Кафедра екології, теплотехніки та охорони праці (ДМетІ)

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ENG: The department of Ecology, Heat-Transfer and labour protection (DMetI)

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Determination of Operating Parameters of Accumulative Electric Heating Systems
(IOP Publishing Ltd, 2024) Kolienko, Anatoliy G.; Ahmednabiev, R. M.; Gupalo, Olena V.; Demchenko, O. V.; Hukasian, O. M.
ENG: The article presents the results of research aimed at determining the parameters and characteristics of storage heating systems, justifying the possibility of using heat accumulators to increase the efficient use of energy that is generated, including from renewable sources. The virtuality, frequency and significant dependence on natural conditions and climate of renewable energy sources, as well as the need to optimize their installed capacity, leads to the need to use energy storage installations. The presence of efficient energy batteries is a prerequisite for modern efficient energy and heat supply systems. The methodology of the work is based on our own theoretical and experimental studies, which provide practical recommendations for the arrangement of energy accumulators obtained using renewable heat sources. This is especially relevant for Ukraine during the period of active military operations on its territory, the destruction of traditional energy sources and a shortage of generating capacity. Recommendations have been developed for the design of heat accumulators for heating systems of residential and public buildings. Their effectiveness has been assessed under conditions of limited use of fossil fuels and the use of hybrid energy sources. Scientific and practical results of the work make it possible to carry out low-cost reconstruction of heating systems for the introduction of storage systems using electrical energy, the source of which is wind and solar energy. Such developments are becoming particularly relevant in Ukraine, taking into account the requirements for ensuring the stability and efficiency of infrastructure facilities in war conditions.
Improving the Technology of Using Freon-Steam Turbines in Mine Power Complexes
(IOP Publishing, 2022) Kirsanov, Mykhailo; Slobodiannykova, Inna; Gupalo, Olena V.
ENG: Mining power complexes can significantly reduce the cost of production of mining enterprises and increase their competitive position in the relevant market. To solve the urgent problem of further improving the operation of mine energy complexes, it is proposed to include in their composition installations for the useful use of energy from low-potential sources with a freon-steam turbine, which implement the thermodynamic Rankine cycle. The article considers the features of the organization of the Rankine cycle depending on the properties of freons. When choosing freons, the emphasis is placed on the use of strictly ozone-safe freons that meet modern requirements for normalizing the value of the global warming potential. The previously proposed method for calculating the thermodynamic parameters necessary for evaluating useful action’s coefficient of using specific freons in a useful energy recovery equipment has been improved. The calculation of the energy efficiency of the equipment with a freon-steam turbine for the selected options for the use of freons is performed. The analysis of the obtained results showed that the use of ozone-safe freons with low values of the global warming potential in installations for the utilization of energy from low-potential sources will improve the operation of mine energy complexes.
The Influence of Initial Parameters on the Process of Synthesis Gases Cooling during Plasma-Chemical Processing of Carbon-Hydrogen Containing Raw Materials
(IOP Publishing Ltd, 2025) Radchenko, Yurii M.; Shevchenko, Volodymyr; Oparin, Serhii; Gupalo, Olena V.; Davydov, Serhii
ENG: The paper investigates the influence of the productivity of plasma-chemical processing of carbon-hydrogen containing raw material and initial parameters of syngas on the performance of syngas cooler. The syngas cooler consists of a sequentially located radiation section, a preliminary convective section, a steam superheater, a main convective section, an economizer, and an autonomous water cooler. To determine the operating parameters of the syngas cooler, a well-known methodology based on the solution of heat transfer and heat balance equations was used. The main performance indicators of the basic cooler design (steam capacity, superheated steam temperature, heat utilization coefficient of syngas) were determined for the ranges of 100 - 400 m3/h and initial temperature of syngas 2000 °C. The research results were summarized in the form of analytical dependence of the total area of heat-exchange surface of the cooler on the flow rate of syngas in the range from 100 to 400 m3/h, which can be used in optimization of equipment for plasma-chemical technology of hydrogen production at minimum of total costs.
Method of Sequential Approximation in Modelling the Processes of Heat Transfer and Gas Dynamics in Combustion Equipment
(MDPI, Switzerland, 2022) Rimar, Miroslav; Yeromin, Oleksandr O.; Larionov, Grigoriy; Kulikov, Andrii; Fedak, Marcel; Krenicky, Tibor; Gupalo, Olena V.; Myanovskaya, Yana V.
ENG: The behavior of the processes taking place in furnaces determines the efficiency of fuel chemical energy utilization, the quality of the final products and the environmental safety of the production. Mathematical models of the processes of gas dynamics and heat transfer in the working space of heating equipment are quite complex, and do not allow the establishment of a direct analytical relationship between the quality indicator of the process (F) and the influencing parameters (xi). To simplify the procedure for obtaining the values of the function F depending on the change of parameters xi, a method of successive approximation is presented in the article. The main idea of the method is that the representation of the function around a point from the domain of the function can be extended to the entire domain for many problems of mechanics. The relative error in the definition of the function acquires its maximum value at the border of the area, and a reasonable narrowing of it allows control of the size of the error. Thus, the advantages of using the method are obvious; it is able to provide approximation of the function in a multiplicative form with a controlled error. The distribution of the method to the field of heat transfer problems is presented in this paper. The successful implementation of this method for solving problems of this kind shows that the solution of practical problems may be generalized for the entire domain of the function, despite the fact that the errors of such a representation increase to 5–7% when approaching its limit, which, however, may be considered acceptable for engineering calculations.
Modeling of Thermophysical Properties of Carbon Dioxide in the Range of Turbine Operating Parameters Based Low-Potential Thermal Resources
(IOP Publishing Ltd, 2026) Kirsanov, Mykhailo; Gupalo, Olena V.
ENG: The efficient use of secondary and natural energy resources to generate additional electricity is an important factor in improving the economic performance of industrial sectors. In the mining industry, considerable volumes of secondary and renewable heat resources with temperatures between 27 and 75ºC are available. Their effective utilization is possible through gas turbine systems operating with carbon dioxide as the working fluid. Although thermodynamic tables for carbon dioxide exist, they are difficult to apply in analytical studies involving variable parameters. Simplified analytical equations have been developed for carbon dioxide thermodynamic properties at several isobars within typical gas turbine pressure ranges. However, to determine and analyze optimal gas turbine operating modes when using low-potential heat resources from mining enterprises, it is necessary to have analytical expressions covering the entire temperature and pressure range relevant to turbine operation. Developing such equations was the main objective of this work. The study also demonstrates their practical application using specific thermal source parameters.
New Working Fluids for the Use of Heat Secondary Sources in Mining Technologies
(IOP Publishing, 2023) Kirsanov, Mykhailo; Gupalo, Olena V.; Podoliak, Kostiantyn
ENG: Production cost of mining enterprises can be significantly reduced when using secondary heat. A large volume of secondary heat sources has a temperature potential of no higher than 50ºС. To generate additional electricity using secondary heat it has been proposed to use installations with the Rankine thermodynamic cycle in mining enterprises. The paper aim is to study the thermodynamic efficiency of using R-1234yf and R-744 in the equipment, which uses the secondary heat of mining technologies for evaporation of these working fluids. R-1234yf is a freon that belongs to the class of hydrofluoroolefins and has a much lower level of global warming potential than other ozone-depleting substances. R-744 is carbon dioxide, which belongs to a natural, non-toxic and non-flammable working substance. It has been determined that the thermodynamic efficiencies of using R-1234yf and R-744 are 10% and 6.3%, respectively. The thermodynamic efficiency has been calculated for the temperature range from 50º to 20ºC, which is typical for a large volume of secondary heat sources in mining technologies.
Prediction of Fuel Consumption and Carbon Dioxide Emission when Replacing Gaseous Fuels with Renewable Hydrogen or Their Mixture
(IOP Publishing Ltd, 2024) Gupalo, Olena V.; Yeromin, Oleksandr O.; Kabakova, Liudmyla; Kolienko, Anatoliy; Kirsanov, Mykhailo; Kulikov, Andrii
ENG: The paper is devoted to predicting changes in fuel consumption and carbon dioxide emissions when industrial equipment is converted to heating with renewable hydrogen or a mixture of it with other gaseous fuels, such as natural gas. The authors developed a simplified methodology that is appropriate for assessing changes in the energy consumption of equipment and the environmental impact of fuel replacement at the stage preceding the equipment reconstruction. The peculiarity of the methodology is that it allows the calculation of fuel consumption and carbon dioxide emissions when fuel replacement is accompanied by the implementation of measures aimed at improving the energy efficiency of equipment. The methodology can be used for heating and thermal furnaces in metallurgy and mechanical engineering, units for heat treatment of raw materials in the mining and processing industries, heating devices in the food industry, and water and steam boilers. In the example of replacing natural gas with its mixture with renewable hydrogen of different compositions, it is shown that the calculation error using the proposed methodology in comparison with the results obtained by mathematical modeling of fuel combustion, gas flow and heat transfer in this furnace does not exceed 1.5%.
Research on the Efficiency of Hydrogen Combustion, Alternative and Natural Non-Interchangeable Gases
(The Gas Institute of the National Academy of Sciences of Ukraine, Kyiv, 2025) Kolienko, Anatoliy G.; Sigal, O. I.; Gupalo, Olena V.; Akhmednabiev, Rasul M.
ENG: The results of determining the gas interchangeability criterion are presented. An analysis of the possibility of adapting existing gas combustion plants for the effective and stable use of a wide range of combustible gases is performed. It is shown that even natural gases from different deposits are not always interchangeable. Recommendations are developed that allow the use of even non-interchangeable gases on the same gas combustion equipment by changing the operating settings or slightly changing the design characteristics of the equipment. The results of the study of heat transfer in the combustion space when the composition of combustible gases changes and the associated changes in the emissivity of combustion products are presented. Recommendations are given on the organization of the combustion process of non-interchangeable gases, including by creating mixtures of combustible gases with the provision of the necessary interchangeability criteria. The purpose of the work is to study the possibility of effective combustion of alternative types of artificial and synthetic combustible gases, including hydrogen, as well as non-interchangeable natural gases in existing gas combustion equipment. Study of the properties of combustible gases characteristic of gas distribution systems of Ukraine, and their compliance with the inter-changeability criteria and gas combustion equipment manufactured and supplied for industrial and municipal purposes. The relevance of the issues of ensuring the interchangeability of gases is confirmed by the implementation of regulatory legal acts on the quality indicators of combustible gases and the efficiency of their use in the national legislation of Ukraine. The results of the study provide the possibility of a barrier-free gradual introduction of alternative types of gases and a gradual transition to the combustion of gases with hydrogen content without cardinal changes in the design of existing burners and their operating modes. Bibl. 26, Fig. 2, Tab. 5.
Rheological Properties of Polymer-Polymer Mixtures on Corn Starch Base
(MM Publishing s.r.o., Praha, Czechia, 2022) Rimar, Miroslav; Tretyakoff, Artem; Sukhyy, Kostyantyn M.; Yeromin, Oleksandr O.; Kulikov, Andrii; Fedak, Marcel; Belyanovskaya, Elena; Shunkin, Ihnat; Gupalo, Olena V.; Krenicky, Tibor
ENG: The prospects for the use of polymer-polymer mixtures based on corn starch as alternative thermoplastic materials to polyolefins are considered. Rheological curves have been obtained, which confirm the possibility of processing such mixtures on standard equipment into products. It is shown that the starch content in polymer-polymer mixtures can reach 90 mass percent. Compared to existing biodegradable polymers, plasticized starch-based material is in no way inferior to them in terms of processability. Studies of the mechanical properties of polymer-polymer mixtures based on corn starch have been carried out. The data obtained indicate the possibility of using the developed composites as packaging materials, as well as alternative materials to known bioplastics and synthetic polymers.
Study of the Efficiency of a Gas Turbine on CO2 for the Use of Secondary Heat of Mining Enterprises
(IOP Publishing Ltd, 2025) Kirsanov, Mykhailo; Slobodiannykova, Inna; Gupalo, Olena V.; Privalov, Vladimir
ENG: The mining industry has significant sources of secondary thermal resources with low temperatures of 35°C- 80°C. For their use in the production of additional electricity, it is proposed to use a gas turbine that operates on carbon dioxide (freon R-744) and implements the Rankine cycle. Known detailed tables and model equations for carbon dioxide describe its thermophysical properties. However, they are very complex and challenging to access for inspection. Therefore, this article aims to develop simple analytical expressions for the thermophysical parameters of R-744 for temperatures of 3°C- 80ºC and use them to study effective operation modes of a gas turbine for the use of secondary heat resources of mining enterprises. Mathematical modelling methods, theories of approximation of functions, fundamental laws of gas dynamics and technical thermodynamics were used to achieve the goal. The study resolved the issue of selecting an effective turbine operating mode based on the level of thermodynamic efficiency based on general thermodynamic laws. It was shown that reducing the cooling temperature of R-744 in the condenser from 20°C to 5°C due to the use of mine water increases the thermodynamic efficiency of the Rankine cycle almost twice.
Study of the Efficiency of Using Renewable Hydrogen in Heating Equipment to Reduce Carbon Dioxide Emissions
(IOP Publishing, 2023) Gupalo, Olena V.; Yeromin, Oleksandr O.; Kabakova, Liudmyla; Kulikov, Andrii; Sukhyi, Mykhailo; Romanko, Yaroslav V.
ENG: The results of theoretical study of operation of continuous furnaces heated by natural gas, renewable hydrogen, and their mixture are presented. The furnaces have the same design, but significantly different energy efficiencies due to different heat losses and capability of recuperative fume gas heat utilization system. The measures to reduce heat losses and to increase air temperature for fuel combustion can reduce specific fuel consumption for metal heating and carbon dioxide emissions by 25.8% for natural gas furnaces. For furnaces operating on mixture of natural gas and hydrogen, a greater reduction in carbon dioxide emissions is achieved in furnaces with worse energy efficiency, but with greater fuel consumption for metal heating. The paper shows the possibility of converting a furnace with better energy efficiency indicators to be heated by mixture of natural gas (75%) and hydrogen (25%). The measure reduces the natural gas consumption and carbon dioxide emissions to 9.2% due to the use of hydrogen with specific consumption 13.81 m3 per ton of metal. To ensure the same costs for metal heating when transferring continuous furnaces from natural gas to hydrogen, or their mixture, the ratio of prices for natural gas and hydrogen should not exceed 0.301-0.312.
Synergy of Secondary Energy Resource Utilization and Hydrogen Technology for Reducing the Carbon Footprint of Industrial Thermal Units
(IOP Publishing Ltd, 2026) Kolienko, Anatoliy G.; Gupalo, Olena V.; Akhmednabiev, Rasul M.
ENG: The article presents research results focused on improving energy efficiency and reducing the carbon footprint during pellet burning in rotary kilns. The study includes experimental kiln production, development of its energy balance, analysis of energy loss components, assessment of renewable and non-renewable energy losses, and determination of greenhouse gas emissions. The influence of operating parameters on kiln efficiency was examined, and their optimal values were identified. The thermal potential of secondary energy resources at the pellet burning plant was evaluated. A waste-heat utilization scheme for municipal and domestic heating and hot water supply was proposed. The study also establishes dependencies demonstrating the potential for reducing CO2 emissions when substituting natural gas with a mixture containing reducing hydrogen. Research results on lowering the carbon footprint by burning environmentally neutral biomass are presented, along with practical recommendations. The scientific and applied outcomes of the work enable the development of measures aimed at decarbonization and enhancing the efficiency of rotary kilns used for pellet burning in mining and metallurgical enterprises.
Technological Aspects of Purification and Separation of Hydrogen-Containing Gases Obtained by Gasification of Solid Carbon-Containing Media
(M.S. Poliakov Institute of Geotechnical Mechanics of the National Academy of Sciences of Ukraine, Dnipro, 2025) Shevchenko, Volodymyr; Oparin, Serhii; Davydov, Serhii; Gupalo, Olena V.
ENG: Іn this paper, the subject of study is the processes of purification and separation of hydrogen-containing gases obtained by plasma-chemical gasification of solid carbon-containing media. The work aims to establish the regularities of the influence of technological parameters of hydrogen-containing gases obtained by the gasification of solid carbon-containing media on the specific surfaces of filter partitions, membranes, and adsorbents used for their purification and separation. The graph-analytical research method is used in this work, which consists in finding rational specific surfaces of the processes of purification and separation of hydrogen-containing gases based on the obtained graphical dependencies. Analytical dependencies for calculating the specific surface areas of the filter partition, the membrane, and the adsorbent were established. These dependencies take into account the technological parameters of hydrogen-containing gases and the technological parameters of their separation to produce high-purity hydrogen. Based on the theoretical calculation results, a graphical dependence of the specific surface area of the filter partition on the temperature of hydrogen-containing gases formed during the gasification of solid carbon-containing media and the concentration of solid particles in the gas was obtained. This dependence shows that an increase in the concentration of solid particles and an increase in the temperature of hydrogen-containing gases lead to an increase in the specific surface area of the filter partition. The graphical dependence of the specific surface area of the polyimide membrane on the operating pressure and hydrogen concentration in the permeate and the graphical dependence of the specific surface area of zeolite 13X on the initial hydrogen concentration in the initial gas mixture from 60% to 90% at a final concentration of 99.99% are presented. The paper presents a schematic diagram of purification and separation of hydrogen-containing gases to produce high-purity hydrogen. According to the diagram, the hydrogen-containing gas obtained by the gasification of carbon-containing media is sent for purification from solid particles to a filtration system, from where it is supplied to membrane separation for concentration, and the concentrated hydrogen-containing gas is sent to adsorption separation, where it is separated to produce high-purity hydrogen.
The Use of Secondary Heat Resources during the Accumulation of Compressed Air in Closed Mining Workings
(IOP Publishing Ltd, 2024) Kirsanov, Mykhailo; Slobodiannykova, Inna; Gupalo, Olena V.; Podoliak, Kostiantyn
ENG: The article considers the possibility of energy accumulation in mining workings in order to reduce the consumption of fossil organic fuel by the mining enterprise itself. For this purpose, the authors propose to accumulate compressed air in closed mine workings using secondary heat resources to generate additional electricity. The energy management of mining enterprises can be equipped with freon steam turbines which implement the Rankine thermodynamic cycle to obtain additional electricity from secondary heat. To measure the efficiency of the process, the air mast be compressed isothermally. The compression must be carried out in several stages, and the air must be cooled after each stage. Taking into account the development of energy storage technologies in the form of compressed air in specially prepared closed mining workings, the required air pressure can be from 70 to 90 at. The article assesses the possibility of using a secondary heat resource during air compression at mining enterprises. It is shown that the use of freon steam turbines during the accumulation of compressed air in underground pressure accumulators increases the subsequent production of electricity during the operation of the air turbine by 7.6% during the day.