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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

Co-utilisation of microalgae for wastewater treatment and the production of animal feed supplements

Johnson, Hailey E January 2011 (has links)
Microalgae have a variety of commercial applications, the oldest of which include utilisation as a food source and for use in wastewater treatment. These applications, however, are seldom combined due to toxicity concerns, for ethical reasons, and generally the requirement for cultivation of a single algae species for use as a feed supplement. These problems might be negated if a “safer” wastewater such as that from agricultural and/or commercial food production facilities were to be utilised and if a stable algae population can be maintained. In this investigation preliminary studies were carried out using an Integrated Algae Pond System (IAPS) for domestic wastewater treatment to determine the species composition in the associated High Rate Algae Ponds (HRAPs). The effect of different modes of operation, continuous versus batch, on nutrient removal, productivity and species composition was also investigated. Furthermore, indigenous species in the HRAP were isolated and molecularly identified as, Chlorella, Micractinium, Scenedesmus and Pediastrum. Additionally, the effect of the nor amino acid, 2-hydroxy-4-(methylthio)-butanoic acid (HMTBA) and its Cu-chelated derivative, on the growth and biochemical composition of Chlorella, Micractinium, Scenedesmus, Pediastrum and Spirulina was investigated. Species composition in the HRAP was stable under continuous operation with Micractinium dominating > 90% of the algae population. Under batch operation the population dynamic shifted; Chlorella outcompeted Micractinium possibly due to nutrient depletion and selective grazing pressures caused by proliferation of Daphnia. Higher species diversity was observed during batch mode as slower growing algae were able to establish in the HRAP. Nutrient removal efficiency and biomass productivity was higher in continuous mode, however lower nutrient levels were obtained in batch operation. HMTBA did not significantly affect growth rate, however treatment with 10 mg.L-1 resulted in slightly increased growth rate in Micractinium and increased final biomass concentrations in Chlorella, Micractinium and Spirulina (although this was not statistically significant for Micractinium and Spirulina), which are known mixotrophic species. Algae treated with Cu-HMTBA, showed reduced final biomass concentration with 10 mg.L-1, caused by Cu toxicity. Biochemical composition of the algae was species-specific and differed through the growth cycle, with high protein observed during early growth and high carbohydrate during late growth/early stationary phase. Additionally, 0.1 mg.L-1 HMTBA and Cu-HMTBA significantly reduced protein content in Chlorella, Micractinium, Scenedesmus and Pediastrum. In conclusion, operation of the HRAP in continuous culture provided suitable wastewater treatment with high productivity of an ideal species, Micractinium, for use in animal feed supplementation. This species had 40% protein content during growth (higher than the other species tested) and dominated the HRAP at > 90% of the algae population during continuous mode. Addition of HMTBA (> 1 mg.L-1) to algae cultivation systems and those treating wastewater, has the potential to improve productivity and the value of the biomass by enhancing protein content. Overall, the co-utilisation of microalgae for wastewater treatment and the generation of a biomass rich in protein, for incorporation into formulated animal feed supplements, represents a closed ecosystem which conserves nutrients and regenerates a most valuable resource, water.
12

Biocoque de eucalipto como fonte de energia renovável para uso siderúrgico /

Barros, João Lúcio de January 2019 (has links)
Orientador: Leandro Cardoso de Morais / Resumo: O Brasil se destaca na produção do ferro e aço, e principalmente na utilização de fontes renováveis como insumos energéticos para sua produção. O biocoque possui potencial para utilização de biomassas como insumos energéticos em alto fornos, em substituição aos tradicionais combustíveis fósseis, carvão e coque, porém, ainda é um material pouco conhecido cientificamente. O objetivo foi encontrar os parâmetros adequados para a produção, em escala laboratorial, do biocoque de casca e serragem da madeira de eucalipto. Também verificar suas principais características térmicas e físico-químicas, antes e após a produção do biocoque. Foi usado a casca e serragem de eucalipto para a produção do biocoque. Os materiais passaram por analises de umidade, analise imediata, analise elementar, poder calorífico, densidades, resistência mecânica, estabilidade dimensional, termogravimetria, microscopia MEV, espectroscopia FTIR e EDS, difratometria de raio-x e análises cinética. O biocoque para ambos os materiais foram prensados com força de 10 toneladas sob 180 °C de temperatura por 10 minutos, apresentando características físico-químicas adequadas para o uso. Os biocoques tiveram caracteristicas físicas adequadas a necessidade de uso com alta resistência mecânica, com aproximadamente 10 MPa para ambos os materiais e durabilidade acima de 99 %. A densidade aparente (1.350 kg.m-3) foi aumentada aproximadamente cinco vezes comparado ao valor inicial para o material particulado. Os materiais apres... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
13

Avaliação de dois modelos de vermicompostagem para gerenciamento de resíduos orgânicos crus e aplicação como tema de educação ambiental no ensino formal / Evaluation of two models of vermicomposting aimed at the management and treatment of raw organic residues of vegetable origin and application as environmental education theme in formal education

Vaz, Ana Claudia Nüernberg 31 May 2017 (has links)
Do total de Resíduos Sólidos Urbanos gerados no Brasil, 51% são resíduos orgânicos dispostos em aterros sanitários ou lixões. A Política Nacional de Resíduos Sólidos integra as Políticas Nacionais do Meio Ambiente e da Educação Ambiental. Isso indica o reconhecimento do resíduo sólido reutilizável e reciclável como um bem econômico, de valor social, promotor de cidadania, gerador de trabalho e renda. O resíduo orgânico gerado na Universidade Tecnológica Federal do Paraná - UTFPR câmpus Curitiba, serviu como estudo de caso para avaliar o gerenciamento e tratamento de resíduos orgânicos utilizando a vermicompostagem e serviu como dinamizador da Educação Ambiental - EA para o ensino fundamental. Para o gerenciamento dos resíduos orgânicos em grande escala, como no Restaurante Universitário-RU da UTFPR, foi verificada a separação de resíduos na cozinha durante uma semana de resíduos crus, sobras do buffet e do prato. Os resíduos crus foram tratados em dois modelos de vermidigestores, um composto por caixas com o fundo modificado com furos e outro com barras. Os resíduos orgânicos crus mais gerados foram folhas de alface, repolho e cascas de pepino que formaram o substrato de alimento para os vermidigestores, e foram adicionados 10 kg de vermicomposto com 1,21 kg de minhocas da espécie Eisenia fetida por m2. O experimento foi planejado conduzido em 60 dias com uma aplicação de alimentação. A cada três dias foram retiradas amostras do vermicomposto e do lixiviado para analisar os seguintes parâmetros: temperatura; umidade; pH; quantidade de lixiviado; substâncias húmicas; coliformes; salmonella; relação C/N; macro e micronutrientes. Os resultados apresentaram temperatura média de 23ºC; a umidade média de 81%; o pH se manteve constante em 7,7; coliformes e salmonella foram encontrados abaixo do limite estabelecido e a relação média C/N no vermicomposto e do chorume foi de 10,8/1. A análise de micro e macro nutrientes indicou um fertilizante rico em nitrogênio e alta quantidade de ferro para os dois modelos. Observou-se que o modelo do vermidigestor com barras obteve melhor resultado quando avaliada a decomposição da matéria orgânica lábil, escoamento de lixiviado e reprodução da população de minhocas, sendo indicado para gerenciamento em grande escala. Para a aplicação em pequena escala, os dois modelos são adequados. A técnica da vermicompostagem foi aplicada em atividade de EA em escolas do ensino básico, as dificuldades e questionamentos dos professores, forneceram subsídios para o desenvolvimento de duas cartilhas: uma para o público infantil e outra para o público adulto. / Of the total urban solid waste generated in Brazil, 51% is organic waste disposed in landfills. The National Solid Waste Policy is part of the National Environmental Policy and articulates with the National Environmental Education Policy, and indicates the recognition of reusable and recyclable solid waste as an economic good, of social value, as a promoter of citizenship, a generator of jobs and income. The organic waste generated at the Federal Technology University of Paraná - UTFPR campus Curitiba, served as a case study to evaluate the management and treatment of organic waste using vermicomposting, which requires less space and serves as a promoter of Environmental Education - EE for teaching. For the management of large-scale organic waste, such as UTFPR University Restaurant-UR, the separation of residues in the kitchen was verified, the amount generated during a week of both raw and leftover waste from the buffet and dish. Two models of vermidigestors were used in duplicate, one consisting of boxes with the bottom modified with holes and another with bars. The most commonly generated raw organic residues were leaves of lettuce, cabbage and cucumber peels. Each of these vegetables was chopped separately to compose the food substrate, and to form the initial substrate that goes into the vermidigestores, 10 kg of humus were added with 1.21 kg of earthworms othe species Eisenia fétida per m2. The experiment was conducted in 60 days with only one feeding application. Samples of vermicompost and leachate were collected every three days to analyze the parameters temperature, humidity, pH, amount of leachate, humic substances, Coliforms, Salmonella, C / N ratio, macro and micronutrients. The results presented average temperature of 23ºC; The average humidity of 81%; The pH remained constant at 7.7; Coliforms and Salmonella were found below the established limit, and the mean C / N ratio in vermicompost and manure was 10.8 / 1. The analysis of micro and macro nutrients indicated a fertilizer rich in nitrogen and high amount of iron for both models. It was observed that the model of vermidigestor with bars obtained better result when evaluating the decomposition of the labile organic matter, leachate flow and reproduction of the earthworm population, being this model the one indicated for large scale management. For small scale application the two models are suitable. The box vermicomposting technique was applied in the EE activity from a primary school, identifying the difficulties and questions of the teachers, provided subsidies for the development of two booklets, one for the infantile public and another one for the adult public.
14

Avaliação de dois modelos de vermicompostagem para gerenciamento de resíduos orgânicos crus e aplicação como tema de educação ambiental no ensino formal / Evaluation of two models of vermicomposting aimed at the management and treatment of raw organic residues of vegetable origin and application as environmental education theme in formal education

Vaz, Ana Claudia Nüernberg 31 May 2017 (has links)
Do total de Resíduos Sólidos Urbanos gerados no Brasil, 51% são resíduos orgânicos dispostos em aterros sanitários ou lixões. A Política Nacional de Resíduos Sólidos integra as Políticas Nacionais do Meio Ambiente e da Educação Ambiental. Isso indica o reconhecimento do resíduo sólido reutilizável e reciclável como um bem econômico, de valor social, promotor de cidadania, gerador de trabalho e renda. O resíduo orgânico gerado na Universidade Tecnológica Federal do Paraná - UTFPR câmpus Curitiba, serviu como estudo de caso para avaliar o gerenciamento e tratamento de resíduos orgânicos utilizando a vermicompostagem e serviu como dinamizador da Educação Ambiental - EA para o ensino fundamental. Para o gerenciamento dos resíduos orgânicos em grande escala, como no Restaurante Universitário-RU da UTFPR, foi verificada a separação de resíduos na cozinha durante uma semana de resíduos crus, sobras do buffet e do prato. Os resíduos crus foram tratados em dois modelos de vermidigestores, um composto por caixas com o fundo modificado com furos e outro com barras. Os resíduos orgânicos crus mais gerados foram folhas de alface, repolho e cascas de pepino que formaram o substrato de alimento para os vermidigestores, e foram adicionados 10 kg de vermicomposto com 1,21 kg de minhocas da espécie Eisenia fetida por m2. O experimento foi planejado conduzido em 60 dias com uma aplicação de alimentação. A cada três dias foram retiradas amostras do vermicomposto e do lixiviado para analisar os seguintes parâmetros: temperatura; umidade; pH; quantidade de lixiviado; substâncias húmicas; coliformes; salmonella; relação C/N; macro e micronutrientes. Os resultados apresentaram temperatura média de 23ºC; a umidade média de 81%; o pH se manteve constante em 7,7; coliformes e salmonella foram encontrados abaixo do limite estabelecido e a relação média C/N no vermicomposto e do chorume foi de 10,8/1. A análise de micro e macro nutrientes indicou um fertilizante rico em nitrogênio e alta quantidade de ferro para os dois modelos. Observou-se que o modelo do vermidigestor com barras obteve melhor resultado quando avaliada a decomposição da matéria orgânica lábil, escoamento de lixiviado e reprodução da população de minhocas, sendo indicado para gerenciamento em grande escala. Para a aplicação em pequena escala, os dois modelos são adequados. A técnica da vermicompostagem foi aplicada em atividade de EA em escolas do ensino básico, as dificuldades e questionamentos dos professores, forneceram subsídios para o desenvolvimento de duas cartilhas: uma para o público infantil e outra para o público adulto. / Of the total urban solid waste generated in Brazil, 51% is organic waste disposed in landfills. The National Solid Waste Policy is part of the National Environmental Policy and articulates with the National Environmental Education Policy, and indicates the recognition of reusable and recyclable solid waste as an economic good, of social value, as a promoter of citizenship, a generator of jobs and income. The organic waste generated at the Federal Technology University of Paraná - UTFPR campus Curitiba, served as a case study to evaluate the management and treatment of organic waste using vermicomposting, which requires less space and serves as a promoter of Environmental Education - EE for teaching. For the management of large-scale organic waste, such as UTFPR University Restaurant-UR, the separation of residues in the kitchen was verified, the amount generated during a week of both raw and leftover waste from the buffet and dish. Two models of vermidigestors were used in duplicate, one consisting of boxes with the bottom modified with holes and another with bars. The most commonly generated raw organic residues were leaves of lettuce, cabbage and cucumber peels. Each of these vegetables was chopped separately to compose the food substrate, and to form the initial substrate that goes into the vermidigestores, 10 kg of humus were added with 1.21 kg of earthworms othe species Eisenia fétida per m2. The experiment was conducted in 60 days with only one feeding application. Samples of vermicompost and leachate were collected every three days to analyze the parameters temperature, humidity, pH, amount of leachate, humic substances, Coliforms, Salmonella, C / N ratio, macro and micronutrients. The results presented average temperature of 23ºC; The average humidity of 81%; The pH remained constant at 7.7; Coliforms and Salmonella were found below the established limit, and the mean C / N ratio in vermicompost and manure was 10.8 / 1. The analysis of micro and macro nutrients indicated a fertilizer rich in nitrogen and high amount of iron for both models. It was observed that the model of vermidigestor with bars obtained better result when evaluating the decomposition of the labile organic matter, leachate flow and reproduction of the earthworm population, being this model the one indicated for large scale management. For small scale application the two models are suitable. The box vermicomposting technique was applied in the EE activity from a primary school, identifying the difficulties and questions of the teachers, provided subsidies for the development of two booklets, one for the infantile public and another one for the adult public.
15

Restoring degraded soils with organic matter: a case study of the restoration process in macadamia orchards, Limpopo Province

Nonyana, Thambulo Aubrey 05 August 2015 (has links)
MENVSC / Department of Environmental Sciences

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