Download or read book Non Proliferative Thorium Based Core and Fuel Cycle for Pressurized Water Reactors written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Two of the major barriers to the expansion of worldwide adoption of nuclear power are related to proliferation potential of the nuclear fuel cycle and issues associated with the final disposal of spent fuel. The Radkowsky Thorium Fuel (RTF) concept proposed by Professor A. Radkowsky offers a partial solution to these problems. The main idea of the concept is the utilization of the seed-blanket unit (SBU) fuel assembly geometry which is a direct replacement for a 'conventional' assembly in either a Russian pressurized water reactor (VVER-1000) or a Western pressurized water reactor (PWR). The seed-blanket fuel assembly consists of a fissile (U) zone, known as seed, and a fertile (Th) zone known as blanket. The separation of fissile and fertile allows separate fuel management schemes for the thorium part of the fuel (a subcritical 'blanket') and the 'driving' part of the core (a supercritical 'seed'). The design objective for the blanket is an efficient generation and in-situ fissioning of the U233 isotope, while the design objective for the seed is to supply neutrons to the blanket in a most economic way, i.e. with minimal investment of natural uranium. The introduction of thorium as a fertile component in the nuclear fuel cycle significantly reduces the quantity of plutonium production and modifies its isotopic composition, reducing the overall proliferation potential of the fuel cycle. Thorium based spent fuel also contains fewer higher actinides, hence reducing the long-term radioactivity of the spent fuel. The analyses show that the RTF core can satisfy the requirements of fuel cycle length, and the safety margins of conventional pressurized water reactors. The coefficients of reactivity are comparable to currently operating VVER's/PWR's. The major feature of the RTF cycle is related to the total amount of spent fuel discharged for each cycle from the reactor core. The fuel management scheme adopted for RTF core designs allows a significant decrease in the amount of discharged spent fuel, for a given energy production, compared with standard VVER/PWR. The total Pu production rate of RTF cycles is only 30 % of standard reactor. In addition, the isotopic compositions of the RTF's and standard reactor grade Pu are markedly different due to the very high burnup accumulated by the RTF spent fuel.

Download or read book Proliferation proof Uranium Plutonium and Thorium Uranium Fuel Cycles Safeguards and Non Proliferation written by Kessler, Guenter and published by KIT Scientific Publishing. This book was released on 2017-02-20 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermal and neutron physics analysis show that above certain concentrations of the isotope Pu-238 hypothetical nuclear explosive devices, made of reactor-grade plutonium, are technically not feasible. Future proliferation-proof fuel cycles are proposed which make use of methods of actinide tansmutation.Reactors operating in the thorium/uranium fuel cyce are loaded with

Download or read book Thorium Fuel Cycle written by Fouad Sabry and published by One Billion Knowledgeable. This book was released on 2022-10-15 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: What Is Thorium Fuel Cycle The fertile material in the thorium fuel cycle is an isotope of thorium called 232Th, and the thorium fuel cycle itself is a kind of nuclear fuel cycle. Within the reactor, 232Th is converted into the fissile artificial uranium isotope 233U, which is then used as the fuel for the nuclear reactor. Natural thorium, in contrast to natural uranium, only contains minute quantities of fissile material, which is insufficient to kick off a nuclear chain reaction. In order to kickstart the fuel cycle, either more fissile material or an other neutron source is required. 233U is created when 232Th, which is powered by thorium, absorbs neutrons in a reactor. This is analogous to the process that occurs in uranium breeder reactors, in which fertile 238U is subjected to neutron absorption in order to produce fissile 239Pu. The produced 233U either fissions in situ or is chemically removed from the old nuclear fuel and converted into new nuclear fuel, depending on the architecture of the reactor and the fuel cycle. Fissioning in situ is the more efficient method. How You Will Benefit (I) Insights, and validations about the following topics: Chapter 1: Thorium fuel cycle Chapter 2: Nuclear reactor Chapter 3: Radioactive waste Chapter 4: Fissile material Chapter 5: Nuclear fuel cycle Chapter 6: MOX fuel Chapter 7: Breeder reactor Chapter 8: Uranium-238 Chapter 9: Energy amplifier Chapter 10: Subcritical reactor Chapter 11: Integral fast reactor Chapter 12: Fertile material Chapter 13: Uranium-233 Chapter 14: Plutonium-239 Chapter 15: Isotopes of uranium Chapter 16: Isotopes of plutonium Chapter 17: Weapons-grade nuclear material Chapter 18: Uranium-236 Chapter 19: Burnup Chapter 20: Liquid fluoride thorium reactor Chapter 21: Nuclear transmutation (II) Answering the public top questions about thorium fuel cycle. (III) Real world examples for the usage of thorium fuel cycle in many fields. (IV) 17 appendices to explain, briefly, 266 emerging technologies in each industry to have 360-degree full understanding of thorium fuel cycle' technologies. Who This Book Is For Professionals, undergraduate and graduate students, enthusiasts, hobbyists, and those who want to go beyond basic knowledge or information for any kind of thorium fuel cycle.

Download or read book Thorium Fuel Cycle written by International Atomic Energy Agency and published by . This book was released on 2005 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides a critical review of the thorium fuel cycle: potential benefits and challenges in the thorium fuel cycle, mainly based on the latest developments at the front end of the fuel cycle, applying thorium fuel cycle options, and at the back end of the thorium fuel cycle.

Download or read book Molten Salt Reactors and Thorium Energy written by Thomas James Dolan and published by Elsevier. This book was released on 2024-01-25 with total page 1068 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molten Salt Reactors and Thorium Energy, Second Edition is a fully updated comprehensive reference on the latest advances in MSR research and technology. Building on the successful first edition, Tom Dolan and the team of experts have fully updated the content to reflect the impressive advances from the last 5 years, ensuring this book continues to be the go-to reference on the topic. This new edition covers progress made in MSR design, details innovative experiments, and includes molten salt data, corrosion studies and deployment plans. The successful case studies section of the first edition have been removed, expanded, and fully updated, and are now published in a companion title called Global Case Studies on Molten Salt Reactors. Readers will gain a deep understanding of the advantages and challenges of MSR development and thorium fuel use, as well as step-by-step guidance on the latest in MSR reactor design. Each chapter provides a clear introduction, covers technical issues and includes examples and conclusions, while promoting the sustainability benefits throughout. A fully updated comprehensive handbook on Molten Salt Reactors and Thorium Energy, written by a team of global experts Covers MSR applications, technical issues, reactor types and reactor designs Includes 3 brand new chapters which reflect the latest advances in research and technology since the first edition published Presents case studies on molten salt reactors which aid in the transition to net zero by providing abundant clean, safe energy to complement wind and solar powe

Download or read book Nuclear Reactor Core Fuel Cycle Analysis and Computation for Pressurized Water Reactors written by Mohamed A. Elmaghrabi and published by . This book was released on 1979 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Evaluation of the Net Breeding Capability of Heterogeneously fuelled Pressure tube Heavy Water Reactors with the Thorium Fuel Cycle written by Sourena Golesorkhi and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Fuel Cycle and Reactor Concepts written by International Nuclear Fuel Cycle Evaluation and published by . This book was released on 1980 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thorium Fuel cycle Alternatives written by Thomas H. Pigford and published by . This book was released on 1978 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optimization of a Seed and Blanket Thorium uranium Fuel Cycle for Pressurized Water Reactors written by Dean Wang and published by . This book was released on 2003 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) Fuel performance was analyzed using FRAPCON. The radioactivity and decay heat from the spent seed and blanket fuel were studied using MIT's MCODE (which couples MCNP and ORIGEN) to do depletion calculations, and ORIGEN to analyze the spent fuel characteristics after discharge. The analyses show that the WASB core can satisfy the requirements of fuel cycle length and safety margins of conventional PWRs. The coefficients of reactivity are comparable to currently operating PWRs. However, the reduction in effective delayed neutron fraction (eff) requires careful review of the control systems because of its importance to short term power transients. Whole core analyses show that the total control rod worth of the WASB core is about 1/3 less than those of a typical PWR for a standard arrangement of Ag-In-Cd control rods in the core. The use of enriched boron in the control rods can effectively improve the control rod worth. The control rods have higher worth in the seed than in the blanket. Therefore, a new loading pattern has been designed so that almost all the control rods will be located in seed assemblies. However, the new pattern requires a redesign of the vessel head of the reactor, which is an added cost in case of retrofitting in existing PWRs. Though the WASB core has high power peaking factors, acceptable MDNBR in the core can be achieved under conservative assumptions by using grids with large local pressure loss coefficient in the blanket. However, the core pressure drop will increase by 70% ...

Download or read book Evaluation of Denatured Thorium Fuel Cycles in Pressurized Water Reactors written by and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A developing national energy policy that is based in part on a substantial expansion of the LWR-based electrical generating capacity with deferment of the LMFBR has prompted a re-evaluation of our nuclear fuel resources and their utilization. The ancillary policy of minimizing nuclear weapons proliferation through diversion of bred fissile material has left in doubt the viability of fuel recycling as a means of extending these fuel resources. A substantial, government-sponsored effort is in progress to examine alternate fuel cycles and advanced reactor concepts which can lead to improved resource utilization while minimizing proliferation potential. This paper evaluates several improved fuel cycles for use in current design PWRs and develops selected scenarios for their use within the framework of the safeguarded Nuclear Energy Center (NEC) concept.

Download or read book Thorium Fuel Cycle written by Raymond G. Wymer and published by . This book was released on 1968 with total page 870 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Assessment of Thorium Fuel Cycles in Pressurized Water Reactors written by and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of a Design for a Retrofit Seed blanket Core for a Pressurized Water Reactor Using a Uranium thorium Fuel Cycle written by and published by . This book was released on 1984 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Th written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of thorium in current or advanced light water reactors (LWRs) has been of interest in recent years. These interests have been associated with the need to increase nuclear fuel resources and the perceived non-proliferation advantages of the utilization of thorium in the fuel cycle. Various options have been considered for the use of thorium in the LWR fuel cycle including: (1) its use in a once-through fuel cycle to replace non-fissile uranium or to extend fuel burnup due to its attractive fertile material conversion, (2) its use for fissile plutonium burning in limited recycle cores, and (3) its advantage in limiting the transuranic elements to be disposed off in a repository (if only Th/U-233 fuel is used). The possibility for thorium utilization in multirecycle system has also been considered by various researchers, primarily because of the potential for near breeders with Th/U-233 in the thermal energy range. The objective of this project is to evaluate the potential of the Th/U-233 fuel multirecycle in current LWRs, with focus this year on pressurized water reactors (PWRs). In this work, approaches for ensuring a sustainable multirecycle without the need for external source of makeup fissile material have been investigated. The intent is to achieve a design that allows existing PWRs to be used with minimal modifications. In all cases including homogeneous and heterogeneous assembly designs, the assembly pitch is kept consistent with that of the current PWRs (21.5 cm used). Because of design difficulties associated with using the same geometry and dimensions as a PWR core, the potential modifications (other than assembly pitch) that would be needed for PWRs to ensure a sustainable multirecycle system have been investigated and characterized. Additionally, the implications of the use of thorium on the LWR fuel cycle are discussed. In Section 2, background information on studies evaluating the use of thorium in the fuel cycle is provided, but focusing on Th/U-233 multirecycle. Recent studies done internationally and in the U.S. are briefly summarized. Additionally, the previous U.S. thorium breeder experiment in the Shippingport reactor is briefly discussed. The objective of this work and the reactor design issues associated with multirecycle of Th/U-233 are discussed in Section 3. The approaches required to achieve a sustainable system are discussed and evaluated. Homogeneous assembly modeling results are presented in this section. In Section 4, a 17-by-17 heterogeneous assembly design has been selected and evaluated, based on its positive attributes for sustainable Th/U-233 multirecycle. A feasibility study is briefly discussed at the end of this section followed by recommendations for future activities. Section 5 discusses the attributes of the 17-by-17 heterogeneous assembly design. The material mass flow data and fuel cycle impact data are reported in this section. Discussions on the fuel cycle implications of thorium fuel utilization are provided in Section 6. This includes information on fuel sources, fuel manufacturing, fuel reprocessing, and re-fabrication. The conclusions of the study are provided in Section 7.

Download or read book OPTIMIZATION OF HETEROGENEOUS UTILIZATION OF THORIUM IN PWRS TO ENHANCE PROLIFERATION RESISTANCE AND REDUCE WASTE written by and published by . This book was released on 2004 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues affecting the implementation, public perception and acceptance of nuclear power include: proliferation, radioactive waste, safety, and economics. The thorium cycle directly addresses the proliferation and waste issues, but optimization studies of core design and fuel management are needed to ensure that it fits within acceptable safety and economic margins. Typical pressurized water reactors, although loaded with uranium fuel, produce 225 to 275 kg of plutonium per gigawatt-year of operation. Although the spent fuel is highly radioactive, it nevertheless offers a potential proliferation pathway because the plutonium is relatively easy to separate, amounts to many critical masses, and does not present any significant intrinsic barrier to weapon assembly. Uranium 233, on the other hand, produced by the irradiation of thorium, although it too can be used in weapons, may be ''denatured'' by the addition of natural, depleted or low enriched uranium. Furthermore, it appears that the chemical behavior of thoria or thoria-urania fuel makes it a more stable medium for the geological disposal of the spent fuel. It is therefore particularly well suited for a once-through fuel cycle. The use of thorium as a fertile material in nuclear fuel has been of interest since the dawn of nuclear power technology due to its abundance and to potential neutronic advantages. Early projects include homogeneous mixtures of thorium and uranium oxides in the BORAX-IV, Indian Point I, and Elk River reactors, as well as heterogeneous mixtures in the Shippingport seed-blanket reactor. However these projects were developed under considerably different circumstances than those which prevail at present. The earlier applications preceded the current proscription, for non-proliferation purposes, of the use of uranium enriched to more than 20 w/o in 235U, and has in practice generally prohibited the use of uranium highly enriched in 235U. They were designed when the expected burnup of light water fuel was on the order of 25 MWD/kgU--about half the present day value--and when it was expected that the spent fuel would be recycled to recover its fissile content.

Download or read book Application of Advanced Fuel Concepts for Use in Innovative Pressurized Water Reactors written by Nathan Christopher Andrews and published by . This book was released on 2015 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work addresses several specific knowledge gaps that exist in the use of alternative fuel and cladding combinations in a pressurized water reactor (PWR) environment. In the switch from a UO2 with zirconium-based cladding to any other combination, there is a multitude of questions that need to be answered. This work examines three of these knowledge gaps: (1) the disposition of weapons-grade plutonium in thorium and silicon carbide cladding, (2) economics of accident tolerant fuel (ATF) claddings and (3) breeding of plutonium in uranium nitride fuel. Burning weapons-grade plutonium in a standard pressurized water reactor (PWR) using thoria as a fuel matrix has been compared to using urania. Two cladding options were considered: a 0.76 mm thick silicon carbide ceramic matrix composite (SiC CMC) and 0.57 mm thick standard Zircaloy cladding. A large benefit was found in using thoria compared to urania in terms of plutonium percentage and mass burned. A slightly smaller mass of plutonium is required in a core with SiC CMC cladding, due to its lower neutron absorption compared to Zircaloy. The thorium system was also better from a non-proliferation viewpoint, resulting in less fissile mass at discharge and more fissile mass burned over an assembly's lifetime. A limited safety comparison was made for two reactivity insertion accidents: (1) highest worth rod ejection accident (REA) and (2) main steam line break (MSLB). The MSLB accident demonstrated a safe value for the minimum departure from nucleate boiling ratio. The maximum enthalpy added to the fuel during the REA was also below current regulatory limits for PWRs. This indicates that the more negative moderator temperature coefficients of thoria-plutonia and urania-plutonia fuel, compared to a typical PWR design, were not limiting. For an ATF cladding to replace zirconium alloys, it must be economically viable by having similar fuel cycle costs to today's materials. Four proposed materials are examined: stainless steel (SS), FeCrAl alloy, molybdenum (Mo) and SiC CMC, each having its own development time and costs. The chosen cladding thicknesses were dependent on strength and manufacturing constraints. It was found that all options may end up requiring higher enrichment than zirconium-based claddings for the same fuel cycle length. If the present value of avoiding a reactor accident with a large radioactivity release is estimated using past experience for LWR large accidents and if it is assumed that ATF cladding is able to prevent such release, there is a definite net economic benefit relative to typical Zircaloy cladding only in using SiC, since it only results in a small fuel cycle cost increase. There is only a marginal benefit in using SiC to prevent a core-only loss without radioactivity release (TMI-type) accident and a large loss using metallic ATF concepts. The thermal hydraulic and neutronic feasibility of a nitride fueled pressurized water reactor (PWR) breeder design were examined. Because of its higher fuel density, nitride fuel would be preferable to traditional oxide fuel in attempting to achieve breeding in a PWR. The design chosen uses large hexagonal assemblies with 14 inner seed pin rows and 4 outer blanket pin rows. In this design, reactor grade plutonium of 12.75 wtHM was used as fuel. Nitride was also simulated as being 100% N-15, to limit neutronic penalties and C-14 production. The as specified assembly model only achieved a fissile inventory ratio (FIR) value above 1.0 when the thimble regions were assumed to be voided, which lowers the H/HM ratio in the assembly. This led to FIR values above 1.0 for the oxide, 85% theoretical density nitride (N85) and 95% theoretical density nitride (N95). All were at an FIR of 1.03 at 35 MWd/kgHM. However, the single batch discharge burnup of the voided assembly in MWd/kgHM was 32.2 for N95, 24.5 for N85, while only 15.6 for the oxide.