FLUIDIZATION OF MILLET AND PEA SEEDS

2021 ◽  
pp. 13-19
Author(s):  
ELENA L. BABICHEVA ◽  

One of the convective drying methods used to intensify the process of drying granular materials is the use of a device with a fl uidized bed. The essential advantages of fl uidized bed dryers are the uniform drying of all the particles in the bed and the ease of loading and unloading the material. The study goal was to conduct an experimental study of the hydrodynamics of the fl uidized bed of millet and pea seeds and the determination of the fi rst critical velocity (the rate of the beginning of fl uidization) based on these data. The authors took small (millet) and large (pea) seeds for the experiment. Based on the experimental data obtained, they constructed pseudo-liquefaction curves – ΔP = f (v) for millet and peas to determine the fi rst critical fl uidization rates (0.73 m/s for millet and 1.68 m/s for peas). The experimentally found values of the fi rst critical fl uidization rate were compared with the values calculated by the equations of O.M. Todes, Wen and Yu, and Grace. The study showed that all the equations provide an acceptable accuracy of calculations, but the accuracy of using the equation of O.M. Todes is somewhat higher. Therefore it can be primarily recommended for engineering analysis. The fi rst critical fl uidization rates, calculated according to the formula of O.M. Todes, were, accordingly: 0.69 m/s for millet and 1.60 m/s for pea. The calculation and experimental data on the fi rst critical fl uidization rates for millet and peas agree satisfactorily (the relative error for millet is 5.5%, for peas – 4.8%). The suffi ciently high accuracy of the fi rst critical fl uidization rates is explained by the correct geometric shape of the studied seeds, which is close to spherical. Therefore, the fi rst critical fl uidization speed of the studied seed material can be determined using the formula of O.M. Todes.

2017 ◽  
Vol 150 ◽  
pp. 153-162 ◽  
Author(s):  
Lin Zhi Lang ◽  
Wei Xiang ◽  
Wei Huang ◽  
De Shan Cui ◽  
Tom Schanz

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 927
Author(s):  
Weronika Tulej ◽  
Szymon Głowacki ◽  
Andrzej Bryś ◽  
Mariusz Sojak ◽  
Piotr Wichowski ◽  
...  

Determination of the mass diffusion coefficient for dried, inhomogeneous material is difficult as it depends on the drying agent temperature and the moisture content and physical structure of the material. The paper presents a method for efficient determination of the water diffusion coefficient for wood solid cuboids dried using convective drying methods. In this work, the authors define a theoretical dependence of the Fourier number on reduced water content in a convectively dried cuboidal solid, based on a simplified theoretical solution of the diffusion equation for such a body. The material for drying included shoots of common osier, robinia (false acacia), multiflora rose, and energy poplar, dried at temperatures of 40, 50, 60, 70, and 80 °C, in free convection. The obtained results differ from the theoretically anticipated changes of the coefficient.


Molecules ◽  
2019 ◽  
Vol 24 (4) ◽  
pp. 764 ◽  
Author(s):  
Jacek Łyczko ◽  
Klaudiusz Jałoszyński ◽  
Mariusz Surma ◽  
Klaudia Masztalerz ◽  
Antoni Szumny

True lavender (Lavandula angustifolia Mill.) is a widely used flavoring and medicinal plant, which strong aroma is mainly composed of linalool and linalyl acetate. The most valuable parts of the plant are the flowers, however leaves are also abundant in volatile constituents. One of the main factors responsible for its quality is the preservation procedure, which usually comes down to a drying process. For this reason an attempt to verify the influence of various drying methods (convective drying, vacuum-microwave drying and combined convection pre-drying with vacuum-microwave finishing drying) on the quality of true lavender leaves was carried out by determination of the volatile constituents profile by solid-phase microextraction (SPME) coupled with GC-MS technique. Total essential oil (EO) content was also verified. The study has revealed that the optimal drying method is strongly dependent on the purpose of the product. For flavoring properties convective drying at 60 °C is the most optimal method, while the best for preserving the highest amount of EO is vacuum-microwave drying at 480 W. Furthermore, SPME analysis had shown that drying may increase the value of true lavender leaves by significantly affecting the linalool to linalyl acetate to camphor ratio in the volatile profile.


Author(s):  
Ivelin Kostov

In the work brought some experimental data of kinematic parameters of movement of cars forced idle, as the software product was used to diagnose 900 ATS, which recorded kinematic parameters of vehicle. On the basis of the conducted experimental research results are shown tabulated and analysed.


1992 ◽  
Vol 57 (9) ◽  
pp. 1905-1914
Author(s):  
Miroslav Bleha ◽  
Věra Šumberová

The equilibrium sorption of uni-univalent electrolytes (NaCl, KCl) in heterogeneous cation exchange membranes with various contents of the ion exchange component and in ion exchange membranes Ralex was investigated. Using experimental data which express the concentration dependence of equilibrium sorption, validity of the Donnan relation for the systems under investigation was tested and values of the Glueckauf inhomogeneity factor for Ralex membranes were determined. Determination of the equilibrium sorption allows the effect of the total content of internal water and of the ion-exchange capacity on the distribution coefficients of the electrolyte to be determined.


Author(s):  
Emre Kahramanoglu ◽  
Silvia Pennino ◽  
Huseyin Yilmaz

The hydrodynamic characteristics of the planing hulls in particular at the planing regime are completely different from the conventional hull forms and the determination of these characteristics is more complicated. In the present study, calm water hydrodynamic characteristics of planing hulls are investigated using a hybrid method. The hybrid method combines the dynamic trim and sinkage from the Zarnick approach with the Savitsky method in order to calculate the total resistance of the planing hull. Since the obtained dynamic trim and sinkage values by using the original Zarnick approach are not in good agreement with experimental data, an improvement is applied to the hybrid method using a reduction function proposed by Garme. The numerical results obtained by the hybrid and improved hybrid method are compared with each other and available experimental data. The results indicate that the improved hybrid method gives better results compared to the hybrid method, especially for the dynamic trim and resistance. Although the results have some discrepancies with experimental data in terms of resistance, trim and sinkage, the improved hybrid method becomes appealing particularly for the preliminary design stage of the planing hulls.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vali Rasooli Sharabiani ◽  
Mohammad Kaveh ◽  
Roozbeh Abdi ◽  
Mariusz Szymanek ◽  
Wojciech Tanaś

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.


Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 560
Author(s):  
Alexandra Carvalho ◽  
Mariana C. F. Costa ◽  
Valeria S. Marangoni ◽  
Pei Rou Ng ◽  
Thi Le Hang Nguyen ◽  
...  

We show that the degree of oxidation of graphene oxide (GO) can be obtained by using a combination of state-of-the-art ab initio computational modeling and X-ray photoemission spectroscopy (XPS). We show that the shift of the XPS C1s peak relative to pristine graphene, ΔEC1s, can be described with high accuracy by ΔEC1s=A(cO−cl)2+E0, where c0 is the oxygen concentration, A=52.3 eV, cl=0.122, and E0=1.22 eV. Our results demonstrate a precise determination of the oxygen content of GO samples.


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