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V.1(49), 2022
95-102The problem of increasing energy saving when using fuel in heating furnaces of forging and thermal shops for heat treatment of metal under pressure treatment (forging and stamping) and heat treatment (quenching, tempering, carburizing and nitrocarburizing) is considered. Ways to improve energy saving in industrial furnaces and issues of reducing fuel consumption in thermal processes were studied. The problem of rationalizing the regeneration of low-grade heat of flue gases was not solved fully enough, since economic factors and the influence of the determining parameters on the temperature and thermal regimes of heat recovery plants were not fully taken into account. Thus, it is relevant to address the issue of the appropriate degree of recovery of the thermal potential of the gases leaving the heating furnace, finding the most favorable parameters of heat recovery plants. A criterion is proposed for assessing the effective level of the degree of utilization of the heat of exhaust gases at the outlet from the heating furnaces. It is proposed to evaluate the efficiency of the heat recovery plant and determine the optimal degree of heat recovery from flue gases leaving the heating furnace based on the difference in the changing costs for the construction and operation of the heat recovery plant. A method and an algorithm for determining the technically and economically feasible degree of utilization of low-potential heat of fuel combustion products after furnace units in a heat recovery unit have been developed. The developed algorithm provided the necessary optimality conditions, was checked for sufficiency by conducting studies on the existence of an extremum at the test point and the positivity of subsequent derivatives. The dependences of the economically viable temperature of the fuel combustion products after the heat recovery plant on the determining factors, basic values, price indicators and initial data are obtained, which, in the case of reconstruction and modernization of the furnace facilities of forge and thermal shops, minimize the costs of reconstruction and increase the efficiency of its use. The practical significance of the application of the proposed developments for practical use in the design, reconstruction and modernization of the furnace facilities of forging and thermal shops has been substantiated. -
V.1(49), 2022
103-110The article deals with the issues of joint use of a low-temperature solar collector and a heat pump in a solar heating system, the combination of which allows for high energy efficiency and stable operation of the system for the entire period of the year. The study and development of innovative technologies in alternative energy is a topical issue of today. Based on the actual statistical climatic data of the city of Omsk, a thermal calculation of the solar collector and the air heat pump in the heat supply system of the building was made. The values of solar insolation and the angle of inclination for the city of Omsk by months determined depending on latitude are given, the dependence of the change in solar insolation of the city of Omsk on the period of the year is plotted. The proposed scheme allows creating high energy efficiency and stable operation of the system during the summer and transitional months of the year. A method for calculating the generation of thermal energy using a combined system is given. The required number of tubes of solar vacuum tubular collector SVK-20A has been calculated. The work of an air heat pump and a solar collector according to a bivalent scheme is proposed, and a graph of the heat load of the heating system is also considered. The thermophysical properties of the working substance of a solar collector and an air heat pump are studied with a change in ambient temperature, the dependence of the freezing point of aqueous solutions of ethylene glycol and propylene glycol on the mass concentration of glycol is studied. A technical calculation of the COP coefficient for one of the educational buildings of OSTU was made. An effective option for using this system is proposed - heating systems «warm floor», «warm walls» or «warm ceiling». -
V.2(46), 2021
115-124In the article, on the basis of the thermodynamic analysis of the working process in the turbine, a method is presented for determining the generation of electricity based on heat consumption and an assumption is made about the possibility of instrumental measurement of the amount of generation and the implementation of accounting in real operating conditions of the steam turbine. This indicator can become an important indicator in the district heating system and automatic regulation of heat energy supply, such a statement of the problem in the district heating system was made for the first time and requires additional research. The article discusses the influence of electricity generation on thermal consumption on the efficiency of the power system of district heating. Dependences of electricity generation based on heat consumption on the share of steam supplied to the heating extraction are obtained. Specific power generation has been determined taking into account regeneration. -
V.4(40), 2019
120-128In article the technological actions for suppression of formation of harmful emissions from power objects using organic fuel are described - natural gas, coal and fuel oil. The methods of purification of combustion gases of the main pollutants are offered. Devices of cleaning of large volume of combustion gases of the increased concentration of ashes, and technology of combustion of fuel are presented. -
V.1(45), 2021
133-141The article deals with the application and use of heat pump installations as a low-potential source of heat energy to provide consumers with heat energy in the building heating system. Today, one of the most environmentally friendly and economical alternative sources of thermal energy is a heat pump unit. The use of these devices will reduce COemissions. The main advantages and disadvantages that appear during the operation of heat pumps are listed. Based on the results of tests of boilers using organic fuels (coal, fuel oil, natural gas)and low-potential heat sources with an electric drive, the dependences of the heat transformation coefficient of the heat pump and the efficiency of boilers operating on organic fuels on the cost of conventional fuel per unit of released energy are constructed. The coefficient of heat transformation of heat pump installations in the range of changes in operating parameters 3,0 < µ < 5,0 is determined. A graph of the dependence of the energy conversion coefficient on the temperature of the heat carrier in the heating system and the ambient temperature is constructed. A schematic diagram of the connection of a heat pump installation to the building heating system is proposed. Studies were conducted in the period from April 1 to April 21, 2021 in the laboratory auditorium of the educational building of OmGUPSa and the readings of the main parameters of the operation of the heat pump unit with the Vitocal 242-S heat pump were recorded. Based on the results of the main parameters, the following are calculated: the thermal load on the room heating system; the temperature of the coolant in the supply pipeline; the amount of electricity consumed by the heat pump; the conversion coefficient of the COР. The optimal values for this heat pump unit under the specified operating modes are estimated. -
V.1(41), 2020
133-140The calculation of the forecast demand for electric energy by energy systems and complexes of the constituent entities of the Russian Federation is an urgent task. The use of deterministic methods for objects of a similar scale is practically excluded due to the absence or significant incompleteness of the source data. Statistical data available in official sources in an unchanged format is usually presented for a period of 3 - 5 years, which is insufficient for the use of artificial neural networks. The article attempts to study the properties of similar energy systems and complexes. Modern power systems and complexes belong to closed subsystems, the set of elements and connections of which is equivalent to the set of elements of local subsystems of a higher level energy system. This means the inadmissibility of drawing up predictive rules of functioning without taking into account heterogeneous external influences. The system and subsystems are presented as a "black box". Interactions between the system and the external environment and within the system are carried out by the transmission of signals, which are described by a finite set of factors available for analysis and forecasting. The analysis of the possibility of supplementing the general population with statistical data on other objects with a similar structure is carried out. The property of heteromorphism of energy systems and complexes is confirmed. The example of energy systems in the regions of the Russian Federation shows the possibility of a similar approach if non-collinear groups of factors are applied to the analysis. The results of 15 calculations of the most energy-intensive entities of the country are presented, in 28 % of cases the accuracy of forecasted power consumption accuracy is less than 5 %. A further increase in the accuracy of the forecast should develop in the direction of increasing the number of input factors, subject to the condition of the absence of their collinearity and multicollinearity. It is shown that energy systems and complexes of various scales can be described by non-Gaussian stable distributions with infinite dispersion of non-Gaussian distributions, which makes incorrect the use of such methods as the simple extrapolation method, as well as statistical methods based on the assumption that the random distribution law is normal.