iot poly engineering 3-3 drill february 3, 2011 copy tonight’s homework: 1.impacts journal #1 due...
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IOT
POLY ENGINEERING3-3
DRILL
February 3, 2011
Copy tonight’s homework:
1. Impacts Journal #1 due Monday.2. Bring your protractor and compass to class
Monday (you should always bring them to class)3. Study for Friday Quiz on fossil fuels
IOT
POLY ENGINEERING3-3
1. What are the fossil fuels?2. What makes them non-renewable?3. Explain the formation of Coal, Natural Gas, and Petroleum.4. What are the methods of extraction for fossil fuels?5. What are the three locations of natural gas?6. What are hydrocarbons? What is methane formula?7. What is mercaptan and why is it used?
Topic 1 Energy Sources – Fuels
QUIZ REVIEW
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POLY ENGINEERING3-3
8. Explain the operation of a seismic survey.9. Who are world top producers of natural gas?10. How are oil and natural gas transported?11. Why are fossil fuels processed prior to use?12. How is natural gas used in the home?13. What’s the difference between petroleum reservoirs and
reserves?14. What geographic region has largest oil reserves?
Topic 1 Energy Sources – Fuels
QUIZ REVIEW
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POLY ENGINEERING3-3
15. What 2 countries have the largest oil reserves?16. How many gallons are in a barrel of oil?17. How is a barrel of oil broken down in terms of end use?18. Is crude oil always same color/viscosity?19. What is distillation? Which fossil fuel is processed by it?20. Continent consuming greatest per capita oil?
Topic 1 Energy Sources – Fuels
QUIZ REVIEW
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POLY ENGINEERING3-3
Non-Renewable Fuels – Nuclear
1. Nucleus of a heavy element (e.g. Uranium) splits when bombarded by a free neutron
2. Two smaller atoms, 1-3 neutrons, plus energy3. Extra neutrons lead to chain reaction:
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POLY ENGINEERING3-3
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
Non-Renewable Fuels – NuclearNuclear Fuel Cycle – Front End
1. Exploration:1) U is 500 times more abundant than gold2) Traces can be found everywhere – all rocks and
soils, rivers and oceans, food and human tissue2. Mining and Milling:
1) Mining – surface (strip) or underground mining2) Milling – grind up ore, use sulfuric acid to separate
U from waste rock – “yellow cake” U3O8
3. Conversion: U must be converted into a gas before it can be enriched (uranium hexafluoride – UF6 )
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POLY ENGINEERING3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Front End
Uranium Ore
Yellow Cake
UF6
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POLY ENGINEERING3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Front End
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POLY ENGINEERING3-3
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
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POLY ENGINEERING3-3
Non-Renewable Fuels – NuclearNuclear Fuel Cycle – Front End
4. Enrichment: increase concentration of U-235 and remove 85% of U-238Depleted 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
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POLY ENGINEERING3-3
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Front End
5. Fuel Fabrication:1) UF6 converted to UO2 powder
2) Powder converted to pellets3) Pellets stacked in tubes4) These are nuclear fuel rods5) Groups of rods make up fuel assembly6) Hundreds of assemblies make up reactor core
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POLY ENGINEERING3-3
Non-Renewable Fuels – Nuclear
Radioactivity
1. Alpha particlesDo not penetrate skinHarmful is inhaled/ingested
2. Beta particlesDamage living cells, permanent nucleic changeOvaries/testes – damage passed to future generations
3. Gamma raysAs damaging as X-rayCauses mutation / cancer
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POLY ENGINEERING3-3
Non-Renewable Fuels – NuclearNuclear Fuel Cycle
• Front End: preparing the fuel1. Exploration2. Mining and Milling3. Conversion4. Enrichment 5. Fabrication
• Service Period: using fuel in reactor • Back End: safely manage, contain, reprocess/dispose
of spent fuel
Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Service Period
27% Recycling
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POLY ENGINEERING3-3
Non-Renewable Fuels – NuclearNuclear Fuel Cycle – Service Period
1. Electricity Generation1) Transport of radioactive materials2) In-core fuel management
Old fuel rods must be changed periodically (1/3 at a time)
2. Food and Agriculture1) FDA approved irradiation of food2) Kills bacteria, insects, and parasites
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POLY ENGINEERING3-3
Non-Renewable Fuels – NuclearNuclear Fuel Cycle – Service Period
3. Nuclear medicine – Imaging1) Most medical imaging is anatomical – deals only
with structures2) Nuclear imaging shows physiological functioning
of organs3) Radiotracer injected into blood, inhaled, or
ingested4) “Gamma camera” detects energy given off
(PET scan – Positron Emission Tomography)
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Non-Renewable Fuels – Nuclear
3. Nuclear weapons1) Only two known uses of
nuclear weapons use – Hiroshima and Nagasaki during WW2
Nuclear Fuel Cycle – Service Period
“Fat Man” “Little Boy”
Nuclear Fuel Cycle – Service Period
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Non-Renewable Fuels – NuclearNuclear Fuel Cycle
• Front End: preparing the fuel1. Exploration2. Mining and Milling3. Conversion4. Enrichment 5. Fabrication
• Service Period: using fuel in reactor Electricity, Medicine, Food and Agriculture, Military
• Back End: safely manage, contain, reprocess/dispose of spent fuel
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POLY ENGINEERING3-3
Non-Renewable Fuels – NuclearNuclear Fuel Cycle – Back End
Two options for spent fuel: • Interim storage and final disposal• Reprocessing to recover usable portion
1. Interim Storage:1) Used fuel assemblies: hot and highly radioactive2) Stored in special ponds usually near reactor site3) Water is radiation barrier and cools fuel
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Non-Renewable Fuels – NuclearNuclear Fuel Cycle – Back End
2. Reprocessing Reprocessing separates U and Pu from waste products – chop up fuel rods and dissolve them in acid to separate materials
1) U enrichmenta) Spent fuel contains ~96% of original Ub) U-235 reduced to 1%c) Therefore, send back to enrichment
2) Plutonium (Pu)a) Spent fuel contains ~1% radioactive Pub) Can be blended with enriched U for new fuelc) One of the most highly toxic elements known
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POLY ENGINEERING3-3
Non-Renewable Fuels – NuclearNuclear Fuel Cycle – Back End
Waste1. Low-level waste – radioactive isotopes decay 10-50 years
1. Material used to handle highly radioactive parts of reactorCooling water pipes, radiation suits
2. Waste from medical uses3. Processing nuclear fuel generates depleted uranium (DU)
DU used as heavy metal2. High-level waste – radioactive isotopes decay >100,000 years
Material from core of reactor/decommissioned weapons
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Non-Renewable Fuels – NuclearNuclear Fuel Cycle – Back End
Waste Disposal1. Low-level waste – radioactive isotopes decay 10-50 years
1. Temporary storage2. Standard disposal methods or reuse (heavy metal)
2. High-level waste – radioactive isotopes decay >100,000 years1. Currently only short-term storage exists2. Geologic disposal. Requires:
1. Absolutely stable geological formations2. Unprecedented stability of human institutions
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Non-Renewable Fuels – NuclearNuclear Fuel Cycle – Back End
Waste Disposal2. 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
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Non-Renewable Fuels – Nuclear
Nuclear Fuel Cycle – Back EndWaste Disposal
2. High-level waste – radioactive isotopes decay >100,000 yearsSpace Disposal
1. Limited capacity on rockets2. Rocket malfunction is possible
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POLY ENGINEERING3-3
Non-Renewable Fuels – Nuclear