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Modélisation des équilibres entre phases et simulation de la distillation des eaux-de-vie en vue d’une meilleure compréhension du comportement des composés volatils d’arôme / Modeling of phase equilibria and simulation of spirits distillation for a better understanding of volatile aroma compounds behavior.Puentes Mancipe, Cristian 13 December 2017 (has links)
La qualité des eaux-de-vie est un paramètre associé à la composition en composés volatils d’arôme. Cette composition résulte de la combinaison de différents facteurs dont la nature et le traitement des matières premières, mais surtout des transformations ayant lieu lors des phases de fermentation, distillation et, dans la plupart de cas, vieillissement.La distillation est une opération de séparation pratiquée depuis des millénaires, avec une technologie assez mature. Cependant, dans le domaine des eaux-de-vie, elle s’appuie essentiellement sur des connaissances empiriques. L’objectif de ce doctorat fut de contribuer à une meilleure compréhension du comportement des composés volatils d’arôme au cours de différents modes de distillation et de fournir des bases scientifiques à la conduite des unités par le biais de modules de simulation. L’attention a été portée sur la distillation d’Armagnac et de Calvados dans des colonnes multiétagées en régime stationnaire.Les modules de simulation ont été construits avec le logiciel ProSimPlus®. La première partie des travaux a été consacrée à l’acquisition de données d’équilibre liquide-vapeur des composés volatils d’arôme en milieu hydroalcoolique pour l’identification du modèle NRTL, en suivant trois approches complémentaires : recherche dans la littérature, détermination expérimentale et prédiction théorique avec les modèles UNIFAC et COSMO. Grâce à la connaissance acquise sur les volatilités relatives par rapport à l’éthanol et à l’eau, les composés volatils d’arôme ont pu être classés en trois groupes : composés légers, composés intermédiaires et composés lourds. La deuxième partie des travaux a porté sur la construction et la validation des modules de simulation, après réconciliation des données issues de la caractérisation expérimentale des unités de distillation. Cette investigation démontre que la simulation est un outil d’ingénierie performant dans le domaine des eaux-de-vie. Les résultats de la simulation ont permis d’affiner la classification des composés intermédiaires en trois catégories supplémentaires selon leur profil de concentration dans la colonne et leur taux de récupération dans le distillat. Enfin, cet outil a mis en évidence que certains paramètres opératoires, notamment l’augmentation de la teneur en éthanol du distillat ainsi que l’extraction de queues, favorisent la séparation préférentielle de certaines espèces de volatilité faible ou intermédiaire par rapport à l’éthanol. / The quality of spirits is a parameter related to the composition of volatile aroma compounds. This composition results from the combined production process of raw material extraction, subsequent fermentation, distillation and, in many cases, ageing.Distillation is a very old and the most important industrial separation technology. However, in spirits production, this operation relies essentially on empirical knowledge. The aim of this PhD was to contribute to a better understanding of the volatile aroma compounds behaviour in spirits distillation and to provide a scientific basis for the process through computer simulation. The study was focused on Armagnac and Calvados production by continuous multistage distillation.The simulation modules were built using the software ProSimPlus®. The first part of this research was dedicated to the acquisition of vapor-liquid equilibrium data of the volatile aroma compounds in ethanol-water solutions, in order to estimate the binary interaction parameters of the NRTL model.Three complementary approaches of data acquisition were used: literature compilation, experimental measurements and predictions with UNIFAC and COSMO models.According to their relative volatilities with respect to ethanol and water, the volatile aroma compounds can be classified in three groups: light compounds, intermediary compounds and heavy compounds. The second part of this research dealt with the creation and validation of simulation modules, by using reconciled experimental data from the distillation units. The results prove that simulation is a powerful tool in spirits distillation. The simulation data enables a more precise classification of the intermediary compounds in three categories, by considering their composition profiles in the distillation column and their recovery ratios from feed to distillate. Finally, the analysis of some operating parameters, including ethanol concentration in the distillate as well as tails extractions, demonstrates that the distillate composition can be modified by virtue of a selective separation of intermediary and heavy compounds with respect to ethanol.
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An adaptive modeling and simulation environment for combined-cycle data reconciliation and degradation estimation.Lin, TsungPo 26 June 2008 (has links)
Performance engineers face the major challenge in modeling and simulation for the after-market power system due to system degradation and measurement errors. Currently, the majority in power generation industries utilizes the deterministic data matching method to calibrate the model and cascade system degradation, which causes significant calibration uncertainty and also the risk of providing performance guarantees. In this research work, a maximum-likelihood based simultaneous data reconciliation and model calibration (SDRMC) is used for power system modeling and simulation. By replacing the current deterministic data matching with SDRMC one can reduce the calibration uncertainty and mitigate the error propagation to the performance simulation.
A modeling and simulation environment for a complex power system with certain degradation has been developed. In this environment multiple data sets are imported when carrying out simultaneous data reconciliation and model calibration. Calibration uncertainties are estimated through error analyses and populated to performance simulation by using principle of error propagation. System degradation is then quantified by performance comparison between the calibrated model and its expected new & clean status.
To mitigate smearing effects caused by gross errors, gross error detection (GED) is carried out in two stages. The first stage is a screening stage, in which serious gross errors are eliminated in advance. The GED techniques used in the screening stage are based on multivariate data analysis (MDA), including multivariate data visualization and principle component analysis (PCA). Subtle gross errors are treated at the second stage, in which the serial bias compensation or robust M-estimator is engaged. To achieve a better efficiency in the combined scheme of the least squares based data reconciliation and the GED technique based on hypotheses testing, the Levenberg-Marquardt (LM) algorithm is utilized as the optimizer.
To reduce the computation time and stabilize the problem solving for a complex power system such as a combined cycle power plant, meta-modeling using the response surface equation (RSE) and system/process decomposition are incorporated with the simultaneous scheme of SDRMC. The goal of this research work is to reduce the calibration uncertainties and, thus, the risks of providing performance guarantees arisen from uncertainties in performance simulation.
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[en] MASS BALANCE DATA RECONCILIATION OF THE URUCU- MANAUS GAS PIPELINE / [pt] RECONCILIAÇÃO DE DADOS DO BALANÇO DE MASSA NO GASODUTO URUCU-MANAUSGISELE DE OLIVEIRA BARRETO 06 May 2016 (has links)
[pt] Se por um lado à privatização do setor de energia, que induz acirrada
concorrência, tem estimulado a inovação tecnológica e a adoção de mecanismos
de incentivos à eficiência operacional, a regulação do mercado introduz
mecanismos de controle requerendo maior responsabilidade no uso consciente
da energia de sorte a assegurar a eficiência energética e a proteção ambiental.
Pressões de organizações ambientalistas internacionais e a crescente demanda
por energia explicam a tendência mundial pelo uso de combustíveis fósseis mais
limpos. O baixo nível de emissões e resíduos associados ao processo de
combustão de gás natural qualifica esta commodity energética como um
elemento estratégico para integrar a matriz energética de organizações e países
comprometidos com a sustentabilidade global. O impacto econômico associado à
medição de gás natural exige uma otimização do controle do balanço de massa
no sistema de entrega. A aplicação da Metodologia de Reconciliação de Dados
constitui o objetivo deste trabalho. A técnica provou ser uma ferramenta eficaz
para a avaliação do balanço de massa em um gasoduto durante o período de
operação associado ao transporte de gás natural. A natureza intrínseca do seu
algoritmo de cálculo, que leva em conta a redundância nas medições, qualifica a
metodologia para aumentar a confiabilidade da medição assim reduzindo a
incerteza individual associada a cada grandeza física capaz de interferir na
medição e identificar erros grosseiros. Fundamentado na avaliação metrológica
do balanço de massa de um gasoduto brasileiro, os resultados do estudo
permitem discutir a adequação da técnica proposta de reconciliação de dados.
Dentre as conclusões do trabalho, foi possível mostrar que o uso da técnica de
tratamento dos dados do gás não contado (unaccounted for gas) pode atingir
valores inferiores a 0,3 porcento, comparando-se, assim, à tolerância preconizada em
nível internacional. / [en] If on the one hand, privatization of the energy sector, which induces keen
competition, has stimulated technological innovation and the adoption of
incentive mechanisms for operational efficiency, regulation of the market
introduces control mechanisms requiring greater responsibility in the conscious
use of energy so as to ensure energy efficiency and environmental protection.
Pressure from international environmental organizations and the growing
demand for energy, explain the worldwide tendency for the use of cleaner fossil
fuels. The lower levels of emissions and residues associated with the combustion
process of natural gas classify this energy commodity as a strategic element to
enter into the energy matrix of organizations and countries committed to global
sustainability. The economic impact associated with the measurement of natural
gas, demands optimization in controlling the mass balance in the delivery
system. Application of the Data Reconciliation Methodology constitutes the
objective of this work. The technique proved to be an efficient tool for the
evaluation of the mass balance in a gas pipeline for the period of operation
associated with the transport of natural gas. The intrinsic nature of its calculation
algorithm, which takes into account the redundancy of measurements, qualifies
the methodology to increase the confidence of measurement, thereby reducing
the individual uncertainty associated with each physical volume capable of
interfering with the measurement and identify gross errors. Based on the
metrological evaluation of the mass balance of a Brazilian pipeline, the results
of the study enable discussion on the adequacy of the data reconciliation
technique proposed. Among the conclusions of the work, it was possible to
demonstrate that the use of the technique in treating the data of unaccounted for
gas, could achieve values lower than 0.3 percent, thereby comparable with the
tolerances advocated at international level.
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Reconciliação dinâmica de dados baseada em estimadores em uma malha de controle MPC / Dynamic data reconciliation based on estimators in a MPC control loopSilva, Guilherme Moura Afonso da 27 April 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The data reconciliation in process control is extremely important regarding the
industries because from this it is possible to obtain a greater efficiency in the
performance in industrial process control meshes aiming at a lower cost and a higher
quality of the product. In this work we approach data estimation techniques for the
implementation of an online dynamic data reconciliation system in order to reduce the
noise and the measurement uncertainties that are submitted in the process variables. The
techniques used here are: the Kalman Filter, the Preditor-Corrector DDR Algorithm, the
Moving Horizon Estimator (MHE) and the Constrained Extended Kalman Filter
(CEKF). The analysis is performed by applying the dynamic data reconciliation system
in a simulated process, characteristic of the chemical industry, operating under MPC
(Model Predictive Control). The performance of the MPC controller is also enhanced by
the use of the reconciled data in the feedback control loop. / A reconciliação de dados em controle de processos é extremamente importante no que
diz respeito às indústrias, pois a partir dessa é possível obter uma maior eficiência no
desempenho em malhas de controle de processos industriais visando à minimização dos
custos e maximizando a qualidade do produto. Neste trabalho abordam-se técnicas de
estimação de dados para a implementação de um sistema de reconciliação dinâmica de
dados on-line a fim de reduzir os ruídos e as incertezas de medições a que estão
submetidas às variáveis do processo. As técnicas aqui empregadas são: o Filtro de
Kalman, o Algoritmo DDR Preditor-Corretor, o Estimador de Horizonte Móvel (MHE)
e o Filtro de Kalman Estendido com Restrições (CEKF). As análises são efetuadas
aplicando o sistema de reconciliação dinâmica de dados em um processo simulado,
característico da indústria química, operando sob controle preditivo (MPC). Também é
efetuado o aprimoramento no desempenho do controlador MPC utilizando os dados
reconciliados na malha de realimentação do controlador.
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Aplikace pokročilých regresních modelů / ADVANCED REGRESSION MODELSRosecký, Martin January 2018 (has links)
This thesis summarizes latest findings about municipal solid waste (MSW) modelling. These are used to solve multivariable version of inverse prediction problem. It is not possible to solve such problem analytically, so heuristic framework using regression models and data reconciliation was developed. As a side product, models for MSW modelling using PCA (Principal Component Analysis) and LM (Linear Model) were created. These were compared with heuristic model called RF (Random Forest). Both of these models were also used for per capita MSW modelling. Theoretical parts about generalized linear models, data reconciliation and nonlinear programming are also included.
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Vyrovnání provozních dat v energetických procesech / Data reconciliation of energy processesNováček, Adam January 2015 (has links)
This thesis is focused on problem data reconciliation of measurements. The objective of this thesis was reconciled measured value from electric drum dryer to suit exactly to the mathematical model of drying. For solution was used nonlinear data reconciliation with constrained nonlinear optimization. The entire calculation is processed in programme MATLAB and outputs are graphs of reconciled values of measurement on dryer such as inlet and outlet temperature and humidity, differential pressure of exhaust moisture air, weight of laundry, atmospheric pressure and electric supply. Achieved solution can by characterized by an amount of evaporated water. Weight of wet and dry laundry are 27,7 kg a 17,7 kg. The calculated amount of evaporated water from measurements was almost 18,8 kg. With reconciled measurements it was 9,7 kg. Goals of the thesis were found more realistic values.
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[en] DATA RECONCILIATION AND GUARD BANDS APPLIED TO THE ESTABLISHMENT OF SULFUR LIMITS IN FUELS FOCUSING ON MEETING SPECIFICATIONS / [pt] RECONCILIAÇÃO DE DADOS E BANDAS DE GUARDA APLICADAS AO ESTABELECIMENTO DE LIMITES DE ENXOFRE EM COMBUSTÍVEIS COM FOCO NO CUMPRIMENTO DAS ESPECIFICAÇÕESANA CAROLINA HERMOGENES DE MATOS 12 January 2023 (has links)
[pt] É uma prática operacional comum que as refinarias trabalhem de forma
otimizada e produzam diesel e gasolina com fração mássica de enxofre conforme
o limite da especificação. No entanto, quando esse parâmetro de qualidade é
analisado pelas refinarias e, após as operações de transferência, é reanalisado
pelos terminais de armazenamento, esses resultados de medição nem sempre
atendem à especificação. Para evitar disputa entre produtores e consumidores
sobre o cumprimento da especificação é necessário que haja uma margem mais
segura dentro da avaliação da conformidade desses produtos. Este trabalho
apresentou uma nova metodologia que utiliza da Reconciliação de Dados em
conjunto com o conceitos de bandas de guarda para determinação de novos
limites de tolerância de propriedades críticas, como o enxofre, em alguns
combustíveis, com base na reprodutibilidade, na diferença entre as médias de
todos os resultados aceitáveis de cada laboratório e nas especificações brasileiras.
Essa abordagem alternativa pode ser utilizada para evitar disputas entre
fornecedores e clientes (Oliveira e Aguiar, 2019). Em conjunto com a RD foram
utilizados os conceitos de regras de decisão com as definições das bandas de
guarda, apresentados pelo Guia Eurachem/CITAC, 2021. Na presente pesquisa,
foi visto que utilizando restrições de processo e medições redundantes, o valor
reconciliado (resultado final) apresenta melhores valores experimentais, além
disso a incerteza reconciliada é minimizada em relação às incertezas que foram
calculadas experimentalmente. / [en] It is an operational practice that refineries (here producers) work in an
optimized way and produce diesel and gasoline with a mass fraction of sulfur
close to the specification. However, when this quality parameter is analyzed by
refineries and, later, after custody transfer operations, it is re-analyzed by storage
terminals (here called consumers), these measurement results do not always meet
the specification. This study proposes a new methodology based on data
reconciliation connected to the guard bands concept to establish upper acceptance
limits for producers offering a comfortable giveaway to consumers. From the
minimized reconciled expanded uncertainties, process model constraints, and the
upper specification limits, the upper acceptance limits for the producers were
optimized to ensure that the reconciled values meet the specification. Consumer
and producer risks and histograms were calculated. Validation data sets proved
that the proposed methodology could be applied because all the reconciled values
comply with the specifications.
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