Vol 121, No 6 (2017)

A high-efficiency once-through steam generator is used in the RITM-200 reactor for the universal nuclear icebreaker. The new design necessitated experimental validation of the technical characteristics of the steam generator taking into account the integral arrangement of the steam-generating block. To this end a model of the steam-generator cassette was developed and tested at OKBM Afrikantov. The experimental studies of the model of the steam-generator cassette confirmed the heat-engineering and hydrodynamic design characteristics of the steam generator in the RITM-200 reactor.

Modeling of the thermodynamic interaction of beryllium minerals with different opening agents is performed in order to validate the proposed methods of opening beryllium orr at the Ermakovskoe deposit and the structural design of technological equipment blocks. It is found that when beryllium minerals interact with sulfuric acid and alkali the following stability sequences of the minerals are observed: bertrandite–phenakite–beryl with acid and the reverse sequence with alkali. In the case of alkali, the opening of the composition of the reaction products depends on the alkali consumption.

A scheme is proposed for purifying native uranium hexafluoride in a cascade with one feed stream, two product streams, and one waste stream. The cascade is reckoned as quasi-ideal with adjustments of the obtained ²³⁵U concentration for the prescribed content in the external streams. A product with native ²³⁵U concentration and low ²³⁴U concentration is produced in the intermediate product stream of the cascade. Low-enrichment uranium hexafluoride intended for fabricating nuclear fuel is obtained in the main product stream. A high-quality diluent for high-enrichment uranium or low-enrichment uranium hexafluoride with ²³⁴U content less than the ASTM C 996–10 limit norm by a factor of 1.5–2.5 can be produced from the intermediate product.

One method of separating hydrogen isotopes is chemical isotopic exchange of hydrogen with liquid water, combined with electrolysis of water. At present, different mathematical models are used to calculate the characteristics of newly developed setups. They all have the problem of inadequate data on the characteristics of the chemical isotopic exchange process occurring at medium and high deuterium concentrations. The present work is devoted to investigating one stage of chemical isotopic exchange – catalytic isotopic exchange between hydrogen and water vapor at high deuterium concentrations in application to the catalyst RKhTU-3SM. It is shown that the experimental rate constant of isotopic exchange for the pair protium – deuterium increases by almost a factor of two, while for exchange with tritium increasing the deuterium concentration from 5 to 95% does not change the experimentally observed rate constant to within the measurement error.

The transmission of 1.054 μm probing laser radiation by laser liquid \( {\mathrm{POCl}}_{3^{\hbox{--} }}{{\mathrm{SnCl}}_{4^{\hbox{--}}}}^{235}{\mathrm{UO}}_2^{2+}\hbox{--} {\mathrm{Nd}}^{3+} \) excited by uranium fission fragments was measured. It is shown that for liquid pressure 10.1 MPa the transmission of the liquid does not exceed 1. It is found that the transmission of the liquid in the active element with aperture 25 mm is approximately 4 times lower than in an element with aperture 10 mm. A qualitative explanation of the observed effect is proposed on the basis of the assumption that light was scattered by radial acoustic density waves in the liquid. This effect can serve as one of the primary reasons for the absence of lasing during nuclear pumping of the liquid under discussion. Methods of reducing the influence of this effect are examined.