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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.
31

Avaliação da remoção de Giardia spp. e Cryptosporidium spp. em processos de tratamento de esgoto sanitário / Assessment of removal of Giardia spp. and Cryptosporidium spp. from wastewater treatment processes

Medeiros, Raphael Corrêa 27 September 2013 (has links)
Este trabalho teve o intuito de avaliar a eficiência de remoção de protozoários patogênicos - Giardia spp. e Cryptosporidium spp. - em processos de tratamento de esgoto sanitário por reator UASB, lodos ativados, filtro lento em areia e diferentes desinfetantes. A recuperação de cistos de Giardia e de oocistos de Cryptosporidium, realizada por diferentes metodologias e utilizando ColorSeed®, foi de, respectivamente, 85 e 20% em esgoto bruto, e 62,5 e 17,5% em efluente tratado, quando foi utilizado o método de tripla centrifugação. Cistos de Giardia foram encontrados em 100% as amostras de esgoto pesquisadas, com média de 1,5 x 104 cistos por litro e oocistos de Cryptosporidium em 31,4% com média 3,1 x 10² oocistos por litro, em esgoto bruto. No tratamento biológico por reator UASB seguido de Lodos Ativados, a remoção de cisto de Giardia e esporos de Clostridium perfringens foram estatisticamente menores que as remoções de E. coli e coliformes totais. Não foram encontrados (oo)cistos após o tratamento terciário realizado através da filtração lenta em areia. Houve remoção estatisticamente maior na ETE em escala plena para coliformes totais e Clostridium perfringens. E. coli e cistos de Giardia, em ambas ETEs, apresentaram remoções similares. Elevadas concentrações de (oo)cistos foram encontradas no lodo de esgoto, com grande porcentagem ainda viável. Com relação à desinfecção, entre as bactérias indicadoras, Clostridium perfringens foram mais resistentes ao cloro, ozônio e radiação ultravioleta. O efeito sinérgico, promovido pelas desinfecções sequenciais (clororadiação ultravioleta e ozônio-radiação ultravioleta), foi evidenciado em alguns experimentos para todas as bactérias estudadas. O cloro alterou a fluorescência dos cistos de Giardia e o ozônio, além de alterar a fluorescência, foi capaz de diminuir a concentração de cistos desse microrganismo. Pode-se concluir que as concentrações tanto de microrganismos indicadores como de protozoários patogênicos é bastante elevada, qualquer que seja o tipo de esgoto: bruto, efluente do reator UASB ou efluente do lodos ativados. Isso evidencia o extremo cuidado com que estes efluentes devem ser tratados, para posteriores usos ou lançamento em corpo receptor, em especial devido à presença de (oo)cistos ainda viáveis de Giardia spp. e Cryptosporidium spp. mesmo após o tratamento biológico por lodos ativados, e a necessidade de desinfecção do efluente. / This work aimed to evaluate the efficiency of removal of pathogenic protozoa - Giardia spp. and Cryptosporidium spp. - during wastewater treatment by UASB reactor, activated sludge, slow sand filter and different disinfectants. The recovery of Giardia cysts and of Cryptosporidium oocysts, performed by different methodologies and using ColorSeed®, was respectively of 85 and 20%, in raw wastewater and 62.5 and 17.5% in treated effluent, applying triple centrifugation method. Giardia cysts were found in 100% of the the sewage samples surveyed, with average of 1.5 x 104 cysts per liter and Cryptosporidium oocysts were found in 31.4% with average of 3.1 x 10² oocysts per liter, in raw wastewater. Giardia cyst and Clostridium perfringens spores removals were statistically lower than E. coli and total coliforms removal when applying the biological treatment by UASB reactor followed by Activated Sludge. There were no (oo) cysts after treatment tertiary accomplished by slow sand filtration. There was a statistically higher removal in the full scale WWTP for total coliforms and Clostridium perfringens; however, E. coli and Giardia cysts, in both WWTPs, presented the same removal efficiency. High concentrations of (oo)cysts were found in the sludge sludge, with a high percentage still viable. Regarding disinfection, among the indicating bacteria, Clostridium perfringens was more resistant to chlorine, ozone and ultraviolet radiation. The synergic effect promoted by sequential disinfections (chlorine-ultraviolet radiation and ozone-ultraviolet radiation) was evidenced in some experiments for all the bacteria studied. Chlorine altered the fluorescence of Giardia cysts and ozone, as well as change in fluorescence was able to decrease the concentration of this microorganism. It can be concluded that the concentrations of indicator microorganisms as well as of pathogenic protozoa is very high, regardless the kind of wastewater: raw, UASB reactor effluent or activated sludge effluent. This shows the extreme care that must be taken towards these effluents, for future reuse or simply release in the environment, mainly due to the presence of viable Giardia spp. and Cryptosporidium spp. (oo)cysts even after the activated sludge treatment, and the need of disinfection of the effluent.
32

Avaliação do desempenho de uma estação de tratamento de água com sistema de dupla filtração, em escala real / Evaluation of the performance of the water treatment station with a double filtration system in real scale

Saldanha, João Rodrigo 28 March 2002 (has links)
A tecnologia de tratamento com dupla filtração encontra-se em estágio relativamente elevado de desenvolvimento, porém, ainda são poucos os dados de operação em escala real. Este trabalho teve como objetivo avaliar um sistema de dupla filtração em escala real (ETA2) para tratamento de água, do serviço autônomo de água e esgoto da cidade de São Carlos - SP, que trata água bruta proveniente do Ribeirão do Feijão e é constituída de três unidades de filtração cada uma contendo um filtro ascendente e um descendente. Em uma primeira etapa foram levantadas as medidas das unidades de dupla filtração, caracterizado o material filtrante e avaliadas as condições operacionais da ETA 2. Posteriormente, foi estudada a situação geral da ETA por meio de diversos parâmetros (turbidez, pH, expansão da areia na lavagem, contagem de partículas, de coliformes totais e Escherichia. coli), para verificar os principais problemas. Em seguida, realizou-se uma comparação da ETA2 com uma Instalação Piloto de Dupla Filtração. Este trabalho permitiu concluir principalmente que: i) devido às baixas taxas de filtração de unidades filtrantes da ETA2, excessivas dosagens de coagulante e falta de controle de lavagens, geralmente foi baixa a produção efetiva de água (em torno de 90%); ii) o desempenho, algumas vezes insatisfatório das unidades de filtração ascendente e descendente, deveu-se principalmente à ineficiência da mistura de coagulante na água bruta, falta de areia nos filtros ascendentes e à diferença de granulometria nos filtros descendentes; iii) o desenvolvimento da perda de carga nos filtros ascendentes da ETA2 foi mais acentuado na Instalação Piloto devido à mistura de seus materiais filtrantes. / Water treatment by means of a double filtration system is in a relatively high stage of development, however, there are still few data on real scale operations. The aim of this work was to evaluate a double filtration system in a real scale (ETA2) for the treatment of water, of the autonomous service of water and sewer of the city of São Carlos - SP, which treats water from the Ribeirão do Feijão (name of a local river), and is constituted of three filtration units, each a contain a direct up-flow sand filter, and a rapid filter. In the first stage, the sand of the filters was characterized, and the operational conditions of the ETA2 were evaluated. Next, the general situation of the ETA was studied by means of several parameters (turbidity, pH, expansion of the sand during washing process, counting of particles, total coliforms and Escherichia coli), in a order to detect the main problems. Finally, a confrontation between the ETA2 an a double filtration pilot Plant was carried through. This study made infer that: I) due to the low filtration rates of the ETA2`s filtration units, excessive doses of coagulant and lack of control of the washings, the actual production of water was low (around 90%); ii) the sometimes insufficient performance of the direct up-flow sand filtration and rapid filtration systems was mainly caused by an inefficient mixing of the coagulant with the natural water, lack of sand in direct up-flow filters; iii) the building up of the lossof cargo in the direct up-flow san filtration in filters of the ETA2 was more accentuated than in the Pilot Plant due to the mixture of the filtration materials.
33

Avaliação da remoção de Giardia spp. e Cryptosporidium spp. em processos de tratamento de esgoto sanitário / Assessment of removal of Giardia spp. and Cryptosporidium spp. from wastewater treatment processes

Raphael Corrêa Medeiros 27 September 2013 (has links)
Este trabalho teve o intuito de avaliar a eficiência de remoção de protozoários patogênicos - Giardia spp. e Cryptosporidium spp. - em processos de tratamento de esgoto sanitário por reator UASB, lodos ativados, filtro lento em areia e diferentes desinfetantes. A recuperação de cistos de Giardia e de oocistos de Cryptosporidium, realizada por diferentes metodologias e utilizando ColorSeed®, foi de, respectivamente, 85 e 20% em esgoto bruto, e 62,5 e 17,5% em efluente tratado, quando foi utilizado o método de tripla centrifugação. Cistos de Giardia foram encontrados em 100% as amostras de esgoto pesquisadas, com média de 1,5 x 104 cistos por litro e oocistos de Cryptosporidium em 31,4% com média 3,1 x 10² oocistos por litro, em esgoto bruto. No tratamento biológico por reator UASB seguido de Lodos Ativados, a remoção de cisto de Giardia e esporos de Clostridium perfringens foram estatisticamente menores que as remoções de E. coli e coliformes totais. Não foram encontrados (oo)cistos após o tratamento terciário realizado através da filtração lenta em areia. Houve remoção estatisticamente maior na ETE em escala plena para coliformes totais e Clostridium perfringens. E. coli e cistos de Giardia, em ambas ETEs, apresentaram remoções similares. Elevadas concentrações de (oo)cistos foram encontradas no lodo de esgoto, com grande porcentagem ainda viável. Com relação à desinfecção, entre as bactérias indicadoras, Clostridium perfringens foram mais resistentes ao cloro, ozônio e radiação ultravioleta. O efeito sinérgico, promovido pelas desinfecções sequenciais (clororadiação ultravioleta e ozônio-radiação ultravioleta), foi evidenciado em alguns experimentos para todas as bactérias estudadas. O cloro alterou a fluorescência dos cistos de Giardia e o ozônio, além de alterar a fluorescência, foi capaz de diminuir a concentração de cistos desse microrganismo. Pode-se concluir que as concentrações tanto de microrganismos indicadores como de protozoários patogênicos é bastante elevada, qualquer que seja o tipo de esgoto: bruto, efluente do reator UASB ou efluente do lodos ativados. Isso evidencia o extremo cuidado com que estes efluentes devem ser tratados, para posteriores usos ou lançamento em corpo receptor, em especial devido à presença de (oo)cistos ainda viáveis de Giardia spp. e Cryptosporidium spp. mesmo após o tratamento biológico por lodos ativados, e a necessidade de desinfecção do efluente. / This work aimed to evaluate the efficiency of removal of pathogenic protozoa - Giardia spp. and Cryptosporidium spp. - during wastewater treatment by UASB reactor, activated sludge, slow sand filter and different disinfectants. The recovery of Giardia cysts and of Cryptosporidium oocysts, performed by different methodologies and using ColorSeed®, was respectively of 85 and 20%, in raw wastewater and 62.5 and 17.5% in treated effluent, applying triple centrifugation method. Giardia cysts were found in 100% of the the sewage samples surveyed, with average of 1.5 x 104 cysts per liter and Cryptosporidium oocysts were found in 31.4% with average of 3.1 x 10² oocysts per liter, in raw wastewater. Giardia cyst and Clostridium perfringens spores removals were statistically lower than E. coli and total coliforms removal when applying the biological treatment by UASB reactor followed by Activated Sludge. There were no (oo) cysts after treatment tertiary accomplished by slow sand filtration. There was a statistically higher removal in the full scale WWTP for total coliforms and Clostridium perfringens; however, E. coli and Giardia cysts, in both WWTPs, presented the same removal efficiency. High concentrations of (oo)cysts were found in the sludge sludge, with a high percentage still viable. Regarding disinfection, among the indicating bacteria, Clostridium perfringens was more resistant to chlorine, ozone and ultraviolet radiation. The synergic effect promoted by sequential disinfections (chlorine-ultraviolet radiation and ozone-ultraviolet radiation) was evidenced in some experiments for all the bacteria studied. Chlorine altered the fluorescence of Giardia cysts and ozone, as well as change in fluorescence was able to decrease the concentration of this microorganism. It can be concluded that the concentrations of indicator microorganisms as well as of pathogenic protozoa is very high, regardless the kind of wastewater: raw, UASB reactor effluent or activated sludge effluent. This shows the extreme care that must be taken towards these effluents, for future reuse or simply release in the environment, mainly due to the presence of viable Giardia spp. and Cryptosporidium spp. (oo)cysts even after the activated sludge treatment, and the need of disinfection of the effluent.
34

Utilização de filtração direta ascendente como pré-tratamento à filtração rápida descendente para tratamento de água para abastecimento / The use of direct up-flow filtration as a pretreatment for rapid filtration in drinking water production

Gusmão, Paulo Tadeu Ribeiro de 19 April 2001 (has links)
Em instalação piloto, de 06/1998 a 10/1999, utilizando-se água natural de superfície com baixas turbidez e cor, foram avaliados dois sistemas de dupla filtração, com pré-tratamento em filtração direta ascendente em areia com taxas de 200 a 360 m3/m2.dia (sistema S01) e em filtração direta ascendente em pedregulho com taxas de 80 a 190 m3/m2.dia (sistema S02) e com tratamento final em filtração rápida descendente com taxas de 115 a 480 m3/m2.dia. As dosagens do coagulante (produto comercial de sulfato de alumínio) foram definidas utilizando-se filtro de laboratório de areia, havendo indicações de coagulação no mecanismo de adsorção, com neutralização parcial de carga. Foram executadas descargas de fundo intermediárias nas unidades de filtração direta ascendente, com significativa redução na perda de carga no meio granular de pedregulho. A turbidez, cor aparente, Fe e Mn totais dos efluentes finais dos sistemas atenderam às Normas Brasileiras para produção de água potável. No sistema S02 o crescimento da perda de carga no meio granular foi menos intenso na unidade de filtração direta ascendente do que no filtro rápido descendente, ocorrendo o inverso no sistema S01, no qual, em alguns ensaios, o filtro rápido descendente mostrou-se desnecessário. As carreiras de filtração foram de 27 a 88 h no sistema S01 e de 14 a 35 h no sistema S02. Em determinados casos, a floculação predominou na unidade de filtração direta ascendente em pedregulho, prejudicando a qualidade do seu efluente. O sistema S02 mostrou-se mais vantajoso que o sistema S01, exceto quando, neste, a filtração rápida descendente foi desnecessária. / Based on me investigation carried out in pilot plant, from June 1998 to October 1999, using natural surface raw water with low turbidity and color, two systems of two-stage filtration have been evaluated. As a pretreatment, the first system (S01) used direct up-flow sand filtration (with filtration rates from 200 to 360 m3/m2.day), and the second system (S02) used direct up-flow roughing filtration (with filtration rates from 80 to 190 m3/m2.day), both with final treatment based on rapid filtration (with filtration rates from 115 to 480 m3/m2.day) The coagulant doses (commercial product of aluminum sulfate) have been established through the use of laboratory scale sand filter, presenting signs of coagulation in the adsorption mechanism, with partial charge neutralization. Intermediate bottom discharges in the direct up-flow filtration units have resulted in significant reduction in thee headloss in gravel granular medium. The turbidity, apparent-color, total iron and manganese concentrations of the final effluents of the systems have attended the Brazilian Standards for drinking water production. The increase of headloss in gravel granular medium in system S02 was smaller in me direct up-fiow filtration unit than in the rapid filter, the opposite occurring in system S01, where some tests have proved lhe rapid filter redundant. The filter runs time were 27 to 88 hours in system S01 and 14 to 35 hours in system S02. In certain cases, flocculation was predominant in the direct up-flow roughing filtration unit, jeopardizing the effiuent quality. System S02 has proved advantageous in relation to system S01, except when in system S01 the rapid filter was redundant.
35

Utilização de filtração direta ascendente como pré-tratamento à filtração rápida descendente para tratamento de água para abastecimento / The use of direct up-flow filtration as a pretreatment for rapid filtration in drinking water production

Paulo Tadeu Ribeiro de Gusmão 19 April 2001 (has links)
Em instalação piloto, de 06/1998 a 10/1999, utilizando-se água natural de superfície com baixas turbidez e cor, foram avaliados dois sistemas de dupla filtração, com pré-tratamento em filtração direta ascendente em areia com taxas de 200 a 360 m3/m2.dia (sistema S01) e em filtração direta ascendente em pedregulho com taxas de 80 a 190 m3/m2.dia (sistema S02) e com tratamento final em filtração rápida descendente com taxas de 115 a 480 m3/m2.dia. As dosagens do coagulante (produto comercial de sulfato de alumínio) foram definidas utilizando-se filtro de laboratório de areia, havendo indicações de coagulação no mecanismo de adsorção, com neutralização parcial de carga. Foram executadas descargas de fundo intermediárias nas unidades de filtração direta ascendente, com significativa redução na perda de carga no meio granular de pedregulho. A turbidez, cor aparente, Fe e Mn totais dos efluentes finais dos sistemas atenderam às Normas Brasileiras para produção de água potável. No sistema S02 o crescimento da perda de carga no meio granular foi menos intenso na unidade de filtração direta ascendente do que no filtro rápido descendente, ocorrendo o inverso no sistema S01, no qual, em alguns ensaios, o filtro rápido descendente mostrou-se desnecessário. As carreiras de filtração foram de 27 a 88 h no sistema S01 e de 14 a 35 h no sistema S02. Em determinados casos, a floculação predominou na unidade de filtração direta ascendente em pedregulho, prejudicando a qualidade do seu efluente. O sistema S02 mostrou-se mais vantajoso que o sistema S01, exceto quando, neste, a filtração rápida descendente foi desnecessária. / Based on me investigation carried out in pilot plant, from June 1998 to October 1999, using natural surface raw water with low turbidity and color, two systems of two-stage filtration have been evaluated. As a pretreatment, the first system (S01) used direct up-flow sand filtration (with filtration rates from 200 to 360 m3/m2.day), and the second system (S02) used direct up-flow roughing filtration (with filtration rates from 80 to 190 m3/m2.day), both with final treatment based on rapid filtration (with filtration rates from 115 to 480 m3/m2.day) The coagulant doses (commercial product of aluminum sulfate) have been established through the use of laboratory scale sand filter, presenting signs of coagulation in the adsorption mechanism, with partial charge neutralization. Intermediate bottom discharges in the direct up-flow filtration units have resulted in significant reduction in thee headloss in gravel granular medium. The turbidity, apparent-color, total iron and manganese concentrations of the final effluents of the systems have attended the Brazilian Standards for drinking water production. The increase of headloss in gravel granular medium in system S02 was smaller in me direct up-fiow filtration unit than in the rapid filter, the opposite occurring in system S01, where some tests have proved lhe rapid filter redundant. The filter runs time were 27 to 88 hours in system S01 and 14 to 35 hours in system S02. In certain cases, flocculation was predominant in the direct up-flow roughing filtration unit, jeopardizing the effiuent quality. System S02 has proved advantageous in relation to system S01, except when in system S01 the rapid filter was redundant.
36

Avaliação do desempenho de uma estação de tratamento de água com sistema de dupla filtração, em escala real / Evaluation of the performance of the water treatment station with a double filtration system in real scale

João Rodrigo Saldanha 28 March 2002 (has links)
A tecnologia de tratamento com dupla filtração encontra-se em estágio relativamente elevado de desenvolvimento, porém, ainda são poucos os dados de operação em escala real. Este trabalho teve como objetivo avaliar um sistema de dupla filtração em escala real (ETA2) para tratamento de água, do serviço autônomo de água e esgoto da cidade de São Carlos - SP, que trata água bruta proveniente do Ribeirão do Feijão e é constituída de três unidades de filtração cada uma contendo um filtro ascendente e um descendente. Em uma primeira etapa foram levantadas as medidas das unidades de dupla filtração, caracterizado o material filtrante e avaliadas as condições operacionais da ETA 2. Posteriormente, foi estudada a situação geral da ETA por meio de diversos parâmetros (turbidez, pH, expansão da areia na lavagem, contagem de partículas, de coliformes totais e Escherichia. coli), para verificar os principais problemas. Em seguida, realizou-se uma comparação da ETA2 com uma Instalação Piloto de Dupla Filtração. Este trabalho permitiu concluir principalmente que: i) devido às baixas taxas de filtração de unidades filtrantes da ETA2, excessivas dosagens de coagulante e falta de controle de lavagens, geralmente foi baixa a produção efetiva de água (em torno de 90%); ii) o desempenho, algumas vezes insatisfatório das unidades de filtração ascendente e descendente, deveu-se principalmente à ineficiência da mistura de coagulante na água bruta, falta de areia nos filtros ascendentes e à diferença de granulometria nos filtros descendentes; iii) o desenvolvimento da perda de carga nos filtros ascendentes da ETA2 foi mais acentuado na Instalação Piloto devido à mistura de seus materiais filtrantes. / Water treatment by means of a double filtration system is in a relatively high stage of development, however, there are still few data on real scale operations. The aim of this work was to evaluate a double filtration system in a real scale (ETA2) for the treatment of water, of the autonomous service of water and sewer of the city of São Carlos - SP, which treats water from the Ribeirão do Feijão (name of a local river), and is constituted of three filtration units, each a contain a direct up-flow sand filter, and a rapid filter. In the first stage, the sand of the filters was characterized, and the operational conditions of the ETA2 were evaluated. Next, the general situation of the ETA was studied by means of several parameters (turbidity, pH, expansion of the sand during washing process, counting of particles, total coliforms and Escherichia coli), in a order to detect the main problems. Finally, a confrontation between the ETA2 an a double filtration pilot Plant was carried through. This study made infer that: I) due to the low filtration rates of the ETA2`s filtration units, excessive doses of coagulant and lack of control of the washings, the actual production of water was low (around 90%); ii) the sometimes insufficient performance of the direct up-flow sand filtration and rapid filtration systems was mainly caused by an inefficient mixing of the coagulant with the natural water, lack of sand in direct up-flow filters; iii) the building up of the lossof cargo in the direct up-flow san filtration in filters of the ETA2 was more accentuated than in the Pilot Plant due to the mixture of the filtration materials.
37

IWESS, an integrated water, energy and sanitation solution : A holistic approach to reach sustainability trough organic waste management for the Lake Victoria Basin, Kenya

Martinsson, Erik, Martinsson, Emil, Säf, Sören January 2008 (has links)
The process of allocating necessary resources like clean water, fuel/energy and food have resulted in an unsustainable use of natural resources causing problems with Soil erosion, soil fertility, desertification, deforestation, eutrophication and global warming. The purpose of this study was to gain information on the functional design of a waste management system enabling the organic components of domestic waste to be processed as useful resources while at the same time allow them to be re-circulated. The main part of this study was carried out at the Kendu SDA Hospital in the Rachyonyo district in western Kenya. For the case of this study two main objectives where chosen. The first was to develop a principal technological solution using three classed “appropriate technologies” found suitable for the purpose namely biogas, ecological water treatment systems and slow sand filtration. The second was to further analyse each included technology to further develop their potential to fit the concept. Results from the pilot facilities where then to be retrieved from the actual component selection and construction process itself, with performance analysis left for future studies. The main purpose of the biogas system study has been to evaluate the original ideas of overall concept, details, materials and construction methods. The 1 m3 biogas system has improved significantly during the development process and is today not far from an implementation, i.e. construction on a slightly larger scale. The biogas system developed during the project has proven to have potential for digestion of both latrine and kitchen waste. Using the two as fuel for the process does not only remove a problem – it grants several benefits. The ecological waste water treatment system main objective was to design and construct a pilot SSF-wetland. Results show that the construction process for smaller scaled SSF systems is simple and does not require trained personnel or specialized equipment and that significant cost reduction can be made by using locally available materials. The slow sand filtration sub system concept is called PT SCX and though still in the stage of development proved to have great potential concerning both efficiency and sustainability. The PT SCX comprises the advantages of slow sand filtration with further development of individual system solutions. It was adapted to enable both integration to the IWESS solution and stand alone installations purifying even highly turbid surface water sources to drinking water quality. The result from the study confirms the suitability of the three included technologies, ecological waste water treatment, biogas and slow sand filtration to work in an integrated system called IWESS- Integrated Water Energy and Sanitation Solution. The combined subsystems can together with source separated sewage offer full resource recovery enabling recirculation of both nutrients and water. In addition the system can be designed as a net producer of renewable and emission free energy.
38

IWESS, an integrated water, energy and sanitation solution : A holistic approach to reach sustainability trough organic waste management for the Lake Victoria Basin, Kenya

Martinsson, Erik, Martinsson, Emil, Säf, Sören January 2008 (has links)
<p>The process of allocating necessary resources like clean water, fuel/energy and food have resulted in an unsustainable use of natural resources causing problems with Soil erosion, soil fertility, desertification, deforestation, eutrophication and global warming. The purpose of this study was to gain information on the functional design of a waste management system enabling the organic components of domestic waste to be processed as useful resources while at the same time allow them to be re-circulated. The main part of this study was carried out at the Kendu SDA Hospital in the Rachyonyo district in western Kenya. For the case of this study two main objectives where chosen. The first was to develop a principal technological solution using three classed “appropriate technologies” found suitable for the purpose namely biogas, ecological water treatment systems and slow sand filtration. The second was to further analyse each included technology to further develop their potential to fit the concept. Results from the pilot facilities where then to be retrieved from the actual component selection and construction process itself, with performance analysis left for future studies.</p><p>The main purpose of the biogas system study has been to evaluate the original ideas of overall concept, details, materials and construction methods. The 1 m3 biogas system has improved significantly during the development process and is today not far from an implementation, i.e. construction on a slightly larger scale. The biogas system developed during the project has proven to have potential for digestion of both latrine and kitchen waste. Using the two as fuel for the process does not only remove a problem – it grants several benefits.</p><p>The ecological waste water treatment system main objective was to design and construct a pilot SSF-wetland. Results show that the construction process for smaller scaled SSF systems is simple and does not require trained personnel or specialized equipment and that significant cost reduction can be made by using locally available materials.</p><p>The slow sand filtration sub system concept is called PT SCX and though still in the stage of development proved to have great potential concerning both efficiency and sustainability. The PT SCX comprises the advantages of slow sand filtration with further development of individual system solutions. It was adapted to enable both integration to the IWESS solution and stand alone installations purifying even highly turbid surface water sources to drinking water quality.</p><p>The result from the study confirms the suitability of the three included technologies, ecological waste water treatment, biogas and slow sand filtration to work in an integrated system called IWESS- Integrated Water Energy and Sanitation Solution. The combined subsystems can together with source separated sewage offer full resource recovery enabling recirculation of both nutrients and water. In addition the system can be designed as a net producer of renewable and emission free energy.</p>
39

Sistema de filtração lenta no tratamento de percolado do aterro sanitario de Limeira-SP / Slow sand filter in the treatment of leachate of the sanitary landfill of Limeira -SP

Pelegrini, Nubia Natalia de Brito 17 February 2006 (has links)
Orientador: Jose Euclides Stipp Paterniani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-06T12:32:37Z (GMT). No. of bitstreams: 1 Pelegrini_NubiaNataliadeBrito_M.pdf: 1010430 bytes, checksum: 1a5af5bc021dbf527427add6944a6e6d (MD5) Previous issue date: 2006 / Resumo: A disposição final de resíduos sólidos é uma prática que ainda traz sérios impactos ao meio ambiente. Nos aterros sanitários, os resíduos passam por processos físicos, químicos e biológicos de decomposição, gerando uma fração gasosa (composta principalmente por gases dióxido de carbono e metano) e uma fase líquida conhecida como chorume (ou percolado de aterro sanitário). O chorume de lixo é um líquido com elevado potencial poluente, os métodos convencionais utilizados em seu tratamento têm descartado-o com intensa coloração e alta toxicidade. Este trabalho teve como objetivo implantar em escala piloto um sistema de filtração lenta precedido de uma pré-filtração, apenas em manta sintética não tecida, para o tratamento de chorume de lixo ¿in natura¿, proveniente do aterro sanitário da cidade de Limeira-SP. O filtro lento foi constituído por um tanque cilíndrico de plástico tendo como meio filtrante areia e mantas sintéticas não tecidas. A taxa de filtração adotada durante os experimentos foi de 3 m3/m2.dia. O sistema de tratamento em estudo apresentou reduções consideráveis dos valores de alguns parâmetros de controle ambiental indicando a possibilidade do uso da filtração lenta para remediação de águas residuárias. As principais reduções obtidas referem-se a 40% de turbidez, 21% da coloração, 35% de dureza, 35% de carbono orgânico total (TOC) e reduções consideráveis de metais pesados (60% de cádmio, 30% de chumbo, 25% de cobre e 30% de cromo). Com relação à reutilização do chorume tratado em atividades agrícolas ainda são necessárias maiores reduções dos valores de parâmetros analíticos através da complementação com outras tecnologias de tratamento / Abstract: The final disposition of solids residues is a practice that still brings serious impacts to the environment. In sanitary landfill, the residues goes through physical, chemical and biological decomposition processes, generating into a gas phase (mainly composed by CH4 and CO2) and a liquid phase known as leachate. The waste leachate is a liquid with high pollutant potential. The conventional methods used in the treatment this residue have discarded him with intense coloration and high toxicity. This work had as objective implant in pilot scale a system of slow sand filtration preceded of a pré-filtration, only in non-woven synthetic fabrics, for the waste leachate treatment in natura, originating from the sanitary landfill of the city of Limeira-SP. The slow sand filter is constituted by a plastic cylindrical tank, sands and non-woven synthetic fabrics. The filtration rate adopted during the experiments it was of 3 m3/m2.dia. The treatment system in study presented considerable reductions of some values of environmental parameters control indicating the possibility of the use of the slow filtration for remediação of wastewaters. The main obtained reductions were 40% of turbidity, 21% of color, 35% of hardness, 35% of total organic carbon (TOC) and reductions considerably of heavy metals (60% of cadmium, 30% of lead, 25% of cupper and 30% of chrome). For the reuse of the treated leachate in agricultural activities are necessary larger reductions of some values of analytic parameters through the complementation with other treatment technologies. eywords: Landfill Leachate, Sanitary Landfill, Slow Sand Filtration, Reuse / Mestrado / Agua e Solo / Mestre em Engenharia Agrícola
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Kapacitetsminskning hos långsamfiltren vid Lovö och Norsborgs vattenverk : Studie av påverkande faktorer samt åtgärdsförslag / Reduced slow sand filtration capacity at the water treatment plants at Lovö and Norsborg : Reasons and ways on increasing the capacity

Mellander, Mattis January 2015 (has links)
Invånarantalet i Stockholm ökar och därmed också efterfrågan på dricksvatten. Stockholm Vatten VA AB fastslog i sin senaste prognos att kapaciteten hos deras vattenverk i Norsborg och på Lovö kommer att vara otillräcklig inom femton år och därmed måste ökas. Båda vattenverken tar vatten från Mälaren och renar detta genom flockning, sedimentering, snabbfiltrering, långsamfiltrering, UV-bestrålning samt tillsats av kloramin. Baserat på de senaste årens drifterfarenheter har långsamfiltrens kapacitet skrivits ned och är ett begränsande produktionssteg på båda verken. Detta examensarbete syftade till att fastställa orsakerna till kapacitetsminskningen och föreslå åtgärder. Undersökningen begränsades till Lovö vattenverk, men resultaten anses relevanta även för Norsborgs vattenverk.   De senaste åren har långsamsandfiltrens drifttid mellan rensningar minskat och tryckfallet i genomsnitt ökat. Här sågs att tryckfallet direkt efter rensning var högre i den undersökta periodens slut än under periodens början. Då filtrens belastning undersöktes konstaterades att filtreringshastigheten inte ökat och vattenkvaliteten inte försämrats. Utifrån detta drogs slutsatsen att kapacitetsminskningen inte berodde på ökad belastning.    Med hjälp av rör satta i filtersanden kunde tryckfallets fördelning över filterbäddens djup undersökas. I två av de undersökta filtren sågs ett kraftigt tryckfall i filtrens undre del. Då provgropar grävdes i filtren sågs ett tydligt gråaktigt lager vid den nivå där tryckfallet skett. Analyser av sandprover från filtren tydde på att en ackumulering av finkorniga sandpartiklar och organiskt material samt en lågporositet, gav det gråa lagret en låg mättad hydraulisk konduktivitet. Ackumuleringen av finkorniga sandpartiklar skulle kunna bero på att finkornigt material lyfts från filtrens hörn, där sandlagret är tunnare, och fördelas över resterande delar av filtret vid återfyllnad efter rensning.   Mätningar av porositet visade att filterbädden kompakteras då det belastas av de fordon som används vid rensning. Resultaten tyder dock på att packningens utbredning och omfattning är sådan att den inte har någon större effekt på tryckfallet i filtret. / Stockholm is growing and with it the demand for drinking water. To meet the demand the capacity of the two water treatment plants in Norsborg and at Lovö must be increased. Both plants use water from the lake Mälaren which is treated using flocculation, sedimentation, rapid filtration, slow sand filtration, UV-light and the addition of chloramine. The estimated capacity of the slow sand filters has decreased at both plants during the last few years and is limiting the total production capacity. This study aims to find the cause of the capacity decrease and make suggestions for how the capacity could be increased. Only the water treatment plant at Lovö was examined in this study, but the results are considered to be relevant for the water treatment plant in Norsborg as well.   During recent years the runtime of the filters has been decreasing and the overall loss of hydraulic head has increased. In several filters it was noted that the hydraulic head loss after filter cleaning had increased over time. Filter load was examined during the period in which the loss in capacity took place. Neither had the filtration rate increased nor had the water quality decreased. A higher load could therefore be ruled out as the source of the capacity loss.   Hydraulic head loss distribution over the depth of the filter beds was examined using steel pipes placed in the filter bed at different depths. In two filters a large hydraulic head loss was found at a narrow section in the bottom of the filters. Holes were dug in the filter beds, from which a distinct grey layer could be observed. Sand analyses showed that an accumulation of fine sand particles and organic matter combined with a low porosity could have been what caused the large hydraulic head loss in the layer. This material could have originated from the corners of the filters. During filter refill, fine material was observed being suspended from the corners and spread across the filter.   Measurements of sand porosity suggested that the filter bed is compacted by the machines used to clean the filters. This however seemed to have a negligible effect on the hydraulic head loss in the filters.

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