A large number of NPP power units designed and built on the territory of Russia and Ukraine have exceeded or are close to exceeding the design operating life, even taking into account their extension. The terms of the extension of operation also have their limits, especially taking into account the types of reactors of the plants being extended. The complete dismantling of old nuclear power plants is an extremely costly undertaking. The article formulates the problem setting for converting double-circuit NPPs into thermal power plants with the possible use of the infrastructure and equipment of the turbine hall. The existing experience of NPP decommissioning is analyzed. Variants of application of boiler equipment, reconstruction of existing turbines and use of gas turbine plants for the implementation of options with a steam-gas cycle are considered. A comparison has been made of various options for completing fossil-fueled power units, their expected power, parameters and efficiency. Qualitatively, additional capital investments in new equipment, environmental impact and cost-effectiveness of the considered options for completing new TPP power units have been assessed. It is noted that the implementation of any of the considered options should be preceded by analysis of the condition of thermal mechanical equipment remaining in operation and a feasibility study of the proposed conversion option.

In accordance with the Energy Strategy of Russia until 2035 and the Decree of the Government of the Russian Federation "Improving the reliability and quality of power supply to consumers of electric energy through the introduction of new technologies and optimization of the activities of territorial grid organizations", the issues of improving the reliability of power supply of electrical complexes of industrial enterprises in a market economy are of particular importance.

This article presents the results of a survey of managers and specialists of the services of the chief power engineer of industrial enterprises, representatives of design institutes, equipment manufacturers, university researchers on the existing problems of reliability of power supply systems of industrial enterprises. The expediency of substantiating the identification of the current situation by the main reliability indicators and their relationship in the existing economic conditions for calculating the reliability of power supply systems is substantiated. A comparative analysis of the responses of respondents of energy services is presented, their interpretation is given.

The main problems in the following blocks are identified: the quality of the enterprise's energy supply and its reliability; the reliability of energy distribution within the enterprise and control of the influence of installed electrical equipment on the quality of the electrical network; knowledge regarding reliability and interest in carrying out such calculations. Recommendations are given on the identified problems, including the analysis of individual indicators of reliability of power supply to industrial enterprises.

Before being supplied to the transportation pipeline, natural gas must be cleaned from various impurities, with the specified parameters at the inlet to the transportation system — such as composition, mass or volumetric flow rate, pressure, and temperature — to be ensured. To this effect, a gas preparation system is designed, which includes various heat exchange units, cleaning and separation devices, as well as a turboexpander unit (TEU) consisting of a turbine and a coupled compressor.

During the operation of this system, the gas parameters are constantly changing due to variations in external and operating conditions, such as the parameters of the ambient air, the gas pressure and flow rate at the wellhead, the composition and the amount of impurities.

The gas preparation system therefore almost never operates in the designed conditions, which means that its proper operation requires the knowledge of its characteristics, i.e., the dependencies of the system parameters on external and operational conditions. Besides, the knowledge of the characteristics enables to control the system by affecting its various parameters.

The characteristics of the gas preparation system are determined by the characteristics of all of its elements, including the characteristics of the TEU as one of its most important elements.

The characteristics of the TEU enable to assess the impact of external conditions on its operating conditions and thus optimize the system's operation during its design stage. They also allow the determination of the parameters for regulating the TEU conditions.

A methodology for calculating the TEU characteristics is proposed, an example of the calculation is provided, and analysis of the obtained results is presented.

The article presents the results of the calculation of the energy consumption of the main and auxiliary technologies for the production of mineral fertilizers, interrelated as a single energy technology system (ETS). At the stage of the primary analysis of fuel, electricity and heat consumption indicators of individual technologies of the mineral fertilizers industry, the task was set to determine the energy intensity of specific technologies depending on intra-system distribution of flows of fuel and energy resources (FER) between the ETS production facilities for the output of target products.

On the basis of a mathematical model, according to the averaged specific consumption rates of fuel and energy resources of the main and auxiliary technologies for the production of one ton of product, the values of specific energy consumption for target technologies for the production of mineral fertilizers were obtained. The analysis of the calculated indicators of energy consumption enabled to identify the most energy-intensive technologies.. It is shown that in the total energy consumption of the target technology, the share of energy consumption of auxiliary industries is up to 97% of the total energy intensity. Besides, the paper cosiders the key factors that determine the level of energy efficiency of industry enterprises under study.

Through the example of an existing technology for the production of mineral fertilizers of one technological line with a capacity of 27.5 t/h (in terms of the finished product), the calculation of energy consumption was performed. The paper states that the modernization of the technology for the production of mineral fertilizers through the utilization of thermal SERs emitted into the environment would reduce the energy consumption of the technology by 6.33%.

The mathematical model used in the study makes it possible to determine the values of energy consumption of technologies in the mineral fertilizer production industry with the greatest accuracy. The analysis of the data obtained shows that the studied technologies of the industry are characterized by irrational consumption of fuel and energy resources and, therefore, need a more thorough and systematic approach in determining energy saving reserves and ways to rationalize them in the energy technology system (ETS).

Reduction of pollutant emissions into the atmosphere is an urgent task of modern gas turbine engineering development. Such substances that have a negative impact on the environment include nitrogen oxides and carbon monoxide. The article provides a review of the existing methods for reducing the emissions of pollutants used in the combustion of hydrocarbon fuels in the combustion chambers of gas turbine units, as well as indicates promising technologies developed based on these methods. Justification is presented of the necessity to study the method of ozonization of air supplied to the fuel combustion zone to reduce the content of pollutants in its combustion products. The purpose of the study was to develop recommendations for reducing pollutant emissions within a given range of variations regime parameters. To perform the necessary set of experimental studies, a specialized laboratory stand was created, the combined circuit and measurement scheme of which is given in the article. A rather detailed description is given of the structural elements of the stand and, in particular, of the subject of research — a full-scale vortex ignitionstabilizing module of the combustion chamber of a gas turbine unit, an electric ozonator, air and combustible gas supply systems, an exhaust system with a central fan, control and measuring instruments and fittings. The tests were carried out in accordance with specially developed methods of controlling the stand operation in three modes: startup; transfer from one steady-state mode to another; stop. The influence of air ozonization on combustion processes in the vortex ignition-stabilizing module was determined by the content of nitrogen oxides and carbon monoxide in it. The factors that influence the decrease in the concentration of carbon monoxide in the combustion products during the combustion of air in ozonized air have been determined. The methods of calculation determination of combustible gas and air parameters — mass flow rates, flow velocities and dynamic heads — are described. The results of the performed experimental studies are presented in graphical interpretation, their detailed analysis is given, on the basis of which recommendations on practical use of the method of air ozonization are given.

Throttling devices are used in hydraulic systems both as regulating valves and to provide protective functions, which determines the relevance of developing such a design that will ensure their cavitation-free operation. The aim of the study is to investigate cavitation phenomena in single-stage throttling devices with different geometry of the jet orifices in order to identify the geometric shape capable of minimizing cavitation. The paper presents a study of the effect of different geometric shapes of the orifices of single-stage throttling devices on cavitation formation in the low-pressure areas. In addition, the objective of the study is to investigate the influence of physical quantities (velocity and pressure) on cavitation formation and to carry out a comparative analysis by means of which the influence of the correlation between the geometrical shape of the orifice of the jets, the velocity of the working medium and the pressure in the area of the orifice of the jets on the formation of cavitation zones in the areas of reduced pressure is clearly demonstrated. The computational experiment was conducted using Ansys CFX software and was based on the Rayleigh-Plesset mathematical model of cavitation. The study investigated the possibility of cavitation phenomena in single-stage throttling devices, and identified the geometric shape of the jet orifice that promotes cavitation-free operation of the single-stage throttling device. Thus, the results of the study show that the jet with a conical orifice minimizes the volume fraction of vapor, arising during cavitation processes, in single-stage throttling devices. The conducted research has practical significance and can increase the service life of single-stage throttling devices by minimizing the formation of cavitation zones in areas of low pressure.

The possibility of using biomimetic approaches, in particular, the "lotus leaf" effect, expressed in the superhydrophobicity of streamlined surfaces, is considered. The results are presented of experimental studies of the influence produced by various modifications of the surface of the “plate” type canonical region on its hydraulic characteristics. The plates were streamlined in a hydrodynamic tray of rectangular cross-section. Copper plates with dimensions of 200x300x1 mm were studied. Three plates were considered, identical in geometry, but with different surface conditions — one in its original state; one with surfaces modified based on a surfactant; and one with surfaces treated by laser ablation (laser formation of a multimodal relief) with subsequent modification based on surfactants. In the course of experimental studies, the velocity distribution behind streamlined plates with different surface characteristics was obtained. Based on the nature of the velocity variations of the trail behind the streamlined plates, it is concluded that the amount of hydraulic resistance decreases due to surface modification. The weighted average velocity behind the streamlined plate increased by more than 4% for a plate with a combined modified surface compared to the original one. The process of a copper plate surface modifying using laser ablation, as well as the formation of additional surfactant molecular layers in order to achieve the maximum effect of superhydrophobicity is described. The most effective technological features of the laser ablation process are determined, such as the radiation power and frequency, the most preferred relief of modified surfaces and its geometric parameters. The most characteristic features of the influence of the surface roughness on the wetting angle (θ) are considered. With the OSA 20 complex, the wetting angles were determined for all the prepared plate samples. The research results prove the prospects of this surface modification technology for use in hydraulic machines.

A transportable boiler plant is used to provide consumers with steam of high energy characteristics, while saving costs for the construction of stationary boiler houses. A transportable boiler plant can be placed in the conditions of the Far North on an oilfield site. It is therefore necessary to organize reliable and safe operation of the boiler house, consisting of a steam direct-flow boiler of the coil type, a feed pump, a feed water tank and other auxiliary elements of the thermal circuit. One of the important elements in the thermal circuit is the feed water tank, in which water accumulates after chemical purification. It is where the water is also heated, increasing the efficiency of the boiler. Methods for calculating the diameters of main steam pipelines and feed water pipelines are described. The theoretical foundations of the operation of the feed water tank, its use in thermal power plants, combined heat and power plants, district industrial and heating boilers using various thermal arrangements of the above-mentioned enterprises are considered. The operation of the feed water tank in the thermal circuit of a steam unit is discussed. A thermal circuit of an industrial boiler house has been designed to generate saturated steam for consumers using direct-flow steam boilers of the coil type. The diameters of the inlet and outlet pipelines of the storage tank are calculated. The effective thickness of thermal insulation required to minimize heat losses during operation of a transportable boiler plant has been determined. Modeling of the design of the feed water tank and heat losses through its surface is carried out. A 3D model of the designed tank is presented, as well as heat losses through the surface of the tank walls when using a thermal insulation material. The importance of using thermal insulation of various tanks for storing feed water, petroleum products, hydrocarbons and other various media is noted.

This study is based on the analysis of the methodology for calculating the temperature parameters of 10 kV cable lines and calculating the service life of insulation under various operating conditions, as well as identifying dependencies that allow the most accurate selection of cable parameters during operation at industrial facilities. The results of the study can be used to improve the energy efficiency of enterprises, and contribute to reducing the number of emergency failures of cable lines that may occur due to thermal breakdowns caused by incorrect choice of cable parameters under certain operating conditions, which may cause an increase in production costs in general. Conducting research and calculations of temperature parameters of cable lines at a voltage of 10 kV with different laying methods and with different capacity factors according to the climatology of the Republic of Tatarstan, as well as identifying key dependencies that will enable to draw appropriate conclusions on the operation of cables in the conditions under consideration. The article uses methods for calculating temperature parameters and cable service life, as well as methods for processing the data obtained as a result of calculations, including the method of function approximation. Special software is also used to visualize the results obtained after the calculations. The results of calculations of temperature parameters of 10 kV cable lines for various laying methods, with different types of insulation and with different capacity factors according to climatology of the Republic of Tatarstan are presented. Calculations of the service life of cable lines under the conditions under study have been made and conclusions have been drawn on optimal cable loads that will not lead to premature thermal aging of insulation under certain operating conditions. The initial data for the calculations and the methodology used comply with GOST standards for cable lines. The results of the study and the calculations performed can be used to evaluate and select the optimal load of cable lines under selected conditions at the design stage of power supply systems.

Fire-resistant fluids and lubricants are products that are used in various industries or energy sector to ensure the reliability and safety of equipment operating under high temperature and pressure conditions. Aspects of the use of fire-resistant fluids (hydraulic or lubricating agents), including those based on xylenol, in the Russian Federation energy industry (control and lubrication systems for automatic control systems of steam or gas turbines), and the problems of switching from imported materials to domestic analogues are considered. The range of issues raised at the All-Russian Scientific and Technical Conference “Modern trends in the development of the market for fire-resistant turbine oils and the record of their operation at thermal power plants and nuclear power plants,” held in March 2023, as well as the decisions made there, are covered. Besides, measures taken by energy companies to legitimize the use of domestic fire-resistant fluids for operation in thermal power equipment in Russia are indicated. The results of laboratory studies of new domestic fire-resistant fluids are presented, conclusions are drawn about the possibility of use, operation, and approval of new domestic lubricating or hydraulic fluids in the energy sector. The article was prepared in cooperation between two large electric-heat-generating companies and with the participation of Power Machines, PJSC. One of the goals set by the authors was to promote the production of domestic fire-resistant fluids synthesized from raw materials available in the Russian Federation, ensuring the reliable functioning of oil systems of turbine units.

An original view on overcoming the consequences of man-made disasters and others crisis situations in the energy sector is presented with the help of a specific and little-studied spin doctoring technology. The article comprehensively reveals the concept and role of spin doctoring, as an effective PR tool for anti-crisis communication, with the key functions and mechanisms of its application identified. Innovative spin doctoring practices are summarized, as implemented by one of the authors in the Russian electric power industry, nuclear energy and in relation to alternative generation projects in the conditions of agricultural business while working for the state corporations Rostec, Rosatom, VEB.RF, in the Rosseti electric grid holding and the Agropromkomplektatsiya group of companies. New methodological approaches to the theory of spin doctoring and practical recommendations are proposed for energy companies to implement in their crisis management activities. The researchers have provided in-depth analysis of the effectiveness of the use of special spin doctoring techniques by companies of foreign and domestic fuel and energy complex in man-made accidents and catastrophes, as well as in a number of socially significant technological incidents. Both positive and negative aspects of responding to crisis situations are considered. The results obtained in the course of the study can be used in the anti-crisis activities of management bodies and information policy and communications (public relations) departments of energy and related industries.