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Separation Of Organic Acids And Lignin Fraction From Bio-Oil And Use Of Lignin Fraction In Phenol-Formaldehyde Wood Adhesive ResinSukhbaatar, Badamkhand 09 August 2008 (has links)
Bio-oil produced from biomass by the fast pyrolysis method is promising as a renewable fuel and as sources of industrial chemicals. In this study, lower cost separation methods of organic acids such as acetic and formic acids and pyrolytic lignin fraction present in bio-oil were investigated to provide basic data needed for future industrial production procedures. The calcium oxide method and a quaternary ammonium anion-exchange resin method were studied to separate organic acids as respective salts and the methanol-and-water method was studied to separate the water-insoluble pyrolytic lignin fraction. The calcium oxide and anion-exchange methods were shown to be effective in separation of organic acids, although further improvements would be needed. The pyrolytic lignin separation method was also shown to give lignin fraction that is effective for up to 40% replacement of phenol in the oriented strand board core-layer binder PF resins.
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Josephson-coupled superconducting regions embedded at the interfaces of highly oriented pyrolytic graphiteBallestar, Ana, Barzola-Quiquia, José, Scheike, Thomas, Esquinazi, Pablo 02 August 2022 (has links)
Transport properties of a few hundreds of nanometers thick (in
the graphene plane direction) lamellae of highly oriented pyrolytic graphite
(HOPG) have been investigated. Current–voltage characteristics as well as
the temperature dependence of the voltage at different fixed input currents
provide evidence for Josephson-coupled superconducting regions embedded in
the internal two-dimensional interfaces of HOPG, reaching zero resistance at low
enough temperatures.
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Synthesis and device applications of graphitic nanomaterialsUmair, Ahmad 01 December 2013 (has links)
This thesis is focused on two topics: (i) synthesis and characterization of bilayer graphene and pyrolytic carbon by atmospheric pressure chemical vapor deposition, and (ii) application of graphene in the fabrication of a buckyball memory device.
Monolayer and bilayer graphene are semi-metal with zero bandgap. One can induce a bandgap in bilayer graphene by applying a gate voltage in the stacking direction. Thus, bandgap and Fermi level in bilayer graphene can be controlled simultaneously with a double-gate device, making it a useful material for future semiconducting applications. Controlled synthesis of bilayer graphene would be the first step to fabricate bilayer graphene based devices. In this context, we report a uniform and low-defect synthesis of bilayer graphene on evaporated nickel films. Ultra-fast cooling is employed to control the number of layers and sample uniformity. The process is self-limiting, which leads to bilayer graphene synthesis over a wide range of growth-time and precursor flow-rate.
Pryolytic carbon is another important carbon nanomaterial, due to its diverse applications in electronic and biomedicalengineering. We employ chemical vapor deposition with ultra-fast cooling technique to synthesize pyrolytic carbon. Furthermore, we elucidate a method to calculate the in-plane crystal size by using Raman spectroscopy.
Finally, the use of bilayer graphene in a write-once read-many memory device has been demonstrated. The device showed irreversible switching from low-resistance to high-resistance state, with hysteresis in the transport characteristics. The control sample showed random switching and hysteresis due to electromigration of metal atoms into the active material of the device. We attribute the reliability and performance of the reported device to the ultra-smooth graphene contacts, which additionally inhibits electromigration from the underlying metallic film. Moreover, the memory device showed excellent endurance and retention characteristics.
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Utilização de um reator pirolítico retroalimentado (GEET) para melhoria da eficiência de um grupo motor gerador a gasolina / of a retrofitted pyrolytic reactor (GEET) to improve the efficiency of a gasoline generator setCarozzi , Helder José Costa 22 February 2017 (has links)
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Previous issue date: 2017-02-22 / This papers presents a new approach in terms of energy efficiency for the generation of electricity using a small Generator Motor Group (GMG), powered by internal combustion (fueled with water and gasoline), using pyrolytic reactor technology (GEET ), Aiming at the global reduction of consumption, temperature stability and improvement of the cooling, with consequent reduction of the cost of kW produced. In order to do so, the aim was to design and construct a pyrolytic reactor (GEET), based on available literature, as well as related scientific technical articles. This reactor, when in operation, obtains extra energy, necessary for the pyrolysis process, of the thermal energy produced by the combustion of the exhaust gases. This feature allows a mixture of water (fractured in hydrogen gas and oxygen gas) and gasoline to be used as fuel. To determine the efficiency of the GMG, working with the GEET, two well-defined experiments were performed. The first experiment was characterized by the operation and use of the GMG equipped with a new carburetor (factory original) and which, when in use, used only ordinary vehicular gasoline as fuel. The second experiment was characterized by the removal and replacement of the carburetor by the pyrolytic reactor (GEET), which allowed the use of water and gasoline (vehicular and aviation) as fuel, according to the proportions defined in the methodology. In both cases, temperature stability, electric charge behavior (fp = 1), fuel consumption (common gasoline and aviation) and, above all, the efficiency of the system were analyzed. It was possible to observe a certain thermal stability of the main structural block of the engine (block, head, head cover and spark plug), both in operation with the carbureted system (conventional) and with the GEET - Pantone system. Regarding the consumption, it was possible to verify that the GMG, when reaching the voltage near the nominal (115Vac), for the same type and value of load fed, the GEET device, applied was not efficient when using water and common gasoline for vehicular use , Resulting in an increase in fuel consumption, because in the process of mixing common gasoline with water (in the proportions defined by the methodology), this increased water inhibited the burning power of the anhydrous alcohol (dissolution) at the same time as There was no volatilization / atomization of the mixture, even with the return of the exhaust gases to the mixture reservoir (bubbling), which, at worst, could have caused an increase in the compression ratio, probably improving performance Of the set and reducing the operating temperature in the combustion chamber. However, when using the GEET-Pantone system with aviation gasoline, what it observed was a greater efficiency (%) for aviation gasoline in the proportion of 25/75 (twenty-five percent of aviation gasoline and seventy Five percent water, respectively), with an average yield of 8.46% versus 6.44% using GEET-Pantone only with aviation gasoline. The results obtained are not conclusive, yet, due to the relevance and innovation of the technological proposal, it justifies further studies of the subject. / Este trabalho apresenta, uma nova abordagem, em termos de eficiência energética, para a geração de eletricidade, utilizando um pequeno Grupo Motor Gerador – GMG, movido a combustão interna (alimentado com água e gasolina), a partir da tecnologia de reator pirolítico (GEET), visando à redução global de consumo, estabilidade de temperatura e melhoria do arrefecimento, com consequente redução do custo do kW produzido. Para isso, buscou-se dimensionar e construir um reator pirolítico (GEET), tendo como base, literatura disponíveis, além de artigos técnicos científicos relacionados. Este reator, quando em funcionamento, obtém energia extra, necessária ao processo de pirólise, da própria energia térmica decorrente da queima do combustível, proveniente dos gases de exaustão (escapamento). Tal característica permite que se utilize como combustível, uma mistura de água (fraturada em gás hidrogênio e gás oxigênio) e gasolina. Para determinar a eficiência do GMG, funcionando com o GEET, foi realizado dois experimentos bem definidos. O primeiro experimento se caracterizou pela operação e uso do GMG equipado com carburador novo (original de fábrica) e que, quando em funcionamento, utilizou somente gasolina veicular comum como combustível. O segundo experimento se caracterizou pela retirada e substituição do carburador pelo reator pirolítico (GEET), que permitiu, o uso de água e gasolina (veicular e de aviação) como combustíveis, conforme proporções definidas na metodologia. Nos dois casos, foram analisados a estabilidade da temperatura, o comportamento com carga elétrica (fp = 1), o consumo de combustível (gasolina comum e de aviação) e, principalmente, a eficiência do sistema. Foi possível observar, uma certa estabilidade térmica do principal bloco estrutural do motor (bloco, cabeçote, tampa do cabeçote e vela de ignição), tanto em funcionamento com o sistema carburado (convencional), quanto com o sistema GEET – Pantone. Quanto ao consumo, foi possível verificar que o GMG, ao atingir a tensão próxima da nominal (115Vca), para um mesmo tipo e valor de carga alimentada, o dispositivo GEET, aplicado não se mostrou eficiente quando utilizando água e gasolina comum de uso veicular, acarretando, inclusive, num aumento do consumo de combustível, pois no processo de mistura da gasolina comum com a água (nas proporções definidas pela metodologia), esta água acrescida, inibiu o poder de queima do álcool anidro (dissolução) ao mesmo tempo que não ocorreu uma volatização/atomização da mistura, mesmo com o retorno dos gases do escapamento para o reservatório da mistura (borbulhamento), o que, na pior das hipóteses, poderia ter provocado um aumento da taxa de compressão, melhorando, provavelmente, o desempenho do conjunto e reduzindo a temperatura de operação na câmara de combustão. Todavia, ao se utilizar o sistema GEET-Pantone com gasolina de aviação, o que observou, foi uma eficiência (%) maior para a gasolina de aviação numa proporção de 25/75 (vinte e cinco por cento de gasolina de aviação e setenta e cinco por cento de água, respectivamente), com rendimento médio de 8,46% contra 6,44% utilizando o GEET-Pantone somente com gasolina de aviação. Os resultados obtidos não são conclusivos, ainda, devido a relevância e inovação da proposta tecnológica, justifica estudos mais aprofundados da matéria.
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DETERMINAÇÃO DE HIDRAZINA POR VOLTAMETRIA DE ONDA QUADRADA SOBRE ELETRODO DE GRAFITE MODIFICADO COM FeTPyPz / HYDRAZINE DETERMINATION FOR VOLTAMMETRIC OF SQUARE SHAPED WAVE ON GRAPHITE ELECTRODE MODIFIED WITH FeTPyPzDantas, Luiza Maria Ferreira 22 August 2007 (has links)
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Previous issue date: 2007-08-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this work, the determination of hydrazine (N2H4) in aqueous solutions was investigated by
voltammetric techniques on pyrolytic graphite electrodes (GP) before and after modification with
iron tetra-pyridinoporphyrazine (FeTPyPz). The modified electrode GP/FeTPyPz presented
higher oxidation currents and better voltammetric profiles in comparison with the unmodified
electrodes. This modified electrode exhibited two reversible peaks attributed to the redox
processes: Fe(I)TPyPz/Fe(II)TPyPz and Fe(II)TPyPz/Fe(III)TPyPz. The pH optimization
conditions were performed in solutions prepared by the mixture of different proportions of 0.1
mol L-1 sodium hydroxide (NaOH) and 0.1 mol L-1 phosphate buffer solutions in order to obtain
solutions with pH varying from 7 to 13. In order to increase the sensitivity for hydrazine
oxidation, three voltammetric techniques were tested: cyclic voltammetry (CV), differential pulse
voltammetry (DPV) and square wave voltammetry (SWV). The best results were provided by the
latter one and the optimized conditions for hydrazine determinations were: i) electrolyte: 0,1 mol
L-1 NaOH solution; ii) frequency: 30 s-1; pulse amplitude: 50 mV and scan increment: 8 mV.
Under such conditions, the modified electrodes provided linear responses ranging from 5 up to
111 μmol L-1, with detection and quantification limits of 0.82 μmol L-1 and 2.7 μmol L-1,
respectively. The investigated sensor presented relative standard deviation values for repeatability
and reproducibility lower from 5%. The sensor was applied to analyze boiler water samples and a
recovery average of 116 % was found. / Neste trabalho, a determinação de hidrazina (N2H4) em solução aquosa
foi investigada com o uso de técnicas voltamétricas sobre eletrodos de grafite pirolítico
(GP), antes e após a modificação com tetrapiridinoporfirazina de ferro (FeTPyPz). O
eletrodo modificado GP/FeTPyPz apresentou correntes de oxidação da N2H4 mais
acentuadas e com melhor perfil voltamétrico em relação ao eletrodo não modificado.
Este eletrodo modificado apresentou dois picos reversíveis atribuídos aos processos redox:
Fe(I)TPyPz/Fe(II)TPyPz e Fe(II)TPyPz/Fe(III)TPyPz. As condições de otimização do
pH foram realizados em soluções preparadas através da mistura de diferentes proporções
de solução de hidróxido de sódio (NaOH) 0,1 mol Lfi1 e tampão fosfato (KH2PO4) 0,1 mol
Lfi1, a fim de obter soluções com pH variando de 7 a 13. Com o objetivo de aumentar a
sensibilidade para a oxidação de hidrazina, testou-se três técnicas voltamétricas: voltametria cíclica (CV), voltametria de pulso diferencial (DPV), e voltametria de onda quadrada
(SWV). Os melhores resultados foram obtitos através da técnica SWV e as condições
otimizadas para a determinação de hidrazina foram: i) eletrólito: solução NaOH 0,1 mol
Lfi1, ii) frequência de 30 sfi1, amplitude de pulso de 40 mV e incremento de varredura de
8 mV. Sob tais circunstâncias, o eletrodo modificado forneceu uma resposta linear entre 5
e 111 fimol Lfi1, com limite de detecção e quantificação de 0,82 fimol Lfi1 e 2,7 fimol Lfi1,
respectivamente. O sensor investigado apresentou valores de desvio padrão relativo para
estudos de repetibilidade da amostra e do sensor abaixo de 5%. O sensor foi aplicado em
amostras de águas de caldeira e apresentou média de recuperação de 116%.
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DETERMINAÇÃO DO HERBICIDA PARAQUAT SOBRE ELETRODOS DE GRAFITE PIROLÍTICO MODIFICADOS COM FTALOCIANINA DE COBALTO UTILIZANDO VOLTAMETRIA DE ONDA QUADRADA / DETERMINATION OF HERBICIDE PARAQUAT ON ELECTRODES OF PYROLYTIC GRAPHITE MODIFIED WITH COBALT PHTALOCYANINE USING WAVE SQUARE VOLTAMMETRYLopes, Ilanna Campelo 24 July 2006 (has links)
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Previous issue date: 2006-07-24 / Determination of paraquat (PQ) in watery solutions was investigated with the
technique of wave square voltammetry on pyrolytic graphite electrodes (PG) before
and after modifications with metal phtalocyanines. The electrode modified with cobalt
phthalocyanine (CoPc) presented PQ reduction currents more accented and
voltammetrics profiles better with respect to the electrodes unmodified and modified
with nickel phthalocyanine (NiPc), iron (FePc), manganese (MnPc) and in the acid
form (H2Pc). This sensor presented two reversible peaks for the reduction of PQ next
to - 0,71 V (peak 1) and - 1,10 V (peak 2) versus S C E. After optimization of cobalt
phthalocyanine concentration and the adsorption time on electrode, the best analysis
conditions for the PQ in 0,10 mol L-1 Britton-Robinson buffer solution (pH 7,0) was
established: frequency of 100 s-1, wave amplitude of 50 mV and scan increment of
2 mV. In these conditions, the modified electrode obtained a linear response range
from 5,00 x 10-7 to 2.91 x 10-5 mol L-1 (128,59 to 748,36 x 101 μg L-1) with detection
and quantification limits equals to 1,44 x 10-7 mol L-1 (37,03 μg L-1) and 4,79 x 10-7
mol L-1 (123,26 μg L-1)1, respectively. The studied sensor presented values below
5%, in terms of relative standard deviation, for repeatability (0,58% (± 0,27) for
N = 10) and reproducibility (1,58% (± 0,74) for N = 5) studies. The sensor was
applied in natural water samples and the gotten results was presented recovery
averages of 93,14% (± 7,16) and 119,25% (± 5,68) in two water samples analyzed. / A determinação de paraquat (PQ) em soluções aquosas foi investigada com a
técnica de voltametria de onda quadrada sobre eletrodos de grafite pirolítico (GP)
antes e após modificações com metaloftalocianinas. O eletrodo modificado com
ftalocianina de cobalto (CoPc) apresentou correntes de redução do PQ mais
acentuadas e melhores perfis voltamétricos em relação ao eletrodo não modificado e
modificados com ftalocianina de níquel (NiPc), de ferro (FePc), de manganês
(MnPc), e na forma ácida (H2Pc). Este sensor apresentou dois picos reversíveis para
redução do PQ em torno de - 0,71 V (pico 1) e - 1,10 V (pico 2) vs E C S. Após
otimizações da concentração da ftalocianina de cobalto e do tempo de adsorção no
eletrodo, as melhores condições de análise para o PQ em solução tampão Britton-
Robinson 0,10 mol L-1 (pH 7,0) estabelecidas foram: freqüência de 100 s-1, amplitude
de pulsos de 50 mV e incremento de varredura de 2 mV. Nestas condições, o
eletrodo modificado obteve uma resposta linear de 5,00 x 10-7 a 2,91 x 10-5 mol L-1
(128,59 a 748,36 x 101 μg L-1) com limites de detecção e quantificação iguais a
1,44 x 10-7 mol L-1 (37,03 μg L-1) e 4,79 x 10-7 mol L-1 (123,26 μg L-1),
respectivamente. O sensor estudado apresentou valores abaixo de 5%, em termos
de desvio padrão relativo, para estudos de repetibilidade (0,58% (± 0,27) para
N = 10) e reprodutibilidade (1,58% (± 0,74) para N = 5). O sensor foi aplicado em
amostras de águas naturais e os resultados obtidos apresentaram médias de
recuperação de 93,14% (± 7,16) e 119,25% (± 5,68) em duas amostras de água
analisadas.
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Pyrolysis Strategies for Effective Utilization of Lignocellulosic and Algal BiomassMaddi, Balakrishna January 2014 (has links)
No description available.
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Biotribological assessment for artificial synovial joints : the role of boundary lubricationGale, Lorne Raymond January 2007 (has links)
Biotribology, the study of lubrication, wear and friction within the body, has become a topic of high importance in recent times as we continue to encounter debilitating diseases and trauma that destroy function of the joints. A highly successful surgical procedure to replace the joint with an artificial equivalent alleviates dysfunction and pain. However, the wear of the bearing surfaces in prosthetic joints is a significant clinical problem and more patients are surviving longer than the life expectancy of the joint replacement. Revision surgery is associated with increased morbidity and mortality and has a far less successful outcome than primary joint replacement. As such, it is essential to ensure that everything possible is done to limit the rate of revision surgery. Past experience indicates that the survival rate of the implant will be influenced by many parameters, of primary importance, the material properties of the implant, the composition of the synovial fluid and the method of lubrication. In prosthetic joints, effective boundary lubrication is known to take place. The interaction of the boundary lubricant and the bearing material is of utmost importance. The identity of the vital active ingredient within synovial fluid (SF) to which we owe the near frictionless performance of our articulating joints has been the quest of researchers for many years. Once identified, tribo tests can determine what materials and more importantly what surfaces this fraction of SF can function most optimally with. Surface-Active Phospholipids (SAPL) have been implicated as the body’s natural load bearing lubricant. Studies in this thesis are the first to fully characterise the adsorbed SAPL detected on the surface of retrieved prostheses and the first to verify the presence of SAPL on knee prostheses. Rinsings from the bearing surfaces of both hip and knee prostheses removed from revision operations were analysed using High Performance Liquid Chromatography (HPLC) to determine the presence and profile of SAPL. Several common prosthetic materials along with a novel biomaterial were investigated to determine their tribological interaction with various SAPLs. A pin-on-flat tribometer was used to make comparative friction measurements between the various tribo-pairs. A novel material, Pyrolytic Carbon (PyC) was screened as a potential candidate as a load bearing prosthetic material. Friction measurements were also performed on explanted prostheses. SAPL was detected on all retrieved implant bearing surfaces. As a result of the study eight different species of phosphatidylcholines were identified. The relative concentrations of each species were also determined indicating that the unsaturated species are dominant. Initial tribo tests employed a saturated phosphatidylcholine (SPC) and the subsequent tests adopted the addition of the newly identified major constituents of SAPL, unsaturated phosphatidylcholine (USPC), as the test lubricant. All tribo tests showed a dramatic reduction in friction when synthetic SAPL was used as the lubricant under boundary lubrication conditions. Some tribopairs showed more of an affinity to SAPL than others. PyC performed superior to the other prosthetic materials. Friction measurements with explanted prostheses verified the presence and performance of SAPL. SAPL, in particular phosphatidylcholine, plays an essential role in the lubrication of prosthetic joints. Of particular interest was the ability of SAPLs to reduce friction and ultimately wear of the bearing materials. The identification and knowledge of the lubricating constituents of SF is invaluable for not only the future development of artificial joints but also in developing effective cures for several disease processes where lubrication may play a role. The tribological interaction of the various tribo-pairs and SAPL is extremely favourable in the context of reducing friction at the bearing interface. PyC is highly recommended as a future candidate material for use in load bearing prosthetic joints considering its impressive tribological performance.
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Caracterização e pirólise de arenitos asfálticos oriundos da Formação Pirambóia, Bacia do Paraná: avaliação da viabilidade para produção de óleo / Characterization and pyrolysis of asphaltic sandstones (tar sands) from Piramboia Formation, Paraná Basin: assessment of the feasibility for oil productionIris Medeiros Júnior 11 March 2015 (has links)
Neste trabalho, algumas caracterizações químicas foram realizadas em arenitos asfálticos da região de Piracicaba-SP, Formação Piramboia da Bacia do Paraná, para verificar seu potencial de produção de óleo. Para isso, as amostras obtidas da região foram submetidas a avaliação por termogravimetria, teor de umidade, teor de cinzas, teor de material orgânico por extração, pirólise, análise elementar e fracionamento em coluna. Por TGA observou-se que a 500 C praticamente todo material orgânico presente sofreu pirólise. A extração colaborou para se obter a classificação das amostras quanto ao teor de material orgânico, apresentando entre 4 e 13%, sendo que pelos teores encontrados a amostra AM06 é considerada de alto potencial produtivo, as amostras AM05, AM08 e AM09 são de médio, as amostras AM01, AM02, AM03 e AM07 possuem baixo, mas ainda atrativo, e a AM04 não possui atratividade. Pela avaliação elementar, a relação H/C e O/C dos extratos evidenciaram que algumas amostras estão no processo final da diagênese e outras no início da catagênese, indicando que elas estão no processo inicial de maturação. A avaliação cromatográfica dos extratos revelou que houve perdas de óleo por intemperismo restando majoritariamente compostos de alto peso molecular. O fracionamento permitiu verificar que as amostras AM01, AM06 e AM09 possuem maior quantidade de hidrocarbonetos livres e as amostras AM06 e AM07 e AM09 apresentaram maior teor de óleo. O procedimento de pirólise evidenciou que as amostras AM01, AM05, AM06 e AM09 apresentam maior potencial de geração de óleo, sendo que a faixa encontrada de óleo pirolítico ficou entre 2 e 8%, e através de avaliação por CGAR e CGAR-EM observou-se que ela promove a liberação de quantidades consideráveis de substâncias mais leves do que quando comparados aos extratos obtidos diretamente nas amostras originais. Além de produzir uma série homóloga de hidrocarbonetos parafínicos e olefínicos. A comparação dos produtos de pirólise dos arenitos com os produtos de pirólise de um resíduo de vácuo por CGAR-EM permitiu observar que existe similaridade entre suas composições, onde o processo de pirólise do resíduo de vácuo gera uma série homóloga de hidrocarbonetos entre C10 a C32, similar aos produtos de pirólise da amostra AM09, porém com menor variedade de tipos de hidrocarbonetos. A pré-avaliação da co-pirólise dos arenitos com resíduos plásticos indicou que é possível aumentar a geração de líquidos, porém é necessário mais estudo para afirmações inequívocas. Com base nos resultados das avaliações realizadas podemos concluir que a região apresenta na sua maioria potencial interessante para produção de óleo utilizando pirólise / In this work, some chemical characterizations were held on tar sands in the region of Piracicaba-SP, the South American Piramboia Formation from Paraná basin, to check its oil production potential. For this purpose, samples obtained in the region have undergone through evaluation by thermogravimetry, moisture content, ash content, content of organic material using extraction, pyrolysis process, elemental analysis and fractionation on open chromatography column. By TGA was noted that 500 C almost all-organic material present suffered pyrolysis. Extraction procedure collaborated to achieve the classification of samples regarding the content of organic material, from 4 to 13%, and by levels found at the sample AM06 is considered of high productive potential, the samples AM05, AM08 and AM09 have medium potential, the samples AM01, AM02, AM03 and AM07 have low potential, but still attractive, and the AM04 does not have any potential. By evaluating the atomic relationship between H/C and O/C of the extracts was possible to build up the Van Krevelen diagram and see that some samples are in the final process of diagenesis and other early catagenesis, indicating that they are in the early maturation process. Chromatographic evaluation of the extracts revealed that there were losses of oil by weathering process because it remains mostly high molecular weight compounds on the rocks. The fractionation has shown that samples AM01, AM06 and AM09 have higher free hydrocarbon amount and samples AM06, AM07 and AM09 presented a higher level of oil content. The pyrolysis procedure showed that the samples AM01, AM05, AM06 and AM09 presented greater oil generation potential, pyrolytic oil released from 2 to 8%, and through their evaluation by HRGC and HRGC-MS it was observed that it promotes the release of significant quantities of substances that are lighter than related to the extracts obtained directly in the original samples. In addition, it also promotes a production of homologous series of paraffinic and olefinic hydrocarbons. Comparison of pyrolysis products of sandstones with pyrolysis products of vacuum residue by HRGC-MS allowed to observe that there is similarity between their compositions, which pyrolysis process of vacuum residue generates a homologous series of hydrocarbons between C10 the C32, similar to AM09s pyrolysis products, however with minor variety of types of hydrocarbons. The pre-evaluation of co-pyrolysis of sandstones with plastic waste has indicated that it is possible to increase the liquid generation, but more study is needed for clear statements. Based on the results of the evaluations it can be concluded that the region has an interesting potential for producing oil using pyrolysis process
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Desenvolvimento de uma unidade pirol?tica com reator de cilindro rotativo: obten??o de bio-?leoFontes, L?cio ?ngelo de Oliveira 27 May 2011 (has links)
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Previous issue date: 2011-05-27 / The demand for alternative sources of energy drives the technological development so that many fuels and energy conversion processes before judged as inadequate or even non-viable, are now competing fuels and so-called traditional processes. Thus, biomass plays an important role and is considered one of the sources of renewable energy most important of our planet. Biomass accounts for 29.2% of all renewable energy sources. The share of biomass energy from Brazil in the OIE is 13.6%, well above the world average of participation. Various types of pyrolysis processes have been studied in recent years, highlighting the process of fast pyrolysis of biomass to obtain bio-oil. The continuous fast pyrolysis, the most investigated and improved are the fluidized bed and ablative, but is being studied and developed other types in order to obtain Bio-oil a better quality, higher productivity, lower energy consumption, increased stability and process reliability and lower production cost. The stability of the product bio-oil is fundamental to designing consumer devices such as burners, engines and turbines. This study was motivated to produce Bio-oil, through the conversion of plant biomass or the use of its industrial and agricultural waste, presenting an alternative proposal for thermochemical pyrolysis process, taking advantage of particle dynamics in the rotating bed that favors the right gas-solid contact and heat transfer and mass. The pyrolyser designed to operate in a continuous process, a feeder containing two stages, a divisive system of biomass integrated with a tab of coal fines and a system of condensing steam pyrolytic. The prototype has been tested with sawdust, using a complete experimental design on two levels to investigate the sensitivity of factors: the process temperature, gas flow drag and spin speed compared to the mass yield of bio-oil. The best result was obtained in the condition of 570 oC, 25 Hz and 200 cm3/min, temperature being the parameter of greatest significance. The mass balance of the elementary stages presented in the order of 20% and 37% liquid pyrolytic carbon. We determined the properties of liquid and solid products of pyrolysis as density, viscosity, pH, PCI, and the composition characterized by chemical analysis, revealing the composition and properties of a Bio-oil. / A demanda por fontes alternativas de energia impulsiona o desenvolvimento tecnol?gico de tal forma que muitos combust?veis e processos de convers?o energ?tica, antes julgada como inadequados ou mesmo invi?veis, s?o agora concorrentes de combust?veis e processos ditos tradicionais. Assim, a biomassa exerce um papel relevante, sendo considerada uma das fontes de energia renov?vel mais importante de nosso planeta. A biomassa contribui com 29,2 % de todas as fontes renov?veis de energia. A participa??o de energia de biomassa do Brasil na OIE ? de 13,6 %, sendo bem superior a m?dia mundial de participa??o. V?rios tipos de processos de pir?lise v?m sendo estudados nos ?ltimos anos, destacando-se o processo de pir?lise r?pida de biomassa para obten??o de Bio-?leo. Os processos cont?nuos de pir?lise r?pida, mais investigados e aprimorados s?o os de leito fluidizado e leito ablativo, entretanto vem sendo estudados e desenvolvidos outros tipos, visando obter um bio-?leo de melhor qualidade, com maior produtividade, menor consumo de energia, maior estabilidade e confiabilidade de processo e menor custo de produ??o. A estabilidade do produto Bio-?leo ? fundamental para a concep??o de dispositivos consumidores, tais como queimadores, motores de pist?o e turbinas. O presente estudo foi motivado para a produ??o de Bio-?leo, atrav?s da convers?o da biomassa vegetal ou do aproveitamento de seus res?duos industriais e agr?colas, sendo apresentada uma proposta alternativa de processo de pir?lise termoqu?mica, aproveitando a vantagem din?mica das part?culas no leito rotativo o que favorece a raz?o de contato g?s-s?lido e a transfer?ncia de calor e massa. O pirolisador foi projetado para operar em processo cont?nuo, contendo um alimentador de dois est?gios, um sistema desagregador da biomassa integrado com um separador de finos de carv?o e um sistema de condensa??o de vapores pirol?ticos. O Prot?tipo foi submetido a ensaios com serragem de madeira, utilizando um planejamento experimental completo em dois n?veis para investigar a sensibilidade dos fatores: temperatura do processo, fluxo de g?s de arraste e velocidade de centrifuga??o em rela??o ao rendimento m?ssico de Bio-?leo. O melhor resultado foi obtido na condi??o de 570 oC, 25 Hz e 200 cm3/min, sendo a temperatura o par?metro de maior signific?ncia. O balan?o
Tese de Doutorado PPGCEP/UFRN
L?cio ?ngelo de Oliveira Fontes vi
de massa elementar das fases apresentou da ordem de 20 % liquidos pirol?ticos e 37 % de carv?o. Foram determinadas as propriedades dos produtos l?quidos e s?lidos da pir?lise como densidade, viscosidade, pH, PCI, sendo a composi??o caracterizada atrav?s an?lise qu?mica, revelando as propriedades e composi??o de um Bio-?leo.
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