Lecture 3-1-40: Evaluative Methods for Nuclear Non-proliferation and Security PDF

NUCE 304: Evaluative Methods for Nuclear Non-proliferation and Security Energy, Power, Nuclear Technology, Elementary Particles, and Radioactivity Dr. Ahmed Alkaabi 1 Learning Objectives Nuclear and Reactor Physics...

NUCE 304: Evaluative Methods for Nuclear Non-proliferation and Security Energy, Power, Nuclear Technology, Elementary Particles, and Radioactivity Dr. Ahmed Alkaabi 1 Learning Objectives Nuclear and Reactor Physics Be able to explain how nuclear power produces electrical power Be able to explain how and why nuclear power works Be able to explain why fission products and radiation are major issues for nuclear power Be able to explain the role of neutron interactions in nuclear power 2 Today’s Primary Learning Objective Be able to explain how nuclear energy produces electrical energy Understand radioactivity Understand why nuclear power works Take away from these lectures: Nuclear reactions generate thermal energy which can be used to create steam to drive a turbine-generator to produce electricity. Nuclear power is unique, requiring special attention to Safety, Security, and Safeguards. Nuclear physics underpins all aspects of nuclear power and nuclear applications in general 3  Energy and Power (The amount of fuel contained within Energy is the ability to do work something or consumed by something within a given time period) Power is the rate at which work is done (Energy flow per unit time) What is “work”? 1. Moving something against a force, or 2. Changing the temperature of something. Energy must be consumed to get work done Electrical Energy Chemical Energy Wind Energy 4  Units for Energy and Power Energy is the ability to do work Energy = Power x Time 1 Joule = 1 Kg-m2/sec2 ~ the amount of energy needed to move a small apple (102 gms) 1 meter straight up 1 AA alkaline battery stores about 9,000 Joules Power is the rate at which work is done Power = Energy / Time 1 Watt = 1 Joule/second 1 Kilowatt = 1,000 Joules/second = 1.0 x 103 Joules/second ~ 1 Kilowatt 60 Watt bulbs 5  Energy Units 1 Watt = 1 Joule/sec Power = Energy / Time 1 Watt-sec = 1 Joule Energy = Power x Time 1 kW-sec = 1,000 Joules = 103 Joules 1 kW-hr = 3,600 x 103 Joules = 3.6 x 106 Joules = 3.6 MJ gasoline ~10 kW-hrs per liter Operating the toaster or 100 ml of gasoline ~ 1 Kilowatt the hair dryer for 1 hour contains 1 kW-hr consumes 1 kW-hr of of chemical energy electrical energy Baseball traveling 90 mph contains ~118 Joules of Kinetic Energy = ½ mv2 Kinetic energy, or 6 3.28 x 10-5 kW-hrs 6  Energy Basics Energy = The ability to do work The Law of Conservation of Energy: “Energy can neither be created or destroyed.” We cannot “create” electrical energy. We must convert one type of existing energy into electrical energy Common Types of Energy: ❑ Potential Energy ❑ Thermal Energy ❑ Kinetic or Mechanical Energy ❑ Electrical Energy 7 How do We Generate Electric Power? N S http://www.generatorguide.net/howgeneratorworks.html © Walter Fendt, May 8, 1998 © Dept. of Physics, The Chinese University of Hong Kong Source: www. hk-phy.org Reproduced with permission © Dept. of Physics, The Chinese University of Hong Kong Source: www. hk-phy.org Reproduced with permission 8  Generating Electricity From Water Power Source: US Bureau of Reclamation Potential Energy → Kinetic/Mechanical Energy → Electrical Energy Hydroelectric Power Generation Source: US Nuclear Regulatory Commission 9  Generating Electricity From Wind Power Source: US Department of Energy Wind (Kinetic) Energy → Mechanical Energy → Electrical Energy 10  Generating Electricity Using Photovoltaics Solar Energy → Electrical Energy Source: solarenergyfactsblog.com 11  Concentrating Solar Power Plant 1. Sunlight is concentrated and directed from a large field of heliostats (mirrors) to a receiver on a tall tower. 2. Molten salt from a cold salt tank is pumped through the receiver, where it is heated to 1050°F (566°C). 3. The heated salt from the receiver is stored in a hot salt tank. 4. Molten salt is pumped from the hot salt tank through a steam drum that creates steam to drive a steam turbine and generate electricity. 5. Cold salt (525°F/288°C) flows back to the cold salt tank to be re-used. Source: US DOE/EERE (www.eere.energy.gov) Solar Energy → Thermal Energy → Kinetic Energy → Mechanical Energy → Electrical Energy Source: Sandia National Labs 12  Hydro provides about 17-percent of world electricity. Very limited growth potential. Solar Photo Voltaic and Wind are part of “Others,” 5-percent. Both are growing, but they are not useful for baseload. How do we get electricity from fossil fuels and nuclear? 13 Rankine Cycle 1. The Rankine cycle converts heat (thermal energy) into mechanical energy, which we then convert to electrical energy by using the turbine shaft to drive a generator. 2. The heat is supplied externally to a closed loop containing the “working fluid” (usually water). 3. The Rankine cycle generates about 80% of all electric power used throughout the world, including virtually all solar thermal, biomass, coal, and nuclear power plants. 4. The Rankine cycle is the fundamental thermodynamic underpinning of the steam engine. 5. It is named after William John Macquorn Rankine, a Scottish polymath. Source: Wikipedia 14  Rankine Cycle Process Steps Process 1-2: Working fluid pumped from low to high pressure. As the fluid is a liquid at this stage, the pump requires little input energy. Process 2-3: High pressure liquid enters a boiler where it is heated at constant pressure by an external heat source to become a dry saturated vapor. Source: Andrew.Ainsworth at the English Wikipedia project Process 3-4: Dry saturated vapor expands through a turbine, generating power. This expansion process decreases the temperature and pressure of the vapor, and some condensation may occur. Process 4-1: Wet vapor then enters a condenser where it is condensed at a constant pressure to become a saturated liquid. 15  Thermodynamic Efficiency η = Thermodynamic Efficiency = Net Work Out Heat Added THOT − TCOLD “Carnot Cycle” -- ηc = THOT Note-1: Temps are “Absolute”: T (Absolute) = T (Centigrade) + 273⁰ Note-2: Carnot cycle is “ideal.” Others (e.g., Rankine) are less efficient. Example: Modern Coal-fired Power Plant THOT − TCOLD (350 + 273) − (50 + 273) ηc = = = 48% THOT 350 +273 16 Fossil Fuel Steam Power Plant Water is converted into steam Chemical Energy → Thermal Energy → Kinetic Energy → Mechanical Energy → Source: "Nuclear Reactor Concepts" Workshop Manual, U.S. NRC http://www.nrc.gov/reading-rm/basic-ref/teachers/unit3.html Electrical Energy 17 Nuclear Fueled Steam Plant Nuclear Energy → Kinetic Energy → Thermal Energy → Kinetic Energy → Mechanical Energy → Electrical Energy Fossil Fueled Steam Plant Nuclear Fueled Steam Plant Source: "Nuclear Reactor Concepts" Workshop Manual, U.S. NRC http://www.nrc.gov/reading-rm/basic-ref/teachers/unit3.html 18  Nuclear Fission Energy (E = mc2) Uranium in nature Fissioning 1 kg. U-235 Equivalent to Burning 99.3 percent U-238 3,000 tons Coal 0.72 percent U-235 19  Where the Thermal Energy (Heat) Comes From UO2 fuel pellet. Enriched to 3-5 percent U-235 20  Sample of Chart (Table) of Nuclides – available in hard copy or electronic versions on the internet Z 94 93 92 91 N U-235 and U-238 are two of the isotopes of interest in nuclear fuel cycle 21  World Nuclear Energy Production http://www.iaea.org/PRIS/WorldStatistics/WorldTrendi nElectricalProduction.aspx 22  Current Status of World Nuclear Power http://www.iaea.org/PRIS/WorldStatistics/Oper 23 ationalReactorsByCountry.aspx  Power Reactors Under Construction http://www.iaea.org/PRIS/WorldStatistics/UnderConstru ctionReactorsByCountry.aspx 24  Future Nuclear Plans NUCLEAR POWER REACTORS 71 UNDER CONSTRUCTION MWe TOTAL NET TO BE INSTALLED 74,997 CAPACITY NUCLEAR POWER REACTORS 172 ORDERED/PLANNED NUCLEAR POWER REACTORS 312 PROPOSED http://www.world-nuclear.org/info/Facts-and-Figures/World-Nuclear- Power-Reactors-and-Uranium-Requirements/ 25  Safety, Safeguards, and Security Nuclear Power is unique among energy sources It uses fissile nuclear fuel and requires specialized nuclear technology and design knowledge It generates fission products and other highly radioactive materials It continues to generate thermal energy after you shut it down (i.e., you can’t completely turn it off) Because of these unique characteristics, Nuclear Power has a special requirement for attending to Safety, Safeguards, and Security (the 3S’s) 26  Interrelationships Between Nuclear Energy “3S” and GNEII Course Topics SECURITY Prevent sabotage and malicious acts SAFETY Prevent accidents and mitigate consequences SAFEGUARDS Prevent theft and diversion 27 28 Types of Nuclear Power Reactors Power Reactors are classified by – Neutron energy Thermal reactors: majority of neutron interactions involve thermal neutrons (energy < 1 eV) Fast reactors: majority of neutron interactions involve fast neutrons (energy > 1 MeV) – Type of moderator; Type of coolant; Type of fuel Main Types of Nuclear Power Reactors – Gas-cooled Reactors (GCRs); may be “Thermal” or “Fast” – Heavy Water Reactors (e.g., Canadian Deuterium- Uranium Reactor (CANDU)) – Light Water Reactors (LWRs) Pressurized Water Reactor (PWR) Boiling Water Reactor (BWR) 29  Gas-Cooled Reactor -- Magnox CO2 © Österreichisches Ökologie-Institut http://www.ecology.at/nni/index.php?p=type&t=gcr 30 Canadian Deuterium-Uranium Reactors Source: www.Nuclearfaq.ca “Heavy” Water 31 Types of Nuclear Power Reactors Power Reactors are classified by – Neutron energy Thermal reactors: majority of neutron interactions involve thermal neutrons (energy < 1 eV) Fast reactors: majority of neutron interactions involve fast neutrons (energy > 1 MeV) – Type of moderator; Type of coolant; Type of fuel Main Types of Nuclear Power Reactors – Gas-cooled Reactors (GCRs); may be “Thermal” or “Fast” – Heavy Water Reactors (e.g., Canadian Deuterium- Uranium Reactor (CANDU)) – Light Water Reactors (LWRs) Boiling Water Reactor (BWR) Pressurized Water Reactor (PWR) 32  Boiling Water Reactors (BWR) BWRs boil the water directly in the core: water is converted to steam and then recycled back into water by the condenser to be used again to remove heat from the core. 33  Pressurized Water Reactors Pressurized water heats, but does not boil Two major systems used to convert the heat into electrical power: primary system and secondary system Secondary loop Primary loop Source: NRC http://www.nrc.gov/reading-rm/basic-ref/students/animated-pwr.html 34  Pressurized Water Reactors (continued) Primary system (primary loop) transfers the heat from the fuel to the steam generator Secondary system (secondary loop) transfers the steam formed in the steam generator to the main turbine – the turbine is attached to the electrical generator Then the steam is routed to the main condenser – cool water circulates through the tubes in the condenser – the excess heat is removed and the steam condenses to water which is pumped back to the steam generator Water from the reactor and the water in the steam generator never mix – most of the radioactivity stays in the reactor area 35 Nuclear power plants in commercial operation (Source: http://www.world-nuclear.org/info/inf32.html) ** ** 270 248 84 78 47 23 17 8.8 15 10 2 0.6 GWe = capacity in thousands of megawatts (gross) Source: Nuclear Engineering International Handbook 2008 (** These two columns updated to 1 Jan 2012 from IAEA data) For reactors under construction: see paper “Plans for New Reactors Worldwide” at http://www.world-nuclear.org/info/inf17.html 36 37  Used Nuclear Fuel Storage Used fuel first stored in pool at least 5 years o Cooling and shielding Older fuel can move to dry casks o Air cools o Steel and concrete shields 38  Used Nuclear Fuel Disposal All countries that have a plan, plan for deep geologic repository Design variables o Rock type o Container o Retrievability o Saturation Major hurdles o Site selection o Site selection o Site selection! 39  Actinide Management Reduced Radiotoxicity 40