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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.
291

Purifica??o e performance da reutiliza??o do Magnesol usado na purifica??o de biodiesel como proposta de diminui??o dos custos do processo / Purification and performance of the reuse of Magnesol used in the biodiesel purification Process as a proposed decrease in the costs of the process

Coelho, Bruna Naidon 15 July 2016 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-09-26T12:25:36Z No. of bitstreams: 1 DIS_BRUNA_NAIDON_COELHO_COMPLETO.pdf: 3029478 bytes, checksum: 99a39c350f40679d8ddd27a67ef8cef7 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-09-26T12:25:44Z (GMT) No. of bitstreams: 1 DIS_BRUNA_NAIDON_COELHO_COMPLETO.pdf: 3029478 bytes, checksum: 99a39c350f40679d8ddd27a67ef8cef7 (MD5) / Made available in DSpace on 2017-09-26T12:26:02Z (GMT). No. of bitstreams: 1 DIS_BRUNA_NAIDON_COELHO_COMPLETO.pdf: 3029478 bytes, checksum: 99a39c350f40679d8ddd27a67ef8cef7 (MD5) Previous issue date: 2016-07-15 / New searches for technologies that allow to obtain fuels with the same efficiency of fossil fuels, however, with renewable raw material are increasingly on the agenda in the current world scenario. Biodiesel, derived from vegetable or animal oils, fits perfectly in this context, above all, biodiesel from frying oil that still brings to the surface the resolution of a major environmental problem: the incorrect disposal of oils that are harmful to the environment. However, in its transesterification, some undesirable by-products are found that can to cause problems in the automobile engine. For resolt this problem requires the purification of this biofuel. Purification can be obtented by two routes: wet and dry, the wet being most commonly used in industry. In this type of purification where the water is used for the washing of biodiesel, after purification, this contaminated water also entails another environmental problem: a highly polluted effluent. On the other hand, the dry purification makes use of an adsorbent that generates less effluent and, after use, is usually grounded by its users. In this work studed the recovery of an adsorbent that has been widely used, the Magnesol, and him reuse has been studied for cost reduction purposes in the biodiesel purification process. After the creation of the methodology of recuperation of Magnesol, some solvents were tested and, with the elemental analysis of Carbon, it was verified which solvent presented better performance in the adsorbent recovery, being THF the highlight of this work. The analysis of FTIR, TGA and MEV showed that the adsorbent recovery was efficient, and the chromatography analysis showed that the performance of biodiesel purification with recovered Magnesol should be more worked so that it can be more efficient as it is when used virgin. / Novas procuras por tecnologias que permitam obter-se combust?veis com a mesma efici?ncia dos combust?veis f?sseis, por?m, com mat?ria prima renov?vel est?o cada vez mais em pauta no cen?rio mundial. O biodiesel, proveniente de ?leos vegetais ou animais, encaixa-se perfeitamente neste contexto, sobretudo, o biodiesel proveniente de ?leo de fritura que ainda traz ? tona a resolu??o de um grande problema ambiental: o despejo incorreto de ?leos que s?o prejudiciais ao meio ambiente. Por?m, em sua transesterifica??o, s?o encontrados alguns subprodutos indesej?veis e que podem acarretar problemas no motor do autom?vel, sendo necess?ria a purifica??o deste biocombust?vel. A purifica??o pode ser realizada por duas vias: ?mida e seca, sendo a ?mida mais comumente utilizada na ind?stria. Neste tipo de purifica??o ? utilizado ?gua para a lavagem do biodiesel e, ap?s a purifica??o, esta ?gua contaminada tamb?m acarreta em outro problema ambiental: um efluente altamente polu?do. A purifica??o via seca faz a utiliza??o de um adsorvente que gera menos efluentes e, ap?s sua utiliza??o, costuma ser descartado em aterros sanit?rios pelos seus usu?rios. Neste trabalho foi estudado a recupera??o de um adsorvente que vem sendo muito utilizado, o Magnesol, bem como, sua reutiliza??o, para fins de redu??o de custos no processo de purifica??o do biodiesel. Ap?s a cria??o da metodologia de recupera??o do Magnesol, alguns solventes foram testados e, com a an?lise elementar de carbono, foi verificado qual solvente apresentou melhor performance na recupera??o do adsorvente, sendo THF o destaque deste trabalho. As an?lises de FTIR, TGA e MEV mostraram que a recupera??o do adsorvente foi eficiente, j? a an?lise de cromatografia gasosa mostrou que o desempenho da purifica??o do biodiesel com Magnesol recuperado dever? ser mais trabalhada para que o mesmo possa ser mais eficiente tal qual quando utilizado ainda virgem.
292

Caracterização química de frações líquidas obtidas a partir do craqueamento térmico de resíduo gorduroso /

França, Angela Patricia, 1983-, Simionatto, Edésio Luiz, 1962-, Universidade Regional de Blumenau. Programa de Pós-Graduação em Química. January 2014 (has links) (PDF)
Orientador: Edesio Luiz Simionatto. / Dissertação (mestrado) - Universidade Regional Blumenau, Centro de Ciências Exatas e Naturais, Programa de Pós-Graduação em Química.
293

Catalytic monoliths for biodiesel production

Asli, Umi A. January 2011 (has links)
Although the transesterification reaction of triglycerides with alcohols is well known and practiced on a commercial scale (using acid or alkaline catalysts), there is plenty of scope to improve this process. One approach involves the use of heterogeneous catalysts that could be retained in a fixed bed, and this would enable a continuous process to be developed. With this aim in mind, zinc proline (Zn(C5H8NO2)2) was used as a catalyst, which was coated onto a cordierite monolith support (62 cells/cm2). Two different coating methods were explored, and SEM images of the surface revealed interesting crystal structures on the surface of the cordierite. Experiments were then performed in a batch reactor (120 ml) to assess the activity of the catalyst (molar ratio methanol:rapeseed oil = 12:1, T = 195ºC and P = 20 bar, 2 h duration). Although high conversions could be achieved, the catalyst was found to lose activity with time, and even the cordierite support was also found to be catalytically active. These aspects were explored further, in a continuous flow reactor, which had an i.d. = 6.2 mm, and multiple heated sections (500 mm each) into which pieces (10 mm long) of catalyst coated monoliths were inserted. Experiments were performed with packed lengths of 200 and 400 mm, and with liquid flows ranging from 0.1 to 2.9 ml min-1. Although it was shown that high conversions can be achieved over extended run-times (e.g. 100 to 200 min), it was clear that the catalyst was losing its activity. Measurements also showed, that during the course of an experiment, Zn was leaching, and this clearly contributed to catalyst deactivation Despite the loss in activity of the zinc proline catalyst, the reaction system developed in this thesis was shown to work well, and that it could be used to evaluate the performance of catalytically coated sections of monolith. To demonstrate the use of this system, a few scoping studies were also performed using SrO as a catalyst, which was coated onto the cordierite monolith.
294

Biodeterioração de misturas de diesel e biodiesel e seu controle com biocidas / Biodeterioration of diesel and biodiesel blends and its control with biocide

Bücker, Francielle January 2009 (has links)
Durante o armazenamento, as vantagens do biodiesel tais como a biodegradabilidade, a afinidade pela água e a ausência de aromáticos, podem tornar o combustível ainda mais suscetível a contaminação microbiana, comprometendo a qualidade final do produto. Neste sentido, avaliou-se a suscetibilidade a biodeterioração de misturas de diesel com 5, 10 e 20% de biodiesel e de somente de biodiesel, por microrganismos isolados de tanques contaminados, e seu controle com biocidas. Em sistemas contendo meio mínimo mineral e misturas diesel/biodiesel, verificou-se que após 60 dias de crescimento, Paecilomyces sp. formou maior biomassa na formulação B20, Aspergillus fumigatus em B100, e, durante o tempo de crescimento de Candida silvicola e Rhodotorula sp., a maior biomassa foi formada em B100. Candida silvicola apresentou maior capacidade de degradação do biodiesel puro (B100) por cromatografia gasosa acoplada a espectroscopia de massas. As concentrações de 10 e 100ppm apresentaram ação biocida, para os antimicrobianos isotiazolona e oxazolidina, respectivamente. A ação esporicida para ambos biocidas foi de 100ppm. / During the storage, the benefits of biodiesel such as biodegradability, the affinity with the water and the absence of aromatic hydrocarbons makes the fuel even more susceptible to microbial contamination, what affects the quality of the final product. In this sense, the susceptibility to biodeterioration of mixed diesel with 5, 10 and 20% biodiesel and pure biodiesel, by isolated microorganisms from contaminated tanks, and its control with biocides were evaluated. In systems containing minimal medium and mineral mixtures diesel / biodiesel, after 60 days of growth, Paecilomyces sp. formed more biomass in the formulation B20, Aspergillus fumigatus in B100. During the growth period of Candida silvicola and Rhodotorula sp., the largest biomass was formed in B100. Candida silvicola demonstrated great capacity of B100 degradation in evaluation by gas chromatography coupled to mass spectrometry. From the evaluation of minimum inhibitory concentration and biocide, it was determined that in mineral medium and diesel / biodiesel and biocide isotiazolona and the oxazolidina, concentrations of 10ppm and 100ppm were, respectively, esporicides. The concentration of 100ppm, of the both products, was biocidal for the yeasts evalueted.
295

An?lise de desempenho de motor diesel com inje??o eletr?nica Common Rail alimentado com misturas diesel - biodiesel em dinam?metro de chassis / Diesel engine performance analysis with electronic injection Common Rail powered with diesel - biodiesel blends in chassis dynamometer

Podorodeczki, Paulo Ricardo 31 October 2016 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-12-21T10:15:43Z No. of bitstreams: 1 DIS_PAULO_RICARDO_PODORODECZKI_COMPLETO.pdf: 2248928 bytes, checksum: 5045d51346076939fcea5a0a04a7a1a1 (MD5) / Made available in DSpace on 2016-12-21T10:15:44Z (GMT). No. of bitstreams: 1 DIS_PAULO_RICARDO_PODORODECZKI_COMPLETO.pdf: 2248928 bytes, checksum: 5045d51346076939fcea5a0a04a7a1a1 (MD5) Previous issue date: 2016-10-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The present work analyzes the performance and consumption of an electronically managed diesel cycle engine using the Common Rail system equipping a utility vehicle, varying the volume of Biodiesel added to the diesel. The S10 diesel fuel purchased at gas stations, consisting of 7% of Biodiesel already in its composition, and adding Biodiesel in volume of 5 in 5% up to pure Biodiesel (100%) was used for the tests. The tests were carried out on a roller dynamometer in order to obtain and analyze data of torque, power and specific consumption, in order to obtain data for further analysis and make comparisons with previously published theoretical reference. The results showed that there is a better performance range between 10% and 30% where there is a 3% increase in performance with the lowest specific consumption and with the gradual increase of the percentage of Biodiesel, the performance declines of the order of 11, 8% in the maximum torque and 8.2% in the power generated by the engine to 100% Biodiesel, being this one that presented the worst performance. / O presente trabalho analisa a performance e o consumo de um motor de ciclo Diesel gerenciado eletronicamente utilizando o sistema Common Rail equipando um ve?culo utilit?rio, variando-se o volume de Biodiesel adicionado ao Diesel. Utilizou-se para os ensaios o combust?vel Diesel S10 adquirido em postos de combust?veis, constitu?do de 7% de Biodiesel j? em sua composi??o, e adicionando Biodiesel em volume de 5 em 5% at? Biodiesel puro (100%). Os ensaios foram realizados em bancada dinamom?trica de rolos, a fim de obter e analisar dados de torque, pot?ncia e consumo espec?fico, a fim de obter dados para posterior an?lise e realizar compara??es com referencial te?rico publicado anteriormente. Os resultados demonstraram que h? uma faixa de melhor performance entre 10% e 30% onde h? um aumento de performance da ordem de 3% com o menor consumo espec?fico e com o aumento gradativo do percentual de Biodiesel, a performance declina da ordem de 11,8% no torque m?ximo e 8,2% na pot?ncia gerada pelo motor at? Biodiesel 100%, sendo esta a que apresentou a pior performance.
296

Resinas de caixa-fria modificadas estruturalmente com propriedades técnicas e meio ambientais melhoradas : sistema BioDiesel

Vilhena, Pedro Miguel Cirurgião Leite de January 2009 (has links)
Estágio realizado em colaboração na FUNDIPOR, produtos para Fundição, Ld.ª, SAKTHI Portugal, S.A. e HÜTTENES-ALBERTUS GmbH / Tese de mestrado integrado. Engenharia Metalúrgica e de Materiais. Faculdade de Engenharia. Universidade do Porto. 2009
297

Transesterification of vegetable oils in supercritical fluids for biodiesel production

Nogueira, José Miguel Lopes Maçaira January 2010 (has links)
Estágio realizado na ETSEIB: Escola Técnica Superior d'Enginyeria Industrial de Barcelona e orientado pela Drª. Maria Angels Larrayoz / Tese de mestrado integrado. Engenharia Química. Faculdade de Engenharia. Universidade do Porto. 2010
298

Inventário e caracterização de resíduos animais com potencialidades para a produção de biodiesel na região do Grande Porto

Cardoso, Lucinda Fernanda Moreira January 2009 (has links)
Tese de mestrado integrado. Engenharia Química. Faculdade de Engenharia. Universidade do Porto. 2009
299

Cultivo de higuerilla (Ricinus communis L.) como materia prima para la elaboración de biodiésel / Cultivation of higuerilla (Ricinus communis L.) as raw material for the elaboration of biodiesel

Delgado Valenzuela, Francisco Guillermo January 2013 (has links)
Memoria para optar al título profesional de: Ingeniero Agrónomo / La creciente preocupación por la continua alza en los precios de los combustibles fósiles y la contaminación ambiental producto de los gases de efecto invernadero, ha motivado la búsqueda de nuevas alternativas de fuentes de combustión, que ofrezcan mayor independencia energética y sean más inocuas con el medio ambiente. Una alternativa es el cultivo de especies con potencial bioenergético, como es el caso de la higuerilla (Ricinus communis L.), de la cual es posible elaborar biodiésel a partir del aceite de sus semillas. El presente estudio se enfocó en recopilar información sobre esta especie, relacionada principalmente a sus requerimientos agronómicos, su uso como materia prima en fabricación de biodiésel, así como profundizar en los antecedentes necesarios para su cultivo en Chile, que permitan decidir por ejemplo: el lugar, fechas y modo de establecimiento. También se hace mención de las principales plagas y enfermedades que pudiesen afectar su cultivo, junto con los demás usos que pueden darse al aceite de esta especie, principalmente vinculados todos ellos al área industrial. Se determinaron también las zonas más apropiadas en Chile para el establecimiento de un cultivo de higuerilla, en función de los requerimientos edafoclimáticos de esta especie y las características climatológicas de los distritos bioclimáticos presentes en el país. Además, se realizó una estimación de costos y prefactibilidad para una producción de semillas de higuerilla en una superficie de 1 ha. Para la realización de esta investigación, se recurrió principalmente a estudios realizados en Universidades y Departamentos Agrícolas de países Latinoamericanos como Brasil, Colombia y Ecuador, que llevan varios años cultivando higuerilla, así como publicaciones FAO y CEPAL, pues al no ser la higuerilla una especie cultivada en Chile, la información es relativamente escasa a nivel nacional. / The growing concern about the continued rise in the price of fossil fuels and environmental pollution arising from greenhouse gases has motivated the search for new alternative fuel sources that offer greater energy independence and be more environmentally friendly atmosphere. An alternative is the cultivation of bioenergy potential species, as in the case of higuerilla (Ricinus communis L.), which is possible to produce biodiesel from oil seeds. This study focused on collecting information on this species, mainly due to its agronomic requirements, use as feedstock in biodiesel production, as well as deepen the necessary background for cultivation in Chile, in order to decide for example, the place dates and setting mode. References to major pests and diseases that may affect its culture, along with other uses that may be the oil of this species, all of them linked primarily to the industrial area is also made. Chile the most appropriate for the establishment of a cultivation of higuerilla, depending on the soil and climate requirements of this species and the climatic characteristics of the districts bioclimatic zones in the country were also determined. In addition, a cost estimate and feasibility for higuerilla seed production in an area of 1 ha was performed. To carry out this research, mainly turned to studies in Universities and Agricultural Departments of Latin American countries like Brazil, Colombia and Ecuador, who have spent several years cultivating higuerilla and publications FAO and CEPAL, as to not be the higuerilla kind cultivated in Chile, the information is relatively scarce nationwide.
300

Energy and Water Conservation in Biodiesel Purification Processes

Hastie, Michele 14 November 2011 (has links)
Biodiesel purification processes generate wastewater streams that require a large amount of energy when distillation is used as a treatment technology. Process simulation software was used to show that an alternative water treatment process involving ion exchange would require only 31% of the energy used by distillation. Experiments showed that multiple washing stages were required to meet the standard specification for sodium, an impurity present in crude biodiesel, when washing biodiesel made from used frying oil. A comparison was made between washing biodiesel in a cross-current washing configuration and a counter-current configuration. Both configurations met the specification for sodium within three washing stages; however, the counter-current configuration required less water, making it the more efficient process. Lastly, the removal of sodium from wastewater samples using an ion exchange resin was experimentally investigated. The results validated the use of ion exchange to reduce energy consumption in biodiesel purification.

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