1. IOT POLY ENGINEERING
3-3
28 March 11
DRILL
Bring your protractor and compass to class Monday (you should always bring them to class)
Study for Wednesday Quiz on fossil fuels

2. Topic 1 Energy Sources – Fuels
IOT POLY ENGINEERING
3-3
QUIZ REVIEW
Topic 1 Energy Sources – Fuels
What are the fossil fuels?
What makes them non-renewable?
Explain the formation of Coal, Natural Gas, and Petroleum.
What are the methods of extraction for fossil fuels?
What are the three locations of natural gas?
What are hydrocarbons? What is methane formula?
What is mercaptan and why is it used?

3. Topic 1 Energy Sources – Fuels
IOT POLY ENGINEERING
3-3
QUIZ REVIEW
Topic 1 Energy Sources – Fuels
Explain the operation of a seismic survey.
Who are world top producers of natural gas?
How are oil and natural gas transported?
Why are fossil fuels processed prior to use?
How is natural gas used in the home?
What’s the difference between petroleum reservoirs and reserves?
What geographic region has largest oil reserves?

4. Topic 1 Energy Sources – Fuels
IOT POLY ENGINEERING
3-3
QUIZ REVIEW
Topic 1 Energy Sources – Fuels
What 2 countries have the largest oil reserves?
How many gallons are in a barrel of oil?
How is a barrel of oil broken down in terms of end use?
Is crude oil always same color/viscosity?
What is distillation? Which fossil fuel is processed by it?
Continent consuming greatest per capita oil?

5. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nucleus of a heavy element (e.g. Uranium) splits when bombarded by a free neutron
Two smaller atoms [usually Strontium (Sr) and Xenon (Xe)], neutrons, plus energy
Extra neutrons lead to chain reaction:

6. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle
Like coal, natural gas, and petroleum, Uranium (U) is an energy source that must be processed before use.
Front End: preparing the fuel
Service Period: using fuel in reactor
Back End: safely manage, contain, reprocess/dispose of spent fuel

7. Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Front End
Exploration:
U is 500 times more abundant than gold
Traces can be found everywhere – all rocks and soils, rivers and oceans, food and human tissue
Mining and Milling:
Mining – surface (strip) or underground mining
Milling – grind up ore, use sulfuric acid to separate U from waste rock – “yellow cake” U3O8
Conversion: U must be converted into a gas before it can be enriched (uranium hexafluoride – UF6 )

8. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Front End
Uranium Ore
UF6
Yellow Cake

9. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Nuclear Fuel Cycle – Front End

10. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Front End
Background Chemistry
The number of protons are the atomic number.
Uranium’s atomic number is 92
Atoms with different numbers of neutrons are called isotopes – “same place”
Isotope U-235 is the only fissile isotope found in nature

11. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Front End
Enrichment: increase concentration of U-235 and remove 85% of U-238
Depleted Uranium: removed U-238, which includes .25% U-235, is used in metal to form yacht keels, radiation shielding, and (controversially) weapons as ammunition.
Keel

12. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Front End
Fuel Fabrication:
UF6 converted to UO2 powder
Powder converted to pellets
Pellets stacked in tubes
These are nuclear fuel rods
Groups of rods make up fuel assembly
Hundreds of assemblies make up reactor core

13. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Radioactivity
Alpha particles
Do not penetrate skin
Harmful if inhaled/ingested
Beta particles
Damage living cells, permanent nucleic change
Ovaries/testes – damage passed to future generations
Gamma rays
As damaging as X-ray
Causes mutation / cancer

14. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle
Front End: preparing the fuel
Exploration
Mining and Milling
Conversion
Enrichment
Fabrication
Service Period: using fuel in reactor
Back End: safely manage, contain, reprocess/dispose of spent fuel

15. Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Service Period
27% Recycling

16. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Service Period
Electricity Generation
Transport of radioactive materials
In-core fuel management
Old fuel rods must be changed periodically (1/3 at a time)
Food and Agriculture
FDA approved irradiation of food
Kills bacteria, insects, and parasites

17. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Service Period
Nuclear medicine – Imaging
Most medical imaging is anatomical – deals only with structures
Nuclear imaging shows physiological functioning of organs
Radiotracer injected into blood, inhaled, or ingested
“Gamma camera” detects energy given off
(PET scan – Positron Emission Tomography)

18. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Nuclear Fuel Cycle – Service Period
Nuclear weapons
Only two known uses of nuclear weapons use – Hiroshima and Nagasaki during WW2
“Little Boy”
“Fat Man”

19. Nuclear Fuel Cycle – Service Period

20. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle
Front End: preparing the fuel
Exploration
Mining and Milling
Conversion
Enrichment
Fabrication
Service Period: using fuel in reactor
Electricity, Medicine, Food and Agriculture, Military
Back End: safely manage, contain, reprocess/dispose of spent fuel

21. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Back End
Two options for spent fuel:
Interim storage and final disposal
Reprocessing to recover usable portion
Interim Storage:
Used fuel assemblies: hot and highly radioactive
Stored in special ponds usually near reactor site
Water is radiation barrier and cools fuel

22. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Back End
Reprocessing
Reprocessing separates U and Pu from waste products – chop up fuel rods and dissolve them in acid to separate materials
U enrichment
Spent fuel contains ~96% of original U
U-235 reduced to 1%
Therefore, send back to enrichment
Plutonium (Pu)
Spent fuel contains ~1% radioactive Pu
Can be blended with enriched U for new fuel
One of the most highly toxic elements known

23. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Back End
Waste
Low-level waste – radioactive isotopes decay years
Material used to handle highly radioactive parts of reactor
Cooling water pipes, radiation suits
Waste from medical uses
Processing nuclear fuel generates depleted uranium (DU)
DU used as heavy metal
High-level waste – radioactive isotopes decay >100,000 years
Material from core of reactor/decommissioned weapons

24. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Back End
Waste Disposal
Low-level waste – radioactive isotopes decay years
Temporary storage
Standard disposal methods or reuse (heavy metal)
High-level waste – radioactive isotopes decay >100,000 years
Currently only short-term storage exists
Geologic disposal. Requires:
Absolutely stable geological formations
Unprecedented stability of human institutions

25. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Back End
Waste Disposal
High-level waste – radioactive isotopes decay >100,000 years
Yucca Mountain
80 miles northwest of Las Vegas
Only proposed site in U.S. for high-level waste storage
77,000 tons capacity

26. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Back End
Waste Disposal
High-level waste – radioactive isotopes decay >100,000 years
Space Disposal
Limited capacity on rockets
Rocket malfunction is possible

27. Non-Renewable Fuels – Nuclear
IOT POLY ENGINEERING
3-3
Non-Renewable Fuels – Nuclear