Nuclear Energy Can we reach for a sustainable and attainable energy Future?

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1 Energy and Society

2 Nuclear Energy Can we reach for a sustainable and attainable energy Future? Chapter 7 + handouts Thursday September 27, 2012

3 OECD countries The mission of the Organization for Economic Co-operation and Development (OECD) is to promote policies that will improve the economic and social well-being of people around the world. Assignment for Tuesday Oct. 2, 2012

5 Nuclear Power or Nuclear Energy Worldwide Excitement about Nuclear Science

6 As a zero-carbon energy source, nuclear power must be part of our energy mix as we work toward energy independence and meeting the challenge of global warming. Nobel physicist Steven Chu, U.S. Secretary of Energy - May 6, 2009

7 Complicated Related to Nuclear Weapons. Atoms for Peace program Fear/Emotion Lack of understanding/knowledge Expensive Radioactive Waste

9 "Atoms for Peace" was the title of a speech delivered by U.S. President Dwight D. Eisenhower to the UN General Assembly in New York City on December 8, "It is with the book of history, and not with isolated pages, that the United States will ever wish to be identified. My country wants to be constructive, not destructive. It wants agreement, not wars, among nations. It wants itself to live in freedom, and in the confidence that the people of every other nation enjoy equally the right of choosing their own way of life." "To the making of these fateful decisions, the United States pledges before you--and therefore before the world--its determination to help solve the fearful atomic dilemma--to devote its entire heart and mind to find the way by which the miraculous inventiveness of man shall not be dedicated to his death, but consecrated to his life."

10 Isotopes for the Nation s Future Ani Aprahamian University of Notre Dame

11 Background Isotopes are vital to the science and technology base of the US economy. medicine biology physics chemistry environmental sciences material studies new resource development petrochemical, nuclear, bio-fuels homeland security Atoms for Peace program 1954 US Department of Energy..Office of Nuclear Energy

12 Isotopes used as environmental tracers. For example: As-73 is needed to understand As contamination and transport. Na-22, Sr-87, and other solute reactive isotopes are needed to understand flowpaths for geochemical and hydrologic modeling. Al-26 is needed to understand the impacts of acid rain. Si-32 is needed for oceanographic tracing, which contributes to a better understanding of climate change and its effects.

Assessments Nuclear Trafficking Proliferation Material Analysis Ion Implantation Material Structure Geology &

13 Nuclear Physics Applications Energy ADS systems Fusion confinement Nuclear Waste Nuclear Data Life Science Medical Diagnostics Medical Therapy Radiobiology Biomedical tracers Nuclear Forensics Homeland Security Risk Assessments Nuclear Trafficking Proliferation Material Analysis Ion Implantation Material Structure Geology & Climate Environment Art & Archaeology Nuclear Defense Weapon Analysis Functionality Simulation Long-Term Storage

14 Nuclear Imaging Blood flow with radiopharmaceuticals Imaging software and analysis Gamma Camera SPEC & PEP Tumor mapping & visualization by radioactive isotope accumulation. Imaging system development

15 Radiation Treatment Brachytherapy Gamma therapy Neutron therapy Heavy ion therapy

16 Fission/Fusion Reactors for the Future The Tokomak approach ITER The laser approach NIF Magnet field confined plasma fusion Laser ignition fusion

Nuclear Energy From nuclear power plants

nuclear waste management to nuclear pace

17 Nuclear Energy From nuclear power plants Accelerator Driven Systems (ADS) for operating sub-critical reactors 1GeV accelerator development (~10 15 n/s) ADS for nuclear waste management to nuclear pace makers Beam optics & irradiation system development Incineration strategies

18 Material Treatment and Analysis of Artifacts Implantation and irradiation from silicon chips to solar sails Dating real and false mummies

homeland security Nuclear Forensics Trafficking of

control & radiation exposure (instrumentation)

composition or material structure analysis Signature

19 homeland security Nuclear Forensics Trafficking of nuclear materials & material loss assessments Border control & radiation exposure (instrumentation) Provenance of radioactive material by isotope composition or material structure analysis Signature identification, Detector array development Sensitivity analysis

20 Nuclear Energy Facts Do not use Fossil Fuels Energy from fission of Uranium Or New International program ITER in France.180 country international project!! No carbon emissions to the atmosphere CO 2, SO 2, CO (what renewables??) 20% of US energy needs met by nuclear power plants most of them old! None built over 30 yrs.

21 Location of Projected New Nuclear Power Reactors

22 There are currently 104 licensed to operate nuclear power plants in the United States (69 PWRs and 35 BWRs), which generate about 20% of our nation's electrical use. Pressurized Water Reactors (PWRs) Boiling Water Reactors (BWRs)

23 . E=mc 2 Each fission releases more than 1 neutron

24 Uranium has two isotopes 235 (0.7%) and 238 (99.3%) The amount of free energy contained in nuclear fuel is millions of times the amount of free energy contained in a similar mass of chemical fuel such as gasoline, making nuclear fission a very tempting source of energy; however, the products of nuclear fission are radioactive and remain so for significant amounts of time, giving rise to a nuclear waste problem. Concerns over nuclear waste accumulation and over the destructive potential of nuclear weapons may counterbalance the desirable qualities of fission as an energy source, and give rise to ongoing political debate over nuclear power.

25 History Univ. of Chicago Enrico Fermi Manhattan Project.Oppenheimer led Atoms for Peace President Eisenhower to United Nations 1954 Atomic Energy Act

26 Periodic Table of the Elements

27 The Nuclear Chart Proton: 2 up, 1 down quark Neutron: 2 down, one up quark Gluons: quark antiquark

28 Atomic Number = number of protons Atomic Mass = number of protons + number of neutrons What is Atomic Weight? Chart of Nuclides

29 Where is the Energy coming from?????? Splitting the Uranium Atom: Uranium is the principle element used in nuclear reactors and in certain types of atomic bombs. The specific isotope used is 235 U. When a stray neutron strikes a 235 U nucleus, it is at first absorbed into it. This creates 236 U. 236 U is unstable and this causes the atom to fission. 235 U + 1 neutron 235 U + 1 neutron 2 neutrons + 92 Kr Ba + ENERGY 2 neutrons + 92 Sr Xe + ENERGY

30 Radioactivity Americium -241: Used in many smoke detectors for homes and business... Cadmium -109: Used to analyze metal alloys for checking stock, sorting scrap. Calcium - 47: Important aid to biomedical researchers studying the cell function and bone formation of mammals. Californium - 252: Used to inspect airline luggage for hidden explosives...to gauge the moisture content of soil in the road construction and building industries...and to measure the moisture of materials stored in silos. Carbon - 14: Helps in research to ensure that potential new drugs are metabolized without forming harmful by-products. Cesium - 137: Used to treat cancers... Chromium - 51: Used in research in red blood cell survival studies. Cobalt - 57: Used in nuclear medicine to help physicians interpret diagnosis scans of patients' organs, and to diagnose pernicious anemia. Cobalt - 60 : Used to sterilize surgical instruments...spices/fruits Copper - 67: cancer

31 Radioactivity Alpha decay Beta decay Electron capture Gamma Decay Half-life very short very long- longer than age of earth.billions of yrs 14 C 5730 yrs

32 Alpha Decay

33 Beta Decay

34 Gamma Decay

35 Half-lives are very often used to describe quantities undergoing exponential decay for example radioactive decay where the half-life is constant over the whole life of the decay. Number of half-lives elapsed Fraction remaining 0 1 / / / 4 25 Percentage remaining 3 1 / / / / / n 1/2 n 100(1/2 n )

36 A quantity is said to be subject to exponential decay if it decreases at a rate proportional to its value. Symbolically, this can be expressed as the following differential equation, where N is the quantity and λ is a positive number called the decay constant. The solution to this equation is: Here N(t) is the quantity at time t, and N 0 = N(0) is the initial quantity, i.e. the quantity at time t = 0.

37 . Half-life:time required for the decaying quantity to fall to one half of its initial value This time is called the half-life, and often denoted by the symbol t 1 / 2. The half-life can be written in terms of the decay constant, or the mean lifetime, as: Example: 14 C /5730 yrs =1.21 x10-4 /yr or l=ln2/t 1/2 Example: How old is an object whose 14C content is 10% of what it is in living organisms today?

38 Environmental and safety aspects of nuclear energy Not in My Back Yucca What are our alternatives for storing radioactive waste? By Brendan I. Koerner Posted Tuesday, April 15, 2008, at 8:11 AM ET Environmental Statement on Nuclear Energy and Global Warming June 2005 Too expensive power plants Too dangerous- terrorist groups Too polluting- radioactive waste

39 Thorium: Is It the Better Nuclear Fuel? What is special about thorium? (1) Weapons-grade fissionable material (uranium 233 ) is harder to retrieve safely and clandestinely from the thorium reactor than plutonium is from the uranium breeder reactor. (2) Thorium produces 10 to 10,000 times less long-lived radioactive waste than uranium or plutonium reactors. (3) Thorium comes out of the ground as a 100% pure, usable isotope, which does not require enrichment, whereas natural uranium contains only 0.7% fissionable U 235. (4) Because thorium does not sustain chain reaction, fission stops by default if we stop priming it, and a runaway chain reaction accident is improbable.

40 Here is the thorium sequence in the Rubbia reactor: A neutron is captured by 90Th 232, which makes it 90 Th Th n 1 -> 90Th 233 [1] Thorium-233 spontaneously emits a beta particle (an electron from the nucleus, see p 173), leaving behind one additional proton, and one fewer neutron. ("...Nuclear Energy" p134) This is called "beta decay." 90Th 233 -> 91Pa ß [2] The element with 91 protons is Protactinium (Pa). The isotope 91 PA 233 also undergoes beta decay, 91Pa 233 -> 92U ß [3] The U 233 isotope that is produced in step [3] is fissionable, but has fewer neutrons than its heavier cousin, Uranium-235, and its fission releases only 2 neutrons, not 3. 92U n 1 -> fission fragments n 1 [4]

Fusion Energy (how the sun gets its energy) In a fusion reaction, two light atomic nuclei fuse together to form heavier ones, as is shown in the figure.

41 Fusion Energy (how the sun gets its energy) In a fusion reaction, two light atomic nuclei fuse together to form heavier ones, as is shown in the figure. The fusion process releases a large amount of energy, which is the energy source of the sun and the stars. Proton + neutron=deuterium Proton + 2 neutrons=tritium

42 D+ T= 4 He +n MeV 2 H+ 3 H= 4 He

43 Fusion energy

44 Fusion Inside the Stars Fusion in the core of stars is reached when the density and temperature are high enough. There are different fusion cycles that occur in different phases of the life of a star. These different cycles make the different elements we know. The first fusion cycle is the fusion of hydrogen into Helium. This is the stage that our Sun is in.

45 The long-term objective of fusion research is to harness the nuclear energy provided by the fusion of light atoms to help meet mankind s future energy needs.

Nuclear Physics Applications in industry, medicine, and liberal arts

Nuclear Physics Applications in industry, medicine, and liberal arts Energy Sources Nuclear Forensics Homeland Security Imaging and Diagnostics Radiation Treatment Material Science Art and Archaeology