Irina G. Akhmetova

THE PURPOSE of the study was to propose a more effective option for heat conservation through the insulation of building envelopes. Calculations were analyzed using PHPP (Passive House Planning Package) software. Research and calculations revealed that insulating building envelopes can significantly reduce energy consumption for heating. The impact of these measures was analyzed on the fuel and energy balance of Mongolia. SIGNIFICANCE. The scientific significance of the study lies in its comprehensive assessment of the impact of insulating building envelopes on reducing heat loss, energy consumption, and CO2 emissions in Mongolia. METHODS. The study utilized analytical and computational methods. PHPP software, which allows for the modeling of energy performance of buildings with different insulation options and envelope thicknesses, was used to assess heat loss and potential energy savings. RESULTS. All existing older buildings belong to energy efficiency class D. To achieve energy efficiency, these buildings must be classified as energy efficient or class A, and all building envelopes must have insulation at least 250 mm thick and a thermal conductivity of 0.04 W/(m∙K). For panel apartment buildings, assuming windows insulated with energy-saving double-glazed windows, the annual consumption is calculated to be 133.8 GWh. The implementation of this measure could save 368.6 GWh of thermal energy and reduce 263.3 thousand tons of CO2, which is in line with the Paris Agreement targets for 2030. For brick apartment buildings, the annual consumption is calculated to be 99.1 GWh. Implementing this measure would save 305.3 GWh of thermal energy and reduce 218.2 thousand tons of CO2. CONCLUSION. Currently, the annual heat consumption of panel buildings is 502.1 GWh (431,700 Gcal), and that of brick buildings is 404.4 GWh (347,700 Gcal) in Ulaanbaatar. This figure accounts for 53 percent of the thermal energy in fuel and energy balance of Mongolia.

Thermal insulation materials used in power and industrial systems must maintain high performance under extreme environmental conditions. Among such materials, aerogel and basalt fiber are widely applied due to their low thermal conductivity and ease of installation. However, over time, these materials are susceptible to degradation, which can significantly impair their insulating efficiency and increase energy losses. Despite their importance, the long-term behavior of these materials under realistic climatic stressors has not been analyzed enough. This study investigates the degradation of thermal insulation performance in aerogel and basalt fiber materials subjected to complex atmospheric stressors, simulating long-term outdoor exposure. Aerogel and basalt fiber mats were tested under accelerated aging conditions using an artificial weather chamber equipped with xenon lamps to replicate full-spectrum solar radiation, high humidity, and elevated temperatures. The results show that the thermal conductivity of aerogel remained stable, indicating excellent durability under environmental stress. In contrast, basalt fiber insulation exhibited a deterioration in thermal performance, with a 9–11% increase in thermal conductivity, corresponding to reduced thermal resistance. Computational modeling using COMSOL Multiphysics confirmed that aerogel insulation outperforms basalt fiber, especially at temperatures exceeding 200 °C, offering better heat retention with thinner layers. These findings suggest aerogel-based materials are more suitable for long-term thermal insulation of high-temperature pipelines and industrial equipment.

Relevance of the study lies in solving environmental issues related to the discharge of wastewater at thermal power plants (TPPs) in Uzbekistan and Mongolia, which lead to the need to apply and improve methods for its purification.The purpose. To consider the problems of wastewater treatment at thermal power plants. To conduct a study of modern technologies for wastewater treatment for their application at thermal power plants in Uzbekistan and Mongolia. To consider the simplest, most economical and dischargeless technologies for wastewater treatment at energy facilities.Methods. In solving the problem, the method of calculating the volume of wastewater implemented by means of SMath® was adopted.Results. The article describes the relevance of the topic, considers the problems of wastewater treatment at thermal power plants. The volume of industrial wastewater, which after preliminary treatment can be used for the technological needs of thermal power plants, is calculated. This paper presents data on the tests of new generation sorption materials: aluminosilicate sorbent EcoFerox, activated carbon grade AK47 and APT-1 at a concentration of petroleum products СPP ≈ 20 mg/dm³ based on diesel fuel, transformer and turbine oils.Conclusion. A new scheme for cleaning and reusing wastewater for existing and planned thermal power plants in Uzbekistan and Mongolia has been developed. The proposed solution will partially solve the problems of water consumption at energy facilities in conditions of acute shortage of water resources. The obtained results showed that sorbents can be used for additional purification of wastewater from NP to the required MAC standards. It was established that the highest degree of purification of wastewater from NP is achieved when using filters with a two-layer load.

RELEVANCE. The relevance of this work lies in the creation of a certified software package (SEC), which is focused on solving problems of interest to the thermal power industry. One of the tasks chosen by the authors is devoted to improving the efficiency of the well-known gas turbine cycle by modernizing the thermal power circuit, which refers to a gas turbine plant (GTP). It should be noted that for CHP and GTP, the problem of increasing/improving energy criteria (Z1 - electrical efficiency, Z2-thermal efficiency, etc.) is a priority. The article considers in detail a number of objects, among them there are: a) the domestic mathematical package (MP) SMath, b) the package of functions (PF) WaterSteamPro, c) websites, d) the computer environment (CS) Linux. When creating the SEC, the authors solved issues those are relevant, firstly, for generating plants, including thermal power plants and combined cycle gas plants (CCGP); secondly, the authors considered the problems that play an important role in the modernization of the GTP, which includes a recovery boiler. Purposes. The authors consider several goals. The first is related to the development of method I, which should ensure the optimization of criteria characterizing the PGU-1 power plant under study. This technique is based, in particular, on Information Technology (IT); it uses a number of open interactive (OS) algorithms. These algorithms allow the researcher to conduct thermal energy (TE) calculations aimed at determining energy criteria, Z = (Z1, Z2, ...). Based on method I, the PROBLEM (A) is solved, which is related to the search for optimal parameters, Yopt= (Y1, Y2, ...), characterizing the thermodynamic cycle of PGU-1, here Y1 is the temperature at the inlet to the compressor, Y2 is the pressure at the inlet to the gas turbine. The second goal is related to the creation of a "Multifactor technology for the formation of OS algorithms." This technology makes it possible for a researcher who performs TE calculations to attract such tools that correspond to the world level of IT (SMath MP, Linux MP, Mathcad Calculation Server tool, etc.). In accordance with the second goal, a number of TASKS are being solved; among them is a task aimed at the SEC complex, as well as the task of creating an OS algorithm for TE calculations that are focused on PSU and MP Linux. Results. The article describes, firstly, the SEC complex. Secondly, the TE calculations were performed in accordance with the tasks set. So, in task (A), the PGU-1 is analyzed, which contains a number of blocks (a steam turbine; a part aimed at the internal heating of a vocational school, a heat recovery boiler, etc.). As a result, numerical data and graphical illustrations were obtained, including an assessment of the criterion Z2= 48.68% for the vocational training unit under Yopt conditions and a thermal power scheme for PGU-1 was selected. Conclusions. Currently, for well-known reasons, domestic researchers are switching from foreign software to domestic developments. An analysis of the results obtained in these TE calculations allows us to conclude: SMath MP and the SEC complex have enabled researchers to successfully abandon software that relies on Mathcad MP, Maple MP, Mathematica MP and MATLAB MP.

The reliability of heating networks is the foremost principle for organizing relationships in the field of heat supply, as established by Federal Law. The overall reliability of heat supply across the Russian Federation is declining due to insufficient replacement of aging heating networks. This article explores the potential use of a program document, specifically a heat supply scheme, as a means to justify the allocation of budgetary funds for initiatives aimed at enhancing the reliability of heat supply or transitioning to a “price zone.”.

THE PURPOSE. In modern realities, the operation of heat networks of the district heating system involves a constant search for ways to minimize heat energy losses. METHODS. Therefore, the task of minimizing heat energy losses while controlling the temperature of the supplied heat transfer medium from the sources of heat becomes very important. When operating district heating networks in the Russian Federation, regulation of heat supply to consumers during the heating period is carried out depending on the outside air temperature, as a rule, in two ways: qualitative method by changing the water temperature in the supply main of the heating network; qualitative-quantitative method by changing the temperature and water consumption in the supply main of the heating network. The methods of regulation used are related to the need to maintain a stable hydraulic mode of heat networks. Actions on the regulation of heat supply to consumers are performed at the heat source in accordance with the indication of the heat network dispatcher according to the approved temperature schedule for the heat supply system. RESULTS. This paper presents the results of a study of the dependence of changes in the actual heat losses for the section of the heating network, which is during the operation process in a non-stationary mode. Criteria for setting the temperature of the heat carrier at the heat source required to meet the temperature schedule by the heat network dispatcher are proposed. The results obtained can also be used in organizations operating district heating networks to ensure the regulation of the heating network operation mode with minimum heat losses. CONCLUSION. The nature of changing the temperature of the supplied coolant in the network (the interval of setting a new value and the rate of temperature change) directly affects the heat energy losses in the surrounding pipeline environment, resulting from the temperature gradient of the coolant in the pipeline and the environment. Given the fact that the values of the temperature of the outside air, heat-carrier, affecting the operating mode of the heating system is constantly changing over time, the processes of heat-exchange (heat transfer) between the coolant and the environment surrounding the pipeline are unsteady. The work reviewed the current requirements of regulatory and technical documents on the setting of the heating network operation mode, analyzed the factors affecting changes in the mode of the heating system.

The paper presents the results of studies of the influence of the degree of humification of peat on the mechanical and thermal insulation properties of composite thermal insulation materials. Peat samples were taken from a deposit in Totemsky district of the Vologda region from depths of 0.5 and 2 m. Highland peat (from a depth of 0.5 m) has a low degree of decomposition - 14...16 %, lowland peat (from a depth of 2 m) has a degree of decomposition of 39 %. The physicochemical analysis of the studied peat samples was carried out. The chemical composition of the water extract and the characteristics of peat are determined by gravimetric, titrimetric, ionometric, photoelectrocolorimetric methods of analysis. The results of the analysis showed that, depending on the depth, peat has the following characteristics: the moisture content of highland peat is 41.8...42.1 %, lowland peat - 54.21...54.23 %; the content of organic substances in the highland peat is 81.72...81.75%, in the lowland peat - 88.18...88.21%; the ash content of highland peat is 18.25...18.28%, lowland peat - 11.79...11.82%. Based on peat samples, heat-insulating mixture samples were created containing: 30...50% highland peat, 25...45% lowland peat, acting as a natural heat insulator and binder; 5% undecomposed plant residues acting as a binder; 10% peat extract containing resinous and sugary fractions and 10% organosilicon polymer (OSP) brand KS-12 to increase the strength characteristics. After cooling the finished composite heat-insulating mixtures, their characteristics were studied, namely: average density (Fig. a), thermal conductivity coefficient (Fig. b), compressive strength (Fig. c) and ignition temperature (Fig. d). The research results showed that an increase in the proportion of highland peat (with a low degree of decomposition) in the mixture leads to a decrease in the average density from 238 to 229 kg/m3, a decrease in the thermal conductivity coefficient from 0.048 to 0.042 W/mK, a decrease in the compressive strength from 1.47 mPa to 1.17 mPa and a decrease in the ignition temperature from 748 to 690 °C.

This paper presents the results of theoretical and experimental studies to determine the optimal thickness of thermal insulation from basalt fiber and aerogel products for pipelines at temperatures of 300 and 600 °C. We carried out a comparison of the key thermophysical characteristics of the claimed heat-insulating materials. We performed a thermal imaging survey of the furnace chimney, insulated with basalt fiber and aerogel, while controlling the temperature of the flue gases by establishing the required ratio of the flow rate of natural gas and oxidizer. The temperature gradient along the thickness of the thermal insulation was obtained using a numerical tool developed in ANSYS. The results show that aerogel surpasses basalt fiber in all key thermophysical characteristics. At the same time, the only barrier to widespread industrial production and use of aerogel in the high-temperature thermal insulation segment is its market cost, which is still several times higher than that of basalt fiber in terms of an equivalent performance.

Currently, in the context of the transition to the development of new sources of renewable energy, the issues of digitalization of the energy sector are becoming increasingly relevant. Digitalization captures all areas of activity and involves the integration and transformation of the energy system, which makes it possible to obtain socio-economic effects. Five groups of indicators have been identified (human capital, reliability and quality of power supply, availability of electricity, environmental sustainability, and political and infrastructural readiness of the country for digitalization), which provide an objective assessment of the digitalization indices of the energy sector of a particular country. Approbation of the procedures and the results obtained was carried out by the method of factor analysis using limited and contributing functions. As a result of the assessment, the leading countries were identified in terms of the digitalization of the energy sector, which have an impact on countries with a low level of digitalization and on the development of mechanisms and tools for the digitalization of the sector. As part of this study, the prerequisites and main components of the readiness of countries for the digitalization of the energy sector are highlighted. The applied analytics made it possible to identify potential points of growth in the digitalization of countries with its low level, to develop appropriate measures. Seven stages of the processes of digitalization of the Russian energy sector are identified, indicating the resulting effects and directions for its possible development.