Made available in DSpace on 2014-06-11T19:31:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-09-25Bitstream added on 2014-06-13T20:21:42Z : No. of bitstreams: 1 camara_ft_dr_jabo.pdf: 548163 bytes, checksum: a7f77b0a81b4b0e6e9ac1c242bc53422 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Funep / Biodiesel is a renewable fuel, biodegradable and produced from vegetable oil or from animal fat through transesterification. The viability of this product as a source of alternative energy depends on various factors, among which the mixture proportion and the stability during storage time stand out. This is because the availability of the raw material is seasonal and varies in accordance with the harvests of different cultures. The objective of the present work was to evaluate the operational performance of an agricultural tractor working with palm oil biodiesel while performing the operation of tillage with a chisel plow, also opacity, the density of the fuel and the outflow from the filling pump were studied regarding storage time and biodiesel/diesel mixture proportion. The experiment was conducted in the Department of Rural Engineering at UNESP, Jaboticabal, Brazil, in partnership with LADETEL/USP-Ribeirão Preto. Storage time was with new fuel (soon after production), three months and six months, and the percentage proportions used for biodiesel + diesel were B0 (0+100), B5 (5+95), B50 (50+50) e B100 (100+0). When comparing the treatments, we evaluated the fuel consumption, the real velocity of displacement, the sliding of the wheels, the strength of the traction bar, the fuel density, the outflow from the filling pump and the opacity of the fuel smoke. The results show an increase in consumption specific to a mixture starting from 25% biodiesel, although the storage time did not affect consumption. In relation to the opacity of smoke, there was a reduction, even with only 5% biodiesel in the mixture, again with the storage time having no influence.

Submitted by Cristiane Chim (cristiane.chim@ucpel.edu.br) on 2018-12-03T10:42:25Z No. of bitstreams: 1 Patrique.pdf: 3054329 bytes, checksum: aa18d3c8b8679fb997de53a96a88b58a (MD5) / Made available in DSpace on 2018-12-03T10:42:25Z (GMT). No. of bitstreams: 1 Patrique.pdf: 3054329 bytes, checksum: aa18d3c8b8679fb997de53a96a88b58a (MD5) Previous issue date: 2018-10-16 / This work aims to evaluate the injection of HHO gas, from a hydrogen generator (electrolyser), into a diesel generator set. After mixing the HHO gas together with the diesel oil, a compression in exhaust gases, exhaust temperature, carbon monoxide emission, carbon dioxide and primary engine fuel consumption. The results allowed to evaluate that, when the engine was fed with diesel and hydrogen, there was a better performance in relation to the burning of fuel, when compared to a feed only with the primary fuel. At constant rated speed, the results allowed us to conclude that the engine consumes a smaller amount of diesel fuel and generating less pollutant gases (monoxide and carbon dioxide) using the HHO gas injection. / Este trabalho tem por objetivo avaliar a injeção de gás HHO, proveniente de um gerador de hidrogênio (eletrolisador), em um grupo gerador à diesel. Após a mistura do gás HHO, juntamente com o óleo diesel, foram verificados e comparados nos gases de exaustão, a temperatura do escape, emissão de monóxido de carbono, dióxido de carbono e consumo de combustível primário do motor. Os resultados encontrados permitiram avaliar que, quando o motor foi alimentado com diesel e hidrogênio, houve melhor desempenho, em relação à queima de combustível, se comparado a uma alimentação apenas com o combustível primário. Com velocidade nominal constante, os resultados permitiram concluir que o motor consome menor quantidade de óleo diesel e gerando menos quantidade de gases poluentes (monóxido e dióxido de carbono) usando a injeção de gás HHO.

Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2016-11-18T15:46:08Z No. of bitstreams: 1 BlakeCDM_TESE.pdf: 4892316 bytes, checksum: 86d0db1f3948e83dab7334504ce8a41f (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-01-24T14:47:05Z (GMT) No. of bitstreams: 1 BlakeCDM_TESE.pdf: 4892316 bytes, checksum: 86d0db1f3948e83dab7334504ce8a41f (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-02-15T15:00:01Z (GMT) No. of bitstreams: 1 BlakeCDM_TESE.pdf: 4892316 bytes, checksum: 86d0db1f3948e83dab7334504ce8a41f (MD5) / Made available in DSpace on 2017-03-21T15:06:41Z (GMT). No. of bitstreams: 1 BlakeCDM_TESE.pdf: 4892316 bytes, checksum: 86d0db1f3948e83dab7334504ce8a41f (MD5) Previous issue date: 2016-02-29 / The residual oil frying (ORF), when disposed of incorrectly, cause negative impacts on the environment. However, its use as biofuel, generates great benefits of social, economic and environmental order. The objective of this study was to evaluate the performance of a group cycle diesel engine-generator powered by diesel and mineral diesel blends with residual oil frying. The trials were conducted in machines Instrumentation Laboratory and Agricultural Mechanization (Limma) of the Federal Rural University of the Semi-Arid (UFERSA) in Mossoró-RN, using a completely randomized design in factorial 4 x 5, with four replications. The treatments were diesel (DI) of oil and mixtures of diesel and residual oil frying (ORF) in the proportions: 50% DI and 50% ORF; DI 75% and 25% ORF; DI 90% and 10% ORF; 100% DI. The resistive loads used were 3, 6, 9, 12 and 15 kW. The engine oil temperature remains within the recommended operating range (85-95 ° C), indicating no lubricating oil contamination. All mixtures ORF had lower values for the exhaust temperature to the commercial diesel. The lower values of specific fuel consumption (EC) were obtained with higher loads, particularly at loads of 12 and 15 kW. The ORF25 mixture was the one with the lowest power generated and the EC farther diesel for all applied loads. Among the binary mixtures, ORF presented SE 10 similar to diesel in loads of 12 and 15 kW and the ORF50, the loads of 3, 9 and 12 kW; demonstrating that such mixing proportions, the ORF can replace mineral diesel / O óleo residual de fritura (ORF), quando descartado de maneira incorreta, causa impactos negativos ao meio ambiente. Todavia, a sua utilização como biocombustível gera grandes benefícios de ordem social, econômica e ambiental. Objetivou-se com este trabalho avaliar o desempenho de um grupo motor-gerador de ciclo diesel, alimentado com diesel mineral e misturas de diesel com óleo residual de frituras. Os ensaios foram conduzidos no Laboratório de Instrumentação de Máquinas e Mecanização Agrícola (LIMMA) da Universidade Federal Rural do Semi-Árido (UFERSA), em Mossoró-RN, utilizando delineamento experimental inteiramente casualizado, em esquema fatorial 4 x 5, com quatro repetições. Os tratamentos utilizados foram o óleo diesel mineral (DI) e misturas de diesel e óleo residual de fritura (ORF) nas proporções: 50% DI e 50% ORF; 75% DI e 25% ORF; 90% DI e 10% ORF; 100% DI. As cargas resistivas aplicadas foram de 3, 6, 9, 12 e 15 kW. A temperatura do óleo do motor se manteve dentro da faixa de trabalho recomendada (85-95 °C), indicativo de que não houve contaminação do óleo lubrificante. Todas as misturas de ORF apresentaram valores inferiores para temperatura de escapamento em relação ao diesel comercial. Os menores valores de consumo específico (CE) foram obtidos com as maiores cargas, sobretudo nas cargas de 12 e 15 kW. A mistura ORF25 foi a que apresentou a menor potência gerada e o CE mais distante do diesel para todas as cargas aplicadas. Dentre as misturas binárias, a ORF10 apresentou CE semelhante ao do diesel nas cargas de 12 e 15 kW, e a ORF50, nas cargas de 3, 9 e 12 kW; demonstrando que, nessas proporções de mistura, o ORF pode substituir o óleo diesel mineral / 2016-11-14

Orientador: Afonso Lopes / Banca: Wilson José Oliveira de Souza / Banca: Carlos Alberto Alves de Oliveira / Banca: Newton La Scala Junior / Banca: Carlos Eduardo Angeli Furlani / Resumo:Biodiesel é um combustível renovável, biodegradável e produzido a partir de óleo vegetal ou de gordura animal por meio de transesterificação. A viabilidade desse produto como fonte alternativa de energia depende de vários fatores, entre os quais se destacam a proporção de mistura e a estabilidade durante o período de armazenamento, uma vez que a disponibilidade de matéria-prima é sazonal e varia de acordo com a safra de cada cultura. O presente trabalho teve como objetivo avaliar o desempenho operacional realizando a operação de preparo do solo com escarificador e a opacidade da fumaça de um trator agrícola funcionando com biodiesel de dendê, a densidade do combustível e a vazão da bomba de abastecimento, cujos fatores estudados foram o tempo de armazenamento e a proporção de mistura biodiesel/diesel. O experimento foi conduzido no Departamento de Engenharia Rural, da UNESPJaboticabal, em parceria com o LADETEL/USP-Ribeirão Preto. O tempo de armazenamento foi combustível novo (logo após ser produzido), três e seis meses, e as proporções percentuais de biodiesel + diesel foram B0 (0+100), B5 (5+95), B50 (50+50) e B100 (100+0). Para comparar os tratamentos, foram avaliados o consumo de combustível, a força de tração na barra, a velocidade real de deslocamento, a patinagem das rodas, a potência na barra de tração, a densidade do combustível, a vazão da bomba de abastecimento e a opacidade da fumaça de combustão. Os resultados evidenciaram aumento no consumo específico a partir da mistura com 25% de biodiesel, entretanto o tempo de armazenamento não influenciou no consumo. Com relação a opacidade da fumaça, houve redução, mesmo com apenas 5% de biodiesel na mistura, com o tempo de armazenamento não influenciando. / Abstract: Biodiesel is a renewable fuel, biodegradable and produced from vegetable oil or from animal fat through transesterification. The viability of this product as a source of alternative energy depends on various factors, among which the mixture proportion and the stability during storage time stand out. This is because the availability of the raw material is seasonal and varies in accordance with the harvests of different cultures. The objective of the present work was to evaluate the operational performance of an agricultural tractor working with palm oil biodiesel while performing the operation of tillage with a chisel plow, also opacity, the density of the fuel and the outflow from the filling pump were studied regarding storage time and biodiesel/diesel mixture proportion. The experiment was conducted in the Department of Rural Engineering at UNESP, Jaboticabal, Brazil, in partnership with LADETEL/USP-Ribeirão Preto. Storage time was with new fuel (soon after production), three months and six months, and the percentage proportions used for biodiesel + diesel were B0 (0+100), B5 (5+95), B50 (50+50) e B100 (100+0). When comparing the treatments, we evaluated the fuel consumption, the real velocity of displacement, the sliding of the wheels, the strength of the traction bar, the fuel density, the outflow from the filling pump and the opacity of the fuel smoke. The results show an increase in consumption specific to a mixture starting from 25% biodiesel, although the storage time did not affect consumption. In relation to the opacity of smoke, there was a reduction, even with only 5% biodiesel in the mixture, again with the storage time having no influence. / Doutor

Biomass cookstoves are a significant source of various pollutants, such as CO2, CO, and particulate matter (PM). To mitigate the issues surrounding cookstoves, significant research has been undertaken on improved cookstoves (ICS). This research can be performed in a laboratory setting, in the field, or a combination of both. This work concentrates on the purely laboratory testing. Laboratory testing has both advantages and disadvantages when compared to field testing (e.g. decreased cost and increased consistency). However, field applications are variable, environments can be significantly different (for example wind and ambient temperature can be very different in the field vs. a controlled lab environment) and the personal preferences of the users of the cookstove can also be difficult to predict when only using laboratory testing. It is typically preferable to narrow down the possible cookstove choices by using laboratory results before heading to the field. This work concentrated on assessing the limitations of laboratory testing of cookstoves as presently constituted, as well as finding new ways to improve and expand upon the testing methodologies. Sources of error during testing was considered, leading to recommendations on how to adjust testing to decrease that error. Of note, it was found that higher thermal efficiencies led to increased propagated errors, which complicates the comparison of this efficiency among cookstoves. Additionally, a method for estimating the transient thermal efficiency was developed. Further, the effects of changing some of the key testing parameters were explored and the results showed that the overall thermal efficiency was minimally affected by parameter variations within the WBT or ISO 19867-1 guidelines. Finally, two methods were explored and compared for finding kinetic parameters associated with transforming food from the uncooked state to the cooked state. It was found that physical testing was more effective for samples that started in a harder physical state, whereas DSC testing was more effective with samples that had lower water content. This analysis was done with the intention of using transformation kinetics in future applications of cookstove models so that researchers could gain additional insights into which stoves may be best for their target market.

Orientador: Pedro Magalhães Sobrinho / Resumo: O aço é um dos materiais mais utilizados em todo o mundo, é possível ser 100% reciclado, obtendo novo aço sem perda de qualidade e quantas vezes for necessário. O setor siderúrgico é o maior consumidor de energia final destinado a indústria. Para produção do aço existem diversas alternativas possíveis. Neste trabalho é destacada a do forno elétrico a arco, a mais eficiente em termos de energia consumida e a única a qual pode-se utilizar como matéria-prima até 100% de material reciclado. Sendo o aço uma commodity, uma mercadoria básica facilmente intercambiável e utilizada como insumo para produção de outros produtos, tem seu preço regulado pelo mercado e trabalhos em eficiência energética são essenciais para a competitividade das empresas. O presente trabalho visa elaborar sugestões de métodos e tecnologias que possibilitem a redução do consumo específico de energia elétrica em kWh/t (quilowatt hora por tonelada de aço) para o processo de fusão do aço de um forno elétrico a arco, localizado na região do Vale do Paraíba. A metodologia empregada foi a pesquisa-ação, tendo um forno elétrico a arco real, disponível para estudos e captura de dados. As soluções encontradas estão desde técnicas operacionais de produção, até tecnologias em reaproveitamento de gases de exaustão, utilizados para o pré-aquecimento de sucata. Como resultado da pesquisa, obteve-se um conjunto de possibilidades tecnológicas com ganhos de até 143 kWh/t, o que representa cerca de 34% de redução no consumo es... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Steel is one of the most widely used materials worldwide, and it is possible to recycle 100% of it so as to generate new steels without quality loss and as many times as needed, however, the steel sector is the largest final energy consumer. There are several possible routes for steel production, but the Electric Arc Furnace has been selected for the present work due to being the most efficient in terms of energy consumption and it is the only one that can use up to 100% of recycled matter as raw material. As steel is a commodity, a basic goods easily interchangeable and used as input for the production of other products, its price is set by the market and energy efficiency studies are essential for the competitiveness of companies. The present work aims to elaborate suggestions of methods and technologies that allow the reduction of the specific electric energy consumption in kWh/t (kilowatt hour per ton of steel) by the steel melting process of an electric arc furnace located in the region of the Paraíba Valley. The methodology used was the action research, having an electric arc furnace, available for studies and data capture. The identified solutions range from operational production techniques to exhaust gas recovery technologies for scrap preheating. As a result, a set of technological possibilities with savings of up to 143 kWh/t have been obtained, which represents about 34% reduction in specific electric energy consumption by taking into account an average consumptio... (Complete abstract click electronic access below) / Mestre