Research and development needs in a step-wise process for the nuclear waste programme in Sweden

Transcription

1 Research and development needs in a step-wise process for the nuclear waste programme in Sweden Ström A 1, Pers K 2, Andersson J 1, Ekeroth E 1, Hedin A 1 1 Swedish Nuclear Fuel and Waste Mgmt. Co. (SKB), Stockholm, Sweden 2 SKB International AB, Stockholm, Sweden contact of main author: anders.strom@skb.se

2 Outline of presentation Background Implementation plan Continued research and technology development Concluding remarks CNS Sep

3 Nuclear in Sweden 9 (12) operating reactor units at 3 sites ~ 40 % of electricity Operation since 1972/85 SFR; Final Repository for Shortlived Radioactive Waste Clab; Central Interim Storage Facility for Spent Nuclear Fuel

4 Management and disposal of radioactive waste and spent nuclear fuel Based on current planning from NPP s: Reference scenario During 2015 decisions have been made on a premature shutdown of four reactors (Oskarshamn 1-2, Ringhals 1-2). 60 years of operation for all remaining plants. Spent nuclear fuel Approx tonnes of spent fuel Approx canisters LLW and ILW From operation and decommissioning Approx m 3 short-lived waste Approx m 3 long-lived waste 4

5 Research, Development and Demonstration Programme 2016 Requirements according to the Nuclear Activities Act License holders for nuclear reactors should every 3 rd year submit a programme for research and development and other measures necessary for decommissioning of nuclear facilities and final disposal of nuclear waste The programme should provide an overview of all measures that might may be necessary and specify in more detail the measures that are intended to be implemented within at least six years The programme shall be submitted to Swedish Radiation Safety Authority (SSM) Has been in effect since

6 Outline of presentation Background Implementation plan Continued research and technology development Concluding remarks CNS Sep

7 Licensing review according to Nuclear Activities Act and Environmental Code SKB s applications One according to Environmental Code Two according to Nuclear Act Court hearings Review Approves or disapproves Decides Permit and conditions Approves Safety Report 7

8 Step-wise process and planning For establishing nuclear facilities, planning is based on the stepwise decision process in the Nuclear Activities Act and SSM regulations The safety analysis report (SAR) is central and should provide an overall view of how the safety of the facility is arranged in order to protect human health and the environment against nuclear accidents. The implementer needs to provide successively refined safety reports to the regulator. The planning and milestones related to decision steps in the form of applications and safety analysis reports determine when knowledge and development of the technology needs to have reached a certain level, while SSM s approval determines when SKB can commence construction and operation of the facilities. F-PSAR PSAR SAR 8

9 Future important milestones Low and intermediate level waste License review on-going for extension of SFR, technology development, detailed design in parallel Construction work for extension of SFR starts 2022, operation 2028 Interim storages for decommissioning waste established Safety evaluation of SFL repository concept 2018 Application to construct SFL approx 2030 Spent Nuclear Fuel License review of the KBS-3 system Technology development industrial operation Nuclear Fuel Repository planning for detailed design on-going, start construction 2020, trial operation 2030, regular operation 2032 Encapsulation Plant system design to start, start construction 2022, trial operation 2030, regular operation 2032 Planning for increased storage capacity at interim storage Clab. Safety concept established. Safety analysis reports (PSAR) for the KBS-3- system in progress 9

10 Outline of presentation Background Implementation plan Continued research and technology development Concluding remarks CNS Sep

11 Milestones KBS-3 12

12 R&D needs in relation to milestones - KBS-3 Before the start of construction of the Spent Fuel Repository and the encapsulation plant Preliminary Safety Report, PSAR will be updated with some of the material presented in the supplement to the application under the Nuclear Activities Act and the updates in the initial state as ongoing technology development lead to. The goal of technology development is to ensure that the technology needed to begin construction of the Spent Fuel Repository and the encapsulation portion of Clink, is available before the start of construction. Detailed design phase will essentially have been passed for all barrier systems, except for the parts that require in situ tests. For the Spent Fuel Repository this first regards characterization methods and techniques for the construction of the repository access. Construction start deposition area At the start of construction of the deposition area of the Spent Fuel Repository the design requirements for this must be established and therefore also the design and installation methods for the buffer, backfill and plugs need to be finished as well as methods for the host rock characterization and methodology for excavation of deposition tunnels. Control methods to be applied shall be verified. Before the trial operation Integration testing and commissioning tests need to need to be conducted in the nuclear fuel repository and be reported in the updated Safety Analysis Report (SAR) Before the routine operation of the KBS-3 system An updated safety analysis report, SAR, considering the experience of trial operation is needed F-PSAR PSAR SAR 13

13 Basis for continued research and technology development The need for an increased process understanding Judge the importance for post-closure safe o Remaining uncertainties o Less pessimistic assumptions The need for knowledge and competence around design, construction, manufacture and installation of the components From conceptual design to working facilities The need for knowledge and competence around inspection and testing verify that the barriers and components are produced and installed according to approved specifications and thereby satisfy the requirements 14

14 Example: Canister key R&D issues Post closure safety Corrosion (sulphides, ) Copper creep understanding the process and function of phosphorus Technology development Canister design should be verified in conformity with requirements, manufacturing methods verified, testing and control processes should be developed and prerequisites from qualification clarified. o Copper components and welding o Insert design, manufacturing and qualification Basis for canister production system and canister assembly facility Inspection and testing 16

15 Example: Buffer, backfill, closure key R&D issues Post closure safety Buffer erosion Sulphide production Homogenisation process Technology development needed in time for PSAR Basis for updated production reports for BBC, based on updated technical design requirements. Product and process mapping done. Preliminary quality plans written. Need for qualification clarified Technology development for detailed design of production facility Material Procurement Specification established (including material studies) Decision on pressing methodology Bentonite block manufacturing and control methods that works in industrial scale 17

16 Outline of presentation Background Implementation plan Continued research and technology development Concluding remarks CNS Sep

17 Concluding remarks The SKB RD&D Programme 2016 contains an overview of all the measures that may be necessary for treatment and final disposal of nuclear waste from Swedish nuclear reactors and SKB's facilities clarifies how research and technology development are justified and evaluated in a step-wise procedure on the basis of the measures planned presents a strategic plan for the research and development necessary to establish and implement future activities Published as SKB TR in December

18 Remaining challenges Licensing and acceptance SKB, regulator, local authorities and Government Going from theory to practice Industrialization Keeping public confidence

19 Thanks for your attention!