Parboiled Paddy Drying with Different Dryers: Thermodynamic and Quality Properties, Mathematical Modeling Using ANNs Assessment

The effect of hybrid infrared-convective (IRC), microwave (MIC) and infrared-convective-microwave (IRCM) drying methods on thermodynamic (drying kinetics, effective moisture diffusivity coefficient (Deff), specific energy consumption (SEC)) and quality (head rice yield (HRY), color value and lightness) characteristics of parboiled rice samples were investigated in this study. Experimental data were fitted into empirical drying models to explain moisture ratio (MR) variations during drying. The Artificial Neural Network (ANN) method was applied to predict MR. The IRCM method provided shorter drying time (reduce percentage = 71%) than IRC (41%) and microwave (69%) methods. The Deff of MIC drying (6.85 × 10−11–4.32 × 10−10 m2/s) was found to be more than the observed in IRC (1.32 × 10−10–1.87 × 10−10 m2/s) and IRCM methods (1.58 × 10−11–2.31 × 10−11 m2/s). SEC decreased during drying. Microwave drying had the lowest SEC (0.457 MJ/kg) compared to other drying methods (with mean 28 MJ/kg). Aghbashlo’s model was found to be the best for MR prediction. According to the ANN results, the highest determination coefficient (R2) values for MR prediction in IRC, IRCM and MIC drying methods were 0.9993, 0.9995 and 0.9990, respectively. The HRY (from 60.2 to 74.07%) and the color value (from 18.08 to 19.63) increased with the drying process severity, thereby decreasing the lightness (from 57.74 to 62.17). The results of this research can be recommended for the selection of the best dryer for parboiled paddy. Best drying conditions in the study is related to the lowest dryer SEC and sample color value and the highest HRY and sample lightness.

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Comparative Study of Hot Air Drying and Microwave Drying for Dewatered Sludge

10.21203/rs.3.rs-178542/v1 ◽

2021 ◽

Author(s):

Wittawat Wulyapash ◽

Awassada Phongphiphat ◽

Sirintornthep Towprayoon

Keyword(s):

Microwave Power ◽

Specific Energy Consumption ◽

Microwave Drying ◽

Drying Methods ◽

Drying Time ◽

Hot Air ◽

Air Temperatures ◽

Dewatered Sludge ◽

Dried Sludge ◽

Seafood Processing

Abstract Large amounts of sludge are generated from wastewater treatment in seafood processing industries. Most of the dewatered sludge in Thailand is not utilized and disposed by landfilling. The dried sludge utilization as refuse-derived fuel (RDF) is an alternative solution due to the gross calorific value (GCV), which is greater than 21.9 MJ/kg. However, the key obstacle is its high moisture content of 87.4% (wet basis). Therefore, drying methods using hot air and microwave techniques were investigated for preparing dried sludge. The effects of hot air temperatures (100-150 °C) and microwave power levels (100-800 W) were compared on drying kinetics, specific energy consumption (SEC), and characteristics of the dried products. The results showed that drying times were decreased by increasing the hot air temperatures. In the same way, the increase in microwave power levels decreased the drying time. The application of microwaves contributed to reducing the drying time by more than 46% compared to the hot air. The reduction of drying times resulted in the saving SEC. The GCV of the dried sludge decreased with the decrease in the volatile matter (VM) due to the high component of VM as 79.5-80.3% (dry ash-free basis). The sludge dried by the microwaves showed a lower GCV than the hot air products. However, dried sludges still had high GCV (≥ 20.8 MJ/kg). Furthermore, the minimal variation of the product characteristics demonstrated that the microwave technique could be applied as an alternative drying method with a rapid process compared to the conventional hot air technique.

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Ultrasonic-Microwave and Infrared Assisted Convective Drying of Carrot: Drying Kinetic, Quality and Energy Consumption

Applied Sciences ◽

10.3390/app10186309 ◽

2020 ◽

Vol 10 (18) ◽

pp. 6309

Author(s):

Yousef Abbaspour-Gilandeh ◽

Mohammad Kaveh ◽

Muhammad Aziz

Keyword(s):

Energy Consumption ◽

Hybrid Methods ◽

Specific Energy Consumption ◽

Moisture Diffusivity ◽

Color Variation ◽

Microwave Drying ◽

Convective Drying ◽

Drying Time ◽

Drying Kinetic ◽

The Us

In this study, the drying time, effective moisture diffusivity (Deff), specific energy consumption (SEC), and quality (color, shrinkage, and rehydration) of the ultrasound-pretreated (US) carrot slices were compared when dried by hot air drying (HD), microwave drying (MWD), infrared drying (INFD), and hybrid methods of MW–HD and INF–HD. Five mathematical models were considered to describe the drying kinetics in the carrots. The results show that US+MW–HD and INFD were the fastest and the slowest drying techniques compared to the HD technique with a 73% and 23% drying time reduction, respectively. The Deff ranged from 7.12 × 10−9 to 2.78 × 10−8 m2/s. The highest and lowest SECs were 297.29 ± 11.21 and 23.75 ± 2.22 MJ/kg which were observed in the HD and US+MWD, respectively. The color variation indices indicated that the best sample in terms of color stability was the one dried by US+MW–HD with the color variation of 11.02 ± 0.27. The lowest and highest shrinkage values were also observed in the samples dried by US+MWD and HD (31.8 ± 1.1% and 62.23 ± 1.77%), respectively. Samples dried by US+MWD and HD possessed the highest and lowest rehydration, respectively. Although the carrot slices dried at a higher pace by US+MW–HD (compared to US+MWD), the shrinkage and SEC of the samples dried by US+MWD were significantly lower than the US+MW–HD (p < 0.05). Therefore, it can be concluded that the application of the US+MWD method can be considered as a proper alternative for drying the carrot slices when compared to the HD, MWD, INFD, and hybrid methods.

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Process optimization of paddy drying in cross-flow aerated drying cum storage bin

Agricultural Engineering Today ◽

10.52151/aet2020443.1521 ◽

2020 ◽

Vol 44 (03) ◽

pp. 7-15

Author(s):

Sruthi N. U. ◽

U. C. Lohani ◽

N. C. Shahi ◽

J. P. Pandey

Keyword(s):

Air Temperature ◽

Specific Energy Consumption ◽

Cross Flow ◽

Moisture Diffusivity ◽

Airflow Rate ◽

Experimental Conditions ◽

Heating Chamber ◽

Drying Time ◽

Drying Rates ◽

Drying Conditions

A cross-flow aerated drying cum storage bin was developed and the drying conditions for paddy was optimised. The drying cum storage bin consisted of a cylindrical outer drum with two inner basins having perorated walls made of galvanised iron to hold paddy, and a central perforated vertical duct. A blower (1.5 kW) connected at the base supplies air to the heating chamber (with 1 kW heater coil) and moves vertically through the central duct. The hot air passes horizontally through the grain bulk taking the moisture and moves towards the perforated walls of the bin and exit through the space between the drum and the basins. Drying experiments were conducted with bed thickness of 15 cm to study the drying characteristics of paddy and evaluate the performance of the dryer. Paddy was dried from 18 to 12% (wb) moisture content with the independent parameters selected being drying air temperature (35, 40 and 45 °C) and airflow rate (15, 21 and 27 m3 /h). The drying time varied 1.5 to 4.75 hours over the entire experimental conditions. The analysis of drying rates for both top and bottom bins showed minimum variation indicating uniform drying throughout the depth of the bin. The estimated optimum conditions of drying were 45°C temperature and 27 m3 /h airflow rate. The predicted values of responses at optimised conditions were 1.51 hours of drying time, 6.05x10-7 m2 /s of effective moisture diffusivity, 0.078 W/m2 K of heat transfer coefficient, and 8.23x105 kJ/kg of specific energy consumption. Further, exergy analysis indicated that exergy loss increased with increase in drying air temperature and airflow rate.

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Evaluation of the Changes in Thermal, Qualitative, and Antioxidant Properties of Terebinth (Pistacia atlantica) Fruit under Different Drying Methods

Agronomy ◽

10.3390/agronomy10091378 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1378

Author(s):

Yousef Abbaspour-Gilandeh ◽

Mohammad Kaveh ◽

Hamideh Fatemi ◽

José Luis Hernández-Hernández ◽

Alejandro Fuentes-Penna ◽

...

Keyword(s):

Specific Energy Consumption ◽

Antioxidant Properties ◽

Microwave Drying ◽

Total Phenol Content ◽

Drying Methods ◽

Drying Method ◽

Flavonoid Content ◽

Rehydration Ratio ◽

Drying Time ◽

Hot Air

This study aims to investigate the effect of different drying methods on the thermal, qualitative, and antioxidant properties and pH of terebinth. To perform the experiments in this study, the hot air (HA), infrared (IR), microwave (MW), hot air–infrared (IR–HA), and hot air–microwave drying (MW–HA) methods were considered. The results showed that the minimum drying time was obtained by the hot air–microwave (MW–HA) method. However, the lowest specific energy consumption (SEC) and the highest energy efficiency (ηe) were obtained by the MW method. Considering the color criteria, the best method was obtained by the MW–HA method. The highest amount of rehydration ratio (RR) and the lowest shrinkage (Sb) of the dried terebinth samples were obtained using the MW dryer compared with other drying methods. The MW and MW–HA methods resulted in higher contents of total phenol content (TPC), total flavonoid content (TFC), and antioxidant capacity (AntiOX) than other methods. According to the results of this study, the most effective drying method for terebinth was determined to be the MW and MW-HA methods.

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Thermodynamic and Quality Performance Studies for Drying Kiwi in Hybrid Hot Air-Infrared Drying with Ultrasound Pretreatment

Applied Sciences ◽

10.3390/app11031297 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1297

Author(s):

Ebrahim Taghinezhad ◽

Mohammad Kaveh ◽

Antoni Szumny

Keyword(s):

Energy Efficiency ◽

Mathematical Models ◽

Thermal Efficiency ◽

Specific Energy Consumption ◽

Moisture Diffusivity ◽

Diffusivity Coefficient ◽

Drying Time ◽

Ultrasonic Pretreatment ◽

Hot Air ◽

Drying Efficiency

The present study examined the effect of ultrasonic pretreatment at three time the levels of 10, 20 and 30 min on some thermodynamic (effective moisture diffusivity coefficient(Deff), drying time, specific energy consumption (SEC), energy efficiency, drying efficiency, and thermal efficiency) and physical (color and shrinkage) properties of kiwifruit under hybrid hot air-infrared(HAI) dryer at different temperatures (50, 60 and 70 °C) and different thicknesses (4, 6 and 8 mm). A total of 11 mathematical models were applied to represent the moisture ratio (MR) during the drying of kiwifruit. The fitting of MR mathematical models to experimental data demonstrated that the logistic model can satisfactorily describe the MR curve of dried kiwifruit with a correlation coefficient (R2) of 0.9997, root mean square error (RMSE) of 0.0177 and chi-square (χ2) of 0.0007. The observed Deff of dried samples ranged from 3.09 × 10−10 to 2.26 × 10−9 m2/s. The lowest SEC, color changes and shrinkage were obtained as 36.57 kWh/kg, 13.29 and 25.25%, respectively. The highest drying efficiency, energy efficiency, and thermal efficiency were determined as 11.09%, 7.69% and 10.58%, respectively. The results revealed that increasing the temperature and ultrasonic pretreatment time and decreasing the sample thickness led to a significant increase (p < 0.05) in drying efficiency, thermal efficiency, and energy efficiency, while drying time, SEC and shrinkage significantly decreased (p < 0.05).

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Vacuum-assisted microwave drying characteristics of green bell pepper

International Journal of Food Studies ◽

10.7455/ijfs.v6i1.379 ◽

2017 ◽

Vol 6 (1) ◽

Author(s):

Vivek Kumar ◽

Shanker L. Shrivastava

Keyword(s):

Moisture Diffusivity ◽

Bell Pepper ◽

Microwave Drying ◽

Drying Methods ◽

Drying Time ◽

Drying Characteristics ◽

Hot Air ◽

Potassium Metabisulphite ◽

Temperature Ranges ◽

Air Dryer

Chopped green bell pepper pieces were blanched (95 °C, 5 min) and chemically pretreated (1% potassium metabisulphite solution, 25 min at room temperature) before drying in hot air dryer (HAD) at various temperature ranges (60 – 80 °C). Three vacuum levels (200, 400, 600 mm Hg) and microwave power levels (100, 200, 300 W) were also used to dry green bell pepper samples in a vacuum assisted microwave (VAM) (2.45 GHz, 0.8 kW) dryer. VAM drying methods offered a maximum reduction by four to five times in drying time as compared to that in HAD. The logarithmic model was found to have the best fit based on high R2 and small values of reduced χ2 and RMSE. VAM method has higher values for effective moisture diffusivity (Deff) and lower values for activation energy (Ea), in comparison to the HAD method.

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The drying kinetics and characteristics of Shrimp dried by conventional methods

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq201114050e ◽

2020 ◽

pp. 50-50

Author(s):

Ali Ersan ◽

Nurcan Tugrul

Keyword(s):

Moisture Diffusion ◽

Drying Kinetics ◽

Coefficient Of Determination ◽

Drying Methods ◽

Rehydration Ratio ◽

Vacuum Oven ◽

Drying Time ◽

Quality Properties ◽

Conventional Methods ◽

Drying Conditions

The main purpose of this study was to research the influence of different drying methods on the physical and quality properties of dried shrimps. Shrimps were dried with conventional methods at 60, 70 and 80?C between 330 to 210 minutes and 190 to 110 minutes, in an oven and vacuum oven respectively. Drying time is shortened with the use of vacuum pump. The drying kinetics of the shrimp were studied, and effective moisture diffusion and activation energy were calculated for both methods. The Alibas model and the Midilli & Kucuk model provided the best experimental data with a high coefficient of determination (R2) for oven and the vacuum-oven techniques, respectively. The final dried products were characterized by investigating the colour characteristics, heavy metal content and by carrying out protein analyses. Rehydration ratio was also determined for the dehydrated shrimps. Drying conditions affected the colour features so that shrimps dried in ovens and vacuum ovens showed an increase in brightness and yellowness values and decrease in redness values. The concentration of As, Pb, Cd, Hg, Cu, Zn and Fe in the dried shrimp were within acceptable limits. The protein content of dried shrimp (~85%) is higher than undried shrimp (~20%).

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Estimation of moisture ratio for apple drying by convective and microwave methods using artificial neural network modeling

Scientific Reports ◽

10.1038/s41598-021-88270-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Vali Rasooli Sharabiani ◽

Mohammad Kaveh ◽

Roozbeh Abdi ◽

Mariusz Szymanek ◽

Wojciech Tanaś

Keyword(s):

Specific Energy Consumption ◽

Effective Diffusivity ◽

Moisture Ratio ◽

Microwave Drying ◽

Convective Drying ◽

Neural Network Modeling ◽

Drying Methods ◽

Apple Slices ◽

Artificial Neural ◽

Drying Technology

AbstractTwo different drying methods were applied for dehydration of apple, i.e., convective drying (CD) and microwave drying (MD). The process of convective drying through divergent temperatures; 50, 60 and 70 °C at 1.0 m/s air velocity and three different levels of microwave power (90, 180, and 360 W) were studied. In the analysis of the performance of our approach on moisture ratio (MR) of apple slices, artificial neural networks (ANNs) was used to provide with a background for further discussion and evaluation. In order to evaluate the models mentioned in the literature, the Midilli et al. model was proper for dehydrating of apple slices in both MD and CD. The MD drying technology enhanced the drying rate when compared with CD drying significantly. Effective diffusivity (Deff) of moisture in CD drying (1.95 × 10−7–4.09 × 10−7 m2/s) was found to be lower than that observed in MD (2.94 × 10−7–8.21 × 10−7 m2/s). The activation energy (Ea) values of CD drying and MD drying were 122.28–125 kJ/mol and 14.01–15.03 W/g respectively. The MD had the lowest specific energy consumption (SEC) as compared to CD drying methods. According to ANN results, the best R2 values for prediction of MR in CD and MD were 0.9993 and 0.9991, respectively.

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Optimization and Prediction of the Drying and Quality of Turnip Slices by Convective-Infrared Dryer under Various Pretreatments by RSM and ANFIS Methods

Foods ◽

10.3390/foods10020284 ◽

2021 ◽

Vol 10 (2) ◽

pp. 284

Author(s):

Ebrahim Taghinezhad ◽

Mohammad Kaveh ◽

Antoni Szumny

Keyword(s):

Energy Efficiency ◽

Color Difference ◽

Moisture Diffusivity ◽

Effective Moisture Diffusivity ◽

Diffusivity Coefficient ◽

Drying Process ◽

Anfis Model ◽

Drying Time ◽

Effective Moisture ◽

Response Variables

Drying can prolong the shelf life of a product by reducing microbial activities while facilitating its transportation and storage by decreasing the product weight and volume. The quality factors of the drying process are among the important issues in the drying of food and agricultural products. In this study, the effects of several independent variables such as the temperature of the drying air (50, 60, and 70 °C) and the thickness of the samples (2, 4, and 6 mm) were studied on the response variables including the quality indices (color difference and shrinkage) and drying factors (drying time, effective moisture diffusivity coefficient, specific energy consumption (SEC), energy efficiency and dryer efficiency) of the turnip slices dried by a hybrid convective-infrared (HCIR) dryer. Before drying, the samples were treated by three pretreatments: microwave (360 W for 2.5 min), ultrasonic (at 30 °C for 10 min) and blanching (at 90 °C for 2 min). The statistical analyses of the data and optimization of the drying process were achieved by the response surface method (RSM) and the response variables were predicted by the adaptive neuro-fuzzy inference system (ANFIS) model. The results indicated that an increase in the dryer temperature and a decline in the thickness of the sample can enhance the evaporation rate of the samples which will decrease the drying time (40–20 min), SEC (from 168.98 to 21.57 MJ/kg), color difference (from 50.59 to 15.38) and shrinkage (from 67.84% to 24.28%) while increasing the effective moisture diffusivity coefficient (from 1.007 × 10−9 to 8.11 × 10−9 m2/s), energy efficiency (from 0.89% to 15.23%) and dryer efficiency (from 2.11% to 21.2%). Compared to ultrasonic and blanching, microwave pretreatment increased the energy and drying efficiency; while the variations in the color and shrinkage were the lowest in the ultrasonic pretreatment. The optimal condition involved the temperature of 70 °C and sample thickness of 2 mm with the desirability above 0.89. The ANFIS model also managed to predict the response variables with R2 > 0.96.

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Investigation of influence of pre-treatment and low-temperature on drying kinetics, sorption properties, shrinkage and color of brown seaweeds (Saccharina Latissima)

Proceedings of 21th International Drying Symposium ◽

10.4995/ids2018.2018.7694 ◽

2018 ◽

Author(s):

Ignat Tolstorebrov ◽

Trygve Magne Eikevik ◽

Inna Petrova ◽

Yulia Shokina ◽

Michael Bantle

Keyword(s):

Relative Humidity ◽

Salt Content ◽

Sorption Isotherms ◽

Moisture Diffusivity ◽

Drying Kinetics ◽

Saccharina Latissima ◽

Diffusivity Coefficient ◽

High Accumulation ◽

Drying Time ◽

Brown Seaweeds

Drying kinetics of Saccharina latissima (raw and blanched) at low temperatures (10.0, 25.0 and 38.0 °C) was studied. The effective moisture diffusivity coefficient varied due to temperature alterations in the range between 1.4 and 4.5 10-10 m2/s for raw and 0.91 and 2.56 10-10 m2/s for blanched seaweeds. Significant changes in structural properties and chemical composition resulted in a much longer drying time of blanched seaweeds, when compared with raw. Drying temperature of 38.0 °C resulted in more brown color, when compared with other samples. Sorption characteristics of dried raw seaweeds depended on salt content and showed high accumulation of moisture at relative humidity of air of 80.0 %. The blanched seaweeds showed linear accumulation of moisture within increasing of relative humidity of drying air from 20.0 to 80.0 %, but high level of hysteresis was determined between sorption and desorption isotherms. The shrinkage development within dewatering of blanched and raw samples was also studied. Keywords: brown seaweeds, drying kinetics, sorption isotherms, color

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