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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

Análise e Otimização da Produção de Hidrocarbonetos Líquidos Via a Reação de Fischer Tropsch Por Meio da Tecnologia Gas To Liquid (GTL).

Lira, Rodrigo Lucas Tenorio Calazans de 31 May 2012 (has links)
Submitted by Eduarda Figueiredo (eduarda.ffigueiredo@ufpe.br) on 2015-03-11T14:35:25Z No. of bitstreams: 2 Dissertação Completa_Rodrigo.pdf: 2042384 bytes, checksum: adeaba5f9e93bef7dcc818744781565e (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-11T14:35:25Z (GMT). No. of bitstreams: 2 Dissertação Completa_Rodrigo.pdf: 2042384 bytes, checksum: adeaba5f9e93bef7dcc818744781565e (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2012-05-31 / A tecnologia de produção de combustíveis sintéticos iniciou seu desenvolvimento a partir de 1919, na Alemanha, tendo o carvão mineral como insumo para a gaseificação. Com o passar dos anos novos insumos foram utilizados, como a biomassa e o gás natural, cada um com rotas tecnológicas próprias. Com o uso do gás natural esta rota tecnológica é conhecida como Gas-To- Liquids (GTL) sendo uma transformação química que gera faixas de hidrocarbonetos líquidos e estáveis à temperatura e pressão ambientes. Este processo tem como etapa principal etapa à reação de Fischer Tropsch (FT), pois transforma gás síntese resultante da reforma do gás natural em hidrocarbonetos líquidos que ao serem refinados tornamse importantes produtos para indústria petroquímica, de transporte e áreas afins. Essa transformação pode ser realizada no próprio local de produção do gás, evitando investimentos e problemas ambientais na construção de gasodutos. No Brasil, o gás natural apresenta crescente incremento da sua produção, e forte aumento das suas reservas, como por exemplo, a descoberta do pré-sal e o gás natural presente pode estar tanto associado quanto não-associado ao petróleo. Devido às estruturas de plataformas normalmente se localizarem em áreas remotas, torna-se custoso o aproveitamento desse gás que é liberado pela produção do óleo, sendo o mesmo queimado ou ventado. Devido às restrições estabelecidas pela legislação ambiental, a queima do gás natural nas plataformas de produção passa a ser problemática e crítica. Este trabalho teve como objetivo desenvolver e avaliar por meio de simulação computacional uma planta de GTL na produção de hidrocarbonetos líquidos via a reação de FT e utilizá-lo na otimização do processo, na busca por um processo com maior capacidade produtiva e com menores gastos energéticos, gerando um melhor aproveitamento do gás natural, produzindo materiais com maior valor agregado. Foram utilizados os softwares de simulação MATLAB® e HYSYS®, que permitiram a analise de resultados satisfatórios para a conversão e distribuição de hidrocarbonetos gerados em comparação com o descrito pela literatura. A qualidade dos hidrocarbonetos gerados foi analisada pela avaliação do diesel obtido.
2

Process simulation and evaluation of ethane recovery process using Aspen-HYSYS

Rezakazemi, M., Rahmanian, Nejat, Jamil, Hassan, Shirazian, S. 12 March 2021 (has links)
Yes / In this work, the process of ethane recovery plant was simulated for the purpose of Front End Engineering Design. The main objective is to carry out a series of simulation using Aspen HYSYS to compare recovery of ethane from Joule Thomson (JT) Valve, Turbo-Expander and Twister Technology. Twister technology offers high efficiency, more ethane recovery and lower temperature than JT valve and turbo-expander process. It lies somewhere between isenthalpic and isentropic process due to its mechanical configuration. Three processes were compared in terms of recovery of ethane. To conduct the simulations, a real gas plant composition and design data were utilized to perform the study for comparison among chosen technologies which are available for ethane recovery. The same parameters were used for the comparisons. Effect of operating conditions including pressure, temperature, and flow rate as well as carbon dioxide on the recovery of ethane was examined.
3

Simulação de uma planta piloto de Biodisel com estudo da viabilidade econômica preliminar usando o ASPEN/HYSYS

Pinho Costa Souza, Thibério 31 January 2011 (has links)
Made available in DSpace on 2014-06-12T18:04:23Z (GMT). No. of bitstreams: 2 arquivo213_1.pdf: 4056030 bytes, checksum: c7d78e098b753c3c2b6ce96fc5f9588a (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Universidade Federal de Pernambuco / Nos últimos anos o biodiesel se tornou uma alternativa para a demanda crescente de combustível. O próximo passo é conseguir produzir um biodiesel economicamente competitivo com o diesel fóssil em um processo em nível industrial. Este trabalho visa estudar do ponto de vista computacional, uma planta piloto de biodiesel, simulando o processo desde a reação de transesterificação de óleos vegetais, chegando até a purificação do biodiesel, utilizando o APEN/HYSYS. Além disso, foi feito o estudo da viabilidade econômica preliminar da mesma, fazendo-se uso do custo anualizado total unitário CATU. Os resultados das simulações foram comparados com os resultados obtidos numa planta piloto montada em Pernambuco/Brasil. Em seguida, foi comparada a viabilidade econômica da planta piloto, com uma planta operando com uma coluna de destilação reativa para produção do referido combustível. Os resultados mostraram que a destilação reativa é um processo mais econômico para a produção do biodiesel do que em um processo em batelada
4

An investigation on hydrate prediction and inhibition: An industrial case study

Rahmanian, Nejat, Soyler, N., Wande, F.M., Hashemi, H. 02 September 2024 (has links)
Yes / This investigation reports the first study to predict natural gas hydrate formation using both Aspen HYSYS® and HydraFlash software for various gas compositions and thermodynamic inhibitors (monoethylene glycol [MEG] concentrations at 10, 20, 30, and 40 wt.% and methanol concentrations at 10 and 20 wt.%). The simulated predictions are compared with the results of the experimental data in the literature. It has been shown that HydraFlash software can accurately predict hydrate formation conditions for a given industrial case, without having to carry out costly experimental work. This work also evaluated the effect of inhibitors and it appears that inhibitor type and concentration are determined according to condition of gas composition. MEG is consequently selected as the most ideal hydrate inhibitor for the industrial case. This also was confirmed through COSMO-RS studies in which the sigma profile and sigma potential of the considered inhibitors were obtained and presented using density functional (DFT) calculations to verify the hydrogen bonding affinities of the inhibitors to water molecules. HydraFlash was utilized to predict the dissociation conditions of hydrates under the influence of a high concentration of MEG inhibition, reaching up to 40 wt.% at 313 K and a pressure of 311.1 bar. Finally, it is shown that both software packages are quite accurate and useful tools for the prediction of hydrate for simple systems. However, HydraFlash can simulate more complex systems, including different types of salts at higher pressures. Investigation results indicate insightful guidance for accurately predicting hydrate dissociation under simulated conditions. / The authors would also like to thank the Turkish National Agency for offering an Erasmus student grant for Mr. Nejmi Söyler under the Erasmus+ Program Action 1 throughout the training period.
5

Avaliação paramétrica de uma unidade de hidrotratamento de diesel

ALBUQUERQUE, Douglas Fernandes de 25 February 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-07-28T15:36:12Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação de mestrado - Douglas Fernandes de Albuquerque - Eng. Química UFPE.pdf: 3870346 bytes, checksum: 5761fe7b587741384858becbacc00121 (MD5) / Made available in DSpace on 2016-07-28T15:36:12Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação de mestrado - Douglas Fernandes de Albuquerque - Eng. Química UFPE.pdf: 3870346 bytes, checksum: 5761fe7b587741384858becbacc00121 (MD5) Previous issue date: 2016-02-25 / CAPEs / Devido à formulação de leis mais rigorosas com relação à preservação do meio ambiente, sobretudo no que diz respeito ao teor de enxofre presente nos combustíveis fósseis, as refinarias de todo o mundo estão sendo desafiadas a adequarem seus processos de refino a condições operacionais mais severas, que permita a produção dos derivados do petróleo de ultrabaixo teor de enxofre. Maior atenção é dada aos destilados intermediários, tais como a gasolina e o óleo diesel, por apresentaram vasta empregabilidade no setor de transporte, que é por sua vez o setor da economia que mais consome combustíveis fósseis. Sendo o derivado de petróleo mais consumido no setor de transportes e responsável por grande parcela da emissão de compostos tóxicos durante a queima em motores de combustão, o óleo diesel é hoje submetido a normas legais que limitam o teor de enxofre para 10 mg/kg, o que torna mais difícil o processamento do destilado, uma vez que o petróleo utilizado está cada vez mais pesado. Diante disso, no presente trabalho uma unidade de hidrotratamento de diesel oriundo de um petróleo pesado foi modelada e simulada em estado estacionário, utilizando o software Aspen HYSYS® como ferramenta computacional, sendo avaliados os principais parâmetros de processos e o desempenho da unidade frente a suas variações, com o objetivo de determinar condições de trabalho que garantissem uma produção de óleo diesel com no máximo 10 mg/kg de enxofre, obtendo simultaneamente um alto rendimento de produção. Inicialmente foram propostas algumas hipóteses e as condições operacionais da unidade com base em dados relatados na literatura. De acordo com as condições de trabalho empregadas, foi possível atingir um óleo diesel tratado com 3,55 mg/kg de enxofre, 3,21 mg/kg de nitrogênio e 0,03 mg/kg de água, alcançando uma recuperação de 81,00 m/m% dos compostos constituintes da faixa de destilação do óleo diesel presentes na carga da unidade. Em conjunto também foi analisado o gasto energético da unidade a fim de se obter uma estimativa da viabilidade econômica do processo, sendo constatado que as utilidades e as colunas conferem os maiores consumos de energia. Com base nas análises de sensibilidade realizadas, ainda foi possível estabelecer a relação entre os resultados analisados em cada seção da unidade e os parâmetros envolvidos no controle dos mesmos. E a partir das respostas obtidas, foi elaborada a otimização do processo a partir da Metodologia de Superfície de Resposta através do emprego do software Statistica, conferindo condições mais eficientes de trabalho, garantindo assim a produção de um óleo mais purificado, contendo cerca de 0,10 mg/kg de enxofre, com maior recuperação dos compostos do diesel (aproximadamente 85,11 m/m%), além de gerar menores gastos energéticos, alcançando uma redução de 16,54 % referente à simulação mantida nas condições padrão de trabalho. Em adição, no caso otimizado ainda foi possível atingir maiores valores de recuperação dos demais cortes de petróleo constituintes da alimentação da unidade. / Due to the development of stricter laws regarding the preservation of the environment, especially in relation to the sulfur content in fossil fuels, refineries around the world are being challenged to adapt their refining processes to more severe operating conditions, that they are able to product ultra-low sulfur petroleum distillates. Greater attention is given to intermediate distillates, such as gasoline and diesel oil, due to their extensive employment in the transport sector, which is the sector of the economy that consumes more fossil fuels. Diesel oil is the petroleum product most consumed in the transportation sector and accounts for a large portion of the emission of toxic compounds during combustion in engines, this way diesel is now subject to legal rules that limit the sulfur content to 10 mg/kg, which complicates the processing of the distillate, since the petroleum used is heavier. Therefore, in this paper a unit of diesel hydrotreating come from a heavy oil was modeled and simulated in steady state, using the Aspen HYSYS® software as computational tool, and the main process parameters and performance unit against their variations are evaluated, by purpose of determining working conditions that would ensure diesel production with a maximum of 10 mg/kg of sulfur, at the same time achieving a high production yield. Initially some hypotheses and unit operating conditions were proposed based on data reported in the literature. According to the working conditions employed, it was possible to achieve a diesel fuel treated with 3.55 mg/kg sulfur, 3.21 mg/kg nitrogen and 0.03 mg/kg water, obtaining 81.00 wt% recovery of constituent compounds of distillation range of diesel oil present in the unit load. Together it was also analyzed the energy expenditure of the unit in order to obtain an estimate of the economic viability of the process, and it was found out that the utilities and columns required the highest energy consumption. Based on the sensitivity analysis performed, it was still possible to establish the relationship between the results analyzed in each section of the unit and the parameters involved in their control. Since the answers were obtained, the optimization of the process through the Response Surface Methodology by using the Statistica software was developed, providing more efficient working conditions, thus ensuring the production of more purified oil, containing about 0.10 mg/kg of sulfur, with greater recovery of the compounds of diesel (about 85.11 wt%), besides generating lower energy costs, achieving a reduction of 16.54% referring to the simulation maintained in standard working conditions. In addition, the optimized case was still possible to achieve higher recovery value of other of petroleum distillates, which were constituents of the unit feed.
6

Steam consumption minimization using genetic algorithm optimization method: an industrial case study

Alabdulkarem, A., Rahmanian, Nejat 13 May 2020 (has links)
yes / Condensate stabilization is a process where hydrocarbon condensate recovered from natural gas reservoirs is processed to meet the required storage, transportation, and export specifications. The process involves stabilizing of hydrocarbon liquid by separation of light hydrocarbon such as methane from the heavier hydrocarbon constituents such as propane. An industrial scale back-up condensate stabilization unit was simulated using Aspen HYSYS software and validated with the plant data. The separation process consumes significant amount of energy in form of steam. The objectives of the paper are to find the minimum steam consumption of the process and conduct sensitivity and exergy analyses on the process. The minimum steam consumption was found using genetic algorithm optimization method for both winter and summer conditions. The optimization was carried out using MATLAB software coupled with Aspen HYSYS software. The optimization involves six design variables and four constraints, such that realistic results are achieved. The results of the optimization show that savings in steam consumption is 34% as compared to the baseline process while maintaining the desired specifications. The effect of natural gas feed temperature has been investigated. The results show that steam consumption is reduced by 46% when the natural gas feed temperature changes from 17.7 to 32.7°C. Exergy analysis shows that exergy destruction of the optimized process is 37% less than the baseline process.
7

Process simulation and assessment of a back-up condensate stabilization unit

Rahmanian, Nejat, Bin Ilias, I., Nasrifar, K. 06 July 2015 (has links)
Yes / A simulation was conducted using Aspen HYSYS® software for an industrial scale condensate stabilization unit and the results of the product composition from the simulation were compared with the plant data. The results were also compared to the results obtained using PRO/II software. The results show that the simulation is in good agreement with the plant data, especially for medium range hydrocarbons. For hydrocarbons lighter than C5, the simulation results over predict the plant data while for hydrocarbons heavier than C9 this trend is reversed. The influences of steam temperature and pressure, as well as feed conditions (flow rate, temperature and pressure) for the product specification (RVP and sulphur content) were also investigated. It was reported that the operating conditions gave rise to the production of off-specification condensate and it was also found that the unit could be utilized within 40–110% of its normal throughput without altering equipment sizing and by the operating parameters.
8

Development of molecular distillation based simulation and optimization of refined palm oil process based on response surface methodology

Tehlah, N., Kaewpradit, P., Mujtaba, Iqbal 16 July 2017 (has links)
Yes / The deodorization of the refined palm oil process is simulated here using ASPEN HYSYS. In the absence of a library molecular distillation (MD) process in ASPEN HYSYS, first, a single flash vessel is considered to represent a falling film MD process which is simulated for a binary system taken from the literature and the model predictions are compared with the published work based on ASPEN PLUS and DISMOL. Second, the developed MD process is extended to simulate the deodorization process. Parameter estimation technique is used to estimate the Antoine’s parameters based on literature data to calculate the pure component vapor pressure. The model predictions are then validated against the patented results of refining edible oil rich in natural carotenes and vitamin E and simulation results were found to be in good agreement, within a 2% error of the patented results. Third, Response Surface Methodology (RSM) is employed to develop non-linear second-order polynomial equations based model for the deodorization process and the effects of various operating parameters on the performance of the process are studied. Finally, an optimization framework is developed to maximize the concentration of beta-carotene, tocopherol and free fatty acid while optimizing the feed flow rate, temperature and pressure subject to process constrains. The optimum results of feed flow rate, temperature, and pressure were determined as 1291 kg/h, 147 C and 0.0007 kPa respectively, and the concentration responses of beta- carotene, tocopherol and free fatty acid were found to be 0.000575, 0.000937 and 0.999840 respectively. / Prince of Songkla University, Songkhla, Thailand for providing financial support (Grant code: PSU2554-022)
9

Simulation and Optimization of a Condensate Stabilization Process

Rahmanian, Nejat, Jusoh, L.S.B., Homayoonfard, M., Nasrifar, K., Moshfeghian, M. 08 April 2016 (has links)
Yes / A simulation was conducted using Aspen HYSYS® software for an industrial scale condensate stabilization unit and the results of the product composition from the simulation were compared with the plant data. The results were also compared to the results obtained using PRO/II software. It was found that the simulation is closely matched with the plant data and in particular for medium range hydrocarbons. The effects of four process conditions, i.e. feed flow rate, temperature, pressure and reboiler temperature on the product Reid Vapour Pressure (RVP) and sulphur content were also studied. The operating conditions which gave rise to the production of off-specification condensate were found. It was found that at a column pressure of 8.5 barg and reboiler temperature of 180°C, the condensate is successfully stabilised to a RVP of 60.6 kPa (8.78 psia). It is also found that as compared to the other parameters the reboiler temperature is the most influential parameter control the product properties. Among the all sulphur contents in the feed, nP-Mercaptan played a dominant role for the finishing product in terms of sulphur contents.
10

Ambiente de simula??o h?brido integrando hysys e rede industrial Foundation Fieldbus aplicado ao controle de uma coluna de destila??o

Costa, Bruno Xavier da 11 March 2011 (has links)
Made available in DSpace on 2014-12-17T14:55:51Z (GMT). No. of bitstreams: 1 BrunoXC_DISSERT.pdf: 1188084 bytes, checksum: 9f335fff2b0475dfa1b67655e6d44e2f (MD5) Previous issue date: 2011-03-11 / The main purpose of this work is to develop an environment that allows HYSYS R chemical process simulator communication with sensors and actuators from a Foundation Fieldbus industrial network. The environment is considered a hybrid resource since it has a real portion (industrial network) and a simulated one (process) with all measurement and control signals also real. It is possible to reproduce different industrial process dynamics without being required any physical network modification, enabling simulation of some situations that exist in a real industrial environment. This feature testifies the environment flexibility. In this work, a distillation column is simulated through HYSYS R with all its variables measured and controlled by Foundation Fieldbus devices / O principal objetivo deste trabalho ? desenvolver um ambiente que permite a comunica??o do simulador de processos qu?micos HYSYS R com medidores e atuadores de uma rede industrial Foundation Fieldbus. O ambiente ? considerado h?brido por possuir uma parte real (a rede industrial) e uma parte simulada (o processo) com os sinais de controle e medi??o sendo reais. O ambiente ? bastante flex?vel, permitindo a reprodu??o de diversas din?micas t?picas de processos industriais sem a necessidade de altera??o na rede f?sica, possibilitando gerar diversas situa??es existentes em um ambiente industrial real. No presente trabalho, a din?mica utilizada ? de uma coluna de destila??o, simulada no HYSYS R, com suas vari?veis medidas e controladas pelos dispositivos da rede industrial Foundation Fieldbus

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