1 / 30

Nuclear Reactions: The Release of Energy Through Fission

This text discusses nuclear reactions, including fission and fusion, and how they release energy. It also covers the concept of half-life, the generation of nuclear energy, and the issue of nuclear waste. Additionally, it explores concerns about nuclear power plant safety and radiation.

danielfletcher
Télécharger la présentation

Nuclear Reactions: The Release of Energy Through Fission

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Nuclear Reactions Heavy hydrogen Masses are not quite equal on both sides. The difference is ENERGY. e = mc2 Natural “spall-off” Th U mass energy + Energy + Energy From Hinrichs, 1992, Energy. Natural radioactive elements constantly break down and release energy – all around us. Forms of Radiation Fission-induced processes occur in a reactor. Controlled, imposed.

  2. Meaning of Half-Life of a Radioactive Element The longer the half-life of a radioactive element, the longer we have to worry about the radiation it is emitting. Slow rate of decay long half-life Fast rate of decay short half-life

  3. Why is the generation of nuclear energy so different from the burning of fossil fuel?

  4. Why Energy is Released from Fission: Our Gain Fusion: join to form larger pieces Fission: Break apart into smaller pieces Direction in which to gain energy. From Hinrichs, 1992, Energy. Natural disintegration vs. induced fission. Why bother with fission?

  5. How We Get “Nuclear Energy” Bring in the neutrons + Energy 235U vs. 238U + Energy Get a chain reaction going From Hinrichs, 1992, Energy.

  6. Why Anyone Would Want to Consider Nuclear Energy From Hinrichs, 1992, Energy. 35 tons of uranium dioxide (UO2) fuel produces 1000 MWe electricity. This can be done with 1 nuclear fuel shipment per year compared to 1 trainload of coal per day in a power plant.

  7. Another heat exchanger; heated water goes into river, etc.

  8. Concept of “passive safety”

  9. The Issue of Nuclear Waste Start here http://www.world-nuclear.org/info/inf03.html

  10. Radon Problems and Mitigation CVS4, Fig. 4.C Radon gas forms in soil through radioactive decayof naturally occurring uranium and thorium RADON ENTERS HOMES THROUGH: Cracks in solid floors; soil Construction joints Cracks in walls Gaps in suspended floors Gaps around service pipes Cavities inside walls The water supply A suction-based removal system can be installed to vent radon before it enters a home’s basement. http://www.epa.gov/radon/pubs/citguide.html

  11. Sources of Uranium in the US x Chemical affinity of uranium for certain geologic environments and certain other elements causes its selective enrichment. Text, Fig. 6.14

  12. http://www.chemistry.mcmaster.ca/emslie/20%20emslie%20Th%20U%20info%20v2.htmhttp://www.chemistry.mcmaster.ca/emslie/20%20emslie%20Th%20U%20info%20v2.htm

  13. Concerns about Nuclear Power Plant Safety Three Mile Island, near Harrisburg, PA, 1979: Meltdown, but hardly any release of radioactivity Huge loss in public confidence, however Chernobyl, Ukraine, 1986 (Box 6.2, Fig. 6.9): Meltdown. 10% of core’s material lofted into atmosphere Terrible impact all over Europe and beyond (see Fig. 6.9 map) Fukushima, Japan (March, 2011): Earthquake hit; reactors shut down Tsunami interrupted electrical power and thus, cooling; caused reactors to overheat 3 reactors ultimately underwent meltdown

  14. Fukushima Daiichi Nuclear Disaster in Japan in March, 2011 Boiling water reactors Earthquake hit; reactors shut down Tsunami interrupted electricity for cooling; caused reactors to overheat 3 reactors ultimately underwent meltdown

  15. Concerns about Radiation http://www.radon.com/radon/radon_EPA.html See opinion pieces: 2011 Scientific American, 2012 Wall Street Journal

  16. Uranium Decay Series Steps in the Radioactive Decay of Uranium to Lead Radon From http://en.wikipedia.org/wiki/Radon

  17. Annual Energy Outlook, 2015, EIA

More Related