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Pirólise de madeira tratada com CCA em reator de leito fixoJunges, Janaína 27 July 2015 (has links)
Os postes de madeira da rede de distribuição de energia elétrica são tratados com preservantes para aumentar sua vida útil. Dentre os diversos tipos de preservantes de madeira disponíveis no mercado, o mais utilizado é o arseniato de cobre cromatado (CCA), tendo em vista a sua elevada eficiência para preservar a madeira. A presença de metais nestes preservantes exige uma destinação adequada ao fim da vida útil do poste. O presente estudo propõe a utilização do processo de pirólise como uma alternativa para a destinação final dos postes de madeira removidos da rede de distribuição de energia elétrica. A pirólise da madeira tratada com CCA promove a liberação de compostos voláteis perigosos devido à presença dos metais (Cr/Cu/As) em sua composição. Com o intuito de minimizar estas emissões, reagentes de baixo custo (a base de cálcio) podem ser utilizados durante o processo pirolítico. Neste trabalho, foram avaliados os efeitos de diferentes parâmetros de operação (temperatura, tempo de isoterma, taxa de aquecimento, razão madeira/CaO e velocidade superficial) sobre a retenção dos metais no char da madeira tratada com CCA, bem como a influência dos compostos de cálcio sobre o poder calorífico do gás combustível gerado no processo de pirólise. A caracterização da madeira tratada com CCA indicou diferenças na composição química das frações testadas (C1-alburno externo, C2-alburno interno e C3-cerne), especialmente no teor de metais. As análises para a determinação da distribuição de metais indicaram que a concentração de compostos metálicos tende à zero na linha central do poste, de forma que a elevada concentração de metais está localizada na fração externa do poste. Na análise imediata, foi observado um teor mais elevado de cinzas na fração externa da madeira. Na Espectroscopia no Infravermelho com Transformada de Fourier (FTIR) a madeira com CCA apresentou bandas similares a de uma biomassa convencional. Na Análise Termogravimétrica (TGA), observaram-se picos próximos a 276 e 354 ºC, referentes à degradação térmica das hemiceluloses e da celulose, respectivamente. A energia de ativação determinada pelo método de Kissinger foi próxima a 156 kJ·mol-1. A Ea média calculada no método de Flynn-Wall-Ozama foi de aproximadamente 153 kJ·mol-1 para C1, 182 kJ·mol-1 para C2 e 170 kJ·mol-1 para C3. Os mecanismos de reação no estado sólido verificados no método de Criado foram comandados, em sua maioria, por processos de difusão. Sob condições controladas de operação, (temperatura, tempo de residência e vazão de ar) o carbonato de cálcio (CaCO3) foi calcinado visando a obtenção de óxido de cálcio (CaO) com elevada área superficial. Os ensaios preliminares de calcinação indicaram que o CaO com maior área superficial foi obtido a 850 ºC com um tempo de residência de 5 min. Na primeira série de ensaios de pirólise verificou-se que à medida que CaO foi adicionado ao sistema, a emissão de metais e a produção de óleo foram inferiores. No segundo lote dos ensaios de pirólise, os efeitos preponderantes para a retenção dos metais no char foram a granulometria elevada das partículas, a adição de CaO e a taxa de aquecimento. Devido à adição de CaO, obteve-se menor concentração de CO2 e foi produzido um gás combustível com poder calorífico próximo a 25 MJ·Nm-3. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-12-04T12:00:33Z
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Dissertacao Janaina Junges.pdf: 280866 bytes, checksum: b03a0ac95408121d4fa4ce8fd60796f8 (MD5) / Made available in DSpace on 2015-12-04T12:00:33Z (GMT). No. of bitstreams: 1
Dissertacao Janaina Junges.pdf: 280866 bytes, checksum: b03a0ac95408121d4fa4ce8fd60796f8 (MD5) / Companhia Paulista de Força e Luz, CPFL / Wooden poles of the electricity distribution network are treated with preservatives to increase their shelf life. Among the various types of wood preservatives available on the market, the most used is the chromated copper arsenate (CCA), due to its high efficiency for preserving wood. The presence of metals in these preservatives requires proper disposal at the end of pole life. This study proposes the use of pyrolysis process (under controlled conditions) as an alternative to wooden poles disposal after removed from the electricity distribution network. The pyrolysis of CCA treated wood promotes the release of dangerous volatile compounds due to the presence of metals (Cr/Cu/As) in its composition. In order to minimize these emissions, low cost reagents (based on calcium) can be used during the pyrolytic process. In this work, the effect of different operating parameters (temperature, residence time, heating rate, wood/CaO ratio and superficial velocity) on the retention of metals in the char was evaluated, as well as the influence of calcium compounds on the calorific value of the fuel gas generated in the pyrolysis process. The characterization of CCA treated wood indicated differences in the chemical composition of the tested fractions (C1-sapwood, C2- outer core and C3-cord), especially in the metal content. The metals distribution analysis indicated that the concentration of metallic compounds tend to zero at the center of the pole, so the high concentration of metal is located on the outer portion. In the proximate analysis, a higher ash content on the outer portion was observed. Fourier Transform Infrared Spectroscopy (FTIR) showed bands very similar to a conventional biomass. In Thermogravimetric Analysis (TGA) peaks centered at 276 and 354 ºC were observed, relating to thermal degradation of hemicellulose and cellulose respectively. The activation energy determined by the Kissinger method was approximately 156 kJ·mol-1. The mean activation energy by the Flynn-Wall-Ozama method was 153 kJ·mol-1 for C1, 182 kJ·mol-1 for C2 and 170 kJ·mol-1 for C3. The degradation reaction mechanism determined by using the Criado is mostly controlled by diffusion processes. Under controlled operating conditions (temperature, residence time and air flow) calcium carbonate (CaCO3) was heated in order to obtain calcium oxide (CaO) with a higher surface area. Preliminary tests indicated that the calcination of CaO with greater surface area was obtained at 850 ºC with a residence time of 5 min. In the first series of pyrolysis tests, as CaO was added to the system, lesser metals emission and oil yield were observed. In the second set of pyrolysis tests, the relevant effects identified on the retention of metals was the high particle size of the wood, the addition of CaO and the heating rate. Due to the addition of CaO, the CO2 concentration was reduced and it was produced a combustible gas with a calorific value close to 25 MJ·Nm-3.
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Pirólise de madeira tratada com CCA em reator de leito fixoJunges, Janaína 27 July 2015 (has links)
Os postes de madeira da rede de distribuição de energia elétrica são tratados com preservantes para aumentar sua vida útil. Dentre os diversos tipos de preservantes de madeira disponíveis no mercado, o mais utilizado é o arseniato de cobre cromatado (CCA), tendo em vista a sua elevada eficiência para preservar a madeira. A presença de metais nestes preservantes exige uma destinação adequada ao fim da vida útil do poste. O presente estudo propõe a utilização do processo de pirólise como uma alternativa para a destinação final dos postes de madeira removidos da rede de distribuição de energia elétrica. A pirólise da madeira tratada com CCA promove a liberação de compostos voláteis perigosos devido à presença dos metais (Cr/Cu/As) em sua composição. Com o intuito de minimizar estas emissões, reagentes de baixo custo (a base de cálcio) podem ser utilizados durante o processo pirolítico. Neste trabalho, foram avaliados os efeitos de diferentes parâmetros de operação (temperatura, tempo de isoterma, taxa de aquecimento, razão madeira/CaO e velocidade superficial) sobre a retenção dos metais no char da madeira tratada com CCA, bem como a influência dos compostos de cálcio sobre o poder calorífico do gás combustível gerado no processo de pirólise. A caracterização da madeira tratada com CCA indicou diferenças na composição química das frações testadas (C1-alburno externo, C2-alburno interno e C3-cerne), especialmente no teor de metais. As análises para a determinação da distribuição de metais indicaram que a concentração de compostos metálicos tende à zero na linha central do poste, de forma que a elevada concentração de metais está localizada na fração externa do poste. Na análise imediata, foi observado um teor mais elevado de cinzas na fração externa da madeira. Na Espectroscopia no Infravermelho com Transformada de Fourier (FTIR) a madeira com CCA apresentou bandas similares a de uma biomassa convencional. Na Análise Termogravimétrica (TGA), observaram-se picos próximos a 276 e 354 ºC, referentes à degradação térmica das hemiceluloses e da celulose, respectivamente. A energia de ativação determinada pelo método de Kissinger foi próxima a 156 kJ·mol-1. A Ea média calculada no método de Flynn-Wall-Ozama foi de aproximadamente 153 kJ·mol-1 para C1, 182 kJ·mol-1 para C2 e 170 kJ·mol-1 para C3. Os mecanismos de reação no estado sólido verificados no método de Criado foram comandados, em sua maioria, por processos de difusão. Sob condições controladas de operação, (temperatura, tempo de residência e vazão de ar) o carbonato de cálcio (CaCO3) foi calcinado visando a obtenção de óxido de cálcio (CaO) com elevada área superficial. Os ensaios preliminares de calcinação indicaram que o CaO com maior área superficial foi obtido a 850 ºC com um tempo de residência de 5 min. Na primeira série de ensaios de pirólise verificou-se que à medida que CaO foi adicionado ao sistema, a emissão de metais e a produção de óleo foram inferiores. No segundo lote dos ensaios de pirólise, os efeitos preponderantes para a retenção dos metais no char foram a granulometria elevada das partículas, a adição de CaO e a taxa de aquecimento. Devido à adição de CaO, obteve-se menor concentração de CO2 e foi produzido um gás combustível com poder calorífico próximo a 25 MJ·Nm-3. / Companhia Paulista de Força e Luz, CPFL / Wooden poles of the electricity distribution network are treated with preservatives to increase their shelf life. Among the various types of wood preservatives available on the market, the most used is the chromated copper arsenate (CCA), due to its high efficiency for preserving wood. The presence of metals in these preservatives requires proper disposal at the end of pole life. This study proposes the use of pyrolysis process (under controlled conditions) as an alternative to wooden poles disposal after removed from the electricity distribution network. The pyrolysis of CCA treated wood promotes the release of dangerous volatile compounds due to the presence of metals (Cr/Cu/As) in its composition. In order to minimize these emissions, low cost reagents (based on calcium) can be used during the pyrolytic process. In this work, the effect of different operating parameters (temperature, residence time, heating rate, wood/CaO ratio and superficial velocity) on the retention of metals in the char was evaluated, as well as the influence of calcium compounds on the calorific value of the fuel gas generated in the pyrolysis process. The characterization of CCA treated wood indicated differences in the chemical composition of the tested fractions (C1-sapwood, C2- outer core and C3-cord), especially in the metal content. The metals distribution analysis indicated that the concentration of metallic compounds tend to zero at the center of the pole, so the high concentration of metal is located on the outer portion. In the proximate analysis, a higher ash content on the outer portion was observed. Fourier Transform Infrared Spectroscopy (FTIR) showed bands very similar to a conventional biomass. In Thermogravimetric Analysis (TGA) peaks centered at 276 and 354 ºC were observed, relating to thermal degradation of hemicellulose and cellulose respectively. The activation energy determined by the Kissinger method was approximately 156 kJ·mol-1. The mean activation energy by the Flynn-Wall-Ozama method was 153 kJ·mol-1 for C1, 182 kJ·mol-1 for C2 and 170 kJ·mol-1 for C3. The degradation reaction mechanism determined by using the Criado is mostly controlled by diffusion processes. Under controlled operating conditions (temperature, residence time and air flow) calcium carbonate (CaCO3) was heated in order to obtain calcium oxide (CaO) with a higher surface area. Preliminary tests indicated that the calcination of CaO with greater surface area was obtained at 850 ºC with a residence time of 5 min. In the first series of pyrolysis tests, as CaO was added to the system, lesser metals emission and oil yield were observed. In the second set of pyrolysis tests, the relevant effects identified on the retention of metals was the high particle size of the wood, the addition of CaO and the heating rate. Due to the addition of CaO, the CO2 concentration was reduced and it was produced a combustible gas with a calorific value close to 25 MJ·Nm-3.
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Produção de gás de síntese a partir da glicerina / Syngas production from glycerolPeres, Ana Paula Gimenez, 1985- 16 August 2018 (has links)
Orientador: Maria Regina Wolf Maciel / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-16T03:15:43Z (GMT). No. of bitstreams: 1
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Previous issue date: 2010 / Resumo: Biodiesel (alquil éster) é um combustível limpo derivado de fontes renováveis, óleos vegetais ou gordura animal. Sabe-se que, aproximadamente, 10% em peso do óleo vegetal utilizado como insumo na produção de biodiesel é convertido em glicerina, de forma que existem grandes incentivos para a utilização deste subproduto. A pirólise da glicerina residual por sua vez é um processo com grande potencial para a produção de biocombustíveis como hidrogênio (H2) e gás de síntese (matéria prima para produção de combustíveis sintéticos via reação de Fischer-Tropsch) gerando portanto, produtos de alto valor agregado. Assim, neste trabalho, a pirólise foi realizada em um reator de leito fixo utilizando-se glicerina comercial e glicerina residual da produção de biodiesel dos Laboratórios de Otimização, Projeto e Controle Avançado (LOPCA) e de Desenvolvimento de Processos de Separação (LDPS). Primeiramente, foram realizados planejamentos fatoriais fracionários para a determinação das variáveis independentes (temperatura e tempo de reação, vazão de gás de arraste e volume de glicerina) mais significativos no processo. Sendo que o volume de glicerina foi a variável com menor significância, portanto foi excluída do processo. Posteriormente, realizaram-se os experimentos de acordo com o planejamento fatorial completo 23 (com mais três pontos centrais). Foram obtidos dois modelos codificados de primeira ordem que descrevem a conversão de glicerina residual em hidrogênio e gás de síntese em função da temperatura de reação, tempo e vazão de gás de arraste. De acordo com as condições advindas da aplicação da metodologia de superfície de resposta, altas conversões de glicerina em H2 e em gás de síntese, em torno de 45% mol/mol e 80% mol/mol, respectivamente, foram experimentalmente obtidas em: 850ºC, 30min e vazão do gás de arraste 50mL/min. No processo de pirólise da glicerina foram obtidos produtos líquidos, gasosos e cinzas. Em média, obtiveram-se conversões superiores a 85% v/v de glicerina para produtos gasosos, entre eles H2 e CO (gás de síntese) em maior quantidade. Além desses gases, foram encontrados CO2, metano, etileno, etano e propano. Já os produtos líquidos foram basicamente acetaldeído, acetona, metanol e etanol. Através dos cálculos de energia ficou claro que a produção de H2 a partir desse processo é viável energeticamente. Sendo que para um mol de glicerina processada a energia líquida da reação foi 293kJ. / Abstract : Biodiesel (alkyls esters) is a clean burning fuel derived from renewable lipid feedstock such as vegetable oil or animal fat. Glycerin is a by-product from the biodiesel production which represents nearly 10% of product total mass. As the biodiesel production is increasing there exist incentives to use the glycerin as raw material for other processes. The glycerin pyrolysis is a promising way to produce biofuels such as hydrogen and syngas (feedstock used in synthetic fuels production via Fisher-Tropsch reaction) and at same time avoids its accumulation in the environment. Glycerin pyrolysis was carried out in a fixed bed reactor filled with silica-quartz and/or alumina oxide. The raw material considered in this work was pure glycerin and crude glycerin from biodiesel production. Experimental designs were carried out in specific conditions to identify the impact of the main process variables. At first, a fractional factorial experimental design was chosen to analyze the most significant factors (reaction temperature, reaction time, glycerin quantity and flow rate of carrier gas) on the conversion glycerin to hydrogen and syngas. The glycerin quantity was the least significant factor, so it was excluded from further investigation. Afterwards, the experiments were carried out according to a 23 complete factorial design plus three central points. Two first-order models were obtained to predict the crude glycerin conversion in hydrogen and syngas as a function of reaction temperature, reaction time and flow rate of carrier gas. From the surface methodology analysis, high conversions of glycerin into hydrogen and syngas, around 45% mol/mol and 85% mol/mol, respectively, can be obtained under the following conditions 850 º C, 30 min and flow carrier gas, 50ml/min. The best glycerin conversion to gas products was 80% v/v of glycerin. The main gás products were H2 and CO. Besides these gases, CO2, CH4, C2H4 and C3H8 were also obtained in smaller proportions. The liquid product compositions were methanol, ethanol, acetone and acetaldehyde. Through the energy calculations, it becomes clear that production of H2 from this process is energetically feasible. For one mole of glycerol, computed net energy of the reaction was around 293kJ. / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química
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Design, modelling and construction of a scalable dual fluidised bed reactor for the pyrolysis of biomassSwart, Stephen David 26 November 2012 (has links)
The pyrolysis of biomass is a thermochemical process in which woody biomass is converted to several high-value products such as bio-oil, bio-char and syngas. The forestry sector has shown particular interest in this process as a large quantity of biomass is produced as an underutilised by-product in this sector annually. Dual fluidised beds (DFBs) have been identified as a feasible reactor system for this process. However, little attention has been given to the optimisation or to the design of a scalable DFB for the pyrolysis of biomass process. Therefore, the objective of the current project was the design, modelling and construction of a scalable dual fluidised bed system for the pyrolysis of biomass. In order to achieve this objective, several tasks were performed, which included the following: <ul> <li> A literature study was done in order to obtain a theoretical foundation for the current project.</li> <li> A novel dual fluidised bed reactor system was designed, which included the block flow diagram and the process and instrumentation diagram for the system.</li> <li> A cold unit of the system was built in order to test the performance of the system.</li> <li> A comprehensive model for the system was developed, which included mass and energy balance considerations, hydrodynamics and reaction kinetics.</li> <li> A complete pilot-scale system of the proposed design was built and tested at the University of Pretoria.</li></ul> Solids are heated by means of combustion reactions in one of the fluidised beds in the proposed dual fluidised bed design. An overflow standpipe is then used to transport the solids to a second fluidised bed in order to provide the energy required for the endothermic pyrolysis reactions. The cooler solids are then fed back to the combustion fluidised bed by means of a screw-conveyor, creating a circulating system. A two-stage model was used to model the pyrolysis reactions. In this model, the wood is converted to bio-char, syngas and tar compounds. The tar compounds are the desired product as they can be condensed to form liquid bio-oil. However, these compounds undergo a second reaction in the gas phase in which they are converted to bio-char and syngas. It is therefore necessary to quench these gases rapidly in order to maximise the yield of bio-oil obtained from the system. Bio-oil is a source of many high-value chemicals and can also be upgraded to produce liquid bio-fuels. A portion of the syngas is recycled back to the pyrolysis fluidised bed in order to fluidise the bed. In this way, oxygen is prevented from entering the pyrolysis fluidised bed, which would cause the biomass in the bed to undergo combustion rather than pyrolysis. The operating temperatures of the combustion and pyrolysis fluidised beds were optimised at 900°C and 500°C respectively. A cold unit of the system was built at the Agricultural Research Service in Wyndmoor, Pennsylvania, USA. From the experiments performed on this unit it was found that the solid transport mechanism designed during the project is suitable for the pyrolysis of biomass process. In addition, the solids circulation rate between the two beds was easy to control, which is necessary in order to maximise the yield of bio-oil obtained from the system. A pilot-scale unit of the dual fluidised bed design was built in order to finalise the design and ensure that it could be scaled up. This system included all the downstream units, which had to be designed for the dual fluidised bed system. Several cold-run experiments were also performed on the pilot-scale system in order to ensure that it would perform as required during operation. It was found that the combustion fluidised bed could be fluidised as required and that the circulation of solids between the combustion and pyrolysis fluidised beds functioned well and could be easily controlled. Therefore, it was concluded that the proposed dual fluidised bed system is suitable for the pyrolysis of biomass process and is a feasible reactor system for the large-scale pyrolysis of biomass. The large-scale operation of the proposed dual fluidised bed system offers several advantages, particularly within the forestry sector. These advantages have important implications, as follows: <ul> <li> The current research offers the opportunity for the forestry sector to shift its focus from the production of traditional wood products, such as pulp and paper, to products such as specialised chemicals.</li> <li> The bio-oil produced in the dual fluidised bed system can be upgraded to renewable liquid fuels, which may help reduce the dependence of the infrastructure on fossil fuels.</li> <li> The dual fluidised bed system provides an opportunity for capturing and removing CO2 from the atmosphere in the form of bio-char. It is therefore considered to be a carbon-negative process, and may help reduce the concentration of greenhouse gases.</li> <li> The bio-char produced in the dual fluidised bed system can be used to feed nutrients back to plantation floors in the forestry sector, thereby aiding the growth of further plantations.</li></ul> Copyright / Dissertation (MEng)--University of Pretoria, 2013. / Chemical Engineering / unrestricted
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Biomass Fast Pyrolysis Fluidized Bed Reactor: Modelling and Experimental ValidationMatta, Johnny January 2016 (has links)
Of the many thermochemical conversion pathways for utilizing biomass as a renewable energy source, fast pyrolysis is a promising method for converting and upgrading carbonaceous feedstocks into a range of liquid fuels for use in heat, electricity and transportation applications. Experimental trials have been carried out to assess the impact of operational parameters on process yields. However, dealing with larger-scale experimental systems comes at the expense of lengthy and resource-intensive experiments. Luckily, the advances in computing technology and numerical algorithm solvers have allowed reactor modelling to be an attractive opportunity for reactor design, optimization and experimental data interpretation in a cost-effective fashion. In this work, a fluidized bed reactor model for biomass fast pyrolysis was developed and applied to the Bell’s Corners Complex (BCC) fluidized bed fast pyrolysis unit located at NRCan CanmetENERGY (Ottawa, Canada) for testing and validation. The model was programmed using the Microsoft Visual Basic for Applications software with the motivation of facilitating use and accessibility as well as minimizing runtime and input requirements. The application of different biomass devolatilization schemes within the model was conducted, not only for biomass fast pyrolysis product quantity but also liquid product composition (quality), to examine the effect of variable reaction kinetic sub-models on product yields. The model predictions were in good agreement with the results generated from the experimental work and mechanism modifications were proposed which further increased the accuracy of model predictions. Successively, the formulation of the modelled fluid dynamic scheme was adapted to study the effect of variable hydrodynamic sub-models on product yields for which no significant effect was observed. The work also looked into effect of the dominant process variables such as feedstock composition, bed temperature, fluidizing velocity and feedstock size on measurable product outputs (bio-oil, gas and biochar) and compared the results to those generated from the experimental fast pyrolysis unit. The ideal parameters for maximizing bio-oil yield have been determined to be those which: minimize the content of lignin and inorganic minerals in the feedstock, maintain the dense-bed temperature in a temperature range of 450-520 ºC, maximize the fluidization velocity without leading to bed entrainment, and limit the feedstock particle size to a maximum of 2000 μm.
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Development of an alternative fuel from waste of used tires by pyrolysis / Développement d'un carburant alternatif à partir des déchets de pneus usagés par pyrolyseAlkhatib, Radwan 06 November 2014 (has links)
L'objectif de ce travail est de valoriser des déchets de pneus usagés par pyrolyse afin d'obtenir un nouveau carburant comparable avec le gazole suivant la norme EN590. L'obtention de ce carburant était réalisée via l'optimisation des conditions de pyrolyse qui sont la température, la vitesse de chauffage (puissance de la résistance électrique) et du débit d'azote. Le rôle de l'azote est limité à purger le réacteur avant le début de la pyrolyse pour 30 minutes système. Le carburant produit est comparable au gazole avec un pouvoir calorifique de 45 MJ/kg, une densité de 0,85 et une teneur en goudron 7%. / The objective of this work is to get alternative fuel comparable with the available diesel in the market following the EN590. The fuel getting was via optimization of pyrolysis conditions which are temperature, heating rate (power of electrical resistance) and inert gas flow rate. The optimum values are 465°C, 650 Watts and without inert gas flow rate. Inert gas role is limited to purge the system for 30 minutes before start the pyrolysis to get rid of oxidative gases. The obtained product is comparable with the diesel as it has GCV 45 KJ/kg, low density of 0,85 and 7% tar content.
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The Catalytic Pyrolysis of BenzeneEscue, Richard Byrd 08 1900 (has links)
This thesis resulted from tests conducted to determine the nature of benzene pyrolysis during chemical reactions created to increase the stability of gasoline.
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Characterization of potential source rocks of the Prince Albert, Whitehill and Collingham formations in the Laingsburg sub-basin, South AfricaFerreira, Janine Connie January 2014 (has links)
>Magister Scientiae - MSc / The present research deals with the characterization of the Lower Ecca Group in terms of sedimentology, mineralogy and organic geochemistry. A field study was conducted in order to characterize the sedimentology and thereby determine the environments of deposition of the Prince Albert, Whitehill and Collingham Formations. In addition, shale samples were subjected to geochemical and mineralogical analyses so as to ascertain its source rock properties. The study utilized X-ray diffraction (XRD), scanning electron microscopy with an energy dispersive spectrometer (SEM-EDS), total organic carbon (TOC) and Rock-Eval pyrolysis to determine the mineralogy and organic geochemistry of shale from the formations under investigation. The sedimentological investigation revealed that the upper Prince Albert Formation is dominated by shale with thin beds of carbonate. These shales are interpreted to have been deposited by suspension settling in a marine environment which was occasionally interrupted by deposition of carbonates that form in a shallow marine environment. The overlying Whitehill Formation consists predominantly of carbonaceous shale with relatively more resistant shale beds also present. The fine sediments are interpreted to have been deposited from suspension settling under anoxic bottom conditions which would favor the preservation of organic rich material. Deposition of the Whitehill Formation was followed by the Collingham Formation which is dominated by rhythmic deposits of shale and sandstone that are occasionally interrupted by tuff layers. The clay size sediments are interpreted to have been deposited from suspension settling which are interbedded with low density turbidite current deposits in a marine environment. Based on the findings of the field study, it is apparent that the Prince Albert and Collingham Formations were deposited in marine environments, with the Whitehill Formation being deposited in an anoxic environment. These environments are known to be dominated by phytoplanktonic organisms and algal debris, and as such shales deposited in these environments contain predominantly Type I (derived from algae) and II kerogen (derived from plankton). It can therefore be postulated that Type I and II kerogens are the dominant constituents of organic matter in the Lower Ecca Group shales. Mineralogically, the shales consist chiefly of kaolinite, smectite and illite clay minerals, which are derived from a combination of weathering of feldspars, and the alteration of other clay minerals. The latter being inferred from the existence of albite in all the studied shale samples, pyroclastic material observed in the field, as well as the occurrence of alteration along clay mineral edges.
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Molecular mechanisms and control of cellulose carbonization for efficient production of levoglucosan / セルロース炭化の分子機構解明とその制御によるレボグルコサンの高効率生産Nomura, Takashi 24 May 2021 (has links)
京都大学 / 新制・課程博士 / 博士(エネルギー科学) / 甲第23394号 / エネ博第421号 / 新制||エネ||80(附属図書館) / 京都大学大学院エネルギー科学研究科エネルギー社会・環境科学専攻 / (主査)教授 河本 晴雄, 教授 髙野 俊幸, 准教授 奥村 英之 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DFAM
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Querying early product chemistry in a complex process: A cold molecular beam approach for triglyceride pyrolysis: Cold molecular beam study of Triglycerides pyrolysis chemistryJanuary 2020 (has links)
archives@tulane.edu / A cold molecular beam approach has been pioneered to investigate the pyrolysis reactions of triglycerides (TGs) as a function of temperature. Traditionally, an established repertoire of laser techniques is utilized for multiple species present, which has been extensively used for a detailed study of specifically targeted species that are often novel and reactive. Instead, we have applied these methods for the mass characterization of numerous product species as they appeared. Unlike traditional batch reactor studies of pyrolysis, where terminal products are identified and characterized generally using GC/MS methods, herein, product analysis was conducted in real time. Experiments were performed by recording mass spectra as a function of increasing sample temperature. For clearer results and interpretation, most studies employed model TGs containing a single fatty acid, such as oleic or stearic acid. Soft photoionization was conducted using 118 and 266 nm laser-based pulses. Time-of-flight mass spectroscopy (TOF-MS) was conducted after each photoionization pulse. Several novel direct observations include 1) the observation of initial cracking temperatures and the formation of non-aromatic and aromatic products; 2) the determination of key factors for pyrolysis—fatty acid detachment from the glycerol backbone and subsequent fatty acid pyrolysis; 3) the growth of C6 and C7 fragments as an important precursor for following association reactions. The use of 266 nm pulses exclusively facilitated the sensitive and selective photoionization of aromatic products and, thus, the thorough examination of the evolving aromatic products. Unlike the batch reactor studies of terminal products, the molecular beam studies of aromatic products revealed the evolution to a small number of selective and relatively massive polycyclic aromatic hydrocarbons (PAH). It is deduced that in a batch reactor, these undetected products ultimately lead to solids and tars that are difficult to analyze. Our investigation revealed that hydrogen addition showed some effectiveness in inhibiting formation of large / 1 / Ibrahi M. Alhroob
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