Nuclear Reactors. 3 Unit Nuclear Power Station - Coastal Bryon Nuclear Plant, Illinois. 3 Unit Nuclear Power Station - Desert

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1 3 Unit Nuclear Power Station - Desert Nuclear Reactors Homeland Security Course February 1, 2007 Tom Gesell 3 Unit Nuclear Power Station - Coastal Bryon Nuclear Plant, Illinois 1

Power Reactor Statistics (Uranium Information Centre, IAEA) The number of nuclear power plants is flat with 440 plants in 1996, 441 in 1997, 435 in 1999, 433 in 2000, 440 in 2002, and 443 in 2005

10, 2006) Other countries active in building new plants are India (8), Russia (4), China (3), Bulgaria and Ukraine (2 each), Argentina, Finland, Iran, Japan, Pakistan, and Romania (1 each) Power

2 Power Reactor Statistics (Uranium Information Centre, IAEA) The number of nuclear power plants is flat with 440 plants in 1996, 441 in 1997, 435 in 1999, 433 in 2000, 440 in 2002, and 443 in 2005 However 25 reactors (22 GWE) are being built According to Dale E. Klein, Chairman of the U.S.NRC, license applications for more than 24 U.S. reactors are expected start arriving at NRC by the end of 2007 (Health Physics News Vol 34, No. 10, 2006) Other countries active in building new plants are India (8), Russia (4), China (3), Bulgaria and Ukraine (2 each), Argentina, Finland, Iran, Japan, Pakistan, and Romania (1 each) Power Reactor Statistics 31 countries produce some nuclear electricity, up from 25 in 1990 Current world capacity is 370 GWE representing 19% of global electricity 17 countries generate more than 20% with nuclear. Highest are France (72.1%) and Lithuania (77.1%). The worldwide average is 19.28% U.S. generates 19.3%, down from 21% in 1990 In terms of numbers of reactors for largest users: US (104), France (59), Japan (56), Russia (31), UK (23), South Korea (20), Canada (18), Germany (17), India (15), Ukraine (15), Sweden (10) Worldwide Power Plant Locations North American Power Plant Locations 2

3 Nuclear Share of Electricity Generation in 2004 (IAEA) World Electricity Generation 3

Other Uses of Reactors Weapons materials production Propulsion

was the world's first large-scale plutonium production reactor.

the uranium slugs at 75,000 gallons per minute.

US and Russia Have Nuclear-powered Fleets with classified reactor

245 operating research reactors in 66 countries (IAEA) and about 150

4 Other Uses of Reactors Weapons materials production Propulsion Research Completed in September 1944, the 250,000 kilowatt B Reactor was the world's first large-scale plutonium production reactor. Two hundred tons of aluminum clad uranium slugs the size of rolls of quarters went into tubes. Cooling water from the Columbia River was pumped through tubes around the uranium slugs at 75,000 gallons per minute. This and all other US production reactors are shut down. US and Russia Have Nuclear-powered Fleets with classified reactor designs Research Reactor Statistics Worldwide there are 670 total and 245 operating research reactors in 66 countries (IAEA) and about 150 nuclear powered ships In US there are 50 licensed research and test reactors: 33 reactors operating in 22 States 17 reactors permanently shut down or under decommissioning 4

Reactor Design Basic purposes of reactors are research production propulsion electrical generation Major variations relate to fuel, moderator and coolant Reactor Design Many configurations of

5 Reactor Design Basic purposes of reactors are research production propulsion electrical generation Major variations relate to fuel, moderator and coolant Reactor Design Many configurations of reactors have been designed and tested Neutron Energy thermal or slow neutron fast neutron (breeders) Coolant gas cooled liquid cooled boiling water reactors pressurized water reactors Moderators light water heavy water graphite Fuel enrichment none slight Highly Advanced design Reactor Design 5

6 250 KW TRIGA Mark I Research Reactor Diagram Triga Research Reactor Core Advanced Test Reactor at INEEL Triga Research Reactor Core During Operation 6

7 Boiling Water Power Reactor Pressurized Water Power Reactor Reactor Components RBMK Reactor 7

exceptions Basis for the design was naval propulsion reactors Fuel is usually uranium oxide pellets in rods or pins

8 Advanced Gas-cooled Reactor (second generation British design) Pebble Bed Reactor Pebble Bed Reactor Fuel Spheres Reactor Design Today's standard power reactor is a light water reactor using slightly enriched fuel, but there are exceptions Basis for the design was naval propulsion reactors Fuel is usually uranium oxide pellets in rods or pins about 1/2 inch in diameter Cladding serves as a barrier to fission products Space is allowed for build-up of gaseous fission products 8

Reactor Kinetics Basis of fission reactor is that neutrons induce fission and fission produces neutrons Reactor is designed to permit this process to occur in a stable, controlled fashion fission

Figure 3 neutron uranium 235 uranium 236 neutrons Reactor Kinetics It is important that reactivity have a negative temperature coefficient Reactivity is adjusted by poisons control rods neutron

9 Reactor Kinetics Basis of fission reactor is that neutrons induce fission and fission produces neutrons Reactor is designed to permit this process to occur in a stable, controlled fashion fission fragments Reactor Kinetics k is the neutron multiplication factor per generation k > 1, reaction rate increases k < 1, reaction rate decreases Reactivity is another way to express reactor kinetics Figure 3 neutron uranium 235 uranium 236 neutrons Reactor Kinetics It is important that reactivity have a negative temperature coefficient Reactivity is adjusted by poisons control rods neutron absorbers in coolant As fuel ages, fission products act as poisons TRIGA control rod and drive Reactor Kinetics The rate of change of neutron flux is given by Where k is neutron multiplication factor and l is the generation time, about 10-3 s On this basis alone, reactors would be uncontrollable Control rod from Russian reactor 9

$Reactor Kinetics Fortunately there are delayed neutrons which effectively increases L If beta is the fraction of delayed neutrons, then for$ Reactor emissions and waste are mostly fission products Fission product inventories: text Figs 8-3 & 8-8 and Table 8-6 Also activation

Reactor emissions and waste are mostly fission products Fission product inventories: text Figs 8-3 & 8-8 and Table 8-6 Also activation

10 Reactor Kinetics Fortunately there are delayed neutrons which effectively increases L If beta is the fraction of delayed neutrons, then for the case Delayed neutrons control the reaction If however, What are the Emissions? Reactor emissions and waste are mostly fission products Fission product inventories: text Figs 8-3 & 8-8 and Table 8-6 Also activation products & hot particles The reaction is prompt supercritical, a condition to be avoided Fission Product Mass Number Distributions Percent of Total Beta Activity as a Function of Time After Reactor Shutdown 10

11 How Are Emissions Released? Emissions from the fuel tramp uranium diffusion and leakage from fuel failed fuel Airborne wastes (mostly gas) source is removal of gases from the operating fluids cleanup can include filtration (HEPA) charcoal trapping cryogenic trapping Liquid waste leakage Coolant cleanup Safety and Emission Barriers at Nuclear Power Plants Other Wastes Solid waste resin cores contaminated worn out parts cleaning materials disposable protective clothing Routine Emissions and Wastes Doses from routine reactor operations noble gases typically dominate dose Note that air pathway dose limits have been superseded by EPA limits has reports on reactor effluents available for downloading 11

Iodines dominate early dose Cesium-137 dominates late dose U.S.

12 Emissions from Reactor Accidents Only two accidents have resulted in large releases of radionuclides Chernobyl - 48,000,000 curies Windscale - 20,000 curies (TMI - 4 curies) Iodines dominate early dose Cesium-137 dominates late dose U.S. reactor accident probabilities have been calculated to be small even smaller for accidents with serious consequences 12

Types of Nuclear Reactors. Dr. GUVEN Professor of Aerospace Engineering Nuclear Science and Technology Engineer

Types of Nuclear Reactors. Dr. GUVEN Professor of Aerospace Engineering Nuclear Science and Technology Engineer Types of Nuclear Reactors Dr. GUVEN Professor of Aerospace Engineering Nuclear Science and Technology Engineer Types of Reactors (Fuel) As far as the type of fuels are concerned, three types of reactors