The intensification of dehydration process of pectin-containing raw materials

The process of intensifying dehydration of pectin-containing raw materials by using centrifugation with simultaneous application of low-frequency oscillations to the working container creates an electroosmotic effect in unilateral diffusion to improve the filtration process. It is established that to reduce the technological resistance in the presented methods; it is necessary to create a fluidized bed of products due to the oscillating motion of the working capacity. An experimental vibration unit has been developed to determine the rational parameters of the vibrocentric moisture removal process using the electroosmotic effect. It is proved that the complex of the designed equipment provides consecutive carrying out of three-stage vibration filtration-convective drying of high-moisture production by an alternation of action of a stream of the heat carrier, an electromagnetic field, low-frequency fluctuations. According to the research results, the dependences of the kinetics of the moisture diffusion process on the electric field strength are obtained; frequency of electric current and duty cycle of pulses, which allowed to optimize the process parameters according to the criteria of minimizing energy consumption. It was found that the processing time to achieve the desired humidity with the application of vibration, filtration, and electroosmotic effect was twice less than for filtration drying in a fixed bed. In combination with the noted physical and mechanical factors, the proposed technology improves the technical and economic parameters of the studied process.

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Research of drying kinetics of prepared wheat flour

FOOD RESOURCES ◽

10.31073/foodresources2021-16-20 ◽

2021 ◽

Vol 9 (16) ◽

pp. 212-220

Author(s):

Liubomyr Khomichak ◽

◽

Inha Kuznietsova ◽

Svetlana Vysotska ◽

Sergiy Tkachenko ◽

...

Keyword(s):

Moisture Content ◽

Wheat Flour ◽

Raw Materials ◽

Control Sample ◽

Raw Material ◽

Convective Drying ◽

Kinetic Dependence ◽

Vital Functions ◽

Kinetic Coefficients ◽

Kinetics Of

Introduction. Processing of grain raw material with influence on starch or albumens by application of heat treatment creates the variety of functional properties of a product and is perspective in the modern terms vital functions of man. Research methods and methods. The flour obtained from wheat of the Ascanian wheat and from wheat of the soft varieties: Sophia ("sweet wheat"), Blond (soft) and Chornobrova (enriched with micro- and macronutrients) were used in the study. Thermal modification of flour samples was carried out in a convective manner. The control sample for determining the quality indicators is obtained in industrial conditions, extruded wheat flour produced by LLC "AS groups, LTD". Research results. The obtained kinetic dependence shows the gradual loss of moisture standards with different speed which accordingly influences on duration of drying. The moisture content of the drying agent most affects the intensity at the initial stage of the constant drying rate. With an increase in the moisture content of the coolant, the period of constant drying increases and the amount of evaporated moisture increases during this period. With the subsequent removal of moisture from raw materials, the degree of influence of this parameter on the intensity decreases. The nature of the drying curves is the same and the recommended process for obtaining modified flour is the process duration of 300 minutes or 5 hours. It was determined microscopically, that the samples of dried wheat flour have a purpose and are partially destroyed by starch granules and amorphization of biocomposite materials. Based on the data on the kinetics of drying flour samples, the kinetic coefficients and values of the critical moisture content for drying wheat flour were calculated, which is 1.18-1.30 %. It was determined that for the sensorial indicators the obtained samples have indicators characteristic of the varietal characteristics of wheat, from which the flour was taken. In terms of physical and chemical parameters, the modified wheat flour samples are not inferior to the well-known industrial sample of extruded flour. Conclusions. Use of flour, obtained from the wheat with different correlation of amilose and amylopectin, positively influences on a technological process and allows to extend the assortment of modified starch products, and accordingly, food products. Kinetics of the convective drying standards of the flour is investigated. Researches showed that a it is physically modified flour obtained from the different sorts of the soft wheat is not inferior in quality to the extruded wheat flour.

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Kinetic Study of Various Chars Steam Gasification

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.1460 ◽

2007 ◽

Vol 5 (1) ◽

Cited By ~ 3

Author(s):

Frédéric Paviet ◽

Olivier Bals ◽

Gérard Antonini

Keyword(s):

Raw Materials ◽

Fixed Bed ◽

Steam Gasification ◽

Fixed Bed Reactor ◽

Municipal Solid Wastes ◽

Kinetics Parameters ◽

Successful Design ◽

Kinetic Expression ◽

Gasification Reaction ◽

Kinetics Of

Gasification is an attractive technology for waste thermal treatment. The successful design and modelling of a gasifier requires reliable kinetic data. The purpose of this work is to study the steam gasification kinetics of chars produced by municipal wastes pyrolysis. The municipal solid wastes (MSW) are modelled as a mixture of four organic constituents: paper, wood, plastics, and vegetables. The various char samples are obtained by pyrolysis of each waste constituent, in a fixed bed reactor at 1000°C, in order to minimize their volatile content and thus, to eliminate any subsequent devolatilization of the carbonaceous residues. These chars are used as raw materials in steam gasification experiments. The gasification studies are performed on each char separately, in a tubular kiln at various temperatures (900°C, 950°C and 1000°C) and various vapour pressures (0.2 bar, 0.5 bar and 0.7 bar). The gases produced are analysed by gas chromatography in order to determine the gasification kinetics. The kinetics parameters, with respect to H2O, together with the influence of the char's physical properties are experimentally determined. A kinetic expression for the gasification reaction, based on the random pore model is deduced. It is shown that the char resulting from the pyrolysis of MSW constituents, essentially paper, wood and vegetables have the same gasification kinetics. On the contrary, the plastic char steam gasification kinetic appears to be significantly slower.

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Evaluation of a Moisture Diffusion Model for Analyzing the Convective Drying Kinetics of Lavandula x allardii Leaves

Computation ◽

10.3390/computation9120141 ◽

2021 ◽

Vol 9 (12) ◽

pp. 141

Author(s):

Vasileios Chasiotis ◽

Dimitrios Tzempelikos ◽

Andronikos Filios

Keyword(s):

Diffusion Model ◽

Moisture Transfer ◽

Variable Temperature ◽

Moisture Diffusion ◽

Drying Kinetics ◽

Convective Drying ◽

Water Evaporation ◽

Drying Rate ◽

Computationally Efficient ◽

Kinetics Of

In the present case study, a moisture diffusion model is developed to simulate the drying kinetics of Lavandula x allardii leaves for non-stationary convective drying regimes. Increasing temperature profiles are applied over the drying duration and the influence of temperature advancing rates on the moisture removal and the drying rate is investigated. The model assumes a one-dimensional moisture transfer under transient conditions, which occurs from the leaf center to the surface by liquid diffusion due to the concentration gradient developed by the surface water evaporation caused by the difference of water vapor partial pressure between the drying medium and the leaf surface. A numerical solution of Fick’s 2nd law is obtained by an in-house code using the finite volume method, including shrinkage and a variable temperature-dependent effective moisture diffusion coefficient. The numerical results have been validated against experimental data for selected cases using statistical indices and the predicted dehydration curves presented a good agreement for the higher temperature advancing rates. The examined modeling approach was found stable and can output, in a computationally efficient way, the temporal changes of moisture and drying rate. Thus, the present model could be used for engineering applications involving the design, optimization and development of drying equipment and drying schedules for the examined type of non-stationary drying patterns.

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Method for The Primary Processing of Silkworm Cocoons (Bombyx Mori)

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.a5089.119119 ◽

2019 ◽

Vol 9 (1) ◽

pp. 4562-4565 ◽

Cited By ~ 6

Keyword(s):

Bombyx Mori ◽

Elastic Waves ◽

Raw Materials ◽

Low Frequency ◽

Ir Radiation ◽

Primary Processing ◽

Low Frequency Oscillations ◽

Infrared Rays ◽

Electromechanical Drive ◽

Scale Test

The article discusses the results of an experimental study of the process of primary processing of silkworm cocoons (Bombyx mori). During the study, the possibilities of the primary processing of silkworm cocoons using elastic waves with infrared radiation were examined. The Tashkent State Technical University has developed a mechanism for generating low-frequency oscillations due to an electromechanical drive to pallets. In the laboratory of the department, a full-scale test was carried out for the primary processing of silkworm cocoons (Bombyx mori). Studies were carried out to determine the parameters as temperature and time of primary processing of silkworm cocoons in 5 times repetition. The results of the experiments are the primary processing of live cocoons (Bombyx mori) in the amount of one hundred pieces with infrared rays, the effects of vibration and elastic waves (the distance between the tube distributing infrared rays and raw materials is 10 cm, the duration of the process is 5 minutes). The study revealed that, as silkworm cocoons processed in the temperature range at 65-70 0С using vibration waves were moderate for 3-5 minutes and for 10 days at a temperature of 38-42 0С the cocoons continued to dry to 10-12% of the cane humidity. The use of elastic waves in the processing of cocoons proceeded 5-10% lower relative to the processing using vibratory waves. The obtained results, the experiments confirm that when applying vibration and IR radiation accelerates the process of primary processing of silkworm cocoons. The study found the optimum temperature and time for the primary processing of silkworm cocoons. Due to briefly temporary processing, the final product is improved.

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Modeling of convective drying kinetics of Pistachio kernels in a fixed bed drying system

Thermal Science ◽

10.2298/tsci110307040b ◽

2013 ◽

Vol 17 (3) ◽

pp. 839-846 ◽

Cited By ~ 9

Author(s):

Asım Balbay ◽

Ömer Şahin ◽

Hakan Ülker

Keyword(s):

Initial Moisture Content ◽

Fixed Bed ◽

Effective Diffusivity ◽

Drying Kinetics ◽

Convective Drying ◽

Air Temperatures ◽

Drying Behavior ◽

Drying System ◽

Drying Conditions ◽

Kinetics Of

Drying kinetics of Pistachio kernels (PKs) with initial moisture content of 32.4% (w.b) was investigated as a function of drying conditions in a fixed bed drying system. The drying experiments were carried out at different temperatures of drying air (40, 60 and 80?C) and air velocities (0.05, 0.075 and 0.1 m/s). Several experiments were performed in terms of mass of PKs (15g and 30g) using a constant air velocity of 0.075 m/s. The fit quality of models was evaluated using the determination coefficient (R2), sum square error (SSE) and root mean square error (RMSE). Among the selected models, the Midilli et al model was found to be the best models for describing the drying behavior of PKs. The activation energies were calculated as 29.2 kJ/mol and effective diffusivity values were calculated between 1.38 and 4.94x10-10 m2/s depending on air temperatures.

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