scholarly journals Development of an Automated Solar Powered Hot-air Supplemented Dryer

2019 ◽  
pp. 1-14
Author(s):  
O. Taiwo Aduewa ◽  
S. Ajiboye Oyerinde ◽  
P. Ayoola Olalusi
Keyword(s):  
Solar Energy ◽  
Moisture Content ◽  
Initial Moisture Content ◽  
Climatic Conditions ◽  
Solar Drying ◽  
Drying Time ◽  
Drying Temperature ◽  
Hot Air ◽  
Solar Powered ◽  
Drying Chamber

The world is facing two major challenges: one is to meet the exponential growing demand for energy particularly in developing and underdeveloped countries and other is to deal with global, regional and local environmental impacts resulting from supply and use of conventional energy. The cost-effective technology for solar drying that can be easily adopted among the rural farmers of developing countries needs to be developed in areas where solar energy is abundantly available. As cheap as the solar energy could be, there are associated problems with the stability of the energy for different purposes due to instability of climatic conditions. For this research, a solar powered hot-air supplemented dryer (SPHSD) with a capacity of 20 kg of sliced yam was designed and developed. The SPHSD has three sections which are solar collector chamber, drying chamber and hot-air supplement chamber which is powered with two 150-watt solar panel and a 200 amps solar battery for continuous operation during bad weather. All data were logged digitally for accuracy and test was done using yam slices. Difference in drying time and stability in drying temperature was evaluated using SPHSD and indirect solar dryer. The result shows stability of temperature in the drying chamber when SPHSD was used while the drying temperature fluctuates throughout the indirect solar drying test period. Drying experiment was conducted for 481 minutes (between 0910 hrs to 1713 hrs) reducing the moisture content from 71.91%, 72.1% and 72.8% to 27.95%, 25.78% and 28.23% for MC1, MC2 and MC3in wet basis respectively. Drying experiment was conducted for 832 minutes (between 0901 hrs to 2257 hrs) reducing the moisture content from initial moisture content levels of 72.66%, 71.48% and 71.48% to 13.47%, 12.53% and 12.54% for MC1, MC2 and MC3in wet basis respectively.

An Indirect Passive Solar Dryer for Drying

2011 ◽  
Vol 367 ◽  
pp. 517-524
Author(s):  
A. F. Alonge ◽  
O. O. Oniya
Keyword(s):  
Moisture Content ◽  
Initial Moisture Content ◽  
Solar Drying ◽  
Drying Time ◽  
Sun Drying ◽  
Two Samples ◽  
Drying System ◽  
Average Size ◽  
Local Materials ◽  
Drying Chamber

A solar drying system designed on the principles of convective heat flow, constructed from local materials was employed in drying yam (Dioscorea Alata). A glass collector having an efficiency of about 0.63 was used along with an absorber for absorbing the heat energy. The drying chamber consisted of drying trays. A chimney fitted at the top centre of the drying chamber enhanced airflow. Air passing through the collector heated up and dried the foodstuff in the drying chamber. The latitude of Ilorin is 8.26oN and the collector angle could be varied . 56o C, 41o C and 71o C were obtained as the maximum attainable temperatures for the drying chamber, ambient and collector respectively. Two samples of yam chips, each weighing 1560g and having an average size of 1cm thick, were dried both inside the dryer and outside the dryer within its surrounding. The initial moisture content of the yam was 70.3% (wet basis) and its final moisture content was 9% (wet basis).The result was compared to natural sun drying. It was observed that the drying time was reduced from 52 hours for sun drying to 45 hours for solar drying. The total cost of the construction was 6, 105 Naira.

scholarly journals Energy Analysis of a Hybrid Solar Dryer for Drying Coffee Beans

2020 ◽  
Vol 9 (1) ◽  
pp. 131-139
Author(s):  
Suherman Suherman ◽  
Hasri Widuri ◽  
Shelyn Patricia ◽  
Evan Eduard Susanto ◽  
Raafi Jaya Sutrisna
Keyword(s):  
Moisture Content ◽  
Solar Collector ◽  
Energy Analysis ◽  
Initial Moisture Content ◽  
Solar Drying ◽  
Drying Method ◽  
Drying Time ◽  
Solar Dryer ◽  
Coffee Beans ◽  
Drying Chamber

In this study, hybrid solar drying of coffee beans was performed, and energy analysis was carried out, to assess the system’s performance, in terms of energy efficiency, compared to solar drying and the open sun drying method. The dryer has three compartments: solar collector for collecting solar radiation, drying chamber, and a Liquid Petroleum Gas burner, which acted as an auxiliary heater to assist the thermal energy. The drying chamber has four trays for placing the dried product. The initial moisture content of coffee beans was 54.23% w.b and was reduced to the final moisture content between 11-12% w.b. The coffee beans dried faster when subjected to the solar hybrid drying method, compared to other methods, with the dryer temperature of 40°C, 50°C, and 60°C. Results indicated that the coffee beans’ drying times varied from 10 to 14 hours. However, at temperature 50°C and 60°C for the 1st tray, the water content was reduced more rapidly compared to the other tray. From the results of this study, we can see the different efficiency of solar collector that shows of 54.15% at variable temperature 60°C for drying time 12:00 to 14:00 p.m for hybrid solar drying and for the solar drying process is 50.07% at the range of drying time 12:00 to 14:00 p.m. Mathematical modelling shows that Page model is the most suitable for describing the coffee beans’ drying behaviour using a hybrid solar dryer. The effective diffusivity values found in this experiment are all in the acceptable range for most agricultural products. ©2020. CBIORE-IJRED. All rights reserved

scholarly journals Influence of Different Hot Air Drying Temperatures on Drying Kinetics, Shrinkage, and Colour of Persimmon Slices

Foods ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 101 ◽  
Author(s):  
Senadeera ◽  
Adiletta ◽  
Önal ◽  
Di Matteo ◽  
Russo
Keyword(s):  
Moisture Content ◽  
Quadratic Model ◽  
Drying Process ◽  
Air Velocity ◽  
Hot Air Drying ◽  
Drying Time ◽  
Air Drying ◽  
Drying Characteristics ◽  
Drying Temperature ◽  
Hot Air

Drying characteristics of persimmon, cv. “Rojo Brillante”, slabs were experimentally determined in a hot air convective drier at drying temperatures of 45, 50, 55, 60, and 65 °C at a fixed air velocity of 2.3 m/s. It was observed that the drying temperature affected the drying time, shrinkage, and colour. Four empirical mathematical models namely, Enderson and Pabis, Page, Logarithmic, and Two term, were evaluated in order to deeply understand the drying process (moisture ratio). The Page model described the best representation of the experimental drying data at all investigated temperatures (45, 50, 55, 60, 65 °C). According to the evaluation of the shrinkage models, the Quadratic model provided the best representation of the volumetric shrinkage of persimmons as a function of moisture content. Overall, higher drying temperature (65 °C) improved the colour retention of dried persimmon slabs.

Multi-Objective Optimization and Quality Evaluation of Short- and Medium-Wave Infrared Radiation Dried Carrot Slices

2019 ◽  
Vol 15 (8) ◽  
Author(s):  
Qinqin Chen ◽  
Huihui Song ◽  
Jinfeng Bi ◽  
Ruijuan Chen ◽  
Xuan Liu ◽  
...  
Keyword(s):  
Moisture Content ◽  
Infrared Radiation ◽  
Quality Evaluation ◽  
Color Parameter ◽  
Rehydration Ratio ◽  
Carotene Content ◽  
Drying Time ◽  
Drying Temperature ◽  
Hot Air ◽  
Surface Method

AbstractOptimum technology and quality evaluation of short- and medium-wave infrared radiation (SMIR) dried carrot slices were studied. Effects of drying temperature, drying time and infrared power of SMIR drying on the moisture content, color parameter and β-carotene content of dehydrated carrot slices were investigated. The experimental data were well predicted by a modified second-order polynomial model. Drying temperature and drying time had significant effects on moisture content, color parameter and β-carotene content. However, infrared power only showed significant effect on the moisture content. Response surface method (RSM) was used for optimization of SMIR drying of carrot slices, and the optimum condition was found as drying time of 50 min, infrared power of 1125 W, and drying temperature of 70 °C. SMIR dried products were proved to be favorable by comparing with hot-air dried ones due to its higher rehydration ratio (6.89) and β-carotene content (462.48 μg/g).

scholarly journals Effect of Drying Temperatures on Chemical compounds and Antioxidant properties of Vitex negundo leaves

2020 ◽  
Vol 13 (2) ◽  
pp. 94-102
Author(s):  
Hada Masayu I ◽  
A Fauziah ◽  
K Y Pin ◽  
Safwan K Ihsan ◽  
M Shalini ◽  
...  
Keyword(s):  
Moisture Content ◽  
Phenolic Content ◽  
Antioxidant Properties ◽  
Initial Moisture Content ◽  
Total Phenolic ◽  
Slight Reduction ◽  
Vitex Negundo ◽  
Drying Time ◽  
Drying Temperature ◽  
Time Required

The effect of drying temperature on the leaves of Vitex negundo was determined. Three levels of temperatures (40, 50 and 60°C) were used in the presented study. The initial moisture content of the leaves was 69.98%. Continuous drying at the above mentioned temperature levels was conducted to determine the drying time required to achieve equilibrium moisture content. The quality of dried leaves was evaluated based on the quantity of agnuside, a major compound in V. negundo using HPLC analysis. The fastest drying of the leaves was achieved at 60°C, followed by at 50°C, but HPLC results showed that dried V. negundo suffered at 40% reduction in agnuside content when drying at 60°C as compared to at 40°C. Slight reduction of agnuside was found in the sample dried at 50°C as compared to at 40°C. Whereas, antioxidant results showed that V. negundo leaves have significant level of phenolic content and the effect of drying at higher temperature has significantly reduce the amount of phenolics in V. negundo leaves. Total phenolic content of V. negundo leaves was highest at 50 °C drying temperature. Based on the findings of this work, the best convection oven drying condition for V. negundo leaves was at 50°C with the highest agnuside concentration of 502.224 mg/L and phenolic content of 286.7 ± 11.0 mg GAE/100g.

scholarly journals Drying kinetics and thin layer modeling of ogi produced from six maize varieties at varying soaking period and drying temperature

Food Research ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 431-440
Author(s):  
O.T. Bolaji ◽  
P.A. Adepoju ◽  
E.O. Adelana ◽  
B.S. Adesina
Keyword(s):  
Activation Energy ◽  
Moisture Content ◽  
Thin Layer ◽  
Research Work ◽  
Initial Moisture Content ◽  
Moisture Diffusivity ◽  
Drying Kinetics ◽  
Drying Time ◽  
Drying Temperature ◽  
Maize Varieties

The drying kinetics of ogi produced from six varieties of maize at varying soaking period (12, 24 and 36 hrs) and drying temperature of 40, 50 and 60oC, respectively were studied. Seven common thin layer models were evaluated, and the best models were selected. The moisture content of ogi decreased with increased drying temperature and drying time while the drying rate increased with an increase in drying temperature and decreased with an increase in drying time. Logarithmic and two term models best fitted about 40.77% (22 samples each). However, where two term models were selected best, the R2 values ranged from 0.9858-0.99999999, χ 2 = 0.03715-0.000412, RMSE = 0.02206-0.0000677, unlike Logarithmic model that ranged from 0.8876-0.9964, χ 2 = 0.07045-0.001447, RMSE = 0.1084-0.01098. There was no definite pattern for effective moisture diffusivity (Deff) and Activation energy (Ea). This research work strongly suggests that the drying process was predominantly in the falling rate period (FRP) and was significantly affected by the change in temperature and moisture gradient. The activation energy obtained for ogi at varying soaking period and drying temperature ranged from 2.58-12.00 kJ/mol (A4Y), 7.72-44.95 kJ/mol (A4W), 14.53-35.88 kJ/mol (S7Y), 6.02-20.10 kJ/mol (D2Y), 14.024- 45.31 kJ/mol (DIY) and 19.34-64.22 kJ/mol (T3W). It was obviously indicated in this research that the soaking period had less or no impact on the drying behavior of ogi compared with the influence of drying temperature, drying time and initial moisture content.

scholarly journals Pengaruh kecepatan udara dan massa gabah terhadap kecepatan pengeringan gabah menggunakan pengering terfluidisasi

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
S. Syahrul ◽  
M. Mirmanto ◽  
S. Romdani ◽  
S. Sukmawaty
Keyword(s):  
Moisture Content ◽  
Initial Moisture Content ◽  
National Standards ◽  
Drying Process ◽  
Air Velocity ◽  
Drying Time ◽  
Grain Processing ◽  
Grain Moisture ◽  
Time Required ◽  
Drying Chamber

Grain processing does not meet the actual grain harvests. This is due to the unsuitable drying process. Milling grain entrepreneurs and farmers in Indonesia are currently conducting a drying process under the sun. Based on the National Standards Body (BSN), grain moisture content must be at 14% to maintain the grain at high qualities. The purpose of this study is to determine the effect of velocity and grain mass variations on drying times. The grain used in this study contains an initial moisture content of 22% ± 0.5%. The grain is dried by inserting it into the drying chamber and varying the air velocities and grain mass. The air velocities used are 4 m/s, 5 m/s, 6 m/s and the variations of the grain mass are 1 kg 2 kg and 3 kg. The results show that increasing the air velocity decreases the drying time. On the other hand, when the grain mass is increased, the drying time elevates. The air velocity and mass of the grain that results in the fastest drying time are 6 m/s and 2 kg. The time required for achieving the water content of 13.6% is 30 menit. At the air velocity of 4 m/s, and the grain masses of 1 kg, 2 kg, and 3 kg, to achieve moisture contents of 13.4%, 13.5% and 13.4% the drying time needs 50 minutes.

The Drying Characteristic of Biomass with High Moisture Content

2011 ◽  
Vol 130-134 ◽  
pp. 401-405
Author(s):  
Xiao Qiang Wang ◽  
Shi Ye Feng ◽  
Shu Hua Su ◽  
Zhi Bo Zhang ◽  
Qiang Lu ◽  
...  
Keyword(s):  
Moisture Content ◽  
Rice Husk ◽  
Initial Moisture Content ◽  
High Moisture Content ◽  
High Moisture ◽  
Drying Time ◽  
Drying Characteristics ◽  
Drying Temperature ◽  
Bed Thickness

This paper presents the drying characteristics of rice husk and cornstalk with high moisture content at fixed temperatures. Experiments were performed in an oven drier, to reveal to the effects of initial moisture content, bed thickness and drying temperature on the biomass drying characteristics. The results indicated that the drying time was decreased as the rising of the drying temperature, and increased along with the initial moisture content and bed thickness. Moreover, the risk husk was easy to be dried than the cornstalk.

scholarly journals Design and Analysis of a Novel Drying Chamber in Indirect Forced Convection Solar Drying

2020 ◽  
Vol 9 (9s) ◽  
pp. 11-16
Keyword(s):  
Energy Efficiency ◽  
Forced Convection ◽  
Solar Collector ◽  
Ambient Air ◽  
Drying Rate ◽  
Solar Drying ◽  
Drying Time ◽  
Hot Air ◽  
Drying Chamber ◽  
Effective Distribution

Long drying time and less control on drying parameters in natural convection drying give way to forced convection indirect solar drying. In forced convection drying, an external blower supplies ambient air into the solar collector. The incoming air gets heated inside the collector and this air then flows into the drying chamber where the product to be dried is kept. The hot air absorbs the moisture from the raw crops and exits through the chimney. Along with the temperature and humidity of incoming air, its distribution inside the drying chamber is also important in the process of drying. The drying rate and quality can be improved if these parameters are under control in forced convection solar drying. In this paper, design and analysis of a novel drying chamber are presented to improve the performance and energy efficiency of solar drying with effective distribution of air inside the chamber. The variation of velocity with respect to different positions inside the drying chamber is also studied numerically.

Performance of a Solar Drying System Driven by a Hybrid Power System

2012 ◽  
Vol 455-456 ◽  
pp. 139-146
Author(s):  
Hao Zhong ◽  
Zhi Min Li ◽  
Tong Wu ◽  
Ming Jiu Yu ◽  
Run Sheng Tang
Keyword(s):  
Power System ◽  
Early Stage ◽  
Initial Moisture Content ◽  
Agricultural Products ◽  
Solar Drying ◽  
Test Results ◽  
Drying Time ◽  
Drying System ◽  
Drying Chamber

To increase the production and improve the quality of dried agricultural products, a new drying system with a hybrid driving power system was developed and tested. The system with total collector area of 100m2 is consisted of 10 drying units and each of them is consisted of 5 identical air collectors and a greenhouse-like drying chamber. Each of collectors in the system is equipped with a DC fan, powered by either 120W solar modules or a 300W wind turbine, and an AC fan, directly powered by the electricity from grid. Such drying system can operate in all time of any day and avoid any possible spoilage of dried products as found in conventional solar dryers due to the formation of mould on the surface of dried materials in the events of consecutive rainy days. Field test for the drying of 9 fruits was conducted from November to December in 2005. The results indicated that the system was very effective for the drying of fruits and the solar drying time for most of the materials to be investigated was only one third of that required in the natural sun drying. Test results also showed that the nocturnal ventilation of drying chambers at the early stage of drying exercise was necessary for materials with high initial moisture content in order to further shorten the solar drying time.

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