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Příprava a základní chemická a fyzikální charakterizace biouhlu z pšeničných otrub / Preparation and basic chemical and physical characterization of biochar from wheat branZouharová, Kamila January 2020 (has links)
At present, the extraction of biochar and its use is a much-discussed topic in the chemical and research fields. The use of biochar is very often declined in the areas of agriculture, waste management, environmental improvement and the fight against global warming. In addition to these sectors, the topic of biochar is also addressed in the production of bio-diesel and bio-oil. Due to the current use of secondary products during biotechnological processes, the presented theoretical and practical study focused on the issue of obtaining biochar from bran by pyrolysis at different temperatures. Part of the practical part was the extraction of biochar from bran and its subsequent analysis, which could be used to characterize biochar obtained from bran by pyrolysis physically and chemically. The characterization of bran biochar was solved by various analytical methods. These techniques yielded, for example, pH, conductivity, particle distribution, elemental composition of biochar, porosity and content of polycyclic aromatic hydrocarbons. Thanks to this study, the properties of biochar and its possible applications in everyday life were characterized in detail. Given the very promising use of biochar obtained from bran, it can be said that this will be a very desirable topic for the future.
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Tratamento de efluente da indústria de cosméticos via reagente de Fenton e adsorção / Cosmetic wastewater treatment by Fenton’s reagent and adsorptionPereira, Lisiée Manzoli Gonçaves 04 April 2018 (has links)
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Previous issue date: 2018-04-04 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / The effluent generated by the cosmetic industries, from industrial processes, tank washes and disposal of failed batches, are highly recalcitrant due to their complex chemical composition. The deposition of such liquids into water bodies must follow a series of environmental parameter values established by local and federal legislation so that they do not negatively affect the receiving environment and its ecosystems. Traditional wastewater treatment methods sometimes fail to satisfactorily remove their contaminating potential. Therefore, this work aims at integrating two treatment technologies, Fenton’s reagent and adsorption, in order to achieve maximum
removal efficiency in the values of environmental and water quality control parameters. Wastewater from a cosmetics industry in the metropolitan area of Goiania (state of Goias, Brazil) was used as object of this study. The environmental parameters analyzed were: color (via absorbance analysis), total iron, organic matter (via chemical oxygem demand analysis), total phenols, pH, turbidity, conductivity, dissolved oxygen, initial and residual H2O2 and total solids. They were analyzed on the pretreated wastewater, after the Fenton’s reagent treatment, after adsorption, and after the combined processes. The adsorbent was characterized by elemental analysis (CHN), thermogravimetry (TG/DTA), adsorption and desorption of N2 and infrared spectroscopy. In the Fenton’s reagent treatment, factorial design 23 was performed for the factors: Fe2+ and H2O2 concentrations and pH, in order to outline the process parameters. From these data, other Fenton assays were performed by opening Fe2+, H2O2 and pH concentration bands to evaluate their influence on the removal of the environmental parameters mentioned above. The best results were obtained in Fe2+ 184.21 mg L-1; H2O2 concentration at 1300 mg L-1, and pH at 3.5. Subsequently, the wastewater treated via Fenton’s reagent was subjected to the adsorption process, in which seven types of activated carbon were tested. The activated charcoal which presented the best efficiency at removing environmental parameter values was submitted to kinetic tests at different temperatures and contact times. The equilibrium time was reached in 16 minutes (tested in the range of 4min to 24h), and for the different temperatures it was observed that its increase did not contribute significantly to the process efficiency (tested in the range of 20 to 60ºC). The integration of the two technologies presented the following percentages of global variation: chemical oxygem demand: -73.58%; turbidity: -97.65%; conductivity: -5.36%; dissolved oxygen: + 141.24%; total phenols: -81.77%; total iron: -69.97%; hydrogen peroxide: -97.78%; total solids: -46.37%; total fixed solids: -30.57%; total volatile solids: -46.65%; absorbance at 200 nm: -36.38%; absorbance at 400 nm: -77.37%. The pH, total iron and hydrogen peroxide parameters were controlled in the Fenton’s reagent process. / O efluente gerado pelas indústrias de cosméticos, proveniente de processos industriais, lavagens de tanques e descarte de lotes falhos, são altamente recalcitrantes devido à sua complexa composição química. A deposição de tais líquidos em corpos d’água deve seguir uma série de valores de
parâmetros ambientais legislados para que não afetem de maneira negativa os meios receptores e seus ecossistemas. Por vezes, os métodos tradicionais de tratamento de efluentes não conseguem remover seu potencial poluidor de maneira satisfatória. Assim, a proposta deste trabalho foi integrar duas tecnologias de tratamento, reagente de Fenton e adsorção, a fim de alcançar máxima eficiência de remoção nos valores dos parâmetros de controle ambiental. O efluente real de uma indústria de cosméticos na região metropolitana de Goiânia foi utilizado como objeto de estudo. Os parâmetros ambientais analisados foram cor (por absorbância), ferro total, matéria orgânica (por demanda química de oxigênio), fenóis totais, pH, turbidez, condutividade, oxigênio dissolvido, H2O2 inicial e residual e sólidos totais, nos efluentes pré-tratado, pós-Fenton e final (pós-Fenton seguido de adsorção). O adsorvente foi caracterizado por análise elementar (CHN), termogravimetria (TG/DTA), adsorção e dessorção de N2 e espectroscopia de infravermelho. Para dar início ao tratamento via reagente de Fenton, foi realizado planejamento fatorial 23, para os fatores, concentração de Fe2+, concentração de H2O2 e valor de pH, a fim de delinear os parâmetros do processo. Destes dados, outros ensaios de Fenton foram realizados abrindo-se faixas de concentração de Fe2+, H2O2 e valor de pH, para avaliar a influência dos mesmos na remoção dos parâmetros ambientais supracitados. Os melhores resultados foram obtidos em concentração de Fe2+ 184,21 mg.L-1; concentração de H2O2 em 1300 mg L-1, e pH em 3,5. Em seguida, o efluente pós Fenton foi utilizado no processo de adsorção, em que foram testados sete tipos de carvões ativados nos ensaios. Para o carvão ativado que apresentou melhores resultados para os parâmetros ambientais supracitados, foram realizados testes cinéticos em batelada e com diferentes temperaturas. Na cinética, o tempo de equilíbrio foi atingido em 16 minutos (teste na faixa de 4min-24h), e para as diferentes temperaturas observou-se que o aumento da mesma não contribuiu significativamente na eficiência do processo (teste na faixa de 20 - 60ºC). A integração das duas tecnologias apresentou os seguintes percentuais de variação globais: demanda química de oxigênio: -73,58%; turbidez: -97,65%; condutividade: -5,36%; oxigênio dissolvido: +141,24%; fenóis totais: -81,77%; ferro total: -69,97%; peróxido de hidrogênio: -97,78%; sólidos totais: -46,37%; sólidos fixos totais: -30,57%; sólidos voláteis totais: -46,65%; absorbância em 200nm: -36,38%; sbsorbância em 400nm: -77,37%.
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Développement de mélanges chargés en poudres d'aluminure de titane pour moulage par injection et applications aéronautiques / Development of mixtures of polymers loaded whith titanium aluminide alloys - Injection molding and aerospaceTourneroche, Paul 22 March 2016 (has links)
La réduction de l’impact des activités humaines sur l’environnement est au sujet de nombreux programmes de recherche. Ainsi, dans le domaine du transport aérien a été créé le projet Clean-Sky, regroupant les thèmes de recherche associés. La thèse, partie de ce dernier, a pour objectif de réduire l’impact environnemental de la production de composants en alliages avancés à base de Titane. La production actuelle ayant une empreinte écologique non négligeable, un procédé de fabrication alternatif est étudié, il s’agit du moulage par injection de poudres métalliques. La première partie de cette consiste donc en la recherche d’une formulation de mélange optimale parmi les solutions classiques et innovantes. Elles sont triées en fonction de leurs aptitudes, déterminées par caractérisations physico-chimiques, à assurer le bon déroulement de chaque étape du procédé. Un nombre réduit de solution étant ainsi dégagé, il s’agit de passer aux étapes d’injection, de déliantage et de frittage. Plusieurs géométries de pièces sont testées dans chacun de ces cas, afin de valider l’adaptation aux différentes contraintes imposées. Lors de ces trois phases, des analyses physico-chimiques complètes permettent de mettre en avant la ou les formulations les plus aptes à permettre la production de ces composants. Une fois la solution fixée, chaque étape du procédé est optimisées, afin de faciliter le transfert industriel et d’assurer la rentabilité du nouveau processus de fabrication. Ces travaux de doctorat ont permis de mettre en avant deux formulations, répondant aux critères définis en début de thèse. Les étapes de mélange, injection, déliantage et frittage ont été optimisées et le transfert industriel est possible. / Reducing the ecological footprint of human activities is, today, the aim of most of the research programs. In Europe, the « Clean Sky » project funds research activities to make air transport « greener ». This PhD, being part of it, is about improving production of Titanium Aluminide based components. Nowadays production having a strong environmental impact, an alternative way has been investigated: metal injection molding. The first step of this work was focused on a bibliographic study, to select relevant, common and innovative mixtures to be used in the process. Throughout the process, these mixtures have been tested, physically and chemically analyzed, to get data about the optimal mixture. Several components geometries have been tested, during injection, debinding, and sintering steps. Once the mixture(s) chosen, process’ parameters have been optimized to make industrial transfer easier, and lower its overall cost. The developments achieved during this PhD led to two qualified mixtures, and optimized mixing, molding, debinding and sintering steps.
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An?lise da viabilidade de aplica??o de res?duos da constru??o civil da Regi?o Metropolitana de Campinas em argamassas de uso geral por m?todo multicrit?rios / Analysis of the feasibility of applying construction waste from the Metropolitan Region of Campinas to mortars of general use by multi-criteria methodPetitto, R?gia Mara 21 June 2017 (has links)
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Previous issue date: 2017-06-21 / The objective of this work was to characterize the recycled aggregates generated in the metropolitan region of Campinas and to test its application in the production of mortars for general use. From a qualitative approach, with an exploratory objective, the surveys of the current legislation and legal requirements imposed to solid waste management and the panorama of this management in the metropolitan region of Campinas were carried out. The six recycling plants for the disposal of construction waste (RCC) generated in the implanted municipalities were identified and, based on the data collected, a map with the geographic location of these plants was elaborated. After the sample collection, with a quantitative approach of applied nature and exploratory objective, analyzes of the physical characteristics were made (grain size composition, 75 ?m sieve material, water absorption, clay cladding content and friable materials, Specific mass and organic impurity) and chemical (soluble salts and organic matter content by fire loss) of these materials. All the analyzed aggregates presented satisfactory results in the granulometric composition and water absorption tests. Regarding the content of fine material (less than 75 ?m), clay content and friable materials and organic impurities, few samples could be accepted for use recommended by the Brazilian Association of Technical Standards (ABNT). The analysis of the soluble salts content would also make it impossible to accept the aggregate of some suppliers. With the replacement of natural aggregate by the recycled aggregates, mortars with a 1: 3 dash (cement: aggregate) were prepared, and 20 and 40% of the natural aggregate were replaced. The characteristics of the mortars in the fresh state (water retention, incorporated air content, mass density) and hardened (water absorption by capillarity, capillary coefficient, compressive strength, flexural tensile strength and apparent specific mass in the Hardened state). From the results obtained, the analytical Hierarchy Process (AHP) methodology showed the content of incorporation of the recycled aggregate in the production of general purpose mortars composed of cement and sand. For the application of this method, weights were assigned to punctuated criteria related to the physical and mechanical performance of mortars and environmental criteria related to the exhaustion of natural resources and transport distance. The best result was found in mortar with a 20% substitute content of mixed recycled aggregate by municipal unit from Campinas, but it is not possible to observe a tendency to obtain better results in mortars with lower substitution content, nor exclusively by mortars with mixed recycled aggregates. / O presente trabalho teve por objetivo caracterizar os agregados reciclados gerados na regi?o metropolitana de Campinas e testar sua aplica??o na produ??o de argamassas para uso geral. A partir de uma abordagem qualitativa, com objetivo explorat?rio, foram realizados os levantamentos da legisla??o vigente e exig?ncias legais impostas ? gest?o dos res?duos s?lidos e do panorama desta gest?o na regi?o metropolitana de Campinas. As seis usinas recicladoras para destina??o dos res?duos de constru??o civil (RCC) gerados nos munic?pios implantadas foram identificadas e, a partir dos dados coletados, elaborou-se um mapa com a localiza??o geogr?fica destas usinas. Ap?s a coleta de amostras, com abordagem quantitativa de natureza aplicada e objetivo explorat?rio, foram realizadas an?lises das caracter?sticas f?sicas (composi??o granulom?trica, teor de material passante na peneira de 75 ?m, absor??o de ?gua, teor de torr?es de argila e materiais fri?veis, massa espec?fica e impureza org?nica) e qu?micas (sais sol?veis e teor de mat?ria org?nica por perda ao fogo) destes materiais. Todos os agregados analisados apresentaram resultados satisfat?rios nos ensaios de composi??o granulom?trica e absor??o de ?gua. J? quanto ao teor de material fino (menor que 75 ?m), teor de torr?es de argila e materiais fri?veis e impurezas org?nicas, foram poucas as amostras que poderiam ser aceitas para o emprego recomendado pela Associa??o Brasileira de Normas T?cnicas (ABNT). A an?lise do teor de sais sol?veis tamb?m inviabilizaria a aceita??o do agregado de alguns fornecedores. Com a substitui??o de agregado natural pelos agregados reciclados foram preparadas argamassas com tra?o de 1:3 (cimento:agregado), e substitui??o de 20 e 40% do agregado natural. Foram determinadas as caracter?sticas das argamassas no estado fresco (reten??o de ?gua, teor de ar incorporado, densidade de massa) e endurecido (absor??o de ?gua por capilaridade, coeficiente de capilaridade, resist?ncia ? compress?o, resist?ncia ? tra??o na flex?o e massa especifica aparente no estado endurecido). A partir dos resultados obtidos verificou-se, por aplica??o do m?todo de avalia??o multicrit?rios, com a metodologia Analytic Hierarchy Process (AHP), o teor de incorpora??o do agregado reciclado na produ??o de argamassas de uso geral compostas por cimento e areia. Para a aplica??o deste m?todo foram atribu?dos pesos a crit?rios pontuados ligados ao desempenho f?sico e mec?nico das argamassas e crit?rios ambientais ligados ao esgotamento dos recursos naturais e dist?ncia de transporte. O melhor resultado foi encontrado na argamassa com teor de substitui??o de 20% de agregado reciclado misto da unidade municipal de Campinas, mas n?o ? poss?vel observar tend?ncia de obter melhores resultados em argamassas com menor teor de substitui??o, nem t?o pouco exclusivamente por argamassas com agregados reciclados mistos.
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Caractérisation d'un nouveau matériau et valorisation dans les barrières perméables réactives / Characterisation of a new material and its valorization in a permeable reactive barriersZakaria, Khaled 14 December 2012 (has links)
La valorisation des déchets industriels est de nos jour un défit international ayant des intérêts économiques et environnementaux. Dans ce cadre, l’entreprise Solvay travail sur la gestion de ses déchets et plus particulièrement ceux produits de la fabrication du carbonate de sodium « soude ». Ils sont actuellement stockés dans des bassins de décantation. Cependant, des contraintes règlementaires sont récemment apparues limitant ainsi la construction de nouveaux bassins. La valorisation de ces déchets est par conséquent impérative pour l’entreprise. Plusieurs voies de valorisation sont envisageables, notamment le recours à des nouveaux procédés qui permettraient d’en produire de nouveaux matériaux.En effet, un nouveau matériau issu des déchets industriels appelé « Gel d’Apatite » fait l’objet de ce travail de thèse. L’objectif est de caractériser le Gel d’Apatite et de proposer et d’étudier une voie permettant sa valorisation. Ce matériau est constitué principalement d’hydroxyapatite et de l’eau. Il se distingue par un comportement thixotropique et par sa capacité de rétention des métaux lourds. Cette dernière propriété a permis d’envisager sa valorisation dans la dépollution et la protection des nappes phréatiques. La voie étudiée dans ce travail de recherche est la valorisation du Gel d’Apatite dans les Barrières Perméables Réactives « BPR(s)»; technique passive de traitement des eaux souterraines in-situ.La finalité de ces travaux de recherche serait de dresser un cahier de charge du Gel d’Apatite et de définir un mélange conforme au mode de valorisation étudié / The valorization of industrial wastes is nowadays a worldwide challenge that offers several environmental and social interests. In some fields this valorization allows the preservation of natural resources and the releasing of spaces devoted to the wastes storage. Further, it allows developing of new innovative materials and low-cost products. Consequently industries industries have followed these guidelines. A collaborative investigation has been established with Solvay and Ecole Centrale de Lille in order to work on this topic.A new material: hydroxyapatite gel, is thus developed from non-toxic wastes in an industrial research laboratory. This material is composed by hydroxyapatite and water. It is characterized by its capacity to retain heavy metal by ion exchange. This particular characteristic led to consider its valorization in the water pollution control as the permeable reactive barrier (PRB) in particular. In deed, the permeable reactive barrier is a passive technique of in situ groundwater treatment.The results from this study were useful for a better planning of Permeable Reactive Barriers (PRB). The latter requires a high permeability to ensure groundwater flow and a high retention capacity for heavy metals
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Etude et développement de points mémoires résistifs polymères pour les architectures Cross-Bar / Development and Study of Organic Polymer Resistive Memories For Crossbar ArchitecturesCharbonneau, Micaël 19 January 2012 (has links)
Ces dix dernières années, les technologies de stockage non-volatile Flash ont joué un rôle majeur dans le développement des appareils électroniques mobiles et multimedia (MP3, Smartphone, clés USB, ordinateurs ultraportables…). Afin d’améliorer davantage les performances, augmenter les capacités et diminuer les coûts de fabrication, de nouvelles solutions technologiques sont aujourd’hui étudiées pour pouvoir compléter ou remplacer la technologie Flash. Citées par l’ITRS, les mémoires résistives polymères présentent des caractéristiques très prometteuses : procédés de fabrication à faible coût et possibilité d’intégration haute densité au dessus des niveaux d’interconnexions CMOS ou sur substrat souple. Ce travail de thèse a été consacré au développement et à l'étude des mémoires résistifs organiques à base de polymère de poly-méthyl-méthacrylate (PMMA) et de molécules de fullerènes (C60). Trois axes de recherche ont été menés en parallèle: le développement et la caractérisation physico-chimique de matériaux composites, l’intégration du matériau organique dans des structures de test spécifiques et la caractérisation détaillée du fonctionnement électrique des dispositifs et des performances mémoires. / Over the past decade, non-volatile Flash storage technologies have played a major role in the development of mobile electronics and multimedia (MP3, Smartphone, USB, ultraportable computers ...). To further enhance performances, increase the capacity and reduce manufacturing costs, new technological solutions are now studied to provide complementary solutions or replace Flash technology. Cited by ITRS, the polymer resistive memories present very promising characteristics: low cost processing and ability for integration at high densities above CMOS interconnections or on flexible substrate. This PhD specifically focused on the development and study of composite material made of Poly-Methyl-Methacrylate (PMMA) polymer resist doped with C60 fullerene molecules. Studies were carried out on three different axes in parallel: Composite materials development & characterization, integration of the organic material in specific test structure and advanced devices and finally detailed electrical characterization of memory cells and performances analysis.
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