Download presentation
Presentation is loading. Please wait.
2
Are you prepared?... http://www.youtube.com/watch?v=vZAJbJc1aychttp://www.youtube.com/watch?v=vZAJbJc1ayc start 2:27
4
Renewable or Non-Renewable?
5
Uranium 92 U 238.02891 6 C Carbon 12.011 How many protons? How many electrons? How many neutrons? 92 protons 92 electrons 146 neutrons What is Radiation?
6
Radiation = particles given off by unstable atoms. 3 Types: –Alpha ( α) Travels few inches Blocked by paper (skin) –Beta ( β) Travels few feet Blocked by aluminum, glass –Gamma ( γ) Travels far Blocked by lead (steel & concrete).
7
Background Radiation The amount of radiation we are exposed to daily from the environment Average = 360 millirem/year or 3 millisieverts
8
www.geology.fau.edu/course_info/fall02/ EVR3019/Nuclear_Waste.ppt
9
Genetic damages: from mutations that alter genes defects can become apparent in the next generation Somatic damages: to tissue, such as burns, miscarriages & cancers Effects of Radiation www.bio.miami.edu/beck/esc101/Chapter14&15.pp t
11
Nuclear waste Power plants produce radioactive wastes –mostly spent fuel rods (3-4 years) –each reactor produces about 20-30 tons yearly Currently stored in pools on site and then above ground casks –some remain dangerous for tens of thousands of years How should we store this waste?
14
Yucca Mountain
15
Options for Waste –Keep onsight –Bury –Shoot into space –Bury in ocean floor –Bury in Antarctica –Change it into harmless or reprocess to make new fuel
16
Low-Level & High Level Radioactive Waste Emit small amounts of ionizing radiation Stored 100-500 years 1940 1970: put in steel drums, dumped in ocean (still UK & Pakistan) 1970+: gov’t run landfills Stored for thousands of years Mostly spent fuel rods (240,000 yrs) Safety debate Options: –Keep onsight –Bury –Shoot into space –Bury in ocean floor –Bury in Antarctica –Change it into harmless
17
www.bio.miami.edu/beck/esc101/Chapter14&15.ppt
18
Nuclear Energy The energy that exists within the nucleus of an atom. Nuclear Fission = the release of energy from the splitting of atoms! Nuclear Fusion = the combining of two smaller atoms into one larger atom. http://videos.howstuffworks.com/discovery/29389-assignment-discovery-nuclear-basics-video.htm
19
Nuclear Fission http://www.youtube.com/watch?v=Pmy5fivI_4U
20
Nuclear Fusion
21
Nulear Change Nuclear Fission Bombs & power plants Big, unstable isotopes are struck by neutrons, which splits the isotope’s nuclei More neutrons “shoot out” to strike nearby isotopes, causing a chain reaction. Nuclear Fusion Sun and stars, some weapons 2 small (light) isotopes are forced together –H + H = He Need temps > 100,000,000 º C Releases more E than fission
22
437 commercial reactors in 32 countries, producing 17% electricity
24
Nuclear Power Plant 1.a controlled nuclear fission chain reaction 2.heats water 3.produce high-pressure steam 4.that turns turbines 5.which turns generator and creates electricity. http://www.howstuffworks.com/nuclear-power2.htm
25
Controlled Nuclear Fission Reaction
26
www.bio.miami.edu/beck/esc101/Chapter14&15.pp t http://www.animatedsoftware.co m/environm/nukequiz/nukequiz_ one/nuke_parts/reactor_parts.s wfhttp://www.animatedsoftware.co m/environm/nukequiz/nukequiz_ one/nuke_parts/reactor_parts.s wf
27
Boiling Water Reactor
28
Pressurized Water Reactor Boiling Water Reactor
29
http://www.ida.liu.se/~her/npp/demo.html
30
Nuclear Reactor Where nuclear fission occurs. Surrounded by thick concrete, steel & lead. Blocks all radiation!
31
Inside the Reactor Fuel Rods –35,000 – 70,000 fuel rods –3% Uranium-235 pellets –In water (moderator) Control Rods –absorb extra neutrons –Control the chain reaction http://online.wsj.com/article/SB10001424052748704396504576205000098975380. html#project%3DFUELASSEMBLY0317%26articleTabs%3Dinteractive
32
Cooling Tower Water is the coolant in the system. Tower is used to condense hot steam to liquid water. Usually taken from river, lake, ocean. Water can be reused.
33
Decommissioning Life span of a power plant = 15-40 years –Parts wear out, Fuel is spent –Plant is shut down Highly radioactive for 240,000 years Must store for 10 times the half-life –What can we do with them?
34
= time needed for one-half of the nuclei in a radioisotope to decay and emit their radiation to form a stable isotope Half-timeemitted Uranium 235710 million yrsalpha, gamma Plutonium 23924,000 yrsalpha, gamma Half-Life www.bio.miami.edu/beck/esc101/Chapter14&15.pp t
35
When people think about nuclear power they think about… 1.Effects of radiation 2.Nuclear waste disposal 3.Nuclear disasters
36
Three Mile Island - 1979.008 sieverts over 7 days Remember 1,000 sieverts is radiation sickness 5,000 is death http://maps.google.com/maps?um=1&hl=en&q=three%20mile%20island%20plant %20map&ndsp=20&safe=on&ie=UTF-8&sa=N&tab=il
37
Chernobyl - 1986 300 sieverts per hour 240 acute radiation sickness; 31 died within 3 months 100,000 people evacuated Some claim up to 985,000 deaths due to Chernobyl
38
Chernobyl Fallout
39
Japan 0.4 sieverts per hour 70,000 people evacuated 140,000 told to stay inside
40
http://streaming.discoveryeducation.com/s earch/assetDetail.cfm?guidAssetID=BE0F B49C-7C70-4C56-95F2-B3904BC9077Fhttp://streaming.discoveryeducation.com/s earch/assetDetail.cfm?guidAssetID=BE0F B49C-7C70-4C56-95F2-B3904BC9077F 10 min video on nuclear energy –Fission, fusion, overview
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.