• Energy Research
• other engineering and technologies close
• 6. Clean water close
• UA close

The paper presents the comparative analysis of the amount of waste generated in Ukraine and European countries (except for radioactive waste) based on the official EU and Ukrainian statistical data. The data on waste generation are compiled according to the following classification: by economic activity and household, waste category, grades of hazard, and regions. In Ukraine, 352.3 million tons of waste was generated in 2018. By 2018, almost 13 billion tons of waste had been accumulated at the managed dumpsites, including about 12 million tons of hazardous and over 200 million tons of household waste. In the European Union, 2.6 billion tons of waste was generated in 2018. Over 70% of it was generated by 10 countries: Germany, France, England, Poland, Romania, Italy, Sweden, the Netherlands, Spain and Finland. By economic activity, the largest amounts of waste in Ukraine are generated by the mineral extraction and processing industry, the smallest – from water treatment and construction. In the EU countries, these values are somewhat different. For example, in Germany and France, the largest amounts of waste are generated from construction and manufacturing, the smallest – from agriculture, forestry and fishery. By waste category, the waste generated both in the EU countries and in Ukraine is mineral and solid waste. In Ukraine, the largest amounts of waste are produced and accumulated in the Dnipropetrovsk, Donetsk and Zaporizhzhia regions which accommodate large enterprises for extraction and mineral processing of iron and manganese ores, titanium-zirconium placers, coal, dolomite, and metallurgical limestone, as well as metallurgical and ferroalloy plants.

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

The galvanic industry and the production of printed circuit boards are a significant source of environmental pollution, they pose a threat comparable to the chemical industry. They pollute both the atmosphere, the biosphere and the hydrosphere. The paper presents an assessment of the negative impact on the environment, galvanic production and the resulting post-production waste. It was proposed to use the technology of regeneration of used treating solutions, in which the recovered metal can be reused as a secondary raw material for the production of copper products. The regenerated solution, on the other hand, can be used to treat integrated circuit boards. As part of the work, with the use of a microscope, the structural characteristics of the metal surface obtained as a result of the applied regeneration process were carried out. The indicator of the total exposure to substances present in the deposit formed during production was determined, both before (0.045) and after the introduction of the new technology (100). The economic analysis of the planned project based on the new technology showed that the implementation of the presented method of wastewater treatment allows for obtaining significant benefits, both financial and environmental. The analyses performed can be a valuable source of information on how to reduce the impact environment during the production of integrated circuit boards, as well as on the possibilities of obtaining less expensive materials in the form of secondary raw materials.

AbstractThe article describes the process of deep aerobic mineralization of activated sludge in municipal wastewater treatment plants using a complex of aerobic heterotrophic and autotrophic microorganisms, including denitrifiers.

The process of dispersion of slaked lime in a vibrating activator of the bunker type is investigated. The nature of the change in the viscosity of lime dough during machining by vibration and rotary viscometer has been studied. It is established that the process of vibroactivation of hydrated lime successively goes through the stages of proportional growth of dynamic viscosity, slowing down its growth and cessation of dispersion. The efficiency of using the vibration method for determining the viscosity of the hydrated lime – water system is shown.

The work presents the results of quantitative assessment of heavy metals (HM) content in bottom sediments of the coastal zone near the Karadag nature Reserve. The data were obtained as a result of field studies in 2016-2018. Estimated СС and Cо coefficients and Zc were calculated. It was shown that arsenic concentration limits were exceeded everywhere in the samples. The nickel, lead, copper and zinc limits were found to have been exceeded in some locations. Ecological and geochemical assessment of water and bottom sediments quality in the section of Karadag water area has been made.

The object of research is environmentally friendly water exchange systems in industry and utilities. At existing enterprises, in the process of modernizing water use systems, they often switch to the use of corrosion inhibitors for metals and scale formation. After a long period of operation of these systems, equipment replacement is not performed. One of the most problematic places of reconstruction is the presence of scale formation and corrosion products on the inner surface of heat exchange equipment. These formations reduce the efficiency of heat transfer and level the effectiveness of corrosion inhibitors and scale builders. In this paper, the effectiveness of compositions proposed as etching solutions for cleaning metal surfaces from a sedimentary deposit, as well as stabilizers of scale formation, is evaluated. In the course of the study, compositions based on inorganic acids in the presence of urotropin, urotropin with thiocarbamide were used. The research results indicate that the P-29 composition is characterized by the lowest corrosivity among the options considered. The deep corrosion rate is 0.118907 mm/year. The rate of destruction of chemically shrunk gypsum is at least 90 %. For the purpose of effective and long-term use of heat exchange equipment, it is advisable to use corrosion and scale inhibitors. The paper presents a new P-33 composition, which at a concentration of 20 mg/dm 3 (water hardness 230 – 490 mg-eq/dm 3 , t=90 °C, τ=5 h) provides a stabilization effect of 56.0 – 93 . 3 %, and the anti-scale effect – 95.5 – 99.3 %. With an increase in the concentration of the reagent to 50 %, the stabilization and anti-scale effects reach 100 %. The developed compositions for cleaning the surfaces of heat exchange equipment based on affordable low-cost reagents, which are dominated by analogues in efficiency, are characterized by low corrosivity and ensure removal of poorly soluble chemically resistant substances (gypsum) from the metal surface. P-33 composition is superior to analogs in that it provides stabilization of the precipitated structure in gypsum solutions in the presence of calcium and magnesium carbonates at high temperatures.

Abstract The paper evaluates application of CO2 injection for the control of water encroachment from the aquifer into gascondensate reservoir under active natural water drive. The results of numerical simulations indicated that injection of CO2 at the initial gas-water contact (GWC) level reduces the influx of water into gas-bearing zone and stabilizes the operation of production wells for a longer period. The optimum number of injection wells that leads to the maximum estimated ultimate recovery (EUR) factor was derived based on statistical analysis of the results. The maximum number of injection wells at the moment of CO2 break-through into production wells for homogeneous reservoir is equal to 6.41 (6) and for heterogeneous – 7.74 (8) wells. Study results indicated that with the increase of reservoir heterogeneity, denser injection well pattern is needed for the efficient blockage of aquifer water influx in comparison to homogeneous one with the same conditions. Gas EUR factor for the maximum number of injection wells in homogenous model is equal 64.05% and in heterogeneous – 55.56%. Base depletion case the EURs are 51.72% and 49.44%, respectively. The study results showed the technological efficiency of CO2 injection into the producing reservoir at initial GWC for the reduction of water influx and improvement of ultimate hydrocarbon recovery.