Dissertations / Theses: 'Flash point'

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Ingram, James Martyn. "Development of an explosimeter for the determination of residual fuel oil head space flammability hazards." Thesis, London South Bank University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336418.

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Ho, San-Ping. "Water spray suppression and intensification of high flash point hydrocarbon pool fires." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0829103-153046.

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Rowley, Jeffrey R. "Flammability Limits, Flash Points, and Their Consanguinity: Critical Analysis, Experimental Exploration, and Prediction." BYU ScholarsArchive, 2010. https://scholarsarchive.byu.edu/etd/2233.

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Accurate flash point and flammability limit data are needed to design safe chemical processes. Unfortunately, improper data storage and reporting policies that disregard the temperature dependence of the flammability limit and the fundamental relationship between the flash point and the lower flammability limit have resulted in compilations filled with erroneous values. To establish a database of consistent flammability data, critical analysis of reported data, experimental investigation of the temperature dependence of the lower flammability limit, and theoretical and empirical exploration of the relationship between flash points and temperature limits are undertaken. Lower flammability limit measurements in a 12-L ASHRAE style apparatus were performed at temperatures between 300 K and 500 K. Analysis of these measurements showed that the adiabatic flame temperature at the lower flammability limit is not constant as previously thought, rather decreases with increasing temperature. Consequently the well-known modified Burgess-Wheeler law underestimates the effect of initial temperature on the lower flammability limit. Flash point and lower temperature limit measurements indicate that the flash point is greater than the lower temperature limit, the difference increasing with increasing lower temperature limit. Flash point values determined in a Pensky-Martens apparatus typically exceed values determined using a small-scale apparatus above 350 K. Data stored in the DIPPR® 801 database and more than 3600 points found in the literature were critically reviewed and the most probable value recommended, creating a database of consistent flammability data. This dataset was then used to develop a method of estimating the lower flammability limit, including dependence on initial temperature, and the upper flammability limit. Three methods of estimating the flash point, with one based entirely on structural contributions, were also developed. The proposed lower flammability limit and flash point methods appear to predict close to, if not within, experimental error.

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Carrion, Domenech Luis Enrique. "Study of high flash point ethyl alcohol-based secondary fluids applied in Ground Source Heat Pumps systems." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-260335.

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Ethyl alcohol (ethanol) as secondary fluids is very popular as heat transfer fluid for indirect refrigeration system with ground source heat pump systems (GSHP) in several countries such as Sweden, Norway, Switzerland, Finland and other European countries. There have been several researches about the future ofthe refrigeration sector, refrigerants and refrigeration systems. Moreover, strict regulations such as F-gasregulation and Kigali Amendment forcing a phase down of many current widely used high global warming potential (GWP) refrigerants, i.e. R134a or R410A. Therefore, secondary refrigeration systems and their working fluids are expected to play a key role in order to minimize the refrigerant charge in the systems, reduce the indirect refrigerant leakages as well as increase the safety during operation. The aim of this thesis is to investigate the effect different additives to increase the flame point together with ethanol-based secondary fluids and validate their thermophysical properties by comparing them with reference values for pure ethanol water solutions. The study aims to design a new commercial ethyl alcohol-based product for GSHP system that could replace existing ones in the Swedish market and could workwith natural or flammable low GWP refrigerants. Different high flash point additives were tested such as 1-propyl alcohol, n-butyl alcohol, glycerol andpropylene carbonate. Thermophysical properties were investigated and a GSHP model in Excel was created in order to assess the energy performance of the resulted blends. After screening different blends and assessing the energy performance, glycerol as additive in low concentration seems to be the future for the ethyl alcohol-based secondary fluids because of its high flashpoint (160ºC) that will reduce the flammability risk associated to ethyl alcohol blends, the low viscosity (by 12% lower compared to pure ethyl alcohol blends) that help reduce pumping power by 4.5% compared topure ethyl alcohol blends. Moreover, ethyl alcohol and glycerol blend showed the lost in heat transfer coefficient by 4% lower compared to pure ethyl alcohol blends due to lower thermal conductivity compared to pure ethyl alcohol blends. Finally, it is a rather cheap and natural product which has no problem related to corrosion since ethyl alcohol and glycerol are less corrosive than water. Although, flash point test was not conducted so there is no data regarding the flash point, it is expected the flash point is increased due to the high flash point of glycerol compared to ethyl alcohol or other possible additives. Therefore, it is expected that the flammability risk associated to ethyl alcohol-based secondary fluids is reduced.
Etylalkohol (etanol) som köldbärare är mycket populärt som värmeöverföringsvätska för indirekt kylsystemmed bergvärmepumpsystem (BVP) i Sverige, Norge, Schweiz, Finland och andra europeiska länder. Fleraundersökningar har gjorts om kylsektorns framtid, köldmedier och kylsystem. Dessutom strängaförordningar som F-gas förordning och Kigali- förordning tvingar en utfasning av många nuvarande allmäntanvända köldmedier med den höga globala uppvärmningspotentialen (GWP), dvs. R134a eller R410A. Därför förväntas det att kylsystem och deras köldbärare spela en nyckelroll för att minimera köldmediumsmängd i systemen, minska de indirekta köldmedieläckage och öka säkerheten under drift. Syftet med detta examensarbete är att undersöka effekten av olika tillsatser för att öka flammanpunkten tillsammans med etanolbaserade köldbärare och validera deras termofysikaliska egenskaper genom att jämföra dem med referensvärden för rena etanolvattenlösningar. Studien syftar till att utforma en nykommersiell etylalkoholbaserad produkt för BVP-system som skulle kunna ersätta befintliga produkter på den svenska marknaden och kan arbeta med naturliga eller brandfarliga köldmedier med låg GWP. Olika tillsatser med hög flampunkt testades såsom 1-propylalkohol, n-butylalkohol, glycerol och propylenkarbonat. Termofysikaliska egenskaper undersöktes och en BVP-modell i Excel skapades för att bedöma energiprestanda för olika blandningarna. De erhållna resultaten för olika blandningar visar att glycerol i en låg koncentration som tillsats kan vara framtidens additiv för de etylalkoholbaserade köldbärare på grund av dess höga flampunkt (160 ºC) som förmodligen kan minska brandrisken för etylalkoholblandningar. Dessutom hade glycerol och etanolblandningar den lägsta viskositeten (c.a.12% lägre jämfört med ren etylalkoholblandningar) som bidrar tillen minskning av pumpeffekten med c.a. 4,5% jämfört med rena etylalkoholblandningar. Däremot visade etylalkohol och glycerol blandningen c.a. 4% lägre värmeöverövergångstal jämfört med de rena etylalkoholblandningar på grund av lägre värmeledningsförmåga jämfört med ren etylalkoholblandningar. Slutligen är glycerol en ganska billig och naturlig produkt som inte har några korrosionsproblem eftersom etylalkohol och glycerol är mindre frätande än vatten. Även om flampunkttest inte genomfördes i projektet, förväntas det att flampunkten ökas lite på grund av den höga flampunkten av glycerol jämfört med etylalkohol och andra tillsatser. Därför förväntas det att brännbarhetsrisken förknippad med etylalkoholbaserade köldbärare reduceras.

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Carareto, Natalia Daniele Dorighello 1984. "Solid-liquid equilibrium and flash point of fatty mixtures = Equilíbrio sólido-líquido e ponto de fulgor de misturas graxas." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255155.

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Orientadores: Antonio José de Almeida Meirelles, Mariana Conceição da Costa, Jérôme Pauly
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O estudo das propriedades físico-químicas de materiais graxos é uma demanda mundial crescente, principalmente devido ao incentivo do seu uso como fonte de energia e para a alimentação. Faz-se importante estudar e compreender todas as condições de equilíbrio que podem ser observadas durante o processamento de compostos graxos, por exemplo, óleos vegetais e biodieseis, desde a sua extração, refino e estocagem. Dados de equilíbrio sólido-líquido podem ser usados para melhorar ou propor novos processos de separação. Já o ponto de fulgor é uma propriedade importante que deve ser observada no armazenamento, transporte e produção de compostos inflamáveis, como o biodiesel. Este trabalho teve como objetivos estudar o equilíbrio sólido-líquido de misturas binárias graxas formadas por álcoois graxos, ésteres graxos ou ácidos graxos, e avaliar o ponto de fulgor de misturas de ésteres etílicos, que são constituintes principais de biodieseis, e etanol, presente em teores residuais. Os pontos de fulgor de ésteres etílicos, e também de misturas binárias destes ésteres com etanol foram determinados experimentalmente e a partir dos resultados foi proposto um modelo empírico para a predição do ponto de fulgor de biodieseis em função da sua composição e teor de etanol. Os diagramas de equilíbrio sólido-líquido de sistemas binários formados por ácidos + álcoois graxos ou formados por álcoois + álcoois graxos foram determinados experimentalmente através de calorimetria exploratória diferencial (DSC) com a intenção de melhor compreender as reações eutética, peritética e metatética que aparecem nos diagramas de equilíbrio tanto com taxas de aquecimento linear ou via o uso da ferramenta de stepscan DSC. Para complementar o estudo foram usadas técnicas de difração de Raios-X e microscopia óptica com controle de temperatura. O efeito da pressão sobre o equilíbrio sólido-líquido foi avaliado para misturas binárias de ésteres etílicos ou de álcoois graxos utilizando-se microscopia ótica acoplada a um aparato experimental que permite o aumento da pressão até 80 MPa. Foram utilizados os modelos termodinâmicos para coeficiente de atividade Margules 2 e 3-sufixos e NRTL para descrever a linha liquidus dos sistemas que apresentaram ponto peritético, e um modelo termodinâmico preditivo foi aplicado para modelar o ESL em função da pressão e, em ambos os casos, obteve-se um ajuste satisfatório em comparação aos dados experimentais
Abstract: The study on the physicochemical properties of fatty materials has acquired a growing importance, mainly due to the incentive of their use in energy and nutrition. The efficient production and use of fatty compounds requires a good knowledge of their properties and phase behavior that are necessary for development of processes, especially in production steps such as extraction and refining, but also during storage of the final products. Solid-liquid equilibrium data can be used to improve or propose new separation processes. Also the flash point is an important property that must be considered during storage, transportation and production of flammable compounds, such as biodiesel. This work aimed to study the solid-liquid equilibrium of binary mixtures consisting of fatty alcohols, fatty esters or fatty acids, and to evaluate the flash point of mixtures of ethyl esters, the major constituents of biodiesels, and ethanol, also present in biodiesel in residual levels. Flash points of ethyl esters, and also of the binary mixtures of ethyl esters with ethanol were determined experimentally. An empirical model for predicting the flash point of biodiesels as a function of composition and ethanol content was proposed. The solid-liquid phase diagrams of binary mixtures of fatty alcohol + fatty alcohol or fatty alcohols + fatty acid were determined experimentally by differential scanning calorimetry (DSC), using a linear heating rate, or by a stepscan DSC method, with the aim of investigating the occurrence of the eutectic, peritectic and metatectic reactions. X-ray diffraction and optical microscopy with temperature control techniques were applied to complement the understanding of the phase diagrams. The effect of pressure on the solid-liquid equilibrium was investigated for the binary mixtures of ethyl esters or fatty alcohols using an optical microscope coupled to a high pressure cell which allows the pressure increase up to 80 MPa. Margules 2 and 3-suffix and NRTL thermodynamic models were used for describing the liquidus line of the systems that presented peritectic point, and a predictive thermodynamic model was used to model the ESL function of pressure, which in both cases, gave a satisfactory fit compared to the experimental data
Doutorado
Engenharia de Alimentos
Doutora em Engenharia de Alimentos

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Mattos, Rodrigo Alves de 1979. "Estudo da influência de aditivos naturais nos pontos de entupimento a frio, de turbidez e de fulgor de biodiesel e de misturas diesel-biodiesel." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248843.

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Orientador: Matthieu Tubino
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: O presente trabalho foi realizado usando biodieseis preparados a partir de óleos de soja, canola, milho, girassol e, também, de gordura suína, através de reações transesterificação. Para todos esses biodieseis foram determinados o ponto de entupimento a frio, o ponto de fulgor e o perfil cromatográfico. Estes biodieseis foram misturados com diesel de petróleo para se produzir misturas contendo 5% do biocombustível (B5), 10% (B10) e 20% (B20), e os ensaios citados foram realizados nestas amostras. Visando a diminuição do ponto de entupimento a frio, alguns aditivos naturais foram testados e se mostraram eficientes. Por exemplo, o limoneno reduziu o ponto de entupimento do biodiesel de óleo soja em mais de 7°C. No biodiesel de gordura suína a redução foi de 10°C, o que significa o ponto de entupimento a frio em temperatura inferior a 13°C. Os aditivos utilizados são solúveis nos biodieseis estudados e, também, nas misturas diesel-biodiesel, pelo menos nas concentrações testadas. Como importante exemplo de abaixamento do ponto de entupimento a frio das misturas diesel-biodiesel de gordura suína com 10% de biodiesel (B10), podese citar o caso da terebentina que provocou uma redução de aproximadamente 8°C (de 12,7ºC para 5,0°C). Este mesmo aditivo caus ou uma redução de 13,6 ºC (de 20,3ºC para 6,7ºC), na mistura diesel-biodiesel de gordura suína com 20% de biodiesel (B20). Este resultado é muito significativo por implicar na possibilidade de usar este tipo de combustível mesmo em regiões mais ao sul do país durante o inverno
Abstract: The present studies were performed preparing biodiesel from soya, canola, corn, sunflower oils and the fat swine, through transesterification reaction. The biodiesel produced from these oils were studied for: cold filter plugging point, flash point and for chromatographic analysis. The biodiesels were mixed with diesel to produce blends containing 5% of the biofuel (B5), 10% (B10) and 20% (B20), and these samples were also analyzed by the same techniques as discussed earlier. In order to decrease the cold filter plugging point, some natural additives have been tested and were proved effectively. For example, limonene caused more than 7°C reduction in the cold filter plugging point of soybean biodiesel. In the biodiesel obtained from the swine fats, the reduction was found around 10°C and less than 13°C for the cold filter plugging point. The additives are soluble in studied biodiesels and also in the dieselbiodiesel blends, at least, in the concentrations tested. One of the important example of the reduction in the cold filter plugging point of diesel-biodiesel blends of swine fats with 10% biodiesel (B10), using turpentine as additive which caused reduction of approximately 8°C (from 12,7ºC up to 5,0°C). The same additive caused a reduction of 13,6 ºC (from 20.3 ºC up to 6.7 °C) in the cold filter plugging point of diesel -biodiesel blends of swine fats with 20% biodiesel (B20). This result is very significant because it is possible to use this type of fuel in south regions of the country during the winter
Doutorado
Quimica Analitica
Doutor em Ciências

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Balingit, JoAnn Alegre. "Internet plagiarism as flash point and folklore / do high school students plagiarize more from Internet sources than from print-based sources?" Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 144 p, 2008. http://proquest.umi.com/pqdweb?did=1654487881&sid=3&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Dorighello, Carareto Natalia Daniele. "Equilibre solide-liquide et point d'éclair de mélanges de corps gras." Thesis, Pau, 2014. http://www.theses.fr/2014PAUU3048.

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L’étude des propriétés physico-chimiques des matières grasses constitue une demande mondiale croissante liée à l’augmentation constante de leur utilisation comme source d'énergie et pour l'alimentation. Une bonne connaissance de leurs propriétés thermophysiques et de leur comportement de phases est nécessaire pour la production, l'utilisation efficace de ces matières grasses et le développement des processus d'extraction au niveau du raffinage et du stockage. Des données d'équilibre solide-liquide peuvent être utilisées pour améliorer les procédés existants, et également pour le développement des nouveaux procédés de séparation. Ainsi, le point d'éclair est une propriété importante qui doit être observée pendant le stockage, le transport et la production de composés inflammables, tels que le biodiesel. Ce travail vise à étudier l'équilibre solide-liquide de mélanges binaires constitués d'alcools gras, d’acides gras et d’esters éthyliques. Il porte aussi sur l'évaluation du point d’éclair de mélanges d'esters éthyliques, constituants majoritaires du biodiesel, et de l'éthanol, présent à des niveaux résiduels dans le biodiesel. Les points d’éclair des esters éthyliques mais également des mélanges binaires d'esters éthyliques et d’éthanol, ont été déterminés expérimentalement. Un modèle empirique de prédiction des points d’éclair des biodiesels en fonction de leur composition et de leur teneur en éthanol a été proposé. Les diagrammes de phases solide-liquide des mélanges binaires d'alcool gras + alcool gras ou d’alcools gras + acide gras ont été déterminés expérimentalement par analyse calorimétrique différentielle (DSC). Cette étude permet de caractériser les réactions eutectique, péritectique et métatectique, en utilisant une vitesse de chauffe linéaire ou une méthode de Stepscan DSC. Des mesures de diffraction rayons X et de microscopie optique de contrôle de la température ont été appliquées pour compléter la compréhension des diagrammes de phases. L'effet de la pression sur l'équilibre solide-liquide a aussi été mesuré pour les mélanges binaires d’esters éthyliques ou d'alcools gras en utilisant un microscope optique couplé à une cellule à haute pression qui permet d’augmenter la pression jusqu'à 80 MPa sur une large gamme de température. Les modèles thermodynamiques Margules 2 et 3-suffix et NRTL ont été utilisés pour décrire la ligne du liquidus des systèmes présentant un point péritectique, alors qu’un modèle thermodynamique prédictif a permis de modéliser l'ESL en fonction de la pression. Dans les deux cas, on a observé un ajustement satisfaisant par rapport aux données expérimentales
The study on the physicochemical properties of fatty materials has acquired a growing importance, mainly due to the incentive of their use in energy and nutrition. The efficient production and use of fatty compounds requires a good knowledge of their properties and phase behavior that are necessary for development of processes, especially in production steps such as extraction and refining, but also during storage of the final products. Solid-liquid equilibrium data can be used to improve or propose new separation processes. Also the flash point is an important property that must be considered during storage, transportation and production of flammable compounds, such as biodiesel. This work aimed to study the solid-liquid equilibrium of binary mixtures consisting of fatty alcohols, fatty esters or fatty acids, and to evaluate the flash point of mixtures of ethyl esters, the major constituents of biodiesels, and ethanol, also present in biodiesel in residual levels. Flash points of ethyl esters, and also of the binary mixtures of ethyl esters with ethanol were determined experimentally. An empirical model for predicting the flash point of biodiesels as a function of composition and ethanol content was proposed. The solid-liquid phase diagrams of binary mixtures of fatty alcohol + fatty alcohol or fatty alcohols + fatty acid were determined experimentally by differential scanning calorimetry (DSC), using a linear heating rate, or by a stepscan DSC method, with the aim of investigating the occurrence of the eutectic, peritectic and metatectic reactions. X-ray diffraction and optical microscopy with temperature control techniques were applied to complement the understanding of the phase diagrams. The effect of pressure on the solid-liquid equilibrium was investigated for the binary mixtures of ethyl esters or fatty alcohols using an optical microscope coupled to a high pressure cell which allows the pressure increase up to 80 MPa. Margules 2 and 3-suffix and NRTL thermodynamic models were used for describing the liquidus line of the systems that presented peritectic point, and a predictive thermodynamic model was used to model the ESL function of pressure, which in both cases, gave a satisfactory fit compared to the experimental data

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Fregolente, Lernardo Vasconcelos 1980. "Aplicação de planejamento de experimentos em diferentes etapas do refino de petroleo." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266397.

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Orientador: Maria Regina Wolf Maciel
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: Neste trabalho, a técnica de planejamento de experimentos foi aplicada em diferentes estudos de otimização realizados na Refinaria de Paulínia (Replan). O trabalho abrange aplicações da técnica em escala laboratorial, em ferramenta computacional, até a utilização da técnica em diferentes plantas industriais. Os estudos de laboratórios consistiram na avaliação da dependência da lubricidade do diesel metropolitano em relação à sua composição e no desenvolvimento de uma nova metodologia para determinação do ponto de fulgor de frações leves de petróleo. Através de planejamentos fatoriais aplicados a um simulador do processo de coqueamento retardado (denominado DC-SIM), foram geradas equações polinomiais simples para a previsão de rendimentos dos produtos da unidade em sua etapa reacional. Utilizando estas equações, curvas de nível foram obtidas, as quais auxiliam na análise do comportamento da unidade frente a modificações nas condições de operação. Duas aplicações consistiram na realização de testes em plantas industriais. Primeiramente, utilizando planejamentos em dois níveis, foram levantados novos modelos para o controle avançado de uma torre de fracionamento de naftas através da realização de testes de identificação utilizando perturbações em degrau. A metodologia de planejamento de experimentos possibilitou uma análise multivariável do sistema. Finalmente, foram realizados experimentos seguindo planejamentos com configuração estrela para a maximização da recuperação de moléculas na faixa de destilação do GLP nas áreas de fracionamento de gases das duas unidades de coqueamento retardado da Replan. Por se tratar da maior refinaria de petróleo do país, sendo responsável por cerca de 20% da capacidade de refino no Brasil, a utilização de planejamentos fatoriais foi de fundamental importância para a viabilização de alguns testes em planta, já que reduz significativamente o número de experimentos necessários quando comparada à metodologia de avaliação de um fator por vez. Desta forma, o impacto dos testes na produção de derivados foi minimizado. Além disso, os resultados obtidos propiciaram um ganho econômico expressivo para a refinaria.
Abstract: In this work, experimental design technique was applied to different optimization studies, which were carried out in the Paulínia Refinery (Replan). The work covers applications of the technique in laboratorial scale, in computational tool, and the use of the technique in different industrial plants. The laboratory studies consisted in the evaluation of the dependence of the metropolitan diesel oil lubricity in relation to its composition and in the development of a new methodology to determine the flash point of light fractions of petroleum. Through factorial designs applied to a delayed coke simulator (named DC-SIM), simple polynomial equations were generated to predict the products yields of the unit in the reaction step. Using these equations, contour plots were obtained, which helped the analysis of the process response due to changes in the operating conditions. Two applications were done in industrial plants. First, using two level factorial designs, new models were adjusted to be used in the advanced control of a naphtha fractionation tower. The identification tests were carried out giving step disturbance in the manipulated variables. The experimental design methodology allowed a multivariable analysis of the system. Finally, experiments were done according to star configuration factorial designs in order to maximize the recovery of LPG molecules in the gases fractionating units of two delayed coke plants of Replan. Since Replan is the biggest oil refinery in Brazil, responsible for 20% of the national refining capacity, the use of factorial designs had a fundamental importance to allow the running of some tests in the plant. It reduces significantly the number of experiments, when it is compared to univariate methodology. Therefore, the impact of the tests in the production was minimized. Furthermore, the results provided very expressive financial earns
Doutorado
Desenvolvimento de Processos Químicos
Doutor em Engenharia Química

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Silveira, Eva Lúcia Cardoso 1981. "Desenvolvimento de novas propostas para análise de bioesel e estudo da relação entre ponto de fulgor e o teor de álcool reiduol." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248838.

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Orientador: Matthieu Tubino
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: Um método de baixo custo é proposto neste trabalho para a análise quantitativa do álcool residual em biodiesel através da determinação do ponto de fulgor. Foram analisados ésteres metílicos obtidos de óleos de soja, milho, girassol e de sebo bovino. Os ésteres etílicos foram obtidos de óleo de soja. Em todos os casos ficou evidente que há uma correlação entre o ponto de fulgor e o teor de álcool residual no biodiesel. Assim, o parâmetro ponto de fulgor pode ser usado diretamente para determinar o teor de álcool residual do biodiesel. Foi proposto também um método para a determinação de fósforo em biodiesel por espectrofotometria de absorção molecular UV-Vis. As amostras de biodiesel são mineralizadas por calcinação a 550 °C seguindo dissolução do resíduo em H2SO4 1,0 mol L. O procedimento analítico é baseado na formação do complexo azul de molibdênio. Empregou-se o ácido 1-amino-2-naftol-4-sulfônico como agente redutor. O método foi aplicado para amostras de biodiesel de soja, canola, girassol e de sebo bovino. Os limites de detecção e quantificação obtidos para fósforo foram de 0,57 mg kg e 1,71 mg kg, respectivamente. O desvio padrão relativo médio obtido foi cerca de 5 %. A simplicidade do procedimento adicionado à precisão, exatidão e o baixo custo indicam que é uma excelente opção para a determinação de fósforo em biodiesel. Um terceiro método, neste caso, para a determinação de ânions em biodiesel baseado na extração com água assistida por ultrassom também foi desenvolvido neste trabalho. Os extratos obtidos das amostras de biodiesel foram analisados por cromatografia de íons. Os limites de quantificação foram 0,97; 4,10; 0,30; 2,47 e 0,26 mg kg para acetato, formiato, cloreto, fosfato e sulfato, respectivamente. A técnica de cromatografia de íons mostrou-se viável para a separação e quantificação de ânions orgânicos e inorgânicos em biodiesel simultaneamente diminuindo assim o tempo de análise
Abstract: A low cost method is proposed in this work for the quantitative analysis of residual alcohol in biodiesel through determination of the flash point. We analyzed methyl esters obtained from oils such as soy, corn, sunflower and of bovine fat. The ethyl esters were obtained from soy oil. In all cases it became very evident that there is a correlation between the flash point and the residual alcohol content in the biodiesel. Therefore the parameter flash point can be used to directly determine the residual alcohol content of biodiesel. A method has been proposed for the determination of phosphorus in biodiesel by UV-vis molecular absorption spectrophotometry. The biodiesel samples are mineralized using an ashing procedure at 550 °C following dissolution of the residue in 1.0 mol L H2SO4. The analytical procedure is based on the formation of a blue molybdenum complex. 1-amino-2naphthol-4-sulfonic acid is used as reducing agent. The method was applied to biodiesel samples of soy, canola and sunflower oils and of bovine fat. The limits of detection and quantification are 0.57 mg kg and 1.71 mg kg, respectively. The average standard deviation obtained was about 5 %. The simplicity of the procedure added to its precision, accuracy and low cost indicate that it is an excellent option for the determination of phosphorus in biodiesel. A third method, in this case, for the determination of anions in biodiesel based on extraction with ultrasound assisted water has also been developed in this study. The extracts of biodiesel samples were analyzed by ion chromatography. The limits of quantification obtained were 0.97, 4.10, 0.30, 2.47 and 0.26 mg kg for acetate, formate, chloride, phosphate and sulfate, respectively. The technique of ion chromatography proved to be feasible for the simultaneously separation and quantification of organic anions in biodiesel, thereby reducing analysis time
Doutorado
Quimica Analitica
Doutora em Ciências

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11

Gao, Hantian. "Nanoscale Characterization and Control of Native Point Defects in Metal Oxide Semiconductors and Device Structures." The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1618838504594148.

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Mazoyer, Pascale. "Analyse et caractérisation des mécanismes de perte de charge relatifs aux diélectriques multicouches du point mémoire EPROM." Université Joseph Fourier (Grenoble), 1994. http://www.theses.fr/1994GRE10009.

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L'evolution des memoires a semiconducteurs et en particulier de la famille eprom (erasable read only memory) est liee a l'identification des phenomenes determinants du processus de perte de la charge electronique stockee. Les cellules etudiees ici sont toutes proches des points de fonctionnement de filieres industrialisees ou en cours de developpement (de 4 a 256 megabits). On distingue deux mecanismes de perte de charge. Le premier est une fonction de la nature des dielectriques presents dans la structure et des lois qui regissent la conduction qui leur est associee. Le second est lie a la migration des ions alcalins dans la cellule. Partant de l'analyse des proprietes de la tricouche ono (oxyde nitrure oxyde) et en emettant l'hypothese de l'injection d'electrons en fin d'ecriture, un modele de perte de charge est propose. Il est base sur l'emission electronique assistee en temperature et la migration des electrons a travers l'ono. Les mesures de perte de charge montrent qu'il ne faut pas descendre, dans la realisation de l'ono, en deca de l'epaisseur tunnel de chaque couche et que l'obtention de couche d'epaisseur homogene et stchiometrique ameliore la fiabilite du dispositif. Cette analyse conduit, de meme, a la proposition d'un dielectrique adapte aux applications tres avancees. Forme par l'association de nitrure et d'oxyde, le no apparait comme un candidat interessant les generations eprom et flash eprom 256 mb. L'etude des contaminants ioniques a mis en uvre la methode tvs, qui s'avere un outil puissant, permettant l'evaluation rapide et precise de la densite d'ions mobile dans les dielectriques epais. Une solution economiquement viable a ete mise au point pour prevenir les effets d'une eventuelle contamination sur le plan memoire. Il s'agit de la juxtaposition judicieuse d'un verre au phosphore et d'un verre au bore et au phosphore

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Krištofík, František. "Stabilita aprotických elektrolytů v lithno-iontových akumulátorech." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220955.

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The Master thesis describe basic electrochemical processes in lithium-ion batteries and characteristic organic polar solvents for these articles. It focuses primarily on the aprotic liquid electrolytes for lithium-ion batteries and the subsequent use of gas chromatography to analyze the collected gas sample from the test article. For this experiment is, in this Master thesis, designed and described experimental arrangement in the form of a glass cell, which allows collection from the space above the working electrode. Finally, the work evaluates the effect of electrode potential on the stability of electrolytes in strongly positive potentials.

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Josyula, Sai Prashanth. "On the Applicability of a Cache Side-Channel Attack on ECDSA Signatures : The Flush+Reload attack on the point multiplication in ECDSA signature generation process." Thesis, Blekinge Tekniska Högskola, Institutionen för datalogi och datorsystemteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-10820.

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Context. Digital counterparts of handwritten signatures are known as Digital Signatures. The Elliptic Curve Digital Signature Algorithm (ECDSA) is an Elliptic Curve Cryptography (ECC) primitive, which is used for generating and verifying digital signatures. The attacks that target an implementation of a cryptosystem are known as side-channel attacks. The Flush+Reload attack is a cache side-channel attack that relies on cache hits/misses to recover secret information from the target program execution. In elliptic curve cryptosystems, side-channel attacks are particularly targeted towards the point multiplication step. The Gallant-Lambert-Vanstone (GLV) method for point multiplication is a special method that speeds up the computation for elliptic curves with certain properties. Objectives. In this study, we investigate the applicability of the Flush+Reload attack on ECDSA signatures that employ the GLV method to protect point multiplication. Methods. We demonstrate the attack through an experiment using the curve secp256k1. We perform a pair of experiments to estimate both the applicability and the detection rate of the attack in capturing side-channel information. Results. Through our attack, we capture side-channel information about the decomposed GLV scalars. Conclusions. Based on an analysis of the results, we conclude that for certain implementation choices, the Flush+Reload attack is applicable on ECDSA signature generation process that employs the GLV method. The practitioner should be aware of the implementation choices which introduce vulnerabilities, and avoid the usage of such ECDSA implementations.

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Doležal, Filip. "Administrativní objekt - Brno,Medlánky." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-371890.

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The purpose of this diploma thesis is the processing of the project documentation of an office building. The structure is designed as a detached building with five floors and with one basement. A garage for 10 cars is situated in the basement and there is office space located on the floors. The structural system of the building is reinforced concrete skeleton. Exterior building envelope si made of glazed curtain wall. The roof of the building is flat.

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Ayvazyan, Vigen. "Etude de champs de température séparables avec une double décomposition en valeurs singulières : quelques applications à la caractérisation des propriétés thermophysiques des matérieux et au contrôle non destructif." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14671/document.

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La thermographie infrarouge est une méthode largement employée pour la caractérisation des propriétés thermophysiques des matériaux. L’avènement des diodes laser pratiques, peu onéreuses et aux multiples caractéristiques, étendent les possibilités métrologiques des caméras infrarouges et mettent à disposition un ensemble de nouveaux outils puissants pour la caractérisation thermique et le contrôle non desturctif. Cependant, un lot de nouvelles difficultés doit être surmonté, comme le traitement d’une grande quantité de données bruitées et la faible sensibilité de ces données aux paramètres recherchés. Cela oblige de revisiter les méthodes de traitement du signal existantes, d’adopter de nouveaux outils mathématiques sophistiqués pour la compression de données et le traitement d’informations pertinentes. Les nouvelles stratégies consistent à utiliser des transformations orthogonales du signal comme outils de compression préalable de données, de réduction et maîtrise du bruit de mesure. L’analyse de sensibilité, basée sur l’étude locale des corrélations entre les dérivées partielles du signal expérimental, complète ces nouvelles approches. L'analogie avec la théorie dans l'espace de Fourier a permis d'apporter de nouveaux éléments de réponse pour mieux cerner la «physique» des approches modales.La réponse au point source impulsionnel a été revisitée de manière numérique et expérimentale. En utilisant la séparabilité des champs de température nous avons proposé une nouvelle méthode d'inversion basée sur une double décomposition en valeurs singulières du signal expérimental. Cette méthode par rapport aux précédentes, permet de tenir compte de la diffusion bi ou tridimensionnelle et offre ainsi une meilleure exploitation du contenu spatial des images infrarouges. Des exemples numériques et expérimentaux nous ont permis de valider dans une première approche cette nouvelle méthode d'estimation pour la caractérisation de diffusivités thermiques longitudinales. Des applications dans le domaine du contrôle non destructif des matériaux sont également proposées. Une ancienne problématique qui consiste à retrouver les champs de température initiaux à partir de données bruitées a été abordée sous un nouveau jour. La nécessité de connaitre les diffusivités thermiques du matériau orthotrope et la prise en compte des transferts souvent tridimensionnels sont complexes à gérer. L'application de la double décomposition en valeurs singulières a permis d'obtenir des résultats intéressants compte tenu de la simplicité de la méthode. En effet, les méthodes modales sont basées sur des approches statistiques de traitement d'une grande quantité de données, censément plus robustes quant au bruit de mesure, comme cela a pu être observé
Infrared thermography is a widely used method for characterization of thermophysical properties of materials. The advent of the laser diodes, which are handy, inexpensive, with a broad spectrum of characteristics, extend metrological possibilities of infrared cameras and provide a combination of new powerful tools for thermal characterization and non destructive evaluation. However, this new dynamic has also brought numerous difficulties that must be overcome, such as high volume noisy data processing and low sensitivity to estimated parameters of such data. This requires revisiting the existing methods of signal processing, adopting new sophisticated mathematical tools for data compression and processing of relevant information.New strategies consist in using orthogonal transforms of the signal as a prior data compression tools, which allow noise reduction and control over it. Correlation analysis, based on the local cerrelation study between partial derivatives of the experimental signal, completes these new strategies. A theoretical analogy in Fourier space has been performed in order to better understand the «physical» meaning of modal approaches.The response to the instantaneous point source of heat, has been revisited both numerically and experimentally. By using separable temperature fields, a new inversion technique based on a double singular value decomposition of experimental signal has been introduced. In comparison with previous methods, it takes into account two or three-dimensional heat diffusion and therefore offers a better exploitation of the spatial content of infrared images. Numerical and experimental examples have allowed us to validate in the first approach our new estimation method of longitudinal thermal diffusivities. Non destructive testing applications based on the new technique have also been introduced.An old issue, which consists in determining the initial temperature field from noisy data, has been approached in a new light. The necessity to know the thermal diffusivities of an orthotropic medium and the need to take into account often three-dimensional heat transfer, are complicated issues. The implementation of the double singular value decomposition allowed us to achieve interesting results according to its ease of use. Indeed, modal approaches are statistical methods based on high volume data processing, supposedly robust as to the measurement noise

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17

Hsu, Wen-Chi, and 許文綺. "The Extreme Flash Point Behavior of Ternary Mixtures- The Maximum-Minimum Flash Point." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/nmffp8.

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碩士
國立高雄第一科技大學
環境與安全衛生工程系碩士班
105
The flash point is one of the most important parameters for evaluating the fire and explosion hazards of flammable liquids. The extreme flash point behavior of binary mixtures including the maximum flash point and the minimum flash point. Most of the researches of extreme flash point limited in binary system. However, in the real world, muti-component solutions are used more frequently. In previous study, the minimum flash point behavior of ternary mixture was discussed. However, there is no study discussed about the ternary mixtures which show max-minimum flash point behavior. If we can predict the Max-MinFPB of ternary mixture, it can be applied in hazard reduction and avoiding the potential hazard of fire and explosion on process operation, so this study focus on the Maximum-minimum flash point behavior of ternary mixtures. Beside the experiment data, we also use the prediction model to predict the flash point of mixture which developed for flammable mixtures by Liaw et al. The substances selected included phenol+cyclohexanol+isoamyl butyrate and phenol+1-octanol+acetophenone. Both of them have maximum and minimum flash point. One of the result for the two studied ternary mixtures which have Max-Min flash point in this study is the maximum flash point is the maximum flash point of binary constituent, and the minimum flash point is the minimum flash point of binary constituent. The maximum flash point behavior increase the flash point of mixtures foe the two mixtures. This result can be applied in the hazard reduction of fire and explosion and the design of process operation.

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Li, Yi-Hua, and 李依樺. "Flash point prediction by UNIFAC approach." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/64489391655243426974.

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碩士
中國醫藥大學
職業安全衛生學系碩士班
97
The implementation of GHS (Globally Harmonized System of Classification and Labeling of Chemicals) is the international trend, and Taiwan has implemented GHS since 2008. In the implementation of GHS, the flash point of mixtures is the critical property to classify flammable liquids. The flash point value of liquids is the primary parameter in hazard classification for the flammable liquids. If a flash point prediction model for mixtures is developed, the flash point of mixtures can be estimated rapidly and economically, and it is helpful in the promotion of GHS. The problem of classification of flammable liquids was faced in 2008 in Taiwan, and it is urgently and immediately necessary to be resolved. This study is to give a solution for the estimation of flash point for mixtures, the necessity for classification of flammable liquids. The traditional models for predicting flash point of mixtures usually by the activity coefficient approach. However, the parameters of activity coefficient were regressed from phase equilibrium data in the literatures. If there is no such parameter in literatures for the desired mixture, the model cannot predict the flash point oft hat mixture. Thus, this research aims at the improvement of deficiency of the flash point prediction models in the literatures by useing UNIFAC (Universal Quasi-chemical Functional Group Activity Coefficient) equation, Dortmund-UNIFAC equation and Lyngby-UNIFAC equation. In this study, we were aim at the prediction model for miscible mixtures. From the result, it is suggested to use different type of UNIFAC equation to estimast activivity coefficient in the predition of flash point for different mixture type. In addition to the academic value, the result can be applied to help the government and industries to promote the implementation of GHS. Potential application for the model concerns the assessment of fire and explosion hazards, and the development of inherently safer designs for chemical processes.

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19

LIOU, JYUN-SIAN, and 劉俊賢. "The Study of Flash Point Behavior for Ternary Mixture with Three Binary Constituents Exhibiting Maximum Flash Point." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/jfd2r7.

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碩士
國立高雄第一科技大學
環境與安全衛生工程系碩士班
106
Flammable mixtures have the risk of fire and explosion hazards. The flash point is one of the important reference factors for risk assessment. The composition of the flammable mixture is different, and the flash point behavior is also different. It has been shown in the literature that the binary mixture has the maximum or minimum flash point behavior. In real world, multi-component solutions are used more frequently, and the simplest combination of multi-component mixtures is a ternary mixture. In previous study, the minimum flash point behavior of ternary mixtures was discussed, but the study of the maximum flash point behavior of a ternary mixtures is less. Therefore, this study will investigate the maximum flash point behavior of the ternary mixtures. In the study, we used prediction model of the flash point of a ternary flammable liquid proposed by Liao et al., and used the experimental data as proof. Finally, we discuss the flash point behavior of the ternary mixture. The substances selected included phenol+cycloheptanol+4-tertbutylpyridine and phenol+cycloheptanol+3-butylpyridine. Both have maximum flash point behavior. In this study, we used a flash point analyzer made by Eralytics for analysis and used the ASTM D7094 standard test method of the American Society for Testing and Materials. According to the experimental results of the two studies of ternary mixtures, the maximum flash point is the maximum flash point of binary mixture. According to the characteristics of the maximum flash point behavior, the flash point of the mixture can be increased. This result can be used to reduce the risk of fire and explosion, and can provide a study of the flash point of negative deviation solution.

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20

Chun, Lin Shen, and 林聖鈞. "Binary mixtures exhibiting maximum flash-point behavior." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/22056522365788263759.

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碩士
中國醫藥大學
環境醫學研究所
93
The flash-point specification is one of the major safety data items specified in the typical material safety data sheet, but even those listed in a variety of MSDS sheet are, typically, only valid for a pure and specific compound composition. The existence of maximum flash-point solution was demonstrated in this study. The behavior of such a solution has the potential to be applied in hazard reduction. The sufficient condition for a binary mixture to form a maximum flash-point solution and the equations to determine the maximum flash-point composition and maximum flash-point are proposed here. The derivative of flash point with respect to composition derived previously, which was based upon the flash point-prediction model proposed in a previous study, was applied to derive both the sufficient conditions and equations referred to above. Such a condition and equations both were verified by comparison of predicted results with experimentally derived data. The results reveal that this derived condition is satisfactory for the identification of the status of a liquid solution as being a maximum flash-point solution and the proposed equations satisfactory to successfully estimate the value of the maximum flash-point composition and the maximum flash point. The Flash Point Analyzer, HFP 362-Tag, manufactured by Walter Herzog GmbH (Germany) was used to measure the flash point of liquid solutions associated with different composition as tests. The Flash Point Analyzer is operated according to the standard test method, ASTM D56.

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21

Chen, Hao-Ying, and 陳皓楹. "Investigation of the Ionic Liquid’s Flash Point." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/8dcy38.

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碩士
中國醫藥大學
職業安全與衛生學系碩士班
101
The ionic liquid is considered to be a green solution (the Ionic Liquids ILS).They have a high degree of thermal stability and low volatility. It is proven to be replaced by volatile organic solvents, and can be widely used in other areas. Recently, ionic liquids have been confirmed flammable and classified in a flash point greater than 93 ° C above the liquid Class III B. Most of the research was on the application, unless to discuss about flash point. Studies have demonstrated the generation mechanism of the ionic liquid Flash point is different from the traditional organic solvents. The flash point of ionic liquids can’t be confused with traditional organic solvents. In this research, we use Thermogravimetric analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR) and Flash point tester. We use seven kind of the sample are [C6mim] [Cl], [C4mim] [Cl], [C4mim][ NTf2] [C6mim][NTf2],[C2mim][NTf2], [C10mim][NTf2], [C12mim][NTf2]. Among, [C6mim][Cl] and [C2mim] [NTf2] have been tested in different heating temperatures and use of the FTIR measurements the product of finished testing the flash point. We hope to use the results to identify that the reason of the ionic liquid flash point. In this study, we use the isothermal TGA test [C2mim][NTf2] and [C4mim][NTf2] calculated the kinetic parameters. The results of this study can be used in the prediction flash point of the ionic liquid. And then, the results can be used in hazardous classification of ternary mixtures, and can be applied in process safety design and hazard reduction.

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Chen, Yi-Chien, and 陳怡蒨. "A study of the flash point for ionic liquids." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/96700143045935711584.

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碩士
中國醫藥大學
職業安全衛生學系碩士班
98
This study used dynamic thermogravimetry and FTIR to analyze the gas phase composition before and after the pyrolysis of ionic liquids. The method proposed in literature by use of the thermal diagram of DSC and TGA to estimate the flashpoint of ILs was used and the results were compared with those obtained from flash point tester. A new proposed method by use the tested isothermal TGA decomposition rate at different temperature was tested and was used to estimate the pyrolysis kinetic parameters of ionic liquids. Finally, the estimated flashpoints of ILs were compared with the experimental data. The flash point of ionic liquids was tested by the Flash point tester (Walter Herzog GmbH Pensky-Martens HFP 360). The decomposition behavior of ionic liquids was analyzed by the thermogravimetric analyzer (Mettler Toledo TGA/SDTA851e) and Differential scanning calorimetry (Mettler Toledo DSC821e). The FTIR Multicomponent (FTIR Gas Analyzer GASMET Dx-4015) was used to analyze gas phase composition of the pyrolysis products of ionic liquids. The results tested from dynamic thermogravimetry and FTIR indicated that the gas phase compositions were different. It demonstrated that the estimation of flashpoint of ionic liquids from TGA decomposition data is not appropriate. The method proposed in this study by use of the pyrolysis kinetic parameters from isothermal TGA decomposition rate of ionic liquids. The estimation of flashpoint by use of TGA decomposition data will underestimate the fire and explosion hazard of ionic liquids. By use of the kinetic parameters to estimate flashpoint of ILs proposed in this study give an accuracy result, and reduce the cost of flash point testing.

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Wu, Yu-Shan, and 吳玉珊. "Predictive model of flash point for pure organic substances." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/79bmp7.

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碩士
國立中央大學
化學工程與材料工程研究所
94
Organic substances are used in manufacture processes widely. These substances have many hazardous characters, including toxicity, corrosion, and flammability or combustibility. The flammability has the most concern. Furthermore, flash point is usually used as a flammable index for describing flammability of substances. A predictive model of flash point for organic substances based on the group contribution method is proposed in the study. User can use this model by the groups involving in substance molecule to calculate the flash point without other properties. And building up the predictive model without any restriction is the target of this study.

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24

邱益裕. "the prediction of the flash point for aqueous-organic solutions." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/27968442054698482826.

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碩士
中國醫藥學院
環境醫學研究所
91
A mathematical model for predicting a binary aqueous-organic solutions and an analogous model for predicting the flash point of multiple components aqueous-organic solutions has been proposed, in order to predict the flash point for multi-component solutions. The binary aqueous-organic solutions, water + methanol, water + ethanol, water + n-propanol, and water +2-propanol were used as an example to valid this proposed model for a binary aqueous-organic solutions. The results were plotted against the predictive curves from the flash point prediction model and those simulated by the model described by Crowl & Louvar. The method described by Crowl & Louvar can only be used to estimate the flash point of a binary aqueous-organic solution for the composition range of water composition close to zero, and can not be applied to the composition range of water composition apart from unity. The results reveal that this model is able to precisely predict the flash point over the entire composition range of binary aqueous-organic solutions by way of utilizing the flash-point data pertaining to the flammable component. The ternary aqueous-organic solutions, water + methanol + ethanol, and water + methanol +2-propanol were used as an example to valid this proposed model for a termary aqueous-organic solutions. The results reveal that the model is able to precisely predict the flash point over the entire composition range of multiple components aqueous-organic solutions by way of utilizing the flash point of the individual components. If the binary parameters for a ternary solution are not accessible, such a model based upon the binary parameters of binary solutions may provide a very acceptable means of predicting flash point for a ternary solution as revealed by a comparison between predicted and experimental data. The composition effect on flash point derived in this manuscript can be used in the analysis of the sensitivity of flash point variation for dilution with water, and such a result can be applied in the process safety design/operation to decide if the dilution of a flammable liquid with water is effective at specified composition.

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Huang, Yu-chian, and 黃渝茜. "Analysis of Decomposition Products of Ionic Liquid at Flash Point." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/60238322986355246536.

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碩士
國立高雄第一科技大學
環境與安全衛生工程研究所
103
Ionic Liquids have a high degree of thermal stability, catalyst and extremely low vapor pressure. It as a green solvent and proven to be replaced by volatile organic solvents in industry. Recently, research has been verified that ionic liquids is flammable and be classified in a flash point greater than 93℃ above the liquid Class III B. The reason for ionic liquids combustible is different from the traditional organic solvents defined liquids. The flash point for traditional organic solvent are relative to their vapor pressures, but the cause of flash point for ionic liquid is combustible to vapor pressures.The flash point of ionic point is caused by decomposition. This study is used the Thermogravimetric analysis (TGA) and fourier transform infrared spectroscopy (FTIR) to measure 1-ethyl-3methylimidazolium ethyl sulfate ([Emim][EtSO4])、1-hexyl-3-methylimidazolium chloride ([C6mim][Cl]) and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Bmim][NTf2]). Analysis of decomposition products of ionic liquid flash point by TGA/FTIR is helpful for investigation of the ionic lipqid’s flash point. In this study found that ionic liquid near the flash point will decompose the flammable gas like methanol, ethen, chloromethane etc. Realizing the cause for flammability of ionic liquid is helpful for fire, explosion hazard, process safety design and harzard reduction.

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Chen, Chien-Tsun, and 陳建村. "The flash-point prediction for binary partially miscible aqueous-organic solutions." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/61126106979825604276.

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碩士
中國醫藥大學
職業安全衛生學系碩士班
95
Flash point is the most important variable used to characterize fire and explosion hazard of liquids. Herein, partially miscible mixtures are presented within the context of liquid-liquid extraction processes. This paper describes development of a model for predicting the flash point of binary aqueous-organic solutions with partial miscibility. To confirm the predictive efficacy of the derived flash points, the model was verified by comparing the predicted values with the experimental data for the studied mixtures: water + 1-butanol; water + 2-butanol; water + isobutanol; water + 1-pentanol; and, water + 1-octane. Our results reveal that immiscibility in the two liquid phases should not be ignored in the prediction of flash point. Overall, the predictive results of this proposed model describe the experimental data well. Based on this evidence, therefore, it appears reasonable to suggest potential `application for our model in assessment of fire and explosion hazards, and development of inherently safer designs for chemical processes containing binary partially miscible mixtures of water with one flammable solvent.

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27

Tsai, Tsung-Pin, and 蔡琮彬. "The flash point prediction for partially miscible system by UNIFAC approach." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/55587572217030035061.

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碩士
中國醫藥大學
職業安全與衛生學系碩士班
100
The partially miscible mixtures are used in heterogeneous distillation process and liquid-liquid extraction process. This research aims at the deficiency improvement of necessity of experimental interaction parameters for the flash point prediction models proposed in the literatures by using UNIFAC (Universal Quasi-chemical Functional Group Activity Coefficient) type models. In this study, we were aim at the prediction model for partially miscible mixtures. The partially miscible aqueous-organic mixtures and the partially miscible mixtures of flammable solvents were used to verify the prediction capability of the method. Our results revealed that the combined model is able to represent well the measured flash point over the entire flammable composition range of all studied binary and ternary mixtures, although there are some deviations in the estimated region of two liquid phases. However, we can predict the flash point of binary partially miscible mixtures without experimental binary interaction parameters. Based on this evidence, therefore, it appears reasonable to suggest potential application for our model in the assessment of fire and explosion hazards, and development of inherently safer designs for chemical process containing partially miscible mixtures.

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28

SIE, FU-YUAN, and 謝福源. "The Disappearing Flash Point-Study and Creative Works of Ink Painting." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/3h6skx.

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碩士
國立臺灣藝術大學
書畫藝術學系
106
Artists are quite sensitive in terms to reaction to the environment and convey their opinions toward the society through different forms of art works, expressing their care for the land or society, regardless through critical or implicit approach. In the paper, “The Disappearing Flash Point,” the author starts with self-identity and group identity and converts the author’s emotion of identity into printing. The work reflects the author’s comprehension on the surrounding of the society, where viewers appreciate the aesthetics conveyed from the work of the author and grow reflection for the society due to the sentiment toward the work. The composition of paper displays figures with text, supplemented by literature review. The paper collects different arguments of scholars and various fields of research as reference, probing into the internal idea of works to provide clarify on the creation context and accumulate subsequent strength of creation. The second chapter of the thesis describes the different aspects of identity, mainly exploring the cultural identity of Taiwan. The third chapter of the thesis used different artists as a reference to explore the relevance of self-works. The fourth chapter illustrates the context of self-creation. The fifth chapter concludes with creative experience, and outlines self-reflection and the outlooks of my creation. The author adopts “identity” in the internal idea of works as the focus and apply “self” and “local” as the main orientation of analysis for the various types of identity classification. The author adopts symbol, simplicity and decoration for modes of creation, in an attempt to present the pure and preserve the rhythmic approach for the work. With regards to the materials used for works, except for the “Only Me Series” featuring people, the “Island Series” use the objects of traditional flowers, decomposing and restructuring to interpret the care for the society through natural image. In this era of rapid circulation of information, the expression forms of contemporary arts become even more complicated and hence artists will need to maintain their core value in arts and capture the essence and attitude of advanced techniques in order to maintain their creation strength and grow.

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29

Lu, Wen-Hung, and 呂文宏. "The Flash-Point Prediction for Partially Miscible Mixtures of Flammable Solvents." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/68589709441672612835.

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碩士
中國醫藥大學
職業安全衛生學系碩士班
94
The flash point is one of the major safety data items specified in the typical material safety data sheet, but even those listed in a variety of MSDS sheet are, typically, only valid for a pure and specific compound composition. Flash point is also one of the major quantities used to characterize the fire and explosion hazard of liquids. The partially miscible mixtures are used in liquid-liquid extraction processes. This study presented a model for predicting the flash point of partially miscible of binary flammable solvent. The model was validated using the mixtures, methanol + octane, methanol + 2,2,4-trimethylpentane, ethanol + tetradecane, methanol + decane, acetone + decane and methanol + decane + acetone,respectively. In this study, the mathematical model was derived based on the theory of Vapor-Liquid Equilibrium, Liquid-Liquid Equilibrium and the theory of Le Chatelier’s rule. The Flash Point Analyzer, HFP 360 Pensky-Martens and HFP 362-Tag, manufactured by Walter Herzog GmbH (Germany) were used to measure the flash point of liquid solutions. The Flash Point Analyzers are operated according to the standard test method, ASTM D93 and ASTM D56. The results of this study revealed the model that predicts the flash point for binary partially-miscible mixtures of flammable solvent accurately and it including the flash point at the two margins of two liquid phases. These predictions could be applied to assess the fire and explosion hazard in real environment and safety designs for chemical processes.

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30

CHEN, MAN-CHING, and 陳曼菁. "Study of the Non-flash Behavior of Aqueous-organic Solutions with Substance of Flash Point Being Greater Than 100℃." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/xguwy4.

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碩士
國立高雄科技大學
環境與安全衛生工程系
107
While aqueous-organic mixtures or the leakage of flammable liquids are letting out in the process, it usually dilute water to eliminate fire and explosion hazard. However, this couldn’t be sure that flammability hazard of flammable liquids is eliminated. Therefore, flash point is become the important reference. In the study, the flash point test is to dilute flammable liquids by water, and explore binary aqueous – organic solution under the inerting effects of the lower flammability limit of the gas phase. We found it can not to flash in the test. And the trend is the same as study of Malcolm et al. In the study, we selected substances included water+1,2-ethanediol and water+caprolactam and water+1,4-butanediol and water+2-pyrrolidinone and water+1,2-propanedil, all of them have higher flash points and lower volatility. And we improved the deficiency of the flash point prediction model of Liaw et al., and it was used to predict the upper water level and the maximum flash point of aqueous–organic solution not to flash, and use the experimental data as proof. In 2014, the deficiency of the flash point prediction model of Liaw et al. was only applied in predicting lower flash point and higher volatility, so we improved the liquid phase composition of water and the activity coefficient of water at inerization point, let it apply in all binary aqueous–organic solutions. The results show that this model can successfully forecast the upper water level and the maximum flash point of aqueous–organic solution not to flash. Therefore, such a model can be used to determine whether the organic aqueous mixture is flammable or not.

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31

Chiu, Chao-Yang, and 邱昭陽. "The flash-point prediction for ternary partially miscible mixtures of flammable solvents." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/00925282848019707383.

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碩士
中國醫藥大學
職業安全衛生學系碩士班
96
Flash point is the most important variable used to characterize fire and explosion hazard of liquids. Even that has been listed in a variety of MSDS sheet, it is only valid for pure substance or specific compound composition. The partially miscible mixtures are used in liquid-liquid extraction process and heterogeneous distillation processs. This study intended to present a model for predicting the flash point of ternary partially miscible mixtures of flammable solvents. In this manuscript, the predicting model was derived based on the theory of Vapor-Liquid Equilibrium (VLE), Liquid-Liquid Equilibrium (LLE) and Le Chateliers’ rule. The experimental flash point data were used to validate this proposed model. The flash point analyzer, HFP 362-Tag, manufactured by Walter Herzog GmbH (Germany) was used to measure the flash point of studied mixtures, methanol + toluene + 2, 2, 4-trimethylpentane and acetone + methanol + n- decane. Our results reveal that immiscibility in the two liquid phase should not be ignored in the prediction of flash point. The predictive results of the proposed model could descryibe the experimental data well even it was applied to an immiscible solution. Based on this evidence, therefore, it appears reasonable to suggest potentiall application for our model in assessment of fire and explosion hazards, and development of inherently safer designs for chemical processs containing ternary partially miscible mixtures of flammable solvents.

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32

Thomas, Derrick. "Critical Analysis and Review of Flash Points of High Molecular Weight Poly-functional C, H, N, O Compounds." Thesis, 2011. http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9289.

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The research focuses on the critical review and prediction of flash points of high molecular weight compounds used mainly in the specialty chemical area. Thus far this area of high molecular weight specialty chemicals has not been thoroughly reviewed for flash point prediction; therefore critical review for accuracy of experimental values is difficult. Without critical review, the chance of hazards occurring in the processing and handling of these compounds increases. A reliable method for making predictions is important to efficiently review experimental values since duplicate experimentation can be time consuming and costly. The flash point is strongly correlated to the normal boiling point (NBP) but experimental NBP is not feasible for chemicals of high molecular weight. The reliability of existing NBP prediction methods was found inadequate for our compounds of interest therefore a new NBP prediction method was developed first. This method is based on ten simple group contributions and the molecular weight of the molecule. The training set included 196 high molecular weight C, H, N and O compounds. It produced an average absolute error (AAE) of 13K, superior to any other model tested so far. An accurate NBP is essential for critical review and new method development for flash point. A preliminary data analysis based on chemical family analysis allowed for detection of erroneous data points. These compounds were re-tested at a Huntsman facility. With a predicted normal boiling point, a new FP method that differentiates strong and iv weak hydrogen bonding compounds was developed. This was done because of the differences in entropy of vaporization for hydrogen bonding compounds. The training set consisted of 191 diverse C, H, N, O compounds ranging from 100 to 4000 g/mol in molecular weight. The test set consisted of 97 compounds of similar diversity. Both data sets produced an AAE of 5K and maximum deviation of 17.5K. It was also found that no substantial decomposition was found for these compounds at flash point conditions. These compounds appear to follow the same physical trends as lower molecular weight compounds. With this new method it is possible to critically review this class of chemicals as well as update NBP and other physical property data.
PDF file replaced 4-20-2012 at request of Thesis Office.

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33

Yang, Chieh-An, and 楊傑安. "The study of maximum flash-point behavior for ternary mixtures of flammable solvents." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/16117747754079281658.

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碩士
中國醫藥大學
職業安全與衛生學系碩士班
99
Flash point is the major and important physical property to charactize the fire and explosion hazards of substances in the operatation, transportation and storage of flammable (or combustible) liquid. Different mixtures of flammable solvents appear different flash point behaviors. The study of binary mixtures exhibiting maximum flash point behavior had verified flash point of the mixture may be larger than those of the individual components and it decrease the risk of fire and explosion. However, the number of mixture solvents often larger than two components. Therefore the ternary flammable solvents maximum flash point behavior deserved to investigate. In this study, the flash point of ternary solutions were tested by the flash point tester(Walter Herzog GmbH HFP 362-Tag and HFP 360-Pensky Martens) .Three ternary solutions：phenol＋cyclohexanol＋cyclohexanone, phenol＋acetophenone＋1-propanol and phenol＋cyclohexanol＋benzyl alcohol were used to investigate maximum flash point behavior of ternary solutions. The experimental results were compared with the data of flash point prediction model. The change of flash point behavior at binary maximum flash point mixtures addition of a third component observed in this study. The results displayed three different ternary flash point behaviors, and provided more possible behaviors to classification. The study of negative deviation of multi-component had promoted and reduced the risk of flammable solvents.

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34

Lin, Hsin-Hua, and 林欣樺. "The Flash Point Prediction Model for Organic Compounds Using Quantitative Structure Property Relationship Approach." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/85199786319479513520.

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碩士
國立高雄第一科技大學
環境與安全衛生工程研究所
102
Flash point(FP) is the major index for categorizing the fire hazards of liquid compounds, and it is also one of the important characteristics used for assessing the fire and explosion hazards of a compound. However, due to limitations on experiments, the FP of compounds requires a certain amounts of sample, thus while the sample is of high-priced or is of toxic, there are substantial difficulties for conducting such experiments. Therefore, the prediction of flash points is an important safety subject. In this study, Using the quantitative structure property relationship (QSPR) approach built a model to predict the FP of organic compounds. This FP model is built from a set of 729 organic compounds, which are collected from the DIPPR 2012 database supported by American Institute of Chemical Engineer. The collected 729 organic compounds are randomly divided into a training set of 583 compounds and a testing set of 146 compounds and then Dragon 6 software and CODESSA Pro software are employed to calculate the corresponding molecular descriptors for each compounds. The stepwise regression method are then applied to choose molecular descriptors that are highly correlated with FP. This model has five molecular descriptors, the R2 value to be of 0.9055, the average error in percentage to be of 3.22% and predict the test data with Q2 = 0.8804, the average error in percentage to be of 3.33%.

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35

王慈嫒. "A mathematical model for predicting the flash point of a solution with inorganic salt system." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/74685463517618673684.

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碩士
中國醫藥大學
環境醫學研究所
92
The flash-point specification is one of the major safety data items specified in the typical material safety data sheet, but even those listed in a variety of MSDS sheets are, typically, only valid for a specific compound composition. In this study, a mathematical model which may used for predicting the flash point of a solution with inorganic salt system has been proposed and subsequently verified by experimentally-derived data. In this study, the mathematical model was derived based on the theory of vapor-liquid equilibrium and the theory of Le Chatelier’s rule. The Flash Point Analyzer, HFP 362-Tag, manufactured by Walter Herzog GmbH (Germany) was used to measure the flash point of liquid solutions associated with different compositions as tested. The Flash Point Analyzer is operated according to the standard test method, ASTM D56. The results reveal that this model is able to precisely predict the flash point over the entire composition range of acetone-methanol-inorganic salt system and aqueous-organ solution with inorganic salt system by way of utilizing the flash point data pertaining to the flammable components. The addition of inorganic-salt into a flammable solution is able to reduce the activity coefficient of the liquid solution, such that can increase the flash point of such a solution. Addition of inorganic salt into the flammable solutions would form a solution which is negative deviation from ideal solution, such that increase the flash point of flammable solutions. Such a result can be applied in the process safety design/operation.

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36

CHEN, WAN-CHI, and 陳婉綺. "Predicting Flash Point and Auto-Ignition temperature of Liquid Organic Compounds using Quantitative Structure Activity Relationships Approach." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/cy9nu8.

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碩士
國立高雄第一科技大學
環境與安全衛生工程系碩士班
106
Many flammable materials are used in industrial processes, so avoiding fire hazards is a critical issue for such processes. Liquid organic compounds are most commonly used chemical during process, we use flash point (FP) to determine what category of flammable liquid they are and decide the storage method through its category. Besides we also understand the combustion characteristics of the chemical through the auto-ignition temperature (AIT), and determine what correct specifications of explosion-proof electric equipment is provided for handling such flammable materials in order to effectively prevent the occurrence of fire and explosion. However, using experimental methods to evaluate physical properties of the chemicals is usually time consuming, costly, and it is even precarious for toxic or explosive chemicals. Therefore, REACH regulation encourages the use of cost effective alternatives, such as the Quantitative Structure Activity Relationships (QSAR) approach. Our study retrieved all data from DIPPR 801 database maintained by the American Institute of Chemical Engineers (AIChE), and selected only experimental data to avoid using predicted value to affect the model results. Eventually, 786 experimental data were used to establish a flash point prediction model with four descriptors. This model gives the goodness-of-fit performance (

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37

Wu, Hsuan-Ta, and 吳弦達. "A mathematical model for predicting the flash point of ternary partially miscible mixtures of aqueous-organic system." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/05865227148471033829.

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碩士
中國醫藥大學
職業安全衛生學系碩士班
97
Flash point is a variable used in characterizing fire and explosion hazard of liquids. The partially miscible mixtures are used in heterogeneous distillation process and liquid-liquid extraction process. The purpose of this study is to build a mathematical model to predict the flash point of the ternary partially miscible mixtures of aqueous-organic system. The proposed model was validated by use of water +ethanol + 1-butanol, water + ethanol + 2-butanol and water + 1-butanol + 2-butanol mixtures. The VLLE parameters were used to estimate the span of the tie lines and their flash point, and the VLE parameters were used to estimate the flash point in mutual solubility region. The flash point prediction model was verified by the experimental data to be able to estimate the range of the miscible and partially miscible phase during the simulation, as well as the constant flash point on each tie line.

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38

Patel, Suhani Jitendra. "Integrating Safety Issues in Optimizing Solvent Selection and Process Design." Thesis, 2010. http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8248.

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Incorporating consideration for safety issues while designing solvent processes has become crucial in light of the chemical process incidents involving solvents that have taken place in recent years. The implementation of inherently safer design concepts is considered beneficial to avoid hazards during early stages of design. The application of existing process design and modeling techniques that aid the concepts of ‘substitution’, ‘intensification’ and ‘attenuation’ has been shown in this work. For ‘substitution’, computer aided molecular design (CAMD) technique has been applied to select inherently safer solvents for a solvent operation. For ‘intensification’ and ‘attenuation’, consequence models and regulatory guidance from EPA RMP have been integrated into process simulation. Combining existing techniques provides a design team with a higher level of information to make decisions based on process safety. CAMD is a methodology used for designing compounds with desired target properties. An important aspect of this methodology concerns the prediction of properties given the structure of the molecule. This work also investigates the applicability of Quantitative Structure Property Relationship (QSPR) and topological indices to CAMD. The evaluation was based on models developed to predict flash point properties of different classes of solvents. Multiple linear regression and neural network analysis were used to develop QSPR models, but there are certain limitations associated with using QSPR in CAMD which have been discussed and need further work. Practical application of molecular design and process design techniques have been demonstrated in a case study on liquid-liquid extraction of acetic acid-water mixture. Suitable inherently safer solvents were identified using ICAS-ProCAMD, and consequence models were integrated into Aspen Plus simulator using a calculator sheet. Upon integrating flammable and toxic hazard modeling, solvents such as 5-nonanone, 2-nonanone and 5-methyl-2-hexanone provide inherently safer options, while conventionally-used solvent, ethyl acetate, provides higher degree of separation capability. A conclusive decision regarding feasible solvents and operating conditions would depend on design requirements, regulatory guidance, and safety criteria specified for the process. Inherent safety has always been an important consideration to be implemented during early design steps, and this research presents a methodology to incorporate the principles and obtain inherently safer alternatives.

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39

Natalia, Daniele Dorighello Carareto. "Equilibre solide-liquide et point d'éclair de mélanges de corps gras." Thesis, 2014. http://www.theses.fr/2014PAUU3048/document.

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L’étude des propriétés physico-chimiques des matières grasses constitue une demande mondiale croissante liée à l’augmentation constante de leur utilisation comme source d'énergie et pour l'alimentation. Une bonne connaissance de leurs propriétés thermophysiques et de leur comportement de phases est nécessaire pour la production, l'utilisation efficace de ces matières grasses et le développement des processus d'extraction au niveau du raffinage et du stockage. Des données d'équilibre solide-liquide peuvent être utilisées pour améliorer les procédés existants, et également pour le développement des nouveaux procédés de séparation. Ainsi, le point d'éclair est une propriété importante qui doit être observée pendant le stockage, le transport et la production de composés inflammables, tels que le biodiesel. Ce travail vise à étudier l'équilibre solide-liquide de mélanges binaires constitués d'alcools gras, d’acides gras et d’esters éthyliques. Il porte aussi sur l'évaluation du point d’éclair de mélanges d'esters éthyliques, constituants majoritaires du biodiesel, et de l'éthanol, présent à des niveaux résiduels dans le biodiesel. Les points d’éclair des esters éthyliques mais également des mélanges binaires d'esters éthyliques et d’éthanol, ont été déterminés expérimentalement. Un modèle empirique de prédiction des points d’éclair des biodiesels en fonction de leur composition et de leur teneur en éthanol a été proposé. Les diagrammes de phases solide-liquide des mélanges binaires d'alcool gras + alcool gras ou d’alcools gras + acide gras ont été déterminés expérimentalement par analyse calorimétrique différentielle (DSC). Cette étude permet de caractériser les réactions eutectique, péritectique et métatectique, en utilisant une vitesse de chauffe linéaire ou une méthode de Stepscan DSC. Des mesures de diffraction rayons X et de microscopie optique de contrôle de la température ont été appliquées pour compléter la compréhension des diagrammes de phases. L'effet de la pression sur l'équilibre solide-liquide a aussi été mesuré pour les mélanges binaires d’esters éthyliques ou d'alcools gras en utilisant un microscope optique couplé à une cellule à haute pression qui permet d’augmenter la pression jusqu'à 80 MPa sur une large gamme de température. Les modèles thermodynamiques Margules 2 et 3-suffix et NRTL ont été utilisés pour décrire la ligne du liquidus des systèmes présentant un point péritectique, alors qu’un modèle thermodynamique prédictif a permis de modéliser l'ESL en fonction de la pression. Dans les deux cas, on a observé un ajustement satisfaisant par rapport aux données expérimentales
The study on the physicochemical properties of fatty materials has acquired a growing importance, mainly due to the incentive of their use in energy and nutrition. The efficient production and use of fatty compounds requires a good knowledge of their properties and phase behavior that are necessary for development of processes, especially in production steps such as extraction and refining, but also during storage of the final products. Solid-liquid equilibrium data can be used to improve or propose new separation processes. Also the flash point is an important property that must be considered during storage, transportation and production of flammable compounds, such as biodiesel. This work aimed to study the solid-liquid equilibrium of binary mixtures consisting of fatty alcohols, fatty esters or fatty acids, and to evaluate the flash point of mixtures of ethyl esters, the major constituents of biodiesels, and ethanol, also present in biodiesel in residual levels. Flash points of ethyl esters, and also of the binary mixtures of ethyl esters with ethanol were determined experimentally. An empirical model for predicting the flash point of biodiesels as a function of composition and ethanol content was proposed. The solid-liquid phase diagrams of binary mixtures of fatty alcohol + fatty alcohol or fatty alcohols + fatty acid were determined experimentally by differential scanning calorimetry (DSC), using a linear heating rate, or by a stepscan DSC method, with the aim of investigating the occurrence of the eutectic, peritectic and metatectic reactions. X-ray diffraction and optical microscopy with temperature control techniques were applied to complement the understanding of the phase diagrams. The effect of pressure on the solid-liquid equilibrium was investigated for the binary mixtures of ethyl esters or fatty alcohols using an optical microscope coupled to a high pressure cell which allows the pressure increase up to 80 MPa. Margules 2 and 3-suffix and NRTL thermodynamic models were used for describing the liquidus line of the systems that presented peritectic point, and a predictive thermodynamic model was used to model the ESL function of pressure, which in both cases, gave a satisfactory fit compared to the experimental data

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40

Yuan, Chengwu. "A new relative permeability model for compositional simulation of two and three phase flow." Thesis, 2010. http://hdl.handle.net/2152/ETD-UT-2010-12-2517.

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Chemical treatments using solvents and surfactants can be used to increase the productivity of gas-condensate wells with condensate banks. CMG’s compositional simulator GEM was used to simulate such treatments to gain a better understanding of design questions such as how much treatment solution to inject and to predict the benefits of such treatments. GEM was used to simulate treatments in vertical wells with and without hydraulic fractures and also horizontal wells. However, like other commercial compositional simulators, the flash calculations used to predict the phase behavior is limited to two phases whereas a three-phase flash is needed to accurately model the complex phase behavior that occurs during and after the injection of treatment solutions. UTCOMP is a compositional simulator with three-phase flash routine and attempts were made to use it to simulate such well treatments. However, this is a very difficult problem to simulate and all previous attempts failed because of numerical problems caused by inconsistent phase labeling (so called phase flipping) and the discontinuities this causes in the relative permeability values. In this research, a new relative permeability model based on molar Gibbs free energy was developed, implemented in a compositional simulator and applied to several difficult three-phase flash problems. A new way of modeling the residual saturations was needed to ensure a continuous variation of the residual saturations from the three-phase region to the two-phase region or back and was included in the new model. The new relative permeability model was implemented in the compositional reservoir simulator UTCOMP. This new relative permeability model makes it is unnecessary to identify and track the phases. This method automatically avoids the previous phase flipping problems and thus is physically accurate as well as computationally faster due to the improved numerical performance. The new code was tested by running several difficult simulation problems including a CO2 flood with three-hydrocarbon phases and a water phase. A new framework for doing flash calculations was also developed and implemented in UTCOMP to account for the multiple roots of the cubic equation-of-state to ensure a global minimum in the Gibbs free energy by doing an exhaustive search for the minimum value for one, two and three phases. The purpose was to determine if the standard method using a Gibbs stability test followed by a flash calculation was in fact resulting in the true minimum in the Gibbs free energy. Test problems were run and the results of the standard algorithm and the exhaustive search algorithm compared. The updated UTCOMP simulator was used to understand the flow back of solvents injected in gas condensate wells as part of chemical treatments. The flow back of the solvents, a short-term process, affects how well the treatment works and has been an important design and performance question for years that could not be simulated correctly until now due to the limitations of both commercial simulators and UTCOMP. Different solvents and chase gases were simulated to gain insight into how to improve the design of the chemical treatments under different conditions.
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41

Coelho, Bruna Patrícia Pinheiro Lopes. "Estudo de Otimização de Processo da Unidade de Produção de Fuelóleo Regenerado e Estudo do Potencial de Valorização do Mesmo." Master's thesis, 2020. http://hdl.handle.net/10362/108080.

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O presente trabalho visa o estudo de otimização de uma unidade de produção de Fuelóleo a partir de resíduos oleosos marítimos e industriais, bem como o estudo do potencial de valorização deste fuelóleo. O principal objetivo consiste na produção de um combustível mais limpo e eficiente com maior valor no mercado. Uma primeira etapa de caracterização ao fuelóleo permitiu concluir que este combustível resulta do mix de vários óleos minerais, com teor de enxofre inferior a 1% e cerca de 40% de destilados médios na sua composição. O estudo de mercado ao combustível revelou incerteza na valorização do mesmo, resultado de metas europeias impostas para descarbonização da economia até 2050 e a efeitos da regulamentação IMO 2020. Esta análise demonstrou que o valor atual deste produto pode entrar em declínio num futuro próximo, e que a separação dos destilados existentes no fuelóleo poderia potenciar a sua valorização, com entrada no mercado dos destilados marítimos, nomeadamente MGO (Marine Gas Oil). Foram desenvolvidos 5 cenários de revamping da unidade de fuelóleo existente visando a introdução deste numa nova unidade de destilação para obtenção de um Destilado Médio semelhante ao MGO. Adicionalmente foi estudada a possibilidade de injeção de vapor para potenciar a recuperação de Destilado Médio. Os resultados obtidos com a simulação do processo em Aspen PLUS™ previram que seria possível obter entre 20% a 35% de Destilado Médio, num novo sistema de destilação. Seria possível recuperar 20% com operação a 100mbar e 230˚C ou no máximo 35% numa unidade de destilação nas mesmas condições com adição de vapor no fundo da coluna. Ensaios realizados em laboratório permitiram validar a simulação e demonstraram que as características do Destilado Médio estão de acordo com as grades DMA e DMZ na norma ISO 8217:2017 para destilados marítimos. A análise de viabilidade económica e financeira demonstrou que a introdução da nova unidade garante um VAL de 2M€ e uma TIR de 50% para um cenário base de $ 55 do brent, com um retorno de investimento em aproximadamente 3 anos. Esta análise permitiu concluir que a aceitação do Destilado Médio no mercado será o fator que condicionará a viabilidade deste negócio.

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42

JONZA, JAMES M. "PHYSICAL STUDIES OF THERMOPLASTICS. I. MELTING TEMPERATURE MODIFICATIONS IN BISPHENOL A POLYCARBONATE. II. A MELTING POINT DEPRESSION STUDY OF POLYCARBONATE/POLYCAPROLACTONE BLENDS. III. THERMAL CONDUCTIVITY MEASUREMENTS OF ORIENTED POLYETHYLENES (DIFFUSIVITY, FLASH METHOD, MISCIBILITY, ANNEALING)." 1985. https://scholarworks.umass.edu/dissertations/AAI8602648.

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This dissertation discusses studies relating to the physical properties of thermoplastics. Separate investigations involving the melting temperature of a slow-to-crystallize polymer, thermal behavior of a miscible polymer blend, and thermal conductivity of oriented polyethylenes are presented. Polycarbonate is known to thermally crystallize slowly and to a limited extent, with a range of reported melting points. In this study, the melting temperature of polycarbonate was modified from 195(DEGREES)C to 300(DEGREES)C by employing a sequence of vapor-induced crystallization and annealing treatments. The crystals formed by the treatment with organic vapor act as a precursor state for further crystallization into larger, more perfect lamellae. An equilibrium melting point of 335(DEGREES)C has been obtained for PC from an extrapolation of reciprocal lamellar thickness. FTIR and SEC measurements confirm the Kolbe rearrangement reaction occurs only to a limited extent for the annealing procedure employed. The miscibility of bisphenol A polycarbonate (PC) / poly-(epsilon)-caprolactone (PCL) was investigated using DSC. A single glass transition was found across the compositional diagram, in accordance with an earlier study, yet no depression was observed in the melting points of either PC or PCL. For the PCL-rich blends, Hoffman-Weeks extrapolations are linear, and identical to the PCL homopolymer, thus the Flory ((chi)) interaction parameter must be zero or slightly positive for this blend. The PC Hoffman-Weeks extrapolation could not be made, since the blends are reactive at high crystallization temperatures. This reaction was demonstrated by FTIR, NMR, and turbimetric titration to be thermo-oxidative chain branching rather than transesterification between these two polyesters. Thermal conductivity measurements are not a routine experimental technique in the field of polymer science. In this dissertation, experimental methods for cylindrical and film sample geometries are explored. The flash technique for thermal diffusivity has been critically examined with regard to rear-face rise and front-to-rear temperature difference modes of analysis on a systematic series of drawn low-density polyethylenes. Correction procedures have been put forth for losses due to radiation and surrounding air. The increase in thermal conductivity was shown to be proportional to draw ratio. Work on a steady-state fin and a pulsed method for thin film measurements is also discussed.

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Leung, Ming-Kei, and 梁銘基. "First flush analysis of agricultural non-point source." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/46935419760533270469.

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碩士
國立成功大學
環境工程學系碩博士班
96
Stormwater runoff was monitored on 6 separate agricultural watersheds, which were chosen to represent distinct types of farming and spreading chicken fields, along with various watershed characteristics. A total of 57 storm events were monitored to investigate the first flush phenomenon. There are two first flush phenomenon definition, one is concentration first flush(CFF), another is mass first flush(MFF). CFF may be defined as the initial period of stormwater runoff during which the concentration of pollutants is substantially higher than during later stages. MFF may be defined as the initial period of stormwater runoff during which the quality of pollutants throughout the majority of the pollution load. The magnitude of the first flush phenomenon was calculated using a method of data analysis which results in determining the dynamics event mean concentration ratio(REMC) and mass first flush ratio(MFFn). In addition, statistical and graphical correlation analysis of the REMC and MFFn with storm characteristics and environmental factors was made to determine if the first flush is related to site or storm characteristics. As the results, although the percentage of impervious area near zero, we can still be found strength to moderate concentration first flush phenomenon and moderate to mild mass first flush phenomenon in agricultural area. The results and analyses performed also indicates that the concentration first flush phenomenon of SS,COD and TP correlate well with total rainfall, total runoff and rain time but there are no correlation between the mass first flush phenomenon. No correlation was observed between the first flush phenomenon and area, slope and porosity. In this study, through cluster analysis proved that the first flush phenomenon in agricultural areas occurred mainly on non-soluble pollutants.

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Tsai, Yi-Chen, and 蔡宜珍. "Prediction of Flash Points Using Quantitative Structure Property Relationship Approach." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/93996806301460900631.

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碩士
中國醫藥大學
職業安全與衛生學系碩士班
99
Flash point (FP) is the primary property to classify flammable liquids for the purpose of assessing their fire and explosion hazards. Because of the advancement of technology in discovery or synthesis of new compounds, there is often a significant gap between the demand for such data and their availability. In this regard a reliable theoretical method to estimate the FP is indispensable. Although many works of predicting FP have been reported in literature, most methods require other physical properties to predict FP. However, the Quantitative Structure Activity Relationship (QSAR) approach could predict the desired property without using any other properties by experiment, and this is the reason why the REACH regulation adopt this approach as one of the an alternative methods while experimental data are unavailable. In this work, a QSPR studies are presented for predicting the FP of a data set of 230-organosilicon compounds and 1565-organic compounds, respectively. The collected 230 organosilicon compounds are randomly divided into a training set of 184 compounds and a testing set of 46 compounds. Then stepwise regression method is used to select the required molecular descriptors for predicting the FP of organosilicon compounds from 1538 candidate descriptors. Depending on the p-value for accepting a descriptor to enter the model, models with different number of descriptors are obtained. A 13-descriptor model and a 6-descriptor model are obtained with the p-value of 5 × 10-4 and 1 × 10-5, respectively. It is found that the 6-descriptor model could fit the training data with R2 = 0.8981 and predict the test data with Q2 = 0.8533 and the 13-descriptor model could fit the training data with R2 = 0.9293 and predict the test data with Q2 = 0.9245. On the other hand, the collected 1565 organic compounds are also randomly divided into a training set of 1254 compounds and a testing set of 311 compounds. The genetic algorithms and stepwise regression method are used to select the required molecular descriptors from 1785 candidate descriptors. A 10-descriptor model is obtained with the p-value of 5 × 10-16, and it is found that this model could fit the training data with R2 = 0.8958 and predict the test data with Q2 = 0.9210.

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