| 摘要 |
<p>The present invention relates to a process and to a cascade for infinitely variably setting the U235 tails concentration in the operation of centrifuge cascades for the separation of the uranium isotopes in a gaseous uranium isotope mixture, wherein each cascade stage (Sn) is connected to a separate common conduit for feeding in the isotope mixture to be separated (feed header), for discharging the light fraction (product header) and for discharging the heavy fraction (tails header), the feed header of each cascade stage (Sn) is connected, when viewed in the direction of enrichment, to the product header of the cascade stage (S-1) disposed therebelow and to the tails header of the cascade stage (S+1) disposed thereabove, the starting mixture (feed) is fed into the bottom cascade stage (S0), the U235 enriched mixture (product) is discharged from the uppermost cascade stage (S+3) and the U235 deriched mixture (tails) is discharged from the lowermost cascade stage (S-2). To be able to vary the tails concentration of the cascade, the present invention proposes the following measures: a) the pressure of the mixture in the feed headers (3) of each cascade stage (Sn) is matched, in every operating state, to the pressure of the starting mixture (F), b) in order to increase the U235 concentration in the tails stream (T), the gas streams in the product headers (5n) of the cascade stages (Sn) are choked and the cascade feed stream (F) is increased so as to keep constant the U235 concentration in the product stream (P); c) in order to decrease the U235 concentration in the tails stream (T), the gas streams in the tails headers (4n) of the cascade stages (Sn) are choked and the cascade feed stream (F) is reduced so as to keep constant the U235 concentration in the product stream (P).</p> |
