scholarly journals Design and Performance Evaluation of a Solar Assisted Heat Pump Dryer Integrated with Biomass Furnace for Red Chilli

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
M. Yahya
Keyword(s):  
Moisture Content ◽  
Heat Pump ◽  
Drying Kinetics ◽  
Coefficient Of Determination ◽  
Mean Bias Error ◽  
Bias Error ◽  
Drying Time ◽  
Sun Drying ◽  
Kinetics Of ◽  
Drying Chamber

The performance of a solar assisted heat pump dryer integrated with biomass furnace has been designed and evaluated for drying red chillies, and drying kinetics of red chillies were evaluated. The red chillies were dried from 22 kg with moisture content of 4.26 db to moisture content of 0.08 db which needed 11 hours, with the average drying chamber temperature, drying chamber relative humidity, and an air mass flow rate of 70.5°C, 10.1%, and 0.124 kg/s, respectively, while the open sun drying needed 62 hours. Compared to open sun drying, this dryer yielded 82% saving in drying time. The drying rate, the specific moisture extraction rate, and thermal efficiency of the dryer were estimated in average to be about 1.57 kg/h, 0.14 kg/kWh, and 9.03%, respectively. Three mathematical models, the Newton, Henderson-Pabis, and Page models, were fitted to the experimental data on red chillies dried by solar assisted heat pump dryer integrated with biomass furnace and open sun drying. The performance of these models was evaluated by comparing the coefficient of determination (R2), mean bias error (MBE), and root mean-square error (RMSE). The Page model gave the best results for representing drying kinetics of red chillies.

scholarly journals Drying of MalaysianCapsicum annuumL. (Red Chili) Dried by Open and Solar Drying

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Ahmad Fudholi ◽  
Mohd Yusof Othman ◽  
Mohd Hafidz Ruslan ◽  
Kamaruzzaman Sopian
Keyword(s):  
Root Mean Square ◽  
Coefficient Of Determination ◽  
Mean Bias Error ◽  
Bias Error ◽  
Solar Drying ◽  
Mean Square ◽  
Drying Time ◽  
Sun Drying ◽  
65 H ◽  
Mean Square Errors

This study evaluated the performance of solar drying in the Malaysian red chili (Capsicum annuumL.). Red chilies were dried down from approximately 80% (wb) to 10% (wb) moisture content within 33 h. The drying process was conducted during the day, and it was compared with 65 h of open sun drying. Solar drying yielded a 49% saving in drying time compared with open sun drying. At the average solar radiation of 420 W/m2and air flow rate of 0.07 kg/s, the collector, drying system, and pickup demonstrated efficiency rates of approximately 28%, 13%, and 45%, respectively. Evaporative capacity ranged from 0.13 to 2.36 kg/h, with an average of 0.97 kg/h. The specific moisture extraction rate (SMER) of 0.19 kg/kWh was obtained. Moreover, the drying kinetics ofC. annuumL. were investigated. A nonlinear regression procedure was used to fit three drying models. These models were compared with experimental data on red chilies dried by open sun drying and those dried by solar drying. The fit quality of the models was evaluated using their coefficient of determination (R2), mean bias error, and root-mean-square error values. The Page model resulted in the highestR2and the lowest mean bias and root-mean-square errors.

scholarly journals Drying kinetics of Hyola 430 hybrid canola (Brassica napus L.) seeds

2020 ◽  
pp. 1623-1629
Author(s):  
Lílian Moreira Costa ◽  
Osvaldo Resende ◽  
Daniel Emanoel Cabral de Oliveira ◽  
José Mauro Guimarães Carvalho ◽  
Sarah Gabrielle Sousa Bueno ◽  
...  
Keyword(s):  
Moisture Content ◽  
Mathematical Models ◽  
Effective Diffusion ◽  
Initial Moisture Content ◽  
Information Criteria ◽  
Drying Kinetics ◽  
Coefficient Of Determination ◽  
Statistical Parameters ◽  
Drying Time ◽  
Kinetics Of

This work aimed to study the drying kinetics of canola seeds, fit mathematical models and obtain the effective diffusion coefficient. Canola seeds with initial moisture content of 0.3653 (decimal, d.b.) were subjected to drying in a forced ventilation oven at temperatures of 40, 60, 80 and 100 °C and relative humidity of 37.15, 16.93, 8.35, 4.41 and 2.47%, respectively. The samples were dried on trays without perforations, containing approximately 77 g, in three replicates. A final moisture content of 0.080 ± 0.004 (decimal, d.b.) was established to determine the drying curves and fit the mathematical models. The mathematical models were selected considering the mean estimated error, chi-square, coefficient of determination, mean relative error, and Akaike (AIC) and Bayesian (BIC) information criteria. Drying time decreased with increasing temperature. Based on the best values of the statistical parameters and together with the Akaike and Bayesian information criteria, the Page model was selected to represent the drying kinetics of canola seeds. The effective diffusion coefficients showed magnitudes between 0.153x10-11 and 1.221x10-11 (m2 s-1), and their values increased with temperature increase, being described by the Arrhenius equation, with activation energy of 33.94 kJ mol-1, an important piece of information to consider when designing drying equipment

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.

Thin-Layer Mathematical Modeling of Turmeric in Indirect Natural Conventional Solar Dryer

2020 ◽  
Vol 142 (4) ◽  
Author(s):  
Masnaji R. Nukulwar ◽  
Vinod B. Tungikar
Keyword(s):  
Mathematical Modeling ◽  
Moisture Content ◽  
Thin Layer ◽  
Air Velocity ◽  
Drying Time ◽  
Sun Drying ◽  
Solar Dryer ◽  
Air Temperatures ◽  
Drying Efficiency ◽  
Kinetics Of

Abstract The objective of this study is to find an optimized thin-layer mathematical model suitable for drying kinetics of turmeric. Turmeric has a high moisture content which necessitates effective drying. A 10 kg, sample batch, of turmeric was dried in a solar dryer. Drying air temperatures and air velocity were observed in the range of 55 °C–68 °C and 0.7 m/s–1.4 m/s, respectively, in the drying experiments. It is seen that the moisture content of the turmeric is reduced from 77% to 11.93% in 22 h when compared with open sun drying, which required 60 h for the same reduction in the moisture content. Scheffler dish was used to generate steam for the dryer. Seven thin-layer mathematical models, cited in the literature, had been used for the study. These models were applied for different trays placed in the dryer. The result of the research and experimentation showed that the Page model fits best for drying in the steam-based dryer and open sun drying. Experimental results showed 63.33% saving in drying time, and the drying efficiency was found as 29.85%. Uncertainty in the drying efficiency was observed as 0.67%. Experimental investigation and the findings from the mathematical modeling are presented in this paper.

Drying Kinetics Evaluation of Solid Red Bricks

2015 ◽  
Vol 3 ◽  
pp. 119-134
Author(s):  
E. Barreira ◽  
J.M.P.Q. Delgado ◽  
V.P. de Freitas
Keyword(s):  
Moisture Content ◽  
Molecular Diffusion ◽  
Moisture Transfer ◽  
Drying Kinetics ◽  
Drying Process ◽  
Drying Time ◽  
First Order ◽  
First Order Kinetics ◽  
Kinetics Of ◽  
Best Fit

Moisture is one of the most deteriorating factors of buildings. The moisture content depends on hygroscopic equilibrium between buildings materials and environment, which is determined by the drying and wetting rate of masonry. So, the moisture content is not only determined by the water that is absorbed by the material, but also by the amount of water that is evaporated under favourable conditions, which is described by the drying process.This work presents the results of an experimental evaluation of the drying kinetics of solid red brick, considering the bulk moisture transfer. The drying kinetics was assessed considering different environment conditions (air temperature and humidity). The experimental results showed that the drying flux is extremely dependent of temperature and relative humidity in the first stage of the drying process. The values obtained were between 0.025 kg/m2h (T=15oC and RH=80%) and 0.135 kg/m2h (T=30oC and RH=50%), for the worst and better drying ambient conditions.Different first-order kinetics models, available in the literature, were adjusted to describe the drying process and estimate the equilibrium moisture content of the samples. The results point that Midilli et al. model allows the best fit and that the drying time constant is strongly affected by the drying air conditions. It was also estimated the apparent molecular diffusion coefficient for solid red brick samples and its variation with temperature.

scholarly journals Modelagem matemática para a descrição da cinética de secagem do fruto da palma (Opuntia fícus indica)

2016 ◽  
Vol 11 (1) ◽  
pp. 01
Author(s):  
A. E. Santos ◽  
G. M. V. Martins ◽  
M. F. C. S. Canuto ◽  
J. E. D. Vieira Segundo ◽  
R. D. Almeida
Keyword(s):  
Thin Layer ◽  
Drying Kinetics ◽  
Coefficient Of Determination ◽  
Font Size ◽  
Drying Time ◽  
Palm Fruit ◽  
Opuntia Ficus Indica ◽  
Thin Layer Drying ◽  
Kinetics Of ◽  
Background Image

<p>O presente trabalho teve como objetivo estudar a secagem em camada fina do fruto da palma (<em>Opuntia fícus indica</em>) nas temperaturas de 50, 60 e 70 °C em estufa com circulação forçada de ar. Foram empregados os modelos matemáticos de Aproximação da difusão, Logaritmico, Midilli e Page. Como critério de avaliação utilizou-se o coeficiente de determinação e o desvio quadrático médio (). Mediante os resultados obtidos observou-se que o aumento da temperatura diminuiu o tempo de secagem do fruto. Dentre os modelos aplicados o Logarítmico apresentou os maiores valores de coeficiente de determinação R² e os menores valores de DQM para a faixa de temperatura e espessura estudadas.</p><p class="MsoNormal" style="margin-bottom: 0.0001pt; text-align: center;" align="center"><strong><em><span style="font-size: 14pt; font-family: 'Times New Roman', serif; background-image: initial; background-attachment: initial; background-size: initial; background-origin: initial; background-clip: initial; background-position: initial; background-repeat: initial;" lang="EN-US">Mathematical modeling for description of the pulp drying kinetics of palm fruit (Opuntia fícus indica)</span></em></strong></p><p class="MsoNormal" style="margin-bottom: 0.0001pt;"><span style="font-size: 9pt; font-family: 'Times New Roman', serif; background-image: initial; background-attachment: initial; background-size: initial; background-origin: initial; background-clip: initial; background-position: initial; background-repeat: initial;" lang="EN-US"> </span></p><p> </p><p class="MsoNormal" style="margin-bottom: 0.0001pt; text-align: justify;"><strong><span style="font-size: 10pt; font-family: 'Times New Roman', serif; background-image: initial; background-attachment: initial; background-size: initial; background-origin: initial; background-clip: initial; background-position: initial; background-repeat: initial;" lang="EN-US">Abstract</span></strong><span style="font-size: 10pt; font-family: 'Times New Roman', serif; background-image: initial; background-attachment: initial; background-size: initial; background-origin: initial; background-clip: initial; background-position: initial; background-repeat: initial;" lang="EN-US">: This work was developed with the aimed of to study ing the thin layer drying of palm fruit pulp oiti at temperatures of 122, 140 and 158 °Fahrenheit in an oven with forced air circulation. For the representation of the drying kinetics of thin-layer were used mathematical  models of the diffusion approximation, logarithmic, and Midilli Kucuk and Page, and as a criterion for evaluating these we used the coefficient of determination and the deviation quadratic mean (DQM). From tThe results obtained showed that the increase in temperature decreases the drying time of the palm fruit. Among the models applied to Logarithmic the had the highest R2 values and lower values of DQM for the temperature and layer thickness range studied.</span></p><br /><strong></strong><p class="MsoNormal" style="margin-bottom: 0.0001pt; text-align: center;" align="center"> </p>

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.

scholarly journals Drying characteristics of wood of invasive tree species growing in an urban environment

Les/Wood ◽  
2019 ◽  
Vol 68 (2) ◽  
pp. 31-43 ◽  
Author(s):  
Denis Plavčak ◽  
Željko Gorišek ◽  
Aleš Straže ◽  
Maks Merela
Keyword(s):  
Moisture Content ◽  
Wood Species ◽  
Tree Species ◽  
Black Locust ◽  
Robinia Pseudoacacia ◽  
Urban Environments ◽  
Drying Kinetics ◽  
Horse Chestnut ◽  
Drying Time ◽  
Kinetics Of

Non-native tree species are increasingly growing in urban environments, where they are exposed to cultivation and pruning measures, and in many cases their growth becomes uncontrolled, even invasive. In such cases the structure of the wood is more heterogeneous, with more tyloses, discolorations and decay, and higher moisture content. The drying of such wood is more demanding and cannot rely on the standard drying schedules. Therefore, the drying kinetics of the boards (thickness 22 mm, 28 mm and 46 mm) of three wood species (black locust – Robinia pseudoacacia; box elder – Acer negundo and horse chestnut – Aesculus hippocastanum) were analysed at 20 °C and 40 °C. Additionally, the drying quality was assessed by determining the moisture content gradient, drying stresses and presence of typical drying defects. In the drying tests the moisture content gradients were relatively low in all species, so no high drying stresses were generated. Due to the expected high risk of collapse, careful drying of green maple was needed, to prevent board twisting when a pronounced number of knots and greater fibre deviation occurred. Half-drying times indicated the longer drying of thicker black locust boards, and very careful drying of maple. We confirmed the usability of the half-drying time to compare the drying kinetics of different wood species and assortments.

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 Evaluation of Drying Kinetics and Activation Energy of Oyster Mushroom (Pleurotus ostreatus)

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
A.S Ajala ◽  
A.D. Ogunsola ◽  
T.A. Akanbi
Keyword(s):  
Activation Energy ◽  
Pleurotus Ostreatus ◽  
Social Scientist ◽  
Drying Kinetics ◽  
Oyster Mushroom ◽  
Coefficient Of Determination ◽  
Mean Bias Error ◽  
Bias Error ◽  
Average Temperature ◽  
Thin Layer Drying

Oyster mushroom (Pleurotus ostreatus) is a fungus which easily deteriorates after harvest and hence, there is need to make it stable by reducing its moisture content to a lower level after harvest. In this study, fresh oyster mushrooms were dried using three modes of drying: sun at an average temperature of 32 oC, solar at an average temperature of 40 o C and tunnel dryer at 50 o C. Kinetics of moisture drying was modelled using Fick’s second law of diffusion which is generally applicable to thin-layer drying of agricultural products. Six models namely Henderson and Pabis, Logarithms, Newton, Page, Two Terms and Midilli Kucuk were employed for the drying kinetics. Nonlinear regression analysis was carried out using Statistical Package for Social Scientist (SPSS 16.0 version) to fit the experimental data. The reliability of the models was tested using some statistical criteria such as coefficient of determination (R2), reduced chi- square (χ2), Mean Bias Error (MBE) and Root Mean Square Error (RMSE). The model which had the best fit was chosen to represent the drying behaviour of oyster mushroom. The drying pattern was observed to be in the single falling rate period in the entire drying modes. The values of R2 ranged from 0. 0.933-0.988, χ2(2.4E-06-0.044), MBE (-7.6E-4-0.044) and RMSE (7.8E-4-0.201). Effective moisture diffusivity for samples dried in the sun, solar and tunnel were 1.19 E-11m2/s, 1.21 E-11m2/s and 1.59 E-11m2/s, respectively. Two Term model best described drying behavior of oyster mushroom during tunnel drying and the activation energy of the model was 64.9kJ/mol.

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