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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Caracterização PVT de petróleo contendo CO2 / Characterization PVT of petroleum containing CO2

Elias Junior, Antonio, 1980- 08 March 2015 (has links)
Orientador: Osvair Vidal Trevisan / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-28T11:42:17Z (GMT). No. of bitstreams: 1 EliasJunior_Antonio_D.pdf: 4086783 bytes, checksum: 191c12f04f51818fb12b75a3c273b418 (MD5) Previous issue date: 2015 / Resumo: O presente trabalho trata da caracterização experimental de petróleo em misturas contendo diferentes conteúdos de CO2. Os resultados experimentais são analisados através de correlações de propriedades PVT e de simulação computacional. O trabalho visa atender a notável carência de dados públicos sobre propriedades termodinâmicas de petróleo contendo CO2. Os dados PVT avaliados neste estudo contemplam ponto de bolha, ponto de orvalho, razão de solubilidade do óleo, fator volume-formação do óleo, fator volume-formação do gás, fator de compressibilidade do gás, fator de inchamento do óleo, massa específica do óleo, densidade do gás, viscosidade do óleo. São também avaliadas as cromatografias do óleo do reservatório, recombinado e também as cromatografias dos gases coletados durante o ensaio de liberação diferencial. As correlações utilizadas na análise resultados foram as de Standing, Valko-McCain, Al-Shammasi, Dindoruk, Beggs-Robinson e Vasquez & Beggs. Os principais fatores de seleção das correlações foram o espectro de dados dos quais se originaram as correlações e a média do erro relativo absoluto. As correlações selecionadas reproduziram bem os resultados obtidos no laboratório para o fator volume-formação, a razão de solubilidade do gás, o ponto de bolha e a viscosidade. A simulação computacional foi aplicada na análise dos resultados e na obtenção do envelope de fases da mistura através do ajuste da equação de estado de Peng-Robinson. O método usado para a simulação foi o de Coats & Smart, porém foram feitas modificações desse método para um melhor ajuste. O método adaptado reproduziu adequadamente os dados experimentais, sendo que todos os ajustes apresentaram um desvio padrão percentual menor que 6%. O envelope de fases descrito pelo simulador é considerado representativo do sistema, com boa aproximação. Com os resultados obtidos, foram realizadas análises das propriedades da mistura e do comportamento do equilíbrio de fases em decorrência das variações das concentrações molares de CO2, da temperatura e da pressão. Foi a constatado o surgimento de uma terceira fase líquida em algumas condições de tese configurando um equilíbrio L-L-V / Abstract: The present work refers to the experimental characterization of petroleum mixtures with variable contents of CO2. The experimental results are, analyzed via PVT properties correlations and computer model simulations. The work aims to cover the remarkable lack of public data on thermodynamic properties of petroleum containing CO2. The PVT data analyzed in the study comprise bubble point, dew point, oil solubility rate, gas and oil formation volume factor, gas compressibility factor, swelling test, oil density, gas density, oil viscosity. The chromatography of the recombined reservoir oil and also the chromatography of gases mixture collected during the differential liberation test are also evaluated. The correlations used in the analysis of the results were Standing, Valko-McCain, Al-Shammasi, Dindoruk, Beggs-Robinson e Vasquez & Beggs. The principal criteria used in the selection of the correlations were the range of data which originated the correlations and the average absolute relative error. The correlations reproduced well the results obtained in the laboratory for the formation volume factor, gas solubility ratio, bubble point and viscosity. The computer model simulation was used to analyze the data and also to define the phase envelope of the mixture by adjusting Peng-Robinson's state equation. The method used in the simulation was developed by Coats & Smart, but some modifications were made to obtain a better match. The modified method reproduced adequately the experimental results, within a standard deviation less than 6%. The phase envelope obtained from the simulation is considered, with good approximation, representative of the system. Once with the results obtained were performed analyses of the properties and phase equilibrium behavior of the mixture related with the CO2 molar concentration, temperature and pressure. A third liquid phase was observed in some conditions of the tests configuring a L-L-V phase equilibrium / Doutorado / Reservatórios e Gestão / Doutor em Ciências e Engenharia de Petróleo
2

Otimização de uma unidade de destilação de solvente.

BATISTA, Rodrigo Albuquerque. 26 July 2018 (has links)
Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-07-26T20:04:29Z No. of bitstreams: 1 RODRIGO ALBUQUERQUE BATISTA – DISSERTAÇÃO (PPGEQ) 2009.pdf: 1371116 bytes, checksum: e83cb01217e145c19452e17728123ea0 (MD5) / Made available in DSpace on 2018-07-26T20:04:29Z (GMT). No. of bitstreams: 1 RODRIGO ALBUQUERQUE BATISTA – DISSERTAÇÃO (PPGEQ) 2009.pdf: 1371116 bytes, checksum: e83cb01217e145c19452e17728123ea0 (MD5) Previous issue date: 2009-03-31 / A destilação é um dos processos de separação mais importantes e que também, mais consomem energia em indústrias químicas e petroquímicas. Portanto sua operação otimizada é condição sine qua non para viabilidade dos negócios. Além do alto consumo, em alguns processos ocorre a formação de compostos azeotrópicos que se mantêm presentes na destilação; estes se classificam entre homogêneos e heterogêneos. Este trabalho abordou a otimização do sistema de purificação de solvente (trem de destilação) de uma das unidades da Braskem, o qual é constituído por duas colunas de destilação e um vaso de flash. A planta onde está localizado o sistema de purificação produz polietilenos de Alta Densidade (PEAD) e de Ultra Alto peso Molecular (PEUAPM) através da tecnologia Slurry. A polimerização é realizada em suspensão de solvente e utiliza reatores do tipo mistura perfeita (CSTR). A perda de solvente e o consumo de vapor representam 80% do custo variável após matérias primas da planta de produção de polietileno de alta densidade tecnologia slurry da MCI – Mitsubishi Chemical Inc. A otimização das colunas de destilação da Planta PE2 da Braskem utilizando modelo termodinâmico de Peng Robinson através do simulador comercial Aspen Plus demonstrou potencial de economia de 1.200.000 R$/ano. / The distillation is the most important separation process in chemical engineer, on the other hand it is the highest industry energy consumer. Therefore, optimized operation is essential to business feasibility. In some process happen the azeotropic moisture is formed that is hold in the distillation section, they can be classified as homogeneous or heterogeneous. This work approached the optimization of the Solvent Purification System (distillation train) from Braskem PE2 unit who is built up from to two distillation columns and one flash drum. The PE2 unit who produce High Density Polyethylene and Ultra High Molecular Weight Polyethylene by slurry process from Mitsubishi Chemical Corporation is localized in Camacari, Brazil. The polymerization is conduced in a solvent suspension and use Continuous Stirred Tank Reactor (CSTR) type. The solvent lost and the steam consumer together the 80% from the variable cost, before raw material, in High Densit y Polyethylene and Ultra High Molecular Weight Polyethylene by slurry process from Mitsubishi Chemical Corporation. The optimization from Braskem PE2 Unit distillation system, using thermodynamic model Peng Robinson through the Aspen Plus commercial simulator presented 1.200.000 R$/y.
3

Estudo Experimental e modelagem termodinamica do equilibrio de fases (liquido-liquido e liquido-vapor) de sistemas de interesse da industria de fenol / Experimental study and thermodynamic modeling of phase equilibrium (liquid-liquid and liquid-vapor) of systems regarding phenol industry

Mafra, Marcos Rogerio 29 April 2005 (has links)
Orientador: Maria Alvina Krahenbuhl / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-04T13:24:40Z (GMT). No. of bitstreams: 1 Mafra_MarcosRogerio_D.pdf: 5218448 bytes, checksum: 82785bbe534f8328a5b2d6c5c2a8c306 (MD5) Previous issue date: 2005 / Resumo: O estudo dos fenômenos físico-químicos presentes nos processos químicos industriais é de extrema relevância, desde o projeto ata a operação das unidades que compõem a planta. Dentre as etapas do processo, a separação e purificação costumam concentrar os maiores custos do projeto. Um importante segmento da indústria petroquímica é a produção de fenol, empregando na fabricação de resinas. Nesse processo duas colunas de destilação e um decantador são responsáveis pela purificação do fenol e recuperação da matéria-prima (cumeno). O equilíbrio de fases é um dos fenômenos mais importantes dessas unidades, havendo a possibilidade de ocorrer em alguns pratos o equilíbrio trifásico (LLV). Embora termodinamicamente possível, as tentativas de descrever essa forma de equilíbrio, utilizando dados exclusivamente bifásicos (LL /ou LV), não apresentam bons resultados. Este trabalho teve como objetivo o estudo termodinâmico do equilíbrio líquido-líquido e líquido-vapor na região próxima ao equilíbrio líquido-líquido-vapor de sistemas que compõem as etapas de separação do processo de produção fenol (água, acetona, 'alfa¿-metil estireno, cumeno e fenol), de forma a contribuir com o estudo do equilíbrio trifásico, presente nesse processo. Foram obtidos dados isotérmicos de equilíbrio líquido-líquido a 50 e ¿60 GRAUS¿C e dados isobáricos de equilíbrio líquido-vapor à 760 mmHg... Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Studies concerning physical and chemical phenomena are very important for the chemical industry, form the early stages of design up to full plant operation. Among the many units that make up a chemical plant, the last steps of separation and purification stands as the most expensive. Phenol, used to produce resins as well as other products, is an important feedstock to petrochemical industries. Two distillations columns and one decanter are used to purify phenol and separate cumene in the phenol production process, in which phase equilibrium plays an important role. In a tray distillation tower, one may find two liquid phases and one vapor phase in equilibrium (VLLE). Although possible, attempts to describe this equilibrium condition from two phase equilibrium conditions, either liqui-liquid (LLE) or vapor-liquid (VLE), haven¿t succeed. The objective of this work was to study the LLE and VLE of systems comprising components of the phenol production process, i.e., water, acetone, cumene, phenol and 'alfa¿-methyl styrene, at conditions close to the liquid-liquid-vapor equilibrium. Equilibrium data were successfully obtained at ¿50 DEGREES¿C and ¿60 DEGREES¿C and at 760 mmHg for a variety of compositions. Unfortunately data at high acetone contents could not be obtained due to the high pressure generated in the experimental apparatus... Note: The complete abstract is available with the full electronic digital thesis or dissertations / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química
4

Phasengleichgewichte in komplexen Modellsystemen aus Phenolen, Kohlenwasserstoffen und Wasser

Martin, Antje 02 July 2014 (has links)
Die experimentelle Charakterisierung von Phasengleichgewichten (Flüssigkeit-Dampf und Flüssigkeit-Flüssigkeit) erfolgte in binären und ternären Systemen aus aromatischen bzw. aliphatischen Kohlenwasserstoffen, Phenolen und Wasser. Die Trübungstitration diente der Bestimmung von Flüssigkeit-Flüssigkeit-Gleichgewichten, auftretende koexistierende flüssige Phasen wurden analytisch charakterisiert. Mit Hilfe der dynamischen Methode erfolgte die Bestimmung der Flüssigkeit-Dampf-Gleichgewichte. Die Modellierung der binären Systeme und die Vorausberechnung der ternären Systeme erfolgten mit den Aktivitätskoeffizientenmodellen NRTL und UNIQUAC. Weiterhin wurden die Berechnungen mit der von Elliott, Suresh und Donohue entwickelten Zustandsgleichung (ESD) durchgeführt, welche einen die assoziierenden Wechselwirkungen berücksichtigenden Term beinhaltet. Ferner wurden mit der Gruppenbeitragsmethode UNIFAC die untersuchten binären und ternären Systeme vorausberechnet. Beide Aktivitätskoeffizientenmodelle können bei der simultanen Modellierung der verfügbaren Phasengleichgewichtsdaten für nahezu alle betrachteten binären Systeme mit sehr guten Ergebnissen überzeugen. Bei der Modellierung mit der Zustandsgleichung ESD müssen deutlich höhere Abweichungen akzeptiert werden. Die Ergebnisse der Modellierung der binären Systeme lassen sich nicht adäquat auf die Vorausberechnung der ternären Systeme übertragen. UNIQUAC Modell und Zustandsgleichung ESD zeigen im Mittel die geringsten Unterschiede zwischen vorausberechneten und experimentellen Phasengleichgewichten. Deutlich höhere Abweichungen treten im Mittel bei Verwendung des NRTL Modells bzw. der Gruppenbeitragsmethode UNIFAC auf. Die Annahme, mit Hilfe der expliziten Berücksichtigung der Assoziation mit Zustandsgleichung ESD eine deutliche Verbesserung bei der Vorausberechnung entsprechender Phasengleichgewichten zu erzielen, konnte lediglich für Flüssigkeit-Flüssigkeit-Gleichgewichte in Systemen mit aliphatischen Kohlenwasserstoffen bestätigt werden. / The experimental characterizations of phase equilibria (vapor-liquid and liquid-liquid) were determined in binary and ternary systems containing aliphatic and aromatic hydrocarbons, phenols and water. Liquid-liquid equilibria were measured by turbidity titration. The compositions of coexisting phases were determined with analytic methods. The vapor-liquid equilibria were determined by the dynamic method. The correlation of the binary systems and the prediction of the ternary systems were performed with the activity coefficient models NRTL and UNIQUAC. Furthermore the calculations were realized with an equation of state (ESD) developed by Elliott, Suresh and Donohue, which contain a term for association. Additional predictions of investigated binary and ternary systems were performed with the group contribution method UNIFAC. Both activity coefficient models convinced with satisfactory results by the simultaneously correlation of the available equilibria data for almost all investigated binary systems. The correlations with the ESD equation of state were performed with higher deviations. A transfer of the results of the binary correlations into the ternary predictions is not possible. The UNIQUAC model and the ESD equation of state performed on average with minor deviations between predicted and experimental phase equilibria. Higher deviations were calculated using the NRTL model respectively the group contribution method UNIFAC. Only liquid-liquid equilibria in systems contain aliphatic hydrocarbons indicates improved prediction results based on the consideration of the association.
5

Untersuchung der Phasengleichgewichte in Systemen mit assoziierenden Komponenten

Klauck, Mandy 09 October 2009 (has links)
Die Phasengleichgewichte (Flüssigkeit-Dampf und Flüssigkeit-Flüssigkeit) der binären, ternären und quaternären Mischungen bestehend aus Wasser, Toluen, Anilin und Cyclohexylamin wurden experimentell bestimmt und modelliert bzw. vorausberechnet. Die Bestimmung der Flüssigkeit-Dampf-Gleichgewichte erfolgte mit Hilfe der dynamischen Methode, die dafür notwendige Mess- und Regeltechnik wurde erweitert und modernisiert. Die Flüssigkeit-Flüssigkeit-Gleichgewichte wurden durch Trübungstitration und Analyse der koexistierenden Phasen bestimmt. Die Beschreibung der binären Systeme und die Vorausberechnung der Mehrkomponentensysteme erfolgte mit den Aktivitätskoeffizientenmodellen UNIQUAC und NRTL und der Zustandsgleichung, entwickelt von Elliott, Suresh und Donohue (ESD). Die ESD-Zustandsgleichung enthält neben einem Attraktions- und einem Repulsionsterm auch einen Term, der assoziative Wechselwirkungen explizit berücksichtigt. Die Beschreibung der binären Systeme gelingt mit den getesteten Modellen sehr gut. Dabei werden mit den Aktivitätskoeffizientenmodellen bessere Ergebnisse erreicht als mit der ESD-Zustandsgleichung. Diese Bild kehrt sich bei der Vorausberechnung der Mehrkomponentensysteme um. Bei Verwendung der NRTL-Gleichung treten deutlich höhere Abweichungen auf als bei Berechnungen mit der ESD-Zustandsgleichung bzw. der UNIQUAC-Gleichung. Die Erwartung durch explizite Berücksichtigung der Assoziation mit der ESD-Zustandsgleichung einen deutlichen Vorteil in der Vorhersage von Phasengleichgewichten in Systemen mit assoziierenden Komponenten zu erhalten konnte in den untersuchten Mischungen nicht eindeutig bestätigt werden. / Phase equilibria (vapor-liquid and liquid-liquid) of binary, ternary and quaternary systems consisting of water, toluene, aniline and cyclohexylamine were determined experimentally and modeled resp. predicted. Vapor-liquid equilibria were determined by the dynamic method, the necessary measuring and control systems were extended and modernized. Liquid-liquid equilibria were investigated by turbidity titration and analyses of coexisting phases. The calculation of the binary systems and the prediction of the multicomponent systems were performed with the activity coefficient models UNIQUAC and NRTL and the equation of state developed by Elliott, Suresh and Donohue (ESD). The ESD equation of state includes beside an attractive and a repulsive term a term for explicit consideration of associative interaction. The description of the binary systems succeeded very well with the tested models. Better results were achieved with the activity coefficient models than with the ESD equation of state. These findings are inversed in the case of prediction of multicomponent phase equilibria. On application of the NRTL equation the deviations are notable greater than with the ESD equation of state or the UNIQUAC equation. The expectation to get a significant advantage in prediction of phase equilibria in systems with associating components with the ESD equation of state could not be answered definitely.

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