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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

Approche aux différentes échelles pour la mise au point d’outils intégrés d’aide au développement de projets de méthanisation / Approach at various scales for the biogas plant development

Tolo, Julien 08 April 2014 (has links)
La digestion anaérobie est un processus biologique de transformation de la matière organique permettant la production d’énergie sous forme de biogaz et de fertilisant sous forme de digestat. C’est une filière émergente en France, dont les objectifs de développement sont ambitieux. Le développement d’une filière industrielle sur l’ensemble du territoire Français nécessite la mise en oeuvre d’outils d’aide à la décision.Dans le cadre de cette Thèse nous proposons d’évaluer le potentiel de développement de la méthanisation collective, territoriale et agricole par injection du biogaz dans les réseaux de gaz naturel. Les travaux de recherchent portent sur trois axes : (1)l’évaluation du potentiel de mobilisation de biomasse d’origine agricole ; (2) la conception et l’étude de la viabilité économique de « modèle type » d’usine de méthanisation ; (3) l’évaluation de la performance technico-économique d’une exploitation agricole ayant recours à la méthanisation dans but d’accroitre son autonomie face aux énergies fossiles et aux engrais chimiques.Sur le premier volet, nous avons réalisé une étude cartographique des gisements agricoles mobilisables. Nous avons localisé et quantifié les quantités de coproduits de cultures et d’effluents d’élevage présent sur le territoire Français. Nous avons mis en évidence que le potentiel de mobilisation de biomasse agricole est de l’ordre de 57millions de tonnes de matière sèche. Ceci correspond à une production énergétique maximale de l’ordre de 158 TWh/an.Sur le deuxième volet, nous avons conçu des « modèles types » d’usines de méthanisation de différentes tailles, dont le biogaz est valorisé en biométhane par injection dans le réseau. Pour chacun des « modèles types » nous avons comparé la viabilité technico-économiques des modèles selon différentes « recettes » de biomasse. L’évaluation met en avant que pour chaque « modèle type », il existe un nombre limité de « recettes » permettant à chacun d’entre eux de trouver un équilibre technico-économique.Sur le troisième volet, nous nous sommes intéressés à l’autonomie azote et carburant que pourrait atteindre une exploitation agricole en méthanisant des cultures énergétiques dédiées de légumineuse. L’évaluation a été menée sur des fermes présentant des configurations différentes d’assolement et de rendement. Nous avons mis en évidence les conditions nécessaires pour que chaque configuration de ferme puisse atteindre l’autonomie. Il en ressort que dans certaines conditions, une exploitation « autonome » présente des marges brutes supérieures à celle d’une exploitation conventionnelle. / Anaerobic digestion is a biological process of transformation of organicmatter allowing the production of energy in the form of biogas and fertilizer in the formof digestate. It is an emerging sector in France, whose development objectives are ambitious. The development of an industrial sector throughout the French territory requires the implementation of decision support tools.As part of this thesis, we propose to evaluate the development potential of collective,territorial and agricultural methanation by injecting biogas into natural gas networks.Research work focuses on three axes: (1) the evaluation of the biomass mobilization potential of agricultural origin; (2) the design and study of the economic viability of a"typical model" of methanation plant; (3) the evaluation of the technical and economic performance of a farm using methanation in order to increase its autonomy in the face of fossil fuels and chemical fertilizers.We first carried out a cartographic study of mobilizable agricultural deposits. The quantities of co-products of crops and livestock effluents present on the French territor ywere located and quantified. Thus, we have shown that the potential for mobilization of agricultural biomass is of the order of 57 million tons of dry matter. This corresponds to a maximum energy production of about 158 TWh / year.And second, we have designed "model models" of biogas plants of different sizes,whose biogas is valorized in biomethane by injection into the network. For each of the"standard models" we compared the techno-economic viability of the models according to different "recipes" of biomass. The evaluation points out that for each "standard model" there is a limited number of "recipes" allowing each of them to find a technoeconomic balance.Finally, we focused on the nitrogen and fuel autonomy that an agricultural operationcould achieve by methanising dedicated energy crops of legumes. The assessment was conducted on farms with different rotational and yield configurations. We have highlighted the conditions necessary for each farm configuration to achieve autonomy.It shows that under certain conditions, an "autonomous" farm has gross margins higher than that of a conventional farm.
12

Modificação física de farinha de araruta para aplicação em massa alimentícia enriquecida com coprodutos agroindustriais / Physical modification of arrowroot flour for application in pasta enriched with agroindustrial coproducts

Fideles, Marília Cândido 20 December 2019 (has links)
Submitted by Liliane Ferreira (ljuvencia30@gmail.com) on 2019-01-29T14:52:14Z No. of bitstreams: 2 Dissertação - Marília Cândido Fideles - 2018.pdf: 3128955 bytes, checksum: 7c96987d4cfb19f05d0952999fb570df (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2019-01-30T09:52:29Z (GMT) No. of bitstreams: 2 Dissertação - Marília Cândido Fideles - 2018.pdf: 3128955 bytes, checksum: 7c96987d4cfb19f05d0952999fb570df (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2019-01-30T09:52:29Z (GMT). No. of bitstreams: 2 Dissertação - Marília Cândido Fideles - 2018.pdf: 3128955 bytes, checksum: 7c96987d4cfb19f05d0952999fb570df (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2019-12-20 / Arrowroot is a plant that has abundant starch content and does not present gluten in its composition, arousing the interest of its use in the production of pasta. However, gluten substitution must be provided through the use of techniques, such as the arrowroot flour modification through physical processes. Starch is the highest percentage of arrowroot composition, so enrichment of the dough is an interesting alternative, and a fortification with agroindustrial coproducts sources of fiber and protein, such as passion fruit peel and bovine rumen, may be viable. The objective of this study is to produce flours from agroindustrial coproducts, to modify by different methods (ultrassonic and heat-moisture treatment) the starch of arrowroot obtained and determine the viability technological and nutritional aspects of the use of modified flours and agroindustrial coproducts, source of fiber and protein, in the production of different types of pasta. The hydration, paste and thermal properties of raw and modified flours were evaluated. The results of the ultrasound treatments vary with the temperature between 35.83 and 62% with time between 5 and 15 minutes. For heat-moisture treatment, the best results were those using the lowest temperature (105 ° C) and shorter times (15 and 30 minutes). Taking into account the use of modified flours in the production of pasta, ultrasonic treatments with parameters of intensity of 43.5% and time of 15 min and heat-moisture treatment with 105 ° C for 15 min were selected. With the technological techniques of the pasta produced, it was possible to analyze and choose the best parameters to obtain a pasta with less cooking time, loss of solids, intermediate increase of pasta, and small values of firmness, angle Hue and C* chromaticity. The proximal composition of the pasta was satisfactory, being able to be characterized as a food with high protein content and high fiber content. The pastas with the greatest desirability are a good sensory acceptance. The results obtained have the possibility to develop and improve the pasta formulated with raw and modified arrowroot flour and agroindustrial coproducts. / A araruta é uma planta que apresenta conteúdo abundante de amido e não glúten em sua composição, despertando o interesse da sua utilização na produção de massas alimentícias. Porém a substituição do glúten deve ser suprida através da utilização de diferentes técnicas, como, por exemplo, a modificação da farinha por meio de processos físicos. O amido é o maior percentual da composição da araruta, portanto o enriquecimento da massa é uma alternativa interessante, e a fortificação com coprodutos agroindustriais fontes de fibra e proteína, como a casca de maracujá e o rúmen bovino, pode ser viável. O objetivo deste trabalho é produzir farinhas a partir de coprodutos agroindustriais, modificar por métodos distintos (ultrassom e tratamento térmico em baixa umidade - TTBU) o amido da farinha de araruta obtida e determinar a viabilidade tecnológica e nutricional da utilização das farinhas de araruta modificadas e de coprodutos agroindustriais na produção de diferentes tipos de massas alimentícias. Foram avaliadas as propriedades de hidratação, de pasta e térmicas das farinhas cruas e modificadas. Os melhores resultados dos tratamentos com ultrassom são os com intensidade variando entre 35,83 e 62% com tempo entre 5 e 15 minutos. Já para o TTBU os melhores resultados da modificação são os que utilizaram menor temperatura (105°C) e menores tempos (15 e 30 minutos). Levando em consideração o uso das farinhas modificadas na produção de massas alimentícias, foram selecionados os tratamentos de ultrassom com parâmetros de intensidade 43,5% e tempo 15 min e TTBU com temperatura de 105°C por 15 min. Através das análises tecnológicas das massas alimentícias produzidas foi possível analisar e escolher os melhores parâmetros para se obter uma massa com menor tempo ótimo de cozimento, perda de sólidos, intermediário aumento de massa, e menores valores de firmeza, ângulo Hue e cromaticidade C*. A composição proximal das massas foi satisfatória, podendo ser caracterizada como um alimento com alto teor de proteína e alto teor de fibra, de acordo com a legislação. As massas com maior desejabilidade apresentaram uma boa aceitação sensorial. Os resultados encontrados indicam a possibilidade de se desenvolver e aperfeiçoar massas alimentícias formuladas com farinha de araruta crua e modificadas e coprodutos agroindustriais.

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