Concrete Protection of Reactors
Design of a nuclear reactor core melt catcher on the basis of zirconia concrete.
Tech Area / Field
- FIR-MAT/Materials and Materials Conversion/Fission Reactors
8 Project completed
Senior Project Manager
Tocheny L V
IVTAN (High Temperatures), Russia, Moscow
- OGBET, Russia, Moscow\nInstitute of Safe Atomic Power Engineering Development, Russia, Moscow\nOKB Gidropress, Russia, Moscow reg., Podolsk\nResearch Institute of Technology, Russia, Leningrad reg., Sosnovy Bor
- Forschungszentrum Karlsruhe Technik und Umwelt / Institut für Neutronenphysik und Reaktortechnik, Germany, Karlsruhe\nEuropean Commission / Joint Research Center / Institute for Systems, Informatics and Safety, Italy, Ispra\nSiemens AG, Germany, Erlangen
Project summaryAt the last time it was showed that nuclear reactor body and using (now) concrete protection can hold back a core melt only a few days.
Available literary information allows to suppose that using of high-temperature zirconium concrete (T /melt. ZrO2/ = 2700 °C) can increase this time at least by 100 times or even to ensure constant containment. Thus the main problem of atomic stations safety - expulsion of a melt exit into environment - can be solve.
Laboratory of high-temperature oxides materials HEDRC in result of participation in MGD-project during 80-90 years begins investigations and tests of zirconium materials. It was selected as the most technological and stable to thermal chock concrete variant. This concrete successfully used as crown back-up lining at 2200 °C during more than 200 hours.
Cement is the second component of concrete. At temperature more than 1700 °C can apply only monoaluminate of barium (SA, T /melt./ = 2000 °C) and monoaluminate of strontium (SA, 1900 °C). These water-hardening cements have studied insufficiently. Labo-ratory carries out such investigations third years. The main atten-tion is spared investigations of mixing and hardening conditions these cements in concrete composition. In 1990 was carried out the verification of resistance this concrete to influence of Fe+Zr+Ni+Cr melt (model of core melt) at 1700 °C.
Experiments indicate that interaction of melt with this concrete less than with high-aluminum concrete (Al2O3 and calcium aluminate) by 10 times and less than with ordinary concrete (Al2O3+SiO2 with calcium cilicates) by 100 times.
It is important that zirconium concrete contains small quantity of water (3% mass.), this fact results in only a few extraction hydrogen at interaction melt with concrete (decrease of secondary explosion spring).
It is supposed:
- to continue and complete investigations of bending properties of BA and SA;
- to create optimum composition of zirconium concrete;
- to create optimum technology of preparation and hardening concrete;
- to investigate interaction concrete with melts Zr, Fe and models of core melt;
- to investigate influence of melt temperature and character atmosphere;
- to carry out demonstration stand tests;
- to work out construction and technological basis of core melt concrete catcher;
- to investigate durable resistance concrete in water and to estimate possibility of using in nuclear reactor body protective concrete layer placed on its bottom;
- to investigate high-temperature (> 2000 °C) concrete characte-ristics first of all heat conduction and mechanical properties including creep;
- to work out of catcher construction on a base of zirconium concrete and recommendations its mounting into nuclear reactor;
- to create mathematical model of core melt interaction with zirconium concrete.