scholarly journals Mathematical Model for Solar Drying of Grains

2019 ◽  
pp. 1-18
Author(s):  
A. O. Fagunwa ◽  
O. A. Aregbesola ◽  
M. O. Faborode
Keyword(s):  
Mathematical Model ◽  
Thermal Properties ◽  
Moisture Content ◽  
Climatic Conditions ◽  
Drying Rate ◽  
Solar Drying ◽  
Drying Process ◽  
Complex Procedure ◽  
Unique Method ◽  
Complex Phenomena

Mathematical modeling of drying process is a complex procedure that should be carefully done. Moreso, model for solar drying, which is a unique method of drying due to constant fluctuation in the climatic conditions, requires complete integration of the complex phenomena that are involved for accurate prediction of moisture content and drying rate. A mathematical model was developed from heat and mass balance equation considering the physical and thermal properties of the grain, meteorological factors and convective heat transfer during solar drying of grains. The data obtained from the model was compared with experimental results obtained using a solar dryer to dry five selected grains – cowpea, soyabean, groundnut, maize and sorghum at airflow rates of 0.22 m/s, 0.76 m/s and 0.94 m/s. The results from statistical analysis and regression analyses used to compare the results showed that the model is adequate in predicting the moisture content and drying rate of the selected grains as well as other agricultural products with closer physical and thermal properties.

CATFISH DRYING (Clarias Batraclus) USING ‘TEKO BERSAYAP’ SOLAR DRYER

2012 ◽  
Vol 2 (1) ◽  
pp. 14-20
Author(s):  
Yuwana Yuwana
Keyword(s):  
Relative Humidity ◽  
Moisture Content ◽  
Ambient Temperature ◽  
Drying Rate ◽  
Drying Process ◽  
Drying Time ◽  
Ambient Relative Humidity ◽  
Solar Dryer

Experiment on catfish drying employing ‘Teko Bersayap’ solar dryer was conducted. The result of the experiment indicated that the dryer was able to increase ambient temperature up to 44% and decrease ambient relative humidity up to 103%. Fish drying process followed equations : KAu = 74,94 e-0,03t for unsplitted fish and KAb = 79,25 e-0,09t for splitted fish, where KAu = moisture content of unsplitted fish (%), KAb = moisture content of splitted fish (%), t = drying time. Drying of unsplitted fish finished in 43.995 hours while drying of split fish completed in 15.29 hours. Splitting the fish increased 2,877 times drying rate.

Simulation and Performance of a Solar Drying Unit with Storage for Aromatic and Medicinal Plants

2015 ◽  
Vol 11 (5) ◽  
pp. 597-607 ◽  
Author(s):  
M. Ayadi ◽  
I. Zouari ◽  
A. Bellagi
Keyword(s):  
Medicinal Plants ◽  
Mathematical Formulation ◽  
Climatic Conditions ◽  
Drying Rate ◽  
Solar Drying ◽  
Aromatic And Medicinal Plants ◽  
Transfer Equations ◽  
And Performance ◽  
Drying Curves ◽  
Main Factor

Abstract The objective of this work, based on a theoretical and experimental study, is to investigate the energy and economic performance of a totally solar drying unit with storage for aromatic and medicinal plants, to satisfy a dimensioning already carried out on a macroscopic scale for an energy request well defined: to dry a quantity of a given agricultural products during 1 day of harvest season, so between September and May, with a heat storage which relays at night. Drying experiments were conducted for spearmint grown in Tunisia. Mathematical formulation of the physical process of this solar drying unit based on conventional heat and mass transfer equations showed a certain agreement with the experimental results under climatic conditions of Tunis (Tunisia). All the experimental drying curves showed only a falling drying rate period. The main factor in controlling the drying rate was found to be the drying air temperature. It was observed that this unit is able to dry more than 2.5 kg of spearmint per day with a moisture reduction efficiency of 70%. It was found that for all the period of harvest, so for 5 months assumed dryer used per year, the payback period is 3.6 years.

Analytic Study on On-Line Model of Moisture in Hot Air Drying Process of Grain

2017 ◽  
Vol 872 ◽  
pp. 360-372
Author(s):  
Zhi Wei Mai ◽  
Bi Ying Wang ◽  
Chang You Li
Keyword(s):  
Moisture Content ◽  
Cross Flow ◽  
Drying Rate ◽  
Drying Process ◽  
Counter Flow ◽  
Drying Characteristics ◽  
Concurrent Flow ◽  
Content Ratio ◽  
Real Time Tracking ◽  
Drying Technology

This study aims to review variation pattern of moisture content ratio of grains in deep-bed drying process, guide the drying technology design, realize real-time tracking and regulation in drying process, improve the quality of drying process and reduce energy consumption. Based on the moisture diffusion model in thin layer drying process, the principle of mass conservation of deep drying process, state function and irreversible thermodynamics analytic method, we have established and solved basic equations of deep-bed drying of grains, obtained the moisture content ratio of grains and analysis formula of drying velocity distribution in processes of concurrent flow drying, counter flow drying, cross-flow drying and standing drying and resolved the sustained decreasing drying process of grains in the concurrent flow drying and extreme point of drying rate in the counter-flow drying. Under the same conditions of temperature, humidity and air output, the drying velocity in counter-flow drying significantly higher than that in the concurrent flow drying. It means the energy utilization effects in counter-flow drying is better than that in the concurrent flow drying. Drying characteristics of grains in cross-flow drying and standing flow drying are the same, while drying rates in inlet-air side and outlet-air side vary widely. It means that when the layer thickness is 0.5m and the moisture content is over 20%, the drying rate in outlet-air side is nearly zero and the drying uniformity is bad. Tests on 5HP-3.5 recirculation drier shows that maximum deviation between analytic value and measured value in deep drying process is 0.69% and the range scope is -0.27%-0.69%. From the drying characteristics of grains, deviations mainly come from instrument detection deviations. The analytic method has important significance for realizing real-time tracking and regulation in drying process, guiding drying technology design, reducing energy consumption, increasing drying rate and drying machine capacity.

scholarly journals Effect of steam thermal treatment on the drying process of Eucalyptus dunnii variables

CERNE ◽  
2013 ◽  
Vol 19 (4) ◽  
pp. 637-645 ◽  
Author(s):  
Elias Taylor Durgante Severo ◽  
Ivan Tomaselli ◽  
Fred Willians Calonego ◽  
André Luiz Ferreira ◽  
Lourival Marin Mendes
Keyword(s):  
Moisture Content ◽  
Initial Moisture Content ◽  
Moisture Gradient ◽  
Steam Treatment ◽  
Drying Rate ◽  
Drying Process ◽  
Intermediate Layers ◽  
Eucalyptus Dunnii ◽  
Electric Oven ◽  
Heating Up

The aim of this study was to evaluate the effect of steam treatment prior to drying on the initial moisture content, moisture gradient, and drying rate in Eucalyptus dunnii Maiden wood. Boards were steamed at 100ºC for 3 h after 1 h of heating-up. Part of these boards was dried in a drying electric oven at 50ºC, and part was dried at kiln. The results showed that the steaming prior to drying of wood: (1) significantly reduced by 9.2% the initial moisture content; (2) significantly increased by 6.2% the drying rate; (3) significantly decreased by 15.6 and 14.8% the moisture gradient between the outer layer and the center of boards and between the outer and intermediate layers of boards, respectively. Steamed boards when dried in an oven showed drying rate of 0.007065 whereas in kiln were 0.008200 and 0.034300 from green to 17 and 17 to 12% moisture content, respectively. It was demonstrated that the steaming prior to drying can be suitable for reduces the drying times of this kind of wood.

Non-Deterministic Description of Wood Radio Frequency Vacuum Drying

Holzforschung ◽  
2003 ◽  
Vol 57 (1) ◽  
pp. 88-94 ◽  
Author(s):  
D. Elustondo ◽  
A. Koumoutsakos ◽  
S. Avramidis
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Standard Deviation ◽  
Moisture Content ◽  
Radio Frequency ◽  
Western Hemlock ◽  
Vacuum Drying ◽  
Drying Process ◽  
Stochastic Parameters ◽  
Deterministic Description

Summary A numerical method is proposed to predict the stochastic dispersion of data that unavoidably occurs in a real drying process. The method is based on the use of discrete frequency distribution curves to predict a random variation on some parameters of the process and is applied to the case of radio frequency vacuum (RFV) drying of wood. Experimental data of RFV drying of western hemlock timbers were used to obtain the numeric values of the stochastic parameters and their standard deviation. A mathematical model was designed to simulate the final moisture content dispersion on hypothetical examples. Results were quantified using three indices: average, range and standard deviation.

Impregnation and Drying Schedule of Eucalyptus Wood

2011 ◽  
Vol 71-78 ◽  
pp. 860-863
Author(s):  
Guo Feng Wu ◽  
Qian Lang ◽  
Shu Ping Song ◽  
Jun Wen Pu
Keyword(s):  
Standard Deviation ◽  
Moisture Content ◽  
Wood Fiber ◽  
Basic Density ◽  
Untreated Wood ◽  
Drying Rate ◽  
Hot Press ◽  
Drying Process ◽  
Eucalyptus Wood ◽  
Wood Composition

The aim of this research was to define a rapid and simple test that would indicate the probable performance of a pretreated wood species in a hot-press drying process and the kiln schedule. The drying rate (mass/time) and the remaining mass of water were measured at different moisture intervals. The moisture of timber decreased rapidly and the drying rate was 3.7% per day in the early five days. The timbers were B grade after drying used the hot-press drying kiln in 16 days. The moisture content of timber reached 9.20% after the drying process with the standard deviation of 0.92%. The gradient of the moisture content was 3.40%. The moisture content standard deviation in the thickness of timber was 2.70% and the residual stress was 1.38%. The mechanical properties of impregnation wood improve significantly compared to the untreated wood. The basic density of impregnation wood improved by 17.1%, the over-dried density increased to 0.55 g·cm-3 from 0.49 g·cm-3. The scanning electron microscopy explained the wood modifier has been permeated into the wood fiber which reacted with the wood composition.

Calculation of Moisture Content and Drying Rate during Microwave Drying

2013 ◽  
Vol 423-426 ◽  
pp. 746-749
Author(s):  
Samad Khani Moghanaki ◽  
Behnam Khoshandam ◽  
Mohammad Hosein Mirhaj
Keyword(s):  
High Temperature ◽  
Moisture Content ◽  
Microwave Power ◽  
Operating Temperature ◽  
Irradiation Time ◽  
Microwave Drying ◽  
Drying Rate ◽  
Microwave Method ◽  
Drying Process ◽  
Drying Time

Convectional dryerswork at high temperature and usually lead to loss of quality for sensitivebiomaterial products (especially in nutrition). In this way the researchersfound the microwave power more effective and suitable for drying processes. Someof microwave drying advantages include the following: short drying time, highquality of product, low operating temperature, flexibility in producing widerange of products and easier process controlling. The article calculated themoisture content and drying rate during drying process. Microwave power, holdertray speed, dimension of samples, irradiation time were considered; under theseconditions experiments were done and the results show that microwave method hasmore advantages as comparing with convectional methods.

scholarly journals Model Matematis Hubungan antara Kadar Air Akhir Bahan dengan Variabel Proses Pengeringan pada Pneumatic Conveying Recirculated Dryer

2018 ◽  
Vol 38 (2) ◽  
pp. 217
Author(s):  
Abadi Jading ◽  
Nursigit Bintoro ◽  
Lilik Sutiarso ◽  
Joko Nugroho Wahyu Karyadi
Keyword(s):  
Mathematical Model ◽  
Moisture Content ◽  
Dimensional Analysis ◽  
Final Moisture Content ◽  
Sago Starch ◽  
Pneumatic Conveying ◽  
Drying Process ◽  
Vertical Pipe ◽  
The Mathematical Model ◽  
The Relationship

Flour drying could be conducted by using pneumatic conveying dryer (PCD) or flash dryer, but generally it is required a high vertical pipe. The high of vertical pipe may be replaced with a recirculation process to produce a required final moisture content of the material. This study had designed pneumatic conveying recirculated dryer (PCRD) to dryi of wet sago starch. Later, the design was used to determine a mathematical model of the relationship between the variables of drying process with final moisture content of the material. The purpose of this study was to develop a mathematical model of the relationship between the final moisture content of wet sago starch  with variables drying process and recirculation continuously in the pneumatic conveying recirculated dryer (PCRD) using dimensional analysis. Buckingham Phi Theorem methods of dimensional analysis was used to find the relationship variables that affect the final moisture content of wet sago starch on the PCRD machine. The mathematical model generated in this study is      The coefficient of determination (R2) of the mathematical model was 0.948, or 94.8 %, indicated that the model was valid to predict the final moisture content of wet sago starch in designing PCRD machines. While the sensitivity of the test results showed that the dimensionless product of the most influential are , , and . The model was applicable for drying wet sago starch or other starch material which is similat to the physical properties of wet sago starch. ABSTRAKPengeringan bahan-bahan tepung dapat dilakukan dengan pneumatic conveying dryer (PCD) atau flash dryer, namun umumnya memerlukan pipa vertikal yang cukup tinggi. Pipa vertikal yang tinggi dapat diganti dengan proses resirkulasi untuk menghasilkan kadar air akhir bahan yang disyaratkan. Pada penelitian ini telah dirancang pneumatic conveying recirculated dryer (PCRD) untuk mengeringkan pati sagu basah, serta dicari model hubungan matematis antara variabel-variabel proses pengeringan dengan kadar air akhir. Tujuan penelitian ini adalah mengembangkan model matematis hubungan antara kadar air akhir pati sagu basah dengan variabel-variabel proses pengeringan resirkulasi secara kontinyu pada pneumatic conveying recirculated dryer (PCRD) menggunakan analisis dimensi. Metode Buckingham Phi Theorem dalam analisis dimensi digunakan untuk mencari hubungan variabel-variabel yang berpengaruh terhadap kadar air akhir pati sagu basah pada mesin PCRD. Model matematis yang dihasilkan pada penelitian ini adalah      Nilai koefisien determinasi (R2) dari model matematis tersebut adalah 0,948 atau 94,8 %, menunjukkan bahwa model tersebut valid digunakan untuk memprediksi kadar air akhir pati sagu basah dalam merancang mesin PCRD. Sedangkan hasil uji sensitivitas menunjukkan bahwa dimensionless product yang paling berpengaruh adalah , , dan . Model tersebut berlaku untuk pengeringan pati sagu basah atau bahan-bahan tepung lainnya yang sifat fisiknya identik dengan pati sagu basah.

scholarly journals Drying kinetics of mango fruit using tray and oven dryer

2020 ◽  
Vol 3 (2) ◽  
pp. 51
Author(s):  
Nurhasmanina Norhadi ◽  
Ammar Mohd Akhir ◽  
Nor Roslina Rosli ◽  
Farid Mulana
Keyword(s):  
Moisture Content ◽  
Drying Kinetics ◽  
Drying Rate ◽  
Airflow Rate ◽  
Drying Process ◽  
Air Velocity ◽  
Mango Fruit ◽  
Drying Time ◽  
Different Temperatures ◽  
Kinetics Of

Drying is generally used to increase the shelf life of food products. In this context, mango fruit is used as a sample for the drying process because of its high commercial value and particularly high moisture content. The mango was sliced into few batches of sample with a size of 20 mm × 30 mm × 5 mm each. The experiments were conducted using tray and oven dryer at different temperatures of 40, 50 and 60 °C with a steady airflow rate of 1.3 m/s. The objectives are to study the effect of drying time, temperature and air velocity towards drying of mango fruit, to compare the physical characteristics of mango sample after drying and to determine the best drying kinetics model fitted to each tray and oven dryer. The results showed that the increase in drying time, temperature and air velocity would reduce the moisture content while at the same time, drying rate increased significantly. Tray dryer was found to be more effective than oven dryer because of higher drying rate with better product quality and appearance at the end. Furthermore, the gathered data were fitted into few widely used drying mathematical models and it was found that Henderson and Pabis model at 60°C is best suited for tray dryer whereas Page model at 40 °C is the best for oven dryer.

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