Patent ID: 6718001
Filing Date: 2004-04-06
Classification: G21C,Y02E

Abstract:
A nuclear reactor, comprising a nuclear fuel reactor core inside a pressure vessel; the pressure vessel having a shroud surrounding said reactor core and a downcomer of an outer region of said shroud; and a containment vessel surrounding said pressure vessel and having a pressure suppression pool, said nuclear reactor being one of a light water reactor and a heavy water reactor, whereinsaid pressure vessel contains the reactor core and a first heat exchanger for generating secondary steam, an inside of said containment vessel except a region installing said pressure vessel being vertically partitioned into three compartments, the pressure suppression pool having cooling water being formed in the upper compartment, a drywell for placing a feed water pipe of secondary cooling water, a main steam pipe of secondary steam being formed in the middle compartment, a wetwell of pressure suppression space being formed in the lower compartment, said drywell communicating with said pressure suppression pool through a plurality of vent pipes, an upper space of said pressure suppression pool communicating with said wetwell through a plurality of communicating pipes, a heat pipe containment vessel cooling system having a condensing heat exchanger arranged in a space above said pressure suppression pool and a first heat dissipater arranged outside said containment vessel in a position at a level higher than a level of said condensing heat exchanger, an interior of said condensing heat exchanger being filled with a heat medium, a gravitational water injection system being constructed as a plurality of gravitationally flow-down water injection pipes having an isolation valve between said pressure suppression pool and said pressure vessel, a pressure vessel bottom water flooding system being constructed as a plurality of pressure vessel bottom water flooding pipes between said pressure suppression pool and a lower portion of said drywell, an upper end of said gravitationally flow-down water injection pipe being arranged at a level higher than an upper end of said bottom, an upper end of said pressure vessel bottom water flooding pipe being arranged at a level higher than an upper end of said bottom, a lower portion of said pressure vessel bottom water flooding pipe being branched to a plurality of systems, at least one of said plurality of systems being connected to a fuse valve arranged in contact with an outer surface of a bottom portion of said pressure vessel, at least one other of said plurality of systems being opened to a lower space of said drywell through an isolation valve, a reactor core isolation cooling system being constructed as a cooling vessel and a second heat dissipater, said cooling vessel being filled with a coolant and containing a second heat exchanger in said coolant, said cooling vessel being arranged at a level higher than said reactor core inside said containment vessel, said second heat exchanger being connected to said pressure vessel using an inflow pipe and a water injection pipe, a lower end of said inflow pipe and a lower end of said water injection pipe being opened to said pressure vessel at a level lower than a water surface level in said pressure vessel during operation of said nuclear reactor, said second heat dissipater being arranged outside said containment vessel at a level higher than said cooling vessel, an upper end of said cooling vessel communicating with a cooler through a gas inflow pipe, said cooler communicating with said cooling vessel through a liquid returning pipe.