Optimization of cascades with variable overall separation factors by various efficiency criteria

Construction and operation of separation facilities require considerable investments. That is why the special attention in the theory of isotope separation in cascades is paid to their optimization. The installation allowing obtaining the required quantity of a commercial isotope product by a minimum unit cost it is customary to call as the optimum cascade. However, the use of such the criterion in theoretical calculations is inconvenient, in view of the fact that the cost coefficients are generally inaccessible and can vary depending on external factors. Therefore, theoretically the minimum possible number of separation unit or elements, for instance, gas centrifuges, is often used as the optimization criterion, since its value directly indicates the unit costs. In addition, such criteria as the minimum of the total cascade separation capacity or the minimum of the deviation sums of the maximum possible separation capabilities are also applied in the optimization calculation. In this connection for the case of the cascade with a variable from stage to stage overall separation factor of a centrifuge, the parameters of the cascades optimized by means of various optimization criteria may differ largely. In this paper, we compare the parameters of cascades with the same external conditions, which are optimized by the above criteria. As the criterion to compare all cascades under investigation is chosen the minimum number of separation elements in the installation. The chosen approach allows us to estimate the deviation in the number of gas centrifuge in a case of optimization of a separation plant by different efficiency criteria.