Nuke Flashcards
Nuclear is used for…
Electricity
World nuclear use
5% total energy, 13% electricity generation
US nuclear use
9% total energy, 19% electricity generation
Nuclear History
started with bombs in 40s, plants in 50s, 60s/70s mad dash for nuclear plants, 79: 3mile, 87:chernobyl
How does fission work?
neutrons hit U235, blowing it apart into fragments and neutrons; fragments’ kinetic energy converts to heat, makes steam to run a generator. Released neutrons do the same thing to other U235 atoms; water moderates by absorbing some neutrons
Uranium
U235 (fissile), U238 (not fissile)
low enriched uranium is 3-5% U235, and can’t become a weapon
weapons-grade is 90%235
Plutonium
another nuke fuel, make from neutron irradiation of U238, but can become weapons.
Thorium
another nuke fuel–really abundant
not fissile, but turns into U233 to be fissile
Uranium Resources
Australia, Canada, Kazakhstan, Russia
Uranium production
Kazakhstan, Canada, Australia, some african countries
US Uranium
All in the western US–wyoming, New mexico
Where are the worlds operable nuclear plants
US, Europe, Russia, east asia
France & nuclear
Nuclear is 78% of france’s electricity—annndd it exports to other parts of europe.
Nuclear plants in US
104 reactors, 31 states
most important to eastern states
3mile halted development
Uranium Mining (process)
Mostly in-situ leaching mines now; extracts U by injecting acid/base solution into the subsurface
Yellowcake
unenriched material from ISL, used to make fuel pellets and fuel rods
U Mills
turn mined U ore into yellowcake
95% recovery
Fuel enrichment, fabrication
increases concentration of U235, yellowcake–>UF6–>UO2
Control rods
contain neutron poison materials, so operators can insert to moderate or shut down reactor
Pressurized water reactor
most common (65% globally) closed-loop coolant system, heat exchanger, steam turbine, slightly enriched U in thermal reactor
Boiling Water reactor
second most common: 22% globally
two water loops, lower temps, lower cap costs
more risk of contam
Other reactors
CANDU–uses natural or slightly enriched U, and heavy water (deuturium); less enrichment costs, no prolif issues
LWGR/RBMK: only in Russia, use graphite for moderator; chernobyl
Spent fuel pool
pool at plant that temporarily holds spent fuel rods–most are at capacity!
dry cask storage
after 5-10 years, radiation and decay is low enough to store fuel in large casks to cool further
