NUCLEAR STEAM SUPPLY AND START-UP SYSTEM, PASSIVELY-COOLED SPENT NUCLEAR FUEL POOL SYSTEM AND METHOD THEREFOR, COMPONENT COOLING WATER SYSTEM FOR NUCLEAR POWER PLANT, PASSIVE REACTOR COOLING SYSTEM, STEAM GENERATOR FOR NUCLEAR STEAM SUPPLY SYSTEM
A nuclear steam supply system having a start-up sub-system for heating a primary coolant. The nuclear steam supply system comprises a reactor vessel with core comprising nuclear fuel, and steam generating vessel fluidly coupled to the reactor vessel. A primary coolant loop formed within the reactor vessel and the steam generating vessel circulates primary coolant through the loop. A steam supply start-up sub-system is fluidly coupled to the primary coolant loop. The start-up sub-system is configured and operable to: (1) extract and receive a portion of the primary coolant from the primary coolant loop; (2) heat the portion of the primary coolant to form a heated portion of the primary coolant; and (3) inject the heated portion of the primary coolant back into the primary coolant loop.
NUCLEAR FUEL CORE AND METHODS OF FUELING AND/OR DEFUELING A NUCLEAR REACTOR, CONTROL ROD DRIVE SYSTEM FOR NUCLEAR REACTOR, SHUTDOWN SYSTEM FOR NUCLEAR STEAM SUPPLY SYSTEM, NUCLEAR REACTOR SHROUD, AND/OR LOSS-OF-COOLANT ACCIDENT REACTOR COOLING SYSTEM
Portable nuclear fuel cartridge comprising a unitary support structure and plurality of nuclear fuel assemblies that collectively form a nuclear fuel core. Control rod drive system for a nuclear reactor. A nuclear steam supply system having a shutdown system for removing residual decay heat generated by a nuclear fuel core. A nuclear reactor including a cylindrical body having an internal cavity, nuclear fuel core, and a shroud disposed in the cavity. A nuclear reactor cooling system with passive cooling capabilities operable during a loss-of-coolant accident (LOCA) without available electric power.
G21C 13/02 - Pressure vesselsContainment vesselsContainment in general Details
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
A control rod drive system (CRDS) for use in a nuclear reactor. In one embodiment, the system generally includes a drive rod mechanically coupled to a control rod drive mechanism (CRDM) operable to linearly raise and lower the drive rod along a vertical axis, a rod cluster control assembly (RCCA) comprising a plurality of control rods insertable into a nuclear fuel core, and a drive rod extension (DRE) releasably coupled at opposing ends to the drive rod and RCCA. The CRDM includes an electromagnet which operates to couple the CRDM to DRE. In the event of a power loss or SCRAM, the CRDM may be configured to remotely uncouple the RCCA from the DRE without releasing or dropping the drive rod which remains engaged with the CRDM and in position.
G21C 13/02 - Pressure vesselsContainment vesselsContainment in general Details
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
A method for heating primary coolant in a nuclear reactor system during system start-up. A primary coolant loop fluidly couples together a reactor vessel and a steam generating vessel. The primary coolant loop is filled with primary coolant. A portion of the primary coolant is taken from the primary coolant loop and placed into a start-up sub-system. The portion is heated while in the sub-system to form a heated portion of the primary coolant. The heated portion is returned into the primary coolant loop. The method allows for the primary coolant to be heated to a no-load operating temperature.
A nuclear reactor support system that, in one embodiment, includes a reactor vessel, a reactor core disposed within the reactor vessel, an upper portion of the reactor vessel located above a ground plane and a lower portion of the reactor vessel located below the ground plane. The support system further includes a first flange fixedly attached to the upper portion of the reactor vessel and contacting the ground plane, the first flange supporting the reactor vessel, a second flange fixedly attached to the upper portion of the reactor vessel above the ground plane, the second flange spaced vertically apart from the first flange, and a plurality of welded lugs extending vertically between the first and second flanges. The first flange supports the entire weight of the reactor vessel in a cantilevered manner.
G21C 13/024 - Supporting constructions for pressure vessels or containment vessels
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
G21C 1/08 - Heterogeneous reactors, i.e. in which fuel and moderator are separated moderator being highly pressurised, e.g. boiling-water reactor, integral-superheat reactor, pressurised-water reactor
G21C 7/32 - Control of nuclear reaction by varying flow of coolant through the core
G21C 15/26 - Promoting flow of the coolant by convection, e.g. using chimneys, using divergent channels
G21C 13/04 - Arrangements for expansion and contraction
A control rod drive system (CRDS) for use in a nuclear reactor. In one embodiment, the system generally includes a drive rod mechanically coupled to a control rod drive mechanism (CRDM) operable to linearly raise and lower the drive rod along a vertical axis, a rod cluster control assembly (RCCA) comprising a plurality of control rods insertable into a nuclear fuel core, and a drive rod extension (DRE) releasably coupled at opposing ends to the drive rod and RCCA. The CRDM includes an electromagnet which operates to couple the CRDM to DRE. In the event of a power loss or SCRAM, the CRDM may be configured to remotely uncouple the RCCA from the DRE without releasing or dropping the drive rod which remains engaged with the CRDM and in position.
A nuclear reactor in one embodiment includes a cylindrical body having an internal cavity, a nuclear fuel core, and a shroud disposed in the cavity. The shroud comprises an inner shell, an outer shell, and a plurality of intermediate shells disposed between the inner and outer shells. Pluralities of annular cavities are formed between the inner and outer shells which are filled with primary coolant such as demineralized water. The coolant-filled annular cavities may be sealed at the top and bottom and provide an insulating effect to the shroud. In one embodiment, the shroud may comprise a plurality of vertically-stacked self-supported shroud segments which are coupled together.
A nuclear steam supply system utilizing gravity-driven natural circulation for primary coolant flow through a fluidly interconnected reactor vessel and a steam generating vessel. In one embodiment, the steam generating vessel includes a plurality of vertically stacked heat exchangers operable to convert a secondary coolant from a saturated liquid to superheated steam by utilizing heat gained by the primary coolant from a nuclear fuel core in the reactor vessel. The secondary coolant may be working fluid associated with a Rankine power cycle turbine-generator set in some embodiments. The steam generating vessel and reactor vessel may each be comprised of vertically elongated shells, which in one embodiment are arranged in lateral adjacent relationship. In one embodiment, the reactor vessel and steam generating vessel are physically discrete self-supporting structures which may be physically located in the same containment vessel.
G21C 15/14 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from ducts conducting a hot fluidArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from ducts comprising auxiliary apparatus, e.g. pumps, cameras
F22B 1/02 - Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
G21C 13/04 - Arrangements for expansion and contraction
G21C 15/22 - Structural association of coolant tubes with headers or other pipes, e.g. in pressure tube reactors
G21C 15/26 - Promoting flow of the coolant by convection, e.g. using chimneys, using divergent channels
A control rod drive system (CRDS) for use in a nuclear reactor. In one embodiment, the system generally includes a drive rod mechanically coupled to a control rod drive mechanism (CRDM) operable to linearly raise and lower the drive rod along a vertical axis, a rod cluster control assembly (RCCA) comprising a plurality of control rods insertable into a nuclear fuel core, and a drive rod extension (DRE) releasably coupled at opposing ends to the drive rod and RCCA. The CRDM includes an electromagnet which operates to couple the CRDM to DRE. In the event of a power loss or SCRAM, the CRDM may be configured to remotely uncouple the RCCA from the DRE without releasing or dropping the drive rod which remains engaged with the CRDM and in position.
A nuclear steam supply system utilizing gravity-driven natural circulation for primary coolant flow through a fluidly interconnected reactor vessel and a steam generating vessel. In one embodiment, the steam generating vessel includes a plurality of vertically stacked heat exchangers operable to convert a secondary coolant from a saturated liquid to superheated steam by utilizing heat gained by the primary coolant from a nuclear fuel core in the reactor vessel. The secondary coolant may be working fluid associated with a Rankine power cycle turbine-generator set in some embodiments. The steam generating vessel and reactor vessel may each be comprised of vertically elongated shells, which in one embodiment are arranged in lateral adjacent relationship. In one embodiment, the reactor vessel and steam generating vessel are physically discrete self-supporting structures which may be physically located in the same containment vessel.
G21C 15/14 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from ducts conducting a hot fluidArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from ducts comprising auxiliary apparatus, e.g. pumps, cameras
G21C 15/22 - Structural association of coolant tubes with headers or other pipes, e.g. in pressure tube reactors
G21C 13/04 - Arrangements for expansion and contraction
F22B 1/02 - Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
A method for heating primary coolant in a nuclear supply system in one embodiment includes filling a primary coolant loop within a reactor vessel and a steam generating vessel that are fluidly coupled together with a primary coolant, drawing a portion of the primary coolant from the primary coolant loop and into a start-up sub-system, heating the portion of the primary coolant to form a heated portion of the primary coolant, and injecting the heated portion of the primary coolant back into the primary coolant loop. The primary coolant may be heated to a no-load operating temperature.
G21C 1/08 - Heterogeneous reactors, i.e. in which fuel and moderator are separated moderator being highly pressurised, e.g. boiling-water reactor, integral-superheat reactor, pressurised-water reactor
12.
OPTIMIZED NUCLEAR FUEL CORE DESIGN FOR A SMALL MODULAR REACTOR
A fuel core for a nuclear reactor in one embodiment includes an upper internals unit and a lower internals unit comprising nuclear fuel assemblies. The assembled fuel core includes an upper core plate, a lower core plate, and a plurality of channel boxes extending therebetween. Each channel box comprises a plurality of outer walls and inner walls collectively defining a longitudinally-extending interior channels or cells having a transverse cross sectional area configured for holding no more than a single nuclear fuel assembly in some embodiments. A cylindrical reflector circumferentially surrounds channel boxes and is engaged at opposing ends by the upper and lower core plates. Adjacent cells within each channel box are formed on opposite sides of inner walls such that the cells are separated from each other by the inner walls alone without any water gaps therebetween which benefits neutronics for some small modular reactor designs.
A fuel core for a nuclear reactor in one embodiment includes an upper internals unit and a lower internals unit comprising nuclear fuel assemblies. The assembled fuel core includes an upper core plate, a lower core plate, and a plurality of channel boxes extending therebetween. Each channel box comprises a plurality of outer walls and inner walls collectively defining a longitudinally-extending interior channels or cells having a transverse cross sectional area configured for holding no more than a single nuclear fuel assembly in some embodiments. A cylindrical reflector circumferentially surrounds channel boxes and is engaged at opposing ends by the upper and lower core plates. Adjacent cells within each channel box are formed on opposite sides of inner walls such that the cells are separated from each other by the inner walls alone without any water gaps therebetween which benefits neutronics for some small modular reactor designs.
G21C 3/18 - Internal spacers or other non-active material within the casing, e.g. compensating for expansion of fuel rods or for compensating excess reactivity
G21C 15/10 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from reflector or thermal shield
G21C 11/06 - Reflecting shields, i.e. for minimising loss of neutrons
G21C 5/06 - Means for locating or supporting fuel elements
G21C 5/02 - Moderator or core structureSelection of materials for use as moderator Details
A nuclear reactor cooling system with passive cooling capabilities operable during a loss-of-coolant accident (LOCA) without available electric power. The system includes a reactor vessel with nuclear fuel core located in a reactor well. An in-containment water storage tank is fluidly coupled to the reactor well and holds an inventory of cooling water. During a LOCA event, the tank floods the reactor well with water. Eventually, the water heated by decay heat from the reactor vaporizes producing steam. The steam flows to an in-containment heat exchanger and condenses. The condensate is returned to the reactor well in a closed flow loop system in which flow may circulate solely via gravity from changes in phase and density of the water. In one embodiment, the heat exchanger may be an array of heat dissipater ducts mounted on the wall of the inner containment vessel surrounded by a heat sink.
G21C 13/02 - Pressure vesselsContainment vesselsContainment in general Details
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
An entire nuclear fuel core comprising a plurality of fuel assemblies is preassembled in a nuclear fuel cartridge having a self-supporting unitary support structure. During a refueling operation, the unitary support structure is moved into a nuclear reactor vessel. The unitary support structure may be formed by top and bottom core plates coupled together by vertically-oriented connecting rods which compress the fuel assemblies therebetween. A plurality of reflector wall segments circumscribe the core and are the coupled together between the core plates by the connecting rods which are coupled to the core plates. The connecting rods may extend through the wall segments.
G21C 19/18 - Apparatus for bringing fuel elements to the reactor charge area, e.g. from a storage place
G21C 3/33 - Supporting or hanging of elements in the bundleMeans forming part of the bundle for inserting it into, or removing it from, the coreMeans for coupling adjacent bundles
A nuclear steam supply system includes an elongated reactor vessel having an internal cavity with a central axis, a reactor core having nuclear fuel disposed within the internal cavity, and a steam generating vessel having at least one heat exchanger section, the steam generating vessel being fluidicly coupled to the reactor vessel. The reactor vessel includes a shell having an upper flange portion and a head having a head flange portion. The upper flange portion is coupled to the head flange portion, wherein the upper flange portion extends into the internal cavity, and the head flange portion extends outward from the internal cavity. The flanges have a space saving design which are configured to minimize outward extension from the cavity while still providing desired leak protection at the interface between the shell and the head.
A nuclear reactor in one embodiment includes a cylindrical body having an internal cavity, a nuclear fuel core, and a shroud disposed in the cavity. The shroud comprises an inner shell, an outer shell, and a plurality of intermediate shells disposed between the inner and outer shells. Pluralities of annular cavities are formed between the inner and outer shells which are filled with primary coolant such as demineralized water. The coolant-filled annular cavities may be sealed at the top and bottom and provide an insulating effect to the shroud. In one embodiment, the shroud may comprise a plurality of vertically-stacked self-supported shroud segments which are coupled together.
A component cooling water system for a nuclear power plant. In one embodiment, the system includes an inner containment vessel housing a nuclear reactor and an outer containment enclosure structure. An annular water reservoir is formed between the containment vessel and containment enclosure structure which provides a heat sink for dissipating thermal energy. A shell-less heat exchanger is provided having an exposed tube bundle immersed in water held within the annular water reservoir. Component cooling water from the plant flows through the tube bundle and is cooled by transferring heat to the annular water reservoir. In one non-limiting embodiment, the tube bundle may be U-shaped.
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
A nuclear reactor cooling system with passive cooling capabilities operable during a reactor shutdown event without available electric power. In one embodiment, the system includes a reactor vessel with nuclear fuel core and a steam generator fluidly coupled thereto. Primary coolant circulates in a flow loop between the reactor vessel and steam generator to heat secondary coolant in the steam generator producing steam. The steam flows to a heat exchanger containing an inventory of cooling water in which a submerged tube bundle is immersed. The steam is condensed in the heat exchanger and returned to the steam generator forming a closed flow loop in which the secondary coolant flow is driven by natural gravity via changes in density from the heating and cooling cycles. In other embodiments, the cooling system is configured to extract and cool the primary coolant directly using the submerged tube bundle heat exchanger.
G21C 13/02 - Pressure vesselsContainment vesselsContainment in general Details
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
A nuclear reactor system that, in one embodiment, utilizes natural circulation to circulate a primary coolant in a single-phase through a reactor core and a heat exchange sub-system. The heat exchange subsystem is located outside of the nuclear reactor pressure vessels and, in some embodiments, is designed so as to not cause any substantial pressure drop in the flow of the primary coolant within the heat exchange sub-system that is used to vaporize a secondary coolant. In another embodiment, a nuclear reactor system is disclosed in which the reactor core is located below ground and all penetrations into the reactor pressure vessel are located above ground.
G21C 15/26 - Promoting flow of the coolant by convection, e.g. using chimneys, using divergent channels
G21C 1/08 - Heterogeneous reactors, i.e. in which fuel and moderator are separated moderator being highly pressurised, e.g. boiling-water reactor, integral-superheat reactor, pressurised-water reactor
G21C 7/32 - Control of nuclear reaction by varying flow of coolant through the core
G21C 13/04 - Arrangements for expansion and contraction
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
A control rod drive system (CRDS) for use in a nuclear reactor. In one embodiment, the system generally includes a drive rod mechanically coupled to a control rod drive mechanism (CRDM) operable to linearly raise and lower the drive rod along a vertical axis, a rod cluster control assembly (RCCA) comprising a plurality of control rods insertable into a nuclear fuel core, and a drive rod extension (DRE) releasably coupled at opposing ends to the drive rod and RCCA. The CRDM includes an electromagnet which operates to couple the CRDM to DRE. In the event of a power loss or SCRAM, the CRDM may be configured to remotely uncouple the RCCA from the DRE without releasing or dropping the drive rod which remains engaged with the CRDM and in position.
A nuclear steam supply system having a shutdown system for removing residual decay heat generated by a nuclear fuel core. The steam supply system may utilize gravity-driven primary coolant circulation through hydraulic-ally interconnected reactor and steam generating vessels forming the steam supply system. The shutdown system may comprise primary and secondary coolant systems. The primary coolant cooling system may include a jet pump comprising an injection nozzle disposed inside the steam generating vessel A portion of the circulating primary coolant is extracted, pressurized and returned to the steam generating vessel to induce coolant circulation under reactor shutdown conditions. The extracted primary coolant may further be cooled before return to the steam generating vessel in some operating modes. The secondary coolant cooling system includes a pumped and cooled flow circuit operating to circulate and cool the secondary coolant, which in tun extracts heat from and cools the primary coolant.
F22B 1/02 - Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
G21C 1/32 - Integral reactors, i.e. reactors wherein parts functionally associated with the reactor but not essential to the reaction, e.g. heat exchangers, are disposed inside the enclosure with the core
G21C 15/00 - Cooling arrangements within the pressure vessel containing the coreSelection of specific coolants
A nuclear steam supply system utilizing gravity-driven natural circulation for primary coolant flow through a fluidly interconnected reactor vessel and a steam generating vessel. In one embodiment, the steam generating vessel includes a plurality of vertically stacked heat exchangers operable to convert a secondary coolant from a saturated liquid to superheated steam by utilizing heat gained by the primary coolant from a nuclear fuel core in the reactor vessel. The secondary coolant, may be working fluid associated with a Rankine power cycle turbine-generator set in some embodiments. The steam generating vessel and reactor vessel may each be comprised of vertically elongated shells, which in one embodiment are arranged in lateral adjacent relationship. In one embodiment, the reactor vessel and steam generating vessel are physically discrete self-supporting structures which may be physically located in the same containment vessel.
G21C 15/14 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from ducts conducting a hot fluidArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from ducts comprising auxiliary apparatus, e.g. pumps, cameras
G21C 13/04 - Arrangements for expansion and contraction
G21C 15/26 - Promoting flow of the coolant by convection, e.g. using chimneys, using divergent channels
A nuclear reactor in one embodiment includes a cylindrical, body having an internal cavity, a nuclear fuel core, and a shroud disposed in the cavity. The shroud comprises an inner shell, an outer shell and a plurality of intermediate shells disposed between the inner and outer shells. Pluralities of annular cavities are formed between the inner and outer shells which are filled with primary coolant such as demineralized water. The coolant-filled annular cavities may be sealed at the top and bottom and provide an insulating effect to the shroud. In one embodiment, the shroud may comprise a plurality of vertically-stacked self-supported shroud segments which are coupled together.
A passively-cooled spent nuclear fuel pool system in one embodiment includes a containment vessel comprising a thermally conductive shell and an annular reservoir surrounding the shell that holds a liquid coolant forming a heat sink. A spent fuel pool is disposed inside the containment vessel and includes a body of water in contact with a peripheral sidewall of the fuel pool. At least one spent nuclear fuel rod submerged in the body of water heats the water. The peripheral sidewall of the spent fuel pool is formed by a portion of the shell of the containment vessel adjacent to the fuel pool, thereby defining a shared common heat transfer wall. The heat transfer wall operates to transfer heat from the body of water in the spent fuel pool to the heat sink to cool the body of water. The heat transfer wall comprises metal in one embodiment.
A nuclear power generation system and related power cycle are disclosed, in one embodiment, the system includes primary coolant circulation through a hydraulically interconnected reactor containing nuclear fuel and a steam generating vessel collectively defining a steam supply system. Liquid secondary coolant for the power cycle flows through the steam generating vessel and is converted to steam by the primary coolant to drive a low pressure turbine of a turbine-generator set. Steam exiting the turbine is condensed and heated prior to return to the steam supply system, thereby completing a secondary coolant flow loop. In one embodiment, a majority of the secondary coolant heating occurs within the steam generating vessel via heat exchange with the primary coolant rather than externally in the secondary coolant flow loop. This creates a temperature differential between the primary and secondary coolant sufficient to create natural thermally induced convective circulation of the primary coolant.
A nuclear steam supply system having a start-up sub-system for heating a primary coolant. In one embodiment, the invention can be a nuclear steam supply system comprising: a reactor vessel having an internal cavity, a reactor core comprising nuclear fuel disposed within the internal cavity; a steam generating vessel fluidly coupled to the reactor vessel; a primary coolant loop formed within the reactor vessel and the steam generating vessel, a primary coolant in the primary coolant loop; and a start-up sub-system fluidly coupled to the primary coolant loop, the start-up sub-system configured to: (1) receive a portion of the primary coolant from the primary coolant loop; (2) heat the portion of the primary coolant to form a heated portion of the primary coolant; and (3) inject the heated portion of the primary coolant into the primary coolant loop.
G21C 15/00 - Cooling arrangements within the pressure vessel containing the coreSelection of specific coolants
G21C 1/32 - Integral reactors, i.e. reactors wherein parts functionally associated with the reactor but not essential to the reaction, e.g. heat exchangers, are disposed inside the enclosure with the core
F22B 1/02 - Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
F01K 5/02 - Plants characterised by use of means for storing steam in an alkali to increase steam pressure, e.g. of Honigmann or Koenemann type used in regenerative installation
28.
Passively-cooled spent nuclear fuel pool system and method therefor
A passively-cooled spent nuclear fuel pool system comprising: a spent nuclear fuel pool comprising a body of liquid water having a surface level, at least one spent nuclear fuel rod submerged therein that heats the water; a lid covering the spent nuclear fuel pool to create a hermetically sealed vapor space between the surface level and the lid; and a passive heat exchange sub-system including a riser conduit comprising first and second riser inlet sections and a primary riser section that receives water vapor therefrom. Each riser inlet section has a respective inlet positioned in a respective section of the vapor space. A downcomer receives and condenses water vapor from the primary section forming condensed water vapor. A return conduit fluidly coupled to the downcomer and having an outlet located in the body of liquid water returns the condensed water vapor thereto.
A portable nuclear fuel cartridge comprising a unitary support structure and a plurality of nuclear fuel assemblies that collectively form a nuclear fuel core. The nuclear fuel core is integrated into the unitary support structure to collectively form a self-supporting assemblage than can be lifted as a single unit. In another aspect, the invention is a method of fueling and/or defueling a nuclear reactor utilizing a nuclear fuel cartridge that is loaded and/or unloaded from the nuclear reactor as a single unit. In another aspect, a nuclear reactor core is provided that comprises a nuclear fuel core comprising; a plurality of first nuclear fuel assemblies, each of the plurality of first nuclear fuel assemblies having a first transverse cross-sectional configuration; and a plurality of second nuclear fuel assemblies, each of the plurality of second nuclear fuel assemblies having a second transverse cross-sectional configuration that is different than the first transverse cross-sectional configuration.
G21C 3/30 - Assemblies of a number of fuel elements in the form of a rigid unit
G21C 5/06 - Means for locating or supporting fuel elements
G21C 1/06 - Heterogeneous reactors, i.e. in which fuel and moderator are separated
G21C 3/32 - Bundles of parallel pin-, rod-, or tube-shaped fuel elements
G21C 5/14 - Moderator or core structureSelection of materials for use as moderator characterised by shape
G21C 11/06 - Reflecting shields, i.e. for minimising loss of neutrons
G21C 19/32 - Apparatus for removing radioactive objects or materials from the reactor discharge area, e.g. to a storage placeApparatus for handling radioactive objects or materials within a storage place or removing them therefrom
A component cooling water system for a nuclear power plant. In one embodiment, the system includes an inner containment vessel housing a nuclear reactor and an outer containment enclosure structure. An annular water reservoir is formed between the containment vessel and containment enclosure structure which provides a heat sink for dissipating thermal energy. A shell-less heat exchanger is provided having an exposed tube bundle immersed in water held within the annular water reservoir. Component cooling water from the plant flows through the tube bundle and is cooled by transferring heat to the annular water reservoir. In one non-limiting embodiment, the tube bundle may be U-shaped.
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
G21C 15/26 - Promoting flow of the coolant by convection, e.g. using chimneys, using divergent channels
G21C 11/08 - Thermal shieldsThermal linings, i.e. for dissipating heat from gamma radiation which would otherwise heat an outer biological shield
A nuclear reactor containment system with passive cooling capabilities. In one embodiment, the system includes an inner containment vessel for housing a nuclear steam supply system and an outer containment enclosure structure. An annular water-filled reservoir may be provided between the containment vessel and containment enclosure structure which provides a heat sink for dissipating thermal energy, in the event of a thermal energy release incident inside the containment vessel, the reactor containment system provides passive water and air cooling systems operable to regulate the heat of the containment vessel and the equipment inside. In one embodiment, cooling water makeup to the system is not required to maintain containment vessel and reactor temperatures within acceptable margins.
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
G21C 9/00 - Emergency protection arrangements structurally associated with the reactor
A nuclear steam supply system utilizing gravity-driven natural circulation for primary coolant flow through a fluidly interconnected reactor vessel and a steam generating vessel. In one embodiment, the steam generating vessel includes a plurality of vertically stacked heat exchangers operable to convert a secondary coolant from a saturated liquid to superheated steam by utilizing heat gained by the primary coolant from a nuclear fuel core in the reactor vessel. The secondary coolant may be working fluid associated with a Rankine power cycle turbine-generator set in some embodiments. The steam generating vessel and reactor vessel may each be comprised of vertically elongated shells, which in one embodiment are arranged in lateral adjacent relationship. In one embodiment, the reactor vessel and steam generating vessel are physically discrete self-supporting structures which may be physically located in the same containment vessel.
A nuclear steam supply system includes an elongated reactor vessel having an internal cavity with a central axis, a reactor core having nuclear fuel disposed within the internal cavity, and a steam generating vessel having at least one heat exchanger section, the steam generating vessel being fluidicly coupled to the reactor vessel. The reactor vessel includes a shell having an upper flange portion and a head having a head flange portion. The upper flange portion is coupled to the head flange portion, wherein the upper flange portion extends into the internal cavity, and the head flange portion extends outward from the internal cavity. Primary coolant flow between the steam generating vessel and reactor vessel occurs via a fluid coupling comprising direct welding between forged outer nozzles of each vessel and welded inner nozzles between each vessel inside the outer nozzles.
A nuclear reactor cooling system with passive cooling capabilities operable during a reactor shutdown event without available electric power. In one embodiment, the system includes a reactor vessel with nuclear fuel core and a steam generator fluidly coupled thereto. Primary coolant circulates in a flow loop between the reactor vessel and steam generator to heat secondary coolant in the steam generator producing steam. The steam flows to a heat exchanger containing an inventory of cooling water in which a submerged tube bundle is immersed. The steam is condensed in the heat exchanger and returned to the steam generator forming a closed flow loop in which the secondary coolant flow is driven by natural gravity via changes in density from the heating and cooling cycles. In other embodiments, the cooling system is configured to- extract and cool the primary coolant directly using the submerged tube bundle heat exchanger.
A nuclear reactor cooling system with passive cooling capabilities operable during a loss-of-coolant accident (LOCA) without available electric power. The system includes a reactor vessel with nuclear fuel core located in. a reactor well. An in-containment water storage tank is fluidly coupled to the reactor well and holds an inventory of cooling water..During a LOCA event, the tank floods the reactor well with water. Eventually, the water heated by decay heat from the reactor vaporizes producing steam. The steam flows to an in- containment heat exchanger and condenses. The condensate is returned to the reactor well in a closed flow loop system in which flow may circulate solely via gravity from changes in phase and density of the water. In one embodiment, the heat exchanger may he an array of heat dissipater ducts mounted on the wall of the inner containment vessel surrounded by a heat sink.
A nuclear reactor in one embodiment includes a cylindrical, body having an internal cavity, a nuclear fuel core, and a shroud disposed in the cavity. The shroud comprises an inner shell, an outer shell and a plurality of intermediate shells disposed between the inner and outer shells. Pluralities of annular cavities are formed between the inner and outer shells which are filled with primary coolant such as demineralized water. The coolant-filled annular cavities may be sealed at the top and bottom and provide an insulating effect to the shroud. In one embodiment, the shroud may comprise a plurality of vertically-stacked self-supported shroud segments which are coupled together.
A nuclear reactor cooling system with passive cooling capabilities operable during a reactor shutdown event without available electric power. In one embodiment, the system includes a reactor vessel with nuclear fuel core and a steam generator fluidly coupled thereto. Primary coolant circulates in a flow loop between the reactor vessel and steam generator to heat secondary coolant in the steam generator producing steam. The steam flows to a heat exchanger containing an inventory of cooling water in which a submerged tube bundle is immersed. The steam is condensed in the heat exchanger and returned to the steam generator forming a closed flow loop in which the secondary coolant flow is driven by natural gravity via changes in density from the heating and cooling cycles. In other embodiments, the cooling system is configured to extract and cool the primary coolant directly using the submerged tube bundle heat exchanger.
G21C 13/02 - Pressure vesselsContainment vesselsContainment in general Details
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
A nuclear reactor cooling system with passive cooling capabilities operable during a loss-of-coolant accident (LOCA) without available electric power. The system includes a reactor vessel with nuclear fuel core located in a reactor well. An in-containment water storage tank is fluidly coupled to the reactor well and holds an inventory of cooling water. During a LOCA event, the tank floods the reactor well with water. Eventually, the water heated by decay heat from the reactor vaporizes producing steam. The steam flows to an in-containment heat exchanger and condenses. The condensate is returned to the reactor well in a closed flow loop system in which flow may circulate solely via gravity from changes in phase and density of the water. In one embodiment, the heat exchanger may be an array of heat dissipater ducts mounted on the wall of the inner containment vessel surrounded by a heat sink.
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
A nuclear power generation system and related power cycle are disclosed, in one embodiment, the system includes primary coolant circulation through a hydraulically interconnected reactor containing nuclear fuel and a steam generating vessel collectively defining a steam supply system. Liquid secondary coolant for the power cycle flows through the steam generating vessel and is converted to steam by the primary coolant to drive a low pressure turbine of a turbine-generator set. Steam exiting the turbine is condensed and heated prior to return to the steam supply system, thereby completing a secondary coolant flow loop. In one embodiment, a majority of the secondary coolant heating occurs within the steam generating vessel via heat exchange with the primary coolant rather than externally in the secondary coolant flow loop. This creates a temperature differential between the primary and secondary coolant sufficient to create natural thermally induced convective circulation of the primary coolant
A nuclear steam supply system having a shutdown system for removing residual decay heat generated by a nuclear fuel core. The steam supply system may utilize gravity-driven primary coolant circulation through hydraulic-ally interconnected reactor and steam generating vessels forming the steam supply system. The shutdown system may comprise primary and secondary coolant systems. The primary coolant cooling system may include a jet pump comprising an injection nozzle disposed inside the steam generating vessel A portion of the circulating primary coolant is extracted, pressurized and returned to the steam generating vessel to induce coolant circulation under reactor shutdown conditions. The extracted primary coolant may further be cooled before return to the steam generating vessel in some operating modes. The secondary coolant cooling system includes a pumped and cooled flow circuit operating to circulate and cool the secondary coolant, which in turn extracts heat from and cools the primary coolant.
G21C 15/02 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements
41.
COMPONENT COOLING WATER SYSTEM FOR NUCLEAR POWER PLANT
A component cooling water system for a nuclear power plant. In one embodiment, the system includes an inner containment vessel housing a nuclear reactor and an outer containment enclosure structure. An annular water reservoir is formed between the containment vessel and containment enclosure structure which provides a heat sink for dissipating thermal energy. A shell-less heat exchanger is provided having an exposed tube bundle immersed in water held within the annular water reservoir. Component cooling water from the plant flows through the tube bundle and is cooled by transferring heat to the annular water reservoir. In one non-limiting embodiment, the tube bundle may be U-shaped
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
A nuclear steam supply system having a start-up sub-system for heating a primary coolant in one embodiment, the invention can be a nuclear steam supply system comprising; a reactor vessel having an internal cavity, a reactor core comprising nuclear fuel disposed within the internal cavity; a steam generating vessel fluidly coupled to the reactor vessel; a primary coolant loop formed within the reactor vessel and the steam generating vessel, a primary coolant in the primary coolant loop; and a start-up sub-system fluidly coupled to the primary coolant loop, the start-up sub-system configured to: (1) receive a portion of the primary coolant from the primary coolant loop; (2) heat the portion of the primary coolant to form a heated portion of the primary coolant; and (3) inject the heated portion of the primary coolant into the primary coolant loop.
A passively-cooled spent nuclear fuel pool system and method therefor. In one embodiment, the invention can be a passively-cooled spent nuclear fuel pool system comprising: a speiri nuclear fuel poo! comprising a body of liquid water having a surface level at least one spent nuclear fuel rod submerged in the body of liquid water that heats the body of liquid water; a lid covering the spent nuclear fuel pool to create a hermetically sealed vapor space between the surface level of the body of liquid water and the lid; and a passive heat exchange sub-system fluidly coupled to the vapor space, the passive heat exchange sub-system configured to: (1) receive water vapor from the vapor space; (2) remove thermal energy from the received water vapor, thereby condensing the water vapor to form a condensed water vapor; and (3) return the condensed water vapor to the body of liquid water.
A control rod drive system (CRDS) for use in a nuclear reactor. In one embodiment, the system generally includes a drive rod mechanically coupled to a control rod drive mechanism (CRDM) operable to linearly raise and lower the drive rod along a vertical axis, a rod cluster control assembly (RCCA) comprising a plurality of control rods insertable into a nuclear fuel core, and a drive rod extension (DRE) releasably coupled at opposing ends to the drive rod and RCCA. The CRDM includes an electromagnet which operates to couple the CRDM to DRE. In the event of a power loss or SCRAM, the CRDM may be configured to remotely uncouple the RCCA from the DRE without releasing or dropping the drive rod which remains engaged with, the CRDM and in position.
G21C 19/20 - Arrangements for introducing objects into the pressure vesselArrangements for handling objects within the pressure vesselArrangements for removing objects from the pressure vessel
45.
NUCLEAR FUEL CORE, NUCLEAR FUEL CARTRIDGE, AND METHODS OF FUELING AND/OR DEFUELING A NUCLEAR REACTOR
A portable nuclear fuel cartridge comprising a unitary support structure and a plurality of nuclear fuel assemblies that collectively form a nuclear fuel core. The nuclear fuel core is integrated into the unitary support structure to collectively form a self-supporting assemblage than can be lifted as a single unit. In another aspect, the invention is a method of fueling and/or defueling a nuclear reactor utilizing a nuclear fuel cartridge that is loaded and/or unloaded from the nuclear reactor as a single unit.
A nuclear steam supply system includes an elongated reactor vessel having an internal cavity with a central axis, a reactor core having nuclear fuel disposed within the internal cavity, and a steam generating vessel having at least one heat exchanger section, the steam generating vessel being fluidicly coupled to the reactor vessel. The reactor vessel includes a shell having an upper flange portion and a head having a head flange portion. The upper flange portion is coupled to the head flange portion, wherein the upper flange portion extends into the internal cavity, and the head flange portion extends outward from the internal cavity.
A nuclear reactor containment system with passive cooling capabilities. In one embodiment, the system includes an inner containment vessel for housing a nuclear steam supply system and an outer containment enclosure structure. An annular water-filled reservoir may be provided between the coatainmetU vessel and containment enclosure structure which provides a heat sink for dissipating thermal energy, in the event of a thermal energy release incident inside the containment vessel., the reactor containment system provides passive water and air cooling systems operable to regulate the heat of the containment vessel and the equipment inside. In one embodiment, cooling water makeup to the system is not required to mainta.in containment vessel and reactor temperatures within acceptable margins.
G21C 15/12 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from pressure vesselArrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements from containment vessel
A nuclear steam supply system utilizing gravity-driven natural circulation for primary coolant flow through a fluidly interconnected reactor vessel and a steam generating vessel. In one embodiment, the steam generating vessel includes a plurality of vertically stacked heat exchangers operable to convert a secondary coolant from a saturated liquid to superheated steam by utilizing heat gained by the primary coolant from a nuclear fuel core in the reactor vessel. The secondary coolant may be working fluid associated with a Rankine power cycle turbine-generator set in some embodiments. The steam generating vessel and reactor vessel may each be comprised of vertically elongated shells, which in one embodiment are arranged in lateral adjacent relationship. In one embodiment, the reactor vessel and steam generating vessel are physically discrete self-supporting structures which may be physically located in the same containment vessel.
G21C 15/02 - Arrangement or disposition of passages in which heat is transferred to the coolant, e.g. for coolant circulation through the supports of the fuel elements
G21C 5/22 - Moderator or core structureSelection of materials for use as moderator characterised by the provision of more than one active zone wherein one zone is a superheating zone
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