One of the variants of the projected nuclear reactors possessing increased passive protection are reactors with coated particles and spherical fuel elements, one of the main components of which is pyrocarbon. Pyrocarbon has a high radiation and corrosion resistance, therefore, the researches aimed at the disposal of radiation wastes are also promising, as the problem of radiation wastes disposal is urgent problem not only for Ukraine, but for the whole world. It should be noted that due to its unique properties, pyrocarbon can be used in various fields of science and industry. For several years, the Gas Institute of NASU conducted studies of the production of pyrocarbon coatings through the pyrolysis of hydrocarbon gases in reactors with electrothermal fluidized bed. In order to determine the possibility of using pyrocarbon coatings obtained by the Gas Institute of NAS of Ukraine, it is necessary to conduct studies of their material-science characteristics and properties. The article presents studies of the assessment of density, purity, corrosion resistance and microrelief of pyrocarbon coatings. Intermediate conclusions concerning the possibility of using the obtained pyrocarbon were made. Bibl.16, Fig. 2, Tab.1.

When implementing a number of high-temperature processes with heat supply to the reaction zone (allothermic processes), it is impossible or economically inexpedient the burning of fossil fuels to achieve the required temperature level. The possibilities of these processes implementation through the use of electrothermal fluidized bed (ETFB) techniques are considered. Such processes include, for example, the production of hydrogen by the pyrolysis of hydrocarbon gases, the production of silicon carbide and other carbides, the production of artificial graphite and the thermal purification of natural graphite, the high-temperature heating of gases and gas mixtures. These processes can be carried out in the temperature range of 600–3000 °С using fine-dispersed materials or directly in the gas phase using ETFB. In a number of processes ETFB technology can be applied as a source of high temperature gas production, used either for the implementation of this technological process, or for ensuring the operation of technological or heat engineering equipment. Also considered the main structural characteristics of the equipment that ensure the implementation of processes in the ETPS. Bibl. 37.

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.

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Introduction. As a result of termination of cooperation with Russian Federation, it became necessary to diversifysupplying not only nuclear fuel, but also goods and materials for assembly, operation, technical maintenance, and repair of power engineering equipment.Problem statement. Critically important products include, in particular, gaskets for sealing the plug-type connections of reactor units with water-cooling equipment, for example, ПГВ-1000M steam generators. For the time being, the existing reserves of TEG (thermally expanded graphite) gaskets imported from Russia for upgraded steam generators ПГВ-1000M and ПГВ-213 have been almost exhausted, therefore there is an urgent need for the domestic production of these and other TEG sealers.Purpose. Development of technological framework for manufacturing TEG sealers for the NPP technological equipment. materials and methods. Graphite foil of different manufacturers obtained from original natural graphite, conventional methods for measuring the physico-technical characteristics of sealing gaskets.results. Within the framework of the conducted R&D works, the physical, technical, and physicochemical properties of graphite foils made of natural graphite derivatives by various manufacturers have been established; molds of two standard sizes have been designed and manufactured; the technology for molding the sealers from graphite foil has been tested; specific compression force to obtain the sealers of given density has been determined; specific compression strength of the obtained gaskets has been established.conclusion. The obtained results can be used for developing a new pilot manufacture of TEG sealing gaskets by domestic corporations.K e y w o r d s : thermally expanded graphite (TEG), nuclear power plants, process equipment, and sealers.