**HEAT-AND-POWER ENGINEERING FUNDAMENTALS**

* *

*Yu.A. Kirsanov ^{*}, A.E. Yudakhin^{*}, A.Yu. Kirsanov^{** }*

**REGENERATOR WITH THE POLIMERIC NOZZLE OF A**

**HEAT-VENTILATION SYSTEM**

**(**

*Transactions of Academenergo*. 2020. N 2. pp. 7-22).

**doi:10.34129/2070-4755-2020-59-2-7-22.**

^{*}*Institute of Power Engineering and Advanced Technologies, FRC Kazan Scientific Center, Russian Academy of Sciences, Kazan*

^{**}*Kazan National Research Technical University named after A.N. Tupolev – KAI «KNRTU–KAI», Kazan*

**Keywords:**heating-ventilation system, regenerative air heater, non-stationary processes, heat transfer, calculation, optimization.

**Abstract**

The article describes a heating-ventilation system (HVS) that utilizes heat energy obtained from air in a polluted room. A regenerative air heater (regenerator) is reviewed as the heat utilizer. The regenerator uses the plastic plates that have corrosion resistance in the mixture of air and natural gas combustion products at moderate temperatures. The method of thermal calculation of HVS and the mathematical model of the regenerator are presented. The results of calculating the system with the thermal power 10 kW (HVS-10) are obtained for the single and multi-sectional generator rotor. The method of choosing the number of sections and velocity of the generator rotor is presented.

**INDUSTRIAL HEAT-AND-POWER ENGINEERING**

*E.A. Lapteva, E.Yu. Stolyarova *

**REDUCING WATER COOLING WITH MINI COOLER 1**

**(**

*Transactions of Academenergo*. 2020. N 2. Pp. 23-30).

**Doi:10.34129/2070-4755-2020-59-2-23-30.**

**e-mail:**grivka100@mail.ru

*FSBEI of HE “Kazan State Energy University”, Kazan, Russia*

**Key words:**cooling tower, energy saving, energy consumption, recycled water.

**Abstract**

The use of a mini cooling tower with a rolled corrugated nozzle as a replacement for large-scale industrial cooling towers is considered. It is shown that mini cooling towers provide an increase in hydraulic load and cooling efficiency of circulating water. The theoretical basis of the study is a modified method of thermal transfer units, taking into account the back mixing of water and air in the cooling tower irrigation units. The object of research is the design of a mini cooling tower with highly effective regular roll nozzles, patented by the authors. The replacement of a large-scale cooling tower with a diameter of 20 meters (SK-400) with several mini-cooling towers with high specific loads and reduced energy consumption is considered. From the data of industrial operation and the calculations made, it follows that the SK-400 large-sized cooling tower is inefficient in comparison with a mini-cooling tower. Reduces energy costs for air supply using mini cooling towers by 40%. The advantages of using mini cooling towers with modern regular nozzles are shown

*A**.**V**. **Nuzhdin**, **N**.**Yu**. **Kurnakova**, **D**.**S**. **Katolichenko *

**INCREASE OF ENERGY EFFICIENCY OF VERTICAL STEAM HEATING HEATERS**

**(**

*Transactions of Academenergo*. 2020. N 2. Pp. 31-42).

**Doi:10.34129/2070-4755-2020-59-2-31-42.**

*M.I. Platov South-Russian State Polytechnic University (NPI)*

**Keywords:**heaters of network water, heat of condensate, increase of energy efficiency, reduction of steam consumption, saving of thermal energy.

**Abstract**

The energy characteristics of the existing boiler plant with PSV type heaters are calculated and the turbine power losses by months are determined by the selection of steam for the heaters. To improve the energy efficiency of the heaters, by reducing the steam consumption, the mode of their operation was modernized in order to use the heat of the condensate. Calculation of the boiler room after modernization under similar operating conditions showed a decrease in steam turbine power losses by an average of 2.2% per year. The annual energy savings in this case was 1433.29 GJ. The calculations were performed using standard methods of thermal calculation of recuperative heat exchangers [1, 2]. The performed calculations showed that without a costly intervention in the design of water heaters such as PSV, only a change in the mode of their operation can lead to a certain saving of thermal energy.

*M.M. Farakhov, E.A. Lapteva *

**EXPERIMENTAL STUDIES OF BINARY AND MULTICOMPONENT RECTIFICATION OF MIXTURES IN A COLUMN WITH NEW NOZZLES**

**(**

*Transactions of Academenergo*. 2020. N 2. Pp. 43-54).

**Doi:10.34129/2070-4755-2020-59-2-43-54.**

*FSBEI of HE “Kazan State Energy University”, Kazan, Russia*

**Key words:**distillation, contact tips, experiment, multi-component mixtures.

**Abstract**

The actual problem of experimental research of new contact devices of the nozzle type for rectification columns in chemical technology is considered. The presented results of experimental studies of separation of binary mixtures: acetone-water and ethanol-water, as well as a three-component mixture: methanol-ethanol-water in columns with regular and chaotic nozzles. A chaotic metal nozzle “Injekhim” was studied, which is made in the form of a hollow body of rotation, the surface of which is formed by thin strips of sheet material arranged one against the other, curved outwards. The specific surface area of the nozzle is 270 m

^{2}/ m

^{3 }with a nominal element size of 16 mm. the Regular roll nozzle has a corrugated surface in the form of ribbons that are twisted into a roll with a cross arrangement of corrugations. Also, the investigated nozzle is made of a thin mesh. For the study, a distillation column with an infinite phlegm number with a diameter of 0.098 meters and a height of the nozzle layer of 3 meters was used. The experiments were performed under the heat load of the rectification column boiler of 3 kW and 12 kW (steam speed from 0.4 to 1.5 m / s and irrigation density from 3.8 to 14 m

^{3 }/ m

^{2}h). The values of the pressure drop, temperature, and composition of mixtures for the column height are obtained. The experimental data were processed and generalized, and the values of the height of the equivalent theoretical dish (VETT) for the chaotic metal nozzle “Injekhim-2012”, regular corrugated metal tape and regular thin mesh were calculated. The results for the value of VETT at different steam rates and irrigation densities are presented. Experimental profiles of component concentrations by the height of the three-component mixture separation nozzle layer are given. Expressions for determining the efficiency of separation of multicomponent mixtures are presented in a General form, taking into account the superposition of the influence of components. The results obtained can be used in the design or modernization of rectification columns.

**POWER GENERATION STATIONS**

*A.A. Filimonova, N.D. Chichirova, A.A. Chichirov, A.I. Minibaev *

**PROSPECTS FOR USING OF ELECTROMEMBRANE TECHNOLOGIES IN POWER ENGINEERING**

**(**

*Transactions of Academenergo*. 2020. N 2. pp. 55-76).

**doi:10.34129/2070-4755-2020-59-2-55-76.**

*Kazan State Power Engineering University*

**Keywords:**electrodialysis, electro-membrane technology, thermal power plants.

**Abstact**

The review presents new and traditionally used at thermal power splant electro-membrane technologies, the main purpose of which is to control water-intensive industrial processes for recycling water and valuable products, as well as to reduce waste from the point of view of the “zero discharge” strategy. The main promising areas of the application of electromembrane technologies in the energy sector with a pilot industrial and industrial degree of implementation include demineralization of natural water by electrodialysis and reverse electrodialysis, the production of highly pure water by electrodionization, the disposal of highly mineralized wastewater from industrial enterprises by diffusion dialysis, the production of acids and alkalis from salt solutions using bipolar electrodialysis, electrochemical adjustment of the mineral composition of water in circulating systems and heating system, and others.

*V.E. Yurin, A.N. Egorov, A.B. Moskalenko, M.A. Murtazov *

**СOMPREHENSIVE INVESTIGATION METHODOLOGY OF THE EFFECTIVENESS OF WAYS TO PERFECT NUCLEAR POWER PLANTS, USING THE EXAMPLE OF A COMPARATIVE ANALYSIS OF AN AUTONOMOUS HYDROGEN ENERGY COMPLEX**

**(**

*Transactions of Academenergo*. 2020. N 2. pp. 77-96).

**doi:10.34129/2070-4755-2020-59-2-77-96.**

**e-mail:**sncransar@san.ru, urin1990777@bk.ru

*Saratov Scientific Center of the Russian Academy of Sciences*

**Keywords:**nuclear power plant, сomprehensive investigation methodology, multifunctional power generating unit, backup of auxiliary needs of nuclear power plants, core damage, autonomous hydrogen energy complex, blackout.

**Abstract**

Safety in modern nuclear power plants is based on the development of passive heat removal systems. The main disadvantages of these systems are: large investments, limited useful use of systems only in emergency situations with significant costs for maintaining them in ready to work condition, the dependence of the effectiveness of these systems on weather conditions. The authors offered a new point of view at the search of ways to ensure the safety of nuclear power plants, taking into account the factor of efficiency and operating conditions of nuclear power plants in energy systems with uneven energy consumption schedules. The method for the beneficial use of the residual heat energy of the VVER type reactors for autonomous power supply to consumers of nuclear power plants own needs, using an additional low-power steam turbine in emergency situations, accompanied by complete blackout, has been developed based on the experimental data of the Balakovo NPP. The regular operation of an additional steam turbine can be ensured by increasing the capacity of the reactors (during the construction of new power plants, the necessary power can be incorporated in the project), and by installing accumulation systems. These systems make it possible to generate additional steam during off-peak hours by accumulating energy during off-peak hours, which can be used to function an additional steam turbine. A new direction in the development of nuclear power plants requires the creation of a methodology that takes into account all significant factors, affecting the final efficiency of the developed multifunctional systems. The paper presents a method, developed by the authors, that allows ranking the ways to improve nuclear power plants based on a comprehensive analysis of the economic efficiency, safety and system effects, that are achieved when installing new and upgrading working equipment. As an example, the multifunctional system, developed by the authors on the basis of an autonomous hydrogen energy complex, and the known alternative options for the development of nuclear power plants are investigated.

**ECONOMICS, ECOLOGY, INNOVATIVE TECHNOLOGIES**

**AND PROCESSES IN POWER ENGINEERING**

*S.V. Panferov, V.I. Panferov *

**ON THE DETERMINATION OF THE AVERAGE TEMPERATURE OF INTERNAL AIR IN AUTOMATION OF HEATING SYSTEMS BUILDINGS**

**(**

*Transactions of Academenergo*. 2020. N 2. pp. 97-108).

**doi:10.34129/2070-4755-2020-59-2-97-108.**

**e-mail:**bk97@is74.ru, tgsiv@mail.ru

*South Ural State University, Chelyabinsk*

**Keywords:**automatic control, feedback, control of the average temperature of internal air, representative point, wireless sensor network, coolant flow rate, return water temperature, heating system.

**Abstract**

The problems of energy saving in the housing and communal sector and improving the quality of the microclimate of buildings are actual problems of the present. The solution to these problems is possible, first of all, due to the automation of heating systems. Therefore, consideration of issues related to the construction of high-quality automatic heating control systems is a very significant task. The problem of determining the temperature of the internal air to build a feedback channel in automation systems that implement a combined control principle is considered. The methods known in the literature for solving this problem are analyzed. It is indicated that neither the representative point (s) method, nor the multi-sensor methods, both wired and wireless networks, neither the physical model method, nor the temperature method in ventilation ducts can be considered as perfect enough to determine the average temperature of the building’s internal air. The problem requires further study and development. The essence of the proposed methods for determining this value lies in the fact that the return water temperature carries information about all the values that affect the heat consumption, including the temperature of the internal air, therefore, using the heat transfer model, we can estimate the return water temperature and internal air temperature. It is only necessary in this case that the heat transfer model is properly tuned to the experimental data (for a particular building). To implement one of the options, it is necessary to measure the mass flow rate of the coolant for the entire heating system, as well as the outdoor temperature, direct and return water. In another case, it is not necessary to measure the temperature of the outside air, since this takes into account slightly different ratios of real heat transfer. Both methods are based on a static (stationary) approach to the description of heat transfer processes. The admissibility of this technique is confirmed, in particular, by the stochastic approach, since the regression equation obtained from experimental data has a high value of the correlation coefficient. The results can be used in the design of modern building heating control systems.

**I.R. Hasanov, R. R. Rakhmatullin, I.N. Hamidullin **

**METHODOLOGY FOR DETERMINING EFFICIENCY OF INVESTMENTS FOR REPAIR AND RECONSTRUCTION OF MAIN FUNDS OF ELECTRIC NETWORKS. KEY PERFORMANCE INDICATORS**

**(**

*Transactions of Academenergo*. 2020. N 2. pp. 109-119).

**doi:10.34129/2070-4755-2020-59-2-109-119.**

*Network Company OJSC*

**Keywords:**efficiency, renewal of fixed assets, maintenance, repair, repair efficiency, determination of the amount of repair, ranking, planning, key performance indicators.

**Abstract**

This article addresses the issue of assessing the effectiveness of investments in assets of electric grid organizations. A technique is proposed for determining the most effective options for capital investments for repair and reconstruction of basic equipment based on the calculation of changes in the technical condition index and the necessary capital investments. The article also offers key performance indicators for the organization of the process of maintenance and repair.