A cada dia a disputa pelo uso da água entre os diversos setores aumenta gerando sérios conflitos entre os usuários. Para minimizar a crise da água, tem-se desenvolvido técnicas, estudos, projetos e medidas que visem a proteção e conservação dos recursos disponíveis. Neste contexto, a possibilidade de substituição de parte da água potável, para usos menos restritivos, por uma de qualidade inferior está cada vez mais em evidência. No entanto, a falta de regulamentação específica sobre o assunto pode trazer conseqüências indesejáveis como riscos à saúde pública e ao meio ambiente, criação de práticas inadequadas; conflitos de competências e de interesses e, até, o descrédito da prática do reúso de água por parte da população. Este trabalho visa propor as variáveis de qualidade e seus respectivos limites para água de reúso urbano não potável de modo a garantir que esta prática seja viável e segura. Para tanto, são apresentados os potenciais usos urbanos da água de reúso e os riscos associados; as experiências internacionais e nacionais dos programas de reúso; a legislação e diretrizes existentes. Com base na pesquisa concluiu-se que a qualidade da água está relacionada aos perigos do reúso de água, contaminação química e contaminação microbiológica, sendo esta a mais relevante. Desta forma, definiu-se como variáveis de controle: os coliformes termotolerantes que indicam a contaminação por microorganismos patogênicos; de sólidos dissolvidos totais que causam danos materiais como incrustação e corrosão; da matéria orgânica que pode causar o ressurgimento dos microorganismos e aumentar o consumo do agente de desinfecção; da turbidez que interfere no processo da desinfecção; do cloro residual que deverá garantir a eliminação dos organismos patogênicos e garantir um residual para evitar o ressurgimento de bactérias. / Every day the dispute for the use of water between the sectors increases creating serious conflicts between the users. To minimize the water crisis, several options have been looked for through development of techniques, studies, projects and measures that seek the protection and conservation of the available resources. In this context, the possibility of replacing part of the potable water for one of lower quality is more and more in evidence. However, the lack of specific regulation on the issue can bring undesirable consequences as risk to public health and to the environment; creation of inadequate practices; conflicts of competences and of interests; and mainly the precipitate condemnation of water reuse from part of the population. This paper aims to propose the variables and quality of their water limits for urban non-potable reuse in order to ensure that this practice is feasible and safe. For that, are presented the potential uses of reuse water and the associate risks; the national and international experiences of reuse programs; the existing legislation and guidelines; and proposed quality criteria for the reuse water seeking a safe practice. Each one of these items will be evaluated and then the quality criteria will be proposed as well as their concentration for urban reuse. Based on the research concluded that water quality is related to the dangers of reuse of water contamination, chemical and microbiological contamination, which is the more relevant. Thus, it was defined as control variables of the limits of the thermotolerant coliforms that indicate the contamination by pathogenic microorganisms; of total dissolved solids that cause incrustation and corrosion problems; of organic matter that can cause the resurgence of the microorganisms; of the turbidity that interferes in the disinfection process; of the residual chlorine that must guarantee the elimination of pathogenic organisms.

This thesis topic is the evaluation of recycled water in Crete, Greece. Recycled water is a derivative of fresh water and as such it can be regarded as a good of a similar nature to fresh water (at least for some of its uses such as irrigation). The departure point for this research was given by specific articles and principles of the 60/2000 Water Framework Directive. According to them, recycled water evaluation can be viewed as a corollary of this directive. Since Crete is a European region with intense water shortage problems, this was a good opportunity to apply the suggestions of the directive: solve the problem of water shortage internally (i. e. in Crete, with the island's own means and plans, since Crete can be regarded as a single river basin district), make the most of marginal waters while at the same time enhancing the environment. The evaluation of recycled water has been implemented through the involvement of two distinctive groups of people: farmers and consumers. Therefore, on the one hand, the research asks farmers whether they would be willing to use recycled water of certain qualities for the irrigation of olive trees and tomatoes and on the other hand, the research asks consumers whether they would be willing to use and pay for food products irrigated with recycled water. Results show there is social acquiescence on recycled water usage. This is confirmed by the correspondence of willingness to use recycled water between farmers and consumers. Conclusions from the willingness to use and willingness to pay models provide useful pricing and marketing signals for recycled water. Besides the evaluation of recycled water, another part of the research dealt with the role water plays in the production of olive oil and the confirmation of irrigation water shortages.

A cada dia a disputa pelo uso da água entre os diversos setores aumenta gerando sérios conflitos entre os usuários. Para minimizar a crise da água, tem-se desenvolvido técnicas, estudos, projetos e medidas que visem a proteção e conservação dos recursos disponíveis. Neste contexto, a possibilidade de substituição de parte da água potável, para usos menos restritivos, por uma de qualidade inferior está cada vez mais em evidência. No entanto, a falta de regulamentação específica sobre o assunto pode trazer conseqüências indesejáveis como riscos à saúde pública e ao meio ambiente, criação de práticas inadequadas; conflitos de competências e de interesses e, até, o descrédito da prática do reúso de água por parte da população. Este trabalho visa propor as variáveis de qualidade e seus respectivos limites para água de reúso urbano não potável de modo a garantir que esta prática seja viável e segura. Para tanto, são apresentados os potenciais usos urbanos da água de reúso e os riscos associados; as experiências internacionais e nacionais dos programas de reúso; a legislação e diretrizes existentes. Com base na pesquisa concluiu-se que a qualidade da água está relacionada aos perigos do reúso de água, contaminação química e contaminação microbiológica, sendo esta a mais relevante. Desta forma, definiu-se como variáveis de controle: os coliformes termotolerantes que indicam a contaminação por microorganismos patogênicos; de sólidos dissolvidos totais que causam danos materiais como incrustação e corrosão; da matéria orgânica que pode causar o ressurgimento dos microorganismos e aumentar o consumo do agente de desinfecção; da turbidez que interfere no processo da desinfecção; do cloro residual que deverá garantir a eliminação dos organismos patogênicos e garantir um residual para evitar o ressurgimento de bactérias. / Every day the dispute for the use of water between the sectors increases creating serious conflicts between the users. To minimize the water crisis, several options have been looked for through development of techniques, studies, projects and measures that seek the protection and conservation of the available resources. In this context, the possibility of replacing part of the potable water for one of lower quality is more and more in evidence. However, the lack of specific regulation on the issue can bring undesirable consequences as risk to public health and to the environment; creation of inadequate practices; conflicts of competences and of interests; and mainly the precipitate condemnation of water reuse from part of the population. This paper aims to propose the variables and quality of their water limits for urban non-potable reuse in order to ensure that this practice is feasible and safe. For that, are presented the potential uses of reuse water and the associate risks; the national and international experiences of reuse programs; the existing legislation and guidelines; and proposed quality criteria for the reuse water seeking a safe practice. Each one of these items will be evaluated and then the quality criteria will be proposed as well as their concentration for urban reuse. Based on the research concluded that water quality is related to the dangers of reuse of water contamination, chemical and microbiological contamination, which is the more relevant. Thus, it was defined as control variables of the limits of the thermotolerant coliforms that indicate the contamination by pathogenic microorganisms; of total dissolved solids that cause incrustation and corrosion problems; of organic matter that can cause the resurgence of the microorganisms; of the turbidity that interferes in the disinfection process; of the residual chlorine that must guarantee the elimination of pathogenic organisms.

No description available.

Thesis (M.S.)--University of Tennessee, Knoxville, 2003. / Title from title page screen (viewed Oct. 8, 2003). Thesis advisor: Kevin, G. Robinson. Document formatted into pages (viii, 98 p. : col. ill.). Vita. Includes bibliographical references (p. 73-79).

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

No description available.

No description available.

The study reported here was aimed at optimising the microfiltration (MF) membrane process applied to water reclamation. Polypropylene hollow fibre membrane (0.2 ??m) with high pressure backwahing was mainly used in this study. To obtain secondary effluent for microfiltration a biological treatment (UASB/SBR) was applied to brewery effluent. It was identified that loading at a rate below 14 kg COD/kLd will ensure the stable performance of UASB. An initial energy balance of the system (Biological and MF) shows a plant treating brewery effluent (4000 mg/L COD) could yield a net energy of 2.5 kWh/kL (yield from methane less the plant operating energy) at an optimised MF flux. For the MF of low solids feed it was found that crossflow has no benefit and that intermittent dead end filtration is less productive than dead-end cycles. It was also that found cycle time between air backwashes is strongly dependent on the imposed flux and the maximum TMP allowed. Analysis based on energy and capital cost indicates that if energy saving is the objective the unit needs to be operated at low imposed flux. However, if capital and energy costs are combined, cost efficient operation would be at about 60 to 70 L/m2.h for TMPmax of 20 kPa or above 80 L/m2.h for TMPmax of 50 kPa. For cycles with a TMPmax of 20 kPa, the specific cake resistance was constant over the range of imposed fluxes. However, for a TMPmax of 50 kPa the specific resistance was higher and increased with imposed flux, signifying compressible cake formation. Further analysis of the TMP profiles showed that the membrane resistance increased over a number of cycles and that the increase was higher at higher flux. To fully optimise the operation, it would be necessary to include these factors. Laboratory scale studies with yeast showed many similarities with secondary effluent filtration. However, some inconsistencies were observed at lower f1uxes, which need to be confirmed by further studies. Life cycle assessment of the membrane filtration process indicated that operating at low flux (10 Llm2.h) with higher TMPmax is the environmentally sound operational strategy. The analysis highlights the fact that the environmental impacts mainly come from the membrane operation (more than 85%). When alternative energy sources are considered, the least impact operational strategy shifts towards higher flux (in the vicinity of 30 l/m2.h). In-situ electrochemical cleaning using an electrolysis process indicated better flux recovery than traditional chemical cleaning. However, repeated cycles of fouling and cleaning showed electrochemically cleaned membranes have a higher fouling tendency than the chemically cleaned membrane. Initial characterisation of membrane surface properties after cleaning could not provide conclusive evidence for the cause of rapid fouling of the electrochemically cleaned membrane.

Thesis (Ph. D. - Renewable Natural Resources)--University of Arizona. / Includes bibliographical references.