Plasma isotope separation methods

Abstract

Abstruct-Isotope separation has many important industrial, medical, and research applications. Large-scale processes have typically utilized complex cascade systems; for example, the gas centrifuge. Alternatively, high single-stage enrichment processes (as in the case of the calutron) are very energy intensive. Plasmabased methods being developed for the past 15 to 20 years have attempted to overcome these two drawbacks. In this review, six major types of isotope separation methods which involve plasma phenomena are discussed. These methods are: plasma centrifuge, AVLIS (atomic vapor laser isotope separation), ion wave, ICR (ion-cyclotron resonance), calutron, and gas discharge. The emphasis of this review is to describe the plasma phenomena in these major categories. An attempt was made to include enough references so that more detailed study or evaluation of a particular method could readily be pursued. A brief discussion of isotope separation using mass balance concepts is also carried out.

Wave-driven Countercurrent Plasma Centrifuge

“…In order to compare separation methods, we can consider three quantities to be the most important: the single stage separation factor α, the single stage separative power δU , and the energy cost per unit separative power [6]. If the fraction of the desired isotope in the waste of a separation element is x and in the product is y, the separation factor is α = y (1 − x) /x (1 − y).…”

“…Isotope separation has applications in the production of nuclear fuel [5], and in research and medical isotope production [6]. While most enriched uranium is produced by the gas centrifuge method [7], a significant number of isotopes are still produced by calutrons due to their flexibility [8].…”

Metrics for comparing plasma mass filters

“…The plasma centrifuge has been studied for decades. Early experiments were limited by the Alfven critical ionization velocity (CIV), while later ones had limited throughput because of pulsed operation [2,8,9]. These limits might be overcome by driving rotation with radio frequency waves [10].…”

“…[1][2][3][4] Early techniques like the plasma centrifuge were primarily for isotope separation, but more recent designs have focused on separation of nuclear waste. In order to evaluate these devices, quantitative measures of comparison need to be developed.…”

Drift and separation in collisionality gradients

“…The potential of rotating plasmas for discriminating elements based on atomic mass has long been recognized 1,2 , and led to the development of plasma centrifuges for isotope separation [3][4][5][6] . However, only recently have plasmas been suggested for separating elements with large mass differences [7][8][9][10][11][12] , such as needed for legacy waste disposal or spent fuel reprocessing.…”