One of the greatest challenges for nuclear energy is how to properly manage the highly radioactive waste generated during irradiation in nuclear reactors. Accelerator Driven Systems (ADSs) may offer new prospects and advantages for the transmutation of such high level nuclear waste. ADS or accelerator driven transmutation of waste (ATW) consists of a high power proton accelerator, a heavy metal spallation target that produces neutrons when bombarded by the high power beam, and a sub-critical core that is neutronically coupled to the spallation target. This publication provides a comprehensive state of the art of the ADS technology by representing the different ADS concepts proposed worldwide in the last 15 years, as well as the related R&D activities and demonstration initiatives carried out at national international level.

This publication presents the results and conclusions of an international research collaboration devoted to gaining a better understanding of the physics of Accelerator Driven Subcritical Systems (ADS), with particular emphasis on using low enriched uranium (LEU) fuel. The publication contains information on nine ADS facilities, including descriptions of the hardware deployed, experiments conducted, computational resources and procedures used in the analyses, principal results obtained, and conclusions drawn from the knowledge gained as a consequence of this work. It is intended to provide information for users of ADS systems and those involved in the design of new ADS facilities to use LEU fuel and in the conversion of some existing facilities from using highly enriched Uranium (HEU) to LEU.

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.

This book covers essential aspects of transmutation technologies, highlighting especially the advances in Japan. The accident at the Fukushima Daiichi Nuclear Power Plant (NPP) has caused us to focus attention on a large amount of spent nuclear fuels stored in NPPs. In addition, public anxiety regarding the treatment and disposal of high-level radioactive wastes that require long-term control is growing. The Japanese policy on the back-end of the nuclear fuel cycle is still unpredictable in the aftermath of the accident. Therefore, research and development for enhancing the safety of various processes involved in nuclear energy production are being actively pursued worldwide. In particular, nuclear transmutation technology has been drawing significant attention after the accident. This publication is timely with the following highlights: 1) Development of accelerator-driven systems (ADSs), which is a brand-new reactor concept for transmutation of highly radioactive wastes; 2) Nuclear reactor systems from the point of view of the nuclear fuel cycle. How to reduce nuclear wastes or how to treat them including the debris from TEPCO’s Fukushima nuclear power stations is discussed; and 3) Environmental radioactivity, radioactive waste treatment and geological disposal policy. State-of-the-art technologies for overall back-end issues of the nuclear fuel cycle as well as the technologies of transmutation are presented here. The chapter authors are actively involved in the development of ADSs and transmutation-related technologies. The future of the back-end issues in Japan is very uncertain after the accident at the Fukushima Daiichi NPP and this book provides an opportunity for readers to consider the future direction of those issues.

This book offers a comprehensive overview of the reprocessing of spent nuclear fuels, and discusses the applications of radiation, particularly spallation neutrons and gamma rays. The unspent nuclear fuel of a reactor amounts to roughly 95 per cent of the loaded fuel. It contains both fertile and fissile fuels, minor and higher actinides and radioactive fission products. In 2015, out of approximately 4 million metric tons of spent fuel, only 90,000 metric tons was reprocessed worldwide; the rest was either sent to repositories, kept for cooling down, or put on a waiting list for future reprocessing. With regard to the direct reutilization of spent nuclear fuel, the new technique of ‘Energy Amplifiers’ has attracted considerable attention among the nuclear energy community. Presenting extensive information on this technique, the book is divided into eight major sections: (i) spent nuclear fuel and alternative transmutation methods, (ii) general concept of accelerator-driven subcritical systems (ADSS), (iii) spallation neutron sources and the possibility of incineration, (iv) requirements for nuclear data, (v) transmutation of spent nuclear fuel and extension of the fuel cycle, (vi) spallation neutron production facilities, (vii) major experimental facilities for ADSS, and (viii) software tools for the design and modelling of ADSS. The book is ideally suited as a textbook for graduate students as well as a reference guide for researchers and practitioners.

"In this analysis we have presented a method that provides insight into future fuel cycle alternatives by clarifying the complexity of choosing an appropriate fuel cycle in the context of the distribution of burdens and benefits between generations. The current nuclear power deployment practices, together with three future fuel cycles were assessed."--Page 227.

Research reactor fuel technology continues to evolve, driven in part by international efforts to develop high density fuels to enable the conversion of more reactors from highly enriched uranium (HEU) to low enriched uranium (LEU) fuels. These high density fuels may offer economic benefits for research reactors, despite being more expensive initially, because they offer the prospect of higher per-assembly burnup, thus reducing the number of assemblies that must be procured, and more flexibility in terms of spent fuel management compared to the currently qualified and commercially available LEU silicide fuels. Additionally, these new fuels may offer better performance characteristics. This publication provides a preliminary evaluation of the impacts on research reactor performance and fuel costs from using high density fuel. Several case studies are presented and compared to illustrate these impacts.