scholarly journals Mass and color kinetics of foamed and non foamed grape concentrate during convective drying process: A comparative study

2014 ◽  
Vol 6 (4) ◽  
pp. 48-67 ◽  
Author(s):  
Gupta Kalika ◽  
S. Alam M.
Keyword(s):  
Comparative Study ◽  
Convective Drying ◽  
Drying Process ◽  
Kinetics Of

scholarly journals Kinetics Of Fruit Crops Drying With Instant Pressure Release

2020 ◽  
Vol 02 (10) ◽  
pp. 45-54
Author(s):  
Rustamov E.S. ◽  
◽  
Djuraev Kh.F. ◽  
Gafurov K.Kh. ◽  
◽  
...  
Keyword(s):  
Energy Supply ◽  
Infrared Heating ◽  
Convective Drying ◽  
Drying Process ◽  
Fruit Crops ◽  
Technological Parameters ◽  
Pressure Impact ◽  
Instantaneous Pressure ◽  
Kinetics Of

The article covers results of research of drying process of apricot fruits by the method of three-stage energy supply. The main stages of drying have been defined, including: pulsed infrared heating, instantaneous pressure impact, convective drying. Optimal technological parameters of energy supply in the process of drying apricot fruits at each stage have been developed. The choice of the method for the experimental determination of the drying speed by the parameters of the drying agent for the capillary-porous material is substantiated. The sequence of changes in moisture content in a given material under the influence of a three-stage energy supply is described. The conditions for drying fruits are established and the values of the drying speed in the first period for various methods of energy supply have been selected.

scholarly journals Investigation of the Kinetics of the Drying Process of Composite Pellets on a Convective Drying Stand

2021 ◽  
Vol 22 (6) ◽  
pp. 159-166
Author(s):  
Zhanna Petrova ◽  
Yurii Sniezhkin ◽  
Vadym Paziuk ◽  
Yuliia Novikova ◽  
Anton Petrov
Keyword(s):  
Convective Drying ◽  
Drying Process ◽  
Composite Pellets ◽  
Kinetics Of

Modeling Thin Layer Drying Kinetics, Moisture Diffusivity and Activation Energy of Hazelnuts during Microwave-Convective Drying

2017 ◽  
Vol 14 (2) ◽  
Author(s):  
Narjes Malekjani ◽  
Zahra Emam-Djomeh ◽  
Seyed Hassan Hashemabadi ◽  
Gholam Reza Askari
Keyword(s):  
Activation Energy ◽  
Microwave Power ◽  
Moisture Diffusivity ◽  
Drying Kinetics ◽  
Convective Drying ◽  
Drying Method ◽  
Drying Process ◽  
Dominant Effect ◽  
Thin Layer Drying ◽  
Kinetics Of

AbstractThe effects of microwave-convective drying as an efficient drying method, on drying kinetics of hazelnuts were studied. Drying experiments were conducted at three temperature (40, 50 and 60°C) and microwave power (0, 450 and 900 W) levels. The moisture ratio and the temperature of the hazelnuts were recorded during the drying. The results showed that microwave power had a more dominant effect than drying air temperature. Mathematical modeling was performed in order to predict the moisture changes during drying process. It was concluded that two term and Midilli et al. models were the best models to predict the drying kinetics of hazelnut in different conditions. The effective moisture diffusivities varied from 3.80327×10‒8to 1.71233×10‒6m2/s and had an increasing polynomial relationship with temperature and microwave power. The activation energy was also between 15.61675 and 41.0053 kJ/mol with a second-order relationship with microwave power.

scholarly journals RATIONAL DRYING MODES FOR RAPE SEEDS

2021 ◽  
pp. 99-103
Author(s):  
Vadym Paziuk ◽  
Eugenia Shemanska ◽  
Dasha Paziuk
Keyword(s):  
Experimental Data ◽  
Experimental Studies ◽  
Acid Number ◽  
Convective Drying ◽  
Coolant Temperature ◽  
Drying Process ◽  
Temperature Range ◽  
Automatic Program ◽  
Processing Information ◽  
Kinetics Of

Studies on finding rational regimes for drying rapeseed based on drying kinetics and qualitative characteristics are presented. The value of the acid number of oil and laboratory germination of rapeseed on the 7th day of germination were taken as a qualitative characteristic. Experimental studies of the kinetics of the rapeseed drying process were performed on a convective drying stand using an automatic program for collecting and processing information, which makes it possible to obtain more accurate experimental data. According to the obtained experimental data with the help of an automatic program for collecting and processing information, graphs of the process kinetics from the influence of the coolant temperature are constructed. The presented graphs show the drying curves and drying speed curves that characterize the drying process that takes place during the period of falling drying speed. The study of the kinetics of the drying process of rapeseed in a single-stage mode at coolant temperatures of 50 - 80°C showed that for better quality it is necessary to use low-temperature modes. The acid number of oil in this temperature range does not change significantly and is 1.03 - 1.8 mg / g of oil. These values of the acid number of the oil correspond to the normative value. The greatest effect on the germination of rapeseed is observed from the temperature of the coolant. Increasing the temperature by 10 ° C in the temperature range from 50 to 80 ° C reduces the germination of the material. According to laboratory studies, we determined the drying regime of 50 ° С with a germination of 97% to be the most expedient and rational. All other drying regimes significantly reduce the germination of rapeseed and can not be recommended, as the germination value is less than the state standard of Ukraine 2240-93.

scholarly journals MODELING OF CONVECTIVE DRYING PROCESS DISPERSE MATERIAL IN GRAVITY-MOVING MONOLAYER AT MICROKINETIC LEVEL

2021 ◽  
pp. 55-59
Author(s):  
А.А. Шевцов ◽  
Т.Н. Тертычная ◽  
С.С. Куликов
Keyword(s):  
Differential Equations ◽  
Disperse Material ◽  
Convective Drying ◽  
Thermal Mass ◽  
Drying Process ◽  
Single Particles ◽  
Transfer Coefficients ◽  
Simplifying Assumptions ◽  
Flax Seeds ◽  
Kinetics Of

Нелинейность дифференциальных уравнений тепломассопереноса А.В. Лыкова и сложность в экспериментальном определении неизвестных коэффициентов, входящих в них, не позволяют получить аналитического решения, что обусловлено зависимостью коэффициентов переноса от температуры и влагосодержания материала. Известные аналитические решения получены лишь для тел канонической формы (пластина, цилиндр, шар). Однако эти решения громоздки и сложны по структуре, что сдерживает их практическое применение. Для построения математической модели процесса конвективной сушки в работе сформулированы упрощающие допущения: форма частицы рассматривалась в виде неограниченного цилиндра; пренебрегалось аксиальной влагопроводностью, термодиффузией, теплопроводностью отдельной частицы. Применение теоретических методов микрокинетики непрерывной сушки дисперсных материалов, основанных на описании кинетики сушки единичных частиц, сформулированных упрощений, начальных и граничных условий позволили получить систему дифференциальных уравнений в безразмерном виде, описывающую процесс сушки единичной частицы при прямоточно-противоточном продувании агента сушки через гравитационно-движущийся монослой высушиваемого материала. Данная система уравнений является упрощенной (не учитываются температурные градиенты, термодиффузия, распределенность источника теплоты в самой частице) и решена методом Рунге-Кутта четвертого порядка точности. Приводится графическая интерпретация результатов моделирования на примере сушки семян льна, получившего широкое применение в производстве технического масла. Погрешность моделирования не превышает 12,5 %. The nonlinearity of the differential equations of thermal mass transfer of A.V. Lykov and the difficulty in experimentally determining the unknown coefficients included in them do not allow us to obtain an analytical solution, which is due to the dependence of transfer coefficients on the temperature and moisture content of material. Known analytical solutions are obtained only for canonical bodies (plate, cylinder, ball). However, these solutions are cumbersome and complex in structure, which hinders their practical application. To build a mathematical model of the convective drying process, simplifying assumptions are formulated in the work: the shape of the particle was considered in the form of an unlimited cylinder; neglected axial WLA, thermodiffusion, thermal conductivity of an individual particle. The use of theoretical methods of microkinetics of continuous drying of dispersed materials, based on the description of the kinetics of drying of single particles, formulated simplifications, initial and boundary conditions, made it possible to obtain a sys-theme of differential equations in dimensionless form, describing the process of drying of a single particle during direct-flow countercurrent blowing of a drying agent through a gravitational-moving monolayer of a high-sutured material. This system of equations is simplified (temperature gradients, thermodiffusion, distribution of the heat source in the particle itself are not taken into account) and solved by the Runge-Kutt method of the fourth order of accuracy. A graphical interpretation of the simulation results is given on the example of drying of flax seeds, which has been widely used in the production of technical oil. The mode error does not exceed 12.5 %.

scholarly journals Investigation of low-temperature drying modes plant capillary-porous materials spherical shape

2018 ◽  
pp. 7-14
Author(s):  
V.М. Pazyuk
Keyword(s):  
Porous Materials ◽  
Heat Carrier ◽  
Experimental Studies ◽  
Spherical Shape ◽  
Convective Drying ◽  
Drying Rate ◽  
Drying Process ◽  
Exchange Processes ◽  
Low Temperature Drying ◽  
Kinetics Of

The results of experimental studies of the drying of capillary-porous materials of spherical shape from the influence of the temperature of the heat carrier are given.Spherical granules with a diameter of 2,2 mm were taken to determine the rational modes of drying of capillary-porous materials. For a better evaluation of the nature of the drying process, experimental design studies were carried out on a convective drying stand in an elementary layer.The program of automatic collection and processing of information allows obtaining data on changes in the mass and temperature of the sample during the removal of moisture, and also performs calculations of kinetics of drying in absolute and relative coordinates. This makes it possible to obtain and compare the kinetic and velocity characteristics of colloid capillary-porous materials drying faster, more accurately and reliably.By the method of Krasnikov V.V. the kinetics of drying of capillary-porous materials of spherical shape with a diameter of 2,2 mm with construction of a generalized drying curve with determination and calculation of drying coefficients is considered.The generalized curve of drying rate is constructed and obtained, which allows us to generalize the process of drying of a capillary-porous spherical material. Also, get the formula and determine the overall length of the drying process through the drying rate for each heat treatment.When comparing the values of the process length obtained by experimental studies and determined by the calculations, the experimental error from the calculation does not exceed 3%.The analysis of heat-mass-exchange processes of drying by means of calculations of temperature coefficient b, Rebinder Rb criterion, heat flow q and coefficient of heat transfer α from the influence of heat carrier temperature has been carried out.

scholarly journals Two-dimensional mathematical model for simulation of the drying process of thick layers of natural materials in a conveyor-belt dryer

2017 ◽  
Vol 21 (3) ◽  
pp. 1369-1378 ◽  
Author(s):  
Dusko Salemovic ◽  
Aleksandar Dedic ◽  
Nenad Cupric
Keyword(s):  
Mathematical Model ◽  
Conveyor Belt ◽  
Convective Drying ◽  
Drying Process ◽  
Moist Air ◽  
Automated Control ◽  
Linear Differential ◽  
The Mathematical Model ◽  
Kinetics Of ◽  
Thick Layers

This paper presents the mathematical model and numerical analysis of the convective drying process of thick slices of colloidal capillary-porous materials slowly moving through conveyor-belt dryer. A flow of hot moist air was used as drying agent. The drying process has been analyzed in the form of a 2-D mathematical model, in two directions: along the conveyor and perpendicular on it. The mathematical model consists of two non-linear differential equations and one equation with a transcendent character and it is based on the mathematical model developed for drying process in a form of a 1-D thin layer. The appropriate boundary conditions were introduced. The presented model is suitable for the automated control of conveyor-belt dryers. The obtained results with analysis could be useful in predicting the drying kinetics of potato slices and similar natural products.

scholarly journals Drying Characteristics of Dracocephalum moldavica Leaves: Drying Kinetics and Physicochemical Properties

Processes ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 509 ◽  
Author(s):  
Stanisław Rudy ◽  
Dariusz Dziki ◽  
Beata Biernacka ◽  
Andrzej Krzykowski ◽  
Mariusz Rudy ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Essential Oils ◽  
Chemical Properties ◽  
Total Content ◽  
Convective Drying ◽  
Vacuum Drying ◽  
Drying Process ◽  
Total Flavonoids Content ◽  
Physical And Chemical ◽  
Kinetics Of

The aim of the study was to determine the effect of the method and temperature of the sublimation, vacuum and convective drying process on the kinetics of dehydration of the Moldovan dragonhead leaves, as well as on the physical and chemical properties, such as color coordinates, total content of phenolic compounds, antioxidant capacity, total monomeric anthocyanins content, total flavonoids content and content of essential oils. It was shown that the kinetics of the sublimation and vacuum drying process are best described by the logarithmic and Page models. Sublimation and vacuum drying were characterized by comparable process times. An increase in drying temperature caused a decrease in the content of phenolic compounds and antioxidant activity of the dried material and a significant change in the composition of essential oils. The lowest brightness of the dried material and the lowest color saturation was found after sublimation drying at 20 °C. The highest dried material quality was found in case of convective and sublimation drying at 20 °C.

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