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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.
11

Development of a novel monolith froth reactor for three-phase catalytic reactions /

Crynes, Lawrence Lee. January 1993 (has links)
Thesis (Ph.D.)--University of Tulsa, 1993. / Five colored photographs glued in book. Includes bibliographical references.
12

Modelagem e simulação de reatores gas-solido de escoamento descendente (Downer) / Modeling and simulation of cocurrent downflow reactor (Downer)

Silva, German Gonzalez 12 August 2018 (has links)
Orientador: Antonio Carlos Luz Lisboa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-12T15:53:08Z (GMT). No. of bitstreams: 1 Silva_GermanGonzalez_M.pdf: 1967268 bytes, checksum: fb1da8c45ce0a2b393f58ef9ab9d72d0 (MD5) Previous issue date: 2008 / Resumo: Os reatores de leito fluidizado são uma das mais importantes tecnologias atuais para processos heterogêneos gás-sólido, tanto catalíticos como não catalíticos. As aplicações industriais mais importantes incluem o craqueamento catalítico na indústria petroquímica, a combustão e/ou gaseificação de carvão, biomassa e resíduos sólidos. Estes são importantes processos para a geração de energia, produção de combustíveis e gás de síntese. Um dos tipos de reatores de leito fluidizado mais relevante é o reator de fluxo ascendente conhecido como riser. Este reator consiste de uma coluna tubular na qual o sólido e o gás escoam co-correntes de forma ascendente. Em comparação com outras tecnologias, o reator riser tem uma importante desvantagem: uma distribuição de tempos de residência variada no reator que reduz a conversão e a seletividade. Recentemente cresceu o interesse por outro tipo de reator gás-sólido circulante que possui melhor desempenho que o reator riser. Neste tipo de reator, conhecido como downer, por oposição ao riser, o escoamento co-corrente gás-sólido ocorre de forma descendente, o que lhe outorga características fluidodinâmicas que se assemelham mais ao escoamento tipo pistão e permitem um melhor controle da conversão, da seletividade e da desativação. O objetivo deste trabalho é estudar a simulação de reatores gás-sólido tipo downer, incorporando modelos fluidodinâmicos com modelos de engenharia das reações químicas e catalíticas. Desenvolve-se, de forma geral, a modelagem dos diferentes fenômenos fluidodinâmicos, físico-químicos e catalíticos que ocorrem no reator e são propostos algoritmos de solução para diferentes situações. Posteriormente, aplica-se o modelo proposto do reator downer ao estudo de um caso industrial: o craqueamento catalítico. Os resultados mostram um enfoque geral aplicável para a modelagem e simulação de sistemas de reações gás-sólido em fluxo descendente. As simulações do processo industrial de craqueamento catalítico revelam que o reator tipo downer apresenta características de desempenho que o fazem superior ao reator tipo riser convencional. / Abstract: The fluidized bed reactor is one of the most important technologies for gas-solid heterogeneous operations, considering catalytic or non catalytic processes. The most important industrial applications include catalytic cracking, coal combustion and biomass combustion. The most relevant fluidized bed reactor is the ascendant flow reactor, which is known as riser. The riser reactor consist of a tubular column in which the solid and the gas flow cocurrently upward. The riser reactor has as main disadvantage a wide residence time distribution, which reduce the conversion and the selectivity. Recently, it has grown the interest in a new type of gas-solid circulating reactor with a better performance than the riser which is known as downer. In this reactor the gas and the solid flow cocurrently downward, creating hydrodynamic features comparable to a plug flow reactor and allowing a better control over the conversion, the selectivity and the deactivation. This work regarded it had been studied the simulation of the gas-solid downer reactor, including hydrodynamic models and models from the chemical reaction engineering. It was developed in a general way the modelling of the hydrodynamic, physical chemical and catalytic phenomena occurring in the reactor. Algorithms were proposed to solve of different simulation cases. The proposed model of the downer reactor was used in the studying of one industrial case: the catalytic cracking. The results show a general approach which is applicable for modelling and simulation of gas-solid reactive system with descendent flow. The simulations of the catalytic cracking show that the downer reactor has features that make it perform better than the conventional riser reactor. / Mestrado / Engenharia de Processos / Mestre em Engenharia Química
13

Activated Sludge as Renewable Fuels and Oleochemicals Feedstock

Revellame, Emmanuel Durante 09 December 2011 (has links)
The utilization of activated sludge as feedstock for biofuel and oleochemical production was investigated. Initial studies included optimization of biodiesel production from this feedstock through in situ transesterification. Results of these studies indicated that activated sludge biodiesel is not economically viable. This was primarily due to relatively low yields and the high economics of feedstock dewatering. Strategies to increase biofuel yield from activated sludge were then evaluated. Bacterial species present in activated sludge are known to produce a wide variety of lipidic compounds as carbon and energy storage material and as components of their cellular structures. In addition to lipidic compounds, activated sludge bacteria might also contain other compounds depending on wastewater characteristics. Among these bacterial compounds, only the saponifiable ones can be converted to biodiesel. The unsaponifiable compounds present in the activated sludge are also important, not only for biofuel production, but also for a wide variety of applications. Characterization of lipids in activated sludge revealed that it contains significant amount of polyhydroxyalkanoates, wax esters, acylglycerides and fatty acids. It also contains Template Created By: James Nail 2010 sterols, steryl esters and phospholipids as well as small but detectable amounts of hydrocarbons. This indicated that activated sludge could be also an inexpensive source of oleochemicals. Another strategy that was evaluated was lipid-enhancement by fermentation of activated sludge. Since the majority of products from petroleum oil are used as transportation fuel, the aim here was to increase the saponifiable lipids in activated sludge bacteria by applying a biochemical stimulus (i.e. high C:N ratio). Results showed that application of this stimulus increased the amount of saponifiable lipids, particularly triacyglycerides, in the activated sludge. Furthermore, fermentation homogenized the lipids in the sludge regardless of its source. This solidified the concept of utilizing wastewater treatment facilities as biorefineries. To support the utilization of other compounds in raw activated sludge for biofuel production, a model compound was chosen for catalytic cracking experiments. Results indicated that catalytic cracking of 1-octadecanol over H+ZSM5 proceeds via dehydration, producing octadecene. The octadecene then undergoes a series of reactions including β-C─C bond scission, alkylation, oligomerization, dehydrocyclization and aromatization producing aromatics, paraffins and olefins suitable for fuel applications.
14

A Review of Modelling of the FCC Unit. Part I: The Riser

Selalame, Thabang W., Patel, Rajnikant, Mujtaba, Iqbal M., John, Yakubu M. 18 March 2022 (has links)
yes / Heavy petroleum industries, including the fluid catalytic cracking (FCC) unit, are useful for producing fuels but they are among some of the biggest contributors to global greenhouse gas (GHG) emissions. The recent global push for mitigation efforts against climate change has resulted in increased legislation that affects the operations and future of these industries. In terms of the FCC unit, on the riser side, more legislation is pushing towards them switching from petroleum-driven energy sources to more renewable sources such as solar and wind, which threatens the profitability of the unit. On the regenerator side, there is more legislation aimed at reducing emissions of GHGs from such units. As a result, it is more important than ever to develop models that are accurate and reliable, that will help optimise the unit for maximisation of profits under new regulations and changing trends, and that predict emissions of various GHGs to keep up with new reporting guide-lines. This article, split over two parts, reviews traditional modelling methodologies used in modelling and simulation of the FCC unit. In Part I, hydrodynamics and kinetics of the riser are dis-cussed in terms of experimental data and modelling approaches. A brief review of the FCC feed is undertaken in terms of characterisations and cracking reaction chemistry, and how these factors have affected modelling approaches. A brief overview of how vaporisation and catalyst deactiva-tion are addressed in the FCC modelling literature is also undertaken. Modelling of constitutive parts that are important to the FCC riser unit such as gas-solid cyclones, disengaging and stripping vessels, is also considered. This review then identifies areas where current models for the riser can be improved for the future. In Part II, a similar review is presented for the FCC regenerator system.
15

The effect of feed rate and cracking time on carbon formation during the catalytic cracking of petroleum hydrocarbons

Hill, Roger W. January 1948 (has links)
The process of catalytic cracking of petroleum hydrocarbons invariably produces a carbonaceous deposit on the surface of the solid catalyst which serves to reduce the activity of the catalyst. This investigation was undertaken to determine the effect of the feed rate and the length of the cracking period on the carbon formation on the catalyst. A vertical, fixed-bed, externally heated reactor was constructed. The reactor contained a bed of synthetic silica-alumina Socony-Vacuum bead catalyst. The necessary auxiliary apparatus required to handle the feed and the products of reaction was provided. The amount of carbon deposited on the catalyst was determined by burning it and measuring the carbon dioxide thus formed. The feed material used was Esso Diesel Oil (208). It was exposed to the catalyst at a temperature of about 900 degrees Fahrenheit for a series of ten minute periods while the feed rate was varied from 0.42 to 5.55 volumes of feed per volume of catalyst per hour. Another series of tests was performed at the same temperature, the feed rate being held at approximately two volumes of feed per volume of catalyst per hour; while the length of the cracking period was varied between thirty-five seconds and thirty minutes. It was found that during the ten minute cracking periods the amount of carbon deposited on the catalyst was independent of the feed rate between the limits of 0.91 and 5.55 volumes of feed per volume of catalyst deposited on the catalyst was related to the length of the cracking period by a parabolic function. Further analysis of the data revealed that the amount of feed converted into carbon was related to the degree of conversion by a parabolic function. From the three relations mentioned above, an equation relating the conversion, the feed rate and the cracking period was derived. The form of this equation is as follows: V³⋅⁰ = (9.60 x 10⁵)/R<sub>fv</sub> t⁰⋅⁷⁵ where V is the percent conversion, R<sub>fv</sub> is the feed rate and t is the cracking time in minutes. It was further found that the activity of the catalyst was not materially decreased after a series of twenty-nine tests, but that the substitution of quartz chips for the catalyst in the reactor decreased the conversion obtained by 75 per cent. / M.S.
16

Experimental and modeling study of a cold-flow fluid catalytic cracking unit stripper

Wiens, Jason Samuel 22 June 2010
Many particulate processes are preferably implemented in circulating fluidized beds (CFB) over traditional low-velocity fluidization to take advantage of the many benefits of circulating systems. Fluid catalytic cracking (FCC) is one of the most successfully applied processes in CFB technology, with more than 350 FCC units in operation worldwide. Despite its extensive use, an understanding of the complex behaviour of these units is incomplete.<p> A theoretical and experimental evaluation of the fluidization behaviour was conducted in the CFB riser, standpipe, and stripper. Initially, an extension of the existing CFB in the Fluidization Laboratory of Saskatchewan was designed. The experimental program conducted in this study included an examination of the solids flow behaviour in the riser, interstitial gas velocity in the downcomer, and stripping efficiency measurements. The hydrodynamic behaviour of the stripper was modeled using Multiphase Flow with Interphase eXchanges (MFIX) CFD code.<p> The solids flow behaviour in the bottom zone of a high-density riser was investigated by measuring the local upwards and downwards solids flux. Solids circulation rates between 125 and 243 kg/(m2⋅s) were evaluated at a constant riser superficial gas velocity of 5.3 m/s. The effect of the riser superficial gas velocity of the local upflow at the riser centerline was also conducted at a solids circulation rate of 187 kg/(m2⋅s). The results show that there is little variation in the local net solids flux at radial locations between 0.00 ¡Ü r/R ¡Ü 0.87. The results indicate that a sharp regime change from a typical parabolic solids flux profile to this more radially uniform solids flux profile occurs at a gas velocity between 4.8 and 4.9 m/s.<p> To quantify stripping efficiency, the underflow of an injected tracer into the standpipe must be known. Quantification of the underflow into the standpipe requires knowledge of two main variables: the interstitial gas velocity and the tracer gas concentration profiles in the standpipe. Stripping efficiency was determined for stripper solids circulation rates of 44, 60, and 74 kg/(m2⋅s) and gas velocities of 0.1, 0.2, and 0.3 m/s. For most conditions studied, the interstitial gas velocity profile was found to be flat for both fluidized and packed bed flow. The stripping efficiency was found to be sensitive to the operating conditions. The highest efficiency is attained at low solids circulation rates and high stripping gas velocities.<p> In the numeric study, stripper hydrodynamics were examined for similar operating conditions as those used in the experimental program. Due to an improved radial distribution of gas and decreasing bubble rise velocity, mass transfer is deemed most intense as bubbles crest above the baffles into the interspace between disc and donut baffles. Stripping efficiency is thought to improve with increasing gas velocity due to an increased bubbling frequency. Stripping efficiency is thought to decrease with increasing solids circulation rates due to a lower emulsion-cloud gas interchange coefficient and a decreased residence time of the emulsion in the stripper.
17

Experimental and modeling study of a cold-flow fluid catalytic cracking unit stripper

Wiens, Jason Samuel 22 June 2010 (has links)
Many particulate processes are preferably implemented in circulating fluidized beds (CFB) over traditional low-velocity fluidization to take advantage of the many benefits of circulating systems. Fluid catalytic cracking (FCC) is one of the most successfully applied processes in CFB technology, with more than 350 FCC units in operation worldwide. Despite its extensive use, an understanding of the complex behaviour of these units is incomplete.<p> A theoretical and experimental evaluation of the fluidization behaviour was conducted in the CFB riser, standpipe, and stripper. Initially, an extension of the existing CFB in the Fluidization Laboratory of Saskatchewan was designed. The experimental program conducted in this study included an examination of the solids flow behaviour in the riser, interstitial gas velocity in the downcomer, and stripping efficiency measurements. The hydrodynamic behaviour of the stripper was modeled using Multiphase Flow with Interphase eXchanges (MFIX) CFD code.<p> The solids flow behaviour in the bottom zone of a high-density riser was investigated by measuring the local upwards and downwards solids flux. Solids circulation rates between 125 and 243 kg/(m2⋅s) were evaluated at a constant riser superficial gas velocity of 5.3 m/s. The effect of the riser superficial gas velocity of the local upflow at the riser centerline was also conducted at a solids circulation rate of 187 kg/(m2⋅s). The results show that there is little variation in the local net solids flux at radial locations between 0.00 ¡Ü r/R ¡Ü 0.87. The results indicate that a sharp regime change from a typical parabolic solids flux profile to this more radially uniform solids flux profile occurs at a gas velocity between 4.8 and 4.9 m/s.<p> To quantify stripping efficiency, the underflow of an injected tracer into the standpipe must be known. Quantification of the underflow into the standpipe requires knowledge of two main variables: the interstitial gas velocity and the tracer gas concentration profiles in the standpipe. Stripping efficiency was determined for stripper solids circulation rates of 44, 60, and 74 kg/(m2⋅s) and gas velocities of 0.1, 0.2, and 0.3 m/s. For most conditions studied, the interstitial gas velocity profile was found to be flat for both fluidized and packed bed flow. The stripping efficiency was found to be sensitive to the operating conditions. The highest efficiency is attained at low solids circulation rates and high stripping gas velocities.<p> In the numeric study, stripper hydrodynamics were examined for similar operating conditions as those used in the experimental program. Due to an improved radial distribution of gas and decreasing bubble rise velocity, mass transfer is deemed most intense as bubbles crest above the baffles into the interspace between disc and donut baffles. Stripping efficiency is thought to improve with increasing gas velocity due to an increased bubbling frequency. Stripping efficiency is thought to decrease with increasing solids circulation rates due to a lower emulsion-cloud gas interchange coefficient and a decreased residence time of the emulsion in the stripper.
18

Modelagem e controle de unidades de craqueamento catalitico - FCC / Modeling and control of catalytic cracking units - FCCU

Ribeiro, Pleycienne Trajano 23 February 2007 (has links)
Orientador: Rubens Maciel Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-10T14:16:29Z (GMT). No. of bitstreams: 1 Ribeiro_PleycienneTrajano_M.pdf: 6676447 bytes, checksum: 6c29c9cac1ca3769c0c23d1c86851348 (MD5) Previous issue date: 2007 / Resumo: Por representar um importante processo de conversão da indústria petroquímica, o craqueamento catalítico é um dos processos de conversão mais estudados. Nele, moléculas de alto peso molecular são quebradas em moléculas com menor peso molecular, obtendo-se assim produtos economicamente mais desejáveis. Os estudos do processo, de sua modelagem matemática e dos seus sistemas de controle, podem garantir o conhecimento necessário para alcançar condições operacionais ótimas que levem à máxima conversão da carga. Neste contexto, este trabalho teve como objetivos: a pesquisa e utilização de uma modelagem matemática para o conversor FCC (Fluid Catalytic Cracking); o estudo do processo sob influência de um controlador PID clássico, muito utilizado em refinarias; a estruturação de uma rede neural artificial (RNA) e o seu posterior uso como modelo interno de um controlador avançado tipo preditivo desenvolvido a partir dos estudos feitos no processo de craqueamento catalítico. Em paralelo, foi cirada uma ferramenta de simulação que possibilitou o meio mais amigável e prático para realização de todas as simulações necessárias para o desenvolvimento do presente trabalho. O FCCGUI (Fluid Catalytic Cracking Graphical User Interface), nome dado ao simulador, proporciona a escolha de parâmetros de simulação, diferentes estruturas de controle (PID, DMC e MPC - baseado em redes neurais), a visualização de diferentes variáveis manipuladas, controladas e sinais de válvulas e facilidades para perturbar o sistema. Através das simulações foi possível acompanhar o comportamento das variáveis de processo em diferentes condições testadas, realizar a estruturação da rede neural e obter as respostas das variáveis controladas para os dois tipos de controladores estudados. Os resultados obtidos foram bastante satisfatórios, visto que a modelagem matemática escolhida representa bem o sistema e o controlador MPC-Neural desenvolvido se mostrou eficiente, por conseguir manter o processo estável e próximo ao set point, mesmo após a aplicação de perturbações no processo / Abstract: Catalytic cracking is one of the most studied conversion processes due its importance in the petrochemical industry. In this process high weight molecules are broken into lighter ones, yielding more economically valuable products. The study about the process, its mathematical modeling, and its control systems may guarantee the necessary knowledge needed to reach optimal operational conditions which lead to maximum load conversion. In this context, the present work thesis has as main objectives the research and use of a mathematical modeling for a FCC (Fluid Catalytic Cracking) conversion unit, the study of the system under PID control loop widely used in refineries, structuring of an artificial neural network (ANN) with its use as an internal model of a predictive control system developed for catalytic cracking. Parallel to this, it was developed a computational tool which in a friendly and practical way made possible to carry out simulations needed to accomplish this work. FCCGUI (Fluid Catalytic Cracking Graphical User Interface), name given to this simulator, allows to choose simulation parameters, different control systems (PID, DMC, and MPC-ANN Based), graphical visualization of many different variables, such as manipulated and controlled variables plus valve signals, also it allows for and easy means for disturbing the system while the simulation continues. Through the simulations it was possible to follow the behavior of many process variables under different tested operational conditions, to structure the neural network, and to obtain controlled variables responses for both types of control systems studied. The obtained results were quite satisfactory since the chosen mathematical modeling represents well the system and the developed MPC-ANN controller showed to be efficient to maintain the process stable and close to the set points even after the introduction of disturbances in the process. Taking all these into account, compared to PID controller, MPC-ANN showed to be less oscillatory and to be more effective / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química
19

Estudo do efeito da radiação ionizante na utilização dos catalisadores desativados de craqueamento / Study of the effect of ionizing radiation for utilization of spent cracking catalysts

KONDO, FERNANDO M. 23 February 2015 (has links)
Submitted by Maria Eneide de Souza Araujo (mearaujo@ipen.br) on 2015-02-23T19:40:28Z No. of bitstreams: 0 / Made available in DSpace on 2015-02-23T19:40:28Z (GMT). No. of bitstreams: 0 / Catalisador é uma substância que altera a velocidade de uma reação. Na indústria do petróleo os catalisadores mais utilizados são os catalisadores de Fluid Catalytic Cracking (FCC) e Hidrocatalytic Cracking (HCC) cada qual utilizado em uma determinada etapa do processo. Esses catalisadores são usados para facilitar a quebra das cadeias moleculares que darão origem a uma mistura de hidrocarbonetos. Contudo, o catalisador perde progressivamente sua atividade, seja pela mudança de sua estrutura molecular original ou pela sua contaminação provenientes de outras moléculas do petróleo. A aplicação das radiações ionizantes (feixe de elétrons e raios gama) nesses catalisadores desativados foi estudada para auxiliar na extração de metais ou terras-raras de alto valor agregado. Nos ensaios realizados com os catalisadores de FCC utilizaram-se das técnicas de irradiação por 60Co e por feixe de elétrons (EB) e tiveram como estudo a extração do lantânio (La2O3), a regeneração e utilização desses catalisadores. Entretanto, o uso da radiação ionizante não contribuiu nesses processos. Já nos catalisadores de HCC foi utilizado a irradiação por feixe de elétrons e como estudo a extração do molibdênio (MoO3). Na temperatura em torno de 750°C nesses catalisadores irradiados do leito inferior obteve-se um rendimento de extração duas vezes maior em comparação aos não irradiados, ou seja de 57,65% e 26,24% respectivamente. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
20

Avaliação e aplicação dos resultados da curva PEV estendida em sistemas de processamento e refino de frações pesadas de petroleo / Evaluation and application of the extended TBP curves in processing and refining of heavy oil fractions

Cuadros Bohórquez, José Fernando 12 August 2018 (has links)
Orientador: Rubens Maciel Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-12T16:03:46Z (GMT). No. of bitstreams: 1 CuadrosBohorquez_JoseFernando_M.pdf: 955377 bytes, checksum: 373ed9ca95fec71c8fc315f656b0a361 (MD5) Previous issue date: 2008 / Resumo: A extração de petróleo no Brasil produz, em grande parte, petróleos pesados. Este tipo de óleo é de difícil processamento e gera grande quantidade de resíduos provenientes das torres de destilação atmosférica e de vácuo. É necessário fracionar esse tipo de petróleo pesado, com a finalidade de incrementar a produção de frações leves, principalmente o Diesel. A caracterização do petróleo é feita mediante as curvas PEV (Ponto de Ebulição Verdadeiro), através das normas padronizadas ASTM (American Society fot Testing and Materials); porém, a curva de destilação só pode ser obtida mediante as normas ASTM até 565ºC. Uma extensão acima dessa temperatura limite, 565ºC, foi desenvolvida pelo grupo de pesquisa do Laboratório de Desenvolvimento de Processos de Separação (LDPS) e do Laboratório de Otimização, Projeto e Controle Avançado (LOPCA), da Faculdade de Engenharia Química da Universidade Estadual de Campinas (FEQ/ UNICAMP), como apresentado em diversos trabalhos prévios (SBAITE, 2005). A metodologia desta extensão envolve o processo de Destilação Molecular, tornando possível a caracterização de frações pesadas de petróleo acima de 565ºC. A caracterização feita com a extensão da curva PEV (nova curva PEV ou DESTMOL) foi usada nesta dissertação que fez uso do simulador de processos Hysys.Plant®, mediante a geração de pseudocomponentes, para fazer a caracterização da alimentação do sistema no processo de refino. Nesta dissertação, foi desenvolvida uma metodologia de simulação para avaliar as curvas PEV estendidas no esquema de separação após o reator de FCC (Fluid Catalytic Cracking). Nesta unidade, são obtidos diferentes produtos: GLP (Gás Liquefeito de Petróleo), gasolina e diesel. O esquema de separação e um processo complexo, incluindo diferentes correntes de reciclo. Os resultados das simulações de dois tipos de resíduos de petróleo foram comparados com dados industriais, obtendo-se bons resultados. Deste trabalho, foi possível concluir que a avaliação das curvas PEV no sistema de separação após o FCC, depende das condições de projeto e de operação desta unidade, uma vez que para valores da curva PEV na alimentação acima de 550ºC, não ocorre a vaporização de alimentações com óleos mais leves, afetando significativamente a operação da unidade. Depois de fazer comparações entre os dados industriais e os dados da simulação, pode-se concluir que a avaliação deste tipo de análise (Curva PEV estendida) deveria ser feita em outro tipo de unidade, por exemplo o riser de FCC, pois este tem a capacidade de processar frações pesadas de petróleo, que é o que esta sendo representado mediante a curva PEV estendida, em frações mais leves como: gases combustíveis, GLP e nafta de craqueamento, obtidas após sua separação na unidade de fracionamento e recuperação de produtos. / Abstract: The oil extraction in Brazil is predominantly of heavy oil. This type of oil is difficult to process and it produces great quantity of residues from atmospheric and vacuum columns. It is necessary to upgrade such kind of residues in order to increase productivity of light fractions, mainly diesel. Oil characterization is made with the aid of the True Boiling Point (TBP) curve through ASTM standard test methods; however, it is possible to have this curve only until 565 ºC. An extension beyond this temperature limit was developed by this research group and it is presented in previous works in the literature, (SBAITE, 2005). For such purpose, molecular distillation process was used, which uses high vacuum as separating agent. In this sense, extension of the True Boiling Point (TBP) curve was obtained using the molecular distillation process, making possible the characterization of the heavy oil fractions of TBP higher than 565ºC. The characterization made with the extension of the TBP was used in this work in the process simulator Hysys.Plant® by the generation of pseudocomponents for characterizing the systems feeding distillation columns in the refining process. In this work, it was developed a simulation methodology in order to evaluate all the separation sequencing after the FCC (Fluid Catalytic Cracking) reactor, in order to produce different products, like (LPG), gasoline and diesel. A complex configuration characterizes this step of the refining process, including several recycle streams. The simulation results of two types of petroleum residues, Alpha 565C+ and Gamma 545C+ were compared with industrial data, yielding, very good match. From this work, it was possible to conclude that the evaluation of the TBP curves in the FCC separation steps depends on the design conditions of this unit, considering that feed at fractionation temperature above 550 ºC remains in liquid state affecting significantly the fractionator tower operation. These results are new in the open literature. After the comparisons between industrial and simulation results, can be concluded that the evaluation of this type heavy oil analysis should be performed in another unit capable to convert these products, called heavy gasoil in noble products, which can be used in the downstream FCC. This conversion process can be performed in the FCC riser. / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química

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