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Content available Alternative Ways of Extracting Oil from Water Bodies
EN
The article compares the use of sorption and sorption-coagulation methods for cleaning fresh and mineralized oil-containing waters. The sorbents used are thermally expanded graphite obtained by heat treatment of graphite bisulfate in a boiling layer, and activated carbon of BAU-A grade, which is widely used for purification of liquid media from oils and oil products. As an alternative to the sorption method, research was conducted on the application of the sorption-coagulation method with the simultaneous use of aluminum-containing coagulants: aluminum sulfate and aluminum hydroxochloride and activated carbon. It is shown that the advantages of using the sorption method using thermally expanded graphite are based on the high efficiency of oil extraction from water bodies and multiple regeneration of the spent sorbent.
EN
Today, the most convenient and widespread option for cleaning and purifying drinking water is to install reverse osmosis systems directly at the water intake points. When operating reverse osmosis systems, most owners are not concerned about the negative consequences of using such systems. After 3–6 months of using mechanical filters in the first stage of water treatment, such filters are thrown out together with other household waste. They pose a significant threat to the environment. Currently, companies in Ukraine would not collect and dispose of such filters. This direction is undeveloped. There are no corresponding data in the scientific literature. According to authors’ calculations, about 20,000 household reverse osmosis systems are operated per 1 million people today, so it is easy to calculate that 44,000 cartridges with a total polypropylene volume of 26 m3 enter the environment during the year. It is difficult to imagine the real environmental damage from the cartridges of even one city. Therefore, the regeneration of mechanical filters of reverse osmosis systems is quite relevant and essential today. This work aimed to develop an environmentally safe technology for regenerating mechanical filters with the possibility of repeated use. Filter lifespan can be prolonged by special cleaning with sulfuric acid with a fixed pH level. This article highlights the research results on the regeneration the mechanical filters, describes the characteristics of the cleaning process using sulfuric acid and shows the options for environmentally safe waste processing from such regeneration.
EN
The results of electrochemical processing of spent acidic, neutral, and alkaline sulfate-chloride-containing regenerative solutions in two- and three-chamber electrolyzers are presented. It has been determined that the highest current efficiency for the products of electrodialysis can be achieved in the presence of hardness ions when processing acidic sulfate-containing solutions using three-chamber electrolyzers. It has been established that during electrodialysis of alkaline solutions after regeneration of anionites containing chloride ions, accumulation of alkali occurs in the cathodic region, and in the anodic region, chloride ions accumulate due to diffusion through the anion exchange membrane during the first stage, followed by preferential oxidation of chloride ions with liberation of free chlorine during the second stage. It has been shown that electrodialysis can effectively solve the problem of comprehensive processing of neutral, alkaline, and acidic regenerative sulfate-chloride-containing solutions, with the production of alkali and acid at concentrations suitable for reuse in regeneration processes.
EN
The analysis of water conditioning methods for closed water supply systems was carried out in the work. The expediency of using redoxites based on ion exchange materials to combat the corrosion processes in water recirculation systems by preliminary deoxidation of water was shown. Modified KU-2–8, Dowex Mac-3, AB-17–8, Dowex Marathon WBA, AMBERLITE IRA 96 ion exchange resins were used as deoxidizing materials.
EN
The necessity of development of technical solutions that will allow to reduce carbon monoxide emissions of flue gases of industrial productions is substantiated. It is shown that the most rational design solution to the problem of carbon monoxide pollution during the firing of electrode blanks is the use of aerated concrete blocks with a catalyst, which can be quickly and conveniently located directly on the carbon material of the “green” electrodes pouring in the subfloor space of the firing furnaces. Modified by oxides of Mn4+, Fe2+, Fe3+, Cu2+, Cr3+ -catalysts based on aerated concrete were obtained. It is shown that in an empty reactor in the temperature range 200–400 °С the degree of conversion of carbon monoxide in the absence of a catalyst is zero. It is established that on the investigated catalysts based on aerated concrete 100% oxidation of carbon monoxide is achieved at a temperature of 390 °C in the case of using a mixture of catalyst powders 30% CuO + 70% MnO2, 40% CuO + 60% MnO2, 50% Fe (FexCr1-x) 2O4 + 50% MnO2; 50% Fe3O4 + 50 % MnO2. It is determined that the addition of ferrite catalyst powder in aerated concrete in a mixture or without manganese dioxide does not critically affect the mechanical properties of the products.
EN
The catalysts based on natural zeolite-clinoptilolite of Sokyrnytsia deposit modified with oxides of Mn4+, Fe2+, Fe3+, Cu2+, Cr3+ were synthesized. It was determined that 100% conversion of carbon monoxide was achieved at a temperature of 390°C when using the copper-manganese-oxide catalyst (30% CuO + 70% MnO2). It was shown that although the use of the manganese-oxide catalyst provided 92.8% of CO conversion degree, this catalyst had the most advantages for application compared to the other studied solids. The structural parameters of the manganese-oxide catalyst were determined using XRD, SEM, and nitrogen adsorption. The composition of the main elements of the catalyst samples was determined by micro-X-ray spectral analysis. It was shown that using the catalyst containers in chambers heated by flue gases in the fire channels of a multi-chamber furnace for baking of electrode blanks can be one of the constructive solutions to the problem of flue gas purification from carbon monoxide. The environmental safety of the copper-manganese-oxide catalyst application for the treatment of the flue gases of electrode production is justified by obtaining a catalyst from spent sorbents for purification of the manganese-containing natural water and its non-toxicity in the case of burial or storage in landfills.
EN
The processes of the interaction of carbon material (thermoanthracite pouring) with a gas-air mixture in a heat chamber were studied while heating to 800–850°C. The influence of temperature, oxygen and carbon dioxide concentration on the formation efficiency of carbon monoxide, carbon dioxide, hydrogen and methane was determined. A pilot plant was created, which provided heating of the carbon material at the indicated temperatures and regulating the supply of air and carbon dioxide. It was found that a noticeable oxidation of the carbon material in the heat chamber in the presence of oxygen or carbon dioxide occurs at the temperatures above 500°C. Significant concentrations of carbon monoxide were formed at temperatures of 600–800°C. It was shown that when using gas mixtures with an oxygen content of 7–21% minimum concentrations of carbon monoxide are formed at an oxygen content of 14%. At temperatures above 500°C, the formation of hydrogen and methane in gas flows was noted. The methane yield increased with the decreasing oxygen content.
EN
The paper presents the results of the investigation on the efficiency of the potassium ferrate application in water conditioning processes: oxidation of pollutants of different composition by ferrate compounds; clarification of model solutions by coagulation; reduction of corrosive aggressiveness of aqueous solutions. The optimal conditions for the water clarification process using potassium ferrate were: reagent dose 1 mg∙dm-3, pH close to neutral, and temperature 20°C. The oxidation rate of organic substances by the potassium ferrate solutions was 50% when applied in concentrations of 15-20 mg∙dm-3. The studies on the possible application of the reagent as a steel corrosion inhibitor in neutral aqueous media were conducted. The degree of corrosion protection reached 60%, which indicated the prospect of using iron (VI) compounds as inhibitory additives.
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