DOCSLIB.ORG

Modeling and Experiment of Fission Products Release and Interaction with Coolant For

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Modeling and Experiment of Fission Products Release and Interaction with Coolant For Modeling and experiment of fission products release and interaction with coolant for defective fuel in Light Water Reactor (LWR) Thesis Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By Sha Xue, B. S. Graduate Program in Nuclear Engineering The Ohio State University 2017 Thesis Committee: Jinsuo Zhang, Advisor Marat Khafizov, Co-advisor Copyright by Sha Xue 2017 Abstract During the normal operation of light water reactor, fuel defects can reside on fuel cladding from various reason such as fuel-pellet mechanical interaction, the hydriding of the Zr clad, the grid fritting from the assembly support, the warp wire fritting with the clad and also the stress corrosion cracking (SCC). The formation of defects on fuel cladding will result water ingression to the gap and react with nuclear fuel and the cladding inner surface. The interaction of water and nuclear fuel will affect the fuel thermal properties and deteriorate the cladding by hydriding and change of oxygen potential in the fuel. The change of fuel thermal properties will decrease the thermal conductivity, lead the decrease of heat transfer coefficient which may increase the fuel melting risk. The volatile fission products and fission gas will release to the coolant through cladding defects and increase the coolant activity and the defective nuclear fuel becomes a fission product source term when reactor is under normal operation. Experimental and modeling are applied to understand the behavior of a defective fuel pin. The experimental part focuses on the dissolution test of rare earth fission products in simulated LWR coolant chemistry and the diffusion coefficient measurement of cesium iodide in simulated LWR coolant chemistry using Nuclear Magnetic Resonance (NMR) technique. Rare earth fission products significantly contribute the residual heat and large quantity of radioactivity after the core shut down or in severe accident, therefore, their ii dissolution kinetic parameters in LWR are important to reactor safety and the understanding the source terms. The solubility test of rare earth fission product species (La2O3, Nd2O3 and CeO2) in simulate LWR coolant water (1000 ppm H3BO3 and 2 ppm LiOH) under different temperatures (room temperature 23 oC, 40 oC, 60 oC and 80 oC), results show that Neodymium oxide has the largest solubility in boric acid water and cerium oxide has the lowest solubility, the addition of boric acid will significantly increase the solubility of rare earth oxide in boric acid water. The diffusion coefficient of cesium iodide in boric acid water is measured using NMR technique. The NMR Diffusion-Ordered Spectroscopy (DOSY) measurement of Cs+ in simulated LWR coolant chemistry shows the self-diffusion coefficient of Cs+ is about 3.04 × 10-11 m2/s, and shows little dependence on Cs+ concentration in the solution. The measured data is about 100 times smaller than Cs+ in free water, different solution composition, temperature difference, pH difference and also the measurement method difference may cause the difference. The cesium transport and diffusion through the fuel matrix based on a fuel oxidation model is established. MOOSE/BISON code developed by Idaho National Laboratory is used to develop the cesium release model, the oxidation model results from the developed model agree with the results in reference which validate the model development using MOOSE/BISON. The cesium release model shows the time dependent cesium release after fuel defects reside on the fuel cladding, the radioactivity release to the coolant will be significant in the long term operation. The releasing of Cs into the coolant is significant iii when the fuel-water contact area is about 5%. And the releasing of Cs into the coolant will be significant when the diffusion coefficient of Cs in the fuel matrix increases 10 times. iv Dedication Dedicated to the students at The Ohio State University v Acknowledgments I would like to first thank Prof. Zhang to offer me an opportunity to work with him in OSU. He always passes his wisdom to me during my study and research, and supports my study. I’d like to thank Prof. Khafizov and Prof. Smidts’s help to my research and guidance. I’d like to thank Boyuan Li always helping me in life and study. I’d like to thank Yixing Shen, he offers lots of help to my academic study. Furthermore I’d like to express my gratitude to Dr. Wentao Zhou, Xiang Li, Yafei Wang, Jeremy Isler, Nik Shay, Evan Wu, Dr. Yi Xie, Dr. Shaoqiang Guo, this accomplishment would not have been possible without them. Finally, thanks all of you again, my life becomes more colorful and meaningful because your appearance in my life. vi Vita 2012……………….....................B.S. Nuclear Engineering, Xi’an Jiaotong University 2012 to 2015………………….. Research assistant in Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences 2015 to present………………… Graduate Research Associate, Nuclear Engineering Program, The Ohio State University Fields of Study Major Field: Nuclear Engineering vii Table of Contents Abstract ............................................................................................................................... ii Dedication ........................................................................................................................... v Acknowledgments.............................................................................................................. vi Vita .................................................................................................................................... vii List of Tables ...................................................................................................................... x List of Figures .................................................................................................................... xi Chapter 1. Introduction ................................................................................................... 1 1.1 Review of the fission products speciation and their chemical states in UO2 fuel. 6 1.2 Nuclear fission products speciation...................................................................... 7 1.2.1 Fission products speciation and chemical states in oxide fuels. ................... 8 1.2.2 Volatile fission products species ................................................................. 10 1.2.3 High volatile fission products ..................................................................... 11 1.2.4 Semi-volatile fission products species ........................................................ 15 1.2.5 Low volatile fission products including the lanthanides and the metallic precipitates: Y, La, Ce, Pr, Nd, Pm, Sm, Zr, Tc, Ru, Nb. ......................................... 18 1.3 Jacobian-free Newton-Krylov (JFNK) methods ................................................ 22 viii 1.4 Experimental of fission product in simulated LWR coolant chemistry ............. 26 Chapter 2. Fundamental data measurement of fission product .................................... 28 2.1 Solubility measurement of lanthanide oxide (La2O3, CeO2, Nd2O3) ................. 29 2.1.1 Experimental procedures for solubility measurement of lanthanide oxide (La2O3, CeO2, Nd2O3) ............................................................................................... 31 2.1.2 Result of solubility measurement................................................................ 35 2.2 Diffusion coefficient measurement of cesium iodide (CsI) in simulated LWR coolant chemistry using NMR technique. ..................................................................... 41 2.2.1 Experimental of diffusion coefficient measurement. .................................. 44 2.2.2 Diffusion coefficient data analysis.............................................................. 45 Chapter 3. Cesium release model development............................................................ 51 3.1 Model development-fuel oxidation .................................................................... 54 3.2 Hydrogen transport in fuel cracks ...................................................................... 57 3.3 Heat generation and conduction in the fuel and clad ......................................... 59 3.4 Cesium release from the defective fuel .............................................................. 64 3.5 BISON Kernel development. ............................................................................. 68 3.6 Model validation and cesium release result ....................................................... 71 Chapter 4. Summary ..................................................................................................... 83 References ......................................................................................................................... 87 ix List of Tables Table 1 Inventories of the main fission products and actinides in oxide fuel and their expected segregation tendencies [13] ................................................................................. 9 Table 2 Solubility of RE oxides in Boric acid water in different temperatures ................ 37 Table 3 Solubility measurement of RE oxides in Boric acid water in different temperatures (1000 ppm boric acid and 2 ppm lithium hydroxide) ....................................................... 40 Table 4 Concentration verification for La and Nd ...........................................................
Load more

Recommended publications
  • Re-Examining the Role of Nuclear Fusion in a Renewables-Based Energy Mix
    Re-examining the Role of Nuclear Fusion in a Renewables-Based Energy Mix T. E. G. Nicholasa,∗, T. P. Davisb, F. Federicia, J. E. Lelandc, B. S. Patela, C. Vincentd, S. H. Warda a York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD, UK b Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH c Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool, L69 3GJ, UK d Centre for Advanced Instrumentation, Department of Physics, Durham University, Durham DH1 3LS, UK Abstract Fusion energy is often regarded as a long-term solution to the world's energy needs. However, even after solving the critical research challenges, engineer- ing and materials science will still impose significant constraints on the char- acteristics of a fusion power plant. Meanwhile, the global energy grid must transition to low-carbon sources by 2050 to prevent the worst effects of climate change. We review three factors affecting fusion's future trajectory: (1) the sig- nificant drop in the price of renewable energy, (2) the intermittency of renewable sources and implications for future energy grids, and (3) the recent proposition of intermediate-level nuclear waste as a product of fusion. Within the scenario assumed by our premises, we find that while there remains a clear motivation to develop fusion power plants, this motivation is likely weakened by the time they become available. We also conclude that most current fusion reactor designs do not take these factors into account and, to increase market penetration, fu- sion research should consider relaxed nuclear waste design criteria, raw material availability constraints and load-following designs with pulsed operation.
    [Show full text]
  • Compilation and Evaluation of Fission Yield Nuclear Data Iaea, Vienna, 2000 Iaea-Tecdoc-1168 Issn 1011–4289
    IAEA-TECDOC-1168 Compilation and evaluation of fission yield nuclear data Final report of a co-ordinated research project 1991–1996 December 2000 The originating Section of this publication in the IAEA was: Nuclear Data Section International Atomic Energy Agency Wagramer Strasse 5 P.O. Box 100 A-1400 Vienna, Austria COMPILATION AND EVALUATION OF FISSION YIELD NUCLEAR DATA IAEA, VIENNA, 2000 IAEA-TECDOC-1168 ISSN 1011–4289 © IAEA, 2000 Printed by the IAEA in Austria December 2000 FOREWORD Fission product yields are required at several stages of the nuclear fuel cycle and are therefore included in all large international data files for reactor calculations and related applications. Such files are maintained and disseminated by the Nuclear Data Section of the IAEA as a member of an international data centres network. Users of these data are from the fields of reactor design and operation, waste management and nuclear materials safeguards, all of which are essential parts of the IAEA programme. In the 1980s, the number of measured fission yields increased so drastically that the manpower available for evaluating them to meet specific user needs was insufficient. To cope with this task, it was concluded in several meetings on fission product nuclear data, some of them convened by the IAEA, that international co-operation was required, and an IAEA co-ordinated research project (CRP) was recommended. This recommendation was endorsed by the International Nuclear Data Committee, an advisory body for the nuclear data programme of the IAEA. As a consequence, the CRP on the Compilation and Evaluation of Fission Yield Nuclear Data was initiated in 1991, after its scope, objectives and tasks had been defined by a preparatory meeting.
    [Show full text]
  • Uranium (Nuclear)
    Uranium (Nuclear) Uranium at a Glance, 2016 Classification: Major Uses: What Is Uranium? nonrenewable electricity Uranium is a naturally occurring radioactive element, that is very hard U.S. Energy Consumption: U.S. Energy Production: and heavy and is classified as a metal. It is also one of the few elements 8.427 Q 8.427 Q that is easily fissioned. It is the fuel used by nuclear power plants. 8.65% 10.01% Uranium was formed when the Earth was created and is found in rocks all over the world. Rocks that contain a lot of uranium are called uranium Lighter Atom Splits Element ore, or pitch-blende. Uranium, although abundant, is a nonrenewable energy source. Neutron Uranium Three isotopes of uranium are found in nature, uranium-234, 235 + Energy FISSION Neutron uranium-235, and uranium-238. These numbers refer to the number of Neutron neutrons and protons in each atom. Uranium-235 is the form commonly Lighter used for energy production because, unlike the other isotopes, the Element nucleus splits easily when bombarded by a neutron. During fission, the uranium-235 atom absorbs a bombarding neutron, causing its nucleus to split apart into two atoms of lighter mass. The first nuclear power plant came online in Shippingport, PA in 1957. At the same time, the fission reaction releases thermal and radiant Since then, the industry has experienced dramatic shifts in fortune. energy, as well as releasing more neutrons. The newly released neutrons Through the mid 1960s, government and industry experimented with go on to bombard other uranium atoms, and the process repeats itself demonstration and small commercial plants.
    [Show full text]
  • Radioactive Decay
    North Berwick High School Department of Physics Higher Physics Unit 2 Particles and Waves Section 3 Fission and Fusion Section 3 Fission and Fusion Note Making Make a dictionary with the meanings of any new words. Einstein and nuclear energy 1. Write down Einstein’s famous equation along with units. 2. Explain the importance of this equation and its relevance to nuclear power. A basic model of the atom 1. Copy the components of the atom diagram and state the meanings of A and Z. 2. Copy the table on page 5 and state the difference between elements and isotopes. Radioactive decay 1. Explain what is meant by radioactive decay and copy the summary table for the three types of nuclear radiation. 2. Describe an alpha particle, including the reason for its short range and copy the panel showing Plutonium decay. 3. Describe a beta particle, including its range and copy the panel showing Tritium decay. 4. Describe a gamma ray, including its range. Fission: spontaneous decay and nuclear bombardment 1. Describe the differences between the two methods of decay and copy the equation on page 10. Nuclear fission and E = mc2 1. Explain what is meant by the terms ‘mass difference’ and ‘chain reaction’. 2. Copy the example showing the energy released during a fission reaction. 3. Briefly describe controlled fission in a nuclear reactor. Nuclear fusion: energy of the future? 1. Explain why nuclear fusion might be a preferred source of energy in the future. 2. Describe some of the difficulties associated with maintaining a controlled fusion reaction.
    [Show full text]
  • Nuclear Reactors Fuelled with Uranium Inevitably Produce Plutonium As a By-Product
    The Secretary Joint Standing Committee on Treaties Inquiry into Nuclear Non-proliferation and Disarmament Dear Sir/Madam, I would like to submit the following submission to the Parliamentary Committee Inquiry into Nuclear Non- proliferation and Disarmament. Yours sincerely, Frank Barnaby. A submission to the Parliamentary Committee Inquiry into Nuclear Non- proliferation and Disarmament. Frank Barnaby Nuclear reactors fuelled with uranium inevitably produce plutonium as a by-product. This plutonium can be used by countries and by nuclear terrorists to fabricate nuclear weapons. The operation of nuclear-power reactors, therefore, has consequences for national, regional and global security. The more nuclear reactors there are the greater the security risks. Australia should recognise that these security risks outweigh the befits of producing electricity by nuclear power especially because the use of renewable sources of energy, combined with improvements in energy efficiency and the conservation of energy make the use of nuclear power unnecessary. As the world’s second largest exporter of uranium, Australia has a major responsibility to adopt policies to minimise the risks to security from nuclear proliferation and terrorism. To this end, Australia should use its influence to bring the Comprehensive Nuclear Test Ban Treaty (CTBT) into effect. It should not supply uranium to countries, like the USA and China, which have not yet ratified the CTBT. Moreover, Australia should promote the negotiation of a Comprehensive Fissile Material Cut-Off Treaty to prohibit the further production of fissile material usable for the production of nuclear weapons, prohibit the reprocessing of spent nuclear-power reactor fuel that has been produced by Australian uranium and should not support or encourage the use of Mixed Oxide (MOX) nuclear fuel or the use of Generation IV reactors, particularly fast breeder reactors.
    [Show full text]
  • Highly Enriched Uranium: Striking a Balance
    OFFICIAL USE ONLY - DRAFT GLOSSARY OF TERMS APPENDIX F GLOSSARY OF TERMS Accountability: That part of the safeguards and security program that encompasses the measurement and inventory verification systems, records, and reports to account for nuclear materials. Assay: Measurement that establishes the total quantity of the isotope of an element and the total quantity of that element. Atom: The basic component of all matter. Atoms are the smallest part of an element that have all of the chemical properties of that element. Atoms consist of a nucleus of protons and neutrons surrounded by electrons. Atomic energy: All forms of energy released in the course of nuclear fission or nuclear transformation. Atomic weapon: Any device utilizing atomic energy, exclusive of the means for transportation or propelling the device (where such means is a separable and divisible part of the device), the principal purpose of which is for use as, or for development of, a weapon, a weapon prototype, or a weapon test device. Blending: The intentional mixing of two different assays of the same material in order to achieve a desired third assay. Book inventory: The quantity of nuclear material present at a given time as reflected by accounting records. Burnup: A measure of consumption of fissionable material in reactor fuel. Burnup can be expressed as (a) the percentage of fissionable atoms that have undergone fission or capture, or (b) the amount of energy produced per unit weight of fuel in the reactor. Chain reaction: A self-sustaining series of nuclear fission reactions. Neutrons produced by fission cause more fission. Chain reactions are essential to the functioning of nuclear reactors and weapons.
    [Show full text]
  • X-Ray and Neutron Sources
    Chapter 1: Radioactivity Radioactivity from Direct Excitation X‐ray Emission 147 NPRE 441, Principles of Radiation Protection An Overview of Radiation Exposure to US Population 148 NPRE 441, Principles of Radiation Protection Chapter 1: Radioactivity Clinical X‐ray CT System The Siemens SOMATOM X clinical CT system 149 Chapter 1: Radioactivity X‐ray Imaging Examples 150 NPRE 441, Principles of Radiation Protection Chapter 1: Radioactivity X‐ray Generation –X‐ray Tube Andrew Webb, Introduction to Biomedical Imaging, 2003, Wiley‐ Interscience. Motor, Why? Filament Rotating target Electron beam? How are electrons generated? 151 NPRE 441, Principles of Radiation Protection Chapter 1: Radioactivity X‐ray Generation – Bremsstrahlung • Target nucleus positive charge (Z∙p+) attracts incident e‐ • Deceleration of an incident e‐ occurs in the proximity of the target atom nucleus • Energylostbye‐ is gained by the EM photon (x‐ray) generated • The impact parameter distance, the closest approach to the nucleus by the e‐ determines the amount of E loss • The Coulomb force of attraction varies strongly with distance ( 1/r2); ↓ distance →↑deceleration and E loss →↑photon E • Direct impact on the nucleus determines the maximum x‐ray E (Emax) 152 NPRE 441, Principles of Radiation Protection Chapter 1: Radioactivity X‐ray Generation – Bremsstrahlung Interestingly, this process creates a relatively uniform spectrum. Intensity = nh 0 Photon energy spectrum 153 NPRE 441, Principles of Radiation Protection Chapter 1: Radioactivity The Unfiltered Bremsstrahlung Spectrum Thick Target X‐ray Formation We can model target as a series of thin targets. Electrons successively loses energy as they moves deeper into the target. Electrons X‐rays Relative Intensity 0 Each layer produces a flat energy spectrum with decreasing peak energy level.
    [Show full text]
  • Nuclear Reactions Fission Fusion
    Nuclear Reactions Fission Fusion Nuclear Reactions and the Transmutation of Elements A nuclear reaction takes place when a nucleus is struck by another nucleus or particle. Compare with chemical reactions ! If the original nucleus is transformed into another, this is called transmutation. a-induced Atmospheric reaction. 14 14 n-induced n 7N 6C p Deuterium production reaction. 16 15 2 n 8O 7 N 1H Note: natural “artificial” radioactivity Nuclear Reactions and the Transmutation of Elements Energy and momentum must be conserved in nuclear reactions. Generic reaction: The reaction energy, or Q-value, is the sum of the initial masses less the sum of the final masses, multiplied by c2: If Q is positive, the reaction is exothermic, and will occur no matter how small the initial kinetic energy is. If Q is negative, there is a minimum initial kinetic energy that must be available before the reaction can take place (endothermic). Chemistry: Arrhenius behaviour (barriers to reaction) Nuclear Reactions and the Transmutation of Elements A slow neutron reaction: is observed to occur even when very slow-moving neutrons (mass Mn = 1.0087 u) strike a boron atom at rest. 6 Analyze this problem for: vHe=9.30 x 10 m/s; Calculate the energy release Q-factor This energy must be liberated from the reactants. (verify that this is possible from the mass equations) Nuclear Reactions and the Transmutation of Elements Will the reaction “go”? Left: M(13-C) = 13.003355 Right: M(13-N) = 13.005739 M(1-H) = 1.007825 + M(n) = 14.014404 D(R-L)= 0.003224 u (931.5 MeV/u) = +3.00 MeV (endothermic) Hence bombarding by 2.0-MeV protons is insufficient 3.0 MeV is required since Q=-3.0 MeV (actually a bit more; for momentum conservation) Nuclear Reactions and the Transmutation of Elements Neutrons are very effective in nuclear reactions, as they have no charge and therefore are not repelled by the nucleus.
    [Show full text]
  • Chapter 4 Radioactivity and Medicine a CT Scan (Computed Tomography)
    Chapter 4 Radioactivity and Medicine A CT scan (computed tomography) of the brain using X-ray beams A radioactive isotope has an unstable nucleus; it emits radiation to become more stable and can be one or more of the isotopes of an element Alpha (α) particle +2 is two protons and two neutrons, a helium nucleus Beta (β) particle is a high-energy electron Positron (β+) is a positive electron (an extract from a proton) Gamma (γ ) ray is high-energy released from a nucleus in the form of electromagnetic radiation Radiation protection requires paper and clothing for alpha particles a lab coat or gloves for beta particles a lead shield or a thick concrete wall for gamma rays limiting the amount of time spent near a radioactive source increasing your distance from the source Note that the atomic mass and atomic number are reversed in the equation but that the sum of the atomic masses and numbers in the reactant (U) equals the sum in the products (Th and He) Remember that the mass of an electron is very small compared to neutrons and protons and that a neutron can be thought of as a proton and electron combined 19 Write an equation for the decay of K42 (potassium-42), a beta (electron) emitter. 19 -1 K42 eo + ? Mass number of ? same (42) Atomic number of ? This electron is emitted from the nucleus, not from one of the outer electrons A neutron must have been split to give an electron and a proton 0 + -1 n1 = p1 + e0 20 ?42 20 Ca42 +1 In positron emission, a proton is converted to a neutron and positron, e0 49 +1 Mn25 e0 + ? In this case the nucleus
    [Show full text]
  • Ternary and Quaternary Fission
    FEATURES Ternary and quaternary fission Friedrich Gönnenwein 1, Manfred Mutterer2 and Yuri Kopatch 3 1 Physikalisches Institut, Universität Tübingen, Germany 2 Institut für Kernphysik, Technische Universität Darmstadt, Germany 3 Frank Laboratory of Neutron Physics, JINR, Dubna, Russia N uclear fission has become known in the late thirties of the last century as a process where a heavy nucleus such as Ura­ nium or Thorium decays into two fragments of about the same Fig. 5: Time variations of the apex height in dimensionless mass. The process was discovered while irradiating natural Urani­ coordinates for a sessile drop measured during solvent loss um with thermal neutrons [1] and it soon became evident that at low humidity rate (RH=30%; 6o=40°;R0=3.1 mm). After the among the U-isotopes it was 235U to be held responsible for the primary buckling instability leading to an axisymmetric reaction 235U(nth,f ) observed. Shortly afterwards it was found that "peak) a secondary instability takes place and breaks the heavy nuclei such as 238U may also undergo fission spontaneously axisymmetry of the drop. Inset: image taken at 45° of such drop at the final stage of the drying process: radial wrinkles Whether by spontaneous or induced fission, the mother are clearly observable all around the peak formed by the first nucleus disintegrates in the overwhelming fraction of cases just buckling instability (also in Figure 4b). into two fragments. Fragmentation into three or more daughter nuclei of about equal mass has up to the present not been detect­ cascade of buckling events takes place, resulting in a complex ed unambiguously.
    [Show full text]
  • RCC-Mrx Chairwoman CEA - Senior Expert in Design Codes and Standards for Mechanical Components
    Shaping the rules for a sustainable nuclear technology How to introduce new materials in design codes Cécile PÉTESCH RCC-MRx chairwoman CEA - Senior Expert in design codes and standards for mechanical components SNETP FORUM 2021 Towards innovative R&D in civil nuclear fission AFCEN is ISO 9001:2015 certified © 2021 www.afcen.com | 1 Shaping the rules for a sustainable nuclear technology Design codes vs new material Why? Interest to connect R&D to standardisation What? Example of RCC-MRx code How? Difficulties to introduce a new material Conclusion SNETP FORUM 2021 Towards innovative R&D in civil nuclear fission AFCEN is ISO 9001:2015 certified © 2021 www.afcen.com | 2 Shaping the rules for a sustainable nuclear technology Design codes vs new material Why? Interest to connect R&D to standardisation What? Example of RCC-MRx code How? Difficulties to introduce a new material Conclusion SNETP FORUM 2021 Towards innovative R&D in civil nuclear fission AFCEN is ISO 9001:2015 certified © 2021 www.afcen.com | 3 Why? Codes and standards Modification request Material file Nuclear Industry New Material SNETP FORUM 2021 Towards innovative R&D in civil nuclear fission AFCEN is ISO 9001:2015 certified © 2021 www.afcen.com | 4 Why? Codes and standards DMRx Material file REGULATOR New Material SNETP FORUM 2021 Towards innovative R&D in civil nuclear fission AFCEN is ISO 9001:2015 certified © 2021 www.afcen.com | 5 Why? For innovative reactors, standardization is one way to reach a highest technology readiness level, giving a frame and a direction
    [Show full text]
  • EIA Energy Kids Page- Nuclear Energy (Fusion and Fission), Uranium, Atomic Energy
    NUCLEAR ENERGY (URANIUM) ENERGY FROM ATOMS Nuclear Energy is Energy from Atoms Nuclear Fuel- Uranium Nuclear Power Plants Generate Electricity Types of Reactors Nuclear Power and the Environment links page recent statistics NUCLEAR ENERGY IS ENERGY FROM ATOMS Nuclear energy is energy in the nucleus (core) of an atom. Atoms are tiny particles that make up every object in the universe. There is enormous energy in the bonds that hold atoms together. Nuclear energy can be used to make electricity. But first the energy must be released. It can be released from atoms in two ways: nuclear fusion and nuclear fission. In nuclear fusion, energy is released when atoms are combined or fused together to form a larger atom. This is how the sun produces energy. In nuclear fission, atoms are split apart to form smaller atoms, releasing energy. Nuclear power plants use nuclear fission to produce electricity. NUCLEAR FUEL - URANIUM The fuel most widely used by nuclear plants for nuclear fission is uranium. Uranium is nonrenewable, though it is a common metal found in rocks all over the world. Nuclear plants use a certain kind of uranium, U-235, as fuel because its atoms are easily split apart. Though uranium is quite common, about 100 times more common than silver, U-235 is relatively rare. Most U.S. uranium is mined, in the Western United States. Once uranium is mined the U-235 must be extracted and processed before it can be used as a fuel. During nuclear fission, a small particle called a neutron hits the uranium atom and splits it, releasing a great amount of energy as heat and radiation.
    [Show full text]