Fast Reactor Alternative Studies: Effects of Transuranic Groupings on Metal and Oxide Sodium Fast Reactor Designs

摘要

A 1000 MWth commercial-scale Sodium Fast Reactor (SFR) design with a conversion ratio (CR) of 0.50 was selected in this study to perform perturbations on the external feed coming from Light Water Reactor Spent Nuclear Fuel (LWR SNF) and separation groupings in the reprocessing scheme. A secondary SFR design with a higher conversion ratio (CR=0.75) was also analyzed as a possible alternative, although no perturbations were applied to this model. Metal and oxide fuel SFR designs were both included in the analysis. Initial results showed good agreement between the UREX+1a base cases and data previously published in the literature for the SFR conceptual design. The initial set of perturbations involved varying the external feed to study the so-called vintage problem, which addresses the large variation in burnup and cooling needed to be accommodated in the SFR. Three sets of external feed isotopic vectors were generated for the cases of a low burnup and long cooling time (33 MWd/kg, 30 year cooled LWR SNF), high burnup and medium cooling time (51 MWd/kg, 10 year cooled LWR SNF), and the reference high burnup and short cooling time (51 MWd/kg, 5 year cooled LWR SNF.) Results show that the choice of external feed has little impact on the TRU enrichment, burnup, or cycle length of either the metal or oxide fuel SFR because all the TRU vectors having similar fissile plutonium content.