Nuclear Power Plant How A Nuclear Reactor Works.
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Transcript of Nuclear Power Plant How A Nuclear Reactor Works.
Nuclear Power Plant How A Nuclear Reactor Works Pressurized
Water Reactor - Nuclear Power Plant A. Main Parts of a Nuclear
Reactor
Fuel Pellets stacked in long metal tubes (fuel rods).These are
arranged in bundles in the reactor with space between them for
control rods. Moderator Slows down neutrons so they have a greater
probability of colliding with another uranium atom.Usually water or
graphite. A. Main Parts of a Nuclear Reactor (continued)
3.Control System Control rods are filled with substances that
absorb neutrons (boron or cadmium).These help control the rate of
the reaction. 4.Heat Removal System The reactor must be cooled to
prevent overheating and melting of the core.Heat is carried away by
water and used for steam production. 5.Radiation Shield Thermal
(steel) shield protects the walls of the reactor vessel from
radiation damage.A concrete shield protects the workers from
radiation. B. Disposal Of Nuclear Waste
When most usable uranium has fissioned, the spent fuel assembly is
removed from the reactor. Until a long term storage facility is
operational (Yucca Mountain, NV?), spent fuel is stored in water
pools at the reactor site. Water removes leftover heat and serves
as a radiation shield. Typical water pools for nuclear waste
storage Underground disposal of radioactive waste (in Finland)
C.Nuclear Meltdown Refers to melting fuel in a reactor when there
is an inability to remove heat effectively. Causes include a loss
of coolant in the system and/or failure of the reactor to shut down
when faulty. If a meltdown does occur, a release of radiation
occurs only if there is a major failure in the containment
structure (pressure, fire, explosion). C. Nuclear Meltdown
(continued)
Chernobyl disaster Ukraine (Soviet Union), 1986 Worst nuclear power
plant accident in history 31 people died during the accident
itself, but more people suffered long-term effects like cancer and
deformities C. Nuclear Meltdown (continued)
Fukushima Daini Nuclear Power Plant Japan, March2011 Occurred after
the power plant was hit by a tsunami Although no fatalities were
reported after the incident, over 300,000 people had to evacuate
the area, and almost 16,000 died due to the earthquake and
tsunami