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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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.
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%.
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.
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.