Consideration has been given to the distinctive features of multistep concentration of all the molybdenum isotopes in a cascade with a varying type of stages as far as the number of gas centrifuges ...is concerned. A computational experiment on separation of molybdenum hexafluoride was conducted. A procedure of calculation from the cuts of partial flows of the stages was used which takes account of the dependence of the separation factors of gas centrifuges on their feed flow and the flow-division coefficient. It has been shown that the high efficiency of separation processes is attained with a large number of stages and gas centrifuges and small feed flows of the cascade.
A method has been developed for simultaneous concentration of molybdenum isotopes with intermediate atomic mass in two additional products of a multi-flow cascade with a given number of centrifuges ...in stages. The method takes into account the dependence of the separation factors of the cascade stages on the feed flow of gas centrifuges and the flow division coefficient, which makes it possible to calculate the most efficient operating modes. On its basis, a computational experiment on the separation of molybdenum hexafluoride was carried out. The influence of factors related to the cascade feed flow and to the number of stages and gas centrifuges is investigated. It is shown that the feed flows and the separation factors of the stages of gas centrifuge cascades differ significantly from rectangular and rectangular-partitioned cascades.
Aspects of separation potentials for a multicomponent mixture of isotopes are considered. In order to separate isotopes of reprocessed uranium and germanium in cascades with high separation factors ...corresponding to gas centrifuges, a computational experiment was carried out. The application of potentials for calculating the separation power of elements, stages, and cascades is analyzed. Potentials that provide a satisfactory assessment of the actual separation power for the stages and the cascade, thus determining the costs of the separation work, are established. This characteristic, along with the separation power of the element, is virtually independent of the used potential type.
A method is proposed for calculating a gas-centrifuge cascade with variable separation factors depending on their feed flow and flow division factor. On its basis, a computational experiment was ...performed on the separation of germanium tetrafluoride, nickel trifluorophosphine, and tungsten hexafluoride in a cascade with a specified number of gas centrifuges in steps. The most efficient multistage separation schemes for the production of highly concentrated isotopes were determined.
The paper considers features of enriched regenerated uranium hexafluoride purification from
232, 234, 236
U in a double cascade with a supply of uranium hexafluoride wastes for the additional feeding ...of the first cascade. The effective purification from
236
U is carried out in the first cascade at a
235
U concentration of less than 20% in long cascades with a large number of stages. The parameters of the second cascade, fed by the product of the first one, which significantly reduce the concentration of
232, 234
U in the wastes, were determined. Its reduction with uranium hexafluoride wastes ensures the compliance with the requirements of the ASTM C996-20 specification, established for enriched industrial uranium hexafluoride.
The article presents a computational experiment on the purification of enriched regenerated uranium hexafluoride from
232,234,236
U using three-cascade schemes. The proposed schemes meet the ...requirements of the ASTM C996-20 specification for the purified product, which are established for enriched industrial uranium hexafluoride. A three-cascade scheme with additional feeding of the first and third cascades using waste uranium hexafluoride proved to be the most effective. In order to decrease the
232,234,236
U concentration and separation costs, the streams corresponding to the contaminated waste uranium hexafluoride are withdrawn from the cascades. The waste stream of the second cascade, which is reduced by natural uranium, is directed to feed the third cascade, where the resulting low enriched uranium hexafluoride is formed.
A method has been developed for calculating the parameters of cascades with an assigned number of gas centrifuges in the stages whose separation factors depend on their feed flow and the flow cut. ...Based on this method, a computational experiment was conducted on separation of molybdenum hexafluoride and concentration of
92,98,100
Mo isotopes with a low neutron-capture cross section in the outgoing streams of ordinary and double cascades. The author has determined the features of obtaining isotopically modified molybdenum from waste and selected products of such cascades, which is suitable for creating reactor materials with improved thermophysical characteristics. The influence of the factors associated with the feed flow of cascades and the types of stages, as far as the number of gas centrifuges is concerned, has been studied. It has been shown that the feed flows and the separation factors of the stages of gas-centrifuge cascades differ significantly from rectangular and rectangular-partitioned cascades.
Aspects of the lowering of the
232,234,236
U concentration in regenerated uranium hexafluoride are considered. A three-cascade purification scheme including dilution with waste uranium or natural raw ...material at an intermediate stage is proposed. A computational experiment was performed to determine the parameters of purification of regenerated uranium hexafluoride of each isotope
232,234,236
U. It is shown that the overall product formed after dilution with natural raw materials and enrichment in a third cascade satisfies the ASTM C996-20 specifications for enriched commercial uranium hexafluoride.
Aspects of the two-stage concentration of two isotopes with close intermediate atomic mass in a cascade with a specified number of gas centrifuges in steps were considered. A computational experiment ...on the separation of molybdenum isotopes was performed. The computational procedure employs the partial flow cuts of the steps, and takes into account the dependence of the separation coefficients of gas centrifuges on their feed flow and the flow division factor. As an example, it is shown for the concentration of
95,96
Mo and
96,97
Mo that high separation efficiency is achieved by choosing an individual ratio of enrichment factors of the steps, a large number of steps and gas centrifuges, and low feed flows of the cascade.
A method of calculating and optimizing a multi-flow cascade with a specified number of gas centrifuges in stages on cuts of their partial flows were developed. A special feature of the method is an ...iterative fitting of the separation coefficients of the gas centrifuges that depend on the feed flow and the division factor of the flow. A computational experiment was conducted on the separation of molybdenum hexafluoride and concentration of the isotopes
98
Mo in an additional product and
100
Mo in the waste of the cascade. The basic factors that affect the efficiency in concentrating the components and are associated with the cascade feed and the types of stages in terms of the number of gas centrifuges are determined. It is shown that the feed flows and the separation coefficients of the stages of such cascades differ significantly from those of rectangular and rectangular-sectioned cascades.
