Shutdown system for a nuclear steam supply system

A nuclear steam supply system with shutdown cooling system, the nuclear steam supply system comprising:

• a reactor vessel having an internal cavity;
• a reactor core comprising nuclear fuel disposed within the internal cavity and operable to heat a primary coolant;
• a steam generating vessel fluidly coupled to the reactor vessel and containing a secondary coolant for producing steam to operate a steam turbine, the steam generating vessel including a superheater section and a steam generator section;
• a riser pipe positioned inside the steam generating vessel and fluidly coupled to the reactor vessel;
• a primary coolant flow loop formed within the reactor vessel and the steam generating vessel, the primary coolant flow loop being configured and operable for circulating primary coolant through the reactor vessel and steam generating vessel;
• a primary coolant cooling system comprising:
• a first pump having an inlet fluidly coupled to the primary coolant flow loop, the first pump configured and operable to extract and pressurize a portion of the primary coolant from the primary coolant loop;
• a Venturi injection nozzle having an inlet fluidly coupled to a discharge of the first pump and positioned inside the riser pipe in the steam generating vessel, the injection nozzle receiving and injecting the pressurized portion of the primary coolant into the riser pipe from the pump;
• and
• a first heat exchanger configured and operable to cool the extracted primary coolant prior to injecting the pressurized portion of the primary coolant;
• a secondary coolant cooling system comprising:
• a steam bypass condenser having an inlet fluidly coupled to the superheater section of the steam generator vessel for receiving and cooling secondary coolant in a steam phase;
• a second heat exchanger having an inlet fluidly coupled to the steam generator section of the steam generating vessel for receiving and cooling secondary coolant in a liquid phase;
• a second pump having an inlet fluidly coupled to the steam bypass condenser and the second heat exchanger, the second pump configured and operable to pressurize and circulate secondary coolant through the steam generator in a secondary coolant flow loop;
• wherein the secondary coolant cooling system is configured to cool secondary coolant in either the steam or liquid phase.

A nuclear steam supply system with shutdown cooling system, the nuclear steam supply system comprising:

• a reactor vessel having an internal cavity;
• a vertically elongated reactor core comprising nuclear fuel disposed within the internal cavity and operable to heat a primary coolant;
• a vertically elongated steam generating vessel fluidly coupled to the reactor vessel and containing a secondary coolant for producing steam to operate a steam turbine, the steam generating vessel including a superheater section and a steam generator section;
• a vertically elongated riser pipe positioned inside the steam generating vessel and fluidly coupled to the reactor vessel;
• a primary coolant flow loop formed within the reactor vessel and the steam generating vessel, the primary coolant flow loop being configured and operable for circulating primary coolant through the reactor vessel and steam generating vessel;
• a secondary coolant flow loop formed outside of the reactor vessel and steam generating vessel, the secondary coolant flow loop being configured and operable for circulating secondary coolant through the steam generating vessel;
• and
• a Venturi jet pump disposed inside the riser pipe of the steam generating vessel, the jet pump including an injection nozzle fluidly coupled to the primary coolant flow loop,
• wherein the jet pump receives and injects a portion of the primary coolant into the riser pipe which draws and mixes primary coolant from the reactor vessel with the injected portion of the primary coolant in the riser pump to circulate primary coolant through the primary coolant flow loop.