Localization of Accidents in Reactors of a Nuclear District Heating Plant

Abstract

There are considered principal decisions on the localization of accidents in the AST-500 nuclear district heating plant reactors based on the preferrable use of passive safety principles in the plant design and developed in-depth protection. There are shown positive sides of the use of a secondary vessel around the reactor for ensuring the NDHP safety in the LOCAs. The results are given of the analysis of main emergency situations with primary circuit loss-of-integrity including beyond design accidents with superposition of a large number of failures above the requirements of standards. It is shown that in low credible severe accidents the core cooling is ensured during the prolonged time and the non-permissible fuel elements overheating is excluded without recourse to emergency injection the radiological consequences of the accidents are close to the natural radiation background.