Vented low pressure containment strategy for the Modular High Temperature Gas-Cooled Reactor (MHTGR)

摘要

This paper presents the response of the 450 MW(t) MHTGR with a steam turbine power conversion system to expected and hypothetical accident source term assumptions. A range of vented low pressure containment (VLPC) strategies was considered that would enhance the retention of radionuclides. This study was prepared to review the technical merits of VLPC options in response to an NRC request during preapplication review of the steam cycle MMGR. The study found that, even under arbitrary hypothetical assumptions regarding significantly lower than expected fuel performance, vented low pressure containment options can effectively reduce accident doses. The reference design with a VLPC meets the 10CFR100 and prompt fatality doses even with lower than expected fuel performance. Alternative VLPC designs were studied which could be used to augment the current design to provide additional margin.