Speaker
Description
Regarding innovative solution findings for specific nuclear waste, especially in the field of treatment of used nuclear fuel (UNF), the idea of recovery instead of storage and usage of UNF in liquid fuel reactors will be of significantly increasing importance in the future. Recycling by separation and reuse of UNF via chlorination of UNF and target-oriented back feeding into a liquid fuel reactor would provide the possibility to reuse UNF completely and reduce the amount of waste significantly. The Dual Fluid principle applying high temperature and fast-neutrons transmutation is able to burn all today's UNF completely. Hereby, high-temperature distillation is recommended as a solvent-free separation route, avoiding the generation of secondary wastes, unlike other separation techniques, for example, liquid-liquid extraction. Such a separation process via distillation in the form of chlorides has proposed for a target of 1000 t/a of UNF partitioning. The partitioning applies as a pre-processing step on the one hand a single-stage distillation for the separation of particularly volatile chlorides with a downstream condensation stage and on the other hand the simultaneous separation of precious metals and remaining oxides from the molten salt residue. For the main partitioning step, the simulations show that uranium tetrachloride is separated with high purity into a following continuous distillation column with only 1.4-meter column height. In this single column, at least 97-mass% of the UNF is recovered. The remaining portion can be recovered in a second discontinuous distillation column. The following different recycling strategies for the use of distillation as a separation method are available:
- (A) 50-vol% reduction of a final repository for UNF can be achieved by
applying distillation through the separation into single fractions,
mostly by element. - (B) Processing of waste is only related to high
purity uranium tetrachloride separation and refeeding of actinides
into a liquid fuel reactor. After separation only small amounts of
fission products are remaining (e.g., Ce with Pu) which do not cause
relevant neutron absorption. The residual 1 – 5 -vol% of material
will be stored. - (C) Almost complete recycling of UNF and reusing of
all material in a liquid fuel reactor until all long-lived
radioactive isotopes have been transmuted and no final repository is needed.
For all described options, an integrated Waste Management plan has to be set up for the future.
| Speaker's title | Mr |
|---|---|
| Affiliation | University of Szczecin; Institute for Solid-State Nuclear Physics |
| Do you wish to participate as a Young Professional? | Yes |
| Do you wish to be considered for a Young Professional grant? | Yes |
