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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.
201

Comportamento de cátions percolados oriundos da aplicação de água residuária de suinocultura em solo cultivado com milho / Cations leaching behavior from wastewater swine application in soil with corn growth

Zanuzo, Lusiani 19 July 2007 (has links)
Made available in DSpace on 2017-05-12T14:47:20Z (GMT). No. of bitstreams: 1 Lusiani Zanuzo.pdf: 1057343 bytes, checksum: 5bafdf204f0e33b83a453f814d119a9b (MD5) Previous issue date: 2007-07-19 / The objective of this work was evaluated the cation´s leaching corn planted and irrigated with swine waste water in lysimeters. The factors and levels of treatments were: four levels of with swine wastewater (112.5, 225.0, 337.5 and 450.0 m3 ha-1), two levels of chemical fertilization (50% and 75% of nitrogen recommend) and three repetitions. The time after sowing was considered analysis factor to evaluate the time effects accumulation of cations in soil. The irrigation was realized switching water and wastewater in each period of 15 days. The lysimeters was built with fiber boxes, capacity of 1 m3, 1.6 m of diameter, spacing of 0,4 x 0,5 m and 1,2 m of depth. The statistical analysis used was split-plot. The leaching´s concentrations were larger for the chemical elements in the following order: Na+ > K+ > Ca2+ > Mg2+. In general, the factor swine wastewater produced proportional larger concentrations in the leaching of Na+. The chemical fertilization factor influenced in the largest concentrations of the K+ leaching. The time after sowing influenced in the largest concentrations of Ca2+ and Mg2+ in the soil and of Na+ leaching. / O objetivo deste trabalho foi avaliar os cátions lixiviados em lisímetros preenchidos com solo tipo Latossolo Vermelho Distroférrico, cultivados com milho irrigado com água residuária de suinocultura. Os fatores estudados foram a água residuária em quatro níveis (112,5, 225,0, 337,5 e 450 m3/ha) e a adubação química em dois níveis (50% e 75% do nitrogênio recomendado para a cultura do milho) ao longo do ciclo da cultura. A irrigação foi realizada intercalando água e água residuária de suinocultura a cada 15 dias. Os cátions avaliados no solo e no percolado foram K+, Na+, Ca2+, Mg2+. O delineamento experimental foi em esquema fatorial 4x2, com três repetições por tratamento e avaliações em quatro períodos do desenvolvimento da planta. As médias foram comparadas pelo teste de Tukey a 5% de significância. Os resultados apontam que as concentrações médias dos lixiviados foram maiores para os elementos químicos estudados na seguinte ordem: Na+> K+ > Ca2+ >Mg2+. As taxas da água residuária de suinocultura produziram, proporcionalmente, maiores concentrações médias nos lixiviados para Na+, apenas no último período avaliado. A adubação química influenciou nas maiores concentrações do K+ lixiviado. De modo geral, ao longo do experimento, foram observadas maiores concentrações de Ca2+ e Mg2+ no solo e de Na+ no lixiviado.
202

Água residuária de suinocultura associada à adubação mineral No cultivo da soja: 18º ciclo / Swine wastewater associated with mineral fertilizer on soybean crop: 18º cycle

Pereira, Pâmela Aparecida Maldaner 10 February 2015 (has links)
Made available in DSpace on 2017-07-10T14:38:23Z (GMT). No. of bitstreams: 1 Pamela_A Maldaner Pereira.pdf: 440286 bytes, checksum: 5016ef422d50ec0e0a9188c3b2d4c6eb (MD5) Previous issue date: 2015-02-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / 18 Abstract: The reuse of water in agricultural soils is an ancient and promising effective 19 practice in the development of cultures and important water resources management tool. 20 The objective of this study was to evaluate the effects of continuous application of 21 swine wastewater in different doses, associated with mineral fertilizer, in eight years of 22 management in no-till system, about the chemical conditions of the soil and soybean. 23 The experiment was conducted in the field in typical Dystroferric Red Oxisol with a 24 very clayey texture. The wastewater doses of swine applied from the beginning in the experimental area were 0, 100, 200, 300 m3 ha-1 25 prior to the seeding, associated with the 26 presence and absence of mineral fertilizer. The results were submitted to normality tests, ANOVA and Tukey test. The dose of 100 m3 ha-1 27 of swine wastewater associated with 28 mineral fertilizer was efficient nutrition soybean requirements, without causing damage 29 to the soil. Attention should be paid to the possible accumulation of copper and zinc in 30 the soil over the years. / Resumo: O reúso de águas em solos agrícolas é uma prática antiga e promissora eficaz 4 no desenvolvimento das culturas e importante ferramenta de gestão de recursos hídricos. 5 O objetivo deste estudo foi avaliar os efeitos da aplicação continuada de água residuária 6 de suinocultura em diferentes doses, associada à adubação mineral, em oito anos de 7 manejo em sistema plantio direto, acerca das condições químicas do solo e da soja. O 8 experimento foi desenvolvido em Latossolo Vermelho distroférrico típico de textura 9 muito argilosa. As doses de água residuária de suinocultura aplicadas desde o início na área experimental foram 0, 100, 200, 300 m3 ha-1 10 antecedentes à semeadura, associadas 11 à presença e ausência de adubação mineral. Os resultados obtidos foram submetidos a testes de normalidade, análise de variância e teste de Tukey. A dose 100 m3 ha-1 12 de água 13 residuária de suinocultura associada à adubação mineral mostrou-se eficiente às 14 exigências nutricionais da soja, sem causar danos ao solo. Deve-se atentar ao possível 15 acúmulo de cobre e zinco no solo ao longo dos anos. 16 Palavras-chave: reúso de água, fertirrigação, dejetos suínos
203

Água residuária de suinocultura associada à adubação mineral No cultivo da soja: 18º ciclo / Swine wastewater associated with mineral fertilizer on soybean crop: 18º cycle

Mumbach, Mirian Carla 10 February 2015 (has links)
Made available in DSpace on 2017-07-10T14:38:23Z (GMT). No. of bitstreams: 1 MIRIAN_ CARLA MUMBACH.pdf: 461293 bytes, checksum: 75a3f1196bd41e9eb4f11513b5896a7c (MD5) Previous issue date: 2015-02-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The reuse of water in agricultural soils is an ancient and promising effective 19 practice in the development of cultures and important water resources management tool. 20 The objective of this study was to evaluate the effects of continuous application of 21 swine wastewater in different doses, associated with mineral fertilizer, in eight years of 22 management in no-till system, about the chemical conditions of the soil and soybean. 23 The experiment was conducted in the field in typical Dystroferric Red Oxisol with a 24 very clayey texture. The wastewater doses of swine applied from the beginning in the experimental area were 0, 100, 200, 300 m3 ha-1 25 prior to the seeding, associated with the 26 presence and absence of mineral fertilizer. The results were submitted to normality tests, ANOVA and Tukey test. The dose of 100 m3 ha-1 27 of swine wastewater associated with 28 mineral fertilizer was efficient nutrition soybean requirements, without causing damage 29 to the soil. Attention should be paid to the possible accumulation of copper and zinc in 30 the soil over the years. / O reúso de águas em solos agrícolas é uma prática antiga e promissora eficaz 4 no desenvolvimento das culturas e importante ferramenta de gestão de recursos hídricos. 5 O objetivo deste estudo foi avaliar os efeitos da aplicação continuada de água residuária 6 de suinocultura em diferentes doses, associada à adubação mineral, em oito anos de 7 manejo em sistema plantio direto, acerca das condições químicas do solo e da soja. O 8 experimento foi desenvolvido em Latossolo Vermelho distroférrico típico de textura 9 muito argilosa. As doses de água residuária de suinocultura aplicadas desde o início na área experimental foram 0, 100, 200, 300 m3 ha-1 10 antecedentes à semeadura, associadas 11 à presença e ausência de adubação mineral. Os resultados obtidos foram submetidos a testes de normalidade, análise de variância e teste de Tukey. A dose 100 m3 ha-1 12 de água 13 residuária de suinocultura associada à adubação mineral mostrou-se eficiente às 14 exigências nutricionais da soja, sem causar danos ao solo. Deve-se atentar ao possível 15 acúmulo de cobre e zinco no solo ao longo dos anos.
204

Requisitos e critérios de desempenho para sistema de água não potável de edifícios residenciais. / Requirements and performance criteria for non-potable water system of residential buildings.

Peixoto, Luciana de Melo 15 December 2008 (has links)
A utilização de fonte alternativa de água em edifícios residenciais vem sendo praticada de forma mais constante nos últimos anos, com objetivo de reduzir a demanda de água potável. No entanto, a utilização de água não potável exige critérios que devem ser respeitados, para preservar a saúde dos usuários, tendo em vista a possibilidade de contaminação da água potável fornecida pela concessionária. Assim, este trabalho tem como objetivo apresentar requisitos e critérios de desempenho que devem ser aplicados nas fases de projeto, execução e manutenção do sistema predial de água não potável. Para apoiar os projetistas, executores e gestores na tomada de decisão das diferentes etapas do processo foi também desenvolvida e aplicada uma ferramenta para análise de modo e efeito de falha (FMEA) dos requisitos desenvolvidos para o sistema de água não potável. Os resultados obtidos com a aplicação da ferramenta em edifício comprovaram a sua aplicabilidade e eficiência no sistema predial de água não potável. / The use of alternative source of water in residential buildings has been practiced in more constant in recent years aiming to reduce the demand for potable water (drinking water). However, the use of non-potable water requires criteria that must be respected to preserve the health of users, with a view to possible contamination of potable water supplied by the concessionaire. Therefore, this paper aims to present requirements and performance criteria, which must be implemented in phases of design, implementation and maintenance of the non-potable water system in building. To assist the designers, performers and managers in decision-making of the different stages of the process was also developed and implemented analyze with the tool failure mode effect analysis (FMEA) for the requirements developed for the non-potable water system in building. The results achieved by the tool showed its applicability and efficiency in non-potable water system in building.
205

A soil microbial response to urban wastewater application : bacterial communities and soil salinity

Aiken, Jane Tracy, University of Western Sydney, College of Health and Science, School of Natural Sciences January 2006 (has links)
Soils research at the University of Western Sydney, Hawkesbury Campus, was undertaken to investigate bacterial communities and soil salinity in an applied study. Microbial ecology was used to inform an understanding of conditions in soil irrigated with treated effluent. Several hypotheses were investigated examining changes in ecological organization conducted under laboratory and field conditions. Results indicated that relative abundance distributions for candidate forms of the bacteria community associated with higher and lower salinity, as defined using canonical correlation analysis, were reproducible between laboratory incubation experiments and field samples. The investigation is the first to apply the ecological parameter of richness and abundance to a study of microbial communities and their environment in order to determine soil conditions for sites irrigated with treated effluent. The thesis tests the theory and application of applying quantitative ecology to microbial community analysis. / Doctor of Philosophy (PhD)
206

"Recirculating aquaculture system integration of bivalve culture for effluent nutrient composition reduction" /

Myers, Amanda R. January 2006 (has links) (PDF)
Thesis (M.S.)--University of North Carolina at Wilmington, 2006. / Includes bibliographical references (leaves: 47-51)
207

Water Reuse as Part of San Diego's Water Portfolio

Shipps, Hillary P 18 May 2013 (has links)
San Diego imports 80 to 90 percent of its water supply, depending on conditions during any particular year. This high level of imports and low diversity of water supply have combined with climate change to generate an urgent need for increased conservation and diversification of San Diego's water supply. Water reuse is one option to mitigate this problem. An attempt was made in the early 1990s to recycle wastewater but the public reacted badly due to a combination of bad public relations, perceived environmental justice issues, and a psychological phenomenon called the yuck factor. With improved public relations and education, the project might go through this year.
208

A Study on Urban Water Reuse Management Modeling

Zhang, Changyu January 2005 (has links)
This research deals with urban water reuse planning and management modeling in the context of sustainable development. Rapid urbanization and population growth have presented a great challenge to urban water resources management. As water reuse may alleviate pollution loads and enhance water supply sources, water reuse is being recognized as a sustainable urban water management strategy and is becoming increasingly attractive in urban water resources management. An efficient water reuse planning and management model is of significance in promoting water reuse practices. This thesis introduces an urban water reuse management and planning model using optimization methods with an emphasis on modeling uncertainty issues associated with water demand and water quality. The model is developed in conjunction with the overall urban water system with considerations over water supply, water demand, water distribution, water quality, and wastewater treatment and discharge. The objective of the model is to minimize the overall cost of the system subject to technological, societal and environmental constraints. Uncertainty issues associated with water demand and treatment quality are modeled by introducing stochastic programming methods, namely, two-stage stochastic recourse programming and chance-constraint programming. The model is capable of identifying and evaluating water reuse in urban water systems to optimize the allocation of urban water resources with regard to uncertainties. It thus provides essential information in planning and managing urban water reuse systems towards a more sustainable urban water resources management. An application was presented in order to demonstrate the modeling process and to analyze the impact of uncertainties.
209

A Study on Urban Water Reuse Management Modeling

Zhang, Changyu January 2005 (has links)
This research deals with urban water reuse planning and management modeling in the context of sustainable development. Rapid urbanization and population growth have presented a great challenge to urban water resources management. As water reuse may alleviate pollution loads and enhance water supply sources, water reuse is being recognized as a sustainable urban water management strategy and is becoming increasingly attractive in urban water resources management. An efficient water reuse planning and management model is of significance in promoting water reuse practices. This thesis introduces an urban water reuse management and planning model using optimization methods with an emphasis on modeling uncertainty issues associated with water demand and water quality. The model is developed in conjunction with the overall urban water system with considerations over water supply, water demand, water distribution, water quality, and wastewater treatment and discharge. The objective of the model is to minimize the overall cost of the system subject to technological, societal and environmental constraints. Uncertainty issues associated with water demand and treatment quality are modeled by introducing stochastic programming methods, namely, two-stage stochastic recourse programming and chance-constraint programming. The model is capable of identifying and evaluating water reuse in urban water systems to optimize the allocation of urban water resources with regard to uncertainties. It thus provides essential information in planning and managing urban water reuse systems towards a more sustainable urban water resources management. An application was presented in order to demonstrate the modeling process and to analyze the impact of uncertainties.
210

The study of constructed wetland for treating livestock wastewater and the livestock sludge compost

Fu, Cheng-Kuei 18 August 2005 (has links)
In Taiwan, swine wastewater has become one of the major causes of the deterioration of surface water quality. To minimize the operational and maintenance cost of the conventional wastewater treatment utilities, less expensive natural treatment systems (e.g., aquatic plant treatment system) have been proposed to enhance the efficacy of existing three-stage treatment system (solid separation followed by anaerobic and aerobic treatment). Using the natural treatment system is an appropriate technology for treating livestock wastewater in tropical or subtropical regions or developing countries because it is inexpensive, easily maintained, and has environmentally friendly and sustainable characteristics. The main objectives of this study were to (1) examine the efficacy and capacity of using aquatic plant treatment system to polish the treated wastewater to meet the discharge standards in Taiwan (COD = 600 mg/L, BOD = 80 mg/L, and SS = 150 mg/L), (2) evaluate the potential of reusing the treated wastewater, (3) evaluate the feasibility of replacing the aerobic treatment process contained in the three-stage system with the aquatic plant system, and (4) improve the efficiency of sludge (obtained from the three-stage treatment system) composting process. In this study, a hog farm was selected as the case study site. An aquatic plant unit [13.5 (L) ¡Ñ 4 (W) ¡Ñ 3 (D)] planted with Eichhornia crassipes (water hyacinth) was placed after the aerobic system for wastewater polishment. Influent and effluent sa mples from each unit were collected and analyzed for water quality parameters including chemical oxygen demand (COD), biochemical oxygen demand (BOD), and suspended solids (SS). Water samples were collected monthly during the 15-month investigation period. Results show that the averaged COD, BOD, and SS concentrations were approximately 708, 83, and 123 mg/L, respectively after the three-stage treatment scheme. The observed COD, BOD, and SS concentrations dropped to 518, 56, and 48 mg/L, respectively which could meet the discharge standards. Thus, the aquatic plant treatment system played an important role in meeting the discharge standards for swine wastewater. More than 99% of all pollutants were removed by the three-stage system followed by the aquatic plant system. The effluent from the treatment system has been used for hog farm cleaning. Thus, the aquatic plant system has the potential to be applied as the final polishment process to enhance the treatment efficacy of swine wastewater. Results also show that it is feasible to replace the aerobic treatment process with the aquatic plant system from the cost and regulation compliance point of view. Results from the composting study show that rice straws could enhance the activity of microorganisms and also cause the increase the quantity of potassium in the compost pile. Moreover, mixing the water hyacinth in the compost pile could increase the quantity of nitrogen and phosphorous. Results also reveal that using ceramic bioballs as the filling materials could minimize the composting time due to the increase of permeability in the piles.

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