A DETERMINISTIC MODEL FOR CORROSION AND ACTIVITY INCORPORATION IN NUCLEAR POWER PLANTS ANTIOXI

1. A DETERMINISTIC MODEL FOR CORROSION AND ACTIVITYINCORPORATION IN NUCLEAR POWER PLANTSANTIOXI Advisory Board meeting 6.2.2007

2. Project consortium • VTT Technical Research Centre of Finland • >20 years of experience in electrochemical materials studies • >10 years of experience in oxide film modelling • ALARA Engineering • >10 years of experience in NPP chemistries • Several own tools for radiolysis chemistry and ECP analysis and simulation • BG H2 Society • established in 2003 • a volunteer, independent, non-governmental formation, registered under the Law on the Non-profit Corporate Bodies • BHS is a key partner of the Ministry of Defense, Ministry of Environment and Waters, Ministry of Energetics, Ministry of Science and Education, Bulgarian Academy of Science and University of Chemical Technology and Metallurgy. • Since 2004, BHS is a partner of the European Hydrogen Association (EHA).

3. Introduction of the project (1/3) The problem: • Why do different radioactive particles attach to different material surfaces as they do? • What are the mechanisms? • How does the activity affect corrosion phenomena and material integrity? • How transients during fuel cycle affect the incorporation rate? • Can the activity levels at the surfaces be estimated "on-line"? …and its importance: • Better estimations of activity levels lead (possibly) to lower contamination of maintenance personnel. • Helps in planning decontamination campaigns and in estimating recontamination rates. • New plants are under construction (Finland), will be constructed (Bulgaria) and old ones will be shut down (Bulgaria, Sweden). In all of these cases the activity plays an important role in determining material and chemistry options as well as the preventive actions for accidents.

4. Introduction of the project (2/3) The key scientific objectives of the proposed project can be summarized as follows: • Development of a new generation of the model for oxide films integrated with the existing radiolysis/activity incorporation model in order to produce a model approach that is • more deterministic, • has an increased predictive ability and • is smarter and/or more adaptive, i.e. able to take into account the effect of a variety of environments on the oxide films in a fully quantitative way. • To further refine the model for the inner, compact part of the oxide film on material surfaces • kinetic and transport parameters pertinent to different metallic constituents of the layer will be determined on the basis of available values obtained from electrochemical data and newly developed procedures for quantitative evaluation of these parameters from in-depth compositional profiles of the oxide film • the energetic heterogeneity of the transport medium will be taken into account by using distribution functions for the diffusion coefficients of individual species in the compact film and evaluating the role of grain boundaries in the transfer of matter and charge through such layers • To implement in the model the interaction between material surfaces and the active ionic species dissolved in the NPP primary coolant • a series of high temperature experiments will be used to obtain thermodynamic and kinetic data on the adsorption / surface complexation and re-precipitation reactions of different cations at different iron and mixed iron-nickel oxides

5. Introduction of the project (3/3) The preliminary work for understanding activity incorporation was made between 2004 - 2006 • SAFIR The Finnish Research Programme on Nuclear Power Plant Safety 2003 - 2006 • PROJECT: LWR oxide model for improved understanding of activity build-up and corrosion phenomena (LWROXI) • Main results: state-of the-art description of the material modelling, preliminary power plant data analysis and development of laboratory techniques to study surface phenomena

6. Work packages

7. Advisory Board tasks (1/2) • The Advisory Board is an impartial body to provide strategic oversight on the project. • The Advisory Board consists of four or five members being appointed on a personal basis taking account of their personnel expertise. The main selection criterion for the Advisory Board members is the high knowledge level in the field of study of ANTIOXI. They must act impartially at all times and independently from the particular goals or needs of their respective employers; any conflict of interest in this respect should be identified as and when it arises. • Its main function is to advise the participants on the strategic direction and operational management of the project, in particular to assist the project in achieving its declared objectives in a timely and effective way. • The Advisory Board, in general, meets once or twice a year. • The Advisory Board will meet first time in four months from the start of the project. • Otherwise, the communication between coordinator and advisory board will be run via email. • If the recommendations/decision in the Advisory Board not unanimous, voting is used to complete the decision-making process. • The Project Coordinator attends all meetings, but without vote. • The Project Coordinator provides the main link between the project and the Advisory Board. Other partners of the project may participate at the meetings of the Advisory Board, but without vote.

8. Advisory board members • Dr. Marc Vankeerberghen (SCK-CEN) • Dr. Kari Mäkelä (Fortum Power and Heat, Loviisa NPP) • Dr. Sami Palonen (Teollisuuden Voima, TVO, Olkiluoto NPP) • Dr. Rolf Riess (NP-Consulting)

9. Advisory Board tasks (2/2) The main tasks and duties of the Advisory Board are: • to review contractually required reports; • to advise on all aspects of the project, in particular: • priorities and need for modification of the work programme or elements of it, • project management including quality assurance and control, • progress of work, • emerging issues and needs. • to comment as well as suggest modifications to the planned research or time schedules. • All reports and other publications will be delivered to the AB members for check-up 2-3 weeks before deadline "The Commission services should be informed, one month in advance, of any publications or initiatives (eg, articles in Journals, press releases, conference papers, etc) by the Consortium which may have social, economic and/or political impact or could trigger significant media interest."

10. Dissemination of knowledge (1/3) • All research reports published as VTT research reports • Dissemination in • Finland mainly via the SAFIR2010 research programme • Sweden via seminars directed to representatives of NPPs and authorities • Bulgaria via seminars directed to representatives of NPPs and authorities, via courses in the University of Metallurgy and Chemical Technology • Internet site: http://www.vtt.fi/proj/antioxi/ • Includes the project presentation, where else it needs to be published? • Communication action plan within 6 months of contract start • Dissemination between EU PERFECT -project ??

11. Dissemination of knowledge (2/3) Planned conferences/meetings/seminars:

12. Dissemination of knowledge (3/3) Planned publications:

13. Performance indicators