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The Nuclear Fuel Cycle. Name Affiliation Title. Nuclear fuel. What is it? Where does it come from? How is it used?. Nuclear fuel pellets are stacked vertically in long metal tubes to power commercial nuclear reactors. Photo courtesy of Orano USA ( Areva ) and the NRC. It starts with U.
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The Nuclear Fuel Cycle Name Affiliation Title
Nuclearfuel • What is it? • Where does it come from? • How is it used? Nuclear fuel pellets are stacked vertically in long metal tubes to power commercial nuclear reactors. Photo courtesy of Orano USA (Areva) and the NRC.
Uranium milling • Ore is crushed • Uranium is separated • U3O8 “yellow cake”produced
Uranium conversion to UF6 gas • Impurities removed • Uranium combined with fluorine • UF6 gas produced
U enrichment UF6 enriched from 0.7% 235U to 3%-5% 235U Centrifugation Diffusion
Fuel fabrication Uranium oxide ceramic fuel pellets
Fuel fabrication A pressurized water reactor fuel assembly
Inside the reactor Cherenkov radiation glowing in the core of the INL Advanced Test Reactor.
In the reactor, 235U fissions to produce . . . Neutron Lighter element Energy Uranium-235 Neutron Neutron Energy Lighter element Neutron Neutrons may • Cause new fissions to occur • Be absorbed to form unstable, radioactive nuclide
Fuel consumption in the reactor • Fuel is in reactor for 4 – 6 years • Uranium consumed • Fission products and transuranics produced Fresh Fuel 100% uranium dioxide (UO2) 1% 95% uranium dioxide (UO2) 4% Transuranics Fission Products Used Fuel
Low-level waste disposal sites • Four low-level waste disposal facilities: • Richland, WA • Clive, UT • Barnwell, SC • Andrews, TX
High-level “waste” Dry cask storage
Used nuclear fuel storage • Used fuel first stored in pool at least 5 years • Cooling and shielding Older fuel can move to dry casks • Steel and concrete shields • Air cools
Geologic repository • The choice of countries worldwide • U.S. has studied Yucca Mt.
Fuel consumption in the reactor Fresh Fuel 100% uranium dioxide (UO2) 1% 95% uranium dioxide (UO2) 4% Transuranics Fission Products Used Fuel
Reprocessing World Nuclear Association
Research Electroplated uranium from pyroprocessing Sodium cooled fast reactor
Recycling nuclear fuel • Continuously recycling fuel can reduce spent fuel waste volume by over 95% • Reduces isolation time from 1000s of years to 100s • Remaining waste is placed in robust containers designed for safety and shielding