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Viability of Inert Matrix Fuel in Reducing Plutonium Amounts in Reactors

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Viability of Inert Matrix Fuel in Reducing Plutonium Amounts in Reactors IAEA-TECDOC-1516 Viability of inert matrix fuel in reducing plutonium amounts in reactors August 2006 IAEA-TECDOC-1516 Viability of inert matrix fuel in reducing plutonium amounts in reactors August 2006 The originating Section of this publication in the IAEA was: Nuclear Fuel Cycle and Materials Section International Atomic Energy Agency Wagramer Strasse 5 P.O. Box 100 A-1400 Vienna, Austria VIABILITY OF INERT MATRIX FUEL IN REDUCING PLUTONIUM AMOUNTS IN REACTORS IAEA, VIENNA, 2006 IAEA-TECDOC-1516 ISBN 92–0–110506–1 ISSN 1011–4289 © IAEA, 2006 Printed by the IAEA in Austria August 2006 FOREWORD Reactors around the world have produced more than 2000 tonnes of plutonium, contained in spent fuel, as separated forms through reprocessing, or as weapons-grade material. The recycling of plutonium as uranium–plutonium mixed oxide fuel derives additional energy from this resource; however, it does not speedily reduce growing plutonium inventories. The use of inert matrix fuel (IMF) in the current generation of reactors would provide a means of reducing plutonium inventories. The reduction of the accumulated plutonium by the use of IMF is a subject of great interest in several Member States. Work on IMF to date has been investigating the feasibility and reactor strategies for utilizing these fuels. Another important application of IMF is the reduction of minor actinide content, with or without plutonium. IMF can be used both to manage plutonium inventories and to address the long term radiotoxicity of spent fuel by minor actinide reduction in today’s reactors. IMF materials are also being considered for generation-IV reactors. Further development is needed before commercial utilization of IMF. This report summarizes ongoing IMF work and strategies with emphasis on their advanced performance, and application to waste minimization in a closed fuel cycle. The status of the potential IMF candidates is reviewed. This publication encompasses several promising candidate IMF materials for both fast and thermal reactors, fabrication methods, status of irradiation tests, results of post-irradiation examination, modelling of IMF fuel performance, and system studies for identification of strategies for implementation of IMF. This report has been prepared based on two consultants meetings (held 13–16 May 2002 and 26–28 May 2003 in Vienna with the participation of experts from Canada, France, Japan, the Russian Federation, Switzerland and the USA) and additional input from other specialists. The contributions of all who gave valuable help in drafting the report (listed at the end of this publication) are greatly appreciated. The IAEA wishes to express its gratitude to C. Degueldre (Switzerland) for chairing the group of consultants. The review of the report by H.J. Matzke (who retired recently from the Institute for Transuranium Elements, European Commission) is appreciated. The IAEA officers responsible for this publication were F. Sokolov and H.P. Nawada of the Division of Nuclear Fuel Cycle and Waste Technology. EDITORIAL NOTE The use of particular designations of countries or territories does not imply any judgement by the publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and institutions or of the delimitation of their boundaries. The mention of names of specific companies or products (whether or not indicated as registered) does not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement or recommendation on the part of the IAEA. CONTENTS 1. OVERVIEW .................................................................................................................... 1 1.1. Background........................................................................................................ 1 1.1.1. Definitions ............................................................................................. 3 1.1.2. Potential IMF application ...................................................................... 5 1.2. Goals and advantages ........................................................................................ 8 1.2.1. Economics.............................................................................................. 8 1.2.2. Ecological .............................................................................................. 8 1.2.3. Safety ..................................................................................................... 9 1.2.4. Proliferation resistance .......................................................................... 9 1.3. History (before 80’s) ....................................................................................... 10 1.4. Current programmes ........................................................................................ 10 1.5. R&D activities for IMF qualification .............................................................. 12 2. NATIONAL PROGRAMMES...................................................................................... 12 2.1. Canada ............................................................................................................. 12 2.1.1. Assessment of IMF candidates, SiC fuel fabrication and irradiation............................................................................................. 12 2.1.2. Reactor physics, safety assessments and waste management.............. 14 2.2. France .............................................................................................................. 17 2.2.1. Plutonium management and waste transmutation ............................... 18 2.2.2. IMF for reactors of Generation IV....................................................... 23 2.3. Japan ................................................................................................................ 24 2.3.1. Studies on the ROX-LWR system....................................................... 25 2.3.2. Basic studies........................................................................................ 29 2.4. Russian Federation .......................................................................................... 30 2.4.1. IMF fuel development and testing....................................................... 31 2.4.2. Studies on the IMF application............................................................ 33 2.5. Switzerland ...................................................................................................... 36 2.5.1. Zirconium nitride based IMFs ............................................................. 36 2.5.2. Zirconia based IMF.............................................................................. 36 2.6. United States of America................................................................................. 40 2.6.1. US advanced fuel cycle programme .................................................... 40 3. INTERNATIONAL PROGRAMMES.......................................................................... 44 3.1. Irradiations....................................................................................................... 44 3.1.1. Irradiation of plutonium inert matrix fuel for “once-through-then- out” option ........................................................................................... 44 3.1.2. Halden irradiations............................................................................... 45 3.1.3. IMF irradiation for EFTTRA............................................................... 46 3.1.4. Inert matrix fuel for transmutation in fast reactor................................ 46 3.2. Neutronic benchmarks..................................................................................... 47 3.3. IMF workshops................................................................................................ 50 4. RESULTS AND OUTLOOK ........................................................................................ 51 4.1. Homogeneous fuels......................................................................................... 52 4.1.1. Oxide solid solution fuels .................................................................... 52 4.1.2. Nitride solid solution fuels................................................................... 55 4.1.3. Metal alloy fuels.................................................................................. 55 4.2. Heterogeneous fuels ........................................................................................ 56 4.2.1. Cercer dispersion fuels......................................................................... 57 4.2.2. Coated particle dispersion fuels........................................................... 59 4.2.3. Cermet dispersion fuels ....................................................................... 60 4.2.4. Metmet dispersion fuels....................................................................... 61 4.3. Fuel safety performance .................................................................................. 62 4.3.1. Solid solution type fuel ........................................................................ 62 4.3.2. Cercer type fuel.................................................................................... 62 4.3.3. Cermet type fuel................................................................................... 63 5. CONCLUSION.............................................................................................................. 63 REFERENCES.......................................................................................................................
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