State-of-the-art Report on the Progress of Nuclear Fuel Cycle Chemistry

304 Pages·2018·18.71 MB·English

by  coll.

Nuclear Science
2018
S
tate-of-the-Art Report
on the Progress of Nuclear
Fuel Cycle Chemistry

Nuclear Science
State-of-the-Art Report on the Progress
of Nuclear Fuel Cycle Chemistry

© OECD 2018
NEA No. 7267
NUCLEAR ENERGY AGENCY
ORGANISATION FOR ECONOMIC CO-OPERATION AND DEVELOPMENT
ORGANISATION FOR ECONOMIC CO-OPERATION AND DEVELOPMENT
The OECD is a unique forum where the governments of 35 democracies work together to address the
economic, social and environmental challenges of globalisation. The OECD is also at the forefront of
efforts to understand and to help governments respond to new developments and concerns, such as
corporate governance, the information economy and the challenges of an ageing population. The
Organisation provides a setting where governments can compare policy experiences, seek answers to
common problems, identify good practice and work to co-ordinate domestic and international policies.
The OECD member countries are: Australia, Austria, Belgium, Canada, Chile, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Israel, Italy, Japan,
Korea, Latvia, Luxembourg, Mexico, Netherlands, New Zealand, Norway, Poland, Portugal, Slovak
Republic, Slovenia, Spain, Sweden, Switzerland, Turkey, the United Kingdom and the United States.
The European Commission takes part in the work of the OECD.
OECD Publishing disseminates widely the results of the Organisation’s statistics gathering and
research on economic, social and environmental issues, as well as the conventions, guidelines and
standards agreed by its members.
This work is published on the responsibility of the Secretary-General of the OECD.
NUCLEAR ENERGY AGENCY
The OECD Nuclear Energy Agency (NEA) was established on 1 February 1958. Current NEA
membership consists of 33 countries: Argentina, Australia, Austria, Belgium, Canada, the Czech
Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Korea,
Luxembourg, Mexico, the Netherlands, Norway, Poland, Portugal, Romania, Russia, the Slovak
Republic, Slovenia, Spain, Sweden, Switzerland, Turkey, the United Kingdom and the United States.
The European Commission also takes part in the work of the Agency.
The mission of the NEA is:
–to assist its member countries in maintaining and further developing, through international co-
operation, the scientific, technological and legal bases required for a safe, environmentally sound
and economical use of nuclear energy for peaceful purposes;
–to provide authoritative assessments and to forge common understandings on key issues as
input to government decisions on nuclear energy policy and to broader OECD analyses in areas
such as energy and the sustainable development of low-carbon economies.
Specific areas of competence of the NEA include the safety and regulation of nuclear activities,
radioactive waste management, radiological protection, nuclear science, economic and technical
analyses of the nuclear fuel cycle, nuclear law and liability, and public information. The NEA Data
Bank provides nuclear data and computer program services for participating countries.
This document, as well as any data and map included herein, are without prejudice to the status of or sovereignty
over any territory, to the delimitation of international frontiers and boundaries and to the name of any territory,
city or area.
Corrigenda to OECD publications may be found online at: www.oecd.org/publishing/corrigenda.
© OECD 2018
You can copy, download or print OECD content for your own use, and you can include excerpts from OECD publications, databases and
multimedia products in your own documents, presentations, blogs, websites and teaching materials, provided that suitable
acknowledgement of the OECD as source and copyright owner is given. All requests for public or commercial use and translation rights
should be submitted to [email protected]. Requests for permission to photocopy portions of this material for public or commercial
use shall be addressed directly to the Copyright Clearance Center (CCC) at [email protected] or the Centre français d'exploitation du
droit de copie (CFC) [email protected].
FOREWORD
Foreword
Under the guidance of the Nuclear Energy Agency (NEA) Nuclear Science Committee
(NSC), and the mandate of the NEA Working Party on Scientific Issues of the Fuel Cycle
(WPFC), the Expert Group on Fuel Recycling Chemistry (EGFRC) was established to
perform technical assessments of separation processes relevant to recycling technologies
for spent nuclear fuel and assessments of separation processes in applications related to
the current and future nuclear fuel cycles. The expert group was also mandated to
provide recommendations for collaborative international efforts towards the
development of further separation processes.
This report presents a comprehensive state of the art on current developments in
various separation technologies. It was written in the form of an international review of
the different separation processes developed – or under development – in separation
chemistry within a number of NEA member countries (France, Japan, Korea, Russia, the
United Kingdom and the United States, as well as the European Union).
Acknowledgements
The NEA Secretariat would like to extend its sincere gratitude to the members of the
EGFRC for their contributions to this report, as well as for the valuable time and effort
dedicated to this field of work. Special thanks go to P. Baron (France), Chair of the expert
group. Thanks are also extended to E. Collins (United States) for his review and helpful
suggestions.
3
STATE-OF-THE-ART REPORT ON THE PROGRESS OF NUCLEAR FUEL CYCLE CHEMISTRY, NEA No. 7267, © OECD 2018

TABLE OF CONTENTS
Table of contents
List of abbreviations and acronyms ..........................................................................................13
Executive summary ......................................................................................................................19
1. Introduction ...............................................................................................................................23
2. Progress of separation technology and current achievements ........................................25
2.1. Head-end processing ..........................................................................................................25
2.2. Hydrometallurgy .................................................................................................................45
2.3. Pyrochemical processess .................................................................................................140
3. Process criteria ........................................................................................................................227
3.1. Introduction .......................................................................................................................227
3.2. Feeds to the recycling plant(s) ........................................................................................227
3.3. Products required from the recycling plant(s) ..............................................................229
3.4. Performance criteria required from the recycling plant(s) .........................................231
3.5. Constraints placed on the recycling plant(s) ................................................................231
3.6. Nonproliferation requirements for recycling components of
spent nuclear fuel (SNF) ..................................................................................................233
3.7. Choice of separation process ..........................................................................................238
3.8. Conclusions .......................................................................................................................238
4. Comparison of chemical processes .....................................................................................241
4.1. Introduction .......................................................................................................................241
4.2. Head-end processes ..........................................................................................................243
4.3. Aqueous processes ...........................................................................................................248
4.4. Pyrochemical processes ...................................................................................................271
4.5. Conclusions .......................................................................................................................277
5. Perspectives for future R&D ..................................................................................................281
5.1. France .................................................................................................................................281
5.2. Japan ...................................................................................................................................282
5.3. Korea ...................................................................................................................................283
5.4. Russia ..................................................................................................................................284
5.5. United Kingdom ................................................................................................................286
5.6. United States .....................................................................................................................288
6. Conclusions ..............................................................................................................................293
List of Contributors .....................................................................................................................297

5
STATE-OF-THE-ART REPORT ON THE PROGRESS OF NUCLEAR FUEL CYCLE CHEMISTRY, NEA No. 7267, © OECD 2018
TABLE OF CONTENTS
List of figures
ES 1. Summary of TRLs for head-end processes ..................................................................20
ES 2. Summary of TRLs for aqueous processes ....................................................................20
2.1. Radioactivity of 4% 235U – 40 GWd/tHM, under three scenarios ...............................26
2.2. Westinghouse PWR fuel assembly ...............................................................................28
2.3. Mechanical head-end process for the spent fuel PWR ..............................................29
2.4. Oxidative decladding efficiency according to variation of rod-cut length
and burn-up .....................................................................................................................31
2.5. Decladding efficiency according to variation of burn-up ..........................................31
2.6. “Mini Khrust” pilot set-up (heater, ampoule for spent nuclear fuel
and cork are observed) ...................................................................................................32
2.7. View of zirconium cladding before and after treatment ...........................................33
2.8. Broken cladding ...............................................................................................................33
2.9. Voloxidised uranium dioxide nuclear fuel ..................................................................33
2.10. Typical head-end operations where zirconium recovery may be integrated ........35
2.11. Interfacing zirconium recovery from cladding with tubing manufacture .............36
2.12. Standard dry oxidation pre-treatment process with off-gas treatment .................37
2.13. A rotary voloxidiser and UO granules .......................................................................39
2+x
2.14. Off-gas treatment system for DUPIC sintering furnace in DFDF and gamma
spectroscopy measurement results of the fly ash filter ............................................42
2.15. Equipment for engineering-sclae tests in PRIDE facility ...........................................42
2.16. Advanced head-end operations ....................................................................................43
2.17. Structure of DEHiBA........................................................................................................46
2.18. Aqueous and organic concentration profiles of nitric acid and uranium ..............47
2.19. Flowsheet for the Ganex 1st cycle hot test ...................................................................47
2.20. Photo of the extraction section of mixer-settlers .......................................................48
2.21. Experimental and calculated profiles of uranium and technetium
concentrations in aqueous and organic phases for the three sections ..................48
2.22. Schematic flow of the NEXT process ...........................................................................50
2.23. Sellafield Thorp plant – solvent extraction flowsheet ...............................................51
2.24. COEXTM process ................................................................................................................53
2.25. Representation of the co-crystallised U(IV)-Pu(III) mixed oxalate structure ..........54
2.26. NUEX process solvent extraction flowsheet ...............................................................55
2.27. Generic flowsheet layout for Np extraction in the first cycle (HA/HS contactor) ..56
2.28. Schematic of single cycle Advanced PUREX process suitable for Gen IV
fuel reprocessing .............................................................................................................58
2.29. UREX+ co-decontamination process ............................................................................59
2.30. Calculated plutonium concentration factors using the SEPHIS code ......................61
2.31. Flowsheet for VVER-1000 SNF reprocessing using the basic “simplified
PUREX process’’ ...............................................................................................................64
2.32. Electron microscope image of a mixed oxide sample at different
magnifications using the back-scattered electron mode ..........................................66
2.33. Image of the uranium oxide sample after denitration ..............................................66
2.34. Block schematic diagram of REPA process ..................................................................68
2.35. The dependence of U/Pu ratio in the aqueous flow of Pu leaving the
washing zone on the ratio of phase flows in the zone ..............................................70
2.36. The laboratory facility for actinide melting showing 1 – a thermocouple
in a glass pocket, 2 – an evaporator, 3 – a direct condenser and 4 – a
solution of actinide nitrates ..........................................................................................70
2.37. Absorption spectra of melts ..........................................................................................71
6
STATE-OF-THE-ART REPORT ON THE PROGRESS OF NUCLEAR FUEL CYCLE CHEMISTRY, NEA No. 7267, © OECD 2018
TABLE OF CONTENTS
2.38. The solubility isotherms of the system UO (NO ) -HNO -H O and location
2 3 2 3 2
of the working line zone (A) of the crystallisation process of the UNH ..................73
2.39. Crystals of (U,Pu,Np)O (NO ) •6H O ...............................................................................73
2 3 2 2
2.40. Relationship between the ratio [NU]/[HNO ] in mother liquor from
3
temperature along working line with k=1.6. ...............................................................74
2.41. Crystals of (a) UO (NO ) •6H O and (b) (U,Pu)O (NO ) •6H O .......................................75
2 3 2 2 2 3 2 2
2.42. Crystals (U,Pu)O (NO ) •6H O with an increased content of plutonium ..................76
2 3 2 2
2.43. SANEX-BTBP process flowsheet tested at the ITU (Germany) on a genuine
“An(III)+Ln(III)” feed .........................................................................................................83
2.44. Calculated and experimental concentration profiles for 241Am ...............................84
2.45. Calculated and experimental concentration profiles for 244Cm ...............................84
2.46. The DIAMEX-SANEX/HDEHP process principle ..........................................................85
2.47. DIAMEX-SANEX/HDEHP process flowsheet tested at the CEA Marcoule
on a genuine PUREX raffinate .......................................................................................86
2.48. Structural formula of DGA compounds .......................................................................87
2.49. Extraction of nitric acid with (a) polar fluorinated diluents; (b) 0.1 mol/L
TODGA in polar fluorinated diluents ...........................................................................90
2.50. The dependency of (a) Am and (b) Eu distribution ratios values on
nitric acid concentration. Solvent – 0.01 mol/L TODGA in diluent ..........................91
2.51. The dependency of (a) Am and (b) Eu distribution ratios on TODGA
concentration in diluents with extraction from 1 mol/L HNO ................................92
3
2.52. Extraction of lanthanide ions from 1 mol/L HNO3 into solutions of
0.01 mol/L TODGA in diluents: F-3, DDFHME and Formal-2 .....................................93
2.53. Chemical Structures of TODGA, T2EHDGA and HEH[EHP] ........................................94
2.54. Distribution of Ln and Am as a function of diamide type; Aqueous phase:
3 mol/L HNO ; solvent: 0.02 mol/L CCD + 0.01 mol/L DPA in FS-13 ..........................94
3
2.55. Structures of heterocyclic amides ................................................................................95
2.56. An-Ln extraction using 0.1 mol/L dyp-7 in F-3 from 3 mol/L HNO .........................96
3
2.57. The chemical structures of (a) CMPO and (b) HDEHP ................................................97
2.58. Americium (III) distribution ratios for extraction by 0.2 mol/L CMPO +
1.4 mol/L TBP in normal paraffin hydrocarbons [36] .................................................97
2.59. The TRUEX solvent extraction flowsheet ....................................................................98
2.60. The TALSPEAK solvent extraction flowsheet..............................................................99
2.61. The Advanced TALSPEAK solvent extraction flowsheet ...........................................99
2.62. GANEX process under development at CEA (France) ..............................................101
2.63. EURO-GANEX flowsheet tested with spent fuel .......................................................102
2.64. Structure of zirconium salt of dibutylphosphoric acid (ZS of HDBP).....................104
2.65. The process flowsheet used in treating real HLW ...................................................105
2.66. Adsorbent porous silica particles coated with styrene-divinylbenzene
polymer ..........................................................................................................................106
2.67. Chemical structures of extractants examined in the development of
separation process by extraction chromatography in JAEA ...................................107
2.68. Chromatogram of simulated raffinate using CMPO/SiO -P adsorbent ..................107
2
2.69. Chromatogram of the simulated raffinate using TODGA/SiO -P adsorbent ........108
2
2.70. Block schematic diagram of CARBEX-process ..........................................................110
2.71. Dependency of U(VI)/Cs separation factors (SF) as a function of
concentrations of U(VI) and Cs in extraction raffinates ..........................................112
2.72. Chlorinated cobalt dicarbollide, CCD, and polyethylene glycol, PEG ....................115
2.73. Extraction flowsheet for reprocessing of HLW with the use of ChCoDiC
at industrial facility 35U in “Mayak” ............................................................................115
2.74. Flowsheet of the CSSEX process implemented on a highly active
DIAMEX raffinate solution at the CEA Marcoule ......................................................117
2.75. Calix-crown R14 for Cs and DtBuCH18C6 for Sr .......................................................117
7
STATE-OF-THE-ART REPORT ON THE PROGRESS OF NUCLEAR FUEL CYCLE CHEMISTRY, NEA No. 7267, © OECD 2018
TABLE OF CONTENTS
2.76. Small scale adsorption tests for Cs and Sr separation with a genuine HLLW .....118
2.77. Molecular structures of the cesium and strontium extractants and the
Cs-7SB modifier used in the FPEX process solvent ..................................................119
2.78. Flowsheet of the FPEX process ....................................................................................119
2.79. Structure of sodium silicotitanate (TAM5) showing the parallel channels ..........124
2.80. A section of TAM5 structure showing the Ti clusters linked with
4
tetrahedral silicates ......................................................................................................124
2.81. Structure of sodium titanate .......................................................................................125
2.82. Cubic crystal structure of potassium cobalt hexacyanoferrate (K2CoFe(CN)6) ...126
2.83. Conceptual flow diagram of separation facility at INTEC .......................................127
2.84. Structures of naturally occurring zeolites .................................................................128
2.85. Structure of Type A zeolite ..........................................................................................129
2.86. Flowsheet of 4-group partitioning process developed by JAEA ..............................130
2.87. Density and crush strength of zeolite-cement composites ....................................131
2.88. Zeolite-cement composites with increasing waste loadings .................................131
2.89. Simplified process diagram for SIXEP, Sellafield, UK ..............................................133
2.90. Simplified flow sheet of the IVO-CsTreat System ....................................................133
2.91. Low active effluent treament at the EARP, Sellafield, UK .......................................134
2.92. Three possible strategies for Am/Cm separation .....................................................136
2.93. Three-step strategy for minor actinide separation ..................................................137
2.94. Am-Cm partitioning hot test performed on surrogate solution in
ATALANTE facility ........................................................................................................138
2.95. ExAm process flowsheet tested in 2010 to recover the sole Am(III) from
genuine PUREX raffinate ..............................................................................................139
2.96. Chromatogram of Am and Cm separation by ion exchange using
tertiary pyridine-type resin .........................................................................................140
2.97. A schematic block diagram for the treatment of contaminated uranium ...........145
2.98. Schematic process diagram for electrorefining ........................................................145
2.99. Process diagram for metal fuel cycle and for oxide fuel treatment ......................147
2.100. Pyrochemical reprocessing flow for spent oxide fuels ............................................149
2.101. Cathode basket and uranium metals reduced ..........................................................149
2.102. Engineering-scale electrorefining test .......................................................................150
2.103. Molten salt transport test ............................................................................................151
2.104. Schematic diagram of scrubbing system of waste salt and the
engineering scale test equipment ..............................................................................151
2.105. Reduction potentials of some actinides and lanthanides on
different cathodic materials ........................................................................................154
2.106. Process scheme for the electrorefining of metallic fuels An - actinides,
FP - fission products, Al - aluminum .........................................................................155
2.107. Cyclic voltamogram of U Pu Zr Am Ln on W and Al wires ................................156
61 22 10 2 5
2.108. Principle of the exhaustive electrolysis process .......................................................157
2.109. Schematic layout of an electroreduction process developed by CRIEPI/ITU ........158
2.110. Reduced fuel particles of irradiated MOX fuel particles (43 GWd/tHM);
section of cut basket .....................................................................................................159
2.111. Chemical reductive extraction diagram ....................................................................161
2.112. Cyclic Voltammetry on W electrode (SWE=0.16 cm2) in LiF-CaF -AmF ([AmF ]
2 3 3
= 1.5510-2 mol/kg) at 780°C; v=0,1V/s; Pt reference electrode; CE: graphite ..........163
2.113. Square Wave Voltammetry on W electrode (SWE=0.16 cm2) in
LiF-CaF-AmF-NdF ([AmF] = 1.5510-2 mol/kg, [NdF] = 5.710-2 mol/kg)
2 3 3 3 3
at 780°C; Pt reference electrode; CE: graphite...............................................................164
2.114. Combination of nitride fuel and pyro-electrochemical process based
on double-strata fuel cycle concept ...........................................................................166
8
STATE-OF-THE-ART REPORT ON THE PROGRESS OF NUCLEAR FUEL CYCLE CHEMISTRY, NEA No. 7267, © OECD 2018