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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.
111

Modeling of Hydrologic Processes and Water Salvage Procedures in Semiarid Regions

Resnick, S. D. 12 1900 (has links)
Partial Technical Completion Report, Office of Water Resources Research, Project A-020-ARIZ / Grant Agreement No. 14-31-0001-3203 / Period of Investigation: 7/69-6/71 / Potential uses or reuses of salvageable waters in the Tucson region were examined, and costs and benefits related to such uses were evaluated. The quality of salvageable waters as determined in exploratory sampling was compared with water quality standards and criteria appropriate for agricultural, recreational and selected industrial uses. A tableau was then constructed which showed the type and estimated cost of conventional water treatment that would be required for each source-to-use combination. Finally, an estimate was made of unit net benefits to be anticipated from salvageable water input to these uses, and the net benefits were applied in several test calculations to illustrate mixed allocations of the various salvaged waters to the selected uses.
112

An environmental life cycle assessment of the provision of recycled water in Durban.

Pillay, Sarushen Dhanapalan. January 2006 (has links)
This dissertation investigated the questions of sustainable development, in the context of water and sanitation provision, for the eThekwini Municipality. The Durban Water Recycling (DWR) plant, run by Veolia Water, was initially the focus of this investigation. The use of recycled water in Durban has freed potable water supplies for a potential 200 000 new consumers. Industry also benefits as the recycled water is supplied at a lower cost. In order to create a holistic picture of the effect of water recycling, a network incorporating the abstraction, use, re-use and disposal of water in the South Durban Region was investigated. This water supply network was identified consisting of the following units: Inanda Dam, Wiggins Waterworks, the pumping and reticulation network, Durban Southern Wastewater Treatment Works, Durban Water Recycling and the Durban Southern Deep Sea Outfall. For the environmental analysis the Life Cycle Assessment (LCA) tool was chosen. Life cycle assessment is a systematic way to evaluate the environmental impacts of products or processes by following a scientific methodology in which the impacts are quantified. LCA provides objective answers to environmental questions while suggesting more sustainable forms of production and consumption. It is the only tool which has a cradle-to-grave approach and by this it avoids positive ratings for measurements which only consist in the shifting of burdens. The objective of this LCA was twofold. The first was to quantify and evaluate the environmental performance of relevant processes and so help decision makers choose amongst options. The second objective was to provide a basis for assessing potential improvements in the environmental performance of the system. Once these areas and the contributors to the high burdens were identified, improvement options were investigated. One of the key outcomes of this analysis was the development of an electricity index as an indicator of environmental performance for water and wastewater systems. The GaBi 3 software package, which uses the CML (Centre for Environmental Science, University of Leiden, The Netherlands) LCA methodology, was used to compile environmental impact scores for each impact category. For the non standard systems such as Inanda Dam and the Durban Southern Deep Sea Outfall a new way of assessing the impacts was developed. There is an emerging trend to combine the LCA methodology with social issues so as to improve the decision making capability. The social analysis was carried out using an LCA type methodology. The impact categories selected were; job creation and health and health risks. During the course of the study the issue of land displacement arose when investigating the social issues surrounding the construction of a dam. This was then incorporated into the entire study. The system was broken up into sub-systems which were studied separately and then combined to create a holistic picture. Each sub-system was further divided into three stages for analysis; the construction, operation and decommissioning. This method of analysing the system allows for the detailed description of individual process units with the highest social and environmental burden. For example it was identified that the operation of the activated sludge systems at the wastewater treatment works had an environmental burden due to the electricity consumption during this stage. For the impact category of global warming it was discovered that 40% of the total environmental impact of the system could be attributed to the secondary treatment stage at the wastewater works. The construction of the dam had the largest social burden due to the displacement of the communities living in the dam area. The final part of the study was a scenario analysis. The aim of this analysis was to develop a sustainability framework for municipalities seeking to expand their provision of water and sanitation services. Different scenarios for increasing the water supply of a municipality were considered. The environmental impact of each scenario was also investigated. In this stage various options were considered to see how changes in the system affected the environmental profile. Improvements using new, modified or alternate technologies were suggested and their effects calculated. An operating procedure, for the current system, with the lowest environmental impact was also suggested. The results of this research will prove valuable to designers and planners looking to expand existing water supply networks in a sustainable manner. A sustainability framework was developed to complement the existing DWAF framework for municipalities expanding their provision of water and sanitation services. The key findings of this study were: • The quantification of the environmental burdens for the supply of water and sanitation in the eThekwini Municipality first for the individual units then for the system. • An improvement analysis which suggested ways of reducing the environmental burdens of the existing system. • The development of a sustainability framework for a municipality to increase its water and sanitation service levels. • The incorporation of social indicators into the LCA methodology. • The development of a technique that could be incorporated into the LCA methodology, for assessing the toxicity of complex effluents. • The development of a method of evaluating the environmental performance of a water and sanitation system using an electricity index. The thesis provides a holistic view of the abstraction, use, re-use and disposal of water in the eThekwini Municipality and provides a guideline for decision makers when assessing options for expansion or improvement in water supply networks. / Thesis (Ph.D. Eng.)-University of KwaZulu-Natal, Durban. 2006.
113

Technical feasibility of dyeing nylon carpets in a reconstituted dyebath

Tata, Adi Shapur 12 1900 (has links)
No description available.
114

Heavy metals uptake by wheat under two transpiration rates

Salah, Sharif Ali. January 2001 (has links)
The present project aimed at measuring plant heavy metal uptake as a function of transpiration rates and dissolved heavy metal level in the soil solution. Two experiment was conducted separately in two season (Spring and Fall 2000). In these two experiments, young wheat plants ( Triticum aestivum) were irrigated with nine different solutions containing Cd and Zn. The study was conducted in two chambers where relative humidity was controlled to obtain two different levels of transpiration rates. Each control chambers contained 27 pots filled with sand and seeded with wheat plants, each nine triplicated pots receiving a different treatment: three Cd treatments with levels of 0.01, 0.10, and 0.50 mg/L; one Zn treatment with level of 25mg/L and four treatment combinations of Cd/Zn with levels of 0.01 Cd/25Zn, 0.10Cd/25ZN, 0.50Cd/25Zn and 0.50Cd/50Zn mg/L. The transpiration rate of the plants was monitored over a period of 30 days, measured from the emergence of the plants by weighing the pots daily. On day 15 and 30, three plants were removed from each pot, to weigh their dry matter production and to analyze their heavy metal uptake. (Abstract shortened by UMI.)
115

Recycling and reusing a restaurant's waste : creating a sustainable small-scale urban farm

Conklin, Lorraine C. January 2006 (has links)
Urban sprawl, global warming and overused landfills are conditions around the world today, and while people are concerned about these issues they have few practical solutions to them. This creative project seeks to devise a way for a specific sector of business (restaurants), to have a practical way to help reduce global warming and waste while utilizing unused or under-used land in urban areas. While life cycle models are available that address such issues as these, very few case examples are actually in use in this country. Based on existing life cycle models, this project will seek to reuse the wastes from a restaurant and recycle them into a garden/greenhouse (called an urban farm throughout this paper) which will produce food for the restaurant. The three main waste categories from the restaurant to be looked at are the organic kitchen food wastes, water and the heat that is always being expelled from the kitchen while it is operation. Additional ways to make a restaurant more sustainable will also be given. This project will show what the benefits are when a sustainable system is in operation. / Department of Landscape Architecture
116

Fate and transport of selected endocrine disrupting chemicals in recycled water through a tropical soil

Mohanty, Sanjay K January 2006 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 131-144). / xiv, 144 leaves, bound ill. 29 cm
117

Fate and Transport of Selected Endocrine Disrupting Chemicals in Recycled Water Through a Tropical Soil

Mohanty, Sanjay K 08 1900 (has links)
Endocrine disrupting chemicals (EDCs) are a group of synthetic and natural chemicals that have the potential to mimic the hormone-like activities in the human body. This study was conducted to recognize whether recycled water (a source of EDCs) has the potential to contaminate the environment when such water is used for irrigation purposes. Batch sorption and miscible displacement experiments were conducted to elucidate the fate and transport of four EDCs including estrone, 17β estradiol, octylphenol and nonylphenol in a soil from Hawaii. The sorption capacity of the soil from two depths (2 ft as topsoil and 15 ft as saprolite) was estimated using recycled water and deionized water as the mobile phases. The transport parameters of these contaminants were obtained by using the inverse modeling approaches as provided in the HYDRUS 1D code. All four EDCs sorbed significantly on the soil. Octylphenol and Nonylphenol rapidly degraded during sorption. The Freundlich model was suitable to describe the sorption isotherm. The sorption nonlinearity was relatively higher for saprolite compared to topsoil. Both physical and chemical non-equilibrium processes were found to affect the mobility of the EDCs in the soil. The migration of EDCs in the soil was enhanced in recycled water due to the presence of dissolved organic carbon and elevated salt concentration. The ambient pH had little effect on sorption of EDCs on the soil from either depth.
118

Management and reuse of local water resources in residential developments in Adelaide /

Barton, Annette Unknown Date (has links)
This thesis reports on research undertaken into the integration of water reuse systems into medium to high density residential developments in the semi-arid climate environment of metropolitan Adelaide. The research has focused on maximising the reuse of local water resources for residential lifestyle purposes, through the incorporation of relatively simple water sensitive systems into subdivision type developments, where allotments are less than 500 sq.m. / The quantities and qualities of the local water resources- roof runoff, surface runoff and wastewater- are considered and a paradigm for their reuse presented in which each local water resource is linked with a residential use sector- in-house, ex-house and public space- in order to minimise treatment requirements. On the basis of this paradigm a water sensitive residential model (WSRM) is developed. This model constitutes a subdivision layout which incorporates reuse systems while endeavouring to keep water systems infrastructure to a minimum. / Following on from this, the feasibility of the WSRM has been investigated by applying it to three conventional residential developments within metropolitan Adelaide. These are located in the suburbs of Mawson Lakes, Taperoo and Aldinga Beach. The specific physical, topographic and hydrogeological conditions associated with each site have required a flexible approach to the application of the model; and while a unique arrangement has been found for each site, the basic elements of the WSRM have provided an underlying consistent theme across them all. / Water balance modelling using the WaterCress program has been undertaken for each site to gain an understanding of the level of 'water-self-sufficiency' that might be achieved with the WSRM. Modelling results have indicated that between 50-70% of domestic water needs can be satisfied using local water resources. / An economic assessment has been undertaken of the WSRM from the point of view of development costs. The water reuse systems have been designed and costed for each site. Development fees and charges have also been ascertained. This has enabled a comparison to be made with the costs and development charges of conventional type developments. It is concluded that while the costs of the WSRM developments were consistently greater than for conventional developments, the increasing need for developers to contribute to external works relating to infrastructure and the environment is altering the balance. When account is given to these external costs, 'reuse' developments are at least as equally viable as conventional developments. / The research has produced a practical model to build reuse systems into the fabric of the residential development, significantly reducing reliance on the mains water supply and creating more sustainable developments. It has also shown that the economics of such developments are changing for the better. / Adelaide, like other Australian capital cities, is presently beset with complex issues relating to water supply, wastewater and stormwater management. Better management and more sustainable use of the available water resources is needed; maximisation of water reuse and more efficient use of local water resources are becoming increasingly important. / The trend in Australia today is for medium to high density housing for inner city infill or redevelopment sites and for outer suburb greenfield sites. Water sensitive residential developments within Australia, which have incorporated water reuse, have generally been located in high rainfall areas (average rainfall above 1200mm/year) and/or where the average allotment size is greater than 600 sq.m.. Two exceptions to this are the New Haven village and Mawson Lakes developments in the greater Adelaide region, where the average rainfall is around 500mm/year. In these two cases, however, reuse accounts mainly for ex-house water uses; in-house water uses are essentially serviced by the mains supply with toilets being the only exception. / Thesis (PhD)--University of South Australia, 2005.
119

Sustainability and participation in the governing of water use: the case of water recycling

Stenekes, Nyree, Civil & Environmental Engineering, Faculty of Engineering, UNSW January 2006 (has links)
Urban water recycling has been promoted as one of several ways that water use efficiency could be improved in Australia???s cities, but few such schemes have been introduced. Many urban water-recycling schemes have been proposed, but often, these projects have been rejected because of community opposition. These difficulties suggest that recycling water is not just about having the right answer to any problem, but about the way in which the question is addressed. It is concerned with how practice is institutionalised; not just the rule making, but also the understandings and values that make the rule-making possible. In this thesis, the question of how the system of water governance could be strengthened to encourage sustainable water use through water recycling is examined. An analysis of experiences in three Australian case studies is conducted, in which recycled water was proposed for sustainability, to illuminate the way in which water use is institutionalised. Particular attention is given to the construction of meaning in relation to water use, by considering how water problems are framed and negotiated by different stakeholders and groups and the significance of the multiplicity of interpretive frameworks in use for the institutionalisation of practice. The analysis draws on institutional organisational theory and interpretive methods, which regard interpretation as one element (cognitive) in the stabilisation of social practice and closely linked to organisation (regulative) and values (normative). The study findings suggest meaning was a very important part of institutional change. Participants tended to construct policy issues as they became involved by drawing on different interpretive frameworks embodying different values and expectations. These interpretations reflected the organisational structuring of practice, such that the position/role in the organisational field reflected an actor???s interpretation of problems and/or solutions. Outcomes of the study suggest that institutionalising change in water management is problematic and depends on changes in the regulative, normative and cognitive dimensions of practice, as part of a continuous feedback loop between interpretation and practice. This view of change contrasts with existing research, which tends to see the problem in terms of influencing attitudes of specific groups and assumes preferences precede the action.
120

Management and reuse of local water resources in residential developments in Adelaide /

Barton, Annette Unknown Date (has links)
This thesis reports on research undertaken into the integration of water reuse systems into medium to high density residential developments in the semi-arid climate environment of metropolitan Adelaide. The research has focused on maximising the reuse of local water resources for residential lifestyle purposes, through the incorporation of relatively simple water sensitive systems into subdivision type developments, where allotments are less than 500 sq.m. / The quantities and qualities of the local water resources- roof runoff, surface runoff and wastewater- are considered and a paradigm for their reuse presented in which each local water resource is linked with a residential use sector- in-house, ex-house and public space- in order to minimise treatment requirements. On the basis of this paradigm a water sensitive residential model (WSRM) is developed. This model constitutes a subdivision layout which incorporates reuse systems while endeavouring to keep water systems infrastructure to a minimum. / Following on from this, the feasibility of the WSRM has been investigated by applying it to three conventional residential developments within metropolitan Adelaide. These are located in the suburbs of Mawson Lakes, Taperoo and Aldinga Beach. The specific physical, topographic and hydrogeological conditions associated with each site have required a flexible approach to the application of the model; and while a unique arrangement has been found for each site, the basic elements of the WSRM have provided an underlying consistent theme across them all. / Water balance modelling using the WaterCress program has been undertaken for each site to gain an understanding of the level of 'water-self-sufficiency' that might be achieved with the WSRM. Modelling results have indicated that between 50-70% of domestic water needs can be satisfied using local water resources. / An economic assessment has been undertaken of the WSRM from the point of view of development costs. The water reuse systems have been designed and costed for each site. Development fees and charges have also been ascertained. This has enabled a comparison to be made with the costs and development charges of conventional type developments. It is concluded that while the costs of the WSRM developments were consistently greater than for conventional developments, the increasing need for developers to contribute to external works relating to infrastructure and the environment is altering the balance. When account is given to these external costs, 'reuse' developments are at least as equally viable as conventional developments. / The research has produced a practical model to build reuse systems into the fabric of the residential development, significantly reducing reliance on the mains water supply and creating more sustainable developments. It has also shown that the economics of such developments are changing for the better. / Adelaide, like other Australian capital cities, is presently beset with complex issues relating to water supply, wastewater and stormwater management. Better management and more sustainable use of the available water resources is needed; maximisation of water reuse and more efficient use of local water resources are becoming increasingly important. / The trend in Australia today is for medium to high density housing for inner city infill or redevelopment sites and for outer suburb greenfield sites. Water sensitive residential developments within Australia, which have incorporated water reuse, have generally been located in high rainfall areas (average rainfall above 1200mm/year) and/or where the average allotment size is greater than 600 sq.m.. Two exceptions to this are the New Haven village and Mawson Lakes developments in the greater Adelaide region, where the average rainfall is around 500mm/year. In these two cases, however, reuse accounts mainly for ex-house water uses; in-house water uses are essentially serviced by the mains supply with toilets being the only exception. / Thesis (PhD)--University of South Australia, 2005.

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