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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.
441

Tecnologias de reúso aplicadas ao abastecimento de água potável e industrial da Baixada Santista / Reuse technologies applied to the drinking water and industrial supply of Baixada Santista

Carlos Lopes dos Santos 22 December 1992 (has links)
Nesta tese, é apresentada uma revisão bibliográfica de reuso potável indireto e reuso industrial. Examina-se na prática dois estudos de caso, um de reuso industrial e um de reuso potável com aplicação para a Baixada Santista. O de reuso industrial refere-se ao projeto de fornecidmento de água oriunda da represa Billings, que com pequeno tratamento é oferecida às indústrias de Cubatão para fins não nobres como por exemplo, refrigeração, aquecimento a vapor, rega de jardins, abatimento de material particulado. etc. Quanto ao de reuso potável a apresentação se faz através de experimentos de laboratórios, examinando-se trihalometanos (THM) e o poder desinfetante de alguns produtos químicos após passagem da água por carvão ativado granular e outros tratamentos, e suas consequências na rede de abastecimento de água. Concluiu-se que o melhor ponto de instalação da captação para o abastecimento de água industrial fica entre os canais de fuga da usina Henry Borden, em Cubatão, por seu melhor desempenho econômico e pela possibilidade de atendimento no futuro a outras indústrias. Ainda, se comprovou a eficiência do carvão ativado granular na remoção dos precursores de THM e o baixo poder desinfetante da cloramina. / There is in this thesis, a small literature revision about the matter, mainly about indirect potable reuse and industrial reuse. In the practical part they are examined in two cases, industrial reuse and potable reuse, both for the Santos Basin. In the Industrial Reuse, there is a project to distribute industrial water to Cubatão industries, using water from Billings after a small treatment. This water is to be used in refrigeration of steel or to boil water to obtain steam or put in solid material to avoid air pollution, etc. In Potable Reuse, there are many laboratory experiences about THM and desinfection by many chemical products and their consequences in distribuition of water. In conclusion, the best place for ínstalation of the collection of water is located between the Henry Borden Power Plant Channels, in Cubatão, for it\'s superior economic performance and for the possibility to support other industries in the future. It has already confirmed the efficiency of the granular activated carbon to remove THM precursors and its inability to desinfect ammonia chlorine.
442

A influência da variabilidade climática na qualidade da água do reservatório Guarapiranga e possíveis impactos à saúde / The influence of climate variability on water quality of the reservoir Guarapiranga and possible impacts on health

Sofia Lizarralde Oliver 11 September 2013 (has links)
O objetivo deste estudo foi verificar se existe associação entre a qualidade da água para abastecimento público proveniente do Sistema Guarapiranga e o clima da Região Metropolitana de São Paulo (RMSP). Realizou-se a análise dos dados meteorológicos adquiridos junto à Estação Meteorológica do Instituto de Astronomia, Geofísica e Ciências Atmosféricas da Universidade de São Paulo (IAG/USP) e dos resultados de análises laboratoriais da água do Reservatório Guarapiranga adquiridos junto à Companhia de Saneamento Básico do Estado de São Paulo (SABESP). A partir da relação entre as variáveis observadas em gráficos e testes de associação/correlação, verificou-se a associação/correlação entre a densidade de cianobactérias e as variáveis meteorológicas na RMSP, tais como temperatura atmosférica (T°C), insolação (horas de brilho do sol) e precipitação (mm). Para analisar as interações e relações de cada uma das variáveis meteorológicas em relação à densidade de cianobactérias, foram feitos diferentes recortes de tempo. Todos os dados foram organizados em Planilhas Microsoft® Excel 15.0 (Office 2013) e analisados em gráficos e testes estatísticos. Segundo os resultados deste estudo, a densidade de cianobactérias apresenta associação positiva com os períodos de chuva e temperaturas elevadas (outubro a março) e, juntamente com as análises de dados climáticos dos últimos 42 anos, verificou-se que as condições climáticas ideais para a proliferação de cianobactérias no Reservatório Guarapiranga vêm se acentuando ao longo das últimas quatro décadas, particularmente nos últimos 20 anos. Conclui-se que há indicações de que a densidade de cianobactérias no Reservatório do Sistema Guarapiranga tenha relação temperaturas mais elevadas e pluviosidade e que a proliferação de cianobactérias pode aumentar caso se mantenha a tendência do clima. / This study has aimed to verify if there is a relation between the quality of the water in the Guarapiranga System (reservoir), as it is supplied to the inhabitants, and the climate in the São Paulo Metropolitan Area (RMSP). We have analyzed the data obtained from the Weather station of the Astronomy, Geophysics and Atmospherical Sciences Institute at the University of São Paulo (IAG/USP), as well as the results of the reservoir water laboratory analysis, provided by the basic sanitation company in the State of São Paulo (SABESP). Cyanobacteria density and meteorological variables in the RMSP, such as atmospheric temperature (ToC), insolation (daily solar irradiance) and precipitation (mm), were verified through association/correlation tests and graphics. To analyze the interaction and relation between cyanobacteria density and meteorological variables, were have resorted to different time spans. Data was organized in Microsoft® Excel 15.0 (Office 2013) tables and graphics, and statistically analyzed. According to this study results, cyanobacteria density might be positively associated to periods of rainfall and high temperatures (October to March). Also, along with data analysis of climate throughout the last 42 years, we have observed that the ideal climate conditions for cyanobacteria proliferation in the Guarapiranga reservoir have been stressed in the last four decades, especially during the last 20 years. Therefore, frequency and intensity of cyanobacteria proliferation in the Guarapiranga reservoir may increase according to climate trend in the RMSP.
443

Engineering the Byzantine water supply of Constantinople : mapping, hydrology and hydraulics of the long aqueducts outside the city

Ruggeri, Francesca January 2018 (has links)
The Water Supply of Byzantine Constantinople is one of the most outstanding achievements of hydraulic engineering from the Roman world. Working entirely as a gravity-fed system, this infrastructure relied on hundreds of kilometres of masonry channels, winding along the hills of Turkish Thrace and carrying water to Constantinople across different watersheds. The Water Supply was built in two main phases: the first in the mid-fourth century, following the foundation of Constantinople in 330 AD; and the second in the early fifth century. It is not clear whether the aqueducts from these two phases worked independently or as a single system, yet the scale of this would have been colossal, reaching lengths of 450 km between the two aqueducts. However, a full and close understanding of its hydraulic design and function has until now been missing. As such, this investigation aims to: (1) establish a clear route for the aqueducts, both in terms of length and gradient (mapping); (2) determine likely volumes of water entering the system at the various intakes (hydrology); and (3) evaluate its hydraulic behaviour and flow characteristics (hydraulics). While previous work on similar Roman aqueducts yielded only estimates of maximum capacity, this work delves into the engineering of the ancient infrastructure to provide a more realistic assessment of theWater Supply discharge to the City. The physical configuration of the aqueducts is reinterpreted based on the latest archaeological records comprising Global Positioning System (GPS) measurements and field observations, and validated against modern satellite terrain data in a Geographic Information System (GIS). Refined estimates of length and gradient are proposed, along with a reassessment of all channel observations, bridges and tunnels along the system. It is found that the total length of the aqueducts would have been around 426 km if they operated as a single system, and up to 565 km if they continued in parallel all the way to Constantinople; the gradient of the system would have been well below 0.1% throughout, decreasing from upstream to downstream, with steeper slopes only at the intakes. To estimate reasoned inflow conditions for the Water Supply intakes at the time of its operation, modern spring flow records are investigated, and climatic changes from the Early Byzantine period are studied by means of Macrophysical Climate Modelling (MCM). Monthly and daily resolutions are addressed: monthly inflow data can capture the extent of the seasonal variations that may have occurred at the springs, accounting for karst hydrogeology; daily inflow data allows the study of flow attenuation in the Water Supply in the short term. Simplified models and engineering judgement are employed to recreate monthly and daily inflow series from limited modern data for karstic springs and weather stations in Thrace. The results from GIS mapping, combined with the proposed inflow scenarios, are used to develop open-channel flow modelling of the Water Supply at a global scale. Aqueduct flow is numerically simulated by means of both steady (monthly) and unsteady (daily) analysis using the river modelling software HEC-RAS. The system capacity and hydraulic performance are studied for the fourth and fifth century aqueducts operating either as parallel lines or joining into a single system. An estimation of water delivered to Constantinople is proposed for typical dry, average and wet years. Results of this work are employed in a parallel research investigation on the management and distribution of water within the ancient city.
444

Engineering exploration of the water supply system of Constantinople

Ward, Kate Alice January 2018 (has links)
Before this research study began, relatively little was understood of the water supply in Constantinople, particularly within the walls of the city. Archaeological work had focused on collecting details of 160 cisterns and a small number of channels and pipes were incidental finds in other excavations. Although no-one had considered the water supply in Constantinople as a whole, the evidence seemed to indicate a sophisticated water management system. With the available data fragmented, and the potential for more evidence limited to serendipitous finds associated with construction work, the only way to move the understanding of the water supply forward is to take a radically different perspective: civil engineers are well placed to envisage the water supply as a working system and make use of their modern design skills and tools to fill in the gaps between the fragmented data. This reimagining of the water supply system was driven by a key piece of knowledge: the water supply worked, and worked for many centuries. That fact, combined with the fragments of physical and literary evidence, the largely unchanged landscape and the fundamental physical laws governing gravity-fed water systems, are enough to start filling in the information to create a complete system. The core work in reimagining the water supply system has been developing an understanding of the physical infrastructure of the distribution system. Although the two most recent and comprehensive studies appeared to agree that there were about 159 cisterns in the city, close examination of the available data showed that there were actually 209 with the possibility of more. An evaluation of the aqueduct routes in previous studies highlighted inconsistencies with newly available evidence: alternative routes were designed that tied together the available evidence, providing a consistently downhill route, shorter and more straightforward to construct. Having established the number and spread of cisterns and the locations of the aqueducts, it was possible to create a network delivering water from the aqueduct channels to the cisterns for collection by the public. Consideration has also been given to what occurs at either end of this physical infrastructure. At the upstream end, quantifying and characterising the water source defines the water available to distribute and helps to indicate the purpose of the cisterns. At the downstream end, developing even a basic model of water consumption has enabled the distribution network to move from a static artefact to a system with a quantifiable purpose. The combination of the physical infrastructure, inflow data and demand assumptions in an agent-based model demonstrate that the decisions and assumption made within each element work together and allow a fourth element, management, to be considered. The agent-based model of the water supply enables consideration of a dynamic system and the exploration of a number of 'what if?' scenarios. This exploration concludes that the cistern-based distribution system probably developed because of fluctuations in inflow. It may have been possible for the city to use a merged arrangement on the Aqueduct of Valens inflow, but the burden of pro-active management required to make it successful suggests that a parallel arrangement is more likely. There was likely to be an interconnection between the two main aqueducts, which would have enabled the use of water stored in the largest open-air cisterns.
445

The causes and impact of water shortage on the households of Ga-Kgapane Township in the Limpopo Province

Machethe, Elliot Masoto January 2011 (has links)
Thesis (M.Dev.) --University of Limpopo, 2011 / Water shortage is a global problem. While other people in some parts of the world maybe enjoying enough supply of water others are faced with water shortage. South Africa is not an exception in this regard because some do not have access to water but rely on distance conveyance. Government is under constitutional obligation to supply this basic social and economic service. This study, therefore, aimed at investigating the causes of water shortage and the impact thereof on the household of Ga-Kgapane Township in Limpopo Province. This township falls under Greater Letaba Municipality in Modjadjiskloof. The data collected from four sections/localities of this Township showed that the area has a serious problem of water shortage. The lack of water according to the findings negatively affects the livelihoods and development of the people of Ga-Kgapane Township.
446

Assessment of the capacity of Masibambane donor funded non-governmental organizations (NGO's) to provide water services in the Limpopo Province

Matjuda, Mosibudi Agnes January 2010 (has links)
Thesis (M.Dev.) --University of Limpopo, 2010 / This study was undertaken in the Limpopo province, South Africa. Its aim was to assess the capacity of the NGOs that benefitted from Masibambane which is a donor funded programme and to examine the contributions that they are making towards addressing the water and sanitation challenges. This programme made funding available to capacitate the NGOs with the hope that they will assist the sector. Five NGOs which are operating in various districts in the province were included in the study. This was a qualitative study. Purposive sampling was used to select participants from NGOs, municipalities, Department of Water Affairs and communities. Primary data were collected through interviews, focused groups and observations in the field while secondary data were obtained from NGO and Water Affairs documents. The findings of this study revealed that The Mvula Trust and Tsogang Water and Sanitation NGOs have the capacity to implement both water and sanitation infrastructure projects at a village level. Operation Hunger‟s expertise regarding water infrastructure projects is on digging boreholes and installing hand pipes even though it diversified to include water conservation. Akanani Rural Development Association has the expertise of building sanitation facilities while Thlavhama Training Initiative is still learning. It was also discovered that NGOs are good at mobilizing communities and also have the capacity to impart skills to the communities. Participants from NGOs confirmed that learning occurred through Masibambane programme even though some felt that the needs of the NGOs were not adequately addressed.
447

An Economic Appraisal of Reuse Concepts in Regional Water Supply Planning

Narayanan, Rangesan 01 May 1976 (has links)
Using a conceptual model of a water supply firm, the necessary conditions for production and market efficiency are derived when renovated wastewater is considered as a potential water resource. The nature and extent of the supply augmentation due to recycled reuse is demonstrated using classical optimization techniques. Three stages of short-run supply corresponding to no recycling, partial recycled reuse and complete recycling of all reclaimable water are identified through appropriate Lagrangian Multipliers as well as graphical techniques. A mathematical programming model is structured to determine the optimal water resource allocation and pricing policy for Salt Lake County. By maximizing the sum of consumer and producer surplus (the difference between total willingness-to-pay and total cost) economically efficient equilibria are derived. The feasibility of recycled reuse for municipal purposes is examined in a planning context. The impact of higher water quality discharge standards on the attractiveness of water recycling option is studied. To ensure social acceptability of renovated wastewater for culinary purposes, blending restrictions are imposed, which stipulate that the amount of water for reuse be less than a fixed percentage of the water from other sources. The effect of such a constraint on the prices and water allocation are delineated. The hydrologic uncertainty in water supply is treated using stochastic programming techniques. Application of the concepts of single and joint chance-constrained programming are illustrated. The resulting changes in pricing and allocation policies are discussed.
448

Substainable water resource management in Singapore

Tang, Sidney. January 2001 (has links) (PDF)
Bibliography: leaves 61-64. This thesis reviews the sustainability of water resource management in Singapore and adequacy of the water conservation efforts put up by its government, population and industries. The write-up deliberates on the various trans-national water issues faced by the small Republic, interactions within its water sector and with the rest of the economy, management of its water supply and demand, as well as the various problems and challenges confronted by the country. This study is intended to highlight the relative wisdom of reducing water demand over pursuing supply solutions.
449

Probabilistic microbial risk assessment and management implications for urban water supply systems

Signor, Ryan S., Civil & Environmental Engineering, Faculty of Engineering, UNSW January 2007 (has links)
Urban drinking-water supplies are still implicated as pathways for the transmission of waterborne disease. A move toward risk informed, proactive water system management has occurred over the past decade and is advocated in current international drinking water guidelines. Quantitative Microbial Risk Assessment (QMRA) is a tool with potential for aiding health risk management; however the refinement of scientific based practical methods to support that philosophy still requires development. This thesis focused on the water utility, its responsibility to manage microbial water safety, and how probabilistic QMRA may aid in developing management strategies. A framework for waterborne disease risk assessment from urban supply systems was derived and tested on an Australian case study. The main premise was that, in order for risk assessment outcomes to inform the management process, the steps should incorporate the concepts of risk variability, the explicit event conditions that can drive it, and that examination of QMRA sensitivity to various risk scenarios/model uncertainties is undertaken. The identified management uses were: (i) prioritising for attention issues hampering the system's ability to meet or the assessor's ability to interpret against (e.g. knowledge gaps about the system), a water quality health target; and (ii) identifying potential strategies or control points for addressing those issues. Additionally, rarely occurring, high impact, adverse fluctuations in treated water quality (and consumer infection risks), especially from source water contaminant "peaks", are highly, nearly totally, influential over the extent of risks averaged over longer, say annual, periods. As such, a case is made calling for widespread adoption of health targets that refer to tolerable consumer risks per exposure, rather than or as well as the current common practice of expressing targets in terms of risks from exposure over a year or lifetime. Doing so may provide incentive and opportunities for improved management, and the future derivation of specific microbial treatment or treated water quality targets, with a view toward protecting the community from extreme high risk periods associated with disease outbreaks.
450

Water as a Public Good in Indonesia: An evaluation of water supply service performance in an Indonesian water supply enterprise as a means to address social and environmental justice concerns

Wijaya, Andy Fefta, wija0002@flinders.edu.au January 2006 (has links)
A water supply service can be seen as a public or private good, but this thesis makes the argument that water is vital for society and so to ensure accountability it is important that water governance includes citizens' participation for social and environmental justice concerns. Public goods are generally defined as goods and services that are provided by 'means of public policy' (Lane, 1993, p. 21), or 'collective political choice' (Stretton & Orchard, 1994, p. 54) rather than by means of an individual market mechanism in which private goods are usually provided. This thesis addresses the function of water as a public good. If social and environmental goals of water use are ignored, the implications can be detrimental particularly for the poorest members of society. An organization's goal effectiveness is usually related to its success in achieving desired outcomes of the organization's goals through a systemic management interaction across organizational aspects at the input, process, output, and outcome/impact stages. This thesis argues an evaluation model of performance measurement can be developed to reflect the characteristics of a public good for a water supply utility, and this model of performance measurement can assist in addressing issues of social and environmental justice. Harris et al argue that better governance can only be achieved by working for democracy in multiple arenas (Harriss, Stokke, & Tornquist, 2004, pp. 7-8). This study considers multidimensional performance measures taking on board the values of many stakeholders with different backgrounds. It 'unfolds' and 'sweeps in' in many dimensions in an attempt at systemic representation (Ulrich, 1983, p. 169). McIntyre- Mills states that 'service need to reflect the values of the users and for this to occur the users need to participate in and decide on policy design and governance' (McIntyre-Mills, 2003, p. 14). Performance measurement systems can be used to detect a gap between services supplied by providers and various needs demanded by stakeholders. The thesis develops an outcome performance measurement model for evaluating social equity and environmental justice concerns. It draws on and adapts four performance measurement models of the International Water Association, World Bank, Indonesian Home Affairs Department and Indonesian Water Supply Enterprise Association. A complementary combined method was developed that addresses qualitative and quantitative governance concerns as they perform to water supply performance problems. Three research methods were used, namely the case study, survey and focus group discussion for collecting qualitative and quantitative data from the three governance sectors. These were triangulated. Five research tools in the case study method were used for collecting information from stakeholders in the three governance sectors including interview, personal communication or email, document analysis, direct observation and documentation. The survey was used to investigate 431 respondents from three case study locations in Cinusa1 city, and the two focus groups were conducted in the city's water supply company management for discussing problems of water supply performance as summarized from the survey. The locus of this study was concentrated in the Cinusa city jurisdiction area, and the focus was the performance problem of the water supply company in Cinusa during 2001-2004. However, a comparative study of water supply performance nationally and internationally is presented for analyzing relative performance gaps.This research evaluates interconnections among cost inefficiency, tariff escalation and other non-financial performances: water supply quantity, quality, continuity and pressure. Inefficient costs because of corrupt, collusive and nepotistic practices in this Indonesian water supply company implicate cost burdens in the company and prevent this water local public enterprise perform its social and environmental missions. The Cinusa local government as the owner of this local public enterprise and the Cinusa local parliament hold a monopoly power in some important decisions related to this local public enterprise, including tariff policy, senior management positions and the total amount of profit share paid to the local government. Such customers from lower income household instead of being subsidized as specified in the national regulation are paying at a profitable tariff and subsidizing this enterprise's inefficiency and the government's locally generated revenue. The inefficiency alongside the profit sharing policy also weakens this enterprise's capacity to invest and improve its service performances. Improving the service performance is essential for current and potential customers and could also benefit the society economically, socially and environmentally, besides being of economic benefit to the enterprise itself. Securing public health concerns and groundwater preservations can be conducted by improving the accessibility, the availability and the reliability of water quality, quantity, pressure and continuity. This research presents an evaluation model for improving the accountability of water supply by means of performance management tool and it makes policy recommendations.

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