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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.
21

O circuito espacial da produ??o petrol?fera no Rio Grande do Norte

Alves, Sandra Priscila 22 March 2012 (has links)
Made available in DSpace on 2015-03-13T17:10:48Z (GMT). No. of bitstreams: 1 SandraPA_DISSERT_.pdf: 6038687 bytes, checksum: 3a64b39d14e021c1abe47d90598f9430 (MD5) Previous issue date: 2012-03-22 / Our study refers to the state of Rio Grande do Norte against the deployment of oil activity in their territory. In this sense the aim of this work was to analyze the presence of the loop space of the oil production system linked to objects and actions on the Rio Grande do Norte territory. From the so-called "oil shock", an event that caused global developments in several countries, Petr?leo Brasileiro S/A (PETROBRAS) increased investments in drilling geological basins in Brazil. In the year 1973 was drilled in the sea area well which led to commercial production of oil and gas in Rio Grande do Norte. From that point on were added in some parts of the Potiguar territory, large systems of coupled objects to actions caused by several agents. In this context, geographic situations have been reorganized due to an unprecedented space circuit production accompanied by a new circle of cooperation. In the state happen all instances of the circuit: the production, distribution and consumption. In light of the theory of the geographical area seek to direct our thoughts to the operation of these bodies, and they are linked to material and immaterial flows multiscales. This perspective allows us to think the territory of Rio Grande do Norte entered into a new territorial division of labor characterized by specialization regional production. Oil activity was implemented in the territory of Rio Grande do Norte at a time marked by productive restructuring of various economic sectors. The oil sector has been acting increasingly linked the scientific and informational, with a view to increasing productivity. The presence of this circuit demanded the territory, specifically the Mossor?, an organizational structure that is different from the vast system nationally integrated private commercial corporations to small corporations, all of them relating directly or indirectly to PETROBRAS. The flows between companies whose headquarters are located in distant states and even countries have generated a continuous movement of goods, people, information and ideas, which is also causing new materialities in the territory / Nosso estudo se remete ao estado do Rio Grande do Norte frente ? implanta??o da atividade petrol?fera em seu territ?rio. Nesse sentido o objetivo geral do trabalho consistiu em analisar a presen?a do circuito espacial da produ??o petrol?fera vinculado ao sistema de objetos e de a??es presentes no territ?rio norte-rio-grandense. A partir do chamado choque do petr?leo , acontecimento mundial que causou desdobramentos em v?rios pa?ses, a Petr?leo Brasileiro S/A (PETROBRAS) aumentou os investimentos em perfura??es nas bacias geol?gicas brasileiras. No ano de 1973 foi perfurado em ?rea mar?tima o po?o que deu origem ? produ??o comercial de petr?leo e g?s no Rio Grande do Norte. Desse momento em diante foram acrescentados em algumas parcelas do territ?rio potiguar, grandes sistemas de objetos, juntamente, ?s a??es provocadas por agentes diversos. Nesse contexto, situa??es geogr?ficas foram reorganizadas em fun??o de um in?dito circuito espacial de produ??o acompanhado de um novo c?rculo de coopera??o. No estado acontecem todas as inst?ncias do circuito: a produ??o, a distribui??o e o consumo. ? luz da teoria do espa?o geogr?fico procuramos direcionar as nossas reflex?es ao funcionamento destas inst?ncias, estando elas ligadas a fluxos materiais e imateriais multiescalares. Essa perspectiva nos autoriza a pensar o territ?rio norte-rio-grandense inserido em uma nova divis?o territorial do trabalho marcada pela especializa??o regional produtiva. A atividade petrol?fera implantou-se no territ?rio norte-rio-grandense em um momento marcado pela reestrutura??o produtiva de diversos segmentos econ?micos. O setor petrol?fero passou a atuar cada vez mais atrelado ?s bases cient?ficas e informacionais, tendo em vista o aumento da produtividade. A presen?a desse circuito demandou ao territ?rio, mais especificamente a Mossor?, uma diversa estrutura organizacional que ocorre desde o vasto sistema nacionalmente integrado de corpora??es comerciais privadas at? as pequenas empresas, todas elas relacionando-se diretamente ou indiretamente com a PETROBRAS. Os fluxos entre empresas, cujas sedes localizam-se em estados e mesmo pa?ses distantes, t?m gerado um movimento cont?nuo de produtos, pessoas, informa??es e ideias, o que vem provocando tamb?m novas materialidades no territ?rio
22

O trabalho em produção contínua: uma abordagem ergonômica na indústria do petróleo. / The work in continuous production: an ergonomic approach at the oil industry.

Luciano do Valle Garotti 06 November 2006 (has links)
Esta dissertação apresenta um estudo ergonômico sobre o trabalho de operadores de processo de plataformas marítimas de produção de petróleo. As primeiras investigações sobre as atuais práticas e produtos finais de projetos de sistemas produtivos de grande porte resultaram em indícios de um ambiente de produção com aspectos operacionais não equilibrados e desintegrados. A partir destes indícios, foi realizada uma revisão bibliográfica que destacou as considerações e limitações de aspectos relacionados à Ergonomia em assuntos como gestão de projetos, projetos de engenharia, de sistemas produtivos e de arranjo físico. A revisão relativa à Ergonomia destacou seus conceitos básicos, a Ergonomia de Concepção e estudos relacionados ao trabalho de operadores de produção contínua, tendo o objetivo de indicar possibilidades de atuações desta ciência em projetos de plantas produtivas. Desta forma, a pesquisa de campo desenvolvida procurou destacar aspectos operacionais como dificuldades e constrangimentos enfrentados pelos operadores. Tais aspectos foram investigados com o objetivo de ressaltar os desequilíbrios presentes nesta situação de trabalho e as estratégias desenvolvidas por estes operadores para manterem o funcionamento satisfatório da unidade produtiva, atendendo aos objetivos da organização empresarial em que se inserem. / This work presents the ergonomics study based on offshore oil production platforms, in operation works for the process plant. The first investigations resulted on indications of disintegrated and unbalanced operational aspects into the production environment. From those evidences, the bibliographical revision indicated the considerations and limits of aspects related to Ergonomics in subjects as design management, engineering design, productive systems and layout design. The revision of Ergonomics included basic concepts, Ergonomics of Conception, and studies related to the operator works of continuous production process, having the aim of indicating participation possibilities of this science in production plants design. In such a way, the developed research tried to raise operational aspects as difficulties and constraints daily faced by operators. Such aspects were investigated intending to stand out the disequilibriums in this situation of work and strategies developed by these operators to keep satisfactory performance of a productive unit, taking care of company goals where they are inserted.
23

Identificação de parâmetros de motor de indução linear tubular para extração de petróleo. / Identification of parameters of the tubular linear induction motor for the extraction of oil.

Wagner Marques Rossini 22 February 2008 (has links)
O presente trabalho apresenta a identificação de parâmetros de motor de indução linear tubular para a extração de petróleo, denominado de MATÆOS -- Motor Assíncrono Tubular para Aplicação na Extração de Óleo Subterrâneo. O primeiro passo para a identificação de parâmetros do motor foi a implementação da bancada de testes com o seu sistema de controle e supervisório. O modelo adotado corresponde à situação de operação em regime estacionário e consiste no circuito contendo resistores e indutores tradicionalmente utilizado para representar motores de indução. A identificação dos parâmetros foi realizada por meio de um procedimento de otimização tomando por base o balanço de potência do motor. Para isso, em função dos parâmetros do modelo, definiu-se e minimizou-se uma medida de erro entre as potências medidas e as calculadas pelo modelo para um conjunto pré-fixado de escorregamentos. A solução desse problema de otimização foi obtida por meio de uma busca exaustiva, uma vez que o número de variáveis independentes do problema é pequeno e uma região contendo o ponto de mínimo é conhecida com razoável confiança. Os resultados obtidos indicam que os valores dos parâmetros nominais a quente apresentam algumas diferenças em relação àqueles produzidos pelo método de identificação. Essas diferenças se devem possivelmente a variações nas características térmicas do motor e a erros introduzidos pelos instrumentos de medida. O modelo identificado apresentou uma menor disponibilidade de força e um pior rendimento quando comparado com os valores de projeto do modelo nominal a quente. Apesar disto, verificou-se uma boa proximidade entre a curva característica do modelo e as obtidas experimentalmente. / This work presents the identification of parameters of the tubular linear induction motor for the extraction of oil, called MATÆOS - which is the Portuguese acronym for Asynchronous Tubular Motor for Application to Subterranean Oil Extraction. The first step to the identification of the motor parameters was the implementation of the supervisory and control system for the test bench. The model, which is the usual one containing resistors and inductors, represents the motor operating in steady-state. The parameter identification problem was written as an optimization problem based on the motor power balance. An error between the measured power and the one given by the model was defined and minimized with respect to the model parameters in correspondence to a given set of slipping frequencies. The numerical solution to this problem was obtained by an exhaustive search algorithm. This choice was made because the number of independent variables is small and a region containing the solution is known with a significant degree of confidence. The results obtained show that the nominal values of the model parameters differ slightly from those produced by the identification method. Possibly, such differences are due to the variations in the model caused by temperature changes and to the measurement errors. The identified model presented both a lower available force and a worst efficiency when compared to the nominal design values for the warm motor. Despite this the characteristic curve of the model was quite close to the nominal design one.
24

Controle de sistema de mancais magnéticos ativos para um motor de indução linear tubular. / Control system applied to active magnetic bearings for a tubular linear induction motor.

Leandro Henrique Monaco 08 October 2012 (has links)
Para aplicações de extração de petróleo de poços em terra foi desenvolvido pelo Laboratório de Eletromagnetismo Aplicado (LMAG) da Escola Politécnica da Universidade de São Paulo um protótipo de motor de indução linear tubular (MILT), onde o movimento axial do secundário do motor aciona diretamente a bomba de extração situada no fundo do poço. Numa segunda etapa, foi prevista a substituição dos mancais mecânicos por dois mancais magnéticos ativos (AMBs), que permitem melhor movimentação e praticamente nenhum atrito, reduzindo o desgaste causado por impurezas contidas no petróleo extraído, e consequentemente os esforços de manutenção. Todavia, o protótipo atual possui apenas um mancal magnético, e o outro é mecânico. O presente trabalho apresenta a instalação do segundo mancal magnético ao protótipo do MILT, e propõe realizar o controle do sistema de mancais magnéticos para o MILT, tendo em vista um problema multivariável, onde as posições do secundário do motor em relação aos dois mancais são correlacionadas, bem como as ações de controle sobre os mesmos. O trabalho faz uma revisão do sistema atual com um AMB, abordando sua concepção física, modelagem e o controlador, e tal controlador é replicado para o segundo AMB. Um novo modelo é apresentado, considerando o comportamento multivariável dos dois AMBs, e um sistema de controle robusto multivariável é projetado, através da técnica LQG/LTR. Resultados de simulação do novo controlador são analisados e comparados com os resultados experimentais do controlador atual aplicado aos dois AMBs, e apresentam-se as conclusões. / For onshore oil extraction applications, a tubular linear induction motor (TLIM) prototype was developed by Applied Electromagnetism Laboratory (LMAG) of Escola Politécnica da Universidade de São Paulo, on which the axial movement of the motor secondary drives the suction pump, placed in the down hole of the oil well. In a second step, it was planned to replace the mechanical bearings by two Active Magnetic Bearings (AMB), in order to have better movement and practically no friction, reducing damages caused by impurities in the oil, thus reducing maintenance effort. Nevertheless, the actual prototype has only one AMB, being the other one a mechanical bearing. This paper presents the installation of the second AMB onto TLIM prototype, and a proposal to implement the control algorithm for the TLIM magnetic bearing system, considering now a multivariable problem, where the position of the motor secondary for both AMB are related, as well as control efforts. The present work review the actual system with only one AMB, approaching its physical construction, mathematical model and applied control system; and this control system is applied to the second AMB. A new model is presented, considering the AMB system multivariable behavior, and a multivariable robust control system is then designed, using LQG/LTR approach. Simulation results for the new controller are analyzed and compared to experimental results from the actual controller applied to both AMB, and some conclusions are presented.
25

Estudo analítico, térmico e energético do pinhão manso (Jatropha Curcas l.) como matéria-prima para a produção de biocombustíveis

Souza, Cristiane Daliassi Ramos de 10 November 2012 (has links)
Submitted by Lúcia Brandão (lucia.elaine@live.com) on 2015-07-15T16:05:00Z No. of bitstreams: 1 Tese - Cristiane Daliassi Ramos de Souza.pdf: 2429333 bytes, checksum: 3abea0012ee786e4320f226b2f591475 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-20T15:48:37Z (GMT) No. of bitstreams: 1 Tese - Cristiane Daliassi Ramos de Souza.pdf: 2429333 bytes, checksum: 3abea0012ee786e4320f226b2f591475 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-20T15:54:41Z (GMT) No. of bitstreams: 1 Tese - Cristiane Daliassi Ramos de Souza.pdf: 2429333 bytes, checksum: 3abea0012ee786e4320f226b2f591475 (MD5) / Made available in DSpace on 2015-07-20T15:54:42Z (GMT). No. of bitstreams: 1 Tese - Cristiane Daliassi Ramos de Souza.pdf: 2429333 bytes, checksum: 3abea0012ee786e4320f226b2f591475 (MD5) Previous issue date: 2012-11-10 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Jatropha curcas L. is a vegetable species that supplies great amount of oil, but due to its toxicity cannot be used to feed human beings. It is a promising alternative for Biodiesel production. This Thesis had the purpose of perform analytic, thermal and energy studies for the oil extracted from oleaginous species Jatropha curcas L., cultivated in the State of Amazonas. The study was also done for byproducts such as fruit peels, seed peels and the cake originated by biofuel productive chain. To reach the proposed objective, the experimental activities were started with the sampling of the whole fruits in a plantation located in Itacoatiara city-Amazonas. Six independent samplings were done in different months and all the samples were submitted to physical characterization to evaluate size and weight for all parts of the fruit. The process to obtain the oil was done by two methods: mechanical extraction and chemical extraction (Soxhlet system). The chemical extraction was performed for all available samples and the best efficiency was the 50.21%, although all the extractions have presented good results (43-48%). The mechanical process was just performed for the 2010 crop presenting a satisfactory efficiency (33.14%). Then, the oil extracted by the two processes was characterized by several physical-chemical parameters. The oxidative stability by Rancimat was measured for the oils and the result was around 12 hours, this value is considered satisfactory when compared with other species. The fatty acid profile was analyzed by gas chromatography, which indicated the presence of higher concentrations of oleic and linoleic acids. The palmitic, stearic, arachidic and palmitoleic acids were also detected, however in smaller concentrations. The evaluation for thermal and energy potential was done for the oil and byproducts using TG/DTA, immediate analysis and superior heat power techniques. The results of thermal analysis for the oils obtained by chemical and mechanical extraction indicated thermal stability temperature about 180 and 217°C, respectively. Energy evaluation for byproducts was done by immediate analysis and high values for volatile materials were found (65-78%). These values characterize a fuel that can be easy and quickly burned during the combustion process. The results of PCS for the obtained oils presented high values (34-39 MJ/kg), which are close to the ones measured for diesel. For the byproducts, the results were between 17 and 21 MJ/kg, close and even superiors to the literature values for other agricultural residues showing, therefore, great applicability for use in energy generation processes. Finally, reactions with the Jatropha curcas L. oil were made to obtain biofuels through the methylic and ethylic transesterification and thermal cracking. The results for transesterification process were excellent, with efficiency above 90%, however, the physical-chemical evaluation showed that the methylic Biodiesel was the only one in conformity with the Resolution 14/2011 from ANP. A satisfactory efficiency of 75% was obtained for bio-oil. / O pinhão manso é uma espécie vegetal que fornece grande quantidade de óleo e por sua toxidade não pode ser usado na alimentação humana, podendo se transformar em uma alternativa promissora na produção de Biodiesel. Esta Tese teve a finalidade de realizar um estudo analítico, térmico e energético do óleo extraído da espécie oleaginosa pinhão manso (Jatropha curcas L.), cultivada no Estado do Amazonas, assim como dos co-produtos, tais como, cascas do fruto, cascas da semente e torta, presentes na cadeia produtiva de biocombustíveis. Para atingir o objetivo proposto, as atividades experimentais foram iniciadas com a coleta dos frutos na plantação localizada em Itacoatiara-AM. Foram feitas seis coletas em diferentes meses e todas as amostras foram submetidas à caracterização física avaliando o tamanho e a massa para todas as partes do fruto. Em seguida realizou-se o processo de obtenção do óleo, utilizando dois métodos, a extração mecânica e a extração com solvente (Método Soxhlet). A extração com solvente foi realizada para todas as amostras coletadas e o melhor rendimento obtido foi de 50,21%, apesar de ter obtido bons resultados em todas as extrações (43-48%). O processo mecânico foi realizado apenas com o lote da safra de 2010 apresentando um rendimento satisfatório (33,14%). Posteriormente, o óleo extraído foi caracterizado por diversos parâmetros físico-químicos. A estabilidade oxidativa por Rancimat foi realizada para o óleo do pinhão manso ficando em torno de 12 horas, um valor considerado satisfatório quando comparado com outras espécies. O perfil de ácidos graxos foi analisado por cromatografia gasosa, o qual indicou a presença de altas concentrações dos ácidos oléico e linoléico. Os ácidos palmítico, esteárico, araquídico e palmitoléico também foram detectados, porém em concentrações menores. A avaliação do potencial térmico e energético foi realizada para o óleo e os co-produtos utilizando as técnicas de TG/DTA, análise imediata e PCS. Os resultados da análise térmica dos óleos, obtidos via extração química e mecânica, indicaram uma temperatura de estabilidade térmica em torno de 180C e 217C, respectivamente. Na avaliação energética dos co-produtos realizada pela análise imediata houve destaque para o teor de materiais voláteis, que apresentou valores elevados (65-78%), o que caracteriza um combustível mais fácil e rapidamente queimado durante o processo de combustão. Os resultados do PCS para os óleos obtidos apresentaram valores elevados (34-39 MJ/kg) e próximos ao diesel. Para os co-produtos, os resultados ficaram entre 17 e 21 MJ/kg, próximos e até superiores aos valores reportados na literatura para outros resíduos agrícolas mostrando, portanto grande aplicabilidade para utilização em processos de geração de energia. Por fim foram realizadas reações com o óleo de pinhão manso para obter biocombustíveis através da transesterificação metílica e etílica e do craqueamento térmico. Os resultados da transesterificação mostraram-se excelentes, com rendimentos acima de 90%, entretanto a avaliação físico-química mostrou que apenas o Biodiesel metílico ficou em conformidade com a Resolução 14/2011 da ANP. O Bio-óleo obteve um rendimento satisfatório (75%).
26

Isolation and identification of native microalgae for biodiesel production

Abdelaziz, Ahmed E. M. 01 1900 (has links)
La demande croissante en carburants, ainsi que les changements climatiques dus au réchauffement planétaire poussent le monde entier à chercher des sources d’énergie capables de produire des combustibles alternatifs aux combustibles fossiles. Durant les dernières années, plusieurs sources potentielles ont été identifiées, les premières à être considérées sont les plantes oléagineuses comme source de biocarburant, cependant l’utilisation de végétaux ou d’huiles végétales ayant un lien avec l’alimentation humaine peut engendrer une hausse des prix des denrées alimentaires, sans oublier les questions éthiques qui s’imposent. De plus, l'usage des huiles non comestibles comme sources de biocarburants, comme l’huile de jatropha, de graines de tabac ou de jojoba, révèle un problème de manque de terre arable ce qui oblige à réduire les terres cultivables de l'industrie agricole et alimentaire au profit des cultures non comestibles. Dans ce contexte, l'utilisation de microorganismes aquatiques, tels que les microalgues comme substrats pour la production de biocarburant semble être une meilleure solution. Les microalgues sont faciles à cultiver et peuvent croitre avec peu ou pas d'entretien. Elles peuvent ainsi se développer dans des eaux douces, saumâtres ou salées de même que dans les terres non cultivables. Le rendement en lipide peut être largement supérieur aux autres sources de biocarburant potentiel, sans oublier qu’elles ne sont pas comestibles et sans aucun impact sur l'industrie alimentaire. De plus, la culture intensive de microalgues pour la production de biodiesel pourrait également jouer un rôle important dans l'atténuation des émissions de CO2. Dans le cache de ce travail, nous avons isolé et identifié morphologiquement des espèces de microalgues natives du Québec, pour ensuite examiner et mesurer leur potentiel de production de lipides (biodiesel). L’échantillonnage fut réalisé dans trois régions différentes du Québec: la région de Montréal, la gaspésie et le nord du Québec, et dans des eaux douces, saumâtres ou salées. Cent souches ont été isolées à partir de la région de Montréal, caractérisées et sélectionnées selon la teneur en lipides et leur élimination des nutriments dans les eaux usées à des températures différentes (10 ± 2°C et 22 ± 2°C). Les espèces ayant une production potentiellement élevée en lipides ont été sélectionnées. L’utilisation des eaux usées, comme milieu de culture, diminue le coût de production du biocarburant et sert en même temps d'outil pour le traitement des eaux usées. Nous avons comparé la biomasse et le rendement en lipides des souches cultivées dans une eau usée par apport à ceux dans un milieu synthétique, pour finalement identifié un certain nombre d'isolats ayant montré une bonne croissance à 10°C, voir une teneur élevée en lipides (allant de 20% à 45% du poids sec) ou une grande capacité d'élimination de nutriment (>97% d'élimination). De plus, nous avons caractérisé l'une des souches intéressantes ayant montré une production en lipides et une biomasse élevée, soit la microalgue Chlorella sp. PCH90. Isolée au Québec, sa phylogénie moléculaire a été établie et les études sur la production de lipides en fonction de la concentration initiale de nitrate, phosphate et chlorure de sodium ont été réalisées en utilisant de la méthodologie des surfaces de réponse. Dans les conditions appropriées, cette microalgue pourrait produire jusqu'à 36% de lipides et croitre à la fois dans un milieu synthétique et un milieu issu d'un flux secondaire de traitement des eaux usées, et cela à 22°C ou 10°C. Ainsi, on peut conclure que cette souche est prometteuse pour poursuivre le développement en tant que productrice potentielle de biocarburants dans des conditions climatiques locales. / The continuing increase in fuel demands, the dramatic situation in climate changes and the global warming are bringing the worldwide attention to the identification of alternative energy source for the production of combustibles that can replace fossil fuel. In last years, a lot of potential sources have been identified: the first potential biofuel feedstock that have been evaluated were oleaginous plants, but the utilization of vegetable, or vegetable oils, that may also be used for human feeding, could lead to the increase of food-grade oils costs and also generate ethic questions. Nevertheless, also using as biofuel sources not-edible oils, like oils from jatropha, tobacco seed or jojoba, the common problem for both edible and not-edible crops is the need to subtract arable land from agriculture and food industry. In this context, the utilization of aquatic microorganisms like microalgae as substrate for the production of biofuel seems to be the better solution. Microalgae are easy to cultivate and can grow with little or no attention, they can grow in fresh, brackish or salt water and in non-arable lands, moreover they are not edible with no consequences on food industry, and the oil productivity, with respect to the other potential biofuel sources, can be much higher. In addition, the intensive cultivation of microalgae for biodiesel production could also play an important role in CO2 mitigation. In this study, we isolated and morphologically identified Québec native micro algal species, surveyed and screened their potential for lipid (biodiesel) production. The sampling efforts made in three different regions of Québec: Montreal area, Gaspesie and Northern of Quebec; on fresh, brackish or saline water. One hundred strains were isolated from the Montreal area, characterized and screened for their lipid content and wastewater nutrient removal under different temperatures (10±2 ºC and 22±2 ºC). The high potential lipid producing algal species were selected. The use of wastewater as a substrate media decreases the economic cost realted to the biofuel production from microalgae as well as an interesting tool for wastewater treatment. We compared the biomass and lipid productivity of these strains on wastewater to a synthetic medium and identified a number of isolates that showed good growth at 10 ºC, gave a high lipid content (ranging from 20% to 45% of dry weight) or a high capacity for nutrient removal (>97% removal). Furthermore, we characterized one of the interesting strains that revealed high lipid and biomass productivity, the novel microalga Chlorella sp. PCH90. Its molecular phylogeny was established and lipid production studies as a function of the initial concentrations of nitrate, phosphate, and sodium chloride were carried out using Response Surface Methodology. Under the appropriate conditions this microalga could produce up to 36% lipid and grew well in both synthetic medium and secondary effluent from a wastewater treatment plant at both 22°C and 10°C. Thus, this strain is promising for further development as a potential biofuels producer under local climatic conditions.
27

Isolation and identification of native microalgae for biodiesel production

Abdelaziz, Ahmed EM 01 1900 (has links)
La demande croissante en carburants, ainsi que les changements climatiques dus au réchauffement planétaire poussent le monde entier à chercher des sources d’énergie capables de produire des combustibles alternatifs aux combustibles fossiles. Durant les dernières années, plusieurs sources potentielles ont été identifiées, les premières à être considérées sont les plantes oléagineuses comme source de biocarburant, cependant l’utilisation de végétaux ou d’huiles végétales ayant un lien avec l’alimentation humaine peut engendrer une hausse des prix des denrées alimentaires, sans oublier les questions éthiques qui s’imposent. De plus, l'usage des huiles non comestibles comme sources de biocarburants, comme l’huile de jatropha, de graines de tabac ou de jojoba, révèle un problème de manque de terre arable ce qui oblige à réduire les terres cultivables de l'industrie agricole et alimentaire au profit des cultures non comestibles. Dans ce contexte, l'utilisation de microorganismes aquatiques, tels que les microalgues comme substrats pour la production de biocarburant semble être une meilleure solution. Les microalgues sont faciles à cultiver et peuvent croitre avec peu ou pas d'entretien. Elles peuvent ainsi se développer dans des eaux douces, saumâtres ou salées de même que dans les terres non cultivables. Le rendement en lipide peut être largement supérieur aux autres sources de biocarburant potentiel, sans oublier qu’elles ne sont pas comestibles et sans aucun impact sur l'industrie alimentaire. De plus, la culture intensive de microalgues pour la production de biodiesel pourrait également jouer un rôle important dans l'atténuation des émissions de CO2. Dans le cache de ce travail, nous avons isolé et identifié morphologiquement des espèces de microalgues natives du Québec, pour ensuite examiner et mesurer leur potentiel de production de lipides (biodiesel). L’échantillonnage fut réalisé dans trois régions différentes du Québec: la région de Montréal, la gaspésie et le nord du Québec, et dans des eaux douces, saumâtres ou salées. Cent souches ont été isolées à partir de la région de Montréal, caractérisées et sélectionnées selon la teneur en lipides et leur élimination des nutriments dans les eaux usées à des températures différentes (10 ± 2°C et 22 ± 2°C). Les espèces ayant une production potentiellement élevée en lipides ont été sélectionnées. L’utilisation des eaux usées, comme milieu de culture, diminue le coût de production du biocarburant et sert en même temps d'outil pour le traitement des eaux usées. Nous avons comparé la biomasse et le rendement en lipides des souches cultivées dans une eau usée par apport à ceux dans un milieu synthétique, pour finalement identifié un certain nombre d'isolats ayant montré une bonne croissance à 10°C, voir une teneur élevée en lipides (allant de 20% à 45% du poids sec) ou une grande capacité d'élimination de nutriment (>97% d'élimination). De plus, nous avons caractérisé l'une des souches intéressantes ayant montré une production en lipides et une biomasse élevée, soit la microalgue Chlorella sp. PCH90. Isolée au Québec, sa phylogénie moléculaire a été établie et les études sur la production de lipides en fonction de la concentration initiale de nitrate, phosphate et chlorure de sodium ont été réalisées en utilisant de la méthodologie des surfaces de réponse. Dans les conditions appropriées, cette microalgue pourrait produire jusqu'à 36% de lipides et croitre à la fois dans un milieu synthétique et un milieu issu d'un flux secondaire de traitement des eaux usées, et cela à 22°C ou 10°C. Ainsi, on peut conclure que cette souche est prometteuse pour poursuivre le développement en tant que productrice potentielle de biocarburants dans des conditions climatiques locales. / The continuing increase in fuel demands, the dramatic situation in climate changes and the global warming are bringing the worldwide attention to the identification of alternative energy source for the production of combustibles that can replace fossil fuel. In last years, a lot of potential sources have been identified: the first potential biofuel feedstock that have been evaluated were oleaginous plants, but the utilization of vegetable, or vegetable oils, that may also be used for human feeding, could lead to the increase of food-grade oils costs and also generate ethic questions. Nevertheless, also using as biofuel sources not-edible oils, like oils from jatropha, tobacco seed or jojoba, the common problem for both edible and not-edible crops is the need to subtract arable land from agriculture and food industry. In this context, the utilization of aquatic microorganisms like microalgae as substrate for the production of biofuel seems to be the better solution. Microalgae are easy to cultivate and can grow with little or no attention, they can grow in fresh, brackish or salt water and in non-arable lands, moreover they are not edible with no consequences on food industry, and the oil productivity, with respect to the other potential biofuel sources, can be much higher. In addition, the intensive cultivation of microalgae for biodiesel production could also play an important role in CO2 mitigation. In this study, we isolated and morphologically identified Québec native micro algal species, surveyed and screened their potential for lipid (biodiesel) production. The sampling efforts made in three different regions of Québec: Montreal area, Gaspesie and Northern of Quebec; on fresh, brackish or saline water. One hundred strains were isolated from the Montreal area, characterized and screened for their lipid content and wastewater nutrient removal under different temperatures (10±2 ºC and 22±2 ºC). The high potential lipid producing algal species were selected. The use of wastewater as a substrate media decreases the economic cost realted to the biofuel production from microalgae as well as an interesting tool for wastewater treatment. We compared the biomass and lipid productivity of these strains on wastewater to a synthetic medium and identified a number of isolates that showed good growth at 10 ºC, gave a high lipid content (ranging from 20% to 45% of dry weight) or a high capacity for nutrient removal (>97% removal). Furthermore, we characterized one of the interesting strains that revealed high lipid and biomass productivity, the novel microalga Chlorella sp. PCH90. Its molecular phylogeny was established and lipid production studies as a function of the initial concentrations of nitrate, phosphate, and sodium chloride were carried out using Response Surface Methodology. Under the appropriate conditions this microalga could produce up to 36% lipid and grew well in both synthetic medium and secondary effluent from a wastewater treatment plant at both 22°C and 10°C. Thus, this strain is promising for further development as a potential biofuels producer under local climatic conditions.
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Characterization of microalgae native to Quebec for biofuel production

Leite, Gustavo Balduino 12 1900 (has links)
No description available.
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Optimalizace extrakce bioaktivních látek z bylin do různých druhů méně známých olejových základů / Optimalization of the extraction of bioactive compounds from herbs into different kind of oil bases

Chytil, Dalibor January 2020 (has links)
This diploma thesis deals with the optimization of processes for extraction of bioactive lipophilic compounds from fruits of sea buckthorn (Hippophae Rhamnoides) into various types of plant oil bases using simple maceration. The theoretical part of this thesis deals with the characterization of this herb, its botanical classification, traditional use, chemical composition and medicinal effects. Increased attention is also paid to the characterization of individual types of plant oils used, namely camellia, camellia organic, passionflower, kukui and kiwi oil. The experimental part of the thesis deals with application of theoretical knowledge. The profile of total and free fatty acids for individual plant oil bases was determined by GC/FID, furthet the basic fat numbers were also determined. When optimizing the extraction, emphasis was placed not only on the effect of the extraction agent used, but also on the extraction time (1, 3, 5, 7, 10, 14, 21 and 66 days). The macerates were continuously subjected to the determination of selected parameters (total amount of carotenoids, total amount of phytosterols, lutein, neoxanthin, astaxanthin, stigmasterol, -sitosterol and vitamin E) using UV-VIS spectroscopy and HPLC/PDA. Likewise, the peroxide number was monitored during maceration to assess the degree of oxidative degradation of macerates. The recovery of selected total parameters in individual oils did not differ significantly in most cases. On the contrary, the yield of individual monitored parameters differed significantly. At the same time, static maceration under our conditions was not very suitable for the extraction of vitamin E, stigmasterol and total phytosterols.

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