scholarly journals Mathematical Modelling of Infra-Red Evaporation Characteristics of Wheat Straw Black Liquor

2021 ◽  
Vol 29 (4) ◽  
Author(s):  
Surendra Pratap Singh ◽  
Mohammad Jawaid ◽  
Bhoomika Yadav ◽  
Mohd Supian Abu Bakar
Keyword(s):  
Activation Energy ◽  
Diffusion Coefficient ◽  
Effective Diffusion Coefficient ◽  
Model Equation ◽  
Evaporation Rate ◽  
Numerical Models ◽  
Linear Regression Analysis ◽  
Black Liquor ◽  
Effective Diffusion ◽  
Chi Square

Infrared (IR) evaporation characteristics of Weak Soda Black Liquor (WSBL) were determined at five different temperatures of 80, 90, 100, 110 and 120oC. The effect of constant temperature on evaporation rate and moisture content (on a dry basis) of 1.5 gm approx. WSBL tests were contemplated and required a careful time frame of IR dissipation to vanish the dampness content at a different consistent temperature. The dissipation rate expanded with expanding infrared temperature. Therefore, different numerical models, such as Page and Logarithmic, Henderson, Pabis and Lewis, were utilised to fit the experimental data properly. A Gaussian model equation was developed for evaporation rate and moisture fraction of black liquor. The probable empirical parameters, along with the relating of reduced chi-square (X2), Residual Sum of Square (RSS), and coefficients of determination (adjusted R2) from non-linear regression analysis of all the numerical model equations, were examined. In addition, the effect of evaporation temperature on the water removal rate, the effective diffusion coefficient and activation energy were also estimated. The effective diffusion coefficient ranges from 2.67 × 10–10 m2/s to 10.4 × 10–10 m2/s, and the activation energy was 39.19 kJ/mol. The statistical indicators (chi-square and determination coefficient) showed that the Decay model equation and Gaussian equation are the most suitable models for describing the evaporation process of WSBL.

scholarly journals Thermodynamic and nutritional properties and drying kinetics of pequi (Caryocar brasiliense Cambess) mesocarp

2019 ◽  
Vol 23 (9) ◽  
pp. 655-661 ◽  
Author(s):  
Jéssica L. F. Souza ◽  
Daniel E. C. Oliveira ◽  
Geovana R. Plácido ◽  
Mariana B. Egea ◽  
Márcio Caliari ◽  
...  
Keyword(s):  
Activation Energy ◽  
Diffusion Coefficient ◽  
Moisture Content ◽  
Mathematical Models ◽  
Effective Diffusion Coefficient ◽  
Linear Regression Analysis ◽  
Effective Diffusion ◽  
Initial Moisture Content ◽  
Nutritional Properties ◽  
Drying Temperature

ABSTRACT The objectives of this study were to fit mathematical models to the experimental data of the drying of the pequi mesocarp, determine the effective diffusion coefficient, and to obtain activation energy and thermodynamic and nutritional properties in different drying conditions. The mesocarp of pequi fruits, with an initial moisture content of 5.05 (decimal, dry basis), was dried in a forced ventilation oven at temperatures of 40, 50, 60 and 70 °C until the final moisture content of 0.15 ± 0.01 (decimal, dry basis). The mathematical models were adjusted by non-linear regression analysis using the Gauss-Newton method, considering the magnitude of the coefficient of determination (R2), the mean relative error (P) and the estimated mean error (SE). Among the models analyzed, the Midilli model presented the best fit. The effective diffusion coefficient increased with increase in temperature, and the activation energy on drying was 11.011 kJ mol-1. The enthalpy decreased with an increase in the drying temperature, while the entropy and Gibbs free energy increased with the drying temperature. The product obtained from drying has low lipid and high carbohydrate concentration, while temperatures above 70 °C could cause denaturation and/or protein complexation. The temperature of 60 °C is most suitable to obtain flour of pequi mesocarp, due to the shorter processing time while maintaining the nutritional quality.

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.

scholarly journals Thermodynamic properties and drying kinetics of ‘okara’

2018 ◽  
Vol 22 (6) ◽  
pp. 418-423 ◽  
Author(s):  
Rafaiane M. Guimarães ◽  
Daniel E. C. de Oliveira ◽  
Osvaldo Resende ◽  
Jhessika de S. Silva ◽  
Thaisa A. M. de Rezende ◽  
...  
Keyword(s):  
Activation Energy ◽  
Diffusion Coefficient ◽  
Thermodynamic Properties ◽  
Effective Diffusion Coefficient ◽  
Effective Diffusion ◽  
Drying Kinetics ◽  
Water Soluble ◽  
Soluble Extract ◽  
Constant Weight ◽  
Water Soluble Extract

ABSTRACT ‘Okara’ is the insoluble part obtained after the aqueous extraction of soybeans, generated in large quantities as a by-product of the ‘tofu’ industry or soybean water-soluble extract. This work aimed to study ‘okara’ convective drying kinetics, determine the effective diffusion coefficient, and obtain activation energy and thermodynamic properties under different drying conditions. The by-product ‘okara’ was obtained from the processing of BRS 257 soybean water-soluble extract, homogenized and dried in a forced-air oven at temperatures of 40, 50, 60 and 70 °C until constant weight. Among the analysed models, Wang & Singh was selected to represent the drying phenomenon. Effective diffusion coefficient increased with the temperature rise, and the activation energy for the net diffusion in the drying was 28.15 kJ mol-1. Enthalpy and Gibbs free energy increased with the elevation of drying temperature.

scholarly journals Drying kinetics of yellow mombin (Spondias mombin L.) epicarp

2020 ◽  
Vol 24 (2) ◽  
pp. 121-127
Author(s):  
Gleyce K. I. Pinheiro ◽  
Daniel E. C. de Oliveira ◽  
Weder N. Ferreira Junior ◽  
Osvaldo Resende
Keyword(s):  
Experimental Data ◽  
Activation Energy ◽  
Diffusion Coefficient ◽  
Effective Diffusion Coefficient ◽  
Effective Diffusion ◽  
Initial Moisture Content ◽  
Sweet Taste ◽  
Information Criteria ◽  
Spondias Mombin ◽  
Drying Conditions

ABSTRACT Yellow mombin (Spondias mombin L.) fruits have relevant characteristics for industrialization and exhibit a pleasant aroma and sour-sweet taste, with significant amounts of vitamin A and carotenoids in their epicarp. The objective was to fit different mathematical models to the experimental data, using as criteria to select the best model - the Akaike Information Criteria (AIC) and Schwarz’s Bayesian Information Criteria (BIC), as well as to evaluate the effective diffusion coefficient and to determine the activation energy for yellow mombin epicarp submitted to different drying conditions. The experiment was carried out at the Instituto Federal de Educação, Ciência e Tecnologia Goiano, Brazil The epicarp of yellow mombin fruits with initial moisture content of 2.89 (dry basis, d.b.) were submitted to drying at temperatures of 40, 50, 60 and 70 °C until final moisture contents of 0.11, 0.10, 0.09 and 0.08 (d.b.), respectively. The Midilli model showed the best fit to the experimental data obtained. The choice of the model was confirmed by the AIC and BIC criteria. The increase of the drying temperature promoted increase in the effective diffusion coefficient, and the activation energy of the process was 21.50 kJ mol-1.

scholarly journals Modeling and thermodynamic properties of the drying of tamarind (Tamarindus indica L.) seeds

2021 ◽  
Vol 25 (1) ◽  
pp. 37-43
Author(s):  
Weder N. Ferreira Junior ◽  
Osvaldo Resende ◽  
Gleyce K. I. Pinheiro ◽  
Lígia C. de M. Silva ◽  
Diene G. Souza ◽  
...  
Keyword(s):  
Experimental Data ◽  
Activation Energy ◽  
Diffusion Coefficient ◽  
Thermodynamic Properties ◽  
Effective Diffusion Coefficient ◽  
Effective Diffusion ◽  
Initial Moisture Content ◽  
Tamarindus Indica ◽  
Nonlinear Regression Models ◽  
Federal Institute

ABSTRACT In the present study, the objective was to fit different models to the experimental data of drying of tamarind (Tamarindus indica L.) seeds and to select the best model, to determine the effective diffusion coefficient, activation energy and thermodynamic properties for the process during drying at different temperatures. The experiment was carried out at the Laboratory of Post-Harvest of Vegetable Products of the Instituto Federal Goiano (Federal Institute Goiano) - Campus of Rio Verde, GO, Brazil. Seeds with initial moisture content of 18 ± 0.25% dry basis were oven dried with forced air ventilation, at controlled temperatures of 45, 60, 75 and 90 °C in four repetitions. Nonlinear regression models used to describe the phenomenon were fitted to the experimental data. To represent the drying of tamarind seeds, the Midilli model was selected for the range from 45 to 60 ºC and the Two terms model was selected for the range from 75 to 90 ºC. The effective diffusion coefficient increases with the increase of drying air temperature, being described by the Arrhenius equation, with activation energy of 35.16 kJ mol-1. Enthalpy and entropy decreases, while Gibbs free energy increases with increasing drying temperature.

scholarly journals Mathematical modeling and effect of thin-layer drying and lyophilization on antioxidant compounds from ultrasonic-assisted extracted Muntingia calabura peels

2021 ◽  
Vol 43 ◽  
pp. e50301
Author(s):  
Luciana Alves da Silva Tavone ◽  
Kauyse Matos Nascimento ◽  
Yasmin Jaqueline Fachina ◽  
Grasiele Scaramal Madrona ◽  
Rita de Cássia Bergamasco ◽  
...  
Keyword(s):  
Activation Energy ◽  
Antioxidant Activity ◽  
Diffusion Coefficient ◽  
Phenolic Compounds ◽  
Bioactive Compounds ◽  
Effective Diffusion Coefficient ◽  
Effective Diffusion ◽  
Drying Temperature ◽  
Thin Layer Drying ◽  
Muntingia Calabura

Muntingia calabura fruits are rich in bioactive compounds such as antioxidants, and the consumption of these compounds is associated with cancer prevention and aging. In this study, mathematical models were used to fit the experimental data of the Muntingia calabura peel drying kinetics, and the effective diffusion coefficient, activation energy and thermodynamic properties of the process were determined. Then, the effect of the drying temperature on the antioxidant activity and phenolic compounds of fruit peels was examined using conventional extraction and ultrasonication. Among the analyzed models, the logarithmic model was selected to represent the drying phenomenon of the calabura peel kinetics. The effective diffusion coefficient decreased by 74% as the temperature increased from 40 to 60°C, and the activation energy for liquid diffusion during drying was 23.96 kJ mol-1. The enthalpy and entropy decreased with increasing temperature, while the Gibbs free energy increased by 5% for each 10°C increase in temperature. Regarding the content of phenolic compounds and the antioxidant activity of the calabura peel, it was observed that an increase in the drying temperature had a positive effect on the conservation of the bioactive compounds, making it possible to conclude that drying at 60°C and ultrasound extraction are the most suitable approach to conduct the process.

scholarly journals Model for Thin Layer Drying of Lemongrass (Cymbopogon citratus) by Hot Air

Processes ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 21 ◽  
Author(s):  
Thi Van Linh Nguyen ◽  
My Duyen Nguyen ◽  
Duy Chinh Nguyen ◽  
Long Giang Bach ◽  
Tri Duc Lam
Keyword(s):  
Activation Energy ◽  
Diffusion Coefficient ◽  
Effective Diffusion Coefficient ◽  
Removal Rate ◽  
Effective Diffusion ◽  
Suitable Model ◽  
Moisture Removal ◽  
Drying Process ◽  
Drying Temperature ◽  
Thin Layer Drying

Lemongrass is a plant that contains aromatic compounds (myrcene and limonene), powerful deodorants, and antimicrobial compounds (citral and geraniol). Identifying a suitable drying model for the material is crucial for establishing an initial step for the development of dried products. Convection drying is a commonly used drying method that could extend the shelf life of the product. In this study, a suitable kinetic model for the drying process was determined by fitting moisture data corresponding to four different temperature levels: 50, 55, 60 and 65 °C. In addition, the effect of drying temperature on the moisture removal rate, the effective diffusion coefficient and activation energy were also estimated. The results showed that time for moisture removal increases proportionally with the air-drying temperature, and that the Weibull model is the most suitable model for describing the drying process. The effective diffusion coefficient ranges from 7.64 × 10−11 m2/s to 1.48 × 10−10 m2/s and the activation energy was 38.34 kJ/mol. The activation energy for lemongrass evaporation is relatively high, suggesting that more energy is needed to separate moisture from the material by drying.

scholarly journals Post-harvesting of Solanum paniculatum L. leaves. Part I: Drying kinetics

2020 ◽  
Vol 24 (8) ◽  
pp. 560-566
Author(s):  
Elton A. S. Martins ◽  
André L. D. Goneli ◽  
Alexandre A. Gonçalves ◽  
Valdiney C. Siqueira ◽  
Claúdia A. L. Cardoso ◽  
...  
Keyword(s):  
Activation Energy ◽  
Diffusion Coefficient ◽  
Medicinal Plants ◽  
Air Temperature ◽  
Effective Diffusion Coefficient ◽  
Effective Diffusion ◽  
Drying Kinetics ◽  
Drying Time ◽  
Air Temperatures ◽  
Air Speed

ABSTRACT Solanum paniculatum L. (jurubeba) is among the numerous medicinal plants used by the Brazilian population, and the use of its leaves is quite popular, in the form of tea, as a remedy against hangovers after excessive consumption of alcohol and food, besides being used in the form of ointments as healing agent and also in the treatment of liver and digestive problems. Leaves of medicinal plants usually have a high moisture content, requiring its reduction by drying, so that the product can be stored safely until its processing. The objective of this study was to evaluate the drying kinetics of jurubeba leaves and to determine the effective diffusion coefficient and activation energy during drying. Jurubeba leaves were dried at different air temperatures (30, 40, 50, 60 and 70 °C) and speed (0.4 and 0.8 m s-1). The Midilli model satisfactorily fitted to the observed data of drying of jurubeba leaves for all air conditions. Increasing the drying air temperature and speed reduced the drying time and increased the effective diffusion coefficient. For the air temperature range from 40 to 70 °C, as the drying air speed increases, the activation energy for the drying of the jurubeba leaves is reduced.

scholarly journals Drying kinetics of blackberry leaves

2018 ◽  
Vol 22 (8) ◽  
pp. 570-576 ◽  
Author(s):  
Elton A. S. Martins ◽  
André L. D. Goneli ◽  
Alexandre A. Goncalves ◽  
Cesar P. Hartmann Filho ◽  
Valdiney C. Siqueira ◽  
...  
Keyword(s):  
Activation Energy ◽  
Diffusion Coefficient ◽  
Effective Diffusion Coefficient ◽  
Effective Diffusion ◽  
Fixed Bed ◽  
Drying Kinetics ◽  
Drying Time ◽  
Thin Layer Drying ◽  
Air Speed ◽  
Kinetics Of

ABSTRACT Blackberry leaves have some pharmacological properties and one of the most widespread and studied uses is to relieve symptoms of the climacteric and other symptoms during the premenstrual period. Thus, drying becomes important for the conservation and storage of the product until its use or processing. The present study aimed to evaluate the drying kinetics of blackberry leaves, as well as to determine the effective diffusion coefficient and the activation energy during the drying process. Blackberry leaves were dried in an experimental fixed-bed dryer under four controlled temperature conditions (40, 50, 60 and 70 °C) and two drying air speeds (0.4 and 0.8 m s-1). With the experimental data of moisture ratio, eight mathematical models were fitted to represent the process of thin-layer drying of agricultural products. Based on the obtained results, it was found that the Midilli model represented best the phenomenon of drying of blackberry leaves. The increase in temperature and air speed reduced the drying time of blackberry leaves and increased the values of the effective diffusion coefficient. This relation can be described by the Arrhenius equation, which has an activation energy for the liquid diffusion during drying of 65.94 and 66.08 kJ mol-1, for drying air speeds of 0.4 and 0.8 m s-1, respectively.

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