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The analysis of scientific works shows that the development of technology is ahead of the level of development of energy management. There are no clear comparisons of the energy efficiency of electrical technologies and heat technologies. Objective indicators of energy efficiency in various technologies of dehydration of raw materials not developed yet. In that article assumed that objective results for comparing energy efficiency in the processing of raw materials is obtained by the basis of system analysis of the entire energy conversion chain from fuel to finished product. The purpose of the work is experimentally proving the objectivity of this hypothesis. To achieve this goal, it is proposing to use the indicator of the energy share of fuel in the finished product and the amount of moisture removed when burning 1 kg of fuel, which does not depend on fluctuations in energy prices, which can vary and differ for different countries. The most important result of the work is the comparison of these parameters with the data for innovative equipment samples developed by the authors. The significance of the results obtained is that the evaporating devices developed by the authors are not inferior in efficiency to traditional ones, and make it possible to obtain concentrates up to 90 ° brix. Thus, for fuels with an oil equivalent of 40 MJ per 1 kg, traditional dryers can remove no more than 3 kg of moisture, cryoconcentrators – 20 kg.

The article considers mathematical approach to environmental quality management to improve the ecological comfort of living for the population. The problem of environmental management is described using a multi-factor model of quality of the environment with the weight coefficients of the importance of its components: atmospheric air, acoustic impact, soil, water resources, and green spaces, accessibility of natural and recreational areas. The values of weight coefficients of importance of influencing factors for environmentally comfortable living are determined by the method of expert assessment. A multi-factor model is used for detailed assessment of the ecological quality of the urban environment. The proposed quantitative approach also allows to compare the environmental comfort of the different residential districts or to study the dynamics of environmental comfort of specific urban area. Much attention is paid to scientific and methodological principles of management and the formation of the concept of «environmental quality». The strategy of environmental management with ecological foundation of various practical solution is shown. The plan of measures on organization of optimal management of quality of the environment to improve comfort of living for the population of the residential microdistrict of Tiraspol is presented. Graphical scheme of the results of integral analysis of various environmental indicators and assessments for improving the comfort of the environment is given. Realization of environmental quality management of the urban areas on the basis of a multi-factor model contributes to the gradual change of dangerous ecological conditions of environmental factors, to increase a comfort of the territory taking into account the real preferences and needs of the population.

A significant number of domestic and industrial boilers are in operation in Ukraine. Nitrogen oxides are the most dangerous among all combustion products that pollute the atmosphere, therefore, one should take some measures for decreasing the formation of nitrogen oxides during combustion. The studies were carried out at the boilers of low power (100 kW) with a tubular radiator and an open end. The studies in the furnaces of industrial steam boilers having a tubular radiator with a closed end have not been done. The numerical study results of the gaseous fuel combustion processes in the furnace of a DE-10/14 steam water-tube boiler are presented. The fuel-air mixture is formed by premixing the 15% part of the air with a primary burner twist factor n=2.4 and a secondary burner twist factor n=1.6, and an air excess factor αв=10. As a result of the studies, the temperature and velocity distributions of gases in the combustion chamber, the density of heat flows on the screen tubular surfaces, and the concentrations of the combustion components were determined. Flue gas recirculation in the volume of 80-100% is provided, and the reversible movement of combustion products towards the combustion front provides a reduction in the concentration of nitrogen oxides up to 123-125 mg/m3 at the furnace outlet. Disadvantages are the following: the formation of stagnant zones near the end of the secondary radiator. The optimum diameter of the tubular radiator equals to two burners diameters and tubular radiator is located at a distance of one meter from the burner cutoff.

The issues of improving the efficiency of methanol usage as a promising marine power plant fuel with low carbon content are discussed. The main aim of the research is an analysis of characteristics of advanced marine gas turbine power plants with the combined thermodynamic and thermochemical regeneration of waste heat. The possible methanol conversion at the expense thermochemical heat regeneration of marine engines recoverable resources has been revealed. The analysis of parameters influences of the waste heat recoverable resources, as well as restrictions related to the engine system of gas fuel injection, on the efficiency of methanol conversion has been carried out. It was demonstrated that the simulation of methanol steam conversion processes results in the pressure increase in the reactor, which, in its turn, causes a shift of conversion efficiency process towards higher temperature area. The calculation scheme of steam injection gas turbine plant with the joint thermodynamic and thermochemical regeneration of waste heat is demonstrated. The results of mathematical simulation of the processes in regeneration plant under the 3.4 MW constant capacity and heat exchanger thermal ratio of 0.85 were obtained. The cycle optimization has been based on the efficiency of plant under the conditions of variation of water/methanol ratio and gas temperatures in thermochemical regenerator. The efficiency increase constituted 4% relative to characteristics of the base engine operating on methanol. The estimation of carbon content in produced syngas has shown that thermochemical regeneration of methanol conversion by using the waste heat can reduce the energy efficiency by 1.5 times.

The use of low-grade gases in the fuel and energy balance of enterprises makes it possible to increase the energy efficiency of technological processes. The volumes of low-grade gases (blast furnace and coke oven gases, synthesis gas of coal gasification processes, biogas, coal gas, etc.) that are utilized more significant in technological processes but their calorific value are low. At the same time artificial gases contain ballast gaseous (СО2, H2O) and mechanical impurities that are harmful gas impurities. Their use requires technological preparation. Thus coal methane is characterized of high humidity, coal dust and drip moisture, variable composition. Thus was effective burning of coal methane it is required the development of constructive and regime measures that ensure a stable and complete burning of gaseous fuels. In this article it is presented the results of computer simulation of a stationary turbulent diffusion flame in a restricted space in the process of burning natural gas and coal methane in a bottom burner. The calculation results contain the fields of gear, temperature, concentration of CH4‚ CO‚ H2O‚ CO2 and nitrogen oxides. The structural elements of the flame (recirculation zone, hot "dome", mixing layer and far trace) are determined. It has been established that complete combustion of coal methane in a modified bottom burner is ensured and the numerical values of nitrogen oxide concentrations in the flame are consistent with the literature data.

Ukraine in terms of water availability ranked 17th among 20 European countries. Its water resources depend on the river flow from the territories of the neighboring countries (76.6%) and only about a fourth of it is formed within the country (23.4%). The prevailing part of the territory of the country is characterized by low and very low water availability (1.98 - 0.12 thousand m3 per person). Only the Transcarpathian region belongs to the category of average water availability (6.3 thousand m3 per person.) Most of the research results confirm the high probability of a 25-70% decrease in the water resources of the Ukraine in the 21st century. Stabilization and even an increase in water resources are expected within the Ukrainian Carpathians. Given the results of modeling, we should expect further increase in the water deficit in the zone of unsustainable agriculture - in the southern regions of Ukraine already to the middle XXI century. Украина по показателю обеспеченности водными ресурсами занимает 17 место среди 20 европейских стран. Ее водные ресурсы зависят от речного стока с территорий прилегающих стран (76,6%) и только приблизительно их четвертая часть формируется в пределах страны (23,4%). Преобладающая часть территории страны характеризуется низкой и очень низкой водообеспеченностью (1,98 - 0,12 тыс.м3 на одного человека). Лишь Закарпатская область принадлежит к категории средней обеспеченности местным стоком (6,3 тыс.м3 на одного человека. Большинство результатов исследований подтверждают высокую вероятность уменьшения водных ресурсов равнинной Украины в ХХІ веке на 25-70%. В пределах Украинских Карпат ожидается стабилизация и даже увеличение водных ресурсов. Учитывая имеющиеся результаты моделирования, следует ожидать дальнейшего увеличения дефицита водных ресурсов в зоне неустойчивого земледелия – в южных регионах Украины уже к средине ХХІ века.

The current state of the macrozoobenthos in the pseudolittoral zone of the Kazachya Bay was studied and a comparative analysis of its qualitative composition and quantitative indicators was carried out in different periods and seasons of the research. In 2007–2010 and 2021–2022, 86 macrozoobenthos species from different taxa: Polychaeta (36 species), Crustacea (33), Mollusca (13), Platyhelminthes, Oligochaeta, Chironomidae and Nemertea were found. By 2022, their number increased by 1.6 times. Moreover, 38 species of hydrobionts were added to the list. Fourteen species of macrozoobenthos were identified only in 2007–2010. Average values of abundance and biomass of macrozoobenthos in 2007–2010 varied from 774±176 to 4051±306 ind./m2 and from 0.585±0.216 to 12.57±0.033 g/m2, respectively. In 2021- 2022, they varied from 24±17 to 7352±3514 individuals/m2 and from 0.021±0.016 to 18.945±11.557 g/m2, respectively. In both periods, maximum abundance of macrozoobenthos formed by Polychaeta was registered in summer. In 2007–2010, the maximum biomass of macrozoobenthos was registered in summer, and in 2021–2022 it was observed in autumn. Mollusks made a significant contribution to this indicator in both periods. The trophic structure of macrozoobenthos is represented by polyphages, phytophages, detritophages and carnivores. In 2007–2010, oligochaetes were registered in 43 % of the samples in winter; H. acuta (Draparnaud, 1805), which belongs to plant detritivores, was the dominanhe species from April to September. In 2021–2022, the largest number of mass species was registered in the autumn-winter period, and S. papillocercus Bobretzky, 1872 dominated there. In spring and summer, polychaetes Capitella capitata (Fabricius, 1780), Salvatoria clavate (Claparиde, 1863), Microphthalmus fragilis Bobretzky, 1870 and amphipod Pectenogammarus foxi (Schellenberg, 1928) - representatives of polyphagous and phytophagous species - dominated in terms of occurrence. Changes in the number and taxonomic diversity of mass species with different feeding types in different seasons can be associated with the breeding season of hydrobionts and changes in the food supply. 

The purpose of the research is to determine criteria and calculate optimal ratio of different renewable energy sources (RES) for hybrid systems, estimate the random component of power fluctuation and consider the opportunities for its minimization. As a subject of the study it is variable and poorly forecasted in a short-term prospect character of generated power can negatively affect modes of grid operation. This concerns stability of dynamic processes in the systems of power supply. To develop a mathematical model of these processes a number of factual data on the climatic parameters and energy consumption regimes during the joint operation of solar and wind stations was used. As an experimental study suggests, the initial data were collected and statistically processed. Based on the results, mathematical models were developed in the form of a composition of deterministic and stochastic components and theoretical studies on the search for optimal ratios of capacities of wind and solar power stations were carried out. The object of optimization in the work is the load variability. As a combined single criterion, it was proposed to use the coefficient of variation. The ratios of the wind and solar components of the power generation, considered in this study, has allowed us to determine variants with a minimal dispersion of RES generation or with a minimum ratio of dispersion to average generated power which depends on the average annual or seasonal weather conditions. As a rule, the share of wind power plants should be 10-40% of the total rated RES power, depending on the total share of RES.