Перегляд за Автор "Vasylenko, Sergei"

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Analysis of the energy efficiency of heat exchangers of sugar Industry
(2013) Samiilenko, Serhii; Vasylenko, Sergei; Shutyuk, Vitaliy
The article describes thermodynamic methods as well as optimization methods of heating and heat exchanging engineering system of sugar industry. The authors suggest noncyclic approach to the analysis of efficiency of heat exchanging apparatus, the basis of which is irrefutable fact that irreversibility as physical reason of inefficiency of technical heat engineering systems really exists.
Analysis of the process of formation of N-nitrosodimethylamine in brewer’s malt
(2014) Shutyuk, Vitaliy; Bessarab, Alexander; Haralanova, Temenuzhka; Vasylenko, Sergei
The article deals with the issues of carcinogenic substances formation in the manufacture of beer. It is shown that the basic technological process, that influences the N-NDMA accumulation in beer, is brewer's malt drying. The determining factor, influencing the N-NDMA content in malt, is the concentration of nitrogen dioxide at the entrance to malt layer. In the course of research, drying conditions typical for dryers of «Latvian Academy of Agriculture» type, one-deck dryers and apparatuses on malt manufacturing in combined way were secured. The measuring of nitric oxides was carried out by the means of gas- analyzer of 645 HL 20 type, the principle of operation of which is based on chemiluminescent method of determination of nitric oxide. More intensive absorption of nitrogen dioxide were observed during the first stage (constant speed) of drying due to the large number of free moisture presence in malt – a good nitrogen dioxide absorbent. The concentration of nitrogen dioxide in the drying agent has the greatest impact on intensification of N-NDMA formation processes in malt, that is recorded in all experiments. That is why in order to achieve guaranteed quality of the product, one should establish the limit of concentration of NDMA in malt equaling 15 mcg/kg. Drying of malt with drying agent with concentration of nitric dioxide up to 0,4 mg/m3 guarantees concentration of NDMA lower than this limit. This concentration should be limiting in the field of development of modern heating vent systems.
Entropy analysis of heat exchanging appliances
(2013) Samiilenko, Serhii; Vasylenko, Sergei; Shutyuk, Vitaliy
The article describes thermodynamic methods as well as optimization methods of heating and heat exchanging engineering system of sugar industry. The authors suggest noncyclic approach to the analysis of efficiency of heat exchanging apparatus, the basis of which is irrefutable fact that irreversibility as physical reason of inefficiency of technical heat engineering systems really exists. Thermodynamic analysis, which was mentioned in the article, assumes determination of measure of irreversibility of processes in the apparatus and energetic efficiency of apparatus in the whole with the help of exceptionally entropy. The measures taken to improve energetic efficiency of apparatus of saccharine factory on the example of the first group of juice heating in front of evaporator system using the given methodology, were fully analyzed.
Innovative solutions to research in drying technology of food raw materials
(2013) Shutyuk, Vitaliy; Vasylenko, Sergei; Bessarab, Alexander; Vasyliv, Volodymyr
Reasons over of growing interest are brought in the processes of drying, and also some aspects of co-operation of industry and scientific university collectives in embodiment and application. The tendencies of research of processes of drying, that appear on the joint of different areas of science with the use of forward possibilities of technical process, are examined.Наведено причини зростаючого інтересу до процесів сушіння, а також деякі аспекти взаємодії промисловості й наукових університетських колективів у втіленні та застосуванні. Розглядаються тенденції дослідження процесів сушіння, що з'являються на стику різних галузей науки з використанням поступальних можливостей технічного процесу.
Simulation of nanoparticle aggregation processin heterogeneous dispersed systems
(2020) Olishevskyi, Valentyn; Vasylenko, Sergei; Babko, Evhen; Lementar, Sviatoslav
The stady of particle aggretion is relevant and stidied in chemical technology, biophysics, in solving problems of purification from aerosol or colloidal contaminants. The influence og nanoparticles on the aggregation kineticsds. The influence of nanoparticles on the aggregation kinetics of dispersed phases in suspension is considered. Models based on modifications of the particle dynamics method taking into account Van der Waals forces, gravity, Brownie and Stokes forces based on semi-empirical dependences for the rate of aggregation and disaggregation in collisions are used. Based on the analysis of the Smolukhovsky equation, molecular kinetic and localisotropic turbulence of Kolmogorov's theories, the dynamics of simultaneous turbulent and Brownian transfer to the process of "rapid coagulation" and the mechanism of influence of nanoparticles on their accumulative ability in colloidal heterogeneous dispersion are proposed. The developed equations for the rate of kinetic energy scattering in a suspension makes it possible to determine the particle dispersion in which the Brownian diffusion of particles in the coagulation mechanism predominates. This means, the more intense the process of mixing the suspension, the greater the role in the process of coagulation, precipitation and filtration play particles of the nanoscale range, which are included in the rapid movement of the vortex. These results are useful for practical application in control of intensity of coagulation processes in mixing devices. Conclusions. The mechanism of influence of nanoparticles on their aggregation ability in colloidal heterogeneous disperse systems is offered.
The formation of carcinogenic compounds in soluble powder of jerusalem artichoke
(Nauka i studia, 2013) Shutyuk, Vitaliy; Bessarab, Alexander; Vasylenko, Sergei
The extraordinary problem of production of quality foodstuffs is that they have various harmful substances, heavy metals and radionuclides. The most dangerous things for human health are cancerogenic substances which contained in negligible concentrations in foodstuffs and cause malignant formations in organism. One of the most dangerous carcinogen is N – nitrozodymetylamin wich is formed during formation amine groups under the influence of temperature. This paper presents the results of researches to determine the formation of N – nitrozodymetylamin during receiving powdered extract of Jerusalem artichoke.
The research of the amount of heavy metals and nitroso compounds in concеntrated tomato products
(2016) Shutyuk, Vitaliy; Vasylenko, Sergei; Bessarab, Alexander; Benderska (Dushchak), Olga
The constant selling race results in need for improving the quality of nutrition products among in-house food and pharmaceutical processing industries, which is an all-important key to success on the consumer market. This requires constant improvement of the product producing technologies. The topical problem of quality is the presence of heavy metals and nitroso compounds in the products. The topical problem of quality is the presence of heavy metals and nitroso compounds in the products. The research aimed at studying the changes in the heavy metal concentration levels (including Zn, Cu, Pb) in tomato products at their thickening has been conducted at the national University of Food Technologies.
Thermodynamic analysis of heat exchanging appliances
(2013) Shutyuk, Vitaliy; Samiilenko, Serhii; Vasylenko, Sergei
The article examines the methodology of thermodynamic analysis and the optimization of heaters and heat exchangers of heat engineering complex of saccharine industry. The authors suggest noncyclic approach to the analysis of efficiency of heat exchanging apparatus, the basis of which is irrefutable fact that irreversibility as physical reason of inefficiency of technical heat engineering systems really exists. Thermodynamic analysis, which was mentioned in the article, assumes determination of measure of irreversibility of processes in the apparatus and energetic efficiency of apparatus in the whole with the help of exceptionally entropy. The measures taken to improve energetic efficiency of apparatus of saccharine factory on the example of the first group of juice heating in front of evaporator system using the given methodology, were fully analyzed. В статті розглянуто методику термодинамічного аналізу та оптимізації підігрівників і теплообмінників теплотехнологічного комплексу цукрового виробництва. Авторами запропоновано нециклічний підхід аналізу ефективності теплообмінних апаратів, в основі якого – беззаперечний факт існування необоротності як фізичного джерела неефективності технічних теплотехнічних систем. Наведений в статті термодинамічний аналіз передбачає визначення міри необоротності процесів в апараті та енергетичної ефективності апарата в цілому, використовуючи виключно ентропію. Застосовуючи дану методику, комплексно проаналізовано заходи з підвищення енергетичної ефективності теплообмінних апаратів цукрового заводу на прикладі першої групи нагрівання соку перед випарною установкою.
Thermodynamic analysis of the thermal-technological complex of sugar production: the energy and entropy characteristics of an enterprise
(2020) Vasylenko, Sergei; Samiilenko, Serhii; Bondar, Vladimir; Bilyk, Olena; Mokretskyy, Vitaliy; Przybylski, Wlodzimierz
This paper reports the approbation of a procedure of thermodynamic analysis of the thermal-technological complex of sugar production using the analysis of an enterprise of typical configuration as an example. Currently, the thermodynamic analysis of sugar production systems is mainly performed on the basis of a classical energy method. Minor attempts to exploit the potential of the second law of thermodynamics in the form of the adaptation of an exergy method are not systemic. Underlying the applied procedure is a joint analysis of general synthetic and analytical balances of mass, energy, and entropy. Such a procedure makes it possible to quantify the level of perfection of the existing and proposed thermal circuits, as well as the impact exerted on their perfection by energy efficiency measures, and it could be applied both to optimize the energy characteristics of the existing ones and in designing new enterprises of the sugar industry. It has been shown that the thermodynamic analysis of the thermal-technological complex of sugar production as a single system makes it possible to analyze the main factors of influence on the energy efficiency of the complex disregarding the course of the processes implemented therein. Such an approach can also be effectively used for the quick evaluation of the thermodynamic perfection of an enterprise and for determining its «energy-saving potential». Based on the results of energy analysis, the relationship has been established between the fuel and energy resources, supplied to the system, and the sources of their losses; a set of measures has been proposed to reduce the impact of each of these factors on resource consumption. Entropy analysis has revealed the internal and external causes of the irreversibility of processes; the principle of «energy irreversibility compensation» has made it possible to compile a rating of major imperfections and determine the optimal sequence of resource-saving measures. The results of the analysis have confirmed the efficiency of the procedure, which allows a comprehensive study, while operating only with the fundamental laws and the principles of classical thermodynamics, as opposed to procedures, based on energy-exergy characteristics
Thermodynamic analysisof sugar production heattechnological complex:analysis method
(2020) Vasylenko, Sergei; Samiilenko, Serhii; Bondar, Vladimir; Bilyk, Olena
The object of research is the heat-technological systems of sugar production and the heat-technological complex as a whole. A modern sugar factory is a complex hierarchical system of inextricably interconnected elements, and its basis – a heat-technological complex – combines the elements of technological, heat transfer, and mechanical equipment, in which complex physicochemical processes are simultaneously realized, closely interacting. Given the complexity of the internal relationships of processes, their parameters and characteristics, it is necessary to systematically approach the analysis of real functioning, performance evaluation and the solution of optimization problems of the complex as a whole, as well as its individual subsystems and elements. In this work, it is proposed a method for thermodynamic analysis of the heat-technological complex of sugar production as a single thermodynamic system, which allows to analyze the main factors influencing the energy efficiency of the complex regardless of the course of processes implemented within the system. The methodology is based on a joint analysis of the general synthetic and analytical balances of mass, energy and entropy. This model has a deep physical foundation, because the material balance equation is an integral form of the law of conservation of the quantity of matter, the energy balance equation is an integral form of the first law of thermodynamics, and the entropy balance equation is an integral form of the second law of thermodynamics. The main objective of the methodology is a quick assessment of the excellence of the heat-technological complex and its definition of “energy-saving potential”. Also, the application of the principle of energy compensation of irreversibility and entropy criteria allows to determine the sources and causes of system imperfections, and imperfections are compiled to help develop a system of measures to increase the efficiency of the optimal sequence complex. Therefore, the proposed methodology of thermodynamic analysis, in contrast to the methods based on exergy characteristics, provides a comprehensive analysis, operating only with the fundamental laws and principles of classical thermodynamics. It can also be used both to optimize the energy characteristics of existing ones and to design new sugar industry enterprises
Ways of reducing nitrogen oxides in the drying agent to Improve beet pulp quality
(2014) Shutyuk, Vitaliy; Bessarab, Alexander; Vasylenko, Sergei
The article deals with the analysis of nitrogen oxides NOx formation in the agent for beet pulp during combustion process of various fuels. Various methods of reducing the nitrogen oxides concentration, formed in the fuel combustion conditions at high temperatures, are given. It is established that the output of nitrogen oxides during gas combustion is mainly determined by the maximum temperature of the combustion products and their rate of cooling. It is shown that the nitrogen oxides toxicity determines the overall level of toxicity of combustion products of coal and fuel oil on 40...60 % and 92…98 % of natural gas. Radical method to eliminate NOx is a noncontact method of preparation of the drying agent.