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Thermal power plants remain one of the main sources of environmental pollution. The deterioration of the quality of traditional carbon-containing energy resources leads to the need to develop technologies for co-combustion of biofuel and coal at small and large power plants. The paper proposes the concept of using solid waste from tire recycling by adding to the composition of the mixed fuel “coal – wood waste” as a substitute for coal slag, which is formed during the utilization of worn-out tires by pyrolysis. The aim of the work was to determine the possibility of increasing the calorific value of wood pellets by co-firing with pyrolysis slag instead of coal without increasing the burden on the environment. At the same time, the following tasks have been set: to determine the lowest combustion heat of mixed fuels and assess its change when replacing coal with slag; to determine moisture content, total sulfur content, volatile matter yield, ash content of mixed fuels according to standard methods; to assess the change in these parameters when replacing coal with slag at the same component ratios; to determine the optimal ratios of components in mixed fuels, which will not increase the burden on the environment when replacing coal with pyrolysis slag. It has been determined that replacing coal with slag results in an increase in calorific value by 37–45 %, a decrease in ash content by 37–42 %, and an increase in the yield of volatile substances. At the same time, the sulfur content increases by 5.6–18 %. The use of traditional cleaning equipment is recommended in order to reduce the emission of sulfur dioxide. The research results make it possible to substantiate the possibility of replacing coal with slag in mixed fuels at certain ratios of components. A new direction of using solid products from recycling of rubber products, i.e. worn-out tires, has been proposed by the pyrolysis method in mixed fuels “slag-wood pellets” for small and medium-sized power plants.

The article presents the technique of an estimation of efficiency of use of potential heat output of an auxiliary boiler (AB) to improve electric capacity and manoeuvrability of a steam turbine unit of a power unit of a nuclear power plant (NPP) equipped with a water-cooled water-moderated power reactor (WWER). An analysis of the technical characteristics of the AB of Balakovo NPP (of Saratov oblast) was carried out and hydrocarbon deposits near the NPP were determined. It is shown that in WWER nuclear power plants in Russia, auxiliary boilers are mainly used only until the normal operation after start-up whereas auxiliary boiler equipment is maintained in cold standby mode and does not participate in the generation process at power plants. The results of research aimed to improve the systems of regulation and power management of power units; general principles of increasing the efficiency of production, transmission and distribution of electric energy, as well as the issues of attracting the potential of energy technology sources of industrial enterprises to provide load schedules have been analyzed. The possibility of using the power complex NPP and the AB as a single object of regulation is substantiated. The authors’ priority scheme-parametric developments on the possibility of using the thermal power of the auxiliary boilers to increase the power of the steam turbine of a nuclear power plant unit equipped with WWER reactors unit during peak periods, as well as the enthalpy balance method for calculating heat flows, were applied. The surface area of the additional heater of the regeneration “deaerator – high pressure heaters” system and its cost were calculated. On the basis of calculations, it was shown that the additional power that can be obtained in the steam turbine of the NPP with a capacity of 1200 MW due to the use of heat of the modernized auxiliary boiler in the additional heat exchanger is 40.5 MW. The additional costs for the implementation of the heat recovery scheme of the auxiliary boiler at different prices for gas fuel and the resulting system effect were estimated in an enlarged way. Calculations have shown the acceptability of the payback period of the proposed modernization.

Introduction. Improving the quality and operational reliability of welded structures of power equipment is an urgent task of welding production. Its solution is possible on the basis of the development or selection of advanced methods and technologies of electroslag welding (ESW), which eliminate the causes of the formation of tempering cracks (TC) in thick-plate welds. This paper considers a comparative assessment and recommendations on the selection of such advanced ESW methods. The work objectives are to solve the problem of forming a fine-grained, uniform, crack-resistant metal structure of a welded joint with high mechanical characteristics and to reduce the negative impact of the ESW thermal cycle on the base metal. The solution to this problem is possible on the basis of a reasonable choice of methods and technologies for ESW with regulated (controlled) thermal cycle. Materials and Methods. A comparative analysis of advanced methods and technologies of ESW with a controlled thermal cycle is carried out; a comparison of their pros and cons is provided; practical recommendations on the selection of advanced methods for controlling the thermal cycle parameters are offered. Results. It is shown that moderate heat input at high-speed ESW in a narrow gap provides a single pass to form a welded joint with a finer-grained structure and high mechanical properties compared to the in-house technologies of ESW and automatic submerged-arc welding. Recommendations for practical use of the method in welding production are given. Discussion and Conclusions. The results obtained are recommended to be used in the development of ESW technology for thick-sheet welded structures of nuclear and thermal power equipment that enables to abandon postwelding heat treatment (normalization and high tempering).

The purpose of this study was to assess the restoration of vegetation in the reclaimed bowls of the ash dumps of the Chita TPP-1. The object of the research was the vegetation cover formed on two worked-out cups of the ash dumps, which were reclaimed in 2010 – the “young dump” and in 1986 – the “middle-aged dump”. The background was natural phytocenoses that were not subjected to ash and slag waste storage, located outside the dumps a short distance from them. Materials and methods. According to generally accepted methods for botanical research 9 plots where the characteristics of the floristic composition was performed were laid on each reclaimed bowl. The identified species were divided into families; their belt-zonal and ecological classification was performed. Results. The assessment of vegetation cover formation on two worked out ash and slag dump of Chita TPP-1 showed that vegetation is characterized by an unsatisfactory ability to recover, regardless of the terms of reclamation. This is reflected in a 4-fold decrease in projective cover in the territory reclaimed over 30 years ago and more than 7-fold in the territory reclaimed about 10 years ago, as well as a significant (2 and 3.5-fold) decrease in species diversity. In addition, the territory of the “young dump” is characterized by significant areas of eroded areas. According to the belt-zonal and ecological classification, it was revealed that phytocenoses of the forest-steppe, actually steppe, mountain-steppe type are formed on the “young” and “middle-aged” dumps, this corresponds to adjacent undisturbed phytocenoses. Conclusions. The research results indicate the need to change existing approaches to the reclamation of waste lands of ash and slag dumps of Chita TPP-1.

The paper considers spatial organization of energy facilities with an emphasis on modern practice of the Republic of Belarus. The efficiency of enterprise operation in any industry including power industry is largely due to their architectural and planning organization. Knowledge of mechanisms and specific features of the changes taking place here makes it possible to justify a promising strategy for project activities, and therefore, it allows to manage development processes of the industry and thereby avoid many negative consequences. Energy facilities are a typological unit of industrial architecture, their formation has been started due to transition of industrial production to electric energy. Today the typology shows functional approach in architectural shaping, it includes a fairly large variety of constituent units and demonstrates a tendency towards diversification. In Belarus energy facilities in the architectural aspect of their classification are limited mostly to thermal power plants operating on different types of fuel. Currently the diversification is developing in the following areas: construction of hydropower facilities (small plants on reservoirs, medium power plants, low-pressure plants, run-of-the-river hydraulic power stations), alternative energy (wind power stations, photovoltaic power stations and biogas plants) and conventional energy (thermal power plant, mini-combined heat and power plant operating on renewable fuel). The results of Belarusian practice in construction of all types of facilities (hydropower, alternative and conventional energy), peculiarities of the architectural and planning organization of facilities at the current stage, correlation with global trends in the development of industrial architecture have been characterized in the paper. The paper has determined typological features of alternative energy facility architecture, opportunities and directions for implementation of architectural approaches, problems and prospects to develop scientific support for the project process.

Air cooling devices are heat exchange units that are widely used in practice. However, they have a number of disadvantages due to the low value of the heat transfer coefficient from the air and the high resistance of finned tube bundles, which leads to large dimensions and the metal content of the device itself, to the need to develop a high power ventilator drive, but also to the need to demonstrate reduced energy efficiency. The objective of the present work is to determine optimal geometric sizes of finned flat heat exchange tubes manufactured by the techniques of extrusion and deforming cutting that reduce the weight and size characteristics of the heat exchange section of air cooling devices. The experimental studies of seven various samples of heat exchange sections, being different in fin pitch and height, tube section width, flat tube height and a number of inner channels, have determined the performance of each section with the use of the following criteria: thermal power, thermal efficiency, specific thermal heat transfer resistance, M. V. Kirpichev and V. M. Antuf’ev’s criteria. The obtained experimental data and the analysis of the passive method of enhancement in the near-wall area of the heat transfer surface finned by deforming cutting has shown that sample No 5 has maximum value of the performance criteria when the maximum height of a fin is 0.008 m and the minimum pitch of a fin is 0.0025 m over the investigated sample range. Thus, when the sizes of an oil air cooling device are maintained by using the amended heat transfer section of sample No 5, the amount of removed heat can be increased or the mass and dimensions of the device can be decreased while maintaining thermal power and, as a result, the power consumption for pumping can be decreased and the thermal-hydraulic performance of the device as a whole can be increased.

Objectives. This study was aimed at determining the actual flow rate of a gaseous working fluid by the pressure drop in the constriction device with its changing parameters (speed, pressure, temperature, gas composition).Method. Since the pycnometric method provides high accuracy in determining the density and is simpler than the calorimetric method for determining the calorific value, the value of the latter can be checked using the dependence proposed in the article. In the event of a discrepancy between the calculated value of the calorific value and the experimentally obtained value of more than 0.5%, the determination of the calorific value and the density should be repeated. The relationship between the density and calorific value of a gas is subject to verification and refinement when gas from other fields is used. In all cases, a sampler should be used to accumulate an average gas sample over an appropriate period of time. The methodological error in calculating the amount of gaseous working fluid can be eliminated or reduced by using a computer as part of an automated heat supply enterprise management system.Results. It was established that the calorific value of energy fuels non-linearly depends on the hydrogen and carbon contained therein; a formula has been developed to describe this relationship. When studying the energy characteristics of fuels, a previously unknown regularity was established: hydrocarbons ethylene, benzene and annelated hydrocarbons (naphthalene, anthracene, naphthacene, etc.) form the homologous series CnH(n+6)/2 with the homological difference C4H2, while all other series of hydrocarbons have a homological difference CH2.Conclusion. The greatest difficulties consist in accounting (measuring) the amount of energy contained in the fuel used at TPPs, mainly natural gas, and the coolant, since there are no appropriate technical means for direct measuring the amount of a particular type of energy. The developed theoretical provisions make a certain contribution to the development of the scientific foundations of heat and gas supply, increase accuracy and reduce the complexity of calculating the technical and economic indicators of thermal power plants and boiler houses.

The paper considers the main trends in the development of the world market of solar photovoltaics over the past few years. It is shown that the industry is a very rapidly evolving one among the branches of renewable energy and modern industries as a whole. It is obvious that the prime cost of the of solar energy being produced is rapidly approaching the price of electricity generated by traditional methods at nuclear power plants and thermal power plants. The aspects of the development of the efficiency of modern research solar cells made of various materials using innovative technological solutions based on the data provided by the National Laboratory for Renewable Energy (NREL, USA) in 2017 are noted. For the convenience of analysis, the research solar cells are divided into four technological groups. The advantages and disadvantages of solar cells, including the specific features of their production and prospects for development are considered separately for each group; the maximum efficiency for the year 2017 is estimated. A possible alternative to the future development of modern high-performance single-transition solar cells is the use of fundamentally new materials based on nanoheteroepitaxial structures with quantum dots. The possibilities of absorption (processing) by such structures of both short-wave radiation and long-wave part of the solar radiation spectrum for the purpose of generation of electric energy by increasing the efficiency of solar cells on their basis have been demonstrated. The optimal materials for their production and the principles of action of high-performance solar cells on their basis have been considered. The prospects of manufacturing nanoheteroepitaxial structures with quantum dots by liquid-phase epitaxy with pulse cooling of the substrate have been substantiated.

Анализ прогнозов специалистов показывает, что рост потребления электроэнергии в мире до 2030 г. составит 2,4 %. На сегодняшний день вырабатываемая на тепловых электрических станциях энергия составляет 2/3 от общей вырабатываемой всеми источниками. Большинство этих ТЭС в качестве топлива используют уголь. Доля ТЭС, использующих это топливо, - 40 %. При сжигании угля происходит интенсивное выделение загрязняющих веществ, таких как NOx и SOx, основные последствия которого: ухудшение состояния здоровья человека, смог, кислотные дожди, парниковый эффект и пыление. Одним из новых инновационных решений экологических проблем угольной энергетики может стать сжигание биомассы (отходы лесопиления и лесного хозяйства). По оценкам специалистов объем запасов древесины в России превышает 82·109 м3 и составляет 25 % от мировых запасов. Отходы ее переработки составляют более 30·106 м3 в год. Интерес к использованию древесной биомассы также обуславливается постоянно возрастающими требованиями по экологичности объектов теплоэнергетики. Цель: экспериментальное установление зависимостей условий (минимальных температур) и характеристик (времен задержки) зажигания от вида древесной биомассы и её влагосодержания на примере четырех достаточно доступных и широко распространенных видов древесины (наиболее калорийной и поэтому перспективной для теплоэнергетики). Объект: сухая и насыщенная влагой древесина четырех видов (кедр, лиственница, сосна и осина). Экспериментальные исследования проведены для древесных частиц с относительной влажностью: 5, 30 и 45 %. Метод: экспериментальное определение с использованием высокоскоростной видеокамеры Photron FASTCAM СА4 временных характеристик процессов зажигания частиц древесины в условиях, соответствующих по интенсивности нагрева камерам сгорания паровых и водогрейных котлов; регистрация температуры среды с использованием хромель-алюмелевых термопар. Результаты. Приведены выполненные с целью обоснования ресурсуэффективности использования в теплоэнергетике древесной биомассы (как базового топлива паровых и водогрейных котлов) результаты экспериментальных исследований процессов зажигания сухих и влажных частиц четырех видов древесной биомассы в среде нагретого до высоких температур воздуха. Установлено существенное влияние вида древесины на условия и характеристики зажигания её одиночных частиц. Также установлено значительное влияние влажности на времена задержки зажигания частиц исследованных видов биомассы. Такие времена, соответствующие древесине в естественном состоянии, в 3-4 раза превышают во всем (достаточно широком) диапазоне изменения значимых для практики температур времена задержки зажигания сухих частиц древесины. Установленные в проведенных экспериментах закономерности иллюстрируют перспективность использования в теплоэнергетике древесной биомассы как основного топлива или компоненты древесно-угольной смеси. Analysis of experts' forecasts shows that the growth in global electricity consumption until 2030 will be 2,4 %. Today, the energy generated at thermal power plants is 2/3 of the total energy generated by all sources. For most thermal power plants, coal is the main fuel. The share of thermal power plants burning coal reaches 40 %. Burning coal leads to intense emissions of nitrogen oxides and sulfur, the main consequences of which are deterioration in human health, smog and acid rain. One of the new solutions to the environmental problems of the energy industry is the combustion of biomass (sawmill and forestry waste). According to experts, the volume of timber reserves in Russia exceeds 82·109 m3 and accounts for 25 % of the world reserves. Waste from its processing is more than 30·106 m3 per year. Environmental requirements for heat and power facilities are constantly growing. This determines the interest in biomass use. The main aim of the research is to determine experimentally the dependences of ignition delay times during high-temperature heating of woody biomass of different moisture content using the example of four fairly accessible and widespread wood species (the most highcalorie and, therefore, promising) for heat power engineering. Object: dry and moisture-saturated wood of four types (cedar, larch, pine and aspen). Experimental studies were carried out for wood particles with relative humidity: 5, 30 and 45 %. Methods: experimental determination of the ignition temporal characteristics of wood particles under conditions corresponding to the intensity of heating to the combustion chambers of steam and hot water boilers using a high-speed video camera Photron FASTCAM CA4; registration of medium temperature using chromel-alumel thermocouples. Results. The paper introduces the results of the experimental studies of ignition of dry and wet particles of four type of woody biomass in the environment of air heated to high temperatures in order to substantiate the resource efficiency of using woody biomass (as the base fuel of steam and hot water boilers). A significant effect of the wood type on the ignition conditions and characteristics of its single particles was established. A significant influence of humidity on the ignition delay times of particles of the studied types of biomass was established as well. Such times, corresponding to wood in its natural state, are 3-4 times higher in the entire (rather wide) range of change of temperatures significant for practice, the ignition delay times of dry wood particles. The regularities established in the conducted experiments illustrate the prospects of using woody biomass in heat power engineering as the main fuel or components of a charcoal mixture.

Одной из наиболее актуальных проблем современности является экологическая безопасность. Загрязнение атмосферы Земли в последние десятилетия обусловлено в значительной степени работой тепловых электрических станций, сжигающих уголь, на территориях наиболее развитых государств (США, Китай, Индия и др.). Использование нового класса топлива - био-водоугольного - может позволить существенно снизить выбросы антропогенных газов, образующихся при сжигании углей в топках паровых и водогрейных котлов, в атмосферу Земли, расширить сырьевую базу современных тепловых электрических станций и повысить в целом ресурсоэффективность угольной теплоэнергетики. Цель: исследование влияния концентрации древесной биомассы в жидких композиционных топливах на интегральные характеристики процесса зажигания капель био-водоугольных топлив в условиях высокотемпературного нагрева. Объект: водоугольная суспензия на основе угля марки Т, воды и еловой хвои. Экспериментальные исследования проведены при следующих массовых концентрациях угля и биомассы: 50/0 %, 45/5 %, 40/10 %, 35/15 %, соответственно (50 % - вода). Метод: экспериментальное определение с использованием высокоскоростной видеокамеры Photron FASTCAM СА4 временных характеристик процессов зажигания капель био-водоугольных суспензий в условиях, соответствующих по интенсивности нагрева камерам сгорания паровых и водогрейных котлов; регистрация температуры среды с использованием хромельалюмелевых термопар. Результаты. Установлено влияние массовой концентрации лесного горючего материала на времена задержки зажигания (tign) водоугольных топлив. Показано, что при содержании в топливной композиции 15 % биомассы времена задержки зажигания уменьшаются более чем в три раза по сравнению с водоугольным топливом без добавления биомассы при относительно низких температурах топочной среды. Результаты выполненных экспериментальных исследований также являются базой для развития моделей горения жидких композиционных топлив. One of the most pressing problems of our time is environmental safety. The pollution of the Earth's atmosphere in recent decades is caused by work at thermal power plants burning coal in the territories of the most popular states (USA, China, India, etc.). The use of a new class of fuel - bio-water-coal - can significantly reduce emissions of man-made gases, generated during combustion of coal in the furnaces of steam and hot water boilers, into the Earth's atmosphere, expand the raw materials base of the modern thermal power plants and increase the resource efficiency of coal-fired power systems. The aim of the research is to study the influence of the concentration composition on the integral characteristics of ignition of the drops of the biohydrocarbon fuels under high-temperature heating. Object: a water-coal suspension based on brand T coal, water and spruce needles. In the course of the experimental studies, the following mass concentrations of coal and biomass were considered 50/0 %, 45/5 %, 40/10 %, 35/15 %, respectively (50 % - water). Method: experimental determination using the high-speed Photron FASTCAM CA4 video camera of the temporal characteristics of ignition of drops of the bio-water-coal suspensions under conditions corresponding to the heating intensity of the combustion chambers of the steam and hot water boilers; registration of medium temperature using chromel-alumel thermocouples. Results. The effect of mass concentration of forest combustible material on ignition delay times (tign) of water-coal fuels has been established. It was shown that when the fuel composition contains 15 % of biomass, the ignition delay times are reduced by more than three times compared with water-coal fuel without adding biomass at relatively low temperatures of the combustion medium. The results of experimental studies are also the basis for development of combustion models of liquid composite fuels.

В данной работе изложена сущность подхода к созданию электрической части ТЭС. Была выбрана оптимальная структурная схема и оборудование. Были рассчитаны токи короткого замыкания. Были разработаны главная схема электрических соединений и схема собственных нужд. Задачи, которые решались в ходе исследования: 1.Выполнено проектирование электрической части тепловой электростанции (ТЭС). 2.Выбрана оптимальная структурная схема и основное электрооборудование. 3.Рассчитаны токи короткого замыкания. 4.Выбраны электрические аппараты и проводники. 5.Разработана главная схема электрических соединений., In the given work, essence of the approach to creation of electrical part of heat electropower station is stated. The optimal block diagram and equipment was selected. The main circuit of electrical connections and the circuit of own needs were developed. The tasks that were solved during the study: 1. The design of the electrical part of the thermal power plant (TPP) was completed. Tasks that were solved during the study: 1. The design of the electrical part of the thermal power plant (TPP) was completed. 2. The optimal block diagram and basic electrical equipment were selected. 3. Short-circuit currents calculated. 4. Selected electrical apparatus and conductors. 5. The main circuit of electrical connections has been developed.

Актуальность исследования обусловлена необходимостью поиска оптимальных решений по организации сжигания полифракционного пылеугольного топлива на действующих и новых тепловых электрических станциях с учетом снижения выбросов вредных веществ, в частности оксидов азота. За последнее десятилетие значительно выросли экологические требования, направленные на регулирование выбросов от угольных электростанций в атмосферу, которые были спроектированы в целях повышения тепловой эффективности. В настоящее время проблема совершенствования экологических параметров ТЭС в России обостряется тем, что большинство действующих станций не удовлетворяют современным экологическим нормам и требованиям. Цель: установить влияние организации сжигания твердого топлива на топочные процессы при минимальной возможной модернизации действующего парового котла с использованием низкоэмиссионных горелочных устройств. Объекты: топочная камера энергетического котла в проектном исполнении и в варианте с заменой проектных горелочных устройств на низкоэмиссионные. Методы. Численное исследование проведено с использованием пакета прикладных программ Ansys Fluent v.12.1. Математическое моделирование физико-химических процессов в топочной камере на основе Эйлеро-Лагранжева подхода, который позволяет выявить главные взаимодействия процессов переноса частиц. Математические модели горения угольной пыли с кинетическими параметрами заданы и включены в код в качестве пользовательских функций. Результаты. Разработана математическая модель на основе пакета прикладных программ с качественным представлением сложных физико-химических процессов в объеме топочной камеры. Дана оценка возможности организации сжигания каменного угля в низкоэмиссионных горелочных устройствах с учетом оптимального соотношения первичного и вторичного воздуха без изменения установочных углов лопаточных заверителей. В данном исследовании установлено снижение концентрации оксидов азота на 14 % при замене проектных двухканальных вихревых горелочных устройств на низкоэмиссионные. The relevance. It is necessary to find optimal solutions for organizing the combustion of polyfractional pulverized coal fuel, taking into account the reduction of emissions of harmful substances, in particular nitrogen oxides, at existing and new thermal power plants. Currently, the problem of increasing the environmental parameters of thermal power plants in Russia is very acute, since most of the existing plants do not meet modern environmental standards and requirements. The aim of the research is to determine the impact of the organization of solid fuel combustion using low-emission burners with possible modernization on combustion and to assess the possibility of efficient combustion by increasing the rate of primary air. Object: furnace chamber of the power boiler in the design version and with the replacement of the design burners with low-emission ones. Method. The numerical study was performed using the Ansys Fluent V.12.1 software package, mathematical modeling of physical and chemical processes - in a furnace chamber based on Euler-Lagrangian approaches. Result. A mathematical model is developed based on a package of application programs with a qualitative representation of complex physical and chemical processes in the volume of the furnace chamber. The estimation of the possibility of organizing the burning of Ekibastuz coal in low-emission burners with the optimal ratio of primary and secondary air without changing the installation angles of the blade swirlers is given.

Объектом настоящего исследования является участок ограждающей дамбы ПК 11-13 золошламонакопителя в г. Темиртау, Республика Казахстан. Предмет исследования – устойчивость гидротехнического сооружения. Основная цель работы – разработать технические решения по ремонту участка дамбы для обеспечения устойчивости ограждающей дамбы. Задачи – определение причин проблемы на исследуемом участке, обоснование и описание технических решений, расчет скважин системы водопонижения, расчет устойчивости ограждающей дамбы на строительный период и эксплуатационный период., The object of the research is the section 11-13 of the ash dump of the dam in Temirtau City, Republic of Kazakhstan. The subject of the research is the stability of the structure. The aim is to develop technical solutions for the maintenance and repair of the section in order to ensure the stability of the dam. The objectives are to identify the causes of the issues at the section, to justify and describe technical solutions, to calculate the amount of the lowering wells and to estimate filtration and stability of the dam during the reconstruction and operation period.

Power generating units of heat and power plants equipped with steam boilers that have supercritical and high steam parameters and the system of steam pipelines produce the major portion of electric power in Ukraine. This scientific paper describes the peculiarities of the use of heat-resistant pearlitic steels of 12Х1МF, 15Х1М1F, 12Х2МFSR grades and others. These steels are used to manufacture the elements for the steam pipelines of thermal power plants whose service life has already run out and it is a vital problem at the moment. This scientific paper looks into the reasons for the appearance of damages and degraded operating performances of the welded pipe junctions of steam pipelines. The research data obtained during the studies of the structure and mechanical properties of the welded junctions of steam pipelines have been given. Consideration was given to the factors that affect welded junctions during their long-term operation. It was established that the welded junctions made of heat-resistant pearlitic steels degrade during their long-term operation following the creep crack formation mechanism. It was established that the welded junctions of steam pipelines with the accrued operating time of 270.000 hours and an increased number of the start-stop cycles of power generating units are characterized by an increased probability of faults following the fatigue mechanism. It depends to a great extent on the local concentration of stresses in the structures of welded junctions and their structural state.

Objectives The aim of the study is to generalise the results of the application of technologies and means for organising pulse coolant flow within a district heating system in order to increase its energy efficiency based on the organisation of local hydraulic shocks and the subsequent use of their energy to ensure the purification of heat energy equipment, intensify the heat transfer process and realise the possibility of transforming the available head from one hydraulic circuit to another. Methods Substations connecting the thermal power installations of consumers with heat networks via dependent and independent schemes are analytically generalised. The use of pulse coolant circulation is proposed as a means of overcoming identified shortcomings. Results Principal schemes of substations with pulse coolant circulation for dependent and independent connection of thermal power installations are detailed. A detailed description of their operation is given. The advantages of using pulse coolant circulation in substations are shown. The materials reflecting the results of the technical implementation and practical introduction of this technology are presented. Conclusion Theoretical analysis of the operation of the basic schemes of substations with pulse coolant circulation and the results of their practical application, as well as the materials of scientific works devoted to the use of the energy of a hydraulic impact and the study of the effect of pulse coolant flow on thermal and hydrodynamic processes, have yielded a combination of factors reflecting technical and economic rationality of application of pulse coolant circulation.

The production, transformation, transmission, distribution and consumption of electricity is one continuous process. The change of the load, i.e. the level of energy consumption, should cause a corresponding change in the level of generated energy. It means that the power system should be a balance of produced and consumed energy, taking into account technological cost of conversion, transmission and distribution. Otherwise, electric power quality indicators will be violated. For example, at infringement of balance of active power the frequency in the grid will have a value different from 50 Hz. One of the automatic devices on the lowest rung in the hierarchy of automatic dispatcher control system of frequency and power interchange is the system of automatic control of power units (SACPU). It is a comprehensive and complex device, which consists of several connected together simpler systems, governing all thermal power devices of a power unit. SACPU ought to regulate the active power of the unit and participate in primary frequency regulation in the network with a given accuracy and sensitivity; also, it ought to be adequately fast. At the same time, this device should be simple from the point of view of technical implementation, easy to use, allow one to maintain a high level of efficiency, reliability, durability and environmental performance of the units. To satisfy all these requirements (often conflicting) simultaneously, SACPU should have a certain structure, which depends on the composition and characteristics of heat power equipment of the power unit and on operating modes. The analysis of known SACPU have demonstrated that they are unable to fully provide the requirements of the modern standards for quality control of frequency and power, i.e. the SACPU models are still in need of structural and parametric optimization on the basis of the proximate methods developed at the Belarusian National Technical University.

В статье рассматривается возможность реконструкции парогенератора БКЗ220110 Жезказганской ТЭЦ, на которой после демонтажа ширмового пароперегревателя, а также части первой ступени конвективного пароперегревателя возникли серьезные проблемы с обеспечением температурного режима третьей и четвертой ступеней пароперегревателя. Для решения возникших проблем предлагается реконструкция, которая позволит повысить паропроизводительность до 240 т/ч, используя в качестве топлива борлинский каменный уголь, увеличить надежность работы котлоагрегата и снизить выбросы NOx до величины менее 470 мг/нм3, при 1,4., The article discusses the possibility of reconstructing BKZ220110 steam generator of the Zhezkazgan CHPP, where serious problems arose in ensuring the temperature regime of the third and fourth stages of the superheater after dismantling the screen superheater, as well as part of the first stage of the convective superheater. To solve the problems, reconstruction is proposed aimed at increasing steam production up to 240 t/h with Borlin coal as fuel raising the reliability of the boiler and reducing NOx emissions to less than 470 mg/nm3 where 1.4., №8(86) (2019)

Микро электростанция с двигателем с внешним подводом теплоты будет вырабатывать электрическую энергию для собственных нужд предприятия используя тепловые потери коксового производства. Основой микро тепловой электростанции является двигатель с внешним подводом теплоты работающий по принципу Стирлинга. В своей работе мы учитываем положительные результаты, опыт и достижения зарубежных, для создания собственной конструкции. В статье приведены некоторые результаты исследований по эффективности работы двигателя с внешним подводом теплоты. Также в статье показаны основные технические характеристики модели. Для достижения высокого КПД двигателя необходимо добиться эффективного нагрева и охлаждения тела. В статье предоставлены пути решения данных проблем. Кроме того, в статье есть моделирование процесса увеличения давления при помощи компьютерной программы, что наглядно показывает все рабочие характеристики двигателя., A micro powerplant with an engine with an external heat supply generates electrical energy for the company's own needs using heat loss from coke production. The basis of a micro thermal power plant is an external heat supply engine based on the Stirling principle. In this paper, authors take into account the positive results, experience, and achievements of foreigners, to create own design. The article presents some results of research on the efficiency of the engine with external heat supply. The article also shows the main technical characteristics of the model. In order to achieve high engine efficiency, it is necessary to get effective heating and cooling of a body. The article provides solutions to these problems. In addition, the article presents a simulation of the process of increasing pressure with the application of a computer program, which clearly shows all the performance characteristics of the engine., №1(79) (2019)

Further improvement of natural gas usage in power industry is associated with transition to the combined-cycle gas technology, primarily at combined heat and power plants (CHP). Renovation of technology of conversion of fuel energy into heat and electricity flows is effective while it is performed simultaneously with the elaboration of thermal circuits of CHP by insertion heat accumulators and absorption lithium bromide heat pumps (ALBHP) in the structure of CHP; the mentioned insertion amends thermodynamic as well as economic and environmental indicators of CHP renovation and also develops CHP maneuverability. The ability of CHP to provide heat in required quantity, their capacity to change electricity generation output without excessive fuel consumption is extremely relevant for the energy system that incorporates thermal power plants as dominating component. At the same time the displacement of traditional electrical power regulators take place. Implementation of projects of this kind requires the elaboration of CHP flow diagram calculation methods and determining relevant indicators. The results of the numerical study of the energy characteristics of CHP with the aid of the topological models of the existing heat flow diagrams of CHP that incorporate ALBHP for recovery of low-temperature waste of heat flows of systems of cooling water circulating are presented in the article. An example of calculation, the results of the CHP thermodynamic efficiency evaluation, the change of the energy characteristics for different modes of operation of CHP caused by implementation of ALBHP are shown. The conditions for the effective application of lithium bromide absorption heat pumps are specified, as well as the rate of increase of thermodynamic efficiency; the changes of maneuverability of CHP with high initial parameters are identified, the natural gas savings in The Republic of Belarus are determined.

In order to reduce the temperature of cooling water and increase the efficiency of use of power resources the main directions of modernization of systems of technical water supply with cooling towers at steam power plants are presented. The problems of operation of irrigation systems and water distribution systems of cooling towers are reviewed. The design of heat and mass transfer devices, their shortcomings and the impact on the cooling ability of the cooling tower are also under analysis. The use of droplet heat and mass transfer device based on the lattice polypropylene virtually eliminates the shortcomings of the film and droplet-film heat and mass transfer devices of the cooling tower, increasing lifetime, and improving the reliability and efficiency of the operation of the main equipment of thermal power plants. The design of the water distribution devices of cooling towers is also considered. It is noted that the most effective are water-spattering low-pressure nozzles made of polypropylene that provides uniform dispersion of water and are of a high reliability and durability.

Availability of, and access to, coal is a crucial element of modern economies and it helps pave the way for human development. Accordingly, the thermal power sector and steel industries have been given a high priority in the national planning processes in India and a concerted focus on enhancing these sectors have resulted in significant gain in generation and availability of electricity and steel in the years since independence. To meet the need of huge demand of power coal is excavated. The process of excavation to the use of coal is potential enough to degrade the environment. Coal Mining is a development activity, which is bound to damage the natural ecosystem by all its activities directly and ancillary, starting from land acquisition to coal beneficiation and use of the products. Huge areas in the Raniganj and Jharia coal field in India have become derelict due to abandoned and active opencast and underground mines. The study is pursued to illustrate the facts which show the urgent need to clean coal mining in India.

Запропоновано модель енергозберігаючого керування нагнітачами (насоси та вентилятори) теплових електричних станцій. Показано фактори, що впливають на енергетичну ефективність роботи нагнітача. Складено векторну структурну схему нагнітача та отримано аналітична залежність енергетичних втрат від основних технологічних параметрів нагнітача. Встанавлені залежності між основними параметрами насосної установки – тиском, об’ємною подачею, параметрами керуючого впливу – частотою обертання насоса та положенням регулюючої засувки., Предложена модель энергосберегающего управления нагнетательными установками (насосы ивентиляторы) тепловых электрических станций. Показаны факторы, оказывающие влияние наэнергетическую эффективность работы нагнетателя. Составлена векторная структурная схеманагнетательной установки и получена аналитическая зависимость энергетических потерь от основныхтехнологических параметров нагнетательной установки. Установлены зависимости между основнымипараметрами насосной установки – давлением, объемной подачей, параметрами управляющеговоздействия – частотой вращения насоса и положением регулирующей задвижки., The model of energy saving control of discharge units (pumps and fans) of thermal power stations has been proposed. The factors that affect the power efficiency of the supercharger operation have been shown. The influence of the technical performances of pipeline systems on the power station efficiency has been demonstrated. The function of power losses in the supercharger that can be varied in real time depending on the changes of power responses in the discharge units (bearing wear, a change in the Reynolds number, etc.) has been plotted. The vectorial block diagram of the discharge unit has been elaborated and the analytical dependence of power losses on major process parameters of the discharge unit has been obtained. The dependencies between the basic parameters of pump station, in particular, pressure, volumetric supply, control action parameters and pump rotation frequency and control slide position have been established. The experimental energy response of the real centrifugal pump mounted at the thermal power station was used as an example to demonstrate the technique used for the determination of the power efficiency of pump operation varying the rotation frequency and the methods of the determination of the pump operation range, which provides for the minimum power losses has been given.

В работе выполнено проектирование электрической части конденсационной электростанции. Выбрана оптимальная структурная ÑÑ ÐµÐ¼Ð° и основное электрооборудование. Рассчитаны токи короткого замыкания. Выбраны электрические аппараты и проводники. Разработана главная ÑÑ ÐµÐ¼Ð° ÑÐ»ÐµÐºÑ‚Ñ€Ð¸Ñ‡ÐµÑÐºÐ¸Ñ ÑÐ¾ÐµÐ´Ð¸Ð½ÐµÐ½Ð¸Ð¹ и ÑÑ ÐµÐ¼Ð° ÑÐ¾Ð±ÑÑ‚Ð²ÐµÐ½Ð½Ñ‹Ñ Ð½ÑƒÐ¶Ð´., This paper focuses on designing the electrical system of a condensing power. The appropriate block diagram and the basic electrical equipment are presented; short circuit currents are calculated; electrical appliances and conductors are covered in this study. The main scheme of electrical connections, as well as auxiliaries schemes elaborated in the course of the work are presented.

Выполнено численное моделирование теплообмена при течении воды сверхкритического давления в семистержневой тепловыделяющей сборке. Проанализировано влияние изменения тепловой мощности и расхода теплоносителя на условия возникновения и развития режимов ухудшенного теплообмена. Виконано чисельне моделювання теплообміну при плині води надкритичного тиску в семистрижневій тепловиділяючій збірці. Проаналізовано вплив зміни теплової потужності і витрати теплоносія на умови виникнення і розвитку режимів погіршеного теплообміну. Numerical simulation of heat of supercritical pressure water flow in seven kernels fuel assembly is carried out. The effect of the thermal power and the coolant flow rate on the conditions of occurrence and development of degraded heat transfer modes is analyzed.

Целью данной работы является рассмотрение возможности сохранения генераторами Первомайской ТЭЦ устойчивости при потере возбуждения на время автоматического ввода резерва на секциях СН с использованием математической модели энергосистемы и динамической устойчивости для нормальных и наиболее тяжёлых схемно-режимных условий. В качестве метода исследования выбрано математическое моделирование с использованием современного программного обеспечения MatLab Simulink. Создана и верифицирована полная математическая модель Первомайской ТЭЦ. Проведен анализ характерных режимов для исследования динамической устойчивости. Оценена динамическая устойчивость работы генераторов для соответствующих нормативных возмущений., Purpose of this thesis is dynamic stability research for generators of Pervomayskaya Power Plant on condition of field loss during the automatic load transfer for auxiliary supplies sections using the mathematical model of power system and dynamic stability research on condition of the hardest electrical disturbances. The research method is mathematical modeling using MatLab Simulink software. Full mathematical model of Pervomayskaya Power Plant was created and verified. Typical modes were analyzed during dynamic stability research. Conditions of dynamic stability were estimated for generators on condition of standard disturbances.

Поставлена задача оптимизации режимов работы котельного оборудования тепловых электростанций по критерию минимума энергетических потерь и намечены пути её решения. Определены основные технологические параметры и внешние возмущения, оказывающие влияние на величину энергетических потерь в прямоточных котлах ТЭС. Составлена математическая модель задачи оптимизации режимов работы котлов по критерию минимума энергетических потерь. This scientific paper gives the definition of the formal optimization problem of operating conditions for the equipment of thermal power plants using the criterion of minimum power losses and defines the methods of its solution. The main process parameters and external perturbations that influence the value of power losses in the direct flow boilers of thermal power stations have been defined. The mathematical model of the optimization problem of operating conditions for the equipment of thermal power plants using the criterion of minimum power losses has been constructed.

Расчетное исследование ресурсных характеристик высокотемпературных корпусных элементов паровой турбины позволяет управлять остаточным ресурсом. Управление остаточным ресурсом обеспечивается изменением режимов эксплуатации, усовершенствованием тепловой схемы, удалением поврежденного металла, изменением конструкции в объемах расширенного капитального ремонта оборудования и т.д. Подача горячего пара соседних энергоблоков на передние концевые уплотнения ЦВД и ЦСД паровой турбины К-200-130 ЛМЗ вызовет улучшение ресурсных характеристик корпусов высокого и среднего давления более, чем на 50 %. Computational investigations of the resource characteristics of the high temperature casing elements of a steam turbine allows for the control of the residual resource. The control over the residual resource is exercised by changing operation modes, improving thermal circuit, removal of the damaged metal, changing the structure during the equipment overhaul, etc. The supply of hot steam from neighboring energy blocks to the front end seal of HPC and IPC of the steam turbine K-200-130 LMZ will result in the improvement of the resource characteristics of high and intermediate pressure casings by more than 50 %.

Актуальность работы обусловлена необходимостью создания высокоэффективных энергоблоков по одному из направлений, предусматривающему разработку конструкции пароперегревателя и технологии перегрева водяного пара до температур выше 800 ?С сверхкритического давления перед непосредственным вводом пара в турбоустановку. Цель работы. Исследование влияния соотношения расходных энтальпийных характеристик горючей смеси (CH4+O2) по составу, близкому к стехиометрии, и слабо перегретого водяного пара атмосферного давления на температуру реагирующих сред (продуктов сгорания в среде водяного пара), а также на качественный и количественный состав парогазовой смеси в диапазоне расходных характеристик стабильного и устойчивого горения. Методы исследования. В работе используются отработанные методики измерений всех параметров процесса в автоматизированном режиме сбора и обработки первичной информации: температуры, давления, расхода, состава газовой конденсированной фазы. Применяется проточный метод измерения концентрации продуктовых компонентов в режиме реального времени с погрешностью ±5 %. Результаты. Выявлено, что с повышением численного значения отношения горючей смеси к спутно подаваемому водяному пару происходит постепенное повышение роли реакции неполного окисления метана. Также имеется область, где будет происходить доминирующее влияние реакции полного окислении метана при незначительной паровой конверсии метана. Это обстоятельство может свидетельствовать об уменьшении доли водорода в продуктах горения на выходе из пароперегревателя (камеры сгорания). Термодинамический анализ горения метана и кислорода в среде водяного пара необходимо проводить с учетом возможного влияния процесса паровой конверсии метана в широком интервале температур, но в большей степени при температуре более 700 ?С. Паровая конверсия метана имеет место не только в непосредственной области смешения водяного пара на границе поверхности факела с продуктами сгорания, но и за фронтом пламени в объеме камеры сгорания. The relevance of the research is caused by necessity of making highly effective power-generating units on one of the directions, providing working out of a construction of the steam superheater and production engineering of steam overheat up to temperatures above 800 °С of the supercritical pressure before the immediate steam feeding into a turbine. The operation purpose: examination of the influence of enthalpic metering characteristics of a gas mixture (CH4+O2) close to stoichiometric composition, and feebly overheated steam of atmospheric pressure on the temperature of the reacting medium (products of combustion in the environment of steam), and also on qualitative and quantitative composition of a steam-gaseous intermixture over the range of metering characteristics of stable and resistant to burning. Research techniques. The authors used proved measurement techniques of all parameters of process in the automated mode of gathering and processing of the primary information: temperature, pressure, charge, composition of a gas condensed phase. The flowing method of concentration measuring of products in real time mode with a margin error ±5 % was also used. The relevance of the research is caused by necessity of making highly effective power-generating units on one of the directions, providing working out of a construction of the steam superheater and production engineering of steam overheat up to temperatures above 800 °С of the supercritical pressure before the immediate steam feeding into a turbine. The operation purpose: examination of the influence of enthalpic metering characteristics of a gas mixture (CH4+O2) close to stoichiometric composition, and feebly overheated steam of atmospheric pressure on the temperature of the reacting medium (products of combustion in the environment of steam), and also on qualitative and quantitative composition of a steam-gaseous intermixture over the range of metering characteristics of stable and resistant to burning. Research techniques. The authors used proved measurement techniques of all parameters of process in the automated mode of gathering and processing of the primary information: temperature, pressure, charge, composition of a gas condensed phase. The flowing method of concentration measuring of products in real time mode with a margin error ±5 % was also used.

Приведен анализ термодинамического цикла блока преобразования энергии модульной ядерной энергетической установки четвёртого поколения с высокотемпературным гелиевым реактором тепловой мощностью 250 МВт для совместного производства электроэнергии и водорода. Дается анализ влияния параметров парогенератора на показатели эффективности цикла. Наведено аналіз термодинамічної циклу блоку перетворення енергії модульної ядерної енергетичної установки четвертого покоління з високотемпературним гелієвим реактором тепловою потужністю 250 МВт для спільного виробництва електроенергії і водню. Дається аналіз впливу параметрів парогенератора на показники ефективності циклу. The analysis is presented considering thermodynamic cycle of the energy conversion unit of the fourth-generation modular nuclear power plant with a hightemperature helium reactor of 250 MWt thermal power designated for the combined production of electricity and hydrogen. The analysis is given providing influence of steam generator parameters on the thermodynamic cycle efficiency.

Предложена модель энергосберегающего управления нагнетательными установками (насосы и вентиляторы) тепловых электрических станций. Показаны факторы, оказывающие влияние на энергетическую эффективность работы нагнетателя. Составлена векторная структурная схема нагнетательной установки и получена аналитическая зависимость энергетических потерь от основных технологических параметров нагнетательной установки. Установлены зависимости между основными параметрами насосной установки – давлением, объемной подачей, параметрами управляющего воздействия – частотой вращения насоса и положением регулирующей задвижки. The model of energy saving control of discharge units (pumps and fans) of thermal power stations has been proposed. The factors that affect the power efficiency of the supercharger operation have been shown. The influence of the technical performances of pipeline systems on the power station efficiency has been demonstrated. The function of power losses in the supercharger that can be varied in real time depending on the changes of power responses in the discharge units (bearing wear, a changein the Reynolds number, etc.) has been plotted. The vectorial block diagram of the discharge unit has been elaborated and the analytical dependence of power losses on major process parameters of the discharge unit has been obtained. The dependencies between the basic parameters of pump station, in particular, pressure, volumetric supply, control action parameters and pump rotation frequency and control slide position have been established. The experimental energy response of the real centrifugal pump mounted at the thermal power station was used as an example to demonstrate the technique used for the determination of the power efficiency of pump operation varying the rotation frequency and the methods of the determination of the pump operation range, which provides for the minimum power losses has been given.

В статье отражена авторская позиция в отношении иерархии элементов системы управления конкурентоспособностью предприятий. Проанализированы ключевые факторы конкурентоспособности теплоэлектроцентралей (ТЭЦ) на рынках энергии. Предложена модель управления конкурентоспособностью ТЭЦ. The article reflects the author's position as to the hierarchy of elements of the company competitiveness management system. Key factors of thermal power stations competitiveness at the energy supply market are analyzed. A model to manage thermal power station competitiveness is put forward.