Zirconium Ceramics for Nuclear Reactor
Design of Zircon-based Ceramics for a Nuclear Reactor Core Melt Catcher
Tech Area / Field
- FIR-ENG/Reactor Engineering and NPP/Fission Reactors
8 Project completed
Senior Project Manager
Tocheny L V
IVTAN (High Temperatures), Russia, Moscow
- State University of Nizhny Novgorod / Research Intitute of Mechanics, Russia, N. Novgorod reg., N. Novgorod\nOKB Gidropress, Russia, Moscow reg., Podolsk\nKurchatov Research Center, Russia, Moscow\nVNIIEF, Russia, N. Novgorod reg., Sarov\nMendeleev Chemical Technological University, Russia, Moscow
- CEA / DRN / DER / CEN Cadarache, France, Cadarache\nForschungszentrum Karlsruhe Technik und Umwelt, Germany, Karlsruhe\nEuropean Commission / Joint Research Center / Institute for Systems, Informatics and Safety, Italy, Ispra\nTampere University of Technology / Institute of Materials Science, Finland, Tampere
Project summaryIn case of severe accident of nuclear reactor, when the reactor core is being melt, it is important to prevent spreading of formed corium (debris) to environment. By estimation, the molten corium temperature can reach 2800-3000K.
Recent investigations carried out in several countries (Germany, USA, Japan and Russia) have showen that existing protection system based on a concrete shaft can hold molten corium only for few days.
Over many years, HEDRC SA "IVTAN" RAS has been working in the field of scientific problems of MHD power generation. In this work zirconia-based high-refractory ceramics for working temperatures above 2300K has been developed. We intend to use this experience as a basis for developing ceramics for corium catcher.
In 1994, preliminary experiments on interaction of zirconia ceramics with a pure zirconium and an alloy, which contains 80% of steel and 20% of Zr, were carried out. These tests confirmed perspectivness of the ceramics proposed. No erosion of ceramics was observed. This proved a perspective of the ceramics as a material for catcher.
It is supposed that a material of the catcher will be exposed to the action of several factors: mechanical shock caused by a fall of a great molten mass and construction elements into the catcher and vapor explosion due to water-zirconium contact.
Moreover, thermal shock occurs when molten corium with temperature of 2800K gets on the catcher surface; radiative impact will take place, as well.
Therefore, the main objectives of the project are as follows:
- development of the thermoshock-resistant zirconia-based ceramics/
- investigation of the kinetics of interaction of the ceramics with the main corium components under various gas atmosphere at ultimately high temperatures (>2300K),including task to creation some mineral like matrix on the basis of ZrO for solution of problem to bury of corium;
- investigations of thermomechanical and thermophysical properties of the ceramics;
- designing several versions of the catcher model construction;
- developing a set of sizes of the ceramics articles for catcher lining;
- working out the essentials of the technology of fabrication of the ceramics articles of a complex shape;
- elaborating the temporary technical specifications on ceramic article properties that should be assured;
- creating the catcher model.