AL.NIKOLOV, D.POPOV NPP KOZLODUY

1. FISA'2006 - LONG-TERM RESEARCH AND TRAINING FOR SUSTAINABLE DEVELOPMENT IN THE NUCLEAR FIELD FOUNDED BY THE EUROPEAN COMMISSION AL.NIKOLOV, D.POPOV NPP KOZLODUY

2. ACKNOWLEDGEMENTS • Thanks to: • Ass.Prof. Dr.Sc.Eng.Iv. Ivanov from Technical University of Sofia- to have assured our attendance to FISA’06; • Prof. Aragones, UPM, Spain; G. Löwenhielm,SKI, Sweden; T. Shulenberg, FZK,Germany; prof.B. Bazargan-Sabet, INPL-Ecole des Mines de Nancy, France; J.-P. Massoud, EDF, France; D. Warin, CEA, France; J.-Y. Blanc,CEA, France; M. McDermott, NNC Ltd, GB; W. Raskob,FZK,Germany; J.-C. Micaelli, IRSN, France; J.Tuunanen, TVO, Finland- to have sent personally their presentations in FISA’06 • Mrs. M. Antoine, secretary in Unit J.4, DG RTD- to have sent web links to FP-6

3. FISA’06 : 13-16 March, Luxembourg • FISA=FIssion SAfety: The FISA covers the entire spectrum of reactor safety research and training/education in new nuclear fields, that was included in last EURATOM’ Framework Program FP-6. Up to 350 participants of old and new EU countries and EU candidates but also from USA, Switzerland, Russia, Ukraine, Korea, Japan, Turkey and others, not to mention international organisations, such as IAEA,OECD/NEA.

4. FISA’06 what expectations from? • EC expected from FISA conference to improve the common vision on how to tackle the challenges of common interest in view of the upcoming critical deadline of 2010-2020, when many nuclear installations will have to be replaced… …and also to examine the future nuclear alternatives

5. Energy needs of EU Community EU25 Growth of import dependency U3O8 spot prices since 1990 (Source: T.Abram, “Integration of niternational research in innovative GenIV system ..”, FISA’06) Source: J. Mišák, F. Pazdera, “Future prospects for European cooperation in nuclear safety research”,FISA’06

6. EURATOM FP-6 PROJECTS • KEEPING THE NUCLEAR OPTION OPEN; • NEED FOR DRASTIC DECREASE OF THE CARBON INTENSITY IN THE ECONOMY; • ADDRESSING THE CHALLENGES OF GLOBAL WARMING; • EMPHASIS ON THE SAFETY OF INSTALLATIONS AND OF DISTRIBUTION NETWORKS AND SECURITY OF SUPPLY EC Green Paper 8 March 2006 Source: J. Mišák, F. Pazdera, “Future prospects for European cooperation in nuclear safety research”,FISA’06

7. EURATOM FP-6 PROJECTSGeneration-IV Innovative Concepts 6 REACTOR SYSTEMS SELECTED BY GIF FOR FURTHER DEVELOPMENT (~2030): • Water-Cooled: • 1. Super-Critical Water Reactor (SCWR) • Gas-cooled: • 2.Very-High Temperature Reactor (VHTR) • 3.Gas-cooled Fast Reactor (GCFR) • Liquid Metal-Cooled • 4. Sodium cooled Fast Reactor (SFR) • 5. Lead Fast Reactor (LFR) /Pb-Bi cooled • Non-Classical • 6. Molten Salt cooled Reactor (MSR) • Features of Gen IV: • High Safety Level • Good Economy • 2.1. High efficiency (η~ up to 50%) • 2.2.Possibility to develop H2 industry • 3. Proliferation resistance (Minor Actinides)

8. EURATOM FP-6 PROJECTSGeneration-IV Innovative ConceptsGas Cooled Fast Reactor FEATURES • Lead-cooled by natural convection • Outlet temperature of the helium 850 C • Possible to: • deliver Electricity • deliver Hydrogen • From breeder to burner and recycling minor actinides. • closed fuel cycle for efficient conversion of fertile uranium and management of actinides • Reference reactor - 600-MWth/288-MWe using a direct Brayton cycle gas turbine for high thermal efficiency. The GCFR reference has an integrated, on-site spent fuel treatment and refabrication plant. • Through the combination of a fast spectrum and full recycle of actinides, the GCFR minimizes the production of long-lived radioactive waste.

9. EURATOM FP-6 PROJECTSGeneration-IV Innovative ConceptsGas Cooled Fast Reactor –cont’d • Fuel type: CERCER plate fuel - hold the potential to operate at very high temperatures and to ensure an excellent retention of fission products: • composite ceramic fuel, • advanced fuel particles, or • ceramic clad elements of actinide compounds. • Core configurations may be based on prismatic blocks, pin- orplate-based assemblies (TUD) . The GFR system is top-ranked in sustainability because of its closed fuel cycle and excellent performance in actinide management. It is rated good in safety, economics, and in proliferation resistance and physical protection CERCER plate fuel High power density ~ 100 MW/m^3

10. EURATOM FP-6 PROJECTSGeneration-IV Innovative ConceptsGas Cooled Fast Reactor – cont’d Development Strategy • Commercial electricity production plant • GFR 2400 MWth (modular 600 MWth) by ~2030 • ETDR (Experimental Technology Demonstrator Reactor) • 20-50 MWth, first GCFR at Cadarache, France • Separate project from 2008, decision to build 2012 • Contrasts earlier GCFR projects (direct to prototype/demo) • Synergies with HTR • Helium-gas cooled • High temperature materials and components • Benefit from FP6 RAPHAEL-IP/Gen IV VHTR

11. EURATOM FP-6 PROJECTSGeneration-IV Innovative ConceptsLCR - Lead Cooled (Fast) Reactor System FEATURES • Lead-cooled by natural convection, fast-neutron spectrum. Fuel = MOX • Outlet temperature of the helium 550 C up to 850 C depending on the advanced materials to be used. • Possible to: • deliver Electricity • deliver Hydrogen • deliver potable Water • Full actinide recycle fuel cycle with central or regional fuel cycle facilities • Options include a range of plant ratings, including a battery of 50-150 MWe that features a very long refueling interval (15-20 yr) with cassette core or replaceable reactor module, a modular system rated at 300-400 MWe, and a large monolithic plant option at 1200.

12. EURATOM FP-6 PROJECTSGeneration-IV Innovative ConceptsLCR - Lead Cooled (Fast) Reactor System – cont’d • Sustainability • - Resource utilization. Because lead is a coolant with very low neutron absorption and moderation, it makes possible an efficient utilization of excess neutrons and reduction of specific uranium consumption. Reactor designs can readily achieve a breeding ratio of about 1, and long core life and a high fuel burnup can be achieved. • Waste minimization and management. A fast neutron flux significantly reduces waste generation, Pu recycling in a closed cycle being the condition recognized by GEN IV for waste minimization. The capability of the LFR systems to safely burn recycled minor actinides within the fuel will add to the attractiveness of the LFR. • Economics. • Life cycle cost. The cost advantage features of the LFR must include low capital cost, short construction duration and low fuel and low production cost. The economic utilization of MOX fuel in a fast spectrum has been already demonstrated in the case of the SFR, and no significantly different conclusion can be expected for the LFR except from improvement due to the harder spectrum.

13. Because of the favorable characteristics of molten lead, it will be possible to significantly simplify the LFR systems in comparison with the well known designs of the SFRs, and hence to reduce its overnight capital cost, which is a major cost factor for the competitive generation of nuclear electricity. A simple plant will be the basis for reduced capital and operating cost. A pool-type, low-pressure primary system configuration offers great potential for plant simplification.

14. EURATOM FP-6 PROJECTSGeneration-IV Innovative ConceptsSCR - Sodium-Cooled (Fast) Reactor System SFR – Sodium-Cooled Fast Reactor System The Sodium-Cooled Fast Reactor (SFR) system features fast-neutron spectrum and a closed fuel cycle for efficient conversion of fertile uranium and management of actinides. A full actinide recycle fuel cycle is envisioned with two major options: One is an intermediate size (150 to 500 MWe) sodium-cooled reactor with uranium-plutonium-minor-actinide-zirconium metal alloy fuel, supported by a fuel cycle based on pyrometallurgical processing in collocated facilities. The second is a medium to large (500 to 1500 MWe) sodium-cooled fast reactor with mixed uranium-plutonium oxide fuel, supported by a fuel cycle based upon advanced aqueous processing at a central location serving a number of reactors. The outlet temperature is approximately 550°Cfor both. The primary focus of the R&D is on the recycle technology, economics of the overall system, assurance of passive safety, and accommodation of bounding events. The SFR system is top-ranked in sustainability becauseof its closed fuel cycle and excellent potential foractinide management, including resource extension. It israted good in safety, economics, and proliferationresistance and physical protection. It is primarilyenvisioned for missions in electricity production andactinide management. The SFR system is the nearesttermactinide management system. Based on the experiencewith oxide fuel, this option is estimated to bedeployable by 2015.

15. EURATOM FP-6 PROJECTSGeneration-IV Innovative ConceptsSCWR – Supercritical-Water-Cooled Reactor System The Supercritical-Water-Cooled Reactor (SCWR )system features two fuel cycle options: the first is an open cycle with a thermal neutron spectrum reactor; the second is a closed cycle with a fast-neutron spectrum reactor and full actinide recycle. Both options use a high-temperature, high-pressure, water-cooled reactor that operates above the thermodynamic critical point of water (22.1 MPa, 374°C) to achieve a thermal efficiency approaching 44%. The fuel cycle for the thermal option is a once-through uranium cycle. The fast-spectrum option uses central fuel cycle facilities based on advanced aqueous processing for actinide recycle. The fast-spectrum option depends upon the materials’ R&D success to support a fast-spectrum reactor. In either option, the reference plant has a 1700-MWepower level, an operating pressure of 25 MPa, and reactor outlet temperature of 550°C. Passive safety features similar to those of the simplified boiling water reactor are incorporated. Owing to the low density of supercritical water, additional moderator is added to thermalize the core in the thermal option. Note that the balance-of-plant is considerably simplified because the coolant does not change phase in the reactor. The SCWR system is highly ranked in economics because of the high thermal efficiency and plant simplification. If the fast-spectrum option can be developed, the SCWR system will also be highly ranked in sustainability. The SCWR is rated good in safety, and in proliferation resistance and physical protection. The SCWR system is primarily envisioned for missions in electricity production, with an option for actinide management. Given its R&D needs in materials compatibility, the SCWR system is estimated to be deployable by 2025.

16. EURATOM FP-6 PROJECTSGeneration-IV Innovative ConceptsVHTR – Very-High-Temperature Reactor System The Very-High-Temperature Reactor (VHTR) system uses a thermal neutron spectrum and a once-through uranium cycle. The VHTR system is primarily aimed at relatively faster deployment of a system for high temperature process heat applications, such as coal gasification and thermochemical hydrogen production, with superior efficiency. The reference reactor concept has a 600-MWth helium cooled core based on either the prismatic block fuel of the Gas Turbine–Modular Helium Reactor (GT-MHR) or the pebble fuel of the Pebble Bed Modular Reactor (PBMR). The primary circuit is connected to a steam reformer/steam generator to deliver process heat. The VHTR system has coolant outlet temperatures above 1000°C. It is intended to be a high-efficiency system that can supply process heat to a broad spectrum of high temperature and energy-intensive, nonelectric processes. The system may incorporate electricity generation equipment to meet cogeneration needs. The system also has the flexibility to adopt U/Pu fuel cycles and offer enhanced waste minimization. The VHTR requires significant advances in fuel performance and high temperature materials, but could benefit from many of the developments proposed for earlier prismatic or pebble bed gas-cooled reactors. Additional technology R&D for the VHTR includes high-temperature alloys, fiber-reinforced ceramics or composite materials, and zirconium-carbide fuel coatings. The VHTR system is highly ranked in economics because of its high hydrogen production efficiency, and in safety and reliability because of the inherent safety features of the fuel and reactor. It is rated good in proliferation resistance and physical protection, and neutral in sustainability because of its open fuel cycle. It is primarily envisioned for missions in hydrogen production and other process-heat applications, although it could produce electricity as well. The VHTR system is the nearest-term hydrogen production system, estimated to be deployable by 2020.

17. EURATOM FP-6 PROJECTSGeneration-IV Innovative ConceptsMSR- Molten Salt Reactor Sytem The Molten Salt Reactor (MSR) system produces fission power in a circulating molten salt fuel mixture with an epithermal-spectrum reactor and a full actinide recycle fuel cycle. In the MSR system, the fuel is a circulating liquid mixture of sodium, zirconium, and uranium fluorides. The molten salt fuel flows through graphite core channels, producing an epithermal spectrum. The heat generated in the molten salt is transferred to a secondary coolant system through an intermediate heat exchanger, and then through a tertiary heat exchanger to the power conversion system. The reference plant has a power level of 1,000 MWe. The system has a coolant outlet temperature of 700 degrees Celsius, possibly ranging up to 800 degrees Celsius, affording improved thermal efficiency. The closed fuel cycle can be tailored to the efficient burn up of plutonium and minor actinides. The MSR's liquid fuel allows addition of actinides such as plutonium and avoids the need for fuel fabrication. Actinides - and most fission products - form fluorinides in the liquid coolant. Molten fluoride salts have excellent heat transfer characteristics and a very low vapor pressure, which reduce stresses on the vessel and piping. The MSR system is top-ranked in sustainability because of its closed fuel cycle and excellent performance in waste burndown. It is rated good in safety, and in proliferation resistance and physical protection, and it is rated neutral in economics because of its large number of subsystems. It is primarily envisioned for missions in electricity production and waste burndown. Given its R&D needs for system development, the MSR is estimated to be deployable by 2025.

18. EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSCOVERS – VVER Safety Research Information, Database and Knowledge Management Links 25 PARTICIPANTS HU: AEKI, VEIKI CZ: NRI, CTU, NSTC SK: VUJE, STU, CENS FI: FORTUM, VTT, LUT EU: JRC IE DE: GRS, FZR NL: NRG BG: INRNE, TUS, ENIN, REL RU: RRCKI, OKBGP, EREC UA: NPPOSI, SSTCNRS, ISTC

19. Assessing topics contributing to enhancement of VVER operational safety and reliability Assessing “good practices” for the areas of nuclear safety and plant life management Creating common database of VVER relevant data, as well as the corresponding dissemination platforms Identifying and initiating requisite R&D tasks –analytical and experimental Strengthening communication with OECD and IAEA programs, especially those of experimental research Making use of information acquired within participation in other EURATOM FP6 projects, integrating it for VVER purposes (SARNET, NURESIM, NEPTUNO, PERFECT) Strengthening links between parties involved in VVER safety research and creating conditions for efficient exchange of information and cooperation even after the project is completed EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSCOVERS – VVER Safety Research - cont’d Project Objectives:

20. EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSCOVERS – VVER Safety Research - cont’d • WP3: Operational Safety • Five task groups: • Group A, Basic VVER safety items; Task: Discussion, identification and recommendations of the safety research needs • Group B, Experimental facilities and code validationTask: Information exchange in computer code validation • Group C, Severe accident assessment and management Task: Inventarisation of SAM-approaches and formulation of recommended approaches for VVER • Group D, Safety of refuelling pools • Task: Collection of activities in the field of spent fuel storage pool safety. • Group E, Steering activities in operational safety • In task group B a draft report was prepared "Identification of the VVER experimental facilities and description of the available and missing experimental capabilities"

21. WP3: Material and equipment ageing 4 subgroups: RPV, Steam generator, Piping and other passive primary components, Fatigue Dosimetry Upgrading and extending the VERLIFE code (PTS, P-T diagram, surveillance, MasterCurve etc.) and discussion of VERLIFE experience and upgrade; Collecting and exchanging new information on VVER Life Management practices (national solutions and practices); Collecting new information on VVER material ageing and life performance (e.g. Irradiation effect on cladding, application of Master Curve, annealing, steam generator corrosion, etc.); Determining fields where new common research is required; Define further necessary (common) R&D, and prepare common proposals. EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSCOVERS – VVER Safety Research - cont’d • WP5: Training and good practices exchange • 2005: Kick-off meetings • 2006: Training meetings • preparation of the reports, presentations for the End Users/Advisory Group, • dissemination of knowledge for the invited participants (students, docs, young specialists in nuclear) for all WPs.

22. EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSCOVERS – VVER Safety Research - cont’d • WP2: Information, database and knowledge management • Web portal (GRS) • Document management; • Rights management; • Collaboration (shared and meeting workspaces, discussions, events, announcements); • Search and retrieval; • Personalization • User training􀁺 • User support and usage guidelines􀁺 • Continuous introduction of content (Documents, information, links)􀁺 • Extension of functionality according to specific requirements of the teams

23. EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSNURESIM – European Platform for Nuclear Reactor Simulation NURESIM SCOPE AND OBJECTIVES Feb. 2005 – Jan. 2008 18 Organizations 13 Countries

24. EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSNURESIM – European Platform for Nuclear Reactor Simulation– cont’d NURESIM PLATFORM

25. EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSNURESIM – European Platform for Nuclear Reactor Simulation– cont’d Structure & Tasks • SP1: CORE PHYSICS • WP1.1 Advanced Monte Carlo Methods • TRIPOLI4 (CEA) + Adjoin methods (TUD+KTH) • WP1.2 Advanced Deterministic Diffusion and • Transport Methods • APOLLO2 + CRONOS => DESCARTES (CEA) • ANDES nodal solver + COBAYA3 cell-nodal (UPM) • WP1.3 Advanced Neutron Kinetics Methods • DESCARTES + COBAYA3 + DYN3D (FZR) • WP1.4 Coupled Calculations and Transient Benchmarks (MSLB, CRE for PWR,VVER)

26. EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSNURESIM – European Platform for Nuclear Reactor Simulation– cont’d Structure & Tasks – cont’d SP2: THERMALHYDRAULICS (with CFD) WP 2.1: Pressurized Thermal Shock & Direct Contact Condensation WP 2.2: Critical Heat Flux SCIENTIFIC CHALLENGES ASSOCIATED TO PTSandCHF • Condensation on the jet • Bubble Entrainment by jet • Turbulence production below jet • Turbulence production at free surface • Turbulence effects on condensation • Friction at free surface • Review of existing data • Identification of experimental needs • Implementation of available modules • Development of new physical models • Benchmarking and assessment • Interactions between • waves, turbulence & condensation • Effects of T° stratification • Flow Separation • Wall to fluid in CL & downcomer

27. EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSNURESIM – European Platform for Nuclear Reactor Simulation– cont’d Structure & Tasks – cont’d A multi-scale analysis of accidental transients with 3D simulation • SP3: MULTIPHYSICS • Review and specification, within the NURESIM platform, of coupling schemes for core analysis based on existing CP and TH core codes • At the nodal level (fuel assembly) • At the sub-node level (pin) • Development and integration within the NURESIM platform of core parameters interpolation and averaging schemes and data transfer • Application to PWR (MSLB) and BWR

28. EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSNURESIM – European Platform for Nuclear Reactor Simulation– cont’d Structure & Tasks – cont’d • SP4: SENSITIVITY AND UNCERTAINTY • Sensitivity and uncertainty analysis of multiphysics modules • - State of the Art report on deterministic and statistical methods • - Evaluation of critical points of model responses • Implementation within the NURESIM platform of procedures for propagation of uncertainties • SP5: INTEGRATION • Specific training courses on the SALOME platform • • Assistance in integrating codes • • Adaptation of the SALOME platform • • Ensuring consistency and non-regression

29. EURATOM FP-6 PROJECTSSAFETY OF EXISTING INSTALLATIONSNURESIM – European Platform for Nuclear Reactor Simulation– cont’d • NURESIM PROVIDES THE BASIS FOR A LONG TERM STRATEGY TOWARDS A EUROPEAN SOFTWARE PLATFORM FOR NUCLEAR ENERGY • • STRONG POSSIBLE BREAKTHROUGHS IN PHYSICAL MODELLING, NUMERICAL METHODS AND COMPUTER SCIENCE • UNIFY EFFORTS IN NUMERICAL SIMULATION IN REACTOR APPLICATIONS INSTEAD OF DISPERSED ONES NOW. • • AN ANSWER TO MEET THE NEEDS OF THE EUROPEAN NUCLEAR INDUSTRY, TO MAINTAIN ITS EFFICIENCY AND COMPETITIVENESS

30. SOME USEFUL WEB LINKS • http:// www. cordis.europa.eu/fp6 • http:// www.nuresim.org • http:// www.eu-neris.net • http://iriaxp.iri.tudelft.nl • http://gif.inel.gov • http:// www.gcfr.org Thank you for your attention