Reactor Core and Plant Design Concepts of the Canadian Supercritical Water-Cooled Reactor

Abstract

Canada has been developing a channel-type supercritical water-cooled nuclear reactor concept, often called the Canadian SCWR. This reactor concept targets to meet the goals of the Generation IV International Forum (GIF) for next generation nuclear reactor development, which include enhanced safety features (inherent safe operation and deploying passive safety features), improved resource utilization, sustainable fuel cycle, and greater proliferation resistance than Generation III nuclear reactors. The Canadian SCWR core consists of a high-pressure inlet plenum, a separate low-pressure heavy water moderator contained in calandria vessel, and more than 300 pressure tubes surrounded by the moderator. The reactor uses supercritical water as a coolant, and a direct steam power cycle to generate electricity. The reactor concept incorporates advanced safety features, such as passive core cooling, long-term decay heat rejection to environment and fuel melt prevention via passive moderator cooling. These features significantly reduce core damage frequency beyond existing nuclear reactors. This paper presents a description of the Canadian SCWR core design concept, its safety concepts, systems to supporting passive safety features, and the concept for the mechanical plant design. Integration of the reactor core with the supporting safety systems is also described to address long term reactor heat removal at various accident scenarios and station blackout conditions.