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This paper outlines the prospect of obtaining water from atmospheric air by cooling it to the dew point temperature using refrigeration machines in order to partially reduce water scarcity in the arid regions of our planet. To minimize energy costs in the systems for obtaining water from atmospheric air, it is proposed to utilize solar energy with absorption refrigeration units (ARUs) acting as a source of artificial cold. The characteristic thermodynamic processes have been analyzed in a modernized ARU, capable of working at a lower thermal energy source's temperature than its analogs. The possibility has been studied to reduce the temperature of the heat source by including a solution vaporizer in the ARU scheme. The analysis involved an authentic method based on the balance of specific streams of ARU working body components and actual boundary conditions at characteristic points of the cycle. A limit was shown for the level of a minimum boiling temperature in the ARU generator (from 90 °C) when the systems for obtaining water from atmospheric air are operated under current climatic conditions. The simulation of heat-and-mass exchange processes during contact interaction between a steam-gas mixture and ammonia water solution was carried out. Based on variant calculations, it has been shown that the proposed ARU structure with an adiabatic solution vaporizer could work as part of systems to obtain water from atmospheric air at a hot spring temperature above 100 °C and constructively enough fits into the element base of standard models. It has been proposed to use two types of solar thermal energy sources to operate ARU. In a tropical climate, with vacuum solar collectors or solar energy hubs; in a temperate climate zone, with solar collectors with water as a heat carrier

This paper considers the processes of incineration, gasification, and slow pyrolysis. The common approach implies the use of individual models for the description of separate processes. When parameters acquire the values close to the boundary processes, the accuracy of description of the studied phenomena decreases. The specified processes do not have distinct boundaries between themselves and can smoothly transfer from one to another at changing external influences. While the physical and chemical processes are similar, the composition of the products of reactions, which are determined on the boundaries with the use of adjacent models, is different. In the most general form, the problems associated with incineration, gasification and slow pyrolysis are solved based on a unified model. The solution is complicated by the possibility of an unpredictable change in the composition of original substances. In addition, they can be located in various phase states: gaseous, liquid and solid. The previously developed system of equations that describes the process of combustion of organic fuel of unknown composition was taken as a basis for the unified model. The partial pressures of the products of reaction are the parameters of the model. In this approach, their condition is considered to be gaseous. The feature of the proposed unified model is the possibility of taking into account the condensed phase (coaly residue) of reaction products that is characteristic of slow pyrolysis. For a unified model, which describes the processes of incineration, gasification and pyrolysis, the calculation processes have differences. When studying the gasification and incineration processes, the temperature of the products of reaction is determined based on the equality of their enthalpy and the enthalpy of resulting substances. When studying the process of pyrolysis, the temperature of reactions and, respectively, of its products, is assigned. The found composition of the products and the assigned temperature allows calculating their enthalpy. The necessary amount of energy in the form of warmth to ensure the reaction of pyrolysis can be calculated based on the difference between the found enthalpy and the enthalpy of resulting substances. To prove the adequacy of the model, the calculations of cases of incineration and gasification of gaseous (methane), liquid (ethyl alcohol) and solid (pine wood) substances were conducted. The calculation of slow pyrolysis was performed for pine wood. Coincidence of the results with the data available in literature proved the relative errors admissible for engineering calculations. Based on the joint use of the model and previously developed method for determining the composition of gases mixture in the process of its incineration, the method of identification of the composition of hydrocarbon compounds of combustible substances in different aggregate states in real time mode was proposed.

The problem of improving the accuracy in the calculations of technical energy losses in the overhead transmission lines of voltage 6–35 kV was examined by taking into account climatic factors. The influence of climatic factors on the losses of electricity in the overhead transmission lines of voltage 6–35 kV was explored. We improved the model of thermal processes in the PTL wires through a fuller account of meteofactors. The approaches to calculating the losses of active power in PTL were analyzed and examined. We substantiated expediency of applying the approach in which the losses are calculated taking into account the average monthly air temperature. It was investigated, calculated and proposed to include, in the basic equation of thermal balance for the PTL wires, the heat transfer coefficients that take into account the impact of precipitation (rain, snow). We improved the basic equation of thermal balance for sustained thermal mode for the PTL wires with regard to the proposed approach to the selection of temperature and calculated heat transfer coefficients at atmospheric precipitation on the surface of the wires. The expression is proposed for determining technical energy losses in the overhead PTL of voltage 6–35 kV. We designed a model of neural network for forecasting and calculating technical energy losses in the overhead power transmission lines of voltage 6–35 kV, which has advantages in comparison with traditional models and will make it possible to reduce error when calculating and forecasting load electric power losses in PTL. Results of the study may be useful for forecasting and calculation of energy losses in the overhead PTL of voltage 6–35 kV in power supply and designing organizations.

The study focuses on the principle of water purification by electromagnetic focusing of the charged particles of contaminants. We have designed an electromagnetic control device (EMCD) of water treatment. A water flow is treated in an axially symmetric electromagnetic field. Aggressiveness of the filtrate is reduced due to a multi­stage process. The first stage involves the selection of the most aggressive components of the filtrate. The second stage is the choice of the physical impact on the flow of contaminants for their subsequent removal. The effect of the axially symmetric electromagnetic field on the charged particles of impurities provides the Larmor precession of the magnetic moment. The precession makes the impurity ions rotate around the vector of the external magnetic field. This spins the trajectory of the charged particles, whose total mass forms a paraboloid of revolution. The filtrate treatment involves focusing contaminants and removing them from the general flow. This allows controlling the mechanical trajectory of impurities when the latter are removed from the main flow. We have found the inverse relationship of the Larmor radius of the impurities and the focusing coil current. The value of the Larmor radius of impurities of 0.07 m is obtained by increasing the focusing coil current up to 0.1 A.

In regions with a continental climate, refrigerators with air-cooled condensers operate at high condensation pressures during the summer season which reduces their efficiency and accelerates the wear of compressors. To reduce condensation pressure, it was proposed to use radiative cooling which is a way of heat removal through the planet's atmosphere to outer space in a form of infrared radiation. A refrigerating machine with an assembly of condensation heat removal including air and liquid cooling condensers connected in series has been developed. To reduce the condensation temperature, a pre-cooled heat-transfer agent is fed to the liquid cooling condenser during the day hours at high atmospheric temperatures. At night, the heat-transfer agent is cooled by radiative cooling. An experimental study of the operation of a 600 W refrigerating machine including a sealed piston compressor was conducted. R134a refrigerant was used. Supply of pre-cooled heat-transfer agent at +33.1 °С has provided a reduction of condensation temperature from +47.0 to +39.1 °С. The study was conducted at an atmospheric air temperature of +38.0 °С. The degree of pressure growth was decreased by 30 %. The refrigeration coefficient was increased by 11 %. In comparison with the conventional scheme with an air-cooled condenser, energy consumption by the system did not change in the daytime. The offered scheme of condensation heat removal reduces the pressure of condensation and provides stability for refrigerating machine operation. It can be used in stationary refrigerating machines at high daytime temperatures.

Our study, aimed at assessing the impact exerted by the inclusion to a low-efficiency cyclone of an additional "bypass" pipe connecting the cyclone's inlet branch pipe and the exhaust pipe, has been established the mechanisms to improve the energy efficiency and the process of purifying air from dust. It has been proven that the increase in the degree of purification is explained by a decrease in the radial flow rate under the exhaust pipe of the cyclone. The decrease in hydraulic resistance is due to a decrease in the flow rate along the inlet branch pipe when the air is fed separately to the body through the inlet branch pipe and the "bypass" pipe. Our experimental study has confirmed that when the cyclone design is supplemented with a "bypass" pipe in the most dangerous area of the cyclone in terms of dust release (under the exhaust pipe), the radial rate of the gas flow that negatively affects purification is reduced. This leads to an increase in the overall degree of purification from dust. The result of analytical calculations and computer simulation by the SolidWorks-2009 software were experimentally confirmed when investigating the effectiveness of dust capture from powdered skimmed milk in an industrial cyclone (a 630-mm diameter) with a "bypass" pipe. Such a cyclone is installed in the system of pneumatical transportation at the spray dryer "CT-500" at Ichnya Milk Powder and Butter Plant (Ukraine). Specifically, it has been established that the removal of dust is reduced almost twice, hydraulic resistance ‒ by 15 %, and the energy efficiency of the cyclone with a "bypass" pipe increases by 2.43 times. Thus, there is a reason to argue about the possibility of significant energy efficiency improvement of the cyclone with a "bypass" pipe. This makes it possible to assess the energy efficiency of the cyclone in the early stages of design

Energy consumption is the most important strategy for improving economic efficiency and decarbonization. State energy saving measures aimed at promoting changes in sustainable habits and procedures can significantly save energy consumption. Information support for promoting the economic benefits of energy saving under the conditions of military conflicts needs more attention. The leading methodological tools were the methods of observation, comparison, as well as historical method. The research reported here showed that the aggression on the part of the Russian Federation required states to urgently improve the system of implementation of national information policies in order to increase the level of energy saving and energy efficiency. The EU's plans to reduce energy consumption "Play your role" and "Save energy" are aimed at informing the public about the need to contribute to energy saving processes. It is proved that currently in the EU, 80 % of member states ensure the effective implementation of new state campaigns for information support to promote the economic benefits of energy saving. Awareness-raising campaigns such as EPAH, I Have Influence, Green Ambassadors, EU4Energy's energy awareness campaign in collaboration with EU NEIGHBORS east are noteworthy. This activity and the set of energy labeling measures ENERGY STAR and EPREL can become the basis for the implementation of public education programs at educational institutions during the period of military instability in Ukraine. A promising vector of further scientific research will be the analysis of the practice of implementing information support to popularize the economic benefits of energy saving on the territory of Ukraine during the aggravation of the military conflict on the territory of the state

As a result of the research, the relationship between the ecological condition of the urban environment and fluctuating changes in the foliage asymmetry of trees, most common in the study area was revealed. The most appropriate urban air pollution indicator plants in accordance with the bioindicative sensitivity set of tree crops were identified. The dependence between the ecological condition of the urban environment and fluctuating changes in foliage asymmetry of trees, most common in the study area was found. The maximum asymmetry index of white birch was observed in the north-eastern pilot section, which is caused by emissions from the chemical industry. This allows to trace the trend of the environmental quality transition from the "pre-critical" condition to "critical". The integral asymmetry index of the leaf blade for areas with different anthropogenic impact levels under a changing industrial infrastructure of the city was designed. Within three years, the integral index increased (in 2012 - 0,048; 2013 - 0,058; 2014 - 0,059). To view the distribution of toxic substances in the city, the study of pH values of bark of trees, related in their properties to the species with a poor bark, which showed that there is a rise in the tree bark pH in most of the study city area was conducted. The resulting data of bioindicative research will allow to develop a number of administrative decisions and measures to reduce the value of the environmental risk indicator with increasing anthropogenic impact.