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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.
11

UtilizaÃÃo de Bioensaios para AvaliaÃÃo da Ecotoxicidade em ResÃduos de Esgotamento de CaminhÃo Limpa- Fossa: Lodo de Fossa SÃptica / Use of Bioassays for Assessment of Ecotoxicity of Waste Sewage Truck Clean-Fossa: Septic sludge

GeÃsa Vieira Vasconcelos 25 May 2012 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O uso agrÃcola do lodo de esgoto à uma alternativa que apresenta vantagens ambientais quando comparada a outras prÃticas de destinaÃÃo final e a sua aplicaÃÃo no solo pode trazer benefÃcios à agricultura. O presente estudo teve como objetivo avaliar a toxicidade aguda de resÃduos de caminhÃes limpa-fossa (lodo sÃptico), de diferentes residÃncias atravÃs da utilizaÃÃo de bioensaios, com trÃs organismos bioindicadores de toxicidade, os microcrustÃceos (Daphnia magna e Daphnia similis) e bactÃrias (Vibrio fischeri) no Sistema MicrotoxÂ. Primeiramente foi feita a caracterizaÃÃo fÃsico-quÃmica, microbiolÃgica e metais pesados dos resÃduos esgotados dos caminhÃes limpa-fossa e posteriormente foram realizados testes de toxicidade. As coletas foram realizadas quinzenalmente na ETE SÃo CristÃvÃo/CAGECE, em Fortaleza-CE, onde as amostras foram levadas ao laboratÃrio para realizar as anÃlises de pH, temperatura, alcalinidade, condutividade elÃtrica, sÃrie de sÃlidos, DBO, DQO, sÃrie de nitrogÃnio, fÃsforo e coliformes termotolerantes. Observou-se que estes resÃduos apresentaram concentraÃÃes bem mais elevadas que as de esgoto domÃstico e tambÃm com caracterÃsticas bastante variÃveis. A fraÃÃo volÃtil representa cerca de 65% dos sÃlidos totais e a relaÃÃo SV/ST foi de 0,6 indicando uma possÃvel estabilidade de acordo com a CONAMA 375/2006. TambÃm foram realizadas anÃlises de metais pesados (CÃdmio, Cromo, ManganÃs, NÃquel, Zinco, Chumbo, Ferro e Cobre) para verificar se tinha alguma correlaÃÃo com a toxicidade. Todas as amostras esgotadas de caminhÃes limpa-fossa apresentaram toxicidade aguda para os trÃs microorganismos Daphnia magna, Daphnia similis e Vibrio fischeri com mÃdia de CE50 igual à 54%, 41% 52% respectivamente, sendo todos considerados tÃxicos. Com relaÃÃo à sensibilidade a Daphnia similis foi o organismo que apresentou maior sensibilidade para resÃduos sÃpticos, pois quanto menor o CE50 mais tÃxica à a amostra. Pelos resultados obtidos, os resÃduos de caminhÃes limpa-fossa apresentaram toxicidade e nÃo poderiam ser utilizados na agricultura sem um prÃvio tratamento para a remoÃÃo da toxicidade. / O uso agrÃcola do lodo de esgoto à uma alternativa que apresenta vantagens ambientais quando comparada a outras prÃticas de destinaÃÃo final e a sua aplicaÃÃo no solo pode trazer benefÃcios à agricultura. O presente estudo teve como objetivo avaliar a toxicidade aguda de resÃduos de caminhÃes limpa-fossa (lodo sÃptico), de diferentes residÃncias atravÃs da utilizaÃÃo de bioensaios, com trÃs organismos bioindicadores de toxicidade, os microcrustÃceos (Daphnia magna e Daphnia similis) e bactÃrias (Vibrio fischeri) no Sistema MicrotoxÂ. Primeiramente foi feita a caracterizaÃÃo fÃsico-quÃmica, microbiolÃgica e metais pesados dos resÃduos esgotados dos caminhÃes limpa-fossa e posteriormente foram realizados testes de toxicidade. As coletas foram realizadas quinzenalmente na ETE SÃo CristÃvÃo/CAGECE, em Fortaleza-CE, onde as amostras foram levadas ao laboratÃrio para realizar as anÃlises de pH, temperatura, alcalinidade, condutividade elÃtrica, sÃrie de sÃlidos, DBO, DQO, sÃrie de nitrogÃnio, fÃsforo e coliformes termotolerantes. Observou-se que estes resÃduos apresentaram concentraÃÃes bem mais elevadas que as de esgoto domÃstico e tambÃm com caracterÃsticas bastante variÃveis. A fraÃÃo volÃtil representa cerca de 65% dos sÃlidos totais e a relaÃÃo SV/ST foi de 0,6 indicando uma possÃvel estabilidade de acordo com a CONAMA 375/2006. TambÃm foram realizadas anÃlises de metais pesados (CÃdmio, Cromo, ManganÃs, NÃquel, Zinco, Chumbo, Ferro e Cobre) para verificar se tinha alguma correlaÃÃo com a toxicidade. Todas as amostras esgotadas de caminhÃes limpa-fossa apresentaram toxicidade aguda para os trÃs microorganismos Daphnia magna, Daphnia similis e Vibrio fischeri com mÃdia de CE50 igual à 54%, 41% 52% respectivamente, sendo todos considerados tÃxicos. Com relaÃÃo à sensibilidade a Daphnia similis foi o organismo que apresentou maior sensibilidade para resÃduos sÃpticos, pois quanto menor o CE50 mais tÃxica à a amostra. Pelos resultados obtidos, os resÃduos de caminhÃes limpa-fossa apresentaram toxicidade e nÃo poderiam ser utilizados na agricultura sem um prÃvio tratamento para a remoÃÃo da toxicidade. / A way to recycle the nutrients and organic matter from sewage sludge from septic tanks and cesspools would return those elements to biogeochemical cycles. The agricultural use of sewage sludge is an alternative that provides environmental benefits when compared to other final disposal practices and its application in soil can bring benefits to agriculture. The present study aimed to evaluate the acute toxicity of clean trucks (septic sludge) from different homes through the use of bioassays, with three bodies bioindicators of toxicity, the microcrustaceans (Daphnia magna and Daphnia similis) and bacteria (Vibrio fischeri) in the Microtox  System. First was made the physico-chemical, microbiological characterization and heavy metals waste exhausted clean trucks and trench-toxicity tests were carried out at a later date. The collections were held fortnightly in the ETE SÃo CristÃvÃo, where samples were brought to the laboratory to perform the analyses of pH, alkalinity, temperature, electrical conductivity, solids, BOD, COD, nitrogen, phosphorus and termotolerantes coliforms. It was noted that such waste presented well concentrations higher than those of domestic sewage and also features plenty of variables. The volatile fraction accounts for around 65% of total solids and SV/ST was 0.6, indicating that the septic tanks and septic sludge can be considered stable according to the CONAMA 375/2006. Were also conducted analyses of heavy metals (Cadmium, chromium, manganese, nickel, zinc, lead, iron and copper) to verify that had some correlation with toxicity. All samples clean truck depleted-fossa showed acute toxicity for microorganism three Daphnia magna, Daphnia similis, and Vibrio fischeri averaging equal to 54%, EC50 41% 52% respectively, all of which are considered toxic. With respect to sensitivity to Daphnia similis was the body that has greater sensitivity to septic waste, because the lower the EC50 is more toxic to sample. By the results obtained, the clean trucks waste-fossa are toxic and could not be used in agriculture without a prior treatment for the removal of toxicity / A way to recycle the nutrients and organic matter from sewage sludge from septic tanks and cesspools would return those elements to biogeochemical cycles. The agricultural use of sewage sludge is an alternative that provides environmental benefits when compared to other final disposal practices and its application in soil can bring benefits to agriculture. The present study aimed to evaluate the acute toxicity of clean trucks (septic sludge) from different homes through the use of bioassays, with three bodies bioindicators of toxicity, the microcrustaceans (Daphnia magna and Daphnia similis) and bacteria (Vibrio fischeri) in the Microtox  System. First was made the physico-chemical, microbiological characterization and heavy metals waste exhausted clean trucks and trench-toxicity tests were carried out at a later date. The collections were held fortnightly in the ETE SÃo CristÃvÃo, where samples were brought to the laboratory to perform the analyses of pH, alkalinity, temperature, electrical conductivity, solids, BOD, COD, nitrogen, phosphorus and termotolerantes coliforms. It was noted that such waste presented well concentrations higher than those of domestic sewage and also features plenty of variables. The volatile fraction accounts for around 65% of total solids and SV/ST was 0.6, indicating that the septic tanks and septic sludge can be considered stable according to the CONAMA 375/2006. Were also conducted analyses of heavy metals (Cadmium, chromium, manganese, nickel, zinc, lead, iron and copper) to verify that had some correlation with toxicity. All samples clean truck depleted-fossa showed acute toxicity for microorganism three Daphnia magna, Daphnia similis, and Vibrio fischeri averaging equal to 54%, EC50 41% 52% respectively, all of which are considered toxic. With respect to sensitivity to Daphnia similis was the body that has greater sensitivity to septic waste, because the lower the EC50 is more toxic to sample. By the results obtained, the clean trucks waste-fossa are toxic and could not be used in agriculture without a prior treatment for the removal of toxicity
12

Tratamento dos resíduos de fossas e tanques sépticos em um sistema de alagado construído / Septic tanks and cesspols residues treatment at a constructed wetland system

Siqueira, Elisa Rodrigues 31 March 2014 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-08-26T18:27:33Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tratamento dos resíduos de fossas e tanques sépticos em um sistema de alagado construído.pdf: 3758497 bytes, checksum: 51e75f00b9f942fa3c8bcb520f75bbea (MD5) / Made available in DSpace on 2014-08-26T18:27:33Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tratamento dos resíduos de fossas e tanques sépticos em um sistema de alagado construído.pdf: 3758497 bytes, checksum: 51e75f00b9f942fa3c8bcb520f75bbea (MD5) Previous issue date: 2014-03-31 / Due to the lack of public sewer service in the country, Individual and Household Sewage Disposal Treatment Systems (SITDE) are still widely used in Brazil. The SITDE require cleaning maintenance and at the time of execution of this cleaning occurs the generation of the called Pit and Septic Tanks Waste (RFTS). This material has high load of pollutants and presence of pathogenic organisms and must be properly designed to ensure the quality of the environment and safeguard public health. In this context, low cost and potential for deployment in small settlements technologies emerge as an alternative of treatment. This study aimed to evaluate the efficiency of the Constructed Wetlands System (SAC) with the Vetiver plant species (Chrysopogon zizanioides) in the treatment of the liquid fraction of the RFTS. An experimental system was built with the deployment of two identical tanks. One tank received the vegetation and the other operated as a control treatment. The tanks were filled with a substrate consisting of gravel # 0, gravel # 1 and medium sand. The constructed wetland system (SAC) acted under a descending vertical subsurface flow and RFTS was applied on the system under batch, remaining in the tanks for a period of six (6) days. The RFTS influent to the treatment system was characterized according to the parameters of pH, total oil and grease, ammonia nitrogen, settleable solids, total coliforms, Escherichia coli, surface, solid fixed solids, volatile solids, Biochemical Oxygen Demand (BOD) and total phosphorus. The RFTS treated by SAC was analyzed according to the same parameters and the results were compared with the stipulations for disposition in water bodies of class 2, according to Resolution 430/2011 of Conama and Goiás State Decree 1.745/1979. The attributes removal efficiency was calculated considering the phenomenon of evapotranspiration, which showed an average rate of 38.11% in the SAC. The tributary RFTS system showed a great variability in the concentrations of the attributes. The results were subjected to F test (5% probability). Statistically, the only differed treatments between the tank vegetated and the tank control was removal of BOD which was more effective WS with the average removal of 86.80 %, while the tank control showed an average increase of 65.94 %. The average concentrations output WS met the requirements under federal and state law , except for E. coli showed an average outlet concentration can change the class of the receptor. Statistically, the treatments (vegetated tank and control tank) differed only for the BOD removal, which was more effective for the SAC, with the average removal of 86.80%, while the tank control showed an average increase of 65.94%. The average concentrations of SAC output attended the provided by the federal and state laws or release in Class 2 water. / Devido à carência do serviço público de esgotamento sanitário no país, os Sistemas Individuais de Tratamento e Disposição de Esgoto Doméstico (SITDE) ainda são muito utilizados. Os SITDE necessitam de manutenção com realização de limpeza e, no momento da execução desta limpeza ocorre a geração do chamado Resíduo de Fossas e Tanques Sépticos (RFTS). Este material possui elevada carga de poluentes e presença de organismos patogênicos devendo ser destinado corretamente de forma a garantir a qualidade do meio ambiente e preservar a saúde pública. Neste contexto, tecnologias de baixo custo e com potencial para implantação em pequenos núcleos populacionais surgem como uma alternativa de tratamento. Este trabalho objetivou avaliar a eficiência do Sistema de Alagado Construído (SAC) com a espécie vegetal capim Vetiver (Chrysopogon zizanioides) no tratamento da fração líquida dos RFTS. Foi construído um sistema experimental com a implantação de dois tanques idênticos. Um tanque recebeu a vegetação e o outro operou como controle (testemunha). Os tanques foram preenchidos com substrato formado por brita #0, brita #1 e areia média. O sistema de alagado construído (SAC) atuou em regime de fluxo vertical subsuperficial descendente e o RFTS foi aplicado no sistema em regime de batelada permanecendo nos tanques por um período de 6 (seis) dias. O RFTS afluente ao sistema de tratamento foi caracterizado segundo os parâmetros pH, óleos e graxas totais, nitrogênio amoniacal, sólidos sedimentáveis, coliformes totais, Escherichia coli, sólidos totais, sólidos fixos, sólidos voláteis, Demanda Bioquímica de Oxigênio (DBO) e fósforo total. O RFTS tratado pelo SAC foi analisado conforme os mesmos parâmetros e os resultados foram comparados com o estipulado para a disposição em corpos hídricos de classe 2, conforme a Resolução 430/2011 do Conama e o Decreto estadual 1.745/1979, do Estado de Goiás. A eficiência na remoção dos atributos foi calculada considerando o fenômeno da evapotranspiração, que apresentou taxa média de 38,11% no SAC. O RFTS afluente ao sistema experimental apresentou grande variabilidade nas concentrações dos atributos. Os resultados foram submetidos ao teste F (5% de probabilidade). Estatisticamente os tratamentos (tanque vegetado e tanque controle) diferiram apenas para a remoção da DBO onde o SAC foi mais eficaz com a remoção média de 86,80%, enquanto o tanque controle apresentou incremento médio de 65,94%. As concentrações médias de saída do SAC atenderam ao disposto pelas legislações federal e estadual para lançamento em corpos hídricos de classe 2.
13

Water and Health in the Nandamojo Watershed of Costa Rica: Community Perceptions towards Water, Sanitation, and the Environment

Mcknight, James 13 June 2014 (has links)
Understanding the relationships between human health, water, sanitation, and environmental health is a requirement to understanding the challenges that face researchers when it comes to addressing global health relating to water and sanitation. Access to improved water and sanitation is not only a precondition to health, but to all aspects of daily living. Target 7.C of the Millennium Development Goals (MDGs) addresses worldwide disparities in access to improved water and sanitation by calling for the reduction in "half of the proportion of people without sustainable access to safe drinking water and sanitation by 2015". Over 90% of the population of Costa Rica has access to improved water and sanitation, thus exceeding the water and sanitation targets for the Millennium Development Goals (MDGs). Despite having access to water and sanitation, little is known whether communities are only interested in access or if quality and quantity of water and sanitation systems are as equally as important. Target 7.c of the MDGs does not include water quality in the definition of safe water. Furthermore, the use of the words "safe" and "improved" in the target are often interchanged and can be misleading, especially when considering the impact of water quality on population health. In Costa Rica, households in the Nandamojo watershed have access to improved water and sanitation; it is unclear whether the drinking water is potable with respect to Costa Rican and the World Health Organization (WHO) water quality standards. The impact of leaking septic systems on human and environmental health is also unknown. Illnesses associated with recreational water are an increasing public health problem, causing a great burden of disease in bathers every year. The global health impact of infectious diseases associated with recreational water exposure has been estimated at around three million disability-adjusted life years (DALYs) per year, resulting in an estimated economic loss of around twelve billion dollars per year. Fecal and chemical contamination of recreational water is a concern, especially in areas of non-point source pollution. Health-based water monitoring is often conducted in recreational waters as a tool for assessing risk. In Costa Rica, recreational water sampling is conducted at coastal beach areas only, neglecting other surface waters used by residents and tourists. Community perspectives regarding recreational water use and the associated risks are limited. Understanding these perspectives will enable public health professionals to better target community needs, such as education and to address the concerns of participating communities. This dissertation was divided into three chapters. The first chapter explored community perceptions on improved water and sanitation, the second chapter assessed community water systems and the risk of acute diarrheal disease, and the third chapter captured community perceptions on recreational water use and the risk of waterborne illness. Methodologies for water sampling and analyses were used to assess water quality, while household interviews and focus groups were conducted to capture qualitative data. Results from the first chapter showed participants had positive perceptions towards their improved water and sanitation systems. Household interviews revealed almost half of the respondents had concerns with water quality, while less than 25% did not think their septic tanks leaked or overflowed during rain events. Focus group discussions revealed common themes. Participants identified water quality, health, pipes, water scarcity, odors, insects, and overflow/infiltration of water and sanitation to be important issues. Participants revealed convenience, improved health and safety and the lack of odors to be themes directly related to customer satisfaction of improved water and sanitation. Results from the second study revealed 57% of household samples had total coliform bacteria above the Costa Rican standard for safe drinking water exceeding the single standard limit of zero, while 61% failed the World Health Organization standard for fecal coliforms exceeding the single standard limit of zero. AGII was identified in 41 of the 378 household residents (11%). The odds ratio for AGII among household residents with a water sample positive for total coliforms was 1.88 (0.81-3.17). Fecal coliforms were statistically significant for those with AGII (OR = 3.19, 1.43-7.12). Regression modeling analyses revealed individuals with AGII and household drinking water positive for fecal coliforms to be statistically significant (OR = 3.01, 1.33 - 6.84), while other covariates (total coliforms, gender, treated water, and families) also had odds ratios greater than one, but were not significant. Results from the third chapter indicated most respondents felt recreational water sources, such as streams and rivers were contaminated with human, animal, and chemical wastes. Focus group participants also stated they did not use inland waters for recreational purposes for these reasons. However, many did admit using marine water for recreational bathing and felt these areas were not contaminated. These beliefs did coincide with the water quality results from freshwater sources, but not marine sources. Fecal coliform contamination was widespread throughout the watershed in freshwater sources. Marine water samples failed the World Health Organization (WHO) and Costa Rican recreational water standards for fecal coliform and enterococci in 36% and 6% of the samples, respectively. The overall results of this dissertation suggest that the definitions of improved water and sanitation have to include, at a minimum, water quality, water quantity, proper construction and containment of storage tanks, and oversight and maintenance of these systems. Given the challenges facing communities in the Nandamojo watershed regarding water and sanitation, it is essential for scientists, researchers, policy makers, water committees, health providers, and community members to design and implement strategies in water resource management and proper waste management. Communities and water committees would also be best served if they worked with government agencies to conduct concurrent testing of both recreational water and drinking water, especially since both them target many of the same parameters.
14

Integrated land capability for ecological sustainability of on-site sewage treatment systems

Al-Shiekh Khalil, Wael R. January 2005 (has links)
The research project was formulated to solve serious environmental and possible public health problems in rural and regional areas caused by the common failure of soil disposal systems used for application of effluent from on-site domestic sewage treatment systems. On-site sewage treatment systems adopt a treatment train approach with the associated soil disposal area playing a crucial role. The most common on-site sewage treatment system that is used is the conventional septic tank and subsurface effluent disposal system. The subsurface effluent disposal area is given high priority by regulatory authorities due to the significant environmental and public health impacts that can result from their failure. There is generally very poor householder maintenance of the treatment system and this is compounded by the failure of the effluent disposal area resulting in unacceptable surface and groundwater contamination. This underlies the vital importance of employing reliable science-based site suitability assessment techniques for effluent disposal. The research undertaken investigated the role of soil physico-chemical characteristics influencing the behaviour of effluent disposal areas. The study was conducted within the Logan City Council area, Queensland State, Australia. About 50% of the Logan region is unsewered and the common type of on-site sewage treatment used is a septic tank with subsurface effluent disposal area. The work undertaken consisted of extensive field investigations, soil sampling and testing, laboratory studies and extensive data analysis. In the field study, forty-eight sites were investigated for their effluent application suitability. The sites were evaluated based on the soil physico-chemical characteristics. The field investigation indicated that there were nine soil orders in the study area. These soil orders were Dermosols, Chromosols, Kandosols, Kurosols, Vertosols, Sodosols, Tenosols, Rudosols and Anthrosols. The soils in all the investigated sites were acidic soils in the pH range between 5 and 6.5. The complexity of the large data matrix obtained from the analysis was overcome by multivariate analytical methods to assist in evaluating the soils' ability to treat effluent and to understand the importance of various parameters. The analytical methods selected to serve this purpose were PROMETHEE and GAIA. The analysis indicated that the most suitable soils for effluent renovation are the Kandosols whilst the most unsatisfactory soil order was found to be Podosol. The GAIA analysis was in agreement with quantitative analysis conducted earlier. An extensive laboratory column study lasting almost one year was undertaken to validate the results of the data analysis from the field investigation. The main objectives of this experiment were to examine the soil behaviour under practical effluent application and to investigate the long-term acceptance rate for these soils. Twelve representative soils were selected for the column experiment from the previously investigated sites and undisturbed soil cores were collected for this purpose. The results from the column study matched closely with the evaluation conducted at the earlier stages of the research. Soil physico-chemical analysis before and after effluent application indicated that the soils' acidity was improved toward neutrality after effluent application. The results indicated that soils have a greater ability to handle phosphorus than nitrogen. The most favorable cation exchange capacity for soils to treat and transmit effluent was between 15 and 40 meq/100g. Based on the results of the column study, the long-term acceptance rate (LTAR) was determined for the investigated twelve soil types. Eleven out of twelve soils reported specific LTAR values between 0.18-0.22 cm/day. For the duration of the laboratory study, the Podosol order did not reach its LTAR value due to the extremely sandy nature of the soil. The time required to achieve LTAR varied between different soils from 40 to 330 days. The outcomes of this research was integrated into a soil suitability map for on-site sewage treatment systems for Logan City Council. This will assist the authorities in providing sustainable solutions for on-site systems failure.
15

Mobil slamavvattning med polymer : Jämförelse av avloppsvattens partikelhalt beroende av tömningsmetod

Ramström, Emma January 2018 (has links)
The purpose of the study was to evaluate which method for emptying of septic tanks that contributed with the lowest particle content in outgoing water during the period of a year. The methods for emptying in the comparison was mobile dewatering using polymer, complete pump-out and mobile dewatering using mechanic separation. Within the study, wastewater was sampled from septic tanks third compartment, however, only from septic tanks that were dewatered using polymer. Samples were taken one time before emptying followed by five occasions after emptying. The results from those samples were compared to previously existing results from complete pump-out and mobile dewatering using mechanic separation. Due to differences in method for sampling, the comparison in the discussion was limited to; samples taken before emptying and two weeks after emptying from septic tanks that had been completely pumped-out and dewatered using mechanic separation. The samples taken before emptying showed the particle content after using the septic tanks for a year since the previous emptying. Based on those samples there were no significant difference between mobile dewatering using polymer and complete pump-out or between mobile dewatering using polymer and mobile dewatering using mechanic separation. Two weeks after emptying the lowest particle contents were found in septic tanks that had been completely pumped-out followed by the two dewatering methods.
16

Diagnóstico e avaliação de coleta e disposição de lodo de fossa e de tanque séptico em Cuiabá - MT

Ramos, Lediane Léslie Campos 27 February 2014 (has links)
Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2017-10-13T15:14:41Z No. of bitstreams: 1 DISS_2014_Lediane Leslie Campos Ramos.pdf: 3409711 bytes, checksum: 0b979d9b033509b0f053399204bcbcc1 (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-11-07T10:27:32Z (GMT) No. of bitstreams: 1 DISS_2014_Lediane Leslie Campos Ramos.pdf: 3409711 bytes, checksum: 0b979d9b033509b0f053399204bcbcc1 (MD5) / Made available in DSpace on 2017-11-07T10:27:32Z (GMT). No. of bitstreams: 1 DISS_2014_Lediane Leslie Campos Ramos.pdf: 3409711 bytes, checksum: 0b979d9b033509b0f053399204bcbcc1 (MD5) Previous issue date: 2014-02-27 / Devido a precariedade e a falta de rede pública coletora de esgoto na cidade de Cuiabá é grande a procura por serviços das empresas de limpa fossa, o que torna-se um problema, dado que o lodo gerado pelos sistemas de fossas sépticas comporta concentrações expressivas de nutrientes, matéria orgânica, poluentes inorgânicos e organismos patogênicos. O presente estudo tem como objetivo o diagnostico e avaliação da destinação final do lodo de fossa e de tanque séptico em Cuiabá/MT, e propor medidas de adequação de tratamento. Para isso, foram realizadas entrevistas junto às empresas prestadoras deste serviço, e levantamentos junto à Estação de Tratamento de Esgoto Tijucal (ETE Tijucal). A estação é composta por tratamento preliminar (caixa de areia, gradeamento e calha Parshall), dois reatores UASB, uma lagoa anaeróbia, seguida por duas lagoas facultativas em paralelo, e uma lagoa de maturação. Sua capacidade atual de tratamento é de 50 L/s, mas recebe uma vazão diária de 56,23 L/s. Levantamentos realizados neste trabalho indica que a vazão recebida diariamente pode ser maior que a apresentada pela Empresa responsável pela administração da ETE. Além da quantificação do volume de lodo lançado diariamente foi realizado a caracterização com determinação dos seguintes parâmetros: pH, Temperatura, Alcalinidade, Sólidos totais, Sólidos voláteis totais, Sólidos fixos, Sólidos sedimentáveis, Óleos e graxas, DBO, DQO, Fósforo total, Nitrogênio Kjeldahl. De acordo com o resultado da caracterização e comparação com estudos realizados nesta linha de pesquisa identificou-se um possível sistema de tratamento para o lodo de fossas e tanques sépticos. / Due to insecurity and lack of public collector sewer in the city of Cuiabá is great demand for the services of clean fossa companies, which becomes a problem, since the sludge generated by septic tank systems entails significant concentrations of nutrients, organic matter, inorganic pollutants and pathogenic organisms. The present study aims at the diagnosis and evaluation of the final destination of the sludge pit and septic tank in Cuiabá / MT, and proposes measures of adequacy of treatment. For this survey interviews were held with the companies providing this service, and with the Tijucal Sewage Treatment Station (ETE Tijucal). The station consists of preliminary treatment (sandbox, railing and Parshall), two UASB, anaerobic pond, facultative pond followed by two in parallel, and a maturation pond. Your current treatment capacity is 50 L / s, but receives a daily flow of 56.23 L / s. Surveys conducted in this paper indicates that the daily flow received may be higher than that presented by the company responsible for the management of ETE. Besides quantifying the volume of sludge released daily characterization was carried out by determining the following parameters: pH, temperature, alkalinity, total Total solids, volatile solids, fixed solids, settleable solids, oils and grease, BOD, COD, Total Phosphorus, Nitrogen Kjeldahl. According to the results of the characterization and comparison with studies conducted in this research identified a possible treatment system for the sludge pits and septic tanks.
17

Avaliação do desempenho da modificação de um sistema de tratamento de esgoto composto por tanque séptico e filtro anaeróbio por um modelo de aeração compartimentada / Performance evaluation of the modification of a sewage treatment system consisting of septic tank and anaerobic filter for a model compartimentalized aeration

França, Josue Tadeu Leite 20 August 2018 (has links)
Orientador: Ronaldo Stefanutti / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-20T00:18:11Z (GMT). No. of bitstreams: 1 Franca_JosueTadeuLeite_D.pdf: 5624209 bytes, checksum: 5cf73703ce197d3837470af4dd88e602 (MD5) Previous issue date: 2012 / Resumo: Este trabalho tem como objetivo avaliar o desempenho da modificação concernente a um processo de tratamento "tanque séptico seguido de filtro anaeróbio", no Distrito Bom Retiro, município de Angatuba, região sudoeste do Estado de São Paulo, por um modelo aerado, com aproveitamento integral das unidades existentes após pequenas adequações, visando atender a legislação e com baixo nível de operação. O sistema foi baseado em alguns parâmetros utilizados em lagoas aeradas e parcialmente aeradas. A remoção do lodo para a proposta é anual ou quando o sistema atingir os limites dos parâmetros de controle operacional: DBO efluente ? 60 mg O2 L-1 ou eficiência de remoção dos SST ? 80%. Após um ano de operação da proposta parcialmente concluída (sem tratamento preliminar), apesar de não atingir os limites máximos estabelecidos foram realizadas a quantificação e remoção do lodo gerado. O sistema de desaguamento foi realizado em uma série de "BAGs" verticais de polipropileno reutilizáveis por até 20 vezes, com capacidade para 2m³. Após as adequações, os resultados na segunda etapa do experimento com relação à DBO afluente e efluente, sólidos em suspensão total efluente (SST), residual de oxigênio dissolvido na saída do tanque de polimento, densidade de potência utilizada, custo de energia per capta (kWh ano-1) e custo de implantação per capta foram: DBO afluente e efluente teve como média e desvio padrão 674 ± 137 mg O2 L-1 e 22 ± 5 mg O2 L-1, respectivamente. A média aparada com relação ao residual de oxigênio dissolvido foi de 3,6 ± 1,2 mg L-1, a densidade de potência 42 W m-3, o consumo de energia foi de 56 kWh hab-1 ano-1 e o custo de implantação per capita foi de R$ 140,00. A proposta visa a adequação dos sistemas (tanque séptico + filtro anaeróbio) e implantação em pequenas comunidades, sem sistemas de tratamento de esgotos / Abstract: This work aims to evaluate the performance concerning the modification of the a treatment process "septic tank followed by anaerobic filter", in Bom Retiro district, municipality of Angatuba, and southwest of São Paulo, by aerated model with full use of existing units after minor adjustments, to meet the rules environmental and low level of operation. The system is based on some parameters used in aerated lagoons and partly aerated lagoons. The sludge removal is proposed for the year or when the system reaches the limits of the parameters of operational control: ? 60 mg O2 L-1 BOD effluent and TSS removal efficiency of ? 80%. After a year of operation of the proposed partially completed (without pre-treatment) did not reach the ceilings was conducted to quantify and removal of sludge generated. The dewatering system was conducted in a number of "BAGs" vertical polypropylene reusable for up to 20 times, with a capacity of 2 m³. After the adjustments results in the second stage of the experiment with respect to the influent and effluent BOD, total suspended solids effluent (TSS), residual dissolved oxygen in the tank outlet polishing, power density used, energy cost per capita (kWh year -1) and cost of deployment per capita were: influent and effluent BOD was mean and standard deviation 674 ± 137 mg O2 L-1 and 22 ± 5 mg O2 L-1, respectively. The mean residual trimmed with respect to dissolved oxygen was 3.6 ± 1,2 mg L-1, the power density 42 W m-3, the power consumption was 56 kWh. hab-1 year -1 and implementation cost per capita of R$ 140.00. The proposal aims adequacy of systems (septic tank + anaerobic filter) and deployment in small communities without sewage treatment systems / Doutorado / Saneamento e Ambiente / Doutor em Engenharia Civil
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Assessment and Modeling of Three Decentralized Resource Recovery Systems in the Cayes of the Belize Barrier Reef

Kalivoda, Mark D. 27 June 2017 (has links)
Three wastewater treatment systems (WWTS) situated on Cayes in the Belize Barrier Reef System were assessed in terms of the unique public health and environmental circumstances of being a tourist destination surrounded by fragile coral reef. Laughing Bird Caye, Silk Caye, and Little Water Caye are three small cayes that are the staging points for local diving, fishing, and other recreational tourism. All three systems are based upon pour-flush toilets, semi-anaerobic biodigesters and drainage fields. Limitations in cost, available resources, useable area, high infiltration rates of the sand, and salinity of the water have played a major factor in the construction and performance of the WWTS on the Cayes. This thesis aims to form an understanding of treatment efficiency of the WWTS, investigate the effectiveness of decentralized saltwater-based WWTS in comparison to freshwater-based WWTS, and provide recommendations to improve the performance and resource recovery in a manner appropriate for the context in which the systems are deployed. A mathematical model was developed to predict the performance of the WWTS based on available operational and water-quality input data. The model is based on the mass balances of six species: inert solids, fecal solids, bacterial biomass, soluble substrate (i.e. dissolved organic carbon), ammonium and nitrate. Effects of salinity were estimated for the two saltwater-based WWTS. The model predicted the effluent concentrations of fecal solids, soluble biological oxygen demand (BOD), ammonium, and nitrate. A sensitivity analysis was also performed on the predicted effluent treatment efficiency based upon influent load, oxygen concentration and system salinity. Results from Silk Caye and Laughing Bird Caye indicate that varying the number of visitors from seasonal lows to highs has a moderate impact on the effluent fecal solids and soluble BOD in the effluent. Due to the relatively large volume of the WWTS at Little Water Caye, and thus high HRT, varying the number of visitors did not have a significant effect. The model predicted a reduction of nitrogen from the effluent due to settled solids and the assimilation of the nitrogen into bacteria. However the model consistently projected an effluent nitrate concentration (as mg/L as N) between 60 and 63 across the three WWTS. The oxygen concentration within the WWTS had the greatest effect on effluent BOD of the three parameters tested in the sensitivity analysis. Results from the sensitivity analysis indicate that a minimum concentration of 0.95 mg/L of oxygen is required before the model can accurately predict the effluent BOD concentration. The concentration of effluent fecal solids did not significantly change with changes in oxygen concentration. Salinity had a significant effect on the predicted fecal solids and soluble BOD in the effluent. Predicted fecal solids in the effluent wastewater increased approximately 60 percent from freshwater conditions to 4 percent salinity. Similarly, effluent BOD concentration increased strongly with increasing salinity. The increase in concentration is due to the major reduction of substrate-consuming bacteria by cell-die-off. The model predicts that a significant increase in cell die-off begins to occur at 2.4 percent salinity. The predicted effluent of the freshwater-based WWTS on Little Water Caye was compared to 166 wastewater treatment plants operating in Brazil. Comparison between the WWTS on the Caye and the decentralized WWTS in Brazil indicate that the predicted removal efficiencies of total suspended solids and soluble BOD are higher than the measured efficiencies of the WWTS. However, the total nitrogen removal efficiency for the WWTS on the Caye was the least effective; most-likely because the model does not account for denitrification within the biodigester. The comparison between the WWTS illustrates that the predicted removal efficiency of BOD and TSS solids is most likely less in the actual measurement than predicted value from the model. The WWTS on the Cayes were constructed to mitigate the impacts of the wastewater produced by visitors on the general health of the pubic and the environment. Considering the reports of the eutrophication affecting the coral reefs surrounding the Cayes, the WWTS have largely failed in at least one aspect of their purpose. The effluent water quality predicted by the model also suggests that significant concentrations of nitrogen are entering the surrounding ocean habitat as ammonia and nitrate. Recommendations to improve the effluent wastewater quality were separated into three categories based upon the required level of input to realize the recommendation. The input includes the capital cost and labor of the change, the level of buy-in from the users of the system, and the resulting maintenance requirements. The implementation of a urine separation toilet system was proposed as a method to reduce effluent nitrogen entering the environment and to create a resource recovery system (RR) from the already constructed WWTS.
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Study on household wastewater characterization and septic tanks' function in urban areas of Vietnam / ベトナム都市部における家庭排水の特性および腐敗槽の機能に関する研究

Pham Nguyet Anh 24 September 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第18629号 / 地環博第124号 / 新制||地環||25(附属図書館) / 31529 / 京都大学大学院地球環境学舎環境マネジメント専攻 / (主査)教授 藤井 滋穂, 教授 高岡 昌輝, 准教授 田中 周平 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM
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Fate Of Nitrogen And Phosphorus Species From A Black And Goldtm Nugget Mix In A Laboratoy Column Simulated Septic Tank Drainfiel

Shah, Timir 01 January 2007 (has links)
The presence of nitrates and phosphorus in ground water is a worldwide problem. A septic tank with drainfield that is conventionally designed does not typically remove nitrogen in the form of nitrates. The main risks are in "Blue baby" syndrome and suspected carcinogenic effect of nitrates on humans and the nutrient enrichment of receiving waters. In some areas nitrate and phosphorus removal are essentially required. Thus the information in this report concentrates on using media in the drainfield for the removal of nitrogen and phosphorus. Extensive work has been conducted in the past few decades in order to find suitable media for denitrification with high selectivity towards nitrogen. Column experiments were conducted at the University of Central Florida to simulate the actual septic tank drainfield using mixes of fine sand. In one of the columns Sawdust and Tire Crumb were added to the Sand (STS) and in the other column Paper and Tire Crumb were added to the Sand (STP). Tire crumb was added as a carbon source required for better denitrification and for sorption. The columns were dosed daily using regular septic tank effluent and it was a continuous batch system. Samples were taken after a hydraulic retention time (HRT) of 24 hours and comparisons were made of the effluent with the influent to show percentage removal of nitrogen (nitrates, ammonia and total nitrogen), phosphorus (ortho-phosphorus and total phosphorus) and BOD. STS and STP columns showed more than 90% removal for all parameters (nitrates, ammonia, total nitrogen, ortho-phosphorus, total phosphorus, BOD). The results indicate that the investigated media blend (Black and GoldTM Nugget Mix) has the potential for successful application in full scale operations. It is recommended that Black and GoldTM Nugget Mix be used to achieve the required removal of the nutrients.

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