Flibe blanket concept for transmuting transuranic elements and long lived fission products

A Molten salt (Flibe) fusion blanket concept has been developed to solve th e disposition problems of the spent nuclear fuel and the transuranic elemen ts. This blanket concept can achieve the top rated solution, the complete e limination of the transuranic elements and the long-lived fission products. Small driven fusion devices with low neutron wall loading and low neutron fluence can perform this function. A 344-MW fusion power from D-T plasmas f or thirty years with an availability factor of 0.75 can dispose of 70,000 t ons of the US inventory of spent nuclear fuel generated up to the year 2015 . In addition, the utilization of this blanket concept eliminates the need for a geological repository site for these materials, which is a major adva ntage. This application provides an excellent opportunity to develop and to enhance the public acceptance of the fusion energy for the future. The ene rgy from the transmutation process is utilized to produce revenue. Flibe, l ithium-lead eutectic, and liquid lead are possible candidates. The liquid b lankets have several features, which are suited for this application. It ca n operate at constant thermal power without interruption for refueling by a djusting the concentration of the transuranic elements and lithium-6. These liquids operate at low-pressure, which reduces the primary stresses in the structure material. Development and fabrication costs of solid transuranic materials are eliminated. Burnup limit of the transuranic elements due to radiation effects is eliminated. Heat is generated within the liquid, which simplifies the heat removal process without producing thermal stresses. Th ese blanket concepts have large negative temperature coefficient with respe ct to the blanket reactivity, which enhances the safety performance. These liquids are chemically and thermally stable under irradiation conditions, w hich minimize the radioactive waste volume. The operational record of the M olten Salt Breeder Reactor with Flibe was very successful, which establishe d the technical bases for this application. This paper provides the technic al analyses and the performance of the Flibe blanket concept as an example of this class of blankets.