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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

Water quality information system for integrated water resource management

Tukker, Mary Jean 12 1900 (has links)
Thesis (MEng)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: The processes of monitoring, modelling and managing the water quality of a catchmerit system including all its unique complexities and interrelationships requires an innovative tool or set of tools to help water managers with their decision making. Numerous methods and tools have been developed to analyse and model the real world. However, many of these tools require a fair degree of technical expertise and training to operate correctly and their output may have to be translated or converted to meaningful information for decision-making using a further set of analytical and graphical display tools. A more appropriate technique for management would be to combine all these functions into a single system. The objective of this research was to develop one such tool, an integrated water quality information system (WQIS). A review of the literature revealed that there has been extensive research and development of tools for the management of individual aspects of water resource distribution, augmentation and quality. However, these tools have rarely been integrated into a comprehensive information system offering decision support to a wide variety of river users and managers. Many of the literature sources also noted that a process of interactive development and integration (i.e. including the intended users in the decision of which components to include, the interface design and the graphical display and output) was vital to ensuring the information system becomes an integral part of the users routine work and decision-making. The WQIS was developed using the recommendations from numerous knowledgeable persons in response to questionnaires, interviews and a prototype demonstration. It includes the results of hydrodynamic river and reservoir simulations and the ability to perform operational river scenario testing. However, the development process is continual and always evolving based on the current or local requirements of water managers. These further developments and research needs are discussed in more detail in the conclusion. / AFRIKAANSE OPSOMMING: Die proses om die waterkwaliteit van 'n opvanggebied, met al die unieke kompleksiteite en onderlinge verhoudings van so 'n stelsel te monitor, modelleer en bestuur, vereis 'n innoverende instrument om waterbestuurders te ondersteun in hul besluitnemings. Talle instrumente en metodes vir die ontleding en modellering van die werklikheid is reeds ontwikkel. Die gebruik van hierdie instrumente vereis gewoonlik 'n redelike mate van tegniese kundigheid en opleiding. Dit mag verder nodig wees om die uitvoer van sulke instrumente te vertaal en/of om te skakel na betekenisvolle inligting vir besluitneming deur die gebruik van bykomende analitiese en grafiese vertoon instrumente. 'n Meer toepaslike bestuurstegniek sou wees om al die funksies in 'n enkele stelsel te kombineer. Die doel van hierdie navorsing was om een so 'n instrument, naamlik 'n geïntegreerde waterkwaliteit inligtingstelsel (WQIS), te ontwikkel. 'n Hersiening van bestaande literatuur het getoon dat daar omvattende navorsing en ontwikkeling van instrumente gedoen is vir die bestuur van individuele aspekte van waterbronverspreiding, waterbronaanvulling en waterkwaliteit. Integrasie van hierdie instrumente, in 'n uitgebreide stelsel wat besluitnemingsondersteuning aan 'n verskeidenheid riviergebruikers en bestuurders bied, kom egter selde voor. Verskeie literatuurbronne het ook aangedui dat 'n proses van interaktiewe ontwikkeling en integrasie (m.a.w. in agname van die voorgenome gebruikers se behoeftes in die kense van komponente, die gebruiker raakvlak ontwerp en grafiese vertoon instrumente en uitvoer) noodsaaklik is om te verseker dat die inigtingstelsel 'n integrale deel word van die gebruiker se daaglikse roetine en besluitnemingsproses. Die WQIS is ontwikkel deur gebruikmaking van die insette en aanbevelings van verskeie kenners in reaksie op vraelyste, onderhoude en 'n demonstrasie van 'n prototype. Dit sluit in die resultate van hidro-dinamiese rivier en dam simulasies en die vermoë om operasionele rivier scenario ontledings uit te voer. Die ontwikkeling is egter 'n deurlopende proses, gebaseer op huidige of plaaslike behoeftes van waterbestuurders. Hierdie verdere ontwikkelings- en navorsingsbehoeftes word meer breedvoerig in die gevolgtrekkings bespreek.
72

The dynamics of stakeholder participation in water resources management in Zimbabwe: a case study of the agricultural sector.

Kujinga, Krasposy January 2004 (has links)
The major aim of this study was to analyse the dynamics of stakeholder participation in the agricultural sector during the first five years of the water reform process in Zimbabwe. Specific reference is made to water allocation, conflict management and the payment of costs related to water use. Stakeholders investigated are those in communal smallholder irrigation schemes, large-scale commercial white and black farms and those resettled under the government's fast track land resettlement programme. The study was undertaken in the Middle Manyame Subcatchment area, which falls under the Manyame Catchment area.
73

The application of water pinch analysis at AECI bioproducts.

Schneider, Janos Pal Zsigmond. January 2002 (has links)
AECI Bioproducts (Bioproducts) is part of an industrial complex located at Umbogintwini, approximately 26 km south of Durban, Kwazulu-Natal. This system was selected for water pinch investigation, as it is one of the major users of freshwater on the complex and hence discharges a related quantity of wastewater, amounting to approximately 400 ML per annum. Bioproducts is a manufacturer of l-lysine, which is an animal feed additive. Water stream flowrate and purity data, as well as operating cost information, were obtained from plant records at AECI Bioproducts. Limiting flowrate and purity conditions for the water-using operations were established from a mass balance over the entire system using the Linnhoff-March software, WaterTracker. Subject to the specified constraints and operating costs, the problem was to determine the design of the water-using subsystem. No treatment plants were included in the study, as none exist at the facility. Three scenarios were investigated, which examined the operating variability of one of the evaporators on the site (the AS evaporator), which produces a condensate source of variable purity. The operating cost target and network design for each scenario was determined using the Linnhoff-March software, WaterPinch. Alterations from current operating practice were identified and associated savings (water-using network operating cost and freshwater flowrate) were highlighted. A robust optimal design was identified, with a recycle, which was consistent for all scenarios investigated. The degree of reuse of the AS evaporator condensate source was determined to be dependent on the purity of the source. The limiting constraint was identified at the sea pipeline, for suspended solids (SS): a prohibitively low discharge concentration constraint was identified as posing the major obstacle for saving. The potential for saving was investigated by incrementing the SS concentration constraint and subsequently the free and saline ammonia (FSA) constraint and allowing for the broth effluent to be discharged via the sea pipeline (which was previously disallowed by an effluent exemption). Although relatively small savings were identified through process integration (from 0.61% to 1.56% of the water-using network operating cost), the analysis identified a potential saving of over 70% of the water-using network operating cost, with relaxation of the sea pipeline SS and FSA constraint. / Theses (M.Sc.)-University of Natal, Durban, 2002.
74

Water management at a base metals refinery

Osman, Ayesha January 2016 (has links)
MSc Dissertation Submitted to School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, South Africa 12 August 2016 / Most mineral processing plants have high water requirements for their operational activities. These plants often function in an environment where water is becoming increasingly scarce. An increase in population will result in an increased demand for water, potentially beyond the limits of supply, and hence increased competition for the resource. In South Africa, Gauteng and the North West Province are likely to be first to experience a shortage of potable water. The key to a sustainable future lies in understanding and utilising resources more efficiently. This holds especially for industries who seek to minimise water usage through better management of resources. The two tools used in this study are the Water Accounting Framework (WAF) and Water Footprinting (WF) method. This research assisted a refinery in the North West Province understand its water usage and move towards operating in a more sustainable manner. Site water management was improved and the objective of this research fulfilled by: (i) Surveying the potable water and the storm water systems with a view to assessing the current water accountability and determining methods to improve accountability; (ii) Determining the water balance for the site and presenting it in the form of a water balance sheet; (iii) Reporting water usage in accordance with the Minerals Council of Australia’s “Water Accounting Framework for the Minerals Industry”; (iv) Calculating the water footprints of the refinery; and (v) Evaluating the water usage at the refinery and identifying ways in which water savings could be achieved. It was seen that the biggest consumer of water was the boilers and utilities section and the biggest loss of water was through evaporation. The refinery potable water requirement (2 280 m3/y) amounted to 0.16% of the daily water use for the Bojanala Platinum District. Four reports (outputs) were generated using the WAF. The four reports generated provide a good indication of the movement of water into, out of and during a process. WFs were calculated for the process. The blue WF was calculated to be 832 363 m3 and the green WF was calculated to be 261 970 m3. The product WF was 43.9 m3/t of base metal produced. There was no grey WF as the site does not discharge polluted water. This research provided an opportunity for the refinery to improve water efficiency onsite as well as improve reporting standards. Water usage was reported using global reporting tools to set a benchmark for the base metals industry. / MT2017
75

Advective water quality model for urban watercourses.

Furumele, Musa Stefane January 1991 (has links)
A project report submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineerrng, / As has happened throughout the world. environmental and water quality problems related to developing urban and industrial areas and associated accumulation of waste in built-up areas were the main factors in contributing to sanitary awareness in South Africa. The dwindling water resources and persistent deterioration of water quality, more severely in urban areas, necessitates the review the current practice of storm water management in South Africa. Reliable stormwater drainage models evaluating both the water quantity and quality could be essential in confronting the prevailing pollution problems. The objective of this project was conceived to be the development of a system for the simulation of water quality in urban watercourses, A personal computer compatible model for joint transportation of hydrograph and pollutographs in open channels was developed. The model comprises an operational data handling facility, a user friendly and interactive interface. The study revealed that: Urban and Industrial development results in complication of the urban water system. • Single objectivity approaches in management of urban watercourses are outdated . .. The proposed model is capable of simultaneously routing flood and pollutant condiment waves in open channels. Understanding of aspects of the water quality in urban watercourse can be greatly enhanced by the proposed model. The following recommendations were henceforth made: • Detailed study of the nature. quantity and sources of pollutants in the urban water system. .. Sophisticated (dynamic wave. supercritical flow, complicated ..................... hydrodynamic model snould be considered, • Biological and, chemical process in the urban watercourse be incorporated. • Linking of the water quality model to the storm water drainage model, / Andrew Chakane 2018
76

Water, Economics, and Policy in Developing Countries

Plous, Evan Michael January 2016 (has links)
Water is essential for life, and access to sources of safe water and sanitation facilities is a first-order concern for economic welfare and general well-being. While the majority of residents in developing countries have access to improved water and sanitation services, many parts of the developing world lag significantly behind in this vital infrastructure. This dissertation studies policies aimed at increasing access, quality, and efficiency of improved water and sanitation (WS) services in developing countries. In the following three chapters, I focus on non-technological methods for improving service by eliminating the economic, political, and institutional barriers to safe water and sanitation provision. Chapter 1, “The Buck Stops Where? Federalism and Investment in the Brazilian Water and Sanitation Sector”, shows how weak institutions can undermine public goods service when multiple levels of government share responsibility of provision. In particular, I study how legal ambiguities regarding degrees of governmental authority can lead to systematic underinvestment in public utilities. I examine the Brazilian water and sanitation (WS) sector, which presents an natural experiment of shared provision between state and municipality entities. I look at a legal reform that clarified the relationship between municipalities and states in a quasi-experimental, difference-in-differences framework, using an administrative, municipality-level panel dataset from 2001-2012. I find that when expropriation risk by state companies diminished - self-run municipalities almost doubled their WS network investment. This increase in investment led to a significant increase in access to the WS system in these municipalities. The analysis provides strong evidence that reforms that strengthen residual control rights and eliminate the threat of intra-governmental expropriation can lead to large increases in public goods investment. Chapter 2, “The Role of Basic Sanitation Plans on Service Provision: Evidence from Brazil”, investigates non-technological methods of increasing access to improved water and sanitation (WS) in developing countries. In particular, it presents evidence of the efficiency gains that can be achieved in municipal water provision through the act of formulating and carrying out basic sanitation plans. I exploit the staggered roll-out in implementation of basic sanitation plans throughout municipalities in southern Brazil from 2007-2013. I find that, in the three years after the enactment of sanitation plans, municipalities increased the efficiency of their respective water systems through the tightening up of “leakages" in the system, both in terms of water distribution and bill payment. However, I find no significant increases in the degree of individual access to the systems, suggesting that in the relatively short-run, providers focus on improving the existing system as opposed to building out new infrastructure. Chapter 3, “(Not So) Gently Down The Stream: River Pollution and Health in Indonesia”, addresses the fact that waterborne diseases are the leading cause of mortality in developing countries. We emphasize a previously ignored cause of diarrhea - upstream river bathing. Using newly constructed data on upstream-downstream hydrological linkages along with village census panel data in Indonesia, we find that upstream river bathing can explain as many as 7.5% of all diarrheal deaths. Our results, which are net of avoidance behavior, show no effect of trash disposal on diarrheal infections. Furthermore we find that individuals engage in avoidance behavior in response to trash disposal (visible pollutants) but not river bathing (invisible pollutants). We conduct policy simulations to show that targeting upstream individuals could generate substantial environmental and health savings relative to targeting downstream individuals. This provides a potential road map for low- and middle-income countries with limited resources for enforcement of water pollution.
77

Seleção de ferramentas de gestão interativas para o setor de aquisição e suprimentos na cadeia produtiva de Engeneering, Procurement and Construction (EPC) no Rio de Janeiro: um estudo multi casos

Carnevale, Glícia Curti Sant'Anna 18 January 2013 (has links)
Submitted by Joana Azevedo (joanad@id.uff.br) on 2017-08-08T14:02:47Z No. of bitstreams: 1 Dissert GLICIA CURTI SANT'ANNA CARNEVALE.pdf: 1239350 bytes, checksum: 4942bb1b5b80e4e328c92fa6b41d6997 (MD5) / Approved for entry into archive by Biblioteca da Escola de Engenharia (bee@ndc.uff.br) on 2017-08-29T14:19:41Z (GMT) No. of bitstreams: 1 Dissert GLICIA CURTI SANT'ANNA CARNEVALE.pdf: 1239350 bytes, checksum: 4942bb1b5b80e4e328c92fa6b41d6997 (MD5) / Made available in DSpace on 2017-08-29T14:19:41Z (GMT). No. of bitstreams: 1 Dissert GLICIA CURTI SANT'ANNA CARNEVALE.pdf: 1239350 bytes, checksum: 4942bb1b5b80e4e328c92fa6b41d6997 (MD5) Previous issue date: 2013-01-18 / O estudo tem por objetivo descrever, analisar e propor um conjunto de tecnologias aplicáveis ao auxílio da gestão da aquisição, do diligenciamento, da inspeção e da contratação de itens de suprimento que compõem um Empreendimento Complexo para, assim, permitir que as empresas EPCistas no Rio de Janeiro tenham ganhos de produtividade, sem perda da qualidade inerente ao processo. Os conceitos-chave que permeiam o trabalho giram em torno da tecnologia envolvida para otimizar a gestão de suprimentos de empresas que compõem a cadeia produtiva EPC. De modo a permitir uma melhor leitura do comportamento dos EPCistas no Rio de Janeiro e, consequentemente identificar as melhores práticas e ferramentas interativas mais aplicáveis a esse nicho, foi realizado um estudo aprofundado dos principais stakeholders que influenciam ou são influenciados por essa cadeia, tais como: visão do contratante, do fornecedor, do parceiro e de instituições de classe que atuam promovendo boas práticas de gestão do setor. O estudo, realizado através de entrevistas direcionadas aos principais stakeholders dos EPCistas, trás elementos que fundamentam a necessidade de implementação de soluções tecnológicas mais adequadas à evolução pela qual essa cadeia passará, influenciada especialmente pelas descobertas do Pré-Sal. / The present study aims to describe, analyze and propose a set of technologies applicable to aid the management of the acquisition, the expediting, inspection and contracting supply items that compose a complex undertaking to thereby allow companies in EPCistas Rio de Janeiro have productivity gains without loss of quality inherent in the process. The key concepts that permeate the work revolve around the technology involved to optimize the supply management of companies that make up the supply chain EPC. To enable a better reading of the behavior of EPCistas in Rio de Janeiro and thus identify best practices and interactive tools most applicable to that niche, we performed a detailed study of the major stakeholders that influence or are influenced by the chain, such as: Vision of the contractor, supplier, partner and working-class institutions by promoting good management practices in the industry. The study, conducted through interviews of key stakeholders aimed to EPCistas, behind elements that underlie the need to implement technological solutions to the most appropriate evolution through which the chain will, especially influenced by the pre-salt discoveries.
78

Water supply management in an urban utility : A prototype decision support framework

Kizito, Frank January 2009 (has links)
In this study, four real-life problem situations were used to explore the challenges of developing and implementing decision support tools for planning and management within an urban water utility. The study sought to explore how the degree of adoption of formal decision support tools in practice, generally perceived to be low, could be improved. In the study, an Action Research (AR) approach was used. AR is an inquiry process that involves partnership between researchers and practitioners for the purpose of addressing a real-life problem issue, while simultaneously generating scientific knowledge. Unlike other research methods where the researcher seeks to study organizational phenomena but not to change them, the action researcher attempts to create organizational change and simultaneously to study the process. During the study, a number of prototype data management tools were developed. GIS-based spatial analysis and visualisation tools were extensively used to inform and enhance the processes of participatory problem identification and structuring, while a number of modelling tools were applied in the generation and evaluation of alternative solutions. As an outcome of the study, a prototype framework for the application of decision support tools within an urban water supply planning and management context was proposed. The study highlighted the challenges of embedding formal decision support processes within existing work systems in organizations, and recommendations were made on how best to achieve this. The AR approach was found to be useful in bridging the gap between academic research and technological practice, supporting the development of computerised planning and decision support tools of practical benefit to organizations. / QC 20100723
79

Hydrological modelling applications for water resources management in the Mkomazi Catchment.

Taylor, Valerie. January 2001 (has links)
Predictions that water shortages will constrain economic growth in South Africa by 2025 have led to increased concerns among water resource managers that there is a need for comprehensive water management strategies. To this extent the new South African Water Act requires that water resource allocation be approached in a more equitable and conservative way than in the past in order to sustain water resources for catchment development. This includes protection of the water resource base by the setting aside of a health Reserve for basic human needs and for the ecological functioning of rivers. At a time when water resource management is shifting from the practice of large dam construction to reconciling water demand with water supply in more holistic strategies, the Mkomazi Catchment in KwaZulu-Natal provides an opportunity to investigate some of the major issues that dominate contemporary water resource management. Presently (2001), there are no impoundments on the Mkomazi River and the catchment is generally underdeveloped. These factors have provided the impetus for the Department of Water Affairs and Forestry's proposed inter-basin transfer scheme to use the surplus flow in the Mkomazi Catchment to augment the water resources of the neighbouring Mgeni system. Impact-of-Iand-use and development scenario studies, using the ACRU agrohydrological modelling system, were performed to simulate the impacts of (a) baseline land cover, (b) present land use, (c) the first phase of the Mkomazi-Mgeni Transfer Scheme and (d) potential climate change on the hydrological dynamics of the Mkomazi Catchment. The results indicate that the change from baseline land cover conditions to present land use conditions has little impact on the annual water resources of the Mkomazi River. This is especially so in the upper catchment where there is little anthropogenic development and from where the planned inter-basin transfer will be made from the proposed Smithfield Dam. Although the impacts of commercial forestry and irrigation in the middle and lower catchment impose local stress on streamflow generation, they do not detract substantially from the main downstream flows. Evaluation of the impacts of the proposed Smithfield Dam on annual streamflow generation revealed that there is more than sufficient water in the upper Mkomazi Catchment to sustain the inter-basin transfer under present climatic conditions. However, under potential climate change the median annual Mkomazi streamflows at the estuary could be reduced by 46% if the dam was constructed, compared with a 22% reduction under present climatic conditions. The impacts of catchment development on the seasonal low flows within the Mkomazi Catchment indicated that those areas which are already heavily utilised by afforestation and, particularly, by irrigated land use are unlikely to be able to support any further large scale commercial agricultural development, even under present climatic conditions. Water management strategies for the Mgeni system will impact on potential water allocation within the Mkomazi Catchment. The results of the impacts studies were used to assess the water demand of the major water-use sectors and the availability of streamflows for further allocation was assessed. Present total annual water demands of Mkomazi streamflows is minimal. Even allowing for the environmental demand in the Mkomazi Catchment, as identified by the Building Block Methodology during an instream flow requirements workshop, as well as the first phase of the inter-basin transfer, there would be surpluses of 66%, 43%, 42% and 45% of streamflows, respectively, at the four instream flow requirement sites on the Mkomazi River. The results of the Mkomazi instream flow requirements workshop were revisited to assess the achievability of the recommended flows within the ACRU generated daily time series of streamflows for each of the scenarios simulated, at the each of the four instream flow requirement sites on the Mkomazi River. The results confirmed the need to ascertain the Mkomazi River's natural flow variability, and to assess how much alteration is likely under development of the Mkomazi Catchment. The Indicators of Hydrologic Alteration and Range of Variability Approach methodologies were used to determine which components of the streamflow regime would be most impacted by the inter-basin transfer. Hypothetical, yet realistic, upper and lower management target thresholds were applied to determine the range of variation experienced by the streamflow regime of the Mkomazi, under both pre- and post-dam construction conditions, and to evaluate a preliminary assessment of the characteristics of the streamflow regime required to meet environmental sustainability. The issues raised by potentially conflicting water uses within catchments in South Africa have indicated that any approach to address the increasing complexity of water resource problems, and the management thereof, requires effective hydrological modelling. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2001.
80

The dynamics of stakeholder participation in water resources management in Zimbabwe: a case study of the agricultural sector.

Kujinga, Krasposy January 2004 (has links)
The major aim of this study was to analyse the dynamics of stakeholder participation in the agricultural sector during the first five years of the water reform process in Zimbabwe. Specific reference is made to water allocation, conflict management and the payment of costs related to water use. Stakeholders investigated are those in communal smallholder irrigation schemes, large-scale commercial white and black farms and those resettled under the government's fast track land resettlement programme. The study was undertaken in the Middle Manyame Subcatchment area, which falls under the Manyame Catchment area.

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