Cascade Performance for Large Separation Factors

The performance of small isotope enrichment cascades that have large separation factors is examined. A quantity called the separative work gain is derived under the assumption of a small inlet assay. This concept simplifies the determination of optimum separation factors, and verifies the common practice of using the same values for these factors for each stage in a cascade. Simple relations are provided for a non-ideal, counter-current cascade of arbitrary size. They are utilized to determine a pricing strategy and to estimate a value for the U.S. stockpile of diffusion plant UF6 tailings. The value depends on the separation factors and cost of separative work, but may well be several billion dollars.