homework
Breeder Reactors
Overview, Design, and History
Mohammed Chamma - 6379153December 1, 2014
"Fissile" vs. "Fissionable"
Fissile: Undergo fission with low-energy neutrons with high probability.
Fissionable: Undergo fission with high-energy neutrons with low probability.
Uranium-235 is fissile.
Uranium-238 is fissionable.
Motivation
Lots of Uranium-238... Not much of Uranium-235
Recycles nuclear waste
Produces more fissile material than it consumes
Uranium-238 Fuel
Thorium-232 Fuel
Reactor Design
The breeding reactions require high energy, fast neutrons. Water can't be used as a coolant since it is a strong moderator and will slow down the neutrons.
Liquid Metal Coolants
- Mercury
- Liquid Lead
- Liquid Tin
- Liquid Sodium
Liquid Metal Fast Breeder Reactors (LMFBR)
Integral Fast Reactor
Combine a breeder reactor with a waste reprocessing facility nearby. Waste is taken from the core and quickly reprocessed to replenish the core and continue the reaction. No fissile material needs to be removed from the site.
Allows for the complete use of a Uranium sample.
History from the 1950s
Prototype breeder reactors have been built by the US, France, India, Germany, the UK, and Russia. Plagued by technical problems, high costs, and distrust from the public.
History from the 1950s
The first breeder in the world was the Experimental Breeder Reactor I (EBR-I) built in the US.Proof-of-concept reactor that generated enough electricity to power the site.
EBR-II in 1964
Replaced EBR-I and was meant as a prototype integral fast reactor
Shut down in 1994 by congress despite very positive results.
France from 1967+
- Built Rapsodie, Phénix, and Superphénix
- Superphénix was the largest breeder reactor in the world. Shut down in 1997
Future
- India very interested in breeder reactors --largest Thorium reserves in the world.
- Despite the high costs and setbacks, the energy payoffs and nuclear waste benefits are still attractive and research is still active.