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Freire, Luziany Adyja Da Costa - One of the best experts on this subject based on the ideXlab platform.

  • Montagem e operação de um secador pneumático tipo flash
    Universidade Federal do Rio Grande do Norte, 2014
    Co-Authors: Freire, Luziany Adyja Da Costa
    Abstract:

    Este trabalho tem como objetivo principal à concepção, montagem e operação de um secador pneumático do tipo flash com o propósito de avaliar novas configurações de secadores, apresentando uma importância regional no contexto da produção agrícola de grãos. O equipamento operou com temperaturas na ordem de 80°C e velocidade do ar de secagem igual a 35 m/s. Para este tipo de secador recomenda-se temperaturas superiores a 200°C e velocidades com alta pressão dinâmica. O equipamento operou com um bom desempenho na secagem do milho e arroz. Para efeito comparativo, também foi utilizado um secador de bandejas para secagem do milho e do arroz com casca em condições operacionais similares as praticadas com secador pneumático do tipo flash. Os resultados experimentais demonstraram que na secagem do milho ambos secadores responderam com desempenho análogo no que ser refere à taxa de secagem. Já na secagem do arroz com casca, o secador pneumático apresentou um desempenho superior ao secador de bandejas. Portanto, a partir dos dados experimentais as curvas para a secagem do milho foram melhor correlacionadas com o modelo de Lewis, enquanto que as curvas de secagem do arroz com casca foram melhor ajustadas com o modelo de Page. Assim, pode-se concluir que a configuração montada apresenta aspectos promissores que podem ser estudados utilizando-se materiais com diferentes características e em diferentescondições operacionaisIn this work, a pneumatic dryer has been designed and assembled in laboratory scale in order to study and evaluate configurations more efficient for application in drying of important materials of Northeast region in Brazil. The equipment was tested with drying of corn and rice grains, in conditions of temperature and air velocity at 80 oC and 35 m/s, respectively. For this type of dryer, it is recommended to work at temperatures above 200 °C and air velocity with higher dynamic pressure. However, even under operating conditions below what it is recommended, the results obtained with the pneumatic dryer were satisfactory. In addition, experiments of drying were performed by using a cabinet dryer (Batch dryer) under the same conditions used in the pneumatic dryer. Flash one curves for the corn were fitted satisfactorily by applying of the Lewis model, while a better agreement was found for rice by using the Page model. The data obtained with both drying processes allowed to compare the performance between pneumatic and Batch Dryers. In respect to drying rate, the pneumatic dryer presented a similar performance to the Batch dryer during processing with corn and a superior performance to the last one during processing with rice. Therefore, it was possible to verify that the pneumatic dryer assembled in this preliminar study can be applied for different materials and under different operating condition

  • Montagem e operação de um secador pneumático tipo flash
    Pesquisa e Desenvolvimento de Tecnologias Regionais, 2011
    Co-Authors: Freire, Luziany Adyja Da Costa
    Abstract:

    In this work, a pneumatic dryer has been designed and assembled in laboratory scale in order to study and evaluate configurations more efficient for application in drying of important materials of Northeast region in Brazil. The equipment was tested with drying of corn and rice grains, in conditions of temperature and air velocity at 80 oC and 35 m/s, respectively. For this type of dryer, it is recommended to work at temperatures above 200 °C and air velocity with higher dynamic pressure. However, even under operating conditions below what it is recommended, the results obtained with the pneumatic dryer were satisfactory. In addition, experiments of drying were performed by using a cabinet dryer (Batch dryer) under the same conditions used in the pneumatic dryer. Flash one curves for the corn were fitted satisfactorily by applying of the Lewis model, while a better agreement was found for rice by using the Page model. The data obtained with both drying processes allowed to compare the performance between pneumatic and Batch Dryers. In respect to drying rate, the pneumatic dryer presented a similar performance to the Batch dryer during processing with corn and a superior performance to the last one during processing with rice. Therefore, it was possible to verify that the pneumatic dryer assembled in this preliminar study can be applied for different materials and under different operating conditionsConselho Nacional de Desenvolvimento Científico e TecnológicoEste trabalho tem como objetivo principal à concepção, montagem e operação de um secador pneumático do tipo flash com o propósito de avaliar novas configurações de secadores, apresentando uma importância regional no contexto da produção agrícola de grãos. O equipamento operou com temperaturas na ordem de 80°C e velocidade do ar de secagem igual a 35 m/s. Para este tipo de secador recomenda-se temperaturas superiores a 200°C e velocidades com alta pressão dinâmica. O equipamento operou com um bom desempenho na secagem do milho e arroz. Para efeito comparativo, também foi utilizado um secador de bandejas para secagem do milho e do arroz com casca em condições operacionais similares as praticadas com secador pneumático do tipo flash. Os resultados experimentais demonstraram que na secagem do milho ambos secadores responderam com desempenho análogo no que ser refere à taxa de secagem. Já na secagem do arroz com casca, o secador pneumático apresentou um desempenho superior ao secador de bandejas. Portanto, a partir dos dados experimentais as curvas para a secagem do milho foram melhor correlacionadas com o modelo de Lewis, enquanto que as curvas de secagem do arroz com casca foram melhor ajustadas com o modelo de Page. Assim, pode-se concluir que a configuração montada apresenta aspectos promissores que podem ser estudados utilizando-se materiais com diferentes características e em diferentescondições operacionai

Guillermo H. Crapiste - One of the best experts on this subject based on the ideXlab platform.

  • Modeling of Batch Dryers for Shrinkable Biological Materials
    Food and Bioprocess Technology, 2009
    Co-Authors: Cristina Ratti, Guillermo H. Crapiste
    Abstract:

    Design of Dryers for biological materials is a complex problem, since in order to solve the model equations, foodstuff physicochemical and equilibrium properties and drying kinetics should be included as a function of water content and operating variables. Shrinkage of biological materials under dehydration must also be taken into account when the macroscopic balances in the bed of drying need to be solved. The main objective of this work was thus to develop a realistic simulation model to predict Batch deep bed drying of shrinkable biological materials. Differential macroscopic balances for heat and mass transfer in the air and solid phases were expressed in moving coordinates in order to solve the problem of particle shrinkage during drying. The equation system was solved by the ‘method of lines’ using the Gear package for temporal derivatives and finite differences for spatial ones. All the parameters and physical properties required to solve the model were taken from literature or determined independently in lab-scale experiments. A pilot-scale hot air Batch dryer was built in order to carry out experimental determinations during drying of slices or cylinders of potato, apple, and carrot at diverse hot air conditions. The appropriate choice of numerical method and initial conditions gave a reliable and stable solution of the equation system. The simulation results agreed closely to experimental data on deep bed Batch drying of food particles under different conditions. The use of variable porosity and volume due to shrinkage during drying improved notably the predictions of the simulation model.

Cristina Ratti - One of the best experts on this subject based on the ideXlab platform.

  • Modeling of Batch Dryers for Shrinkable Biological Materials
    Food and Bioprocess Technology, 2009
    Co-Authors: Cristina Ratti, Guillermo H. Crapiste
    Abstract:

    Design of Dryers for biological materials is a complex problem, since in order to solve the model equations, foodstuff physicochemical and equilibrium properties and drying kinetics should be included as a function of water content and operating variables. Shrinkage of biological materials under dehydration must also be taken into account when the macroscopic balances in the bed of drying need to be solved. The main objective of this work was thus to develop a realistic simulation model to predict Batch deep bed drying of shrinkable biological materials. Differential macroscopic balances for heat and mass transfer in the air and solid phases were expressed in moving coordinates in order to solve the problem of particle shrinkage during drying. The equation system was solved by the ‘method of lines’ using the Gear package for temporal derivatives and finite differences for spatial ones. All the parameters and physical properties required to solve the model were taken from literature or determined independently in lab-scale experiments. A pilot-scale hot air Batch dryer was built in order to carry out experimental determinations during drying of slices or cylinders of potato, apple, and carrot at diverse hot air conditions. The appropriate choice of numerical method and initial conditions gave a reliable and stable solution of the equation system. The simulation results agreed closely to experimental data on deep bed Batch drying of food particles under different conditions. The use of variable porosity and volume due to shrinkage during drying improved notably the predictions of the simulation model.

Crapiste, Guillermo Hector - One of the best experts on this subject based on the ideXlab platform.

  • Modeling of Batch Dryers for Shrinkable Biological Materials
    'Springer Science and Business Media LLC', 2009
    Co-Authors: Ratti Cristina, Crapiste, Guillermo Hector
    Abstract:

    Design of Dryers for biological materials is a complex problem, since in order to solve the model equations, foodstuff physicochemical and equilibrium properties and drying kinetics should be included as a function of water content and operating variables. Shrinkage of biological materials under dehydration must also be taken into account when the macroscopic balances in the bed of drying need to be solved. The main objective of this work was thus to develop a realistic simulation model to predict Batch deep bed drying of shrinkable biological materials. Differential macroscopic balances for heat and mass transfer in the air and solid phases were expressed in moving coordinates in order to solve the problem of particle shrinkage during drying. The equation system was solved by the ‘method of lines’ using the Gear package for temporal derivatives and finite differences for spatial ones. All the parameters and physical properties required to solve the model were taken from literature or determined independently in lab-scale experiments. A pilot-scale hot air Batch dryer was built in order to carry out experimental determinations during drying of slices or cylinders of potato, apple, and carrot at diverse hot air conditions. The appropriate choice of numerical method and initial conditions gave a reliable and stable solution of the equation system. The simulation results agreed closely to experimental data on deep bed Batch drying of food particles under different conditions. The use of variable porosity and volume due to shrinkage during drying improved notably the predictions of the simulation model.Fil: Ratti, Cristina. Laval University; CanadáFil: Crapiste, Guillermo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentin

Ratti Cristina - One of the best experts on this subject based on the ideXlab platform.

  • Modeling of Batch Dryers for Shrinkable Biological Materials
    'Springer Science and Business Media LLC', 2009
    Co-Authors: Ratti Cristina, Crapiste, Guillermo Hector
    Abstract:

    Design of Dryers for biological materials is a complex problem, since in order to solve the model equations, foodstuff physicochemical and equilibrium properties and drying kinetics should be included as a function of water content and operating variables. Shrinkage of biological materials under dehydration must also be taken into account when the macroscopic balances in the bed of drying need to be solved. The main objective of this work was thus to develop a realistic simulation model to predict Batch deep bed drying of shrinkable biological materials. Differential macroscopic balances for heat and mass transfer in the air and solid phases were expressed in moving coordinates in order to solve the problem of particle shrinkage during drying. The equation system was solved by the ‘method of lines’ using the Gear package for temporal derivatives and finite differences for spatial ones. All the parameters and physical properties required to solve the model were taken from literature or determined independently in lab-scale experiments. A pilot-scale hot air Batch dryer was built in order to carry out experimental determinations during drying of slices or cylinders of potato, apple, and carrot at diverse hot air conditions. The appropriate choice of numerical method and initial conditions gave a reliable and stable solution of the equation system. The simulation results agreed closely to experimental data on deep bed Batch drying of food particles under different conditions. The use of variable porosity and volume due to shrinkage during drying improved notably the predictions of the simulation model.Fil: Ratti, Cristina. Laval University; CanadáFil: Crapiste, Guillermo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentin