A Comparison of Fast Thorium Breeder Reactor Designs With Oxide and Metallic Fuels

Abstract

Loading of seedless thoria rods in internal blanket regions and using them later as part of seeded fuel assemblies is the central theme of the thorium breeder reactor (ATBR) concept [1]. The fast reactors presently consider seedless blanket region surrounding the seeded core region. This results in slower fissile production rate in comparison to fissile depletion rate per unit volume. The overall breeding is achieved mainly by employing blanket core with more than double the volume of seeded core. The blanket fuel is discharged with fissile content of ∼30g/kg, which is much less than the asymptotic maximum possible fissile content of 100g/kg. This is due to smaller coolant flow provided for in the blanket regions. In a newly proposed fast thorium breeder reactor (FTBR) [2], the blanket region is brought in and distributed through out the core. By this the fissile depletion and production rates per unit volume become comparable. The core considered simultaneous breeding from both fertile thoria and depleted uranium and hence the concept can be called as fast twin breeder reactor as well. Sodium is used as coolant. The blanket fuel rods achieve nearly 80% of the seed fuel rod burnup and also contain nearly the maximum possible fissile content at the time of discharge. In this paper a comparison of FTBR core characteristics with oxide and metallic fuel are compared.

Reprocessing free nuclear fuel production via fusion fission hybrids

“…Even if the U-Pu and Th-U are combined, the BR is lower. A value of 1.35, optimistically, may be attainable [46,47].…”

Thorium breeder reactors as a power source for 21st century and beyond

“…The core had a net breeding potential of 1.2 in oxide version and 1.28 in metallic version, and the discharge burnups were 139 and 119 MWD/kgM in the oxide and metallic versions. The Pu inventory per batch of 120 FAs was 3.4 T …”

“…The core had a net breeding potential of 1.2 in oxide version and 1.28 in metallic version, and the discharge burnups were 139 and 119 MWD/kgM in the oxide and metallic versions. The Pu inventory per batch of 120 FAs was 3.4 T. 24 The FTBR and ATBR designs can work in tandem with Pu output of ATBR fed in FTBR to obtain Pu of better quality and then used back in ATBR/FTBR. The combined breeding potential may be just under 2.…”