Technical Meeting on Passive Shutdown Systems for LMFR Vienna, 20-22 October 2015 Overview of Activities in the Field of Safety of FR Outline of the Technical Meeting Stefano Monti Nuclear Power Technology Development Section Department of Nuclear Energy International Atomic Energy Agency
Department of Nuclear Energy The mission of the Department of Nuclear Energy is characterized by three keywords: support, catalyse and build The Department fosters the efficient and safe use of nuclear power by supporting existing and new nuclear programmes around the world, catalysing innovation and building indigenous capability in energy planning, analysis, and nuclear information and knowledge. 2
Department of Nuclear Energy & NPTDS & FR 3
Nuclear Power Technology Development https://www.iaea.org/nuclearpower/technology/home.html Programme Areas & Contacts Stefano Monti S.Monti@iaea.org Ibrahim Khamis I.Khamis@iaea.org NPTDS and Fast Reactors http://www.iaea.org/nuclearpower/technology/home.html http://www.iaea.org/nuclearpower/fr/ Non-Electrical Applications (Desalination, Cogeneration Hydrogen production) http://www.iaea.org/nuclearpower/nea/ Mark Harper M.J.Harper@iaea.org Water-cooled Reactors (PWR, BWRs..) http://www.iaea.org/nuclearpower/wcr/ Matthias Krause M.Krause@iaea.org Katsumi Yamada K.Yamada@iaea.org Chad Painter C.Painter@iaea.org Frederik Reitsma F.Reitsma@iaea.org Hadid Subki M.Subki@iaea.org Heavy Water Reactors http://www.iaea.org/nuclearpower/wcr/ Super Critical Water Reactors Plant Simulators, training http://www.iaea.org/nuclearpower/simulators/index.html High Temperature Gas Cooled Reactors http://www.iaea.org/nuclearpower/gcr/ Small Modular and Medium-sized Reactors http://www.iaea.org/nuclearpower/smr/
NPTDS Support to Member States Exchange of information on all reactor technologies (LWR, HWR, FR, ADS, GCR, SMR, Non-electric applications) TWGs Objective information to all Member States on reactor technology status and development trends: Advanced Reactor Information System (ARIS) Reactor technology assessment and selection approaches for near-term deployment embarking countries Implementation of post-fukushima R&D and Innovation in reactor technology Technology Roadmap for SMRs and Advanced Reactor Deployments Collaborative researches (CRP, ICSP) for improving safety, reliability, availability and economy of advanced reactors Support to NS for development of safety standards for advanced reactors Education & Training: Workshops, Training Courses, Schools, IT tools Knowledge preservation (e.g. FRKP Portal) PC-based simulators development, maintenance and distribution Toolkits for non-electrical applications and Sever Accident Management Cooperate with GIF, OECD/NEA and EC in the area of advanced reactors 5
Nuclear Power Technology Development https://www.iaea.org/nuclearpower/technology/home.html
Rationale and Programmatic Approach for Fast Reactor Activities 7
Challenges and Opportunities for FR At present, there is a wide convergence on the choice of sodium as coolant, with oxide, metal (e.g. for high conversion ratio) or nitride fuel. However, it seems important to explore/develop a viable backup option, such as lead (or lead-bismuth) coolant with oxide or nitride fuel, or gas coolant with carbide fuel. In this context, an innovative sodium-cooled prototype and a demo/experimental plant for exploring a backup option should/could be the focus of international initiatives. Other internationally recognized major challenges are: The very limited availability of fast spectrum irradiation facilities, in particular to test and qualify advanced materials, fuels and targets (currently only BOR-60 in Russian Federation and FBTR in India); The industrial demonstration of a fully closed fuel cycle with fast reactors, including the multi-recycling of the fuel as well as the (homogenous or heterogeneous) partitioning and transmutation of minor actinides (Am, Cm and Np). 8
Other Important Medium-term Challenges High availability and reliability (a major utility requirement); Plant simplification and cost reduction; Integration of Fukushima accident feedbacks; Internationally agreed safety approaches, design criteria and guidelines; Feasibility of cores with low or even negative void worth; Specific tools for ISI&R and core monitoring; Enhanced fuel and cladding performances in order to achieve core performances beyond 20-30 at.% burnup and beyond 200 dpa; Innovative structural materials able to withstand much higher temperatures and dpa; Reversibility (from burner to breeder and vice-versa); Capability to simulate, in a more reliable way, severe accident scenarios; Reduction of design uncertainties in all fields (and in particular in the area of safety analysis of postulated accident scenarios) with the use of well qualified advanced simulation tools (e.g. multi-physics and multi-scale codes), and innovative validation experiments. 9
Areas for International Cooperation Create an effective platform for exchange of information and lessons learned; Carry out focused R&D activities on crucial issues; Agree and converge on safety approaches, design criteria and guidelines at the international level; Share (expensive ) experimental facilities; Develop, verify and validate advanced simulation tools through experimental benchmarking; Provide cutting-edge opportunities for education and training; Collect, retrieve, preserve and make available existing documents, data and information on fast reactors (i.e. guarantee knowledge preservation on fast reactors). 10
Programmatic Areas in Support of FRs 1. Exchange of information 2. Modelling & Simulation and benchmarking activities for the V&V of nuclear codes for FRs 3. LMFR Technology 4. Safety 5. Education & Training 6. Knowledge Preservation 7. Cooperation with other international organizations
The Technical Working Group on Fast Reactors (TWG-FR) Members of the Technical Working Group on Fast Reactors Full Members Belarus Brazil China France Germany India Italy Japan Kazakhstan Korea, republic of Netherlands Russian Federation Slovakia Sweden Switzerland Ukraine UK USA European Commission OECD/NEA Observers Argentina Belgium Czech Republic Mexico Romania Spain Generation-IV International Forum (GIF) 48 th Annual Meeting of the TWG-FR IPPE, Obninsk, Russia 25-29 May 2015 12
Recent TECDOCs on Results of Experimental Benchmark Analyses for FR 13
Recent Publications on Fast Reactor Technology
4. Safety 15
Safety CRP on radioactive release from the PFBR under severe accident conditions Safety Design Criteria and Guidelines for GENIV SFR (GIF) Annual -GIF Workshop on safety of SFR Possible extension of the previous two activities to LFRs Technical Meeting on Passive Shutdown Systems for LMFR Vienna, 20-22 October 2015 Two new studies on relevant aspects of FR safety to be launched in 2016: Update of the -TECDOC-1180 Unusual occurrences during LMFR operation (proceedings of a TM held in November 1998) LMFR Passive Shutdown Systems
CRP on Radioactive Release from the Prototype Fast Breeder Reactor under Severe Accident Conditions Proposals Received so far Canada: UOIT France: IRSN & CEA India: IGCAR Russian Federation: IBRAE China: CIAE, NCEPU, XJTU Germany: KIT Korea, Republic of: KAERI Spain: CIEMAT USA: TerraPower i. 0 ms ii. 50 ms iii. 100 ms iv. 150 ms v. 200 ms Numerical simulation of core bubble expansions during a CDA (100 MJ) Reference design for the safety analysis: 500 MWe pool type PFBR Evaluation of: Transport of fission products (FP), Na and other radioactive materials from the melted core to the cover gas Ejection of FP, Na, fuel particles through the penetrations of the top shield reactor structure directly into the containment system and indirectly through the argon cover gas system Transport of fission products and other radioactive materials through the different containment compartments under various thermodynamics conditions First RCM: Vienna, 23-26 February 2016
1 st GIF- Workshop on Safety of SFR - 2010 Title: -GIF Workshop on Safety Aspects of Sodium Cooled Fast Reactors Dates : 23 25 June 2010 Venue: Vienna, HQ Main topic: operating experience and safety fundamental of SFR designs 18
2 nd GIF- Workshop on Safety of SFR - 2011 http://www.iaea.org/inpro/cooperation/second_-gif_ws_on_sfrs/ 19
3 rd GIF- Workshop on Safety of SFR Feb. 2013 http://www.iaea.org/nuclearpower/meetings/2013/2013-02-26-02-27-tm-sfr.html 20
3 rd GIF- Workshop on Safety of SFR Feb 2013 Presentation and preliminary discussion of the interim report of the GIF SDC_SFR Phase 1 Report SDC adopted in India for PFBR and next generation FBRs US Standard ANS 54.1 European project SARGEN_IV Safety design approaches for GEN-IV SFRs 21
4 th GIF- Workshop on Safety of SFR: 10-11 June 2014 http://www.iaea.org/nuclearpower/meetings/2014/2014-06-10-06-11-tm-nptd.html 22
4 th GIF- Workshop on Safety of SFR June 2014 Status of review of the SDC_SFR Phase 1 Report by Regulators and International Organizations: Status of the international review (GIF, Nakai & Okano) Comments from SEC_NRS (Russia) and USNRC Implementation of current SDC_SFR by the designers of innovative SFRs concepts: CIAE, CEA/AREVA/EDF, IGCAR, BHAVINI, JAEA, KAERI, OKBM, US-ORNL, GE Status of SFR_SDC Phase 2 development and implementation of specific SDC (practical elimination of accident situations, design extension conditions, sodium void reactivity effect) Introduction to Safety Design Guidelines (GIF, Nakai & Okano) Examples of implementation from CIAE, CEA/AREVA/EDF, IGCAR/BHAVINI, JAEA, ANL, EC 23
5 th GIF- Workshop on Safety of SFR: 23-24 June 2015 https://www.iaea.org/nuclearpower/meetings/2015/2015-06-23-06-24-nptds.html 24
5 th GIF- Workshop on Safety of SFR: 23-24 June 2015 Continuous in-depth discussions on the development and application of SFR Safety Design Criteria and Guidelines (SDC/SDG) Specific topics: Discuss the updated SDC report considering the comments on SDC phase 1 report from external organizations (USNRC,, IRSN) Review and discuss the GIF report "Safety Design Guidelines on Safety Approach and Design Conditions" Share information on implementation of SDC/SDG by the designers of innovative SFR concepts (ASTRID, JSFR, PSFR, BN-1200, ESFR) Participants: NE & NS, Canada (CNSC), France (CEA, AREVA, EdF, IRSN), Germany (GRS), India (IGCAR, BHAVINI), Japan (JAEA), Republic of Korea (KAERI, KEPCO), Russian Federation (IPPE, OKBM, SEC NRS), USA (ANL, INL, NRC, GE HITACHI), OECD/NEA, EC/JRC 25
Passive Shutdown Systems in SFR_SDC Phase 1 Report Principles of the SDC formulation - Particular issues for SFR: Enhanced Safety Approach: Passive system for shutdown & cooling Fundamental orientations on safety: Safety for design extension conditions:.due consideration for applying passive design measures, by utilizing/enhancing favourable safety features specific to the Generation-IV SFR system, will also be required for design extension conditions. Feedback from past experience in this field will be used to improve reliability Utilisation of passive safety features:.using passive and inherent safety features of the design should allow termination of accidents or mitigation of consequences of a design extensions conditions, even in postulated failure of active safety systems Safety approach of the Generation-IV SFR systems: SFR design for design extension conditions:.in order to prevent core damage, the design may make use of passive or inherent reactor shutdown capabilities. Lessons Learned from Fukushima Dai-ichi NPP Accidents: Enhancing passive safety functions will reduce the dependency on power supplies, and will also be effective as a measure against power loss 26
Passive Shutdown Systems in SFR_SDC Phase 1 Report Criterion 7: Application of defence in depth: The design shall consider the benefit of implementing passive safety features for shutdown and cooling Criterion 25: Single failure criterion The design shall take due account of the failure of a passive component, unless it has been justified in the single failure analysis with a high level of confidence that a failure of that component is very unlikely and that its function would remain unaffected by the postulated initiating event Criterion 46: Reactor shutdown: The means for shutting down the reactor shall consist of at least two diverse and independent systems. For design extension conditions, passive or inherent reactor shutdown capabilities shall be provided to prevent severe core degradation and to avoid re-criticality in the long run 27
Passive Shutdown Systems in SFR_SDC Phase 1 Report Glossary: A passive safety system for reactor shutdown is activated by responding directly to the changes of plant conditions (e.g. coolant temperature and/or pressure) and also operated by natural forces/phenomena (e.g. gravitational drop of absorber materials, enhancement of neutron leakage and/or moderation), which do not depend on protection system and safety system support features Appendix: Guide to Utilization of Passive/Inherent Features 28
Rationale of this TM A major focus of the design of modern fast reactor systems is on inherent and passive safety Inherent safety means that the reactor design is such that the plant remains in a safe condition solely on the basis of the laws of nature; these laws ensure that all performance characteristics remain within safe bounds under all conceivable circumstances. The definition of passive safety is broader, and implies that no human intervention, no triggering signals and no supply of external energy are required for the reactor to remain in a safe condition. Inherent and passive safety features are especially important when active systems such as the emergency shutdown (scram ) systems for reactor shutdown are not functioning properly. 29
Challenges for Designers of Passive Shutdown Systems Speed, reliability and predictability of actuation during accident scenarios Testability during operation Lifetime and performance degradation issues Impact on core operation Impact on neutron economy and core design Accurate modelling in safety analysis Necessary qualification programmes Costs 30
Objectives of the TM Promote the exchange of information on projects and programmes dealing with passive shutdown systems for liquid metal cooled fast reactors at the national and international level Present and review advanced safety shutdown system concepts and their impact on core performance, operation, cost and safety Identify transients for which the safety shutdown systems are efficient and analyse the transients for which these systems could have a negative behaviour Discuss the accuracy of the simulation tools used in the analysis of safety shutdown systems and any uncertainties that may affect these Identify needs and priorities for the improvement of system design and modelling to be taken into account in the further development of safety shutdown systems Discuss and propose international initiatives aimed at the V&V&Q of simulation codes used for the analysis of safety shutdown systems 31
Expected Outputs of the TM Exchange information on passive shutdown systems for fast reactors; Elaborate recommendations to the for future joint efforts and coordinated research activities in the field Agree content and structure of an Technical Document (type to be decided at this meeting) based on the papers submitted by participants + other background documentation 32
NES - Nuclear Energy Series The Department of Nuclear Energy produces documents in the NE series regarding the application of nuclear technology that provides analysis for and advice, assistance and guidance to the Member States. These documents represent developments and achievements in their subject areas within the nuclear industry and research community, based upon input from international experts Need to establish a clear relationship between the NE series documents and the existing series of Safety Standards and safety documents published by the Department of Nuclear Safety and Sec. NE documents presenting the best practices, state-of-the-art and recommendations in the use/development of technology and in management provide one of the bases for the development of the Safety Standards In order to check NE documents consistency with the current Safety Standards, NS is represented on the NE Document Coordination Team (DCT) and should review NES at various stages of development 33
Nuclear Energy Series: Criteria Broad interest, Will fit into the NE Series structure, and Contain an recommendation, guidance, or Member States good practices/lessons learned 34
Nuclear Energy Series: Categories Basic Principles Objectives Guides Technical Reports 35
http://www.iaea.org/nuclearpower/fr/ Thanks for Your Attention! Atoms for Peace 36