Euratom 7 th Framework Programme Collaborative Project Fast / Instant Release of Safety Relevant Radionuclides from Spent Nuclear Fuel

Transcription

1 Euratom 7 th Framework Programme Collaborative Project Fast / Instant Release of Safety Relevant Radionuclides from Spent Nuclear Fuel EURADISS 2012, Montpellier, F, th October 2012 Bernhard Kienzler, KIT-INE, Karlsruhe, D Alba Valls, AMPHOS21, Barcelona, E Volker Metz, KIT-INE, Karlsruhe, D Acknowledgement: The research leading to these results has received funding from the European Atomic Energy Community's Seventh Framework Programme (FP7/ ) under grant agreement no , the project.

2 Details on the CP EU Call: Type: Financial: Duration: Research activities in support of implementation of geological disposal (Fission ) Small/medium scale Collaborative Project 4,741,261 total costs 2,494,513 EU contribution 01. Jan Dec (3 years)

3 Definition of instant / fast release Project related definition or PA related definition RN release by matrix corrosion controlled by radiolysis, hydrogen, Cl-... gap large cracks grain boundaries initial (fast) release of RN controlled by chemistry, spatial distribution, burn-up, lin. power, close to surface rim grain boundaries along cracks (reactor operation) Definitions: PA term: instant release Experimental / lab related: fast release (for a specific fuel sample) controlled by: sample preparation, fragment size, presence of cladding, duration of experiments,...

4 Complex structure of spent fuel Cladding: C Gap region: C, I, Cs, Se, Tc Enriched rim: Pu Spent fuel Spent fuel fuel grains U, Pu, Ln, Sr fission gas bubbles Kr, Xe, I Grain boundaries C, I, Cs, Se, Tc Rim enriched with Pu -particles metallic precipitates Mo, Ru, Pd, Tc, Rh Ag, Cd, In, Sb, Sb oxide precipitates Rb, Cs, Ba, Zr, Nb Mo, Tc

5 Rationale of Previous EU projects (MICADO, NF-Pro, SFS,...) Improvement in understanding. o high burn-up UO 2, linear power, temperature, ramping,... Relationship FGR and release of non-gaseous FPs o gases, 135 Cs, 129 I, 14 C compounds, 79 Se, 99 Tc and 126 Sn. Grain boundary effects. Chemical speciation of relevant elements. Vision Report and SRA of the IGD-TP Key topic: Waste forms behaviour, in particular high burn-up spent UO 2 fuels. Recommendations by the End Users (kick off meeting) Definition of instant rapid fast release and delineation to long-term RN release processes. Up-scaling from lab sample to rod/assembly. Effect of geochemical conditions.

6 The Consortium (1) 1. Partners / Beneficiaries Subatech Hungarian Academy of Sciences, Centre for Energy Research 2. Associated Groups (AG) Groups participating at their own costs with specific RTD contributions or particular information exchange functions, or mobility measures (for European AGs only)

7 The Consortium (2) 3. End-user group: Representatives: Roles and Tasks within CP : Review the work program Review the scientific-technical progress and contributions to the proceedings Assess the project status and provide recommendations for the work program Review the plan for dissemination of the final results.

8 Project Events/Milestones Kick-off: 8-9 Feb Topical Sessions 1 st Annual Workshop: 9-11 Oct Scientific &Technical Output: 20 S&T To be published (KIT Scientific Report) Review by the EUG Reflection of end-user interests on the S&T contributions:... reflects fully the end user interests as defined in the SRA of the IGD-TP.... is a preparation work required to reflect the end user interests... presents methodological work required to reflect the end user interests... is relevant within the technical scope of the project.... is relevant for specific reporting, dissemination and communication purposes... reflects fully the end user interests as defined in your national program.

9 WP 1: Samples and tools Work Programme: 6 Workpackages Selection, characterization and preparation of and set-up of tools for handling and transportation of the highly radioactive material WP leader: Volker Metz (KIT) PWR BWR THTR / VVER Discharge Pellet Enrichment % % % Irradiation Burn-up GWd/t GWd/tU Cycles lin. Power average W/cm 160 W/cm W/cm FGR % %

10 WP 2: Gas release and rim and grain boundary diffusion WP leader: Detlef Wegen (JRC-ITU) Experimental determination of fission gas release Fuel Rod Drill V d ST 1 ST 2 Puncturing device V e1 V e2 Analysis Ne Vd = Drilling Chamber Ve1 = Expansion Chamber 1 Ve2 = Expansion Chamber 2 ST 1 = Storage Tank 1 ST 2 = Storage Tank 2 Ventilation Scheme of the fuel rod puncturing device. by JRC-ITU Experimental investigation of rim / grain boundary diffusion

11 WP 3: Dissolution based release WP leader: Karel Lemmens (SCK CEN) Dissolution based radionuclide release and to the extent possible the chemical speciation of the relevant isotopes. Partners: KIT-INE, JRC-ITU / CTM, PSI, Studsvik, EK (MTA), SCKCEN Agreement on experimental details to cover the whole range of conditions: Samples/sample preparation (powder pellets) Conditions (oxic anaerobic) Groundwater

12 WP3: Experimental details PSI Sample preparations: powder, fragments, pellets +/- cladding Atmospheric conditions Conditions PSI anoxic/oxic Studvik CTM: powder ITU: fragments KIT ITU/CTM SCKCEN Studsvik anoxic oxic oxic oxic INE: pellet / fragm. Leach media (simple to complex or buffer solution) borate Na + I - Cl - HCO - 3 Ca 2+ Mg 2+ SO 2-4 ph PSI 28 > KIT ITU/CTM SCKCEN Studsvik

13 WP4: Modelling WP leader: Joan de Pablo (CTM/UPC) Aims of the conceptual and numerical modelling Quantify the fast/instant release fraction of fission products. FP migration along the grain boundaries and fractures, effects of defects in the cladding on the fast release. Up-scaling from fragments/pellets to fuel assemblies. Modeling the chemical state of relevant elements. Delineation from matrix dissolution process.

14 Modelling Approach: The Reference Pellet & sub-µm scale model The Idealised Reference Pellet: 13.5 mm high and 8.19 mm in diameter Mean crack aperture of 20 µm Easy to implement aperture(r, h) From Willford (1984) From Oguma (1983) Additional 1D calculations wrt the sub-μm cracks 1 mm reference distance Arbitrary crack aperture of 0.1 µm Porous-equivalent approach

15 WP5: Knowledge, reporting and training: WP leader: Alba Valls (AMPHOS21) Knowledge management and documentation of the State-of-the- Art with regular up-dating. Stepwise build-up of scientific-technical reporting Dissemination and Communication, Training Please see the project webpage

16 (Contract Number:295722) DELIVERABLE (D-N :5.1) State of the art report Available in the Project website Uploaded in the official web Author(s): KIT/AMPHOS21 Reporting period: e.g. 01/01/ /06/2013 Date of issue of this report: 30/06/2012 Start date of project: 01/01/2012 Duration : 36 Months Project co-funded by the European Commission under the Seventh Euratom Framework Programme for Nuclear Research & Training Activities ( ) Dissemination Level PU Public X RE Restricted to a group specified by the partners of the [] project CO Confidential, only for partners of the [] project

17 D5.1. Table of contents 0. INTRODUCTION 1. DESCRIPTION OF THE FUEL UO 2 PELLET ENRICHMENT AND POSSIBLE BURN-UP FUEL RODS FUEL ELEMENTS / ASSEMBLIES 2. IRRADIATION INDUCED PROCESSES IN UO 2 TEMPERATURE OF THE FUEL IN A REACTOR 3. OPTIMIZATION OF NUCLEAR FUEL (UO 2 ) 4. MODELING TOOLS FOR FUEL PERFORMANCE gap and grain boundary release: 5. DISPOSAL OF SPENT NUCLEAR FUEL 80 PWR fuel experiments CANISTER CONCEPTS 20 BWR fuel experiments WATER CONTACT TO THE FUEL IN THE CASKS 20 MOX fuel experiments WATER ACCESS TO THE SPENT FUEL 6. PREVIOUS INVESTIGATIONS ON FAST/INSTANT RELEASE 7. SELECTION OF MATERIALS WITHIN FIRST-NUCLIDES 8. OBJECTIVES OF FIRST-NUCLIDES IN THE CONTEXT OF PREVIOUS INVESTIGATIONS 9. REFERENCES APPENDIX I: MANUFACTURERS APPENDIX II: CANISTER/DISPOSAL CONCEPTS

18 WP6: Coordination and management WP leader: Bernhard Kienzler (KIT) Thank you