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One of the most effective methods aimed to improving the environmental safety is fuel oil combustion in the form of specially prepared water-fuel emulsions. The combustion of water-fuel emulsion in internal combustion engines makes it possible to reduce a rate of low-temperature corrosion at wall temperatures below the dew point temperature of sulfuric acid vapor, to install a condensing lowtemperature heating surface in the exhaust gas boiler that leads to increase the efficiency of boiler. Therefore, it is of great importance to assess the effect of the presence of condensate (water, acid) and pollution on these surfaces on the processes of NOx, SO2 absorption from exhaust gases. Investigations of SO2, NOx and particulate matter emission were carried out on the experimental installation for fuel oil and water-fuel emulsion combustion with different water content. Using condensing heating surface enables to reduce the concentration of NOx and SO2 by 65 %. Experimental studies have shown that condensing heating surface ensures the capture of up to 30 % of particulate matter from the exhaust gas flow.

For the design and planning of gas-fired boiler system, the load of gas-fired boiler is an important basic data. Load clustering analysis, combined with the application of data mining technology and gas boiler system, excavates the hidden load patterns in a large number of disordered and irregular loads, and classifies them, so as to solve many problems in gas boiler system. The current load clustering methods have more or less problems. The invention first carries out data PVA dimension reduction processing on the huge gas data, and then carries out cluster analysis. In the actual application of gas-fired boilers, the data objects we are faced with are usually unbalanced data sets. In order to solve the problem of sample imbalance, we use the FCM-SMOTE algorithm to oversample the clustered data to make the data set into a balanced data set.

Based on an example of a gas-fired boiler for an industrial user in Tianjin, the absorption heat pump technology was used to carry out energy-saving transformation of the above boiler. The actual test was carried out on the gas flow, exhaust gas temperature and other parameters from January 2, 2018 to February 26, 2018. And then, the thermal efficiency of the boiler was analysed. The results show that after the energy-saving transformation, the exhaust gas temperature of the gas-fired boiler can be reduced from 140 °C to about 40 °C, and the overall thermal efficiency of the boiler also rises from 89.5% to 101.3%, which is 13.2% higher than that before optimization. According to the economic analysis, the energy-saving reconstruction project can achieve an energy-saving economic benefit of 1.598 million yuan throughout the year, with obvious energy-saving and emission reduction benefits.

Measures to improve the energy efficiency of boiler houses must be carried out in a complex, taking into account the interconnection of all obtaining heat energyprocesses, their automation and greening. A number of experiments have been carried out on UHFheating, drying and subsequent ignition of various types of solid fuels. Duration determinedUHF-impact and distribution of temperatures on the fuelsurface, depending on its moisture content and fraction. It is proposed to use a pre-combustion device to increase the energy characteristics of fuel with a high moisture content (up to 80%) by combined heating of an electromagnetic fieldUHFand convective thermal - flue gases, as well as a condensing air heater. The results of the pre-combustion device usefor combined heating are: an increase in the drying solid fuelefficiency, an increase in its combustionheat. Homogenized fuel was obtained from low-grade cheap solid fuel with a high moisture content (wood waste), which in its energy characteristics is not inferior to expensive pellets. The joint work of the developed pre-furnace design and the condensing air heater allows: to determine the efficiency factor of a boiler plant, reduce fuel consumption, involve wood waste and low-calorie fuel with a high moisture content (up to 80%) in the fuel balance of boiler houses, recycle and reuse the heat of flue gases, reduce the concentration of corrosive substances in flue gases and condensate, which allows use it as make-up and process water.

There are most of the energy`s costs are accounted for by heating and hot water supply in communal housing conditions. Every day there is a growing need for the development and development of alternative options for energy generation technology. In the field of alternative energy, the most popular solution is a heat supply system based on air heat pumps (HP). Construction and installation work is simplified for integrated heat pump systems, but the question of the organization of design for these devices remains not fully resolved. The purpose of the work is to study the features and patterns of design and construction works with heat pump systems built into the premises in the field of low-rise construction and to develop measures to reduce the time and cost of such works. Heat engineering calculations for integrated heat pump systems that take into account climatic features, architectural and construction elements and parameters of engineering networks of the construction object, increase the complexity, cost and duration of design work. The research methods used are the analysis of the entire design process and in particular the section “heating and ventilation”, further modeling through network planning of the design process and comparison of the obtained data. The results of the study are calendar schedules of the design process of integrated heat pump systems on the example of a cottage structure with an area of 150 m2. For further analysis, the parameters of the time reserves of the working processes of the obtained network graphs are calculated. The section of heating, ventilation and heat supply (S) for integrated heat pump systems of heat supply is compared with the classical one, where the heat generator is an electric boiler. As a result of the study, a scheme for organizing design work is proposed, which allows you to plan the design of the section S without affecting the overall terms of execution of project documentation and the growth of its cost.

The paper presents the method of heat calculation of recovery stages for the plant of moisture evaporation from oil sludge. It enables to increase the plant power and reduce fuel consumption per one unit of evaporated moisture in heating boiler.

The result of the implementation of technical solutions should be evaluated in terms of the effect on the power system as a whole. At the same time, the main task is to obtain a socio-economic effect noticeable for the consumer of energy resources, as he is a key figure of the energy system. The article considers the influence of modernization of hot water supply systems (HWS) by transferring the function of hot water preparation in apartment buildings to individual heating stations (IHS) from the district heating stations (DHS) with their subsequent liquidation, as well as the elimination of hot water supply grid. The expected result of these measures is the reduction in heat energy loss in heat carrier agents in heating networks, as well as improving the quality and reliability of the hot water supply system and the possible reduction of energy consumption by residents in apartment buildings. The effect on the operation of the heat supply system will not be provided by IHSs themselves, but by automatic controllers, installed together with them. This, in turn, will make it possible for the Central Heating and Power plants (boiler) to be modernized in operation in a timely manner, to improve the system’s efficiency. Computational studies were carried out in order to assess the impact of the transition from IHS to hot water supply on the energy system.

In this paper, the authors determine the energy consumption for heating and air conditioning of an administrative building located in the second climatic area, in Romania. The heating and cooling system is provided with fan coils, and the fresh air is supplied by an AHU. The aim is to identify the best solution from 3 proposed heating and cooling systems that can be applied in order to improve the living conditions, namely: boiler with solid fuel (wood) or gas and chiller with mechanical vapor compression (VCM); reversible heat pump; boiler with solid fuel (wood) or gas and absorption chiller type LiBr-H2O driven by solar energy. The goal of the study is to select one of the three solutions which involves minimum investment and exploitation costs.

The aim of this research is to assess the construction of lowtemperature solid fuel boilers with special consideration of changes in their construction over the last years. The results contained in this paper are based on analysis of production program of 130 coal boilers manufacturers from Poland. Attributes which are the main subject of comparison and their classify with reference to compatibility with standards requirements consists with parameters indicating energetic properties of construction such as fuel consumption, heating surface, thermal load of heating surface, boiler efficiency, boiler mass, water capacity, slow-burning, and others. Results are compiled in tables and figures which allows comparing to compare construction features boilers in the same standard class. The main reason for this analysis is to show the direction of boiler industry evolution. These results can be used as construction data for new boilers, or to evaluate already existing boiler.

The article is devoted to the analysis of the technological process of heat load control and cost-effective fuel combustion in furnaces of drum steam generators at a thermal power plant. The object of automation – boiler unit type “Е-75-3,9-440G” – is analyzed. The mathematical model of fuel and air supply system to the steam generator is developed according to installed equipment characteristics. The model’s parameters are calculated. The actuating element of the system is an electric single-turn mechanism designed to actuate shut-off and control valves in the fuel and air supply channels. Two-channel control system is synthetized for providing an optimal ratio of fuel and air consumption with oxygen content correction in the flue gases. The automatic control system model is realized in Matlab application package, Simulink programming environment. The achieved results show the right settings for cascade control system. In conclusion, an example of the necessary technical equipment complex is listed for technical implementation of the developed control system.

The empty fruit bunches have remarkable potential for utilisation as solid fuel boilers in the production of energy. A well operated boiler with higher efficiency is vital for a good power generation plant. However, there are numerous safety and technical issues that may lead to a lower energy production rate. A simple yet complete probabilistic risk analysis is needed to predict those issues to ensure the biomass boiler operates at its maximum efficiency. In this work, a probabilistic risk assessment model for empty fruit bunch boiler using Bayesian network approach was developed. Bayesian network provides a clear probabilistic model of cause-effect relationships of the biomass boiler system. The conditional probability values were elicitated from experts’ opinion to identify the most influential factors for efficient biomass boiler operation. A case study from Renewable Energy Plant in Pahang was applied. Prediction analysis and diagnostic analysis were performed and the results show that the most important biomass boiler failure factors are corrosion and overheating. These findings are in agreement with existing literature and expert judgement. Thus, the proposed model is useful in maintaining and helping the decision maker for biomass boiler operation as well as increasing its reliability.

In order to solve the problem of low biogas production caused by low temperature in northern cold area, the solar energy and biogas boiler combination warming system is proposed to raise the temperature of biogas digester. In this paper, under the condition of the optimum area of solar collector, it's obtained that changeable rule of solar energy guarantee rate with month and rule of heating ratio of biogas boiler in the whole year. The solar energy guarantee rate of the system is more than 55.9%, and the combined heating capacity of solar energy and biogas boiler is enough to meet the requirements of annual operation conditions, which is reliable in the northern cold area.

To predict the boiler’s combustion efficiency and NOx emissions, this paper introduced a particle swarm optimization optimized XGBoost algorithm. The results show that the MAPE can reach 0.107% and 3.732% respectively on the verification set, which is better SVM, LR and ANN. At the same time, this paper presents a comprehensive benefits evaluation function considering economic and environmental benefits to optimize the multi-objective optimization problem of boiler’s combustion efficiency and NOx emission. Based on the operation data of a 300 MW Circulating Fluidized Bed, the experimental results show that: the comprehensive benefits evaluation function can reasonably balance boiler’s combustion efficiency and NOx emissions to achieve the optimal comprehensive benefit.

The aim of the study was to compere the effects of using air energy heat pump, flue heating and water heating as brood heating system on brood production of yellow-feathered broilers. In the experiment, three heating methods were used to heat chicks, and the parameters such as heating time, temperature uniformity, concentration of poisonous and harmful gases in the house, chick weight gain, mortality rate and production benefit were compered and analyzed. The results showed as follows: 1. There was no significant difference in NH3 and H2S concentration among the three groups (P > 0.05). The CO2 concentration in the flue group was significantly higher than that in the other two groups (P < 0.01), and there was no significant difference in CO2 concentration between the other two groups (P >0.05). 2. The body weight of chickens in the flue group at 30 days of age was the lowest, which was significantly different from that in the other two groups (P < 0.01); The air energy heat pump group had significant difference with coal fired boiler group (P < 0.05), the uniformity and survival rate of flue group were the lowest, and the air energy heat pump group had the best; 3. The temperature rise of honeycomb flue was the slowest, the temperature distribution uniformity was the worst, and the cost was the highest; The heating rate of coal-fired boiler was faster than that of flue, and the temperature distribution uniformity was better, and the cost was lower. The heating rate of air energy heat pump was the fastest, and the temperature distribution uniformity was better, and the operating cost was the lowest. 4. The air energy heat pump group has higher investment in the early stage, better use effect, better production performance of brood, long service life and lower brood cost.

Combustion of pure avian waste is strongly affected by its humidity content. According to the results of composition analysis, the initial humidity reaches up to 50%, inhibiting direct combustion initiation and development. Drying of poultry waste is an alternative, but simple relatively long-term storage or thermal pre-processing, complicates the technological process of energy recovery and increases the associated costs. Co-combustion represents a promising solution to enrich the heating value of raw poultry manure. Experiments using biomass (in a mass fraction of up to 30%) led to positive results in terms of efficiency. It is highlighted that the process depends on the quality of the woody biomass used for the mixture, but also on its bulk density, which causes an accelerated diffusion of air and influences the burning speed. This paper presents the experimental investigations on the co-combustion of poultry manure and woody biomass, performed on a 55 kW pilot boiler equipped with a post-combustion grate. The focus of the analysis is on the influence of the biomass bulk density and its heating value on the co-combustion process. The results obtained favor the development of a technology that is easy to apply and has a reduced cost. The technology investigated here is suitable for onsite applications in poultry farms, enabling meeting the energy demand based on co-combustion of resulting poultry waste.

In this work, an integrated numerical model combining combustion and fluid heating was established for a 660 MW coal-fired boiler. To validate the accuracy of the developed model, related experiment was also conducted, and shows that the relative errors (REs) of several predicted parameters on both flue-gas side and water-steam side of the boiler are less than 7 %, which meets the requirement of analysis. The results indicate that the effect of SOFA tilt angle on gas temperature deviation (GTD) is greatest, and that of SOFA’s proportion follows; while GTD presents a smallest sensitivity to the concentration of O2. This is because O2 concentration mainly affects the average value of the gas temperature, but barely changes its distribution. By contrast, altering SOFA’s tilt angle and its proportion directly varies the shape, location, and area of the high-temperature and low-temperature regions at the entrance profile of the horizontal crossover pass, so these two factors play a more important role in the variation of GTD.

The paper discusses challenges and a potential of fuel and energy savings in one of the republics of the North-Eastern region of the Russian Federation. The authors show the challenges of energyand heatsaving, with due account too particular features of Sakha Republic (Yakutia), which include: inconsistency of the actual operating conditions of the equipment with the requirements of regulatory documents in force; problems in supplying the consumers in the decentralized zone. The region’s goals in the segment of energy saving are determined. A detailed assessment of energy-saving potential in the electricity, thermal and fuel saving sectors is carried out. Energy saving is achieved mainly by reducing the losses in general-purpose utility networks, when switching to energy-saving lighting devices, as well as by reducing electricity consumption rate for water pumping, supply and sewage disposal. Heat energy savings can primarily be achieved only by reducing losses in heating services’ networks. Considerable fuel savings can be obtained by reducing the fuel consumption rate in boiler houses and diesel-run power plants. The results show high potential for energy savings in the region. Energyand fuel-intensive activities alone could save the estimated 1 million TOE every year.

The article analyzes the main advantages and disadvantages of centralized and decentralized heat supply systems in high-rise districts. The main schemes of centralized heat supply systems are considered. They include centralized heat supply from boiler houses, centralized heat supply from autonomous heat sources, heat supply from roof boiler houses and door-to-door heating supply. For each of these variant, the gas distribution systems are considered and analyzed. These systems vary depending on the heat source location. For each of these systems, technical and economic indicators are taken into account, the analysis of which allows choosing the best option for districts where high-rise buildings predominate.

The purpose of the article is to determine the profitability of investing in a graywater heat recovery system in a hotel facility located in south-eastern Poland whichis dependent on three heat sources for the domestic hot water preparation system, i.e. gas boiler, biomass boiler and electric heater. There were also various options for accommodation use: 25%, 50%, 75% and 100% occupancy of the hotel. The research was focused on the most frequently used methods for the absolute assessment of the effectiveness of investment projects enabling the creation of an objective criterion. Thus, both the simple method - Simple Pay Back Period SPBP and dynamic methods based on the discount account were used in calculations: Net Present Value NPV, Internal Rate of Return IRR, Profitability Index PI, Discounted Pay Back Period DPBP. The analysis also includes the annual increase in the purchase price of energy carriers. The conducted research has shown that in most cases the installation of the DWHR (Drain Water Heat Recovery) system is beneficial and profitable to the investor.

The aim of the work is to improve the energy efficiency of heating boiler plants by reducing the spe-cific electric energy consumption for heat supply by using the variable-frequency drive (VFD) with different methods of heat supply regulation. Hydraulic and thermal calculations of the heating net-work are performed on the example of the real district heating system. Heat network temperature charts of district heating are selected and calculated considering preservation of high quality of district heating. The description of the calculation algorithm of the research and the results of the calculation of the basic mode of district heating heat supply according to the standard temperature chart of varia-ble temperature control are given in the article. Places of installation of VFD are determined on the base of the basic mode. The results of calculation of three different methods of heat supply regulation are presented: standard heat network temperature chart of variable temperature control with using the VFD, extended heat network temperature chart of constant temperature/variable flow control, extend-ed heat network temperature chart using the VFD.

Stand-alone buildings operated periodically require heat supply for hot water and heating purposes to be carefully analyzed in terms of the technical capabilities, the energy and financial outlays. The paper presents the analysis of heat supply for hot water purposes and central heating in the stand-alone cloakroom building located in Poland. The analysis is undertaken for different variants of heat delivery for a building from electric heaters, gas boiler and district heating solutions to renewable sources applications, namely solar panels and heat pumps. For each solution, usage of usable, final and primary energy was calculated. Also the financial analysis for investments and energy costs were carried out. This analysis has been done in according to SPBT and NPV method for different levels of building use.

Analysis of a heat transfer process for construction of solid fuel heating boiler equipped with additional afterburning chamber is presented. Analyzed construction of the heating device is intended for shouse heating and preparation of hot utility water. A heat exchanger in the analyzed boiler is composed of vertical tubes divided into three boiler draughts. Afterburning chamber connects main combusting chamber of the heating boiler with second and third boiler draught. The aim of this analysis is to identify the character of heat transfer through the heating boiler

This paper discusses the use of modern and effective heating systems, using fossil fuels and renewable energy sources on the example of a comparative analysis of a gas boiler and heat pump for a single-family building. The aim of the work was to conduct a comparative analysis of heating systems in terms of energy, economy and ecology. The concepts of heating systems based on a gas boiler and a heat pump are proposed. An economic analysis based on the LCC and ecological method was carried out, related to the equivalent emission, in order to compare the degree of environmental nuisance of the proposed heat sources. For the building in question, a more advantageous solution was the use of a system based on a condensing gas boiler. The economic analysis shows that in the assumed life cycle (20 years), the total cost for a heating system based on a gas boiler is lower than in the case of a heat pump by 11%. Also, the initial costs in this variant are lower by nearly half compared to the heat pump system. Environmental analyzes have shown lower annual emissions of pollutants and a 6-fold lower equivalent emission for a gas-fired heating system.