Видання зареєстровані авторами шляхом самоархівування

Permanent URI for this communityhttps://devessuir.sumdu.edu.ua/handle/123456789/1

Browse

Search Results

Now showing 1 - 5 of 5
  • Item
    Experimental Studies and Condition Monitoring of Auxiliary Processes in the Production of Al2O3 by Sol–Gel Technology
    (MDPI, 2022) Склабінський, Всеволод Іванович; Склабинский, Всеволод Иванович; Sklabinskyi, Vsevolod Ivanovych; Ляпощенко, Олександр Олександрович; Ляпощенко, Александр Александрович; Liaposhchenko, Oleksandr Oleksandrovych; Piteľ, J.; Павленко, Іван Володимирович; Павленко, Иван Владимирович; Pavlenko, Ivan Volodymyrovych; Скиданенко, Максим Сергійович; Скиданенко, Максим Сергеевич; Skydanenko, Maksym Serhiiovych; Острога, Руслан Олексійович; Острога, Руслан Алексеевич; Ostroha, Ruslan Oleksiiovych; Юхименко, Микола Петрович; Юхименко, Николай Петрович; Yukhymenko, Mykola Petrovych; Simeiko, K.; Demianenko, M.; Volf, M.; Starynskyi, O.; Юрченко, Олександр Юрійович; Юрченко, Александр Юрьевич; Yurchenko, Oleksandr Yuriiovych; Мандрика, О.
    Powders and granules of heavy metal oxides produced through condition monitoring are in high demand as intermediate products for obtaining fine-grained ceramics for a wide range of applications, i.e., nuclear fuel and fuel elements for nuclear power plants. Sol–gel technology to produce nuclear fuel (UO2), as well as catalysts (ThO2) for organic synthesis in the form of granules from pressed microspheres, is a promising method to obtain powders and granules of heavy metal oxides (fine-graded ceramics). Al2O3 was selected as the model analog at the stages of obtaining a solution of heavy metal and sol, the formation and gelation of droplets, and the preparation of gel spheres and their further washing and drying, as well as recovery and firing of particles. In the study, the main parameters were substantiated, e.g., the diameter and angle of inclination of the axis for the holes in the perforated shell, the multiplicity of sol circulation before the holes, the coefficients of liquid (sol) flow rate, the oscillation frequency of the disperser, and the concentration of surfactant and acid in sol. All of these parameters affect the characteristics of the granules that are obtained by sol–gel technology. Moreover, recommendations to increase productivity and the energy efficiency of production were also given. In particular, it was found that oscillation frequency in a range of 70–80 Hz leads to a granulometric composition of the obtained granules of 2.0–2.2 mm. A hole of 0.85 mm and a frequency of 100 Hz slightly change this range to 1.2–2.0 mm, while maintaining monodispersity.
  • Item
    Integration of Processes of Radionuclide-Contaminated Territories Decontamination in the Framework of their Ecological-Socio-Economic Rehabilitation
    (Polish Society of Ecological Engineering (PTIE); Lublin University of Technology, 2022) Черниш, Єлізавета Юріївна; Черныш, Елизавета Юрьевна; Chernysh, Yelyzaveta Yuriivna; Balintova, M.; Shtepa, V.; Скворцова, Поліна Олексіївна; Скворцова, Полина Алексеевна; Skvortsova, Polina Oleksiivna; Скиданенко, Максим Сергійович; Скиданенко, Максим Сергеевич; Skydanenko, Maksym Serhiiovych; Fukui, M.
    Large-scale disasters at nuclear power plants (NPPs) and their consequences are still the subject of discussion by the world scientific community, which makes mankind recognize the unsolved problem of radiation pollution. Accordingly, the search for new effective biocomposite materials with high sorption capacity to eliminate harmful effects associated with radiation contamination of large territories is an urgent task on a global scale. This paper is devoted to the study of the decontamination processes of the areas contaminated with radionuclides, the search for new mechanisms of fixation of radionuclides and heavy metals in the soil using the matrix material of different origin. In order to intensify the process of radionuclide fixation in the soil-plant system, the method consisting of introducing into the soil the organic-mineral biocomposite based on sewage sludge and phosphogypsum after anaerobic fermentation was proposed. It is necessary to further study the processes of sorption and radionuclides solubilization due to complexation with organic agents present in matrix materials of different nature. The mechanisms of radionuclide and heavy metal fixation using matrix material of different origin were analyzed, and a general model was formed. The direction of integration of radionuclide-contaminated soil decontamination technologies into the process of ecological, social, and economic development of the territories under rehabilitation after the accidents at the Chernobyl NPP and Fukushima-1 NPP is proposed.
  • Item
    Modeling of Technological Processes for a Rectification Plant in Second-Generation Bioethanol Production
    (MDPI, 2021) Ляпощенко, Олександр Олександрович; Ляпощенко, Александр Александрович; Liaposhchenko, Oleksandr Oleksandrovych; Маренок, Віталій Михайлович; Маренок, Виталий Михайлович; Marenok, Vitalii Mykhailovych; Скиданенко, Максим Сергійович; Скиданенко, Максим Сергеевич; Skydanenko, Maksym Serhiiovych; Павленко, Іван Володимирович; Павленко, Иван Владимирович; Pavlenko, Ivan Volodymyrovych; Ochowiak, M.; Mizakova, J.; Pitel, J.; Стороженко, Віталій Якович; Стороженко, Виталий Яковлевич; Storozhenko, Vitalii Yakovych; Смирнов, Василь Анатолійович; Смирнов, Василий Анатольевич; Smyrnov, Vasyl Anatoliiovych; Шматенко, В'ячеслав Анатолійович; Шматенко, Вячеслав Анатольевич; Shmatenko, Viacheslav Anatoliiovych
    The article deals with the recent developments in the fuel industry, considering the permanent increasing requirements for fuel quality and environmental safety. The work aims to study various technological modes at the rectification unit to produce fuel bioethanol from lignocellulosic biomass. The main goals are to solve applied scientific problems of rational designing and technological optimization to obtain boundaries of energy consumption to ensure the quality of bioethanol sufficient for a consumer. Recent approaches for numerical simulation of chemical technological processes were applied to study the operating processes and optimize technological parameters. The plant model was designed from various modules that allow us to simulate technological processes efficiently and accurately for all the primary units of the rectification equipment. The methodology based on the activity coefficient UNIFAC model of phase equilibrium was applied. As a result, a mixture with 74% of bioethanol 9% of impurities was obtained in the brew column. In the epuration column, a mixture of 46% bioethanol and 2.2% of impurities was obtained in bottoms. Finally, in the alcohol column, the mass fraction of distillate of 96.9% and impurities of 2.7% were reached. The numerical simulation results can be applied in recent fuel technologies and designing the corresponding biofuel plants.
  • Item
    Effect of Superimposed Vibrations on Droplet Oscillation Modes in Prilling Process
    (MDPI, 2020) Павленко, Іван Володимирович; Павленко, Иван Владимирович; Pavlenko, Ivan Volodymyrovych; Склабінський, Всеволод Іванович; Склабинский, Всеволод Иванович; Sklabinskyi, Vsevolod Ivanovych; Piteľ, J.; Kuric, I.; Іванов, Віталій Олександрович; Иванов, Виталий Александрович; Ivanov, Vitalii Oleksandrovych; Скиданенко, Максим Сергійович; Скиданенко, Максим Сергеевич; Skydanenko, Maksym Serhiiovych; Ляпощенко, Олександр Олександрович; Ляпощенко, Александр Александрович; Liaposhchenko, Oleksandr Oleksandrovych
    This article was aimed to solve an urgent problem of ensuring quality for prilling processes in vibrational prilling equipment. During the research, the need for the application of vibrational prilling to create a controlled impact on the process of jet decay on droplets with the proper characteristics was substantiated. Based on the experimental and theoretical studies of the process of decay of a liquid jet into drops, axisymmetric droplet oscillation modes for the different frequencies were observed. Frequency ranges of transition between modes of decay of a jet into drops were obtained. As a result, the mathematical model of the droplet deformation was refined. The experimental research data substantiated this model, and its implementation allowed determining the analytical dependencies for the components of the droplet deformation velocity. The proposed model explains the existence of different droplet oscillation modes depending on the frequency characteristics of the superimposed vibrational impact. Based on an analytical study of the droplet deformation velocity components, the limit values of the characteristics defining the transition between the different droplet oscillation modes were discovered. Analytical dependencies were also obtained to determine the diameter of the satellites and their total number.
  • Item
    The Mathematical Model for the Secondary Breakup of Dropping Liquid
    (MDPI, 2020) Павленко, Іван Володимирович; Павленко, Иван Владимирович; Pavlenko, Ivan Volodymyrovych; Склабінський, Всеволод Іванович; Склабинский, Всеволод Иванович; Sklabinskyi, Vsevolod Ivanovych; Doligalski, M.; Ochowiak, M.; Mrugalski, M.; Ляпощенко, Олександр Олександрович; Ляпощенко, Александр Александрович; Liaposhchenko, Oleksandr Oleksandrovych; Скиданенко, Максим Сергійович; Скиданенко, Максим Сергеевич; Skydanenko, Maksym Serhiiovych; Іванов, Віталій Олександрович; Иванов, Виталий Александрович; Ivanov, Vitalii Oleksandrovych; Włodarczak, S.; Woziwodzki, S.; Kruszelnicka, I.; Ginter-Kramarczyk, D.; Olszewski, R.; Michałek, B.
    Investigating characteristics for the secondary breakup of dropping liquid is a fundamental scientific and practical problem in multiphase flow. For its solving, it is necessary to consider the features of both the main hydrodynamic and secondary processes during spray granulation and vibration separation of heterogeneous systems. A significant difficulty in modeling the secondary breakup process is that in most technological processes, the breakup of droplets and bubbles occurs through the simultaneous action of several dispersion mechanisms. In this case, the existing mathematical models based on criterion equations do not allow establishing the change over time of the process’s main characteristics. Therefore, the present article aims to solve an urgent scientific and practical problem of studying the nonstationary process of the secondary breakup of liquid droplets under the condition of the vibrational impact of oscillatory elements. Methods of mathematical modeling were used to achieve this goal. This modeling allows obtaining analytical expressions to describe the breakup characteristics. As a result of modeling, the droplet size’s critical value was evaluated depending on the oscillation frequency. Additionally, the analytical expression for the critical frequency was obtained. The proposed methodology was derived for a range of droplet diameters of 1.6–2.6 mm. The critical value of the diameter for unstable droplets was also determined, and the dependence for breakup time was established. Notably, for the critical diameter in a range of 1.90–2.05 mm, the breakup time was about 0.017 s. The reliability of the proposed methodology was confirmed experimentally by the dependencies between the Ohnesorge and Reynolds numbers for different prilling process modes.