scholarly journals Study of the forms of moisture bond in coriander seeds based on analysis of drying kinetics

2020 ◽  
Vol 82 (3) ◽  
pp. 24-31
Author(s):  
S. T. Antipov ◽  
D. A. Kazartsev ◽  
A. M. Davydov ◽  
A. B. Emelyanov
Keyword(s):  
Moisture Content ◽  
The State ◽  
Binding Energies ◽  
Drying Kinetics ◽  
Rate Of Change ◽  
Qualitative Assessment ◽  
Laboratory Research ◽  
Critical Moisture Content ◽  
Critical Moisture ◽  
Kinetics Of

The article deals with the issues related to the study of the forms of connection of moisture removed during the drying of coriander seeds. A study was carried out to determine the quantitative moisture content of various forms of communication by two methods and a comparative analysis was carried out. It is shown that the existing methods for studying the forms of moisture-material bond have significant drawbacks and generally give a qualitative assessment of the state of moisture in the material or are very laborious and require lengthy laboratory research. An approach is proposed to determine the forms of moisture bond in coriander seeds based on graph-analytical analysis of the drying kinetics, which makes it possible to qualitatively and quantitatively assess the state of moisture in the seeds. With the help of a graphical editor, the curves of the kinetics of drying of coriander seeds were processed and the dependences of the value characterizing the rate of change in the rate of drying of coriander seeds on the moisture content of the product were obtained, and the introduction of a new concept into the theory of drying of this value as "acceleration of drying" was proposed. The analysis of the obtained curves is carried out, indicating the presence of extrema and points of inflection to the corresponding critical moisture content, as well as the presence of areas with a slowdown or acceleration of the drying rate change, which make it possible to establish the intervals of moisture removal with different binding energies. The approach considered in the article to determine the forms of moisture bond in coriander seeds will allow not only to give a qualitative and quantitative assessment of the state of moisture in products, but also to reduce the time spent on analysis and increase the accuracy of the results.

scholarly journals Isotermas de adsorção de umidade e cinética de secagem de sementes de trevo persa (Trifolium resupinatum L.) e trevo vesiculoso (Trifolium vesiculosum) ¬¬¬¬

2020 ◽  
Vol 28 ◽  
pp. 535-548
Author(s):  
Gabriela Saldanha Soares ◽  
Scarlet Neves Tuchtenhagen ◽  
Luiz Antonio de Almeida Pinto ◽  
Carlos Alberto Severo Felipe
Keyword(s):  
Moisture Content ◽  
Adsorption Isotherms ◽  
Effective Diffusivity ◽  
Drying Kinetics ◽  
Peleg Model ◽  
Critical Moisture ◽  
Persian Clover ◽  
Trifolium Vesiculosum ◽  
Kinetics Of ◽  
Trifolium Resupinatum

The aim of this work was to obtain adsorption isotherms and to study the drying kinetics of persian clover (Trifolium resupinatum L.) and arrowleaf clover (Trifolium vesiculosum) seeds, in addition, fitting the experimental data by the predicted models of the literature. The equilibrium moisture content and the moisture adsorption behavior were found by isotherms curves at 40, 45 and 50 ºC, and the Peleg model was the most suitable. The drying kinetics was determined by thin layer assays in an air parallel flow dryer at all three temperatures. In addition, it was demonstrated the predominance of the falling drying rate period for the two species of seeds, and the critical moisture content values were approximately of 0.20 and 0.25 gwater gdry matter-1 for persian clover and arrowleaf clover seeds, respectively. The effective diffusivity values were estimated in ranges of values of 3.61×10-11 – 6.81×10-11 m² s-1 for persian clover and 6.76×10-11 – 1.15×10-10 m²s-1 for arrowleaf clover seeds and the temperature effect was expressed by an Arrhenius relation. Thus, drying kinetics confirmed the greater difficulty in moisture removal from the arrowleaf clover seeds, compared to the persian clover seeds drying, in agreement with the results obtained through adsorption isotherms.

scholarly journals ON CALCULATION OF DRYING KINETICS OF THERMOLABILE LIQUID DISPERSED PRODUCTS ON SUBSTRATES

2020 ◽  
Vol 63 (3) ◽  
pp. 100-107
Author(s):  
Andrey N. Pakhomov ◽  
Natalia Ts. Gatapova ◽  
Natalia V. Orlova ◽  
Yulia V. Pakhomova
Keyword(s):  
Fractal Dimension ◽  
Moisture Content ◽  
Solid Phase ◽  
Surface Film ◽  
Product Layer ◽  
Fractal Cluster ◽  
Critical Moisture Content ◽  
Critical Moisture ◽  
Horizontal Substrate ◽  
Kinetics Of

For the drying process of a liquid dispersed product layer on a horizontal substrate, a model for the formation of a solid phase particle residue is proposed. The model is based on the construction of a fractal cluster on a bounded spatial lattice according to given rules. The model is constructed on the basis of ideas about the mechanism of interaction of particles during the existence of a layer of free liquid in the drying product. The fractal model, which has the property of self-similarity of the forming structure, allows modeling spatial structures on bounded lattices and spreading the data obtained on bounded lattices to the entire volume of the simulated residue. The article provides a brief overview of the main works related to the application of the fractal concept in the modeling of micro and macroscopic structures arising during the drying of liquid products. It is shown that in order to calculate the kinetics of drying liquid dispersed products on substrates, in the case of the formation of a certain layer of surface film and the formation of a certain spatial structure of solid particles, an important task is to determine the critical moisture content. The proposed model allows modeling layers with fractal dimension lying in the range from 1.64 to 2. This range corresponds to layers in the porosity range from layers with dense monodisperse particle stacking with a coordination number of 12, to structures similar to dendrite fractals, with porosity much higher than the ordered simple cubic particle stacking. The results of fractal cluster modeling and comparison of calculated and experimental values of porosity and critical moisture content obtained in the process of drying a suspension of optical bleach CD-2 and polymethylene-B-naphthalene sulfonate under different modes of convective drying of the product layer on a fluoroplastic horizontal substrate as products characterized by a close value of the initial concentration of the solid phase (≈12%), but different values of particle sizes and the obtained values of the fractal dimension of the surface film and the dry residue are presented.

Drying kinetics of processed natural coffee with high moisture content

2017 ◽  
Vol 12 (3) ◽  
pp. 400 ◽  
Author(s):  
Valdiney Cambuy Siqueira ◽  
Flávio Meira Borém ◽  
Guilherme Euripedes Alves ◽  
Eder Pedroza Isquierdo ◽  
Afonso Celso Ferreira Pinto ◽  
...  
Keyword(s):  
Moisture Content ◽  
Drying Kinetics ◽  
High Moisture Content ◽  
High Moisture ◽  
Kinetics Of

Objetivou-se, com o presente trabalho, propor um novo método de processamento e secagem, assim como avaliar o comportamento dos grãos submetidos a este processo, por meio da taxa de redução de água e do ajuste de diferentes modelos matemáticos aos dados experimentais da secagem. Os frutos colhidos no estágio maduro foram divididos em três lotes. O primeiro foi seco continuamente à temperatura de 40±1 °C. O segundo consiste na secagem do café natural até os teores de água de 0,56±0,02, 0,41±0,02, 0,28±0,02 e 0,20±0,02 decimal (base seca, b.s.), seguido de beneficiamento e secagem contínua nas temperaturas de 35±1 ºC e 40±1 ºC. O terceiro lote correspondeu à secagem contínua do café descascado e desmucilado na temperatura de 40±1 °C. Em todos os lotes, a secagem foi encerrada quando os grãos atingiram o teor de água de 0,12±0,05 (b.s.). Aos dados experimentais da secagem foram ajustados dez modelos matemáticos utilizados para representação da secagem dos produtos agrícolas. Além da representação da cinética de secagem foi avaliada a taxa de redução de água dos grãos. Conclui-se que a taxa de redução de água é maior para a temperatura de secagem de 40±1 °C, especialmente para maiores teores de água. O tempo total de secagem do café beneficiado com alto teor de água é expressivamente reduzido, quando comparado ao tempo de secagem completa do café natural. O modelo de Midilli descreve satisfatoriamente a cinética de secagem do café beneficiado.

scholarly journals Drying Kinetics of Noni Seeds

2019 ◽  
Vol 11 (5) ◽  
pp. 250 ◽  
Author(s):  
Wellytton Darci Quequeto ◽  
Osvaldo Resende ◽  
Patrícia Cardoso Silva ◽  
Fábio Adriano Santos e Silva ◽  
Lígia Campos de Moura Silva
Keyword(s):  
Experimental Data ◽  
Activation Energy ◽  
Diffusion Coefficient ◽  
Moisture Content ◽  
Mathematical Models ◽  
Effective Diffusion Coefficient ◽  
Effective Diffusion ◽  
Information Criterion ◽  
Drying Kinetics ◽  
Kinetics Of

Noni seeds have been used for years as an important medicinal source, with wide use in the pharmaceutical and food industry. Drying is a fundamental process in the post-harvest stages, where it enables the safe storage of the product. Therefore, the present study aimed to fit different mathematical models to experimental data of drying kinetics of noni seeds, determine the effective diffusion coefficient and obtain the activation energy for the process during drying under different conditions of air temperature. The experiment used noni seeds with initial moisture content of 0.46 (decimal, d.b.) and dehydrated up to equilibrium moisture content. Drying was conducted under different controlled conditions of temperature, 40; 50; 60; 70 and 80 ºC and relative humidity, 24.4; 16.0; 9.9; 5.7 and 3.3%, respectively. Eleven mathematical models were fitted to the experimental data. The parameters to evaluate the fitting of the mathematical models were mean relative error (P), mean estimated error (SE), coefficient of determination (R2), Chi-square test (c2), Akaike Information Criterion (AIC) and Schwarz’s Bayesian Information Criterion (BIC). Considering the fitting criteria, the model Two Terms was selected to describe the drying kinetics of noni seeds. Effective diffusion coefficient ranged from 8.70 to 23.71 × 10-10 m2 s-1 and its relationship with drying temperature can be described by the Arrhenius equation. The activation energy for noni seeds drying was 24.20 kJ mol-1 for the studied temperature range.

Influence of Osmotic Pre-treatment on Convective Drying Kinetics of Figs

2013 ◽  
Vol 9 (2) ◽  
pp. 187-196 ◽  
Author(s):  
Juliana M. Silva ◽  
Muriel G. Cantu ◽  
Vera Rodrigues ◽  
Marcio A. Mazutti
Keyword(s):  
Experimental Data ◽  
Moisture Content ◽  
Osmotic Dehydration ◽  
Sucrose Concentration ◽  
Drying Kinetics ◽  
Soluble Solids ◽  
Convective Drying ◽  
Final Time ◽  
Osmotic Treatment ◽  
Kinetics Of

AbstractThis work evaluated the effects of osmotic dehydration on convective drying kinetics of figs. It used the experimental design methodology to evaluate the influence of sucrose concentration, temperature and time on the amount of total soluble solids (TSS) and moisture content of the figs. After the osmotic dehydration, it evaluated the convective drying kinetics at temperatures from 55 to 75°C. A mathematical model was employed to fit the experimental data. From the experimental data of the osmotic dehydration, it was seen that the moisture content of the figs after the treatment was closely related to the amount of TSS of the figs. Low moisture content and high TSS content were obtained for a narrow range of independent variables comprised between 55–60°C, 55–63 wt% and 260–280 min for temperature, sucrose concentration and exposure time, respectively. In the convective drying kinetics of the figs, there were no verified significant differences in the final time of drying of non-treated and osmotically dehydrated figs. However, the shrinkage was considerably reduced in the osmotically treated figs. The use of osmotic treatment enables the obtainment of figs softer than the simple use of convective drying without changing the final time of drying.

Comparison of Drying Kinetics of Maize in Oven and in Pilot Silo Dryer: Influence on Moisture Content and Physical Characteristics

2016 ◽  
Vol 12 (6) ◽  
pp. 599-606 ◽  
Author(s):  
Flávia Daiana Montanuci ◽  
Raphaela Mulato Cavalcante ◽  
Camila Augusto Perussello ◽  
Luiz Mario de Matos Jorge
Keyword(s):  
Moisture Content ◽  
Temperature Increase ◽  
Drying Kinetics ◽  
Final Moisture Content ◽  
Drying Rate ◽  
Drying Time ◽  
Drying Temperature ◽  
Design And Optimization ◽  
Process Kinetics ◽  
Kinetics Of

Abstract The study of process kinetics may aid the design and optimization of drying systems. This paper evaluated the influence of drying temperature (40, 60 and 80 °C) on the moisture content, drying rate, density, shrinkage and breakage of maize dried in two different dryers: oven and silo dryer. In both dryers, the temperature increase reduced drying time, final moisture content and shrinkage of the grains, however increased breakage. Drying rate was higher in the oven (6.4×10−4±2.3×10−4s−1 versus 5.4×10−4±1.2×10−4s−1), while shrinkage (15.2±4.7 % versus 24.4±5.6 %) and density increase (16.6±5.9 % versus 33.4±5.8 %) were more intense in the silo. There was a large release of husk in the silo dryer and the moisture content was slightly smaller in the lower layers respective to the upper ones.

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