to the concrete tank at ground level, then an electric pump represses the water to a reservoir located on the roof, above the green roof ́s level for storage and later use on the external tap. Samples collected in nine events (17/05/2013 to 03/12/2013) were analyzed for pH, turbidity, dissolved oxygen and temperature, they were measured in situ. Chemical oxygen demand (COD), ammonia, nitrite, nitrate and phosphate were sampled and analyzed in the laboratory of Sanitation UTFPR Campus Ecoville. Nevertheless, for the presence of total and fecal coliforms (E. coli), tests were performed on an outsourced laboratory. As for the results obtained, the conventional roof house 1 rainwater had higher quality in turbidity and chemical oxygen demand (COD) parameter, whereas in house 2 the green roof reduced the natural acidity of rainwater. The two covers were effective in the concentration of ammonia and nitrate, though indicated high concentrations of phosphate. Microbiological parameters in neither roofs met the NBR 15.527/2007 quality. Thus, taken due precautions, it is recommend the use of water from roofs, vegetated and conventional, to flush toilets, to irrigate lawns and ornamental plants, to wash vehicles, to clean sidewalks and streets, to clean patios, water mirrors and to industrial uses, as defined in the standards.
75

Impact of in-field rainwater harvesting technology on household food security: a case of Guquka and Khayalethu villages in Central Eastern Cape Province

Hlanganise, Yoliswa Happiness January 2010 (has links)
The aim of this investigation was to assess the impact of the In-Field Rainwater Harvesting technology on household food security in the study area. The study was conducted in Nkonkobe Local Municipality of the Amathole District Municipality in central Eastern Cape Province. The areas under investigation are Guquka and Khayaletu villages of the Thyume Valley, which is located about 30 kilometres north of Alice. The method used to assess the impact of the IRWH on household food security was a pair wise comparison method. During September 2009, there were 60 (34 in Guquka and 26 in Khayaletu) households who adopted the technology in home gardens. In order to get a clear picture of the impact of the technology on food security, a decision was taken to assess both the project members and non-project members, hence the pairwise comparison method. The non-project members (also 60 households) were selected randomly from those who were interviewed during the situation analysis in 2004. Five indicators were used to assess household food security. These were household income, expenditure on food, diet diversity, energy-protein intakes, and micro-nutrient intakes (Vitamin A, C and Iron). The income and expenditure data were collected from the 120 households. However, the detailed food data were collected from selected cases from both groups at different times (seasons) of the year. A case study approach was employed in data collection. A total of 12 cases (six households per village) were selected for this investigation. These were selected mainly according to the degree of poverty. The total of six households from each village comprised three project members and three non-members i.e. one from each poverty class (non- poor, poor and ultra-poor) in both categories. The data on the kinds of food products consumed by households was gathered using the food account method (FAM). The food consumed was then analysed for nutrient adequacy. The main findings of this investigation show the IRWH technology to have a positive impact on food security and nutrition of the project members. The technology made significant contributions to the amount of energy and vitamins A and C consumed by households especially during wet seasons. Substantial contributions of garden produce were noted among the project members. However, these contributions were not enough to ensure household food security. The results indicate that there are nutritional problems in the study area. Firstly, there is protein- v energy malnutrition mainly affecting the poor and the ultra-poor households. Secondly, there is hidden hunger affecting all poverty categories, even the non-poor households. This is mainly demonstrated by poor diet quality i.e. diet that lacks essential nutrients identified
76

Developing community-informed technology for harvesting rainwater for domestic use in a semi-arid area of South Africa

Nyamukondiwa, Pertina 16 May 2020 (has links)
PhDRDV / Institute for Rural Development / Approximately, 780 million of people in the world lack access to safe water for domestic use. Out of these, 37 % are found in sub-Saharan Africa. Because of the negative impact of climate variability and change, scarcity of water is likely to continue worsening. Although semi-arid areas experience water shortages, they receive limited amounts of rainfall. Rainwater might help alleviate temporal water shortages. However, rainwater is rarely harvested for use when most needed. The PhD in Rural Development thesis research was carried out in Mabayeni village, which falls under Ward 35 of Collins Chabane Local Municipality in Limpopo Province of South Africa. It was designed to develop a grassroots community-informed prototype for a technology that could be used to harvest rainwater for domestic use. A series of interrelated studies with the following specific objectives underpinned the research: (1) To determine the extent of water scarcity; (2) To identify strategies households used to cope with inadequate availability of water for domestic use; (3) To document the rainwater harvesting techniques rural households used; (4) To compare the features of rainwater harvesting technology that people of different age groups preferred; (5) To develop community-preferred prototypes of rainwater harvesting technology with the best potential to increase access to water for domestic use; and (6) To evaluate the community-preferred prototypes of rainwater harvesting technology. Partly, the study was conducted as a follow-up to a Master’s research study on climate change carried out in 2014 in Mabayeni village. In the 2014 study, it was revealed that water scarcity was a major result of climate change in the area. In addition, Mabayeni was perceived as the driest compared to other villages in the ward. The Cresswell (2013) explanatory sequential mixed method design guided the study. Multi-stage sampling was followed to select respondents. This entailed categorizing respondents first dividing them by age and gender. Respondents were placed in the following clusters: children (boys and girls), youth (male and female), adult (men and women), and the elderly. This was done in order to ensure that there was triangulation of data sources. Various participatory research techniques were used to collect qualitative data for the same reason. For objective 1, data collection techniques such as photo voice, key informant interviews, focus group discussions, participatory mapping, transect walks, storytelling and seasonal diagramming were used. Data were analysed through card sorting, Atlas.ti version 7.5.7-mediated thematic content analysis, map ranking, matrix scoring and conversation analysis. Data collection techniques employed for objective 2 were similar to those used in objective 1 with the exception of participatory mapping. Thematic content analysis in Atlas.ti, map ranking and matrix ranking were used to analyse data for this objective. Only focus group discussions, key informant interviews and transect walks were used to collect data for objective 3. Data analysis techniques used were similar to those used in the previous objective with the exception of map ranking. For objective 4, data were collected through focus group discussions and analysed using matrix ranking and Atlas.ti-aided thematic content analysis. In objective 5, development of artefacts was guided by prototyping and sketch modelling techniques. Techniques such as verbal protocol analysis, mathematical calculations and presentation and analysis were used to analyse data. A questionnaire with open and closed ended questions was also used to collect data for the last objective. Open-ended questions were analysed using thematic content analysis. In addition, the Kruskal Wallis test in SPSS version 25 determined first, the two prototypes (one for zinc and another for thatch roof) that were regarded as the best; and second, if prototype component ratings significantly differed (p <0.05) across prototypes. As a post hoc test, the Dunn’s test in R Statistical Software version 3.3.0 was used for pairwise comparisons. Data saturation determined the sample size. A total of 17 community engagement sessions were held to collect, analyse and validate findings with the grassroots community members in Mabayeni village. Water scarcity in Mabayeni village was reconfirmed to be seasonal. The dry season in each year was five months long. During this time, residents adopted random, risky and unhygienic coping strategies. Although rainwater was collected from rooftops, there was no formal technology used to gather and store large quantities for later use. This was attributed to lack of resources and knowledge on how to develop such technologies. The most commonly preferred features of rainwater harvesting technology across interest groups related to water quality, construction materials and security. All interest groups preferred a technology that harvested clean/potable water. Moreover, the elderly wanted a technology that would help them access the stored water easily. In total, 14 prototypes were developed. When all the interest groups evaluated the prototypes, the ones that boys and men developed were selected as the best for zinc and thatched roofbased technologies, respectively. Selection of a prototype that children produced as the best underlined that children were an important resource that communities should never marginalise. Nor should their ability to contribute useful ideas be underestimated when seeking solutions to local challenges. Active involvement of grassroots community members in the entire design process helped tailor specifications of the technology to user needs, thereby highlighting the importance of inclusive decision making in development practice. This was also important because it created ownership and increased chances of adopting the technology. Lastly, the current study reaffirmed the view that postgraduate degree research can be harnessed to coproduce solutions to community-identified challenges. / NRF
77

Cellulose-Based Hydrogels for High-Performance Buildings and Atmospheric Water Harvesting

Noor Mohammad Mohammad (17548365) 04 December 2023 (has links)
<p dir="ltr">Smart windows, dynamically adjusting optical transmittance, face global adoption challenges due to climatic and economic variability. Aiming these issues, we synthesized a methyl cellulose (MC) salt system with high tunability for intrinsic optical transmittance (89.3%), which can be applied globally to various locations. Specifically, the MC window has superior heat shielding potential below transition temperatures while turning opaque at temperatures above the Lower Critical Solution Temperature (LCST), reducing the solar heat gain by 55%. Such optical tunability is attributable to the particle size change triggered by the temperature-induced reversible coil-to-globular transition. This leads to effective refractive index and scattering modulation, making them prospective solutions for light management systems, an application ahead of intelligent fenestration systems. MC-based windows demonstrated a 9°C temperature decrease compared to double-pane windows on sunny days and a 5°C increase during winters in field tests, while simulations predict an 11% energy savings.</p><p dir="ltr">Incorporating MC-based phase change materials in passive solar panels indicated optimized energy efficiency, offering a sustainable alternative. Real-time simulations validate practical applicability in large-scale solar panels. Furthermore, a temperature-responsive sorbent with a dark layer demonstrates an optimal optical and water uptake performance. Transitioning between radiative cooling and solar heating, the sorbent exhibits high water harvesting efficiency in lab and field tests. With an adjustable LCST at 38 ℃, the cellulose-based sorbent presents a potential solution for atmospheric water harvesting, combining optical switching and temperature responsiveness for sustainable water access. Furthermore, the ubiquitous availability of materials, low cost, and ease-of-manufacturing will provide technological equity and foster our ambition towards net-zero buildings and sustainable future.</p>
78

Análisis y caracterización de las instalaciones interiores de suministro de agua desde el punto de vista de ahorro

López Patiño, Gonzalo 07 March 2016 (has links)
[EN] SUMMARY It is a fact that in our environment there is a water shortage that affects the agricultural and urban freshwater consumption. The environmental conditions of climate change will aggravate the situation in the coming years. The efficient management of water resources is, and will be, an important issue for society that must be addressed from a social and technological point of view. Although nonfarm consumption represents only 30% of the total demand for freshwater, the urban water use is the more worrying because it directly affects the lives of people. A shortage of water resources is answered from two points of view. On the one hand, increasing supply through an increase in water uptakes, transfers from surplus basins, or desalination. On the other hand the reduction of demand, or efficient demand management. It is from this approach where this research takes place. The aim of the thesis is to develop a methodology to select the most appropriate water saving system to equip a building. The selection process arises from two approaches, each corresponding to a different use of the building. For buildings intended to develop a productive activity a cost-benefit selection method is used. For other buildings, a multicriteria selection method is used. For this last situation, application of analytic hierarchy process to selection of water saving systems is chosen. For the implementation of the multicriteria selection method, a series of selection criteria have to be defined and considered: water conservation, energy conservation, social and environmental impact, design, and economic viability. Each device or water saving system should be characterized on the basis of each of these criteria. In the thesis has been developed the way to characterize the "water efficient systems" for every of the selection criteria defined. As part of the characterization process, it is necessary to know drinking water demand patterns produced in the building. To do this, a water consumption audit can be performed, for the existing buildings, or results of similar buildings can be extrapolated, in the event that the building were a new construction that is going to be equipped with water efficient systems. The thesis shows how to carry out an audit of water consumption of the building. Also, some studies of water demand patterns in residential buildings are set. A self-done study on water patterns demands in the area of Valencia is presented. For the economic viability of implementing water saving systems it is very important that the size of all its equipments are as tight as possible to the use made of them in the building. Therefore, a study of the optimal and economic dimensioning of rain water harvesting systems has been made. It has also been theoretically studied the generating capacity of water condensation in air conditioning systems, for its use in water supply facilities. This information is used for equipment sizing of this water saving system. As there was no verified information on the validity of the theoretical method, measurements have been performed to contrast them. Finally, in this thesis measurements, studies, analysis, and equipment characterization, had been performed to make available a complete methodology for multi-criteria selection of the most suitable water efficient systems to equip a given building. / [ES] RESUMEN Es una realidad que en nuestro entorno existe un déficit hídrico que afecta tanto al consumo agrícola de agua dulce como al consumo urbano de agua potable. Las condiciones ambientales de cambio climático agravarán la situación en los próximos años. La gestión eficiente de los recursos hídricos es, y será, un tema importante para la sociedad que debe ser abordado desde un punto de vista social y tecnológico. Aunque el consumo no agrícola supone sólo una 30% de la demanda total de agua dulce, es el uso urbano del agua, que consume la mayor parte de ese porcentaje, el más preocupante por cuanto afecta directamente a las condiciones de vida de las personas. A la escasez de recursos hídricos se responde desde dos perspectivas. Por un lado el aumento de la oferta, a través de un aumento de las captaciones, trasvases desde cuencas excedentarias, o desalación. Por otro lado la reducción o gestión eficiente de la demanda. Es desde este enfoque desde donde se desarrolla este trabajo de investigación. El objetivo de la tesis doctoral es desarrollar una metodología para la selección de los sistemas de ahorro de agua potable más adecuados para equipar en un edificio. El proceso de selección se plantea desde dos aproximaciones, correspondiendo cada uno de ellos a un uso diferente del edificio. Para los edificios destinados a desarrollarse una actividad productiva se utiliza un método de selección coste-beneficio. Para el resto de edificios se utiliza un método de selección multicriterio. Para esta situación se ha optado por aplicar el método del proceso analítico jerárquico a la selección de sistemas de ahorro de agua. Para la aplicación de la selección multicriterio, se han definido una serie de criterios a tener en cuenta: ahorro de agua, ahorro de energía, impacto socio-ambiental, diseño, y viabilidad económica. Cada dispositivo o sistema de ahorro de agua debe ser caracterizado en base a cada uno de estos criterios. En la tesis se ha desarrollado la forma de caracterizar los denominados "sistemas de hidroeficiencia" para cada uno de los criterios de selección definidos. Como parte del proceso de caracterización, es necesario conocer la forma de consumir agua potable que se produce en el edificio. Para ello se puede realizar una auditoría de demandas, en el caso que el edificio exista, o se debe extrapolar resultados de edificios similares, en caso que el edificio sea un edificio de nueva planta que se quiere equipar con los sistemas de hidroeficiencia, ya de partida. En la tesis se indica cómo llevar a cabo una auditoría del consumo de agua del edificio. Igualmente se exponen algunos estudios de patrones de consumo en edificios de viviendas, y se presenta un estudio propio sobre patrones de demanda en la zona de Valencia, para la que no existía información. Para la viabilidad económica de la implantación de los sistemas de ahorro tiene gran importancia que su tamaño sea lo más ajustado posible al uso que se hace de ellos en el edificio. Por ello, se ha hecho un estudio del dimensionado óptimo y económico de los sistemas de aprovechamiento de aguas pluviales. Igualmente se ha estudiado de forma teórica la capacidad de generación de agua de condensación de los sistemas de climatización, para su aprovechamiento en las instalaciones de suministro de agua. Dicha información se utiliza para el dimensionado de los equipos de ese sistema de hidroeficiencia. Como no había información contrastada sobre la validez del método teórico, se han realizado mediciones para contrastarlos. Con todo, en la tesis que se presenta se han realizado las mediciones, estudios, análisis y caracterización de equipos necesarios para que se disponga de una metodología completa para la selección multicriterio de los sistemas de hidroeficiencia más adecuados para equipar un determinado edificio. / [CA] RESUM És una realitat que en el nostre entorn hi ha un dèficit hídric que afecta tant el consum agrícola d'aigua dolça com al consum urbà d'aigua potable. Les condicions ambientals de canvi climàtic agreujaran la situació en els pròxims anys. La gestió eficient dels recursos hídrics és, i serà, un tema important per a la societat que ha de ser abordat des d'un punt de vista social i tecnològic. Encara que el consum no agrícola suposa només una 30% de la demanda total d'aigua dolça, és l'ús urbà de l'aigua, que consumix la major part d'eixe percentatge, el més preocupant ja que afecta directament les condicions de vida de les persones. A l'escassetat de recursos hídrics es respon des de dos perspectives. Per un costat l'augment de l'oferta, a través d'un augment de les captacions, transvasaments des de conques excedentàries, o dessalatge. Per un altre costat la reducció o gestió eficient de la demanda. És des d'este enfocament des d'on es desenrotlla este treball d'investigació L'objectiu de la tesi doctoral és desenrotllar una metodologia per a la selecció dels sistemes d'estalvi d'aigua potable més adequats per a equipar en un edifici. El procés de selecció es planteja des de dos aproximacions, corresponent cada un d'ells a un ús diferent de l'edifici. Per als edificis destinats a desenrotllar-se una activitat productiva s'utilitza un mètode de selecció cost-benefici. Per a la resta d'edificis s'utilitza un mètode de selecció multicriterio. Per a esta situació s'ha optat per aplicar el mètode del procés analític jeràrquic a la selecció de sistemes d'estalvi d'aigua. Per a l'aplicació de la selecció multicriterio, s'han definit una sèrie de criteris a tindre en compte: estalvi d'aigua, estalvi d'energia, impacte socioambiental, disseny, i viabilitat econòmica. Cada dispositiu o sistema d'estalvi d'aigua ha de ser caracteritzat basant-se en cada un d'estos criteris. En la tesi s'ha desenrotllat la forma de caracteritzar els denominats "sistemes de hidroeficiencia" per a cada un dels criteris de selecció definits. Com a part del procés de caracterització, és necessari conéixer la forma de consumir aigua potable que es produïx en l'edifici. Per a això es pot realitzar una auditoria de demandes, en el cas que l'edifici existisca, o s'ha d'extrapolar resultats d'edificis semblants, en cas que l'edifici siga un edifici de nova planta que es vol equipar amb els sistemes de hidroeficiencia, ja de partida. En la tesi s'indica com dur a terme una auditoria del consum d'aigua de l'edifici. Igualment s'exposen alguns estudis de patrons de consum en edificis de vivendes, i es presenta un estudi propi sobre patrons de demanda en la zona de València, per a la que no existia informació. Per a la viabilitat econòmica de la implantació dels sistemes d'estalvi té gran importància que la seua dimensió siga el més ajustat possible a l'ús que es fa d'ells en l'edifici. Per això, s'ha fet un estudi del dimensionat òptim i econòmic dels sistemes d'aprofitament d'aigües pluvials. Igualment s'ha estudiat de forma teòrica la capacitat de generació d'aigua de condensació dels sistemes de climatització, per al seu aprofitament en les instal·lacions de subministrament d'aigua. La dita informació s'utilitza per al dimensionat dels equips d'eixe sistema de hidroeficiencia. Com no hi havia informació contrastada sobre la validesa del mètode teòric, s'han realitzat mesuraments per a contrastar-los. Amb tot, en la tesi que es presenta s'han realitzat els mesuraments, estudis, anàlisi i caracterització d'equips necessaris perquè es dispose d'una metodologia completa per a la selecció multicriterio dels sistemes de hidroeficiencia més adequats per a equipar un determinat edifici. / López Patiño, G. (2016). Análisis y caracterización de las instalaciones interiores de suministro de agua desde el punto de vista de ahorro [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61476
79

Performance of Large-Scale Gezira Irrigation Scheme and its Implications for Downstream River Nile Flow

Al Zayed, Islam 30 June 2015 (has links) (PDF)
Policy makers adopt irrigated agriculture for food security, since irrigation doubles crop production. Therefore, the development of large irrigation systems has a long history in many places worldwide. Although large-scale irrigation schemes play an important role in improving food security, many schemes, especially in Africa, do not yield the expected outcomes. This is related to poor water management, which is generally due to a lack of effective evaluation and monitoring. The objective of this study, therefore, is to propose a new methodology to assess, evaluate and monitor large-scale irrigation systems. Information on irrigation indicators is needed to enable the evaluation of irrigation performance. The evaluation is the first and the most significant step in providing information about how it is performing. After reviewing extensive literature, a list of indicators related to the performance of irrigation, rainwater supply and productivity is suggested. The irrigation efficiency indicators Relative Irrigation Supply (RIS) and Relative Water Supply (RWS) are selected. Potential rainwater supply to crops can be tested based on the Moisture Availability Index (MAI) and the Ratio of Moisture Availability (RMA). Water productivity can be assessed by Crop Yield (Y) and Water Use Efficiency (WUE). However, the central problem facing large-scale irrigation schemes is always the lack of data, which calls for the development of a new method of data acquisition that allows evaluation and monitoring. Remote Sensing (RS) technology makes it possible to retrieve data across large areas. Two different approaches via RS, the Normalized Difference Vegetation Index (NDVI) and Actual Evapotranspiration (ETa), can be utilized for monitoring. The well-known Vegetation Condition Index (VCI), derived from the NDVI, is modified (MVCI) to allow a qualitative spatio-temporal assessment of irrigation efficiency. MVCI takes into account crop response to water availability, while ETa indicates whether water is used as intended. Furthermore, the assessment of the possible hydrological impact of the irrigation system should be considered in the evaluation and monitoring process. The Sudanese Gezira Scheme of 8,000 square kilometers in the Nile Basin, where performance evaluation and monitoring are absent or poorly conducted, is no exception. This research takes the large-scale irrigation of the Gezira Scheme as a case study, as it is the largest scheme, not only in the Nile Basin but also in the world, under single management. The first long-term historical evaluation of the scheme is conducted for the period 1961–2012 rather than only on a short-time scale as is the common practice. An increase in RIS and RWS values from 1.40 and 1.70 to 2.23 and 2.60, respectively, since the 1993/94 season shows decreasing irrigation efficiency. MAI and RMA for summer crops indicate a promising rainfall contribution to irrigation in July and August. The Gezira Scheme achieves low yield and WUE in comparison to many irrigation schemes of the globe. Low productivity is mainly due to poor distribution and irrigation mismanagement. This is indicated by the 15-year MVCI spatio-temporal analysis, which shows that the northern part of the scheme experiences characteristic drought during the summer crop season. Although MVCI can be considered a monitoring tool, the index does not deduct the soil water content, and water could be wasted and available in other ways (e.g. water depressions). Spatio-temporal information for ETa is required to better quantify water depletion and establish links between land use and water allocation. However, several RS models have been developed for estimating ETa. Thus, improving the understanding of performance of such models in arid climates, as well as large-scale irrigation schemes, is taken into account in this study. Four different models based on the energy balance method, the Surface Energy Balance Algorithm for Land (SEBAL), Mapping EvapoTranspiration at High Resolution with Internalized Calibration (METRIC™), Simplified Surface Energy Balance (SSEB) and MOD16 ET are applied in order to determine the optimal approach for obtaining ETa. Outputs from these models are compared to actual water balance (WB) estimates during the 2004/05 season at field scale. Several statistical measures are evaluated, and a score is given for each model in order to select the best-performing model. Based on ranking criteria, SSEB gives the best performance and is seen as a suitable operational ETa model for the scheme. SSEB subsequently is applied for summer and winter crop seasons for the period 2000–2014. Unfortunately, one of the limitations faced in the current research is the absence of validation data on a regional scale. Therefore, the assessment focuses on spatial distribution and trends rather than absolute values. As with the MVCI distribution, the seasonal ETa for the Gezira Scheme is higher in the southern and central parts than in the northern part. This confirms the robustness of the developed MVCI. To avoid using absolute values of ETa, the ratio of ETa from agricultural areas (ETagr) to the total evapotranspiration (ET) from the scheme (ETsum) is calculated. The ETagr/ETsum ratio shows a descending trend over recent years, indicating that the water is available but not being utilized for agricultural production. This study shows that SSEB is also useful for identifying the location of water losses on a daily basis. Around 80 channels are identified as having leakage problems for the 2013/14 crop season. Such information is very useful for reducing losses at the scheme. In addition, Rainwater Harvesting (WH) is addressed and found to be applicable as an alternative solution for accounting for rainfall in irrigation. It is seen that these management scenarios could save water and increase the overall efficiency of the scheme. It is possible to save 68 million cubic meters of water per year when the overall irrigation efficiency of the scheme is improved by only 1%. A level of efficiency of 75% is predicted from the proposed management scenarios, which could save about 2.6 billion cubic meters of water per year. In conclusion, the present study has developed an innovative method of identifying the problems of large-scale schemes as well as proposing management scenarios to enhance irrigation water management practice. Improved agricultural water management in terms of crop, water and land management can increase food production, thereby alleviating poverty and hunger in an environmentally sustainable manner.
80

Laboratory Evaluation of Water-Repellent Soils for Water Harvesting

Fink, Dwayne H. 20 April 1974 (has links)
From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / Reported are laboratory evaluations to screen water-repellent materials and treatments before testing them in the field. Water repellency tests were conducted on paraffin wax, a wax emulsion and silicon, lard, and a liquid dust suppressant. Six water repellency tests showed that the high rates of paraffin wax and all rates of the dust suppressant produced highly water-repellent soil surfaces. The six water repellency tests were: (1) the aqueous-alcohol drop test for determination of the 90 degree surface tension for a porous solid, (2) the water drop penetration time test, (3) the relative height of a large sessile water drop resting on the smoothed, treated soil surface, (4) and (5) the presence and persistence of air bubbles trapped between the soil-water interface, and test (6) was made to note whether the large sessile water drop from test (3) would infiltrate the soil or evaporate. Tests (3), (4), and (5) proved the most useful of the six methods for measuring water repellency. Soil type had no significant influence on degree of water repellency as measured in the laboratory by these six tests.

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