scholarly journals Analysis of the process of immersion of kernels in liquids with different specific mass

2019 ◽  
Vol 20 (4) ◽  
pp. 407-419 ◽  
Author(s):  
V. E. Saitov ◽  
V. G. Farafonov ◽  
A. V. Saitov

In a grain pile there is material other than grain including poisonous ergot sclerotia. Grain and sclerotia of ergot by linear dimensions and speed of soaring have similar characteristics. Complete separation of grain from ergot by these properties in a single process is impossible. Cleaning seeds from ergot sclerotia with the specific mass less than the specific mass of grain is possible in a salt solution. To mechanize the separation of ergot sclerotia from rye seeds by the wet method, there is an urgent need in the development of an appropriate device. Under study was an immersion in water (ρzh = 1.0∙103 kg/m3 ) and aqueous solutions of sodium chloride (NaCl) with a specific mass ρzh = 1.09∙103 and 1.15∙103 kg/m3 of individual rye grains with their specific mass ρz = 1.2...1.5∙103 kg/m3 , length lz = 5.0...10.0 10-3 m, width в = 1.4...3.6∙10-3 m and thickness δ = 1.2...3.5∙10-3 m. Theoretical studies were carried out on the basis of mathematical modeling methods using the laws of hydrodynamics, which were confirmed by experimental studies with winter rye grains of the Falenskaya 4 variety with a specific mass ρz = 1.1...1.3 103 kg/m3 , length lz = 5.0...8.0∙10-3 m, width в = 1.4...3.6∙10-3 m and thickness δ = 1.2...3.5∙10-3 m. It has been established that the calculated values of the immersion velocity of cylindrical kernels and spheroidal kernels in comparison with the experimental values in water (ρzh = 1.0∙103 kg/m3 ) is not more than 2%, and in aqueous solutions of sodium chloride (NaCl) the specific mass ρzh = 1.09∙103 and 1.15∙103 kg/m3 – 7 and 10%, respectively. This approach to determining the speed of immersion of grain in liquid can be used in the development of the machine for cleaning grain according to specific mass using wet method to substantiate its structural and technological parameters.

Author(s):  
Vasily A Sysuev ◽  
Viktor Е. Saitov ◽  
Vyacheslav G. Farafonov ◽  
Aleksey V. Saitov

Introduction.When harvesting grain crops, various trash and harmful impurities come to the combine bunker together with grains. These harmful impurities include egot sclerotia, which are poisonous. Various modern grain cleaning machines do not provide for complete separation of ergot sclerotia from grains, because of the closeness of their linear dimensions (width, thickness and length) and speed of soaring. Cleaning seeds from ergot sclerotia having the density less than density of grain, is possible in an aqueous solution of salt. For the mechanization of the allocation of sclerotium ergot from rye seeds by a wet method, the urgent issue is the development of a device for cleaning grain material. Materials and Methods.The immersion of separately taken rye grains in water (ρzh = 1,0 ∙ 103 kg/m3) and aqueous solutions of sodium chloride (NaCl) with density ρzh = 1,09 ∙ 103 kg/m3 and 1,15 ∙ 103 kg/m3. The ellipsoid is taken as the geometric model of the grains. Theoretical studies were performed for the grain density ρz from 1,2 ∙ 103 kg/m3 to 1,5 ∙ 103 kg/m3, lengths lz from 5,0 ∙ 10–3 m to 10,0 ∙ 10–3 m, width b from 1,4 ∙ 10–3 m to 3,6 ∙ 10–3 m, and thickness δ from 1,2 ∙ 10–3 m to 3,5 ∙ 10–3 m based on the methods of mathematical modelling using the laws of hydrodynamics. For practical experiments, there was chosen the gains of the winter rye variety Falenskaya 4 having the gain density ρz from 1,1 ∙ 103 kg/m3 to 1,3 ∙ 103 kg/m3, length lz from 5,0 ∙ 10–3 m to 8,0 ∙ 10–3 m, width b from 1,4 ∙ 10–3 m to 3,6 ∙ 10–3 m, and thickness δ from 1,2 ∙ 10–3 m to 3,5 ∙ 10–3 m. Results. The speed ʋz and duration tп of grain immersion in liquids are main parameters taken into account when developing a machine for cleaning the grain material from ergot sclerotia with a wet method. The values of these quantities determine the structural and technological parameters of the machine under developing. To determine these parameters, it is necessary to take into account the geometric shapes of the grains, which have a large variety. An ellipsoid with a small 2cz = δ, an average 2bz = b and a large 2az = lz axes is proposed as the closest to the shape of the grain. From the basic law of the dynamics of the grain movement in liquids of various densities ρzh a formula was obtained for determining its velocity, the calculated values for which are consistent with the experimental data obtained. Discussion and Conclusion. It is established that the calculated values of the speed of grain immersion in liquids of different density are comparable with the experimental values of the same order. They are close and differ by no more than 10 %. This approach to determining the speed of grain immersion in a liquid can be used in developing a machine for cleaning a grain material with the wet method to substantiate its structural and technological parameters.


Author(s):  
Eugene Berezhenko ◽  
Maria Pankiv ◽  
Jan Jobbagy ◽  
Bogdan Berezhenko

Reduction of energy consumption, which creates hygienic root crops, is achieved with the use of expanded boxes of new technologies and improved pick-up modules, which is an urgent scientific task. Tests of the energy-saving method of growing plants are given and what is more, the scheme of experimental installations (put into operation of the plant harvesting module) and the methods of experimental field factors used in roots have been provided. Analytical and empirical dependencies are obtained, which characterize the change of the second feed and the specific mass of the cut and chopped knife of the rotary saw cutter, depending on the velocity of the module, the yield capacity and the density of chicory root crops plantation. The specific mass of the plant harvested from 3 rows of root crops are, respectively, in the range from 17 to 36 (kg/s) and from 19 to 27 (kg/m2). The results of the experimental studies were processed using Statistics 10, the confidence level P = 0.95, the Fisher F-criterion F = 100.8> Frit and the t-alpha criterion t = 2.05. Based on the graphical constructions it was established that the discrepancy between theoretical and experimental values of the second feed and the specific gravity of the ridge ranges from 10 to 15 (%).


2021 ◽  
Vol 24 (6) ◽  
pp. 1232-1242
Author(s):  
I. N. Madyshev ◽  
V. E. Zinurov ◽  
A. V. Dmitriev ◽  
Xuan Vinh Dang ◽  
G. R. Badretdinova

The purpose of the study is to conduct experimental studies of oil -water emulsion separation in a rectangular separator in the range of velocities along the device working area from 1.43 to 2.5 m/s. The efficiency of emulsion separation is determined by an experimental method based on measuring the density of a two-phase liquid, provided that the density of each component of the mixture is previously determined. The authors propose to use a device with U-shaped elements to increase its performance when separating oil-water emulsions. The device under study including two rows of U-shaped elements consists of one complete separation stage. The authors have conducted experimental studies of the device with U-shaped elements on the "oil-water" system, during which the efficiency of emulsion separation was evaluated. It was detemined that the proposed device provides the highest efficiency of emulsion separation of 68% when the diameter of the holes intended for the exit of the heavy phase equals to 2.5 mm in the range of emulsion velocities from 1.43 to 2.5 m/s. The conducted experimental studies will allow to use a turbulence model for calculation in the programs like Ansys Fluent or FlowVision, which will most adequately describe the separation process of similar emulsions. The experiments have proved the possibility of obtaining high values of efficiency. Therefore, the correct selection of technological parameters (average flow rate, concentration) and the size of the characteristic elements of the proposed device will allow to specify the design of a rectangular separator, for example, to calculate the number of stages to achieve the required separation efficiency or to determine the size of the separation elements.


Author(s):  
O. Yu. Kichigina

At production of stainless steel expensive alloying elements, containing nickel, are used. To decrease the steel cost, substitution of nickel during steel alloying process by its oxides is an actual task. Results of analysis of thermodynamic and experimental studies of nickel reducing from its oxide presented, as well as methods of nickel oxide obtaining at manganese bearing complex raw materials enrichment and practice of its application during steel alloying. Technology of comprehensive processing of complex manganese-containing raw materials considered, including leaching and selective extraction out of the solution valuable components: manganese, nickel, iron, cobalt and copper. Based on theoretical and experiment studies, a possibility of substitution of metal nickel by concentrates, obtained as a result of hydrometallurgical enrichment, was confirmed. Optimal technological parameters, ensuring high degree of nickel recovery out of the initial raw materials were determined. It was established, that for direct steel alloying it is reasonable to add into the charge pellets, consisting of nickel concentrate and coke fines, that enables to reach the through nickel recovery at a level of 90%. The proposed method of alloying steel by nickel gives a possibility to decrease considerably steel cost at the expense of application of nickel concentrate, obtained out of tails of hydrometallurgical enrichment of manganese-bearing raw materials, which is much cheaper comparing with the metal nickel.


The work of multilayer glass structures for central and eccentric compression and bending are considered. The substantiation of the chosen research topic is made. The description and features of laminated glass for the structures investigated, their characteristics are presented. The analysis of the results obtained when testing for compression, compression with bending, simple bending of models of columns, beams, samples of laminated glass was made. Overview of the types and nature of destruction of the models are presented, diagrams of material operation are constructed, average values of the resistance of the cross-sections of samples are obtained, the table of destructive loads is generated. The need for development of a set of rules and guidelines for the design of glass structures, including laminated glass, for bearing elements, as well as standards for testing, rules for assessing the strength, stiffness, crack resistance and methods for determining the strength of control samples is emphasized. It is established that the strength properties of glass depend on the type of applied load and vary widely, and significantly lower than the corresponding normative values of the strength of heat-strengthened glass. The effect of the connecting polymeric material and manufacturing technology of laminated glass on the strength of the structure is also shown. The experimental values of the elastic modulus are different in different directions of the cross section and in the direction perpendicular to the glass layers are two times less than along the glass layers.


1984 ◽  
Vol 49 (5) ◽  
pp. 1061-1078 ◽  
Author(s):  
Jiří Čeleda ◽  
Stanislav Škramovský

Based on the earlier paper introducing a concept of the apparent parachor of a solute in the solution, we have eliminated in the present work algebraically the effect which is introduced into this quantity by the additivity of the apparent molal volumes. The difference remaining from the apparent parachor after substracting the contribution corresponding to the apparent volume ( for which the present authors suggest the name metachor) was evaluated from the experimental values of the surface tension of aqueous solutions for a set of 1,1-, 1,2- and 2,1-valent electrolytes. This difference showed to be independent of concentration up to the very high values of the order of units mol dm-3 but it was directly proportional to the number of the free charges (with a proportionality factor 5 ± 1 cm3 mol-1 identical for all studied electrolytes). The metachor can be, for this reason, a suitable characteristic for detection of the association of ions and formation of complexes in the solutions of electrolytes, up to high concentrations where other methods are failing.


1931 ◽  
Vol 6 (1) ◽  
pp. 1-11 ◽  
Author(s):  
J. F. LOGAN

As a contribution to the chemistry of muscle tissue, the solubility of the protein of haddock muscle in aqueous solutions of sodium chloride and neutral potassium phosphate, respectively, was determined. The results are expressed in tabular form and graphically in the form of solubility curves. A water-soluble protein and also a salt-soluble protein were isolated from dialyzed haddock muscle by extraction methods. These proteins were obtained in a comparatively pure condition by precipitation from solution in the region of their isoelectric points.


2006 ◽  
Vol 240 (2) ◽  
pp. 186-196 ◽  
Author(s):  
Andreas Hüther ◽  
Xiaoping Xu ◽  
Gerd Maurer

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