about nuclear power plant

1. MIT NUCLEAR REACTOR LABORATORY
AN MIT INTERDEPARTMENTAL CENTER
Welcome to the MIT
Research Reactor!
David Carpenter
6/25/2015
Research Scientist

2. Constructed in 1958 (MITR-I)
o Upgraded in 1975 (MITR-II)
Power up-rate in 2010 to 6 MW
o 2nd largest university reactor in U.S.
Operates 24/7, 10-week cycles
Uses light water for cooling
Produces radiation for research

3. 3
What I Do – Materials Research

4. 4
How I Got Here

5. What is radiation? Is it dangerous?
How many nuclear power plants are there in the U.S.?
How many are there in Massachusetts?
Where does nuclear power come from?
What does a nuclear power plant look like?
Is nuclear power safe?
5
How Much Do You Know?

6. Radiation is moving particles / waves
We experience radiation as light and heat
6
What is Radiation?

7. If it has enough energy radiation can
oHeat things up
oMove electrons
oMove atoms
This can damage cells, DNA, materials
But, you get lots of radiation every day:
oRadon 55%
oCosmic & Earth 16%
oWhat you eat 11%
oMedical exams 15%
oEverything else 3%
7
Is Radiation Dangerous?

8. There is a LOT of energy contained in atoms.
oFissioning 1 gram of Uranium-235 produces
24,000 kW-hr of energy.
—This is the same as burning 3 tons of coal,
or 12 barrels of oil,
or 50,000 ft3 of natural gas
oMIT consumes 600,000 kW-hr per day
oYour house uses ~20 kW-hr per day
A Nuclear reaction, not a Chemical reaction
8
Why Are We Interested In Nuclear Power?

9. Not burning anything – no exhaust.
We have lots of cheap nuclear fuel
Uranium comes from nicer places:
o Australia 24%
o Kazakhstan 17%
o Canada 9%
o USA 7%
o South Africa 7%
It produces a lot of power – we need a lot of power
9
Why Nuclear Power?

10. 10
Where are there Nuclear Reactors?

11. 11
Where are there Nuclear Reactors?

12. 12
Where are there Nuclear Reactors?

13. 13
Where Does Nuclear Energy Come From?
Split 1 large atom into 2 smaller atoms…
This is where all of the energy from
nuclear power is produced.

14. 14
Fission of Uranium-235

15. This is the process that allows reactors to exist:
oOne free neutron causes one U-235 atom to fission
oThat fission produces 2 or 3 new free neutrons
15
Fission Chain Reaction

16. Nuclear (fission) reactors use Uranium as fuel
16
Nuclear Fuel
Uranium-235 has 92 protons and 143 neutrons
Wikimedia Commons

17. 17
Chart of the Nuclides

18. How do we know if we will get energy?
18
Fission and Fusion
FISSION
FUSION
Wikimedia Commons

19. Boil Water!
1. Produce heat
2. Boil water into steam
3. Use steam to turn a turbine-generator
19
How Does a Nuclear Reactor Work?
This is the same as a:
• Coal power plant
• Oil power plant
• Natural gas plant
• Solar thermal plant

20. 20
How a Nuclear Power Plant Works

21. 21
What a Nuclear Power Plant Looks Like
21
Containment
Building
Cooling
H2O
Nuclear
Reactor
Turbines
Electrical
Generator
Steam
Generator Cooling
Burning
coal

22. 22
Pilgrim - MA
Diablo Canyon - CA
Indian Point - NY
Prairie Island site - MN
Robinson - SC
Surry - VA
Seabrook - NH

23. 23
The Reactor Core

24. We control the fission chain reaction by getting rid of
neutrons
o Insert control rods to absorb neutrons
Fewer neutrons = fewer fissions = less heat
o This can be very fast – full power to shutdown in <1 second!
24
Controlling a Reactor

25. Protect people from radiation
oRules on radiation exposure from man-made sources
Keep radioactive material contained
oKeep the fuel cool and shielded
oPut waste somewhere safe
25
Nuclear Safety

26. 26
Handling Radioactive Material
Reduce dose to people from sources
o Shielding, distance, time
o Dosimeters
Prevent spread of contamination
o Protective clothes
o Monitors

27. 27
MIT Research Reactor Layout

28. 27 positions with 24 fuel elements (15 fuel plates each)
6 control blades (boron),1 regulating rod (cadmium)
28
MITR Core

29. No electricity
Water is at 50°C (120°F), not pressurized
Neutrons for science:
oImaging
oMaterials research
oFundamental properties of matter
oMedicine
oTesting equipment
oUltra-sensitive element detection
29
What We Make

30. 30
How it Works

31. Provides a straight beam of neutrons
for many different uses
o Student experiments and classes
o Medical treatment
o Imaging
o Microchip production
31
Beam Ports

32. A unique capability for advanced materials
research
oIrradiation in water, gas, lead, liquid salt...
oTemperatures from 50°C to 1400°C
oPressures up to 3000 psi
32
In-Core Experiments

33. New sensors
o Fiber-optics
o Crack-length
o Ultrasonic
New materials
o Ceramics (SiC,
graphite, carbon
fiber, MAX-phase)
o Metals (zirconium,
3D-printed steels)
o Coolants (liquid flibe
salt, lead bismuth)
New fuels
o Annular
o Zirconium hydride
o ...
33
Our Research

34. 34
Fusion Power!
Fusion could produce even more power with
less fuel
But it is very hard
Still ~30 years away

35. 35
Thank You!