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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.
101

Occurrence of per- and polyfluorinated alkyl substances (PFAS), including ultra-short-chain compounds. Seasonal variation in rainwater from the Swedish west coast

Jansson, Felicia January 2019 (has links)
Per- and polyfluoroalkyl substances (PFAS) are a group of highly fluorinated compounds which comprises of more than 4700 substances. A smaller number of those substances is rou-tinely measured, usually the short (C4-C7) and long chain PFAS (>C7). Detection of PFAS in different water matrices including wet precipitation have been done previously in a limited number of studies, including ultra-short chain compounds (C1-C3). Ultra-short chain com-pounds have however not been investigated to a larger extent. In this study, twelve rainwater samples from Råö have been analysed, each representing a composite sample of one month. Long (C8-C18), short as well as ultra-short chain PFAS have been included in the analysis. Long and short chain compounds were analysed with ultra-performance liquid chromatography tan-dem mass spectrometer (UPLC-MS/MS) and ultra-short chain compounds with ultra-perfor-mance convergence chromatography tandem spectrometer (UPCC-MS/MS). Long and short-chain PFAS had a total detectable concentration of 5.1-110 ng/L. A seasonal trend was also studied, which showed a significant difference when performing a Kruskal Wallis test in meas-ured total mean long and short chain PFAS concentration. Dunnet´s test indicated a significant difference between all the seasons. Highest concentrations were measured during summer and lowest during winter. Ultra-short chain compounds analysed by UPCC MS/MS had a total concentration between 16-410 ng/L. No significant difference in total ultra-short PFAS mean concentration could be seen between different seasons using a Kruskal Wallis test. The total PFAS concentration in the rain samples ranged from 28 to 540 ng/L, where ultra-short chain PFAS contributed to 58-92 % of the total concentration. Which makes them an important group to include in future measurements of PFAS in water samples and especially in rainwater sam-ples.
102

Microbial and physico-chemical assessment of on-site water supply systems

Kolam, Joel, University of Western Sydney, College of Science, Technology and Environment, School of Environment and Agriculture January 2003 (has links)
The utilisation of rainwater tanks and bore wells are very common in many parts of rural Australia and Papua New Guinea. In Australia, on-site collection and storage of potable water for domestic use is carried out by approximately 30.4 percent of the rural population while 90% of the population in Papua New Guinea access water from on-site collection and storage of potable water. Few studies have monitored the quality of such water supplies on a seasonal and event associated basis. The aim of this study was to evaluate the microbiological and physio-chemical properties of the on-site domestic water supply systems and various factors that may influence characteristics of the water. It aimed to evaluate the relationship of microbiological and physio-chemical characteristics in the water supply systems. 14 rainwater tanks, 4 bore well and 10 reticulated water supply sites in Hawkesbury District, NSW Australia were investigated. Characteristics of the sites physical situation and natural environmental condition were considered to be similar to on-site water supply situations in Papua New Guinea. The results and techniques of the study will be used as a model in Papua New Guinea in the assessment of water quality issues. As the study showed that the quality of water in rainwater tanks was below WHO guideline recommendations on numerous instances, it was proposed that water treatment and maintaining the cleanliness of roof catchments, gutters and tanks should be addressed for domestic use systems. A protocol for sampling, assessment and data interpretation of faecal indicator bacteria populations in domestic catchment supply systems was developed and demonstrated / Master of Science (Hons)
103

A minor field study for combined rainwater andpond harvesting system and purification technology in the village Macedonia, Amazon basin, Colombia

Tjus, Anna, Johansson, Annie January 2008 (has links)
This study is a bachelor degree project which focuses on the lack of safe drinking water in a small village known as Macedonia in the Amazon basin in Colombia. The inhabitants of the village are 850 to the number and have never had access to safe drinking water. To solve this problem a system has been built where the rainwater is harvested in a pond and also from a church roof During the dry season the rainwater in the pond is harvested and pumped into sedimentation tanks. Thereafter, the water is led into the sand filtration tanks. While during the rain season, the rainwater is harvested from a church roof which is situated at highest level in Macedonia. The water is stored in a cistern and then it is led into sand filtration tanks via pipes. This means that the pond water and rainwater are never mixed before entering the filtration tanks. The sand filtration tanks contain about 1000 mm thick layer of sand and under it, a layer of gravel which is placed in the bottom of the tank. It takes a while for the water to be filtered through the sand filtration tank. Afterwards, it is led into the final tank, where the drinking water is stored ready to be used. The method of using slow sand filtration (SSF) is suitable for small scale-projects and therefore for this project a good idea for making drinking water. SSF requires no mechanical power or replaceable parts, this is why the technique is good for purifying water in developing and isolated areas. The result of the system is water with satisfied quality running through pipes and taps, ready to be consumed.
104

Nurturing Landscapes: Creating educational rainwater management systems on school grounds

Orr, Catherine 28 September 2015 (has links)
This research poses two questions: How, through collaboration and thoughtful design practices, can rainwater management systems on school grounds be developed as resources for learning? And, what can these systems contribute to the development of more sustainable urban rainwater management? The research was conducted through a literature review, the analysis of three case studies and a pilot project. The research points to the potential for schools to act as a centralizing figure, enabling a community collaboration to occur, with the aim of implementing shared goals. This process generated knowledge, spread awareness and built relationships among the community. The school’s participation in this process was key to creating place-based, engaging solutions. The rainwater systems must be multi-functional and contribute to the learning environment by building on the school’s educational philosophy. The four projects offer different scenarios for creating rainwater management systems that engage students through both hands-on learning and play. / Graduate / 0390 / orr.cat@gmail.com
105

Equitable cost allocation for rainwater harvesting system : framework analysis : case of Austin,TX

Kim, Hyun Woo 25 July 2011 (has links)
The limitation of urban water supplies is becoming worse each year. Several studies estimate that 2 billion of the world’s population will suffer from water scarcity by 2050; and urbanization rates is placing an even greater challenge in providing the infrastructure needed to serve growing populations. At this point, rainwater may be considered as the most critical, untapped water resource in a global aspect. Rainwater Harvesting Systems (RWHS) have tremendous potential, not only to provide sufficient water supply, but also to serve as a valuable stormwater management tool. Despite these benefits, RWHS is still not popular among ordinary people in urban situations, due mostly to high installation costs. This study aims to explore the equitable cost reallocation of residential rainwater harvesting systems between the urban utility, land developer and homebuilder, and individual homeowner sectors. It may be possible to redistribute the cost equitably among the parties based on potential benefits received,thereby making RWHS more affordable and more viable as a new water supply for urban areas. / text
106

Rainwater harvesting systems and their influences on field scale soil hydraulic properties, water fluxes and crop production /

Kosgei, Job Rotich. January 2009 (has links)
Thesis (Ph.D.) - University of KwaZulu-Natal, Pietermaritzburg, 2009. / Full text also available online. Scroll down for electronic link.
107

A minor field study for combined rainwater andpond harvesting system and purification technology in the village Macedonia, Amazon basin, Colombia

Tjus, Anna, Johansson, Annie January 2008 (has links)
<p> </p><p>This study is a bachelor degree project which focuses on the lack of safe drinking water in a small village known as Macedonia in the Amazon basin in Colombia. The inhabitants of the village are 850 to the number and have never had access to safe drinking water. To solve this problem a system has been built where the rainwater is harvested in a pond and also from a church roof</p><p>During the dry season the rainwater in the pond is harvested and pumped into sedimentation tanks. Thereafter, the water is led into the sand filtration tanks. While during the rain season, the rainwater is harvested from a church roof which is situated at highest level in Macedonia. The water is stored in a cistern and then it is led into sand filtration tanks via pipes. This means that the pond water and rainwater are never mixed before entering the filtration tanks.</p><p>The sand filtration tanks contain about 1000 mm thick layer of sand and under it, a layer of gravel which is placed in the bottom of the tank. It takes a while for the water to be filtered through the sand filtration tank. Afterwards, it is led into the final tank, where the drinking water is stored ready to be used.</p><p>The method of using slow sand filtration (SSF) is suitable for small scale-projects and therefore for this project a good idea for making drinking water. SSF requires no mechanical power or replaceable parts, this is why the technique is good for purifying water in developing and isolated areas.</p><p>The result of the system is water with satisfied quality running through pipes and taps, ready to be consumed.</p><p> </p><p> </p><p> </p><p> </p>
108

AVALIAÇÃO DA QUALIDADE DA ÁGUA DA CHUVA E DA VIABILIDADE DE SUA CAPTAÇÃO E USO / EVALUATION OF RAINWATER QUALITY AND FEASIBILITY OF ITS COLLECTION AND USAGE

Hagemann, Sabrina Elicker 04 March 2009 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / This paper aims to evaluate the rainwater quality in city of Santa Maria RS, identify the most suitable usages for it and to study the technical feasibility of its collection, through a reservoir dimension for exploitation. Two areas of study were chosen with different characteristics referring to their occupation. One of these areas is located next to RST 287 and the other is in Universidade Federal de Santa Maria campus. The rainwater was collected directly from atmosphere and from roofs, in order to analyze the changes in its quality after the passage for collection area. Each sample was divided in five compartments for collecting and storing separately the first five millimeters of rain. The characteristics of rainwater quality were evaluated through the following parameters: pH, electrical conductivity, turbidity, BOD5, COD, total solids, suspended solids, dissolved solids and Escherichia coli. In some events it was also analyzed: color, alkalinity, hardness, chlorides, iron, manganese, phosphate, ammonium, nitrate and sulfate. For storage reservoir dimension it was used a method proposed by Mierzwa et al (2007) and the results were compared to methods proposed by NBR 15527/07. It was observed that the rainwater quality has changed after its passage for collection area. In raw state, the rainwater could be used to non-potable purposes as recreation of primary contact, irrigation of vegetables, parks, gardens, sport and leisure fields, after the discard of two millimeters initial. If the rainwater was treated, it obtain quality compatible with other uses as toilet flushing. In relation to storing reservoir, it was evident that the most profits for an efficient attendance to a demand occur by a volum of 5.000 liters, for a daily demand of 529 liters. / Este trabalho teve como objetivos avaliar a qualidade da água da chuva na cidade de Santa Maria RS, identificar os usos mais apropriados para a mesma e estudar a viabilidade técnica de sua captação, através do dimensionamento de um reservatório para aproveitamento. Foram escolhidas duas áreas de estudo com características distintas quanto à ocupação. Uma das áreas está localizada próxima à RST 287 e a outra no Campus da UFSM. A água da chuva foi coletada diretamente da atmosfera e de telhados, a fim de analisar as alterações em sua qualidade após a passagem pela área de captação. Cada amostrador foi dividido em cinco compartimentos, para coletar e armazenar separadamente os cinco primeiros milímetros de chuva. As características de qualidade da água da chuva foram avaliadas através dos parâmetros: pH, condutividade elétrica, turbidez, DBO5, DQO, sólidos totais, sólidos suspensos, sólidos dissolvidos e Escherichia coli. Em alguns eventos foram analisados também: cor, alcalinidade, dureza, cloretos, ferro, manganês, fosfato, amônia, nitrato e sulfato. Para o dimensionamento do reservatório de armazenamento foi utilizado o método proposto por Mierzwa et al (2007) e comparados os resultados com métodos propostos pela NBR 15527/07. Observou-se que a qualidade da água da chuva é alterada após sua passagem pela área de captação. No estado bruto as águas pluviais podem ser utilizadas para fins não-potáveis, como recreação de contato primário, irrigação de hortaliças, de plantas frutíferas, de parques, jardins, campos de esporte e lazer, após o descarte de 2 mm iniciais. Se for tratada a água de chuva adquire qualidade compatível com outros usos, como descargas de bacias sanitárias. Quanto ao reservatório de armazenamento constatou-se que os maiores ganhos na eficiência ao atendimento à demanda ocorrem até o volume de 5.000 litros, para uma demanda diária de 529 litros.
109

Captação residencial de água da chuva para fins não potáveis em Porto Alegre : aspectos básicos da viabilidade e benefícios do sistema

Mano, Rafael Simões January 2004 (has links)
A construção civil ocupa uma posição muito importante no contexto da degradação ambiental, a qual o Planeta vem assistindo nas últimas décadas, sendo responsável por uma parcela significativa do consumo total de recursos naturais. Além disso, considerando uma análise do ciclo de vida de edifícios, a fase de uso dos mesmos tem tomado crescente importância no impacto total gerado pela edificação. Alterações no ciclo hidrológico e poluição dos meios hídricos são exemplos de importantes impactos gerados pelo uso de edificações. Em meio urbano são co-responsáveis também pelas cheias e inundações, que com freqüência geram importantes perdas humanas e materiais. Soluções técnicas alternativas têm sido desenvolvidas e apresentadas pelo mundo. Porém mostram-se pouco adaptáveis às condições nacionais, entre outros, por causa do aspecto econômico, muito importante em países subdesenvolvidos como o Brasil. Neste sentido, a pesquisa objetiva uma caracterização dos benefícios diretos e indiretos decorrentes da implantação de sistemas de captação e aproveitamento de água da chuva, para utilização não potável, em meio urbano, principalmente sob o aspecto econômico. Para tanto, revisa alguns aspectos relativos à contextualização e à viabilidade técnica destes sistemas, apresentando desde o tema da água no planeta até suas interações mais objetivas, no meio urbano. Um estudo experimental, sobre a edificação denominada Protótipo Alvorada, é desenvolvido em paralelo, a fim de ilustrar e balizar os estudos das variáveis dimensionais do sistema, dos números de chuva, neste caso para Porto Alegre/RS, e também o levantamento dos principais tipos e componentes de sistemas existentes. Os resultados para os benefícios diretos, sobre o aspecto econômico, demonstram em geral que o custo de implantação do sistema é o maior entrave à sua aplicação. Este fato deve-se, em grande parte à disponibilidade do recurso em Porto Alegre, entregue dentro das residências por um baixo custo. O estudo em torno dos benefícios indiretos revelou o potencial do sistema como auxiliar na drenagem urbana. Dependendo ainda de estudos mais aprofundados, o sistema conta com a possibilidade receber subsídio público para sua implantação, gerando economia para o mesmo e maximizando também o benefício direto. / During the past few decades the building industry was becoming increasingly responsible for a large portion of environmental degradation. In addition, considering the life cycle analysis of buildings, the building utilization phase is gaining importance in building environmental impact. Alterations in the water cycle, often resulting in human and economic loses because of urban flooding, is an example where the building utilization phase plays a significant role in environmental degradation. One answer to these problems is alternative technical solutions that are being developed and presented to environmental forums throughout the world; however, most of the alternative solutions are not economically feasible for sub-developed countries like Brazil. The objective of this research is to characterize the direct and indirect benefits provided by residential urban rainwater catchment systems and the implementation for non-potable use in the urban environment for economic gain. Towards this goal, the dissertation reviews some contexts and technical viability concerns about urban water interactions and drainage systems. A study, developed simultaneously with the research, was conducted on the building Protótipo Alvorada to gain an understanding of the variables of system dimensions, rain water distribution and volume. The study also explores existing systems, principal types of systems and components of existing systems. The results of this study have shown that, from an economic standpoint, the cost of system implementation is generally the main barrior to implemention of rainwater catchment systems. One reason that rainwater catchment systems are not economically feasible choice for the city of Porto Alegre is in large part due to the availability of potable water in the city. Water distribution to residences within the city is very inexpensive and widely available. The study about the indirect benefits of rainwater catchment systems has shown the potential of systems to help alleviate urban drainage problems. Despite the necessity for further studies, the feasibility of system implementation here in Porto Alegre/RS counts on the possibility of initial public funding in order to maximize the direct benefits of catchment systems. Installation of rainwater catchment systems would ultimately save money for the municipal government of Porto Alegre.
110

Impacts of scaling up water recycling and rainwater harvesting technologies on hydraulic and hydrological flows

Bertrand, Nathalie Marie-Ange January 2008 (has links)
In recent years, the increasing awareness of scarcity of water resources, indications of likely climate variability, and the increasing pressure to use available fresh water resources more efficiently have together reinforced the need to look at infrastructure solutions with due regard to environmental considerations and social impacts, present and future. There is a vital need to apply an integrated approach to catchment management to implement sustainable solutions to resolve issues such as water supply and sewerage, drainage and river flooding. Many potentials solutions are available to control water demand and manage flood problems. Greywater recycling and rainwater harvesting are novel technologies. However, their catchment scale impacts on hydraulic and hydrological flows are poorly understood. The research aim is to identify the hydrologic and hydraulic impacts of scaling up such technologies at catchment scale. For this particular study, a computer simulation model will be used to evaluate how increasing urbanisation, climate change and the implementation of greywater recycling and rainwater harvesting may alter the water balance within a representative catchment. To achieve these aims data from the Carrickmines catchment in Ireland have been collected; a simulation model has been adapted to carry out the study, the model has been calibrated and validated, results have been analysed, and finally, a sensitivity analysis has been carried out. The results show that rainwater harvesting systems are comparatively more effective than greywater recycling techniques in reducing flood frequency and intensity. Under five year return period rainfall events, the implementation of rainwater harvesting at any scale and number of units is a useful technique to control river flow and floods. However, the study also shows that under extreme conditions the efficiency of rainwater harvesting systems decreases. The study concludes that implementing the two technologies within a single catchment is not a solution to several forms of hydrological problem. The study shows that implementing rainwater harvesting or re-use technologies are a very useful way to protect local freshwater reserves and therefore conserve our environment.

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