Dissertations / Theses: 'Biomage'

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Smarž, Patrik. "Využití odpadní biomasy pro výrobu elektrické energie." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221204.

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Diploma thesis, in its introduction, describes the expression biomass and the ways of its production from various sources, focused particularly on waste biomass In the following part it deals with the description of its origin and the advantages of its usage. It describes the usage of biomass in the world as well as in the Slovak Republic. It also looks into the possibilities of processing of biomass and the following use at heat and electricity production. In its last part this work describes, on particular examples, the usage of biomass in electricity and heat production, from businesses with high power to its usage in houses.

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RUNDO, LEONARDO. "Computer-Assisted Analysis of Biomedical Images." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2019. http://hdl.handle.net/10281/241343.

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Oggigiorno, la mole di dati biomedicali eterogenei è in continua crescita grazie alle nuove tecniche di sensing e alle tecnologie ad high-throughput. Relativamente all'analisi di immagini biomedicali, i progressi relativi alle modalità di acquisizione di immagini agli esperimenti di imaging ad high-throughput stanno creando nuove sfide. Questo ingente complesso di informazioni può spesso sopraffare le capacità analitiche sia dei medici nei loro processi decisionali sia dei biologi nell'investigazione di sistemi biochimici complessi. In particolare, i metodi di imaging quantitativo forniscono informazioni scientificamente rilevanti per la predizione, la prognosi o la valutazione della risposta al trattamento, prendendo in considerazione anche approcci di radiomica. Pertanto, l'analisi computazionale di immagini medicali e biologiche svolge un ruolo chiave in applicazioni di radiologia e di laboratorio. A tal proposito, framework basati su tecniche avanzate di Machine Learning e Computational Intelligence permettono di migliorare significativamente i tradizionali approcci tradizionali di Image Processing e Pattern Recognition. Tuttavia, le tecniche convenzionali di Intelligenza Artificiale devono essere propriamente adattate alle sfide uniche imposte dai dati di imaging biomedicale. La presente tesi mira a proporre innovativi metodi assistiti da calcolatore per l'analisi di immagini biomedicali, da utilizzare anche come strumento per lo sviluppo di Sistemi di Supporto alle Decisioni Cliniche, tenendo sempre in considerazione la fattibilità delle soluzioni sviluppate. In primo luogo, sono descritti gli algoritmi classici di Image Processing realizzati, focalizzandosi sugli approcci basati su regioni e sulla morfologia matematica. Dopodiché, si introducono le tecniche di Pattern Recognition, applicando il clustering fuzzy non supervisionato e i modelli basati su grafi (i.e., Random Walker e Automi Cellulari) per l'elaborazione di dati multispettrali e multimodali di imaging medicale. In riferimento ai metodi di Computational Intelligence, viene presentato un innovativo framework evolutivo basato sugli Algoritmi Genetici per il miglioramento e la segmentazione di immagini medicali. Inoltre, è discussa la co-registrazione di immagini multimodali utilizzando Particle Swarm Optimization. Infine, si investigano le Deep Neural Network: (i) le capacità di generalizzazione delle Convolutional Neural Network nell'ambito della segmentazione di immagini medicali provenienti da studi multi-istituzionali vengono affrontate mediante la progettazione di un'architettura che integra blocchi di ricalibrazione delle feature, e (ii) la generazione di immagini medicali realistiche basata sulle Generative Adversarial Network è applicata per scopi di data augmentation. In conclusione, il fine ultimo di tali studi è quello di ottenere conoscenza clinicamente e biologicamente utile che possa guidare le diagnosi e le terapie differenziali, conducendo verso l'integrazione di dati biomedicali per la medicina personalizzata. Difatti, i metodi assistiti da calcolatore per l'analisi delle immagini biomedicali sono vantaggiosi sia per la definizione di biomarcatori basati sull'imaging sia per la medicina e biologia quantitativa.
Nowadays, the amount of heterogeneous biomedical data is increasing more and more thanks to novel sensing techniques and high-throughput technologies. In reference to biomedical image analysis, the advances in image acquisition modalities and high-throughput imaging experiments are creating new challenges. This huge information ensemble could overwhelm the analytic capabilities needed by physicians in their daily decision-making tasks as well as by biologists investigating complex biochemical systems. In particular, quantitative imaging methods convey scientifically and clinically relevant information in prediction, prognosis or treatment response assessment, by also considering radiomics approaches. Therefore, the computational analysis of medical and biological images plays a key role in radiology and laboratory applications. In this regard, frameworks based on advanced Machine Learning and Computational Intelligence can significantly improve traditional Image Processing and Pattern Recognition approaches. However, conventional Artificial Intelligence techniques must be tailored to address the unique challenges concerning biomedical imaging data. This thesis aims at proposing novel and advanced computer-assisted methods for biomedical image analysis, also as an instrument in the development of Clinical Decision Support Systems, by always keeping in mind the clinical feasibility of the developed solutions. The devised classical Image Processing algorithms, with particular interest to region-based and morphological approaches in biomedical image segmentation, are first described. Afterwards, Pattern Recognition techniques are introduced, applying unsupervised fuzzy clustering and graph-based models (i.e., Random Walker and Cellular Automata) to multispectral and multimodal medical imaging data processing. Taking into account Computational Intelligence, an evolutionary framework based on Genetic Algorithms for medical image enhancement and segmentation is presented. Moreover, multimodal image co-registration using Particle Swarm Optimization is discussed. Finally, Deep Neural Networks are investigated: (i) the generalization abilities of Convolutional Neural Networks in medical image segmentation for multi-institutional datasets are addressed by conceiving an architecture that integrates adaptive feature recalibration blocks, and (ii) the generation of realistic medical images based on Generative Adversarial Networks is applied to data augmentation purposes. In conclusion, the ultimate goal of these research studies is to gain clinically and biologically useful insights that can guide differential diagnosis and therapies, leading towards biomedical data integration for personalized medicine. As a matter of fact, the proposed computer-assisted bioimage analysis methods can be beneficial for the definition of imaging biomarkers, as well as for quantitative medicine and biology.

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Ptáček, Pavel. "Teplotní pole v tuhém palivu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417431.

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The diploma thesis deals with a temperature field in a solid fuel during the combustion process. At the beginning of this thesis, research of available literature was conducted to obtain information about the composition of wood, properties affecting the combustion process, and the basics of heat transfer. Afterward, the temperature profiles of the samples were recorded during the measurement in the observation furnace. The temperature profiles of samples of six different sizes which were made of spruce and beech wood were subsequently evaluated and compared. Based on experimentally obtained data, a mathematical model was created in the OpenModellica software. Finally, the results of the mathematical model were compared with experimentally obtained data and appropriate conclusions were deduced.

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Křivák, Petr. "Návrh roštového kotle s přirozenou cirkulací na spalování slámy z pšenice,žita a ječmene." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231257.

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The aim of the thesis is the design of the steam grate boilers of 40 t/h for straw burning. The required parameters are generated steam temperature 420 ° C and a pressure of 5.5 MPa. The specified fuel is cereal straw with a calorific value of 9.5 MJ/kg. The calculation is made from the stoichiometric calculation of elemental analysis, to calculate the individual dimensions and heating surfaces of the boiler.

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Němec, Radim. "Roštový kotel s přirozenou cirkulací na spalování slámy z pšenice,žita a ječmene,20t/h." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230887.

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The aim of this thesis is to propose a grate steam boiler for combustion of straw from wheat, rye and barley output of 20 t / h The calculation is performed by stoichiometric calculation of elemental analysis to calculate the dimensions of a boiler heating surfaces. Default superheated steam can be used mainly for electricity generation.

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Silva, Beatriz Kelly Guedes da. "Disponibilidade de biomassa e caracterização da caatinga sob manejo agroecológico." Universidade Federal Rural do Semi-Árido, 2016. http://bdtd.ufersa.edu.br:80/tede/handle/tede/567.

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Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-03-09T15:24:50Z No. of bitstreams: 1 BeatrizKGS_DISSERT.pdf: 721873 bytes, checksum: 2d3282574ae4e81147c9d077f6efb0ad (MD5)
Made available in DSpace on 2017-03-09T15:24:51Z (GMT). No. of bitstreams: 1 BeatrizKGS_DISSERT.pdf: 721873 bytes, checksum: 2d3282574ae4e81147c9d077f6efb0ad (MD5) Previous issue date: 2016-07-28
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The Caatinga occupies about 11% of the national territory, covering the states of Bahia, Sergipe, Alagoas, Pernambuco, Paraiba, Rio Grande do Norte, Ceará, Piauí and Minas Gerais. Native pastures have great importance for the world's livestock, particularly for the production of small ruminants in the Northeast. This work aimed to characterize the vegetation of Caatinga under agroecologica management, the same being discussed in theoretical and scientific paper for publication. The theoretical framework is reported descriptions of the Brazilian semiarid region in which highlights the vegetation characteristics of the Caatinga with forage potential and discusses its use in periods of drought and rain over the years. Also reports agroecologica features that help comes a better handling of the animals that feed on forage species in the Caatinga, addressing floristic structuring and phytosociological characterization for sustainable management, even in periods of drought. The paper depicts the study of the availability of dry matter, floristic composition and frequency, and the similarity of species of plant areas of Caatinga under agroecologica management. In this study, it raised the availability of dry matter, which showed variations in the periods influenced by the function of vegetation resilience of rain the previous cycle, with maximum peaks of dry matter, 1.005 kg DM / 0,25m² and 1.042 kg MS / 0,25m² respectively in October and April. In that experiment it was observed that the most frequent species were Euphorbiaceae, Fabaceae, Rubiaceae and Poaceae. To evaluate the similarity of species with the highest similarity were suaveolens Mesosphaeru (lavender), Tribulus terrestris L. (bull's head), Borreria verticillata (old head), Mimosa hostilis Benth (Jurema), Sida sp (mauve) and Aristida adscensionis L. (cocksfoot grass)
A caatinga ocupa cerca de 11% do território nacional, abrangendo os Estados da Bahia, Sergipe, Alagoas, Pernambuco, Paraíba, Rio Grande do Norte, Ceará, Piauí e Minas Gerais. As pastagens nativas têm grande importância para a pecuária mundial, em especial para a produção de pequenos ruminantes do Nordeste. Esta dissertação objetivou caracterizar a vegetação da Caatinga sob manejo agroecológico, sendo o mesmo discutido em referencial teórico e um artigo cientifico para publicação. No referencial teórico é relatado descrições sobre a região semiárida brasileira no qual evidencia as características da vegetação da Caatinga com potencial forrageiro e aborda sua utilização nos períodos de seca e de chuva no decorrer dos anos. Relata ainda as características agroecológicas que vem auxiliar um melhor manejo dos animais que se alimentam de espécies forrageiras na Caatinga, abordando estruturações florísticas e fitossociológicas para caracterização de um manejo sustentável, mesmo em períodos de estiagem. O artigo científico retrata o estudo da disponibilidade de matéria seca, composição florística e frequência, e a similaridade de espécies de áreas vegetais da Caatinga sob manejo agroecológico. Nesse estudo, foi levantada a disponibilidade de matéria seca, que apresentou variações nos períodos por influência da resiliência da vegetação em função das chuvas do ciclo anterior, tendo picos de máximo de matéria seca, de 1,005 kg MS/0,25m² e de 1,042 kg MS/0,25m² respectivamente nos meses de outubro e abril. No referido experimento observou-se que as espécies mais frequentes foram as Euphorbiaceae, Fabaceae, Rubiaceae e Poaceae. Para avaliação de similaridade as espécies que apresentaram maior similaridade foram as Mesosphaeru suaveolens (alfazema), Tribulus terrestris L.(cabeça de touro), Borreria verticillata (cabeça de velho), Mimosa hostilis Benth (jurema-preta), Sida sp (malva) e Aristida adscensionis L. (capim panasco)
2017-03-09

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Guillot, Marie. "Etude du traitement de la biomasse par voie hydrothermale pour la récupération de molécules et de minéraux à haute valeur ajoutée." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20218/document.

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La croissance démographique mondiale, associée à une augmentation générale du niveau de vie, se traduit par l'explosion des besoins en matières premières et énergie. Afin de relever ce défi, une attention accrue est accordée aux énergies et ressources naturelles renouvelables. Parmi elles, la biomasse est particulièrement prometteuse. Elle présente des avantages certains (abondance, répartition homogène) mais aussi plusieurs inconvénients (faible densité énergétique, humidité élevée,…). Pour surmonter ces difficultés, la torréfaction est la méthode la plus connue, mais elle induit une augmentation des taux de cendres et une perte de matière. La carbonisation hydrothermale (HTC) est une alternative possible. L'objet de cette thèse est l'étude de la HTC comme moyen de bonifier la biomasse lignocellulosique. Trois axes principaux ont été considérés: augmentation de la densité énergétique, récupération de molécules, et minéraux d'intérêt. L'étude porte d'abord sur la HTC de systèmes moléculaires représentatifs de ceux présents dans le bois. Le hêtre a été étudié comme biomasse modèle, permettant de déterminer des conditions expérimentales optimales, appliquées ensuite à diverses biomasses. Enfin d'autres méthodes d'activation ont été testées telles que les micro-ondes et les fluides supercritiques. Les hydrochars obtenus après HTC présentent une diminution concomitante des ratios atomiques H/C et O/C. La phase liquide contient différentes molécules d'intérêt (furfural,…). Enfin, les teneurs en cendres diminuent après HTC du fait d'une lixiviation partielle de certains éléments (alcalins et alcalino-terreux). En conclusion, la HTC semble être une alternative intéressante à la torréfaction ; elle permet la production d'hydrochars avec des teneurs élémentaires adaptées à une utilisation en gazéification et la récupération de molécules et minéraux. L'intérêt et la faisabilité technique ont été démontrés en particulier sur des biomasses humides (plantes agricoles) ou polluées (broyats de déchetterie)
Population growth, coupled with a general increase in standard of living, result in a booming demand for raw material and energy. To face this challenge, an increased attention is paid to the use of renewable energies and natural resources. Among them, biomass is especially promising. Its advantages (abundance, distribution all over the Earth) are balanced by several drawbacks (low energy density, high moisture content,…). To overcome these problems, torrefaction is the most traditional way, but it has some inconveniences (increased ash content, loss of material). Hydrothermal carbonisation (HTC) is a possible alternative. The purpose of this thesis is the study of HTC a means to beneficiate the lignocellulosic biomass. Three main aims were identified: increase of the energy density, recover molecules and minerals of interest. The study initially focused on HTC of molecular model systems present in wood. Beech wood was also studied, as a model biomass. This study allowed determining optimal experimental conditions for treatment of further biomasses. Finally, other activation methods have been tested, such as microwaves, and supercritical fluids. Hydrochars obtained after HTC feature a concomitant decrease of the atomic H/C and O/C ratios. Liquid phase contains different molecules of interest (furfural,…). Finally, ash content decreases after HTC owing to a partial leaching of some elements (alkali and alkaline earth metals). In conclusion, HTC seems to be an interesting alternative to torrefaction as it allows for the production of hydrochars suitable for gasification, and the recovery of molecules and minerals of interest. The interest and technical feasibility have been demonstrated in particular for biomasses with high moisture (agricultural crops) or with high pollutant contents (grounds of waste disposal)

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Kalina, Jacek. "Analiza i optymalizacja układów technologicznych energetyki rozproszonej zintegrowanych z termicznym zgazowaniem biomasy." Praca habilitacyjna, Wydawnictwo Politechniki Śląskiej, 2013. https://delibra.bg.polsl.pl/dlibra/docmetadata?showContent=true&id=18846.

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Guerini, Filho Marildo. "Estimativas de variáveis biofísicas de vegetação campestre sob manejo pastoril por meio de sensoriamento remoto." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/185286.

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O Bioma Pampa representa aproximadamente 63% do território do Estado do Rio Grande do Sul - Brasil caracteriza-se pela alta biodiversidade de espécies vegetais e por sua formação predominantemente campestre. Em função da contínua incorporação de espécies exóticas, monoculturas e a práticas por vezes inadequadas de manejo pastoril para produção pecuária, os campos do Bioma Pampa estão rapidamente sendo degradados, fragmentados e descaracterizados. A Biomassa é uma das variáveis biofísicas estratégicas de interesse em estudos de controle, monitoramento e estimativas da vegetação campestre. O objetivo principal deste estudo é contribuir no desenvolvimento de novas estratégias de manejo e monitoramento adequados da vegetação campestre e inferir regressão linear multivariada para estimar a biomassa dos campos nativos a partir de dados remotos e dados de campo. As avaliações foram realizadas em área pertencente à Universidade Federal de Santa Maria, localizada na região central do Rio Grande do Sul. Os manejos pastoris correspondem a duas somas térmicas acumuladas, em dias, de 375 e 750 graus-dias (GD), que determinaram os intervalos entre pastoreio. Os dados remotos utilizados foram oriundos de imagem MSI do Satélite Sentinel-2 e dados de espectrorradiômetro com amplitude de 350-2500 nm. Verificou-se que as duas técnicas apresentaram resultados satisfatórios, em que inferiu-se regressões com r²ajustado = 0.65 para estimar biomassa verde e regressões com r²ajustado = 0.61 para biomassa total e biomassa senescente. Desta forma, o estudo verificou que é possível minimizar os esforços de campo para auxiliar no monitoramento, organização e conservação dos campos nativos do Bioma Pampa utilizando dados de sensoriamento remoto como ferramenta de manejo buscando a sustentabilidade destes complexos ambientes naturais.
The Pampa Biome represents approximately 63% of the territory in the State of Rio Grande do Sul - Brazil, characterized by the high biodiversity of plant species and its predominantly rural formation. As a result of the continuous incorporation of exotic species, monocultures and excessive cattle production, the Pampa Biome fields are rapidly being degraded, fragmented and decharacterized. Biomass is one of the strategic biophysical variables of interest in studies of prevention, monitoring and estimates of the country vegetation. The main objective of this study is to contribute to the development of new strategies for the proper management and monitoring of the country vegetation and to infer multivariate linear regression to estimate the biomass of the natural grassland in native fields from remote data and field data. The evaluations were carried out in an area belonging to the Federal University of Santa Maria, located in the central region of Rio Grande do Sul. Pastoral management correspond to two accumulated thermal sums in days of 375 and 750 degrees-days (GD), which determined the intervals between grazing. The remote data used came from MSI image of Sentinel-2 Satellite and spectroradiometer data with amplitude of 350-2500 nm. It was verified that the two techniques presented satisfactory results, in which regressions with adjusted r² of 0.65 were estimated to estimate green biomass and regressions with adjusted r²> 0.61 for total biomass and dry biomass. In this way, the study verified that it is possible to minimize the field efforts to assist in the monitoring, organization and conservation of the natural grassland in native fields of the Pampa Biome using remote sensing data as a management tool seeking the sustainability of these complex natural environments.

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Juřena, Tomáš. "CFD modelování hoření tuhých paliv na roštu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228327.

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Práce je zaměřena na vytvoření numerického modelu 1D experimentálního reaktoru pro spalování tuhých paliv. Metodou konečných objemů je provedena diskretizace řídících rovnic a takto formulovaná úloha je implementována do programu v prostředí MATLAB. V závěru jsou uvedeny výsledky několika simulací hoření slámy.

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Bubeníková, Pavlína. "Ekonomické aspekty environmentálního chování MSP." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-11870.

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woodenThe Energetic consumption of each kind of energy grows with the development of society and industrialization. Major influence has the world population, which is having growing tendencies. The most important source of primary energy is the rock-oil, the second important source of energy is coal, followed by natural gas. Regarding to the fact that these commodities cannot be renewed, it is clear that it can be uncontrollably wasted. There is emerging a space for new possibilities such as the energy of future -- renewable sources of energy, which are taking the fourth place in the importance of the world and it's energy sources. It is mainly biomass, water, solar or wind energy. This diploma thesis is aiming at the production of biomass -- pellets, which are a biological source of energy (wooden or vegetative material) with number of positive features and parameters. The main objective of this diploma thesis is to offer excursion into another space of modern thinking, which is well-founded by economical facts and also explains the need of taking into the consideration other alternative energetic types, which should be a common thing in future.

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Kincl, Karel. "Potential of Biomass and Biogas Energy Projects in the Czech Republic." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-73156.

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The aim of my Master Thesis is to provide the reader a holistic picture about the current situation on the renewable energy market, specifically in the area of biomass energy. Firstly, the complex research, which had been conducted by the European Union, Czech government and individual research groups, was examined to make a comprehensive overview about the Czech energy mix of renewable sources. Secondly, the biomass energy fundamentals were elaborated in more details to provide the reader solid insights into the biomass origins, methods of energy conversion as well as its current market circumstances. Next, the financing structure of biomass energy projects together with SWOT analysis on biomass was conducted based on the personal work experience from the Department of Renewable Energy Financing at xxxxxxxxxx bank and the available analytical materials. Consequently, the recommendations for potential biomass investors were concisely described together with the market prediction and possible outlook that was suggested based on the previous analysis.

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Tuček, Jan. "Návrh kogenerační jednotky s výkonem 200 kWe s dodávkou tepla pro sušárnu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231388.

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In this diploma thesis "Cogeneration unit with output 200 kWe" the first part describes the properties, drying and combustion of biomass. The next section deals with the description of the combined production of electricity and thermal energy and gas turbines. In the last part of the diploma thesis is devoted to the design and calculations of thermal cycle in order to achieve maximum efficiency.

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Salami, Najdat. "Gasification of Pine Wood Chips with Air-Steam in Fluidized Bed." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-234253.

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Tato práce studovala vliv použití vzduchu a páry jako zplynovacího činidla ve zkapalňovacím generátoru plynu na vlastnosti vyprodukovaného plynu (oxid uhelnatý, vodík, obsah dehtu a nízká výhřevnost). Tato studie byla založena na experimentech které byly provedeny ve fluidním generátoru plynu Biofluid 100 v laboratoři Energetického ústavu technologické univerzity Brno s použitím páry jako zplynovacího činidla a borovicového dřeva jako výchozí suroviny. Cílem této dizertační práce je stanovit nejlepší provozní parametry systému při užití vodní páry a vzduchu ve zplynovacím zařízení biofluid 100, při kterých se dosáhne nejvyšší kvality plynu. K dosažení tohoto cíle bylo provedeno mnoho experimentů studujících účinky teploty reaktoru(T101), poměru páry a biomasy (S/B) poměru páry a vzduchu (S/A), teploty dodávané páry (Tf1), ekvivalentního poměru ER,ve složení vyprodukovaném plynu, výhřevnost, výtěžnost plynu, efektivnost přeměny uhlíku a účinnost zplynovače. Výsledky experimentů ukázaly, že zvýšení teploty reaktoru vede ke zvýšení obsahu vodíku a oxidu uhelnatého, výhřevnosti, výtěžnosti plynu, efektivnosti přeměny uhlíku, efektivnosti zplynovače a ke snížení obsahu dehtu. Příliš vysoká teplota reaktoru ale snižuje výhřevnost plynu. Dodáváním páry se zvýšila kvalita plynu, vyšší H_2,LHV a nižší obsah dehtu. Přesto ale nadměrné množství páry snižuje zplyňovací teplotu a tím i kvalitu plynu. Poměr páry a biomasy při kterém se dosáhne nejlepší kvality plynu se zvýší s teplotou reaktoru. Bylo zjištěno, že kdykoli byla teplota páry (Tf1) vyšší, byl plyn více kvalitní, ale zvyšování teploty páry také zvyšuje ekonomické náklady na vyprodukovaný plyn což se při masové produkci plynu musí brát v úvahu. Efekt ekvivalentního poměru ER, byl studován postupným zvyšováním, bylo zjištěno, že nejlepší ekvivalentní poměr pro dosažení nejvyšší kvality plynu byl kolem 0.29, při ER > 0.29 byl obsah hořlavého plynu snížen a to vedlo ke snížení kvality plynu. Obsah dehtu se snižuje jak zvýšením teploty reaktoru tak poměrem páry k biomase. Podle výsledků experimentů a diskuze, bylo zjištěno, že při použití směsi páry a vzduchu se kvalita plynu zvýší, parametry pro dosažení nejvyšší kvality vyprodukovaného plynu při experimentálních podmínkách jsou: T101 =829 S/B=0.67((kg steam)/(kg biomass)) ,S/A=0.67((kg steam)/(kg air)) , ER= 0.29 and a Tf1 je nejvyšší možná teplota,při které se vodík zvýší z 10.48 na 19,68% a výhřevnost z 3.99 na 5.52(MJ/m^3 ) a obsah dehtu z 1964(mg/m^3 ) na 1046(mg/m^3 ) zvýšením z 0 na 0.67 při T101=829 .

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Steinbrück, Johannes [Verfasser], and H. [Akademischer Betreuer] Bockhorn. "Biomass Steam Processing - Konzeption und Entwicklung eines Verfahrens zur Karbonisierung von Biomasse / Johannes Steinbrück ; Betreuer: H. Bockhorn." Karlsruhe : KIT-Bibliothek, 2019. http://d-nb.info/1200471288/34.

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Moskalík, Jiří. "Návrh metod čištění plynu při zplyňování stébelnin." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-234187.

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Due to the continuous growth of energy consumption it is required that development in the energy sector is focused on renewable energy sources. Another possibility how to reduce the consumption of primary energy resources is also searching for new and non-traditional fuels. The biomass is the best and potentially expandable renewable energy source in geographic conditions in the Czech Republic. The energy usage of biomass has experienced a significant increase in recent years, however, even in the big energy power plant. This increase in consumption made mainly from wood biomass a shortage fuel, and it began to raise its price. The consumers of biomass fuel are starting to look for a different type of fuel at this time. Stalk and slightly contaminated biomass are representatives of these non-traditional fuels. Stalks are mostly annual plants grown primarily for subsistence. Waste parts of these plants can be utilized for production of energy. The characteristic temperatures of stalk ash have relatively low values. Sintering of ash in a device is one of the obstacles for energy usage of stalk. Sintering of ash brings a number of operational problems at power facilities. Therefore, the part of a research is dedicated to the melting of ash. The thermal gasification is one of the possibilities how to use biomass efficiently. Gasification can be understood as the thermo-chemical conversion of solid fuel into a different state, in this case the gaseous state. The combustion process is generally more manageable for gaseous fuels. Due to this process ower emissions of undesirable compounds at the output of the combustion device can be achieved. Thermal gasification process takes place under stochiometric access of oxidant. The gas with low heating value is on the outlet from gasification process. The main components of produced gas are hydrogen, carbon monoxide and methane. The final gas contains also a lot of undesirable constituents, which make this gas disadvantaged in energy. These constituents are neutral components that dilute gas only, and pollutants as dust, tar and compounds of sulfur and chlorine. These pollutants complicate further use of the generated gas. The tar compounds together with dust causing build-up on the conveyor pipe and also on the combustion equipment, which are using this generated gas. The quality of produced gas is increases by another reprocessing and cleaning. The purified gas can be used for cogeneration of energy and burn it in internal combustion engines or gas turbines. Other possibility is typical usage for heating according to the needs of technology. The atmospheric fluidized bed gasification reactor Biofluid 100th was built for experimental purposes in the laboratories of the Energy Institute. The thesis is focused on thermal gasification of stalk and other non-traditional fuels in Biofluid device. The aim is to achieve a stable gasification process of stalk and thereby verify the possibility of stalk use as fuel for technology Biofluid. Subsequent aim is design of methods for cleaning the raw gas from the tar compounds. The research is focused on the secondary gas cleaning methods due to the requirements of high purity of the resulting gas.

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Becek, Kazimierz. "Biomass Representation in Synthetic Aperture Radar Interferometry Data Sets." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-62707.

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This work makes an attempt to explain the origin, features and potential applications of the elevation bias of the synthetic aperture radar interferometry (InSAR) datasets over areas covered by vegetation. The rapid development of radar-based remote sensing methods, such as synthetic aperture radar (SAR) and InSAR, has provided an alternative to the photogrammetry and LiDAR for determining the third dimension of topographic surfaces. The InSAR method has proved to be so effective and productive that it allowed, within eleven days of the space shuttle mission, for acquisition of data to develop a three-dimensional model of almost the entire land surface of our planet. This mission is known as the Shuttle Radar Topography Mission (SRTM). Scientists across the geosciences were able to access the great benefits of uniformity, high resolution and the most precise digital elevation model (DEM) of the Earth like never before for their a wide variety of scientific and practical inquiries. Unfortunately, InSAR elevations misrepresent the surface of the Earth in places where there is substantial vegetation cover. This is a systematic error of unknown, yet limited (by the vertical extension of vegetation) magnitude. Up to now, only a limited number of attempts to model this error source have been made. However, none offer a robust remedy, but rather partial or case-based solutions. More work in this area of research is needed as the number of airborne and space-based InSAR elevation models has been steadily increasing over the last few years, despite strong competition from LiDAR and optical methods. From another perspective, however, this elevation bias, termed here as the “biomass impenetrability”, creates a great opportunity to learn about the biomass. This may be achieved due to the fact that the impenetrability can be considered a collective response to a few factors originating in 3D space that encompass the outermost boundaries of vegetation. The biomass, presence in InSAR datasets or simply the biomass impenetrability, is the focus of this research. The report, presented in a sequence of sections, gradually introduces terminology, physical and mathematical fundamentals commonly used in describing the propagation of electromagnetic waves, including the Maxwell equations. The synthetic aperture radar (SAR) and InSAR as active remote sensing methods are summarised. In subsequent steps, the major InSAR data sources and data acquisition systems, past and present, are outlined. Various examples of the InSAR datasets, including the SRTM C- and X-band elevation products and INTERMAP Inc. IFSAR digital terrain/surface models (DTM/DSM), representing diverse test sites in the world are used to demonstrate the presence and/or magnitude of the biomass impenetrability in the context of different types of vegetation – usually forest. Also, results of investigations carried out by selected researchers on the elevation bias in InSAR datasets and their attempts at mathematical modelling are reviewed. In recent years, a few researchers have suggested that the magnitude of the biomass impenetrability is linked to gaps in the vegetation cover. Based on these hints, a mathematical model of the tree and the forest has been developed. Three types of gaps were identified; gaps in the landscape-scale forest areas (Type 1), e.g. forest fire scares and logging areas; a gap between three trees forming a triangle (Type 2), e.g. depending on the shape of tree crowns; and gaps within a tree itself (Type 3). Experiments have demonstrated that Type 1 gaps follow the power-law density distribution function. One of the most useful features of the power-law distributed phenomena is their scale-independent property. This property was also used to model Type 3 gaps (within the tree crown) by assuming that these gaps follow the same distribution as the Type 1 gaps. A hypothesis was formulated regarding the penetration depth of the radar waves within the canopy. It claims that the depth of penetration is simply related to the quantisation level of the radar backscattered signal. A higher level of bits per pixels allows for capturing weaker signals arriving from the lower levels of the tree crown. Assuming certain generic and simplified shapes of tree crowns including cone, paraboloid, sphere and spherical cap, it was possible to model analytically Type 2 gaps. The Monte Carlo simulation method was used to investigate relationships between the impenetrability and various configurations of a modelled forest. One of the most important findings is that impenetrability is largely explainable by the gaps between trees. A much less important role is played by the penetrability into the crown cover. Another important finding is that the impenetrability strongly correlates with the vegetation density. Using this feature, a method for vegetation density mapping called the mean maximum impenetrability (MMI) method is proposed. Unlike the traditional methods of forest inventories, the MMI method allows for a much more realistic inventory of vegetation cover, because it is able to capture an in situ or current situation on the ground, but not for areas that are nominally classified as a “forest-to-be”. The MMI method also allows for the mapping of landscape variation in the forest or vegetation density, which is a novel and exciting feature of the new 3D remote sensing (3DRS) technique. Besides the inventory-type applications, the MMI method can be used as a forest change detection method. For maximum effectiveness of the MMI method, an object-based change detection approach is preferred. A minimum requirement for the MMI method is a time-lapsed reference dataset in the form, for example, of an existing forest map of the area of interest, or a vegetation density map prepared using InSAR datasets. Preliminary tests aimed at finding a degree of correlation between the impenetrability and other types of passive and active remote sensing data sources, including TerraSAR-X, NDVI and PALSAR, proved that the method most sensitive to vegetation density was the Japanese PALSAR - L-band SAR system. Unfortunately, PALSAR backscattered signals become very noisy for impenetrability below 15 m. This means that PALSAR has severe limitations for low loadings of the biomass per unit area. The proposed applications of the InSAR data will remain indispensable wherever cloud cover obscures the sky in a persistent manner, which makes suitable optical data acquisition extremely time-consuming or nearly impossible. A limitation of the MMI method is due to the fact that the impenetrability is calculated using a reference DTM, which must be available beforehand. In many countries around the world, appropriate quality DTMs are still unavailable. A possible solution to this obstacle is to use a DEM that was derived using P-band InSAR elevations or LiDAR. It must be noted, however, that in many cases, two InSAR datasets separated by time of the same area are sufficient for forest change detection or similar applications.

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Sudholt, Alena [Verfasser]. "Ignition and Combustion of Tailor-Made Fuels from Biomass : Zündverhalten und Verbrennung maßgeschneiderter Kraftstoffe aus Biomasse / Alena Sudholt." Aachen : Shaker, 2017. http://d-nb.info/1124366644/34.

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Meyer, Victoria. "De la canopée à la biomasse : télédétection lidar des dynamiques de la forêt tropicale à différentes échelles." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30028.

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L'estimation précise da la biomasse des forêts tropicales est un enjeu important pour des programmes tels que REDD+ et autres politiques environnementales. Cette thèse étudie comment des métriques lidar aident à estimer la biomasse aérienne (AGB) et suit trois axes: le premier chapitre traite de la détection de la dynamique des forêts. Nous explorons quelle échelle/résolution/taille de parcelle et quelles métriques lidar sont optimales pour estimer la biomasse et ses dynamiques. Nous avons trouvé qu'une résolution d'au moins un hectare et la hauteur de canopée moyenne donnent les meilleurs résultats. Le deuxième chapitre traite des dynamiques spatiales et compare neuf sites situés dans les Néotropiques. Nous présentons une nouvelle métrique représentant l'aire des larges canopées (LCA), couplée avec la densité de bois moyenne des sites pour estimer leur biomasse. Nous montrons ainsi que les différences entre sites peuvent être dépassées et qu'un seul modèle peut être utilisé pour estimer leur biomasse. Enfin, le troisième chapitre présente la carte de biomasse d'une région méconnue et peu étudiée de Colombie, obtenue à partir d'un algorithme d'apprentissage automatique combinant des données lidar, de terrain, et des données satellitaires. Les trois chapitres soulignent l'importance d'identifier les différentes sources d'erreur et les incertitudes liées au processus d'estimation de biomasse. Ce travail représente une avancée dans l'étude du lidar en étant le premier à avoir estimé les dynamiques de biomasse en utilisant des instruments différents en forêt tropicale et à avoir produit la première carte de biomasse d'une région, comblant ainsi un vide qui existait sur la connaissance des forêts de Colombie
Accurate estimation of biomass in tropical forests is of prime importance for programs such as REDD+ and for environmental policy in general. This thesis studies how lidar metrics can derive aboveground biomass (AGB) accurately and follows three axes : the first chapter deals with change detection of forest dynamics. It explores what scale/resolution/field plot size as well as which lidar-metrics are best to estimate AGB and AGB changes. We found that a resolution of at least 1ha and the mean canopy height metric give better results. The second chapter deals with spatial dynamics and compares nine sites in the Neotropics. We introduce a new metric representing large canopy area (LCA), coupled with mean wood density, to estimate AGB across sites and show that differences between sites can be overcome. Finally, our last chapter introduces a regional biomass map of a poorly known region of Colombia, using a machine learning algorithm combining airborne lidar data, field data and spaceborne remote sensing data. The three chapters emphasize on the importance of identifying sources of error and uncertainties. This work represents an advance in lidar studies by being the first one to estimate biomass changes using different sensors in tropical forests, exploring a new area and filling a gap in the knowledge of tropical forests of Colombia

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Lê, Thành Kim. "Espèces condensables issues de torréfaction de biomasses lignocellulosiques : caractérisation aux échelles laboratoire et pilote." Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/14717/1/lethanh.pdf.

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La torréfaction est un traitement thermique opéré entre 200 et 300 °C en atmosphère inerte améliorant certaines propriétés de la biomasse, afin d’utiliser celle-ci comme biocombustible. Nos travaux portent spécifiquement sur la caractérisation des espèces condensables produites en torréfaction, aux échelles laboratoire et pilote. En laboratoire, des échantillons de pin, frêne, miscanthus et paille de blé ont été torréfiés à 250, 280 et 300 °C en réacteur à lit fixe. Les espèces condensables ont ensuite été analysées par GC-MS, GC-GC et HPLC-MS. Cette analyse a permis d’identifier une centaine d’espèces, dont une vingtaine, quantifiée, représente 77 % des condensables. À l’échelle pilote, un réacteur continu a été conçu, amélioré et caractérisé pour torréfier quelques kg.h-1 de biomasse. Un système de récupération multi-étagée des condensables a été développé. Des essais de torréfaction ont montré que les fractions condensées présentent des compositions chimiques différentes.

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Forgacz, Claire. "Elaboration de matériaux poreux à partir de sous-produits de la biomasse par polymérisation d’émulsions concentrées." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14435/document.

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Cette thèse est dédiée à l'élaboration de matériaux poreux par polymérisation d'émulsion concentrées à partir de polymères issus de la biomasse. La méthodologie polyHIPE a été adaptée pour mettre en œuvre un sous-produit de l'industrie papetière : la liqueur noire Kraft. Des matériaux poreux et possédant une structure interne modulable par les paramètres d'émulsification, ont été obtenus
This project is dedicated to the synthesis of porous materials from biopolymers via an emulsion-templated polymerisation. The polyHIPE synthesis was adaptated to the physico-chemical properties of the main by-product of the paper industry : the Kraft black liquor. Porous material was obtained and their morphological caracteristics can be modulated through the emulsification parameters

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Monsigny, Louis. "Catalyseurs d’hydrosilylation pour la réduction de liaisons C-O dans les polymères oxygénés." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS026/document.

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L’objectif principal de cette thèse a été de développer de nouveaux systèmes catalytiques efficaces pour la dépolymérisation de la biomasse et des plastiques. La stratégie choisie pour favoriser cette transformation a été l’hydrosilylation de liaisons C-O. Le catalyseur d’iridium(III) de Brookhart s'est révélé particulièrement efficace pour l’hydrosilylation la lignine conduisant à des produits aromatiques purs avec des rendements très élevés. Il a également été utilisé pour la dépolymérisation réductrice de plastiques oxygénés qui ont permis d’isoler les monomères et des composés de haute valeur ajoutée.Dans un second temps, une dépolymérisation plus « verte » de polycarbonates et de polyesters a été mise en œuvre. Celle-ci ne fait intervenir ni métaux ni solvant grâce à l’utilisation du fluorure de tetra-n-butyle amonium comme catalyseur. Enfin, l’uranium appauvri, considéré comme un déchet de l’industrie nucléaire, a été valorisé comme catalyseur pour la réduction des liaisons C-O. Il a été découvert qu’un complexe de triflate d'uranyle favorisait efficacement le couplage réducteur de l'aldéhyde en présence d'hydrosilanes conduisant à l'éther symétrique
The main objective of this thesis is the development of new efficient catalytic systems for the depolymerization of biomass and plastics. The chosen strategy to promote such transformations was the hydrosilylation of C-O bonds. Brookhart's iridium(III) catalyst was found to be very effective for hydrosilylation of lignin leading to pure aromatic products isolated in very high yields. It was also used for the reductive depolymerization of oxygenated plastics, allowing the isolation of monomers and valuable chemicals.In a second step, a "greener" depolymerization of polycarbonates and polyesters was implemented. This does not involve metals or solvents through the use of tetra-n-butyl amonium fluoride as a catalyst for hydrosilylation. Finally, depleted uranium, considered as a waste product of the nuclear industry, was valorized as a catalyst for the reduction of C-O bonds. It has been discovered that a uranyl(VI) triflate complex efficiently promotes reductive coupling of the aldehyde in the presence of hydrosilanes leading to symmetric ethers

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Le, Brech Yann. "Analyse des mécanismes primaires de pyrolyse de la biomasse." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0106/document.

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La pyrolyse est le premier mécanisme intervenant dans tous les procédés de conversion thermochimique des solides (combustion, gazéification, pyrolyse). C’est également le plus important, car il contrôle la répartition et la composition des trois types de produits : gaz, charbon, goudrons. La prédiction des produits de pyrolyse et est primordiale pour le développement de procédés de conversion thermochimique. De nombreuses études analytiques ont été réalisées mais la grande hétérogénéité des biomasses étudiées et des conditions de pyrolyse utilisées rend actuellement difficile une approche globale des mécanismes. L’objectif de cette étude a été de réaliser des analyses complémentaires de produits de pyrolyse formés pour une large gamme de températures (200°C à 500°C) en pyrolyse lente (5 K/min) pour différentes biomasses (miscanthus, chêne et douglas) à l’aide d’un lit fixe permettant un contrôle optimal des phénomènes de transfert de chaleur et de matière. De nombreuses méthodes physico-chimiques ont été utilisées pour caractériser les produits formés afin de réaliser un bilan global des mécanismes chimiques de dégradation : Résonance magnétique nucléaire (RMN) du proton 1H et du carbone 13C ; Calorimétrie (DSC) ; Thermogravimétrie ; GC/MS (Gas Chromatography and Mass spectrometry), LC/MS (Liquid Chromatography and Mass Spectrometry) et spectrométrie de masse à ionisation douce (Single Photo Ionisation SPI). Des techniques originales d’analyses dites ex-situ telles que l’analyse 2D RMN par la méthode HETCOR (Heteronuclear correlation) 1H-13C ainsi que des analyses in-situ en RMN 1H Haute Température ont été mises en place
Current research studies focus on biomass thermochemical conversion to produce other energetic vectors more appropriate to be conveyed, such as electricity, gas or liquid products. Pyrolysis is the first mechanism occurring in all thermochemical processes for solid fuels conversion (combustion, gasification, pyrolysis). It controls in a large extent products (gas, condensables and char) distribution and composition. The prediction of pyrolysis products and the understanding of the chemical mechanisms are thus pivotal for developing thermochemical reactors. Extensive work has been conducted for more than one century but the important heterogeneity of biomasses and pyrolysis conditions make it difficult to encompass a global chemical mechanism. The aim of this study is to develop complementary analyses of pyrolysis products. Pyrolysis is conducted in a fixed bed reactor under slow pyrolysis conditions (5 K/min), for a wide range of final temperature (200°C and 500°C) and for different biomasses (miscanthus, douglas and oak). Various analytical methods have been used in order to characterise the pyrolysis products: nuclear magnetic resonance (carbon 13C and proton 1H NMR), Calorimetry, Thermogravimetry, GC/MS (Gas Chromatography and Mass spectrometry), LC/MS (Liquid Chromatography and Mass Spectrometry) and soft ionization mass spectrometry (Single Photo Ionisation SPI). Original analytical methods such as 2D NMR HETCOR 1H-13C (for the analysis of chemical moieties in char) and high temperature 1H NMR (for in-situ analysis of mobile protons) have been used. The latter allowed a novel characterization of the interaction between biomass and minerals during pyrolysis

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Majcherek, Michał. "Rola doradztwa rolniczego w produkcji i wykorzystaniu biomasy energetycznej jako surowca dla biogazowni rolniczych funkcjonujących w województwie kujawsko-pomorskim." Rozprawa doktorska, Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy, 2017. http://dlibra.utp.edu.pl/Content/1103.

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Celem pracy była ocena wpływu doradztwa rolniczego na producentów i przetwórców biomasy energetycznej pochodzenia rolniczego jako surowca do produkcji w biogazowni rolniczej w województwie kujawsko-pomorskim, w całym łańcuchu dostaw od rolników aż do zakładu wytwarzającego energię z biomasy
The main aim of the present dissertation was to assess the impact of farm advisory services on producers and processors of energy biomass from agriculture as a raw material for production at an agricultural biogas plant in the Kujawsko-Pomorskie province in the entire supply chain from a farmer through to a plant producing energy from biomass
Streszcz. ang

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Doležal, Tomáš. "Business Plan: The Development and Operation of Biomass Power Plant." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-125031.

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The goals of this thesis are to create a comprehensive business plan manual from various business plan frameworks and to clarify project documentation necessary for the commencement of the biomass power plant. The theoretical part serves to the reader as a manual, how to write a business plan. In each section the thesis lists necessary questions to be answered, the theory and the recommendations what to include in the business plan. The practical part represents a complete business plan of the development and op-eration of the biomass power plant with focus on the political analysis, key resources and financial analysis. In the end of the thesis the investment decision criteria are pre-sented together with the risks analysis, providing a solid information base upon which a potential investor can decide, whether to invest into the project.

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Floková, Kateřina. "Zjednodušené výpočtové modelování spalování biomasy na roštu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229949.

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The aim of this thesis is to assemble simplified computational 3D model for straw grate combustion, based on data provided by detailed computational 1D model. This thesis is organized as follows. Firstly, current state of CFD grate combustion modelling is described. The main body of this thesis is focused on creation simplified 3D model, which includes pressure losses calculation, aproximation of data provided by outcomes of detailed 1D model and analysis of heat transfer during combustion process. Simulation results dealing with radiation heat transfer and heat conductivity are included in conclusion.

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Pajoum, Shariati Farshid. "Etude de la viabilité et de la réactivité d'une biomasse épurative de Bioréacteur à membranes." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20265.

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Les règlements plus stricts pour les rejets d'eaux usées présentent de nouveaux défis technologiques pour le traitement d'eaux usées urbaines et industrielles. Le besoin notamment d‘améliorer la qualité hygiénique de l'eau traitée se fait ressentir en cas de sites sensibles ou de réutilisation. Le bioréacteur à membranes (BRMs) représente une des approches les plus innovatrices pour éviter la présence d'agents pathogènes dans l‘eau en sortie de station. En utilisant des membranes avec un seuil de coupure dans la gamme 0.04~0.2 μm, les bactéries mais aussi les virus sont pratiquement complètement retenus. Si l'encrassement membranaire reste un problème déterminant pour le développement des BRMs, le manque d‘outils de caractérisation en ligne de la qualité et la quantité de biomasse active dans les réacteurs reste un point important pour favoriser le contrôle et l‘optimisation des BRMs. Dans cette étude une méthode originale a été développée pour évaluer la viabilité des boues activées présentes dans un réacteur biologique d‘épuration en complémentarité des informations données par la mesure d'activité respirométrique. Cette méthode permet la distinction entre cellule morte et vivante, la respirométrie pouvant alors distinguée la part active de la biomasse vivante. Le travail expérimental a été conduit dans deux réacteurs biologiques de type chenal d‘oxydation équipés de membranes immergées "airlift oxidation ditch membrane bioreactor" (AOXMBR). Les modules membranaires sont immergés dans un zone aérée où l‘apport d‘air permet à la fois la circulation d‘eau par air-lift, l‘aération du milieu et le nettoyage des membranes par aération. Les essais ont été conduits en mode fermé (batch reactor), alterné (fed batch reactor) et continu. La première partie de l‘étude concerne la caractérisation hydrodynamique du réacteur déterminante en terme de conformité du système pour la circulation des fluides, l‘intensité des transferts et des réactions d‘épuration. Les résultats mettent en avant le rôle de la géométrie de l‘airlift sur la circulation des fluides mais aussi la rétention gazeuse déterminante en terme de transfert d‘oxygène et capacité de nettoyage des membranes. La viabilité et l'activité respirométrique de boues activée ont alors été étudiées sous différentes conditions opératoires. Les résultats ont montré une évolution semblable des deux paramètres en fonction des conditions imposées. Ceci confirme l‘intérêt de la mesure de viabilité qui peut être conduite en ligne sur le système, à la différence de la mesure par respirométrie qui nécessite une procédure spécifique plus ou moins complexe. Toutefois, les essais ont montré aussi qu‘une concentration en biomasse importante était nécessaire dans le bioréacteur pour que la viabilité soit mesurable. Les résultats ont aussi montré que la viabilité et l'activité augmentent avec la charge organique (Cv). Cette variation était conforme à l'augmentation des matières volatiles en suspension MVS et de la vitesse de consommation d‘oxygène OUR. Lors de diminution de charge organique, la concentration de protéine dans le milieu a changé inversement avec la viabilité de la biomasse. De possibles améliorations de l'instrument de mesure en ligne de la viabilité et de l'activité de boues activées dans les bioréacteurs sont également discutées. Les performances épuratives mesurées ont confirmé la grande capacité épuratoire d‘un BRM, toutefois, travailler à très forte charge engendre une dynamique de colmatage intense qu‘il faut maîtriser
In this study a novel method was developed to assess the viability of activated sludge present in a biological treatment process and signify its complementarity from respirometric activity. This method allows the distinction between viable vs. dead and inactive vs. active microbial cells in biomass population and can be used for a better and more efficient control of the biological activity especially in MBR systems.For this purposed two airlift oxidation ditch membrane bioreactors (AOXMBR), were designed and constructed. They were equipped with flat sheet, membranes directly immersed in the airlift section where the air injection induced sludge aeration, water circulation and continuous membrane cleaning.To evaluate the relevance of the batch, fed-batch and AOXMBR) were carried out in order to obtain a better understanding of biomass characteristic for MBR performance.Firstly, for determining the treatment capacity of the proposed AOXMBR is important to understanding of the hydrodynamic characteristics of the system. And impact of design parameter on hydrodynamic characterization of the system was investigated. The results showed the gas holdup and liquid velocity increased with increase in superficial gas velocity and decrease in distance from aeration zone. Furthermore, gas holdup and liquid velocity in downcomer section did not show any significant variations with change in the top to bottom clearance ratio. The riser gas holdup data was related to the superficial gas velocity and the top to bottom clearance ratio data. Also, the downcomer gas holdup was related to superficial gas velocity and distance from airlift section.Secondly, viability and respirometric activity of activated sludge under different activated sludge conditions (batch, fed-batch) at high cell density as the model of membrane bioreactors were investigated. The results showed the same downward trend for both these parameters (viability and respirometric activity) which was due to quantitative and qualitative changes in the microbial culture in the activated sludge. Based on different fed of substrate for each experimental run (batch, fed-batch), operational variables showed significant influence in viability and activity of activated sludge. Also, the effect of changing physicochemical condition.on viability and respirometric activity was investigated. The results showed that respirometric activity was affected more strongly by temperature than viability.Thirdly, biological performance of AOXMBR was carried out.Finally, base on data obtained in the last experiment, in this part the capacitance sensor used as the on-line monitoring of viability of activated sludge in AOXMBR. Results showed that viability and activity were increased with organic loading rate (OLR) increasing until 5 kg COD m-3 d-1. This variation was in accordance with increasing of MLSS, MLVSS and OUR. The results also showed that the viability of biomass decreased when reducing the organic loading rate from 5 to 4 kg COD m-3 d-1. Also, protein concentration in system changed inversely with activated sludge viability.The possible reasons are discussed for future improvements online instrument for measuring viability and activity of activated sludge in biological wastewater. Summary of the principal results and novelty of this thesis obtained in this study: The porposed system would reward improved efficiency across the oxidation ditch, airlift and membrane bioreactor. The AXOMBR is a suitable system for operating at high organic laoding rate. However, the suddenly reduction of OLR affects on viability of activated sludge. The specific characterization of the system is capable of working at three different zone: aerobic, anoxic and anaerobic zone. Also, the time of operating at each zone can be changed with superficial gas velocity top to bottom clearance

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Piouceau, Julien. "Étude de la croissance de bambou cespiteux en peuplement mutlispécifique pour le traitement des eaux résiduaires." Thesis, La Réunion, 2013. http://www.theses.fr/2013LARE0004.

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Ce travail a pour objectif l'adaptation en climat tropical d'une technique de phytoépuration utilisant le bambou pour le traitement des eaux usées, déjà développée en climat tempéré. L'étude porte sur la détermination de valeurs de référence pour plusieurs espèces de bambou tropicales (i) des capacités d'absorption d'eau, (ii) de production de biomasse aérienne, et (iii) d'absorption des nutriments. La démarche expérimentale a consisté, dans un premier temps, à déterminer la réponse morphologique de sept espèces de bambous, suite à l'apport excessif de nutriments, comme cela peut se produire lors de l'apport d'eaux usées. Dans un deuxième temps, les capacités d'évapotranspiration de cinq espèces de bambous ont été étudiées en cuves lysimètriques. Enfin, la production de biomasse, ainsi que les prélèvements en azote, phosphore et carbone d'un peuplement multispécifique ont été étudiés en réponse à l'apport de lisier, en conditions réelles d'une station pilote. Ces études ont montré que des apports excessifs en nutriments améliorent la croissance du bambou sans causer de stress détectable. Ils améliorent également la capacité photosynthétique des bambous, ainsi que la production de biomasse, qui est augmentée d'un facteur 2 à 6 selon les espèces, par rapport au traitement témoin. La production de biomasse importante, de l'ordre de 20,7 à 80 tonnes de matière sèche produite par hectare et par an, confère aux espèces étudiées des capacités d'extraction élevées, avec des exportations de 400 à 1600 kg.ha-1 en azote, 30 à 130 kg.ha-1 de phosphore et 18 à 67 t.ha-1 de carbone piégé dans la biomasse en deux ans. Les taux d'évapotranspiration des bambous sont plus élevés que ceux de cultures classiques, avec des valeurs moyennes annuelles comprises entre 4 et 7mm/j et des coefficients culturaux moyens de 2,1 à 3,8 selon les espèces. Cette étude a permis d'identifier plusieurs espèces de bambous intéressantes pour le traitement des eaux usées en climat tropical, notamment les espèces Bambusa oldhamii, Bambusa vulgaris et Gigantochloa wrayii. Dans une optique de phytoépuration ces résultats sont d'autant plus encourageants qu'ils ont été obtenus avec des plants de bambou n'ayant pas encore atteints leur pleine maturité
The aim of this work was to adapt under tropical climate, a wastewater treatment phytotechnology which uses bamboo species, already developed under temperate climate. The objectives of the study were to establish reference values on the water and nutrient uptakes, and on above-ground biomass yields, for different tropical bamboo species. The experimental approach relied first in the quantification of the morphological response of seven bamboo species under high nutrient loads, up to 13.2 t.ha-1.yr-1 of NPK, as it occurs in wastewater treatment system. Second time, the evapotranspiration rates and crop coefficients of five bamboo species were determined using a lysimeter experiment. Finally, the biomass yield and the nitrogen, phosphorus and carbon uptakes were studied for a multi-specific bamboo plantation in response to pig slurry application, at field scale. The results have shown that the high nutrient load (13.2 t.ha-1.yr-1 of NPK) did not cause any detectable stress on the bamboo growth. On the contrary, the photosynthetic activity was improved and the growth rate was increased by 2 to 6 times compared with the control treatment. Depending on bamboo species, the annual biomass yield ranges from 20,7 to 80 t.ha-1.yr-1, and the nutrients storage into the biomass was 400 to 1600 kg.ha-1 for nitrogen, 30 to 130 kg.ha-1 for phosphorus and 18 to 67 t.ha-1 for carbon, in two years of experiment. The yearly average evapotranspiration rates were higher than for typical crops and range from 4 to 7mm.day-1, with average crop coefficients between 2.1 to 3.8, depending on species. Due to their high biomass yield, high nutrient uptakes and high evapotranspiration rates, some bamboo species, i.e. Bambusa oldhamii, Bambusa vulgaris and Gigantochloa wrayii appear as good candidates for wastewater treatment under tropical climate. These results are even more promising since they were obtained for non mature bamboo plants

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Vanneste-Ibarcq, Clément. "Study of biomass powders in the context of thermal recovery processes." Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2018. http://www.theses.fr/2018EMAC0019/document.

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Certains procédés de production d’énergie nécessitent l’utilisation de poudres de biomasse, par exemple la gazéification en réacteur à flux entraîné (RFE). Cependant, les poudres de biomasse ont une mauvaise coulabilité. L’objectif de cette thèse est d’étudier leurs propriétés d’écoulement dans le contexte de la gazéification en RFE, à l’échelle du laboratoire et à l’échelle pilote. A l’échelle du laboratoire, des mesures en tambour rotatif, des tests de cisaillement et des mesures de densité ont été effectués. D’une part, une corrélation est mise en évidence entre la cohésion (issue des tests de cisaillement), la densité et l’angle d’avalanche (tiré des mesures en tambour). Ainsi, un paramètre difficile à obtenir comme la cohésion peut l’être à partir de mesures simples. D’autre part, l’influence de l’humidité sur la coulabilité des poudres de biomasse a été évaluée. L’humidité n’a pas d’effet significatif sous 15 % (en masse, base humide), car l’eau est adsorbée dans la structure de la biomasse ; les particules gonflent et ne sont pas liées par des ponts liquides. Un procédé de granulation humide est proposé. Un liant issu de déchets de biomasse est ajouté à la poudre pour former des granulés d’environ 1 mm. Leur forme sphérique diminue l’entrelacement des particules et leur faible polydispersité diminue le nombre de points de contact. Une amélioration de l’écoulement est observée à l’échelle labo. Une étude énergétique montre que la consommation énergétique du procédé peut descendre jusqu’à 12% du pouvoir calorifique inférieur, ce qui suggère une potentielle rentabilité économique du procédé. Enfin, la caractérisation à l’échelle supérieure est effectuée dans un pilote reproduisant l’injection en RFE. Les résultats montrent le rôle essentiel de la sphéricité et d’une faible polydispersité des particules. L’effet positif de la torréfaction et de la granulation sur la coulabilité est mis en évidence
Some power generation processes require the biomass to be finely ground, such as biomass gasification in entrained flow reactors. However, fine biomass powders are cohesive and present flow issues. This thesis aims to study the biomass powder flowability in the context of the entrained flow gasification process. Biomass powders are characterized both at laboratory scale and pilot scale. Characterization at lab scale consisted of rotating drum measurements, shear tests and density measurements. First, a correlation is found between the cohesion (derived from shear tests), the powder density and the avalanche angle (derived from the rotating drum measurements). Thus, parameters difficult to get such as the cohesion can be obtained with easy to perform measurements. Then, the influence of moisture content on wood powder flowability has been assessed. No significant effect of the water content is found below 15 wt% (wet basis). Below 15%, as water is adsorbed in the biomass structure, the particles swell without being linked by liquid bridges. A wet granulation method is proposed. Biomass waste binders are added to the powder to form granules around 1 mm. The spherical shape lowers the interlocking phenomenon. The low size dispersity of the grains decreases the number of contact points between particles. An improvement of the flowability at lab scale is observed. An energetic study of the granulation process is proposed, showing the energy consumption can be as low as 12% of the biomass Lowest Heating Value. Thus, the process is potentially economically profitable. Finally, characterization at pilot scale is performed with a device mimicking the injection in an entrained flow reactor. The results show the essential roles in the injection step of both the spherical shape and the narrow size distribution of the particles. The positive effect of torrefaction and granulation on the flowability is highlighted

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Grave, Gwendoline. "Synthèse catalytique directe d'éthers à partir de glycérol et d'alcools pour des applications lubrifiantes." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2017. http://www.theses.fr/2017ENCM0001.

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Le défi de cette thèse est d’utiliser le glycérol, co-produit de la production de biodiesel, pour synthétiser des molécules ayant des propriétés lubrifiantes en restant dans le cadre d’une chimie verte. Cette étude porte sur l’éthérification en deux étapes du glycérol par un alcool par catalyse acide. Les objectifs principaux de ce projet sont donc la synthèse et la purification de mono-, di- et tri-éthers de glycérol (MEG, DEG, TEG), ainsi que l’étude des relations entre leurs structures et leurs propriétés pour des applications lubrifiantes. Les propriétés tribologiques de ces molécules comme modificateurs de frottements pour les lubrifiants ont été évaluées au Centre de Recherches de Solaize (CReS).La formation d’éthers de glycérol par des alcools a déjà été largement étudiée dans la littérature. Pour contourner le problème d’immiscibilité entre le glycérol et les alcools gras, la première éthérification a été réalisée avec un alcool court (6 carbones) et la seconde avec un alcool long (>7 carbones), les mono-éthers de glycérol étant miscibles avec les alcools gras. Ainsi la formation de MEG et DEG avec plus de vingt carbones est rendue possible. Dans ce travail, les paramètres de réaction (ratio entre les réactifs, nature et quantité de catalyseurs, purification) ont été optimisés pour deux réactions modèles. La première réaction est l’éthérification entre le glycérol et le 1-hexanol, et la seconde, l’éthérification entre le mono-hexyl de glycérol obtenu et le 1-hexanol. Une des difficultés principales de ces réactions est la séparation et la purification des différents éthers obtenus, à cause notamment de leurs structures très proches, ainsi que de la présence de sous-produits tels que des oligomères de glycérol. L’optimisation du procédé de purification des produits a donc représenté un des volets importants de cette thèse. Les meilleures conditions de purification déterminées ont permis d’extraire 80% du mono-hexyl éther de glycérol synthétisé du milieu réactionnel brut. L’optimisation des conditions opératoires et de la purification ont permis d’étendre l’éthérification du glycérol à plusieurs autres alcools de structures différentes. Par cette méthode, dix-huit échantillons de mono et/ou di-éthers de glycérol différents ont été obtenus. Chacun de ces échantillons a été testé au Centre de Recherches TOTAL de Solaize en tant qu'additifs modificateurs de frottements pour les lubrifiants. Ces tests ont permis d’établir des corrélations entre la structure chimique des molécules et leurs propriétés tribologiques
The challenge of this PhD is to use glycerol, by-product of biodiesel production, to generate molecules of interest via green processes. This study is focused on the two step etherification of glycerol with alcohols over acid catalysts. The main prospect of this project is the study of the relationships between the structures of the mono-, di- and tri-ethers (MEG, DEG and TEG) and their properties for lubricant applications. The tribological properties of these products as friction modifiers have been evaluated at the TOTAL Research Center in Solaize. The formation of ethers of glycerol with alcohols has already been widely studied in the literature. To overpass the immiscibility between glycerol and fatty alcohols the first etherification has be performed with a short alcohol as a reactant, while the second has been performed with a fatty alcohol, the previously obtained mono-ethers being miscible with fatty alcohols. Thus, the formation of di- and tri-ethers of glycerol with more than twenty carbons becomes possible. In this work, the reaction parameters (ratio between reactants, the nature and amount of catalyst, and the purification) were optimized for two model reactions. The first reaction was the etherification between glycerol and 1-hexanol and the second was the etherification of the previously obtained MEG with 1-hexanol. One of the main challenges of these reactions is the separation and purification of the ethers, because of their very structures, and the presence of by-products such as oligomers of glycerol or ethers. The optimization of the purification process of the ethers has then been one of the major challenges of this work. The best purification conditions have allowed the extraction of 80% of the synthesized mono-hexyl ether from the reaction medium.The optimization of operating conditions of the various reactions used, as well as the purification of the obtained ethers, allowed the extension of the scope of reaction to several alcohols of different structures. Consequently, eighteen different samples of mono- and/or di-ethers of glycerol have been obtained and tested at the TOTAL Research Center in Solaize as friction modifiers in lubricants. These tests have led to the establishment of relationships between the chemical structure of the molecules and their tribological properties

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Dietzsch, Anke. "Nutzung kontaminierter Böden." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-70887.

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Auf arsen- und schwermetallbelasteten Böden im Raum Freiberg/Sachsen erfolgten Kalkdüngungsversuche und der Anbau von Weiden und Pappeln zur energetischen Verwertung. Nach der Kalkung auf Acker- und Grünlandflächen nahm der pflanzenverfügbare Anteil an Cadmium und Blei im Oberboden ab, nicht jedoch bei Arsen. Obwohl der Boden des Grünlandes hoch mit Blei und Arsen belastet war, wurde der Futtermittelgrenzwert nur vereinzelt bei Arsen und teilweise bei Cadmium überschritten. Bei Cadmium wurden erst mit zunehmendem pH-Wert und damit sinkendem pflanzenverfügbaren Anteil an Cadmium die Grenzwerte eingehalten. Die Kurzumtriebsplantage mit Pappeln und Weiden erreichte sehr gute Erträge. Sie lagen nach drei Anbaujahren bei 6,3 t TM/ha*a und nach weiteren zwei Jahren bei 16 t TM/ha*a. Weiden nahmen im Vergleich zu Pappeln die dreifache Menge an Cadmium und Zink auf. Die Einlagerung erfolgt insbesondere in den Blättern. Die belasteten Brennstoffe wurden in Feuerungsanlagen energetisch verwertet, die Aschen analysiert. Die Vergasung von Miscanthuspellets in einer zirkulierenden Wirbelschicht erfolgte problemlos.

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Hassan, El Sayed Rabie El Sayed. "Use of Ionic Liquids for the Treatment of Biomass Materials and Biofuel Production." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0043/document.

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Le remplacement des solvants organiques classiques par une nouvelle génération de solvants moins toxiques et moins polluants est un défi majeur pour l'industrie chimique. Les liquides ioniques (LIs) ont été largement identifiés comme substituts intéressants aux solvants traditionnels. Le but de ce travail est d'étudier la solubilité des sucres ou des constituants issus de la biomasse dans les liquides ioniques afin de pallier au manque de données expérimentales sur les équilibres de phases de systèmes {sucres + LIs} ou {biomasse + LIs}. Les données de solubilité ont été corrélées avec succès en utilisant les modèles thermodynamiques NRTL et UNIQUAC. Cette étude démontre que la méthode de l'antisolvant est une bonne technique pour l'extraction des sucres des LIs. Par conséquent, les liquides ioniques peuvent être facilement recyclés pour être réutilisés. Les natures fondamentales des interactions entre les sucres et les liquides ioniques ont été définies en utilisant le calcul ab initio. Les résultats obtenus par simulation sont en accord avec les données expérimentales et indiquent que les liquides ioniques interagissent avec les sucres par liaisons hydrogène. La seconde partie de ce travail met en évidence que le prétraitement du miscanthus avec les liquides ioniques permet d'obtenir une bonne production d'éthanol (jusqu'à 150 g d'éthanol par kg de miscanthus). Les résultats montrent que les liquides ioniques sont des solvants performants dans le domaine de la conversion des matières premières issues de la biomasse en biocarburant. Ainsi, l'application à l'échelle industrielle de ces procédés d'extraction de la cellulose pourrait être d'un grand intérêt
The replacement of conventional organic solvents by a new generation of solvents less toxic, less flammable and less polluting is a major challenge for the chemical industry. Ionic liquids have been widely promoted as interesting substitutes for traditional solvents. The purpose of this work is to study the solubility of carbohydrates or biomass based materials in ionic liquids in order to overcome the lack of experimental data on phase equilibria of {biomass or carbohydrate-ILs} mixtures. Solubility data were successfully correlated using NRTL and UNIQUAC thermodynamic models. It was found that the antisolvent method is a good technique for the extraction of carbohydrates from ILs. Ionic liquids could be then recycled successfully for reuse. The fundamental natures of the interaction between carbohydrates and ionic liquids were investigated using ab initio calculations. The theoretical results are in good agreement with experimental data. It was concluded that ionic liquids mainly interact with carbohydrates via hydrogen bonding formation. This confirms that the process of dissolution and regeneration of cellulose in ionic liquids is accompanied only with a physical change. The preatreatment of miscanthus with ionic liquids resulted in the regeneration of amorphous, porous cellulose almost free of lignin, which is suitable for enzymatic hydrolysis and fermentation processes. A successful ethanol production was obtained with an overall ethanol yield reached up to 150 g ethanol kg-1 miscanthus. This indicates the high performance of ionic liquids in converting biomass feedstocks into biofuel. Indeed, applying the cellulose extraction processes on the industrial scale could be of great interest

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Dang, Thi Thu Huong, and Huu Thu Do. "Biomass and carbon stocks of the natural forests at Me Linh biodiversity station, Vinh Phuc province, Vietnam." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-190821.

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Biomass and carbon stock of the natural forests in Vietnam are still not clear due to limitation of knowledge and financial. In this paper, the results of estimating biomass and carbon stocks of the natural forests at Me Linh Biodiversity Station are shown. There are two forest types in this study: the forest vegetation restored after shifting cultivation (vegetation type I) and the forest vegetation restored after clear cutting exploitation (vegetation type II). As the results, the estimated biomass of the forest vegetation restored after shifting cultivation is 86.80 ton.ha-1 and the estimated biomass of the forest vegetation restored after clear cutting exploitation is higher, about 131.59 ton.ha-1. The carbon stock in plants was about 43.40 ton.ha-1 of vegetation type I and 65.79 ton.ha-1 of vegetation type II. The carbon storage in soil of vegetation type I is 79.01 ton.ha-1 and vegetation type II is 99.65 ton.ha-1. Hence, the total of carbon stock in forest vegetation I and II are accounted by 122.41ton.ha-1 and 165.44 ton.ha-1, respectively. In general, it can be pointed out that the naturally recovering secondary forest at Me Linh Station is the secondary young forest with the low economic value due to shortly restored process (about 10-20 years), the flora is not rich and abundant, and there are only commonly pioneer and light demanding tree species
Sinh khối và trữ lượng các bon của rừng tự nhiên ở Việt Nam vẫn ít được quan tâm của do hạn chế về kiến thức và tài chính. Trong bài báo này, chúng tôi đưa ra kết quả của việc ước lượng sinh khối và tổng hợp các bon của các thảm thực vật rừng thứ sinh phục hồi tự nhiên tại Trạm Đa dạng Sinh học Mê Linh, tỉnh Vĩnh Phúc- Việt Nam, nơi có loại hình thảm thực vật chính, đó là thảm thực vật phục hồi sau nương rẫy (kiểu thảm thục vật I) và thảm thực vật phục hồi sau khai thác kiệt (kiểu thảm thực vật II) nhằm mục đích đánh giá tiềm năng của rừng thứ sinh tại khu vực nghiên cứu. Sinh khối của thảm thực vật phục hồi sau nương rẫy là 86,80 tấn/ha. Sinh khối của thảm thực vật phục hồi sau khai thác cao hơn, đạt 131.59 tấn/ha. Lượng các bon hấp thu trong đất của thảm thực vật I là 79,01 tấn/ha và thảm thực vật II là 99,65 tấn/ha. Như vậy, tổng lượng các bon được hấp thu trong mỗi loại hình thảm thực vật trên là: 122,41 tấn/ha (thảm thực vật I) và 165,14 tấn/ha. Nhìn chung, rừng thứ sinh phục hồi tự nhiên tại Trạm Đa dạng Mê Linh chủ yếu là rừng non thứ sinh, ít có giá trị kinh tế do quá trình phục hồi diễn ra ngắn (khoảng 10-20 năm) nên thành phần thực vật nghèo nàn, không phong phú, thành phần chính chủ yếu là các cây gỗ tiên phong, ưa sáng

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Fahrudin, Kulić. "Multikriterijska optimizacija instrumenata energetske politike korištenja biomase." Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2016. http://www.cris.uns.ac.rs/record.jsf?recordId=101285&source=NDLTD&language=en.

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U ovom radu je prezentirana metodologija razvoja modela optimizacijepodsticaja proizvodnje električne i toplotne energije ukogenerativnim postrojenjima koja koriste drvnu biomasu kao gorivo.Model optimizacije je razvijen koristeći matematičku metodulinearnog programiranja u kome je maksimizirana ukupna ekonomskakorist za raspoloživi iznos sredstava za podsticaje. Modeloptimizacije je primijenjen na kogenerativna postrojenja u drvo-prerađivačkoj industriji u Bosni i Hercegovini i pokazano da seprimjenom modela optimizacije, kroz iterativni proces, mogu odreditioptimalne vrijednosti podsticaja za proizvedenu električnu itoplotnu energiju koji rezultuju u maksimalnoj ukupnoj ekonomskojkoristi za društvo u cjelini.
This thesis presents a methodology for the development of a mathematicalmodel for optimization of the level of subsidies for generating electricity andheat in co-generating plants that use woody biomass as fuel. The optimizationmodel is developed using the mathematical method of linear programming tomaximize the total economic benefits for a defined amount of available fundsfor subsidies. This model is applied to co-generating plants in the woodprocessingindustry in Bosnia and Herzegovina and shows that the applicationof this optimization model can, through an iterative process, determine theoptimal levels of incentives for electricity and heat that result in the maximumeconomic benefits for the society as a whole.

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Kučera, Dan. "Využití lignocelulózových materiálů k biotechnologické produkci polyhydroxyalkanoátů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2015. http://www.nusl.cz/ntk/nusl-217161.

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Tato diplomová práce se zabývala možnostmi utilizace lignocelulosového materiálu jako obnovitelného zdroje k produkci polyhydroxyalkanoátů (PHA) biotechnologickými metodami. Teoretická část práce se zaměřuje na charakterizaci rostlinné odpadní biomasy, její enzymatickou sacharifikaci a možnosti produkce a izolace hydrolytických enzymů. Dále se pak literární rešerše zabývá bakteriální produkcí PHA a možností využití lignocelulosové biomasy pro jejich produkci. V rámci experimentální části byly vybrané odpadní substráty hydrolyzovány chemickou a enzymatickou cestou. Jako odpadní substráty byly použity výlisky z jablek, hroznového vína a řepky olejné a kávová sedlina. Získané hydrolyzáty byly použity k produkci PHA bakteriálním kmenem Burkholderia cepacia. Nejslibnějším substrátem se jevily výlisky z jablek. Ukázalo se, že vybraný bakteriální kmen je schopen utilizovat odpadní substráty i bez předchozí úpravy. Supernatant po skončení kultivace jevil následující aktivity: proteasovou, lipasovou (0.47 nmol/(mL•min)), celulasovou pro CMC (6.05 nmol/(mL•min)) a filtrační papír (4.63 nmol/(mL•min)) a xylanasovou (1.71 nmol/(mL•min)). Tyto enzymy mohou představovat zajímavý vedlejší produkt výroby PHA z odpadních zemědělských materiálů. V rámci této práce byl také posouzen vliv délky kultivace a způsob hydrolýzy na výslednou produkci PHA a enzymatickou aktivitu průmyslově zajímavých enzymů.

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Ferdan, Tomáš. "Čištění spalin v jednotkách pro termické zpracování biomasy." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229287.

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The master’s thesis deals with thermal treatment of biomass and with reduction of emission, which originate during this process. First part speaks commonly about biomass incineration and about technologies for emission reduction, especially cyclones. Practical part of this paper involves description of multicyclone evaluation by different authors and the comparison on of the evaluation on a case study of concrete multicyclone.

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Budai, Karel. "Zplyňování biomasy v atmosféře se zvýšeným obsahem oxidu uhličitého." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-400507.

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This diploma thesis deals with the use of CO2 in gasification of biomass. The theoretical part is focus on description of gasification process and gasification reactors. The next part descripes the influence of the gasifitation medium composition on the properties of the generated gas. The experimental part is devoted to gasification of biomass on a fluidized bed generator, where the effect of CO2 concetration in the gasification medium on the properties of the generated gas is investigated. In the final part is the evaluation of the results.

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Baláš, Marek. "Čištění energoplynu kovovými katalyzátory." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-233920.

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Gasification of biomass is a one of the several technologies for energy production from biomass. Biomass is a promising renewable source of energy and is in a centre of attention of energy industry not only in the Czech Republic, but also in the EU and in the world. Gasification is a thermo chemical transformation of fuel with access of understoicheiometric amount of oxidizer which produces gas of low heating value. Its main combustible components are hydrogen, carbon dioxide and methane. Produced gas may be further used in power and heating plants. Besides combustible and neutral components, gas also contains pollutants such as sulphur compounds, chlorine compounds, ash and tar. It is tar which is considered to be the underbelly of gasification as it causes, along with ash, fouling in transport tracks and terminal equipment, and blocks direct application of gas. This dissertation thesis presents design of filter for elimination of tar from the gas generated in fluid gasification equipment. This work is closely related to current research at Energy Institute at Faculty of Mechanical Engineering at Brno University of Technology. First part deals with theoretical background of this issue. Biomass properties are mentioned in relation to gasification. Types of gasification equipment are described and principle of gasification including chemical reactions is given in detail. Special part is dedicated to pollutants in the gas, especially to production of tar and its properties, which is important for consequent work. Main focus is on possibilities of catalytic cleaning of gas from tar. Principle of tar decomposition is described and types and properties of catalysts are given. Part of the thesis tackles the issue of real operations and loss of efficiency of catalyst due to sulphur compounds, sintering and carbon fouling. Based on experience and analysis in the first part of the thesis, concept of elimination of tar from gas was laid out. In addition to that, method for measurement at Biofluid 100 experimental unit was outlined and filter for testing of industrial catalysts using metal was designed. Series of experiments were further conducted in order to find out efficiency of three opted catalysts for tar decomposition. Results of these experiments are described in detail and assessed in the conclusion of this thesis which also contains outline for economic assessment of method of gas cleaning using catalysts.

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Heid, Laura. "Variabilité intra-annuelle de l’efficacité de production de biomasse aérienne (aBPE) d’une forêt : comparaison avec une prairie soumise aux mêmes conditions climatiques." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0318/document.

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L’étude du cycle du carbone (C) dans les écosystèmes terrestres est fondamentale afin de comprendre leur rôle dans le cycle du carbone ainsi que les répercussions du changement climatique sur ces écosystèmes. L'objectif général de la thèse qui est de faire un suivi intra-annuel de l’allocation du C au sein de différents écosystème terrestre (forêt et prairie), se place dans ce contexte. Dans un premier temps les efficiences de production de biomasse aérienne (aBPE, rapport entre les quantités de carbone stockées dans la biomasse aérienne et absorbées) sont calculées pour des intervalles de temps réduits, du mois à la semaine selon l’écosystème (forêt et prairie). Dans un second temps, une estimation plus précise de l'allocation du carbone en forêt a été effectuée, en suivant la formation de certains composés structuraux (hémicelluloses et cellulose+lignine). Un possible lien entre la variation de cette allocation selon les conditions climatiques a été étudiée. Les efficiences correspondantes ont également été calculées mensuellement pour avoir une idée plus précise du stockage durable du C dans cet écosystème. Une comparaison avec la prairie a été réalisée en termes d’aBPE afin d'analyser les capacités respectives des 2 écosystèmes à s'adapter aux changements climatiques et à jouer un rôle dans la mitigation des gaz à effet de serre. Dans le cadre de l'Observatoire Pérenne de l'Environnement, deux écosystèmes voisins situés en Meuse (55) ont été instrumentés dans le but de mesurer en continu les échanges de CO2 à l’interface couvert‐atmosphère, ainsi que les conditions micrométéorologiques dans lesquelles ces échanges se produisent. De plus, un suivi régulier du développement des écosystèmes a également été réalisé
The study of the carbon (C) cycle is important in terrestrial ecosystems (forest, grassland) in order to understand their behavior, their role in the C cycle and also the impact of climate change on them. The general study of this thesis which is to monitor the intra-annual allocation of C into different terrestrial ecosystem (forest and grassland), lays within this context. Firstly we calculated aboveground biomass production efficiencies (aBPE, ratio between the quantity of C stored into the aboveground biomass and absorbed) intra-annually, weekly or monthly depending on the ecosystem (grassland and forest respectively). Secondly a more precise assessment of the C allocation in forest was made by analyzing the formation of structural C compounds (hemicelluloses and cellulose + lignins). A possible link between the variability of these allocations and climate was studied. The corresponding efficiencies were then calculated monthly in order to have a better idea of the sustainable C storage in this ecosystem. A comparison with a grassland in term of aBPE was then realized in order to analyze the adaptation capacity of each ecosystem to climate change and to play a role in the mitigation of GHG. Two neighboring ecosystems located in Montiers-sur-Saulx and Osne-le-Val were equipped, as part of the Observatoire Pérenne de l’Environnement (OPE), to measure continuously the CO2 exchange between land cover and atmosphere and the micrometeorological conditions in which these exchanges happen. A regular monitoring of those ecosystems development (biomass, leaves area, senescence) was also made

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Hiblot, Hélène. "Etude cinétique du reformage thermique des produits issus de la gazéification de la biomasse." Thesis, Vandoeuvre-les-Nancy, INPL, 2010. http://www.theses.fr/2010INPL028N/document.

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Des applications avancées, telles que la production catalytique de combustibles liquides, demande un gaz de synthèse de haute pureté. La biomasse semble être une matière première prometteuse, mais le gaz doit être nettoyé de façon drastique pour atteindre les spécifications. Le reformage à haute température (> 1300 K) est une alternative crédible à la voie catalytique. La cinétique de reformage à haute température dans une atmosphère réductrice est mal connue. Si des mécanismes détaillés existent déjà pour la combustion d'hydrocarbures, les réactions sensibles sont différentes dans ce cas. Une étude expérimentale en réacteur piston et une modélisation du vapocraquage d'hydrocarbures ont été réalisées. L'influence cinétique des gaz présents dans le gaz de synthèse sur la conversion des hydrocarbures a été étudiée. Le comportement de mélanges complexes représentatifs des gaz à traiter a été étudié en fonction de la température. L’espèce la plus difficile à reformer est le méthane : une température supérieure à 1700 K est nécessaire. Un modèle dérivé de celui de la combustion des hydrocarbures légers a été élaboré. Les tendances expérimentales sont bien reproduites. Le reformage du carbone se fait principalement par réaction des radicaux OH avec les C₂ insaturés, précurseurs de suie. Les conditions nécessaires pour reformer le méthane à haute température sont également donc favorables à la formation de suies indésirables
Advanced applications, such as catalytic production of liquid fuels, request a high quality synthesis gas. Biomass may be a promising feedstock but the syngas needs to be drastically cleaned to reach the specifications. The high temperature homogeneous reforming (> 1300 K) seems a credible alternative to the catalytic way. The reforming kinetic at high temperatures in a reducing atmosphere has to be understood. If detailed mechanisms already exist for the combustion of hydrocarbons, sensitive reactions are different in this case. An experimental and modelling study of the steam cracking of small hydrocarbons have been performed. The experiments have been done in a plug flow reactor under atmospheric pressure. The kinetic influence of different gases of the syngas on the hydrocarbons conversion has been investigated. The behaviour of representative complex mixtures has been also studied as a function of the temperature. The most difficult species to reform is methane: temperature as high as 1700 K is necessary. A model derived from that for the combustion of light hydrocarbons was developed. The experimental trends are well reproduced. Carbon reforming appends mainly by reaction of OH radicals with unsaturated C₂ molecules, which are soot precursors. Process conditions necessary for high temperature methane reforming would then be favourable to undesirable soot formation

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Žmolík, Václav. "Energetická bilance bioteplárny." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228660.

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This thesis deals with a design of a biomass heating plant combinating a Rankin-Clausius cyklus and a CHP unit. The CHP unit fuel is a biogas and the boiler fuel is a wooden chip. The adapted CHP unit regenerates feed-water of the R-C cycles. This design is technicaly and economicalty compared with the Rankin-Clausius cycle without feed-water regeneration by the CHP unit.

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Feldwisch, Norbert. "Umweltgerechter Anbau von Energiepflanzen." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-80877.

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Für den Anbau von Biomasse-Dauerkulturen wie schnellwachsende Baumarten werden Anbauhinweise und -empfehlungen gegeben, die Aspekte des Boden-, Gewässer- und Naturschutzes berücksichtigen. Standorteignung, Wirkungen auf wildlebende Pflanzen- und Tierarten, entstehende Synergieeffekte, Einflüsse auf den Wasserhaushalt, Stoffeinträge in Gewässer sowie klimatische Wirkungen sind Teilaspekte, unter denen die Chancen und Risiken der energetischen Nutzung nachwachsender Rohstoffe im Rahmen eines mehrjährigen Verbundvorhabens in Sachsen untersucht wurden. Ergänzend wurde auch der Anbau einjähriger Energiepflanzen betrachtet.

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Magdechová, Andrea. "Stanovení organických sloučenin v dehtu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-216728.

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The diploma thesis deals with determination of organic compounds in the tar. It is focussed on polycyclic aromatic hydrocarbons, BTEX and n-alkanes. The tar samples were collected by Faculty of Mechanical Engineering BUT Brno during two days and under diferent conditions of biomass gasification. The samples were filtrated and refined using column chromatography on silicagel sorbent. Gas chromatography with mass detection was chosen to determine polycyclic aromatic hydrocarbons and gas chromatography with flame ionisation detection was chosen to determine BTEX and n-alkanes.

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Gelas, Colette. "Inversion de données PolSAR en bande P pour l'estimation de la biomasse forestière." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30282.

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La thèse s'inscrit dans le cadre des travaux préparatoires à la mission spatiale BIOMASS du programme Earth Explorer de l'ESA (Agence Spatiale Européenne), qui prévoit d'exploiter pour la première fois depuis l'espace un SAR en bande P (435 MHz), dans le but de cartographier la biomasse et la hauteur des forêts à l'échelle globale pour la période 2023-2028. L'utilisation de la bande P permet d'obtenir une sensibilité du signal inédite avec la biomasse, en lien avec ses capacités de pénétration même à travers des forêts tropicales denses. La mission BIOMASS se base sur l'utilisation conjointe de trois méthodes d'imagerie qui sont la Polarimétrie (PolSAR), l'Interférométrie (PolInSAR) et la Tomographie (TomoSAR). Ses objectifs sont de produire tous les 7 mois des cartes de biomasse et hauteur des forêts à la résolution de 4 ha, ainsi que des cartes des perturbations sévères à 0.5 ha. La thèse s'est organisée autour du développement d'une chaîne de calcul articulée en plusieurs modules permettant d'extraire des valeurs de biomasse à partir de données PolSAR en bande P dans la perspective de cartographier la biomasse forestière de manière robuste et automatique. Les deux modules principaux consistent à estimer un indicateur polarimétrique lié à la biomasse forestière puis à l'inverser en biomasse en appliquant une méthode bayésienne construite sur des grandeurs a priori issues d'un modèle électromagnétique prédictif (MIPERS-4D). Une étude a été consacrée à la comparaison de différents indicateurs PolSAR permettant l'inversion de la biomasse forestière sur les différents sites expérimentaux étudiés. Cette thèse aborde la possibilité de minimiser les effets de la topographie avec une utilisation conjointe des modèles numériques d'élévation (DEM) qui donnent une approximation des pentes sous forêts et des données PolSAR à partir desquelles il est possible d'extraire des informations sur les coefficients des matrices de covariances et sur les pentes azimutales sous forêt. Dans l'objectif d'améliorer les relations entre les coefficients de rétrodiffusion et la biomasse, la minimisation des effets de speckle a également été étudiée dans le cadre des scénarios d'acquisitions BIOMASS, supposant des adaptations des techniques de filtrage existantes pour des séries temporelles de données SLC polarimétriques. Ces travaux sur le développement d'un filtre multi-temporel et multi-canal adapté aux séries temporelles PolSAR ont été valorisés dans l'article "Multi-temporal speckle filtering of polarimetric P-band SAR data over dense tropical forests in French Guiana : application to the BIOMASS mission" (publié dans la revue Remote Sensing), dans lequel un nouvel indicateur permettant de quantifier les performances du filtrage a également été proposé, en lien avec la capacité inédite de ces données pour caractériser les pentes azimutales du terrain. Ces différents travaux ont permis de mettre au point une méthode d'inversion adaptable aux contraintes de généralisation spatiale et temporelle pour les futures acquisitions BIOMASS à l'échelle globale. La méthode développée repose sur la combinaison d'un indicateur issu des données PolSAR qui optimise la relation à la biomasse ainsi que d'une méthode bayésienne minimisant les effets de dispersion à partir de fonctions de vraisemblance issues du modèle MIPERS-4D. Les conditions d'observations peuvent ainsi être prises en compte au travers de la paramétrisation du modèle, et l'application de cette méthode aux données des campagnes aéroportées étudiées dans cette thèse a montré son intérêt pour éviter la propagation directe des effets temporels ou de structure en biomasse. La combinaison de ces différentes études a permis d'améliorer la méthode d'inversion tout au long de la thèse, en ouvrant également des perspectives de développement pour la consolider avec en particulier la généralisation aux indicateurs PolInSAR et TomoSAR, en vue d'une exploitation la plus complète des futures données BIOMASS
This thesis took place during the preparation phase of the BIOMASS ESA (European Space Agency) mission, which plans to exploit for the first time ever a P-band (435 MHz) spaceborne SAR, with the aim at mapping forest biomass and height worldwide for the period 2023-2028. The use of the P-band comes from its unique sensitivity to forest biomass, in relation to its ability to penetrate through dense media like tropical forests. The BIOMASS mission is based on the use of three imaging modes: Polarimetry (PolSAR), Interferometry (PolInSAR) and Tomography (TomoSAR), and aims at delivering forest biomass and height maps every 7 months at a resolution of 4 ha, as well as maps of severe disturbances at 0.5 ha. The thesis has been organised around the development of a processing chain made of several modules in order to map forest biomass from P-band PolSAR images, and for a wide range of forest types and observation conditions. The two main modules consist in the development of a PolSAR indicator related to forest biomass and in a Bayesian method built on likelihood functions derived from a predictive electromagnetic model (MIPERS-4D). A first study focused on the comparison between various PolSAR based indicators adapted to forest biomass estimation on several test sites. In particular, this thesis emphasises the possibility of minimising the effects of topography with the joint use of digital elevation models (DEM) which give an approximation of terrain slopes and with the fully polarimetric covariance matrix from which it is also possible to extract topographic information like the azimuthal component of terrain slopes. In order to improve the link between backscatter coefficients and biomass, the minimisation of speckle effects has also been studied in the specific framework of BIOMASS acquisitions plan, meaning the adaptation of state-of-the-art filtering techniques for polarimetric SLC time series data. This work results in the development of a multi-channel filter adapted to PolSAR time series, which has been demonstrated on the TropiSAR data acquired at the Paracou test site, and described in the paper "Multi-temporal speckle filtering of polarimetric P-band SAR data over dense tropical forests in French Guiana: application to the BIOMASS mission", published in the journal Remote Sensing, in which a new indicator to quantify filtering performances has been also highlighted, in connection with the capacity of P-band PolSAR data to characterise the azimuthal slopes. These works contribute to develop an inversion method accounting for the challenging constraints of spatial and temporal generalisations for the future BIOMASS acquisitions at global scale. The developed method proposes the combination of the so-called t0 indicator derived from PolSAR data in order to optimise the relationship with forest biomass, with a Bayesian method minimising the dispersion effects thanks to likelihood functions derived from the MIPERS-4D model. The observation conditions related to the temporal or spatial variability can be thereby accounted for, and application of the method to the P-band airborne SAR data acquired during the BIOMASS mission preparation phases shows its great interest to avoid the direct propagation of dispersive factors into biomass. These contributions enabled to adapt and improve the processing chain, and paved to way to further prospects of new insights such as the method generalisation with PolInSAR and TomoSAR indicators, in order to achieve a more thorough exploitation of the upcoming BIOMASS data

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Arnaubec, Aurelien. "Analyse de la précision d'estimation de paramètres de la biomasse végétale à l'aide de techniques PolInSAR." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4320.

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Les techniques polarimétriques et interférométriques SAR (PolInSAR) en bande P (250Mhz - 500Mhz), offrent une solution à échelle mondiale pour l'étude des paramètres de la biomasse végétale. L'objectif de ce travail de doctorat est de proposer une analyse de la précision d'estimation que l'on peut espérer obtenir à l'aide de ces techniques pour certains paramètres tels que la hauteur de la végétation et du sol, en s'appuyant sur une des modélisation de la végétation les plus utilisées (modèle RVoG). Nous avons tout d'abord déterminé la Borne de Cramér-Rao (BCR) qui permet de fournir une borne inférieure à la variance d'estimation lorsque cette dernière est sans biais. Cette étude montre qu'il peut exister une grande diversité de situations, avec dans les cas favorables un écart type d'estimation de l'ordre du mètre pour une taille d'échantillon de 100 pixels. Il a pu ainsi être montré que la technique d'estimation la plus utilisée conduit à des variances proches de la BCR dans un grand nombre de situations. Cette étude a également permis d'analyser les performances quand on réduit l'information polarimétrique (Polarimétrie Compacte). Nous avons ensuite analysé l'influence de quelques écarts au modèle RvoG (fluctuations de la hauteur du sol et de la végétation, et décorrélation temporelle). La décorrélation temporelle semble être la perturbation la plus critique car elle peut fortement biaiser l'estimation. Finalement nous avons illustré, sur des forêts tropicales et tempérées, certains de ces résultats théoriques à l'aide de données acquises par les systèmes radar RAMSES et SETHI de l'ONERA en bande P
Polarimetric and Interferometric SAR techniques (PolInSAR) offer a global solution for vegetal biomass parameters monitoring. In the scope of this thesis, we propose to analyze the estimation precision that can be achieved with those techniques for some parameters such as ground and vegetation height, based on one of the most widely used PolInSAR vegetation model (RVoG model). We have first determined the Cramer-Rao bound (CRB), which gives a lower bound on the estimation variance, for unbiased estimation. This study shows a high diversity of situations, with in the best cases a precision of around 1 meter for a sample size of 100 pixels. It was shown that the most commonly used estimation method leads to estimation variances close to the CRB in a lot of situations. This study also allowed us to analyze the performance loss when polarimetric information is reduced (Compact Polarimetry). Then, we analyzed the influence of some deviations from the RVoG model (ground and vegetation height fluctuations, and also temporal decorrelation). Temporal decorrelation seems to be the most concerning issue as it can lead to high estimation bias. These theoritical results have been illustrated on tropical and tempered forests using P band data acquired by RAMSES and SETHI, the ONERA radar systems

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46

Zhang, Yu. "Valorisation catalytique de produits oxygénés issue des biorafinneries de lingo-cellulose." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1013.

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Cette thèse porte sur l'hydrogénation en phase gazeuse du furfural sur des oxydes de fer et de magnésium. De nombreux catalyseurs avec différents ratio molaires en fer et magnésium ont été préparés par des méthodes de co-précipitation ou d'imprégnation. Ils ont été ensuite testés lors de la réduction du furfural (FU) en utilisant du méthanol comme donneur d'hydrogène. L'alcool furfurylique (FAL) et le 2-methyl furfural (MFU) étaient les principaux produits obtenus démontrant alors que les systèmes Mg/Fe/O peuvent favoriser les réactions d'hydrogénation séquentielles et d'hydrogénolyse. Les catalyseurs imprégnés se sont révélés plus actif et sélectif vis-à-vis des MFU que ceux préparés par co-précipitation. Les données rapportées ont montré que la distribution du produit était fortement influencée par la teneur en fer et par l'acide résultant, ainsi que les propriétés d'oxydoréduction du matériau. En effet, l'introduction de fer à la surface d'oxyde basique a conduit à l'addition d'acidité de Lewis et de potentiel d'oxydoréduction dans le système, améliorant significativement la conversion de FU et la production de MFU. L'activation des différentes espèces à la surface du catalyseur a été étudié in-situ par DRIFTS et FTIR. Les résultats révèlent que la basicité du MgO favorise l'activation du méthanol et que le potentiel d'oxydoréduction du FeOx pourrait être responsable de l'hydrogénolyse de l'alcool furfurylique
This PhD project is focused on the gas phase hydrogenation of furfural over iron and magnesium oxides. Numerous catalysts with different iron and magnesium molar ratios, were prepared by co-precipitation or impregnation methods and were tested for the reduction of furfural (FU) using methanol as hydrogen donor. Furfuryl alcohol (FAL) and 2-methyl furfural (MFU) were the main products obtained, demonstrating that Mg/Fe/O systems can promote sequential hydrogenation and hydrogenolysis reactions. Impregnated catalysts demonstrated to be more active and selective towards MFU than co-precipitated ones. Reported data demonstrated that product distribution was strongly influenced by the iron content and from the resulting acid and redox properties of the material. As a matter of fact, the introduction of iron on the surface of the basic oxide led to the addition of Lewis acidity and redox capacity in the system, significantly enhancing FU conversion and MFU production. The activation of different species on the catalyst surface has been studied by in situ DRIFTS and FTIR. The results reveal that the MgO basicity favors methanol activation and FeOx redox capacity might be the responsible of furfuryl alcohol hydrogenolysis

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Gavilà, Terrades Llorenç. "Different biomass conversion strategies for valuable chemical production." Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/457135.

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Com a alternativa a la producció química a partir fonts petroquímiques, la conversió de biomassa en productes químics valuosos és un camp actualment en desenvolupament. En aquest camp, una àmplia gamma d'enfocaments és fa servir. En aquesta tesi es presenten tres diferents noves estratègies per a la conversió de biomassa: i) producció de sucres fermentables (glucosa) a partir de: cel•lulosa, polpa produïda amb líquid iònic commutable i biomassa. Els sucres obtinguts es sotmeten a una fermentació microbiana; ii) desenvolupar una nova estratègia integrada per a produir un producte químic de valor afegit (5-acetoximetilfurfural) a partir de lignocelulosa, utilitzant acetat de cel•lulosa com a material de partida en lloc de cel•lulosa i aprofitant la solubilitat augmentada d'acetat de cel•lulosa; iii) millorar un producte químic de valor afegit tal com furfural cap a un producte final com el 1,5-pentanodienol per mitjà d'una reacció en cascada usant per primera vegada un catalitzador metàl•lic no noble. Per mitjà de la metodologia descrita, es produeix, respectivament, àcid làctic (amb ús estès com a precursor bioplàstic), 5-acetoximetilfurfural (un component estratègic amb una àmplia gamma de potencials conversions a productes químics valuosos) i 1,5-pentanodienol (1 producte final amb moltes aplicacions com resina o precursor bioplàstic).
Como alternativa a la producción química a partir fuentes petroquímicas, la conversión de biomasa en productos químicos valiosos es un campo actualmente en desarrollo. En este campo, una amplia gama de enfoques es usada. En esta tesis se presentan tres diferentes nuevas estrategias para la conversión de biomasa: i) producción de azúcares fermentables (glucosa) a partir de: celulosa, pulpa producida con líquido iónico conmutable y biomasa. Los azúcares obtenidos se someten entonces a ensayo para la fermentación microbiana; ii) desarrollar una nueva estrategia integrada para producir un producto químico de valor añadido (5-acetoximetilfurfural) a partir de lignocelulosa, utilizando acetato de celulosa como material de partida en lugar de celulosa y aprovechando la solubilidad aumentada de acetato de celulosa; iii) mejorar un producto químico de valor añadido tal como furfural en un producto final como el 1,5-pentanodienol por medio de una reacción en cascada usando por primera vez un catalizador metálico no noble. Por medio de la metodología descrita, se produce, respectivamente, ácido láctico (con uso extendido como precursor bioplástico), 5-acetoximetilfurfural (un componente estratégico con una amplia gama de potenciales conversiones a productos químicos valiosos) y 1,5-pentanodienol (un producto final con muchas aplicaciones como resina o precursor bioplástico).
As an alternative to chemical production from petrochemical sources, biomass conversion into valuable chemicals is a field in current development. In this field, a broad range of approaches is targeted. In this thesis, three new different strategies for the whole picture of biomass conversion are presented i) producing fermentable sugars (glucose) from: cellulose, pulp produced with switchable ionic liquid, and biomass. The obtained sugars are then tested for microbial fermentation; ii) developing a new integrated strategy to produce a valuable building block (5-acetoxymethylfurfural) from lignocellulose, using cellulose acetate as starting material rather than cellulose and taking benefit of cellulose acetate enhanced solubility; and iii) upgrading a building block such as furfural to an end product like 1,5-pentanedienol by means of cascade reaction using for the first time a non-noble metal catalyst. By means of the described methodology, is produced, respectively, lactic acid (with extended use as bioplastic precursor), 5-acetoxymethylfurfural (a strategic building block with a wide range of potential conversions to valuable chemicals), and 1,5-pentanedienol (an end product with a lot of applications as a resin or bioplastic precursor).

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Karpinskaitė, Inga. "Dekoratyvinių augalų, naudojamų energetiniams tikslams, augimas ir vystymasis." Bachelor's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100902_234957-54080.

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Tyrimo objektas – Lietuvos žemdirbystės instituto, energetinėje plantacijoje augantys augalai: sida (Sida hermaphrodita), drambliažolė (Miscanthus x gigantus), sachalininės ir japoninės rūgtys (Reynoutria sachalinensis FR., Reynoutria japonica Houtt.), geltonžiedis legėstas (Silphium perfoliatum L.) bei topinambai (Helianthus tuberosus L.). Tyrimo tikslas – pateikti dekoratyvinių augalų, naudojamų energetiniams tikslams, augimo ir vystymosi rodiklius. Uždaviniai: 1. Nustatyti augalų vegetacijos bei intensyvaus augimo pradžias. 2. Nustatyti azoto trąšų įtaką augalų augimui. 3. Įvertinti pasėlių būklę, vystymąsi ir nustatyti metinį biomasės derlių spalio mėnesį. 4. Įvertinti dekoratyvinių augalų auginimo energetiniams tikslams tinkamumą ir galimybes. Darbo metodai: augalai buvo vertinami pagal augalo aukštį (augalas matuojamas nuo žemės paviršiaus iki aukščiausiojo jo taško), stiebų skaičių (stiebų skaičius skaičiuojamas viename augalo kere) ir skersmenį (augalas matuojamas nuo žemės paviršiaus 15 cm). Skirtinga augalų rūšis matuojama pasirenkant iš kiekvieno laukelio po 5 augalus. Iš gautų duomenų vedamas vidurkis. Augalų žalia masė nustatoma nupjovus derlių ir jį pasvėrus. Augalų sausa masė nustatoma pasvėrus išdžiovintą žalią masę. Išanalizavus tyrimo duomenis paaiškėjo, jog iš visų tirtų augalų energetiniams tikslams tikslinga auginti sidas ir topinambus, kadangi sausos biomasės duomenimis konkurencingumo skalėje pirmumą tenka pripažinti būtent šiems augalams... [toliau žr. visą tekstą]
Object of the research comprises the plants growing in energetic plantation in Lithuanian Institute of Agriculture, namely Sida hermaphrodita, Miscanthus x gigantus, sachalin and Japanese species (Reynoutria sachalinensis FR., Reynoutria japonica Houtt.), Silphium perfoliatum L. and Helianthus tuberosus L.). Aim of the research is to provide the indicators related to growing and development of the plants used for energetic purposes. Tasks: 1. To establish the beginning of vegetation and intensive growing of the plants. 2. To establish the impact of nitrogen over the plant-growing. 3. To estimate the condition of crop, development as well as to establish annual yield in October. 4. To assess suitability and opportunities related to growing of decorative plants for energetic purposes. Work methods: the plants were assessed according to their height (a plant is measured from the soil surface up to the highest point), number of stems (number of stems calculated on one patula of the plant) and diameter (a plant is measured from the soil surface 15 cm). Different species of the plants were measured when selecting 5 plants from every field. An average was calculated referring to the data obtained. Green mass of the plants was established after having cut and having weighted the yield. Dry mass of the plants was established having weighted the dried green mass. Upon the analysis of the research data is was ascertained that out of all plants it is purposeful to grow Sida... [to full text]

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Vafek, Petr. "Úprava multicyklonu za biomasovým kotlem." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417450.

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The diploma thesis deals with multitube cyclone changes leading to improve separating efficiency of solid particles. The thesis begins with theoretical part, in which the attributes and types of solid particle separators focusing on cyclones are presented. The practical part begins with separating efficiency and pressure drop calculation of the specific multitube cyclone. Subsequently the separating problem is explained and the changes leading to eliminating this problem are presented and evaluated. In the last and main part of thesis the design project including piping design and fan choice is created.

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50

Petit, Martin. "Etude du comportement des espèces inorganiques dans une installation de gazéification de la biomasse : condensation des aerosols et dépôts." Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL019N/document.

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L’objectif de ce travail est d’analyser théoriquement et expérimentalement la condensation des espèces inorganiques dans une installation de gazéification de la biomasse. Lors de la gazéification de la biomasse, des espèces inorganiques sont volatilisées et se condensent lors du refroidissement du gaz de synthèse. Ces espèces sont problématiques pour le procédé et doivent être éliminées avant la synthèse des biocarburants. Une étude thermodynamique a précisé la nature et la répartition des espèces inorganiques qui sont volatilisées lors de la gazéification ainsi que des espèces qui se condensent lors du refroidissement. Un modèle de condensation des aérosols issus de la gazéification de la biomasse a ensuite été construit à partir d’une description mathématique des différents phénomènes mis en jeu (nucléation, croissance, agglomération et dépôts) Parallèlement un dispositif expérimental a été mis au point, construit et qualifié. Ce dispositif permet d’analyser la condensation d’une vapeur de KCl dans un écoulement pouvant comporter des particules de carbone se refroidissant à une vitesse de 1000 K/s. Les résultats expérimentaux obtenus ont mis en évidence une nucléation du KCl lors d’un refroidissement à 1000 K/s, la condensation de KCl sur les particules de carbone ainsi que le dépôt de KCl et des particules sur les parois. La condensation de KCl provoque une augmentation du diamètre aérodynamique des particules de carbone. La présence de particules dans l’écoulement permet de diminuer les dépôts de KCl aux parois de 25% à 40%. La comparaison de calculs simulant les expériences avec les données expérimentales a permis de quantifier les différents phénomènes et de valider le modèle. Enfin, des solutions ont été proposées pour limiter les dépôts de KCl aux parois des échangeurs dans une installation industrielle de gazéification de la biomasse
The aim of this work is to analyse theoretically and experimentally inorganic species conden- sation in a biomass gasification facility. During biomass gasification, some inorganic species are volatilised and then condense when the syngas cools down. These species can spoil the facility and thus have to be removed before the biodiesel synthesis. First, a thermodynamic study descri- bed the nature and distribution of inorganic species either volatilised during biomass gasification or condensed during cooling. Then an aerosol condensation model for biomass gasification has been developed using a mathematical description of the different phenomena involved (nuclea- tion, growth, agglomeration, deposition). Meanwhile, an experimental device (ANACONDA) has been built and qualified. This device was used to analyse KCl condensation on graphite particles as the gas cooled at 1000 K/s. Experimental results showed nucleation of new KCl particles du- ring the cooling, KCl condensation on graphite particles and deposition of KCl and particles on walls. KCl condensation causes an increase in graphite particle aerodynamic diameter. Graphite particles prevent wall deposit of KCl, which decreased from 40% to 25%. From the comparison of simulation and experimental results, the various phenomena could be quantified and the model validated. Finally, the model was used to propose solutions for limiting inorganic deposit on exchanger walls in a biomass-gasification industrial facility

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Dissertations / Theses on the topic 'Biomage'

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