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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.
1

Treatment of Graywater as a Suitable Solution to Save Water and Electricity for Iraq's Householders

Tawfiq, Wamid January 2011 (has links)
Conscious governments in the developing countries try to keep abreast of developments, by offering better services to their citizens; one of the important services is to preserve the natural water resources. Implementation of constructed wetlands part of sustainable water resource management and ecosystem is a new approach for water treatment and biological disposal of contaminants, therefore families can contribute to these treatments through the use this system in their houses.  In order to meet the demand of daily water consumption by separating greywater from wastewater and for its reuse after treatment constructed wetland systems are one of the successful ecological treatments to reduce the concentration of pollutants in greywater. In view of the acute water crisis supply in Iraq, the best solution found for covering the daily consumption of householders is to apply the constructed wetland for treatment of greywater. The implementation of green roofs technique is one of the best ways to intercept rainwater. Especially in Iraq, where this technique can be used to provide thermal insulation, and an appropriate environment, to use the roofs for sleeping at night in the summer season.
2

Health risk of growing and consuming vegetables using greywater for irrigation.

Jackson, Siobhan Ann Forbes. January 2010 (has links)
Two of the challenges facing Africa in the 21st Century are effective use of restricted water resources and ensuring food security especially for poor communities. In line with these aims, the eThekwini municipality has introduced a multi-tier system of water supply ranging from full pressure reticulated systems along with flush toilets to standpipes and dry toilet systems. In the latter case, it was soon recognized that the disposal of greywater presented a problem. Bearing in mind that South Africa is already a water scarce region, research was initiated into finding means of using this water as a resource rather than as a waste. Initial on-site trials using the greywater to irrigate crops proved popular and it was then regarded as necessary to test the possible health effects on the communities of such a system. A controlled field trial using pot plantings of a selected range of edible vegetables was initiated at the University of KwaZulu-Natal. Crops were tested both internally and externally for a range of indicator and potentially pathogenic organisms. Quantitative Microbial Risk Assessment (QMRA) techniques were used to assess the health risk to communities from growing and eating the greywater- irrigated vegetables. Although there was a health risk related to most of the activities, especially the handling of the greywater itself, the risks could be brought within the World Health Organisation guidelines of less than one case of disease per 10 000 people per year by the implementation of simple barrier interventions. The greywater irrigated crops themselves, did not present a statistically higher risk of infection than the crops irrigated with either hydroponic solution or tap water. These findings show the importance of applying QMRA to each case to determine health risk. This would allow the productive use of greywater and other water sources in the correct circumstances, thus providing food sustainability for people who currently do not have access to the levels of high purity water currently recommended for agriculture. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2010.
3

Creating Renewable Energy in a Residential High-Rise by Utilizing Greywater in a Hydropower Turbine

Santillan, Steven Gabriel, Santillan, Steven Gabriel January 2016 (has links)
Across the world, it is becoming increasingly obvious that we must change the way we live as human beings. Our population is over seven billion, and the natural world simply cannot sustain this large of a population unless we learn to live within its means. Buildings, the structures that house us and provide us with shelter every day, are responsible for nearly half of the energy consumption across the United States (eai.gov, 2008). As cities continue to grow and available land diminishes, buildings will only get taller and consume even more energy. This energy requires vast amounts of water, so as our population grows, we are using more energy and more water, two of the most critical components of human prosperity. Renewable and sustainable energy production is now more of a reality than ever, especially as people become aware of the impending shortage of natural resources.I propose to offer a modified renewable energy source in a new environment. The use of hydropower turbines for renewable energy generation is something common to many places across the globe, but the use of hydropower turbines in a building is not. In this paper I propose a system that utilizes greywater from high-rise residential buildings to create energy with hydropower turbines at the base of the building. Calculations show the system can produce energy, but improvements and changes need to be considered for this to be a commercially viable renewable energy source.
4

Advancing Membrane Technologies for Recovery of Phosphorus and Nitrogen from Human Urine

McCartney, Stephanie Nicole January 2022 (has links)
The existing linear economy approach to nutrient management has clear shortcomings including high expenditures for nutrient extraction and production of fertilizer as well as additional costs for nutrient removal at downstream waste water treatment plants (WWTPs) to prevent the pollution of aquatic environments. In a circular nutrient economy, phosphorus (P) and nitrogen (N) are removed from waste streams and captured as valuable fertilizer products in order to more sustainably reuse the resources in closed-loops and simultaneously protect receiving aquatic environments from harmful P and N emissions. The overarching aim of this thesis is to understand strategic approaches for nutrient recovery from wastewater and advance membrane technologies for P and N reclamation. The studies i.) approach nutrient recovery on a system-level to recognize optimal waste streams to target for P and N separation, ii.) advance membrane-based processes for nutrient recovery, and iii.) examine the economic viability of the nutrient recovery techniques.The thesis presents a thermodynamic and energy analysis of nutrient recovery from various waste streams of fresh and hydrolyzed urine, greywater, domestic wastewater, and secondary treated wastewater effluent. The analysis revealed comparative advantages in theoretical energy intensities for P and N recovery from nutrient-dense waste streams, such as fresh and hydrolyzed urine, compared to other more dilute sources. The thesis quantifies efficiencies required by separation techniques for nutrient reclamation to be competitive with the energy requirements of the prevailing industrial fertilizer production methods, i.e., phosphate mining and nitrogen fixation by the Haber-Bosch process. The dissertation examines and advances the performance of membrane-based processes for separation and recovery of P and N from diverted human urine. Donnan dialysis (DD), an ion-exchange membrane-based process, can capture and enrich orthophosphate, HxPO4(3−x)−, from source-separated urine. This work demonstrates the transport of Cl− driver ions down a concentration gradient, across an ion-exchange membrane to set up an electrochemical potential gradient that drives the transport of target HxPO4(3−x)− in the opposite direction, enabling P capture. Importantly, H2PO4− is transported against an orthophosphate concentration gradient, which achieves uphill transport of P. The thesis also provides a framework to better understand the impact of different ions in the water matrix on P recovery potential and kinetics. The thesis presents a novel operation of membrane distillation (MD) — isothermal membrane distillation with acidic collector (IMD-AC) — to selectively recover volatile ammonia, NH3, from hydrolyzed urine. The innovative isothermal and acidic collector features, respectively, suppressed undesired water permeation and enhanced ammonia vapor flux relative to conventional membrane distillation (CMD). The elimination of water flux in IMD-AC resulted in ≈95% savings in vaporization energy consumption relative to CMD. Critically, IMD-AC achieved uphill transport of ammoniacal nitrogen, i.e., transport against a concentration gradient, demonstrating the promising potential of the technique for N recovery. The dissertation proposes an integrated bipolar membrane electrodialysis (BPM-ED), DD, and IMD-AC system to drive the separation and recovery of orthophosphate and ammoniacal nitrogen from human urine. This work elucidates the role of pH and nutrient speciation (i.e., H2PO4− versus HPO42− and NH4+ versus NH3) on the performance of DD and IMD-AC. In the proposed configuration, BPM-ED generates acids and bases in situ to strategically control the pH of urine streams to benefit DD and IMD-AC performances. Strategic pH modification can enhance orthophosphate transport and selectivity in DD as well as ammonia transport and recovery potential in IMD-AC. Importantly, the analysis quantifies comparable specific energy consumptions of the proposed integrated membrane-based process to the existing approaches to P and N management. This thesis presents a preliminary economic assessment of onsite nutrient recovery employing DD and IMD-AC for respective P and N recovery from diverted urine. The analysis reveals opportunities to utilize widely-available waste chemical streams and recovered thermal energy to improve the economic viability of nutrient recovery. The largest capital expenditures are urine diversion toilets and additional piping for source-separation. Preliminary analysis demonstrates that employing urine diversion in public sanitation rooms, as opposed to private bathrooms, can reduce these capital expenditures. Furthermore, realizing savings from avoided costs for downstream nutrient removal at centralized wastewater treatment plants in addition to fertilizer revenue can enhance the economic viability of the approach. Overall, this dissertation critically informs nutrient recovery approaches and advances membrane-based processes for P and N reclamation to facilitate a paradigm shift from an inefficient linear nutrient economy to a sustainable circular nutrient economy. The work reveals opportunities to minimize energy intensity for nutrient separation, advance the performance of membrane-based techniques for selective and energy-efficient nutrient recovery from urine, and enhance the cost-competitiveness of nutrient reclamation. The findings of this work support nutrient recovery efforts and provide important insights that can be applied to other separation and resource recovery endeavors.
5

Hydroponics system for wastewater treatment and reuse in horticulture /

Oyama, Noraisha. January 2008 (has links)
Thesis (Ph.D.)--Murdoch University, 2008. / Thesis submitted to the Faculty of Sustainability, Environmental and Life Sciences. Includes bibliographical references (leaves 118-134)
6

Avaliação quantitativa de riscos microbiológicos (AQRM) associados à E. coli em águas cinza /

Pasin, Débora Brunheroto. January 2013 (has links)
Orientador: Rodrigo Braga Moruzzi / Banca: Marcelo de Julio / Banca: Gustavo Henrique Ribeiro da Silva / Resumo: O reúso de águas cinza apresenta-se como uma alternativa de ampliação da oferta de água que pode contribuir para a conservação dos recursos híbridos, perante a escassez da água, não apenas pela qualidade, mas também pela quantidade. Os riscos associados à exposição rotineira ou acidental dessa fonte de alternativa devem, entretanto, ser considerados, para que se possam estabelecer práticas seguras de reúso, uma vez que as águas de reúso podem apresentar patógenos, tais como: vírus, bactérias, protozoários e helmintos. O presente trabalho teve como objetivo avaliar quantitativamente os riscos microbiológicos das diversas fontes de exposições dos usuários a E. coli na água cinza sem tratamento, a fim de definir uma faixa de Valores Máximos Permitidos (VMP) por meio de conceito de riscos aceitáveis 10-3 e 10-6 pppa (por pessoa por ano), para as diversas finalidades de reúso. Para tal, foram avaliadas a exposição, a dose-resposta e a probabilidade de infecção para diferentes finalidades de reúso. O modelo de beta-Poisson foi empregado para avaliação da probabilidade de infecção. A dose infectante (N50), a concentração de microorganismos, a rota de exposição, os volumes ingeridos (acidentalmente e rotineiramente), os parâmetros de interação agente-hospedeiro (α e β), bem como a frequencia de exposição foram avaliados a partir de uma compilação sistemática de dados da literatura. E, por meio da Avaliação Quantitativa de Riscos Microbiológicos (AQRM), o maior risco de infecção identificado decorreu do reúso de águas cinza misturadas para a finalidade de balnearidade e irrigação de culturas alimentares por meio de ingestão de alimentos, incorrendo em risco de aproximadamente 9,9 pessoas de cada dez indivíduos expostos, sem considerar os efeitos de diluição da água. Esse cenário, resultou... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The reuse of greywater is presented as an alternative to increasing the supply of water that can contribute to the conservation of water resources against water scarcity, not only the quality but also the quantity. The risks associated with exposure routine or accidental this alternative source should, however, be considered, so that they establish safe practices of reuse, since reusing water may have pathogens, such as viruses, bacteria, protozoa and helminths. The present study aimed to quantitatively evaluate the microbiological risks of different sources of exposure of users to E. coli in untreated gray water, in order to define a range of Maximum Values Allowed (MVA) through the concept of acceptable risk 10-3 and 10-6 pppy (per person per year), for the various purposes of reuse. To this end, we evaluated the exposure, the dose -response and the probability of infection for different purpose reuse. The beta-Poisson model was used to assess the likehood of infection. The infective dose (N50), the concentration of microorganisms, the route of exposure, the volumes ingested (accidentally and roubinely), the parameters of agent-host interaction (α and β), and the frequency of exposure were evaluated from one systematic compilation of literature. And, through Quantitative Microbiological Risk Assessment (QMRA), the greatest risk of infection identified resulted from the reuse of greywater mixed for the purpose of bathing and irrigation of food crops through food intake, resulting in risk of approximately 9,9 out of ten people exposed individuals, without considering the effects dilution water. This situation has resulted in MVA 5.25 to 105 MPN/100 mL and 3.95 to 39.5 MPN/100 mL, respectively, to an acceptable risk of 10-3 ppy and 0.00 to 0.10 MPN/100 mL and 0.00 to 0.04 MPN/100mL simultaneously to risk of 10-6 pppy. The lowest risk of infection was due... (Complete abstract click electronic access below) / Mestre
7

Avaliação quantitativa de riscos microbiológicos (AQRM) associados à E. coli em águas cinza

Pasin, Débora Brunheroto [UNESP] 01 August 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-08-01Bitstream added on 2014-06-13T19:59:10Z : No. of bitstreams: 1 pasin_db_me_bauru.pdf: 597021 bytes, checksum: 186b1dd9901aafb4d694462951b7f7c7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O reúso de águas cinza apresenta-se como uma alternativa de ampliação da oferta de água que pode contribuir para a conservação dos recursos híbridos, perante a escassez da água, não apenas pela qualidade, mas também pela quantidade. Os riscos associados à exposição rotineira ou acidental dessa fonte de alternativa devem, entretanto, ser considerados, para que se possam estabelecer práticas seguras de reúso, uma vez que as águas de reúso podem apresentar patógenos, tais como: vírus, bactérias, protozoários e helmintos. O presente trabalho teve como objetivo avaliar quantitativamente os riscos microbiológicos das diversas fontes de exposições dos usuários a E. coli na água cinza sem tratamento, a fim de definir uma faixa de Valores Máximos Permitidos (VMP) por meio de conceito de riscos aceitáveis 10-3 e 10-6 pppa (por pessoa por ano), para as diversas finalidades de reúso. Para tal, foram avaliadas a exposição, a dose-resposta e a probabilidade de infecção para diferentes finalidades de reúso. O modelo de beta-Poisson foi empregado para avaliação da probabilidade de infecção. A dose infectante (N50), a concentração de microorganismos, a rota de exposição, os volumes ingeridos (acidentalmente e rotineiramente), os parâmetros de interação agente-hospedeiro (α e β), bem como a frequencia de exposição foram avaliados a partir de uma compilação sistemática de dados da literatura. E, por meio da Avaliação Quantitativa de Riscos Microbiológicos (AQRM), o maior risco de infecção identificado decorreu do reúso de águas cinza misturadas para a finalidade de balnearidade e irrigação de culturas alimentares por meio de ingestão de alimentos, incorrendo em risco de aproximadamente 9,9 pessoas de cada dez indivíduos expostos, sem considerar os efeitos de diluição da água. Esse cenário, resultou... / The reuse of greywater is presented as an alternative to increasing the supply of water that can contribute to the conservation of water resources against water scarcity, not only the quality but also the quantity. The risks associated with exposure routine or accidental this alternative source should, however, be considered, so that they establish safe practices of reuse, since reusing water may have pathogens, such as viruses, bacteria, protozoa and helminths. The present study aimed to quantitatively evaluate the microbiological risks of different sources of exposure of users to E. coli in untreated gray water, in order to define a range of Maximum Values Allowed (MVA) through the concept of acceptable risk 10-3 and 10-6 pppy (per person per year), for the various purposes of reuse. To this end, we evaluated the exposure, the dose -response and the probability of infection for different purpose reuse. The beta-Poisson model was used to assess the likehood of infection. The infective dose (N50), the concentration of microorganisms, the route of exposure, the volumes ingested (accidentally and roubinely), the parameters of agent-host interaction (α and β), and the frequency of exposure were evaluated from one systematic compilation of literature. And, through Quantitative Microbiological Risk Assessment (QMRA), the greatest risk of infection identified resulted from the reuse of greywater mixed for the purpose of bathing and irrigation of food crops through food intake, resulting in risk of approximately 9,9 out of ten people exposed individuals, without considering the effects dilution water. This situation has resulted in MVA 5.25 to 105 MPN/100 mL and 3.95 to 39.5 MPN/100 mL, respectively, to an acceptable risk of 10-3 ppy and 0.00 to 0.10 MPN/100 mL and 0.00 to 0.04 MPN/100mL simultaneously to risk of 10-6 pppy. The lowest risk of infection was due... (Complete abstract click electronic access below)
8

Optimising the use of small-scale greywater treatment plants in South Africa

Natha, Shaym 26 June 2015 (has links)
M.Ing. (Civil Engineering) / To relieve the extreme pressure placed on overburdened water and wastewater infrastructure, the reuse of light wastewater was identified as a possible source of water supply for non-potable applications. The light wastewater discharge intercepted on-site can be recycled, treated and thereafter distributed to fixtures for agricultural, sanitation and gardening based activities. Sources for this light wastewater stream includes bathroom showers, bath tubs, hand wash basins including that of kitchens, laundry and washing machine outflows of recyclable quality. This type of re-usable water is called greywater (GW). This on-site re-use concept has potential to offer greater potable water savings if correctly implemented. For the purpose of this research, this particular type of waste stream excluding the kitchen and laundry discharge was the water source considered for the supply to this greywater treatment plant (GWTP). In 2009, the Water Research Commission (WRC) funded a greywater pilot study in a joint venture between the University of Witwatersrand (WITS) and the University of Johannesburg (UJ). Over the last few years, this project had progressed with new outcomes each year. The pilot GWTP at Unit 51, Student Town, UJ in Auckland Park was used for the purpose of this study. The selected reuse application for the GW effluent was for toilet flushing. GW was supplied to two toilets in a residential student complex housing 16 female and male students i.e. 8 students on each floor. The highlights of the WRC study included: a lack of satisfactory treatment efficiency and a well-defined protocol to address the problems associated with the slightly poor quality of effluent produced (i.e. unpleasant odours, greyish appearance and the unacceptable microbial count). Determining and addressing the user perceptions and user education about GW usage, respectfully, was a significant component in the successful management of the project. In this report, a practical evaluation of three crucial components of the GWTP was completed. These three components viz. treatment efficiency, user perceptions and quality standards, were common aspects of concern for existing decentralised GWTP’s within residential or small commercial stands.
9

Human Mitochondrial DNA and Endogenous Bacterial Surrogates for Risk Assessment of Graywater Reuse

Zimmerman, Brian D. 17 October 2014 (has links)
No description available.
10

Quantifying the benefits of greywater systems

Wickstead, Frank Anthony 05 April 2011 (has links)
This thesis offers a decision support framework to establish the economic feasibility associated with considering the installation of a greywater system. Because of the potential dangers and lack of widespread knowledge of greywater systems, the study begins by providing an explanation of current greywater technology to include the history of the technology, an explanation of greywater as opposed to reclaimed water, the potential risks of greywater use, and the necessary components of a greywater system. This decision support framework can be used with any scale of greywater system to be installed within any scale of facility. The example of an typical Atlanta, Georgia, USA multifamily rental development is used within the study to explain the framework by showing a working model. The need for water conservation in Georgia is shown and how greywater use dovetails with the need to lower overall usage. The legality of greywater use in Georgia along with the specific legal uses is also shown. The findings are then made State of Georgia and use specific to a multifamily development. The decision support framework provided is a viable tool. The sample framework in chapter 5 shows that the implementation of a greywater unit in the sampled facility would save 5,060,739.6 gallons of potable water per year with a 10.49 year payback cycle.

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