2747results about "Cooling arrangement" patented technology

A power module assembly includes a reactor core immersed in a coolant and a reactor vessel housing the coolant and the reactor core. An internal dry containment vessel submerged in liquid substantially surrounds the reactor vessel in a gaseous environment. During an over-pressurization event the reactor vessel is configured to release the coolant into the containment vessel and remove a decay heat of the reactor core through condensation of the coolant on an inner surface of the containment vessel.

The invention belongs to safety equipment for a nuclear power plant, in particular to a passive and active combined special safety system for the nuclear power plant. The system comprises a passive high-pressure core water supply tank, an accumulator, a low-pressure safety injection pump, a refueling water tank, a secondary-side passive residual heat removal heat exchanger, a vapor condensation water tank, a containment spray system, a passive reactor cavity water injection system, related valves and related pipes. When the nuclear power plant has a design basis accident or beyond design basis accident, through a series of passive and active safety facilities used in all steps, the circuit of a reactor and the core can be cooled effectively, so that the nuclear power plant can enter a safe cold shutdown condition smoothly; and thus, the serious accident consequence of the reactor is inhibited or relieved, damage caused by accidents is relieved, and the safety of the nuclear power plant is improved.

A power module assembly includes a reactor vessel containing a reactor core surrounded by a primary coolant. A containment vessel is adapted to be submerged in a containment cooling pool and to prohibit a release of the primary coolant outside of the containment vessel. A secondary cooling system is configured to remove heat generated by the reactor core. The heat is removed by circulating liquid from the containment cooling pool through the primary coolant.

The invention belongs to a containment cooling system, in particular, to a high-capacity and fully passive containment cooling system. The containment cooling system is used for collecting thermotechnical parameters related to the containment by using a sensor and tracking a cooling process; a plurality of storage boxes for storing different coolants is arranged above the containment; the dynamic control of containment cooling power can be realized by choosing the types of the coolants and adjusting the flows of the coolants; and by using a generalized passive control unit, the start-up and the whole running process of the containment cooling system can be completely independent on external power supply, thus the containment cooling system has a characteristic of fully passiveness.

The invention relates to an active-passive combined reactor core residual heat removal system for a nuclear power station. The active-passive combined reactor core residual heat removal system comprises a safety injection system, a containment spraying system, an auxiliary water supply system, a reactor cavity water injection system, a secondary side passive residual heat removal system, a passive containment heat leading-out system and related valves and pipelines. The active-passive combined reactor core residual heat removal system provided by the invention realizes three safety functions of controlling reactivity, discharging reactor core heat and containing radioactive substance when an accident occurs in an active-passive combined multi-redundancy diversity manner. The active-passive combined reactor core residual heat removal system provided by the invention can completely realize the safety functions of safety injection and safety spraying under the condition that the accident occurs in a nuclear power plant, reactor cavity water injection under the serious accident working condition and the like, effectively improve reliability of a safety system, enhance coping capability of the safety system under the working condition that the accident occurs in the nuclear power station, can effectively prevent and relieve the serious accident, reduce the reactor core melting probability and risk probability of large-scale radioactivity release and greatly improve safety performance of the nuclear power station.

A system includes a containment vessel configured to prohibit a release of a coolant, and a reactor vessel mounted inside the containment vessel. An outer surface of the reactor vessel is exposed to below atmospheric pressure, wherein substantially all gases are evacuated from within the containment vessel.

A passive safety system includes a containment, a reactor in the containment, a plurality of safety injection tanks connected with the reactor and having water and nitrogen gas to supply water thereof into the reactor through a safety injection line communicating to the first safety injection line upon a loss of coolant accident, a plurality of core makeup tanks connected with the reactor to supply water thereof into the reactor through a second safety injection line communicating to a safety injection line upon the loss of coolant accident, and a plurality of passive residual heat removal systems to remove residual heat from the reactor upon the loss of coolant accident or a non-loss of coolant accident. The water in each of the safety injection tank is stably supplied to the reactor for many hours by a differential head resulting from gravity or gas pressure.

An in-core restraint assembly is for a nuclear reactor core including an upper core plate, a lower core support plate and a plurality of fuel assemblies extending longitudinally therebetween. Each fuel assembly includes top and bottom nozzles and a plurality of elongated fuel rods extending therebetween. The in-core restraint assembly includes a first restraint element, such as a spring pack, coupled to the upper core support plate and providing a substantially axial compressive force on the top nozzle of the fuel assembly. An optional second restraint element is structured to be coupled to the lower core plate in order to engage and further restrain the fuel assembly proximate the bottom nozzle. The second restraint element includes a pin member extending from the bottom nozzle of the fuel assembly and received in a socket coupled to the lower core support plate, whereby this mating sustains a longitudinal (vertical) frictional force which must be overcome before fuel assembly lift off can occur.

The invention relates to a safety injection system, which is used for mitigating an accident and protecting the safety of a reactor core of a nuclear power plant and comprises a high-pressure safety injection pump, a low-pressure safety injection pump, a safety injection tank and a refueling water tank for containing safety injection water, wherein the refueling water tank is positioned in a safety shell of the nuclear power plant; the safety injection tank is connected on a direct pressure vessel injection pipeline by a pipeline provided with a control valve; the high-pressure safety injection pump is connected between the refueling water tank and the direct pressure vessel injection pipeline by a pipeline provided with a control valve; and the low-pressure safety injection pump is connected between the refueling water tank and the direct pressure vessel injection pipeline by a pipeline provided with a control valve. The safety injection system has the advantages of reducing cross pipelines of the system, realizing continuous operation, simplifying the system operation, also strengthening mitigating capability of the system for the serious accident and improving safety of the nuclear power plant.

The invention provides a large-scale passive nuclear plant reactor core catcher with bottom water injection and external cooling. The catcher comprises a reactor cavity coating the lower middle part of a reactor pressure vessel, and a reactor cavity concrete soleplate is formed at the bottom of the reactor cavity; a refractory layer is formed on the side surface of the reactor cavity and the bottom of the reactor cavity concrete soleplate; a steel cylinder is sleeved outside the refractory layer; an external cooling passage is formed at the bottom of the steel cylinder, and a cooling passage inlet and a cooling passage outlet are respectively formed at the two outward-extending ends of the external cooling passage; and dozens of nozzles are fixed at the bottom of the steel cylinder, and the upper ends of the nozzles extend into the reactor cavity concrete soleplate while the lower ends of the nozzles extend into the external cooling passage. According to the invention, the dilution and the temperature reduction of a melt are implemented through the melting of concrete by adopting the reactor cavity concrete soleplate as a sacrificial material. A reactor core melt is collected in the refractory layer after the reactor cavity concrete soleplate is molten through, so that the security and the reliability of a nuclear plant are further improved.

This disclosure describes nuclear fuel salts usable in certain molten salt reactor designs and related systems and methods. Binary, ternary and quaternary chloride fuel salts of uranium, as well as other fissionable elements, are described. In addition, fuel salts of UCl_xF_y are disclosed as well as bromide fuel salts. This disclosure also presents methods and systems for manufacturing such fuel salts, for creating salts that reduce corrosion of the reactor components and for creating fuel salts that are not suitable for weapons applications.

The invention provides a combined square fuel assembly, a reactor core and a two-pass flowing method of a moderator and a coolant, which are suitable for a super-critical water reactor. The fuel assembly consists of 4 same child components arranged in a 2*2 square form, wherein each child component consists of multiple fuel rods arranged in a square grid form, a water rod is arranged in a central area, and a guide tube of a crossed control rod and a conduit of the water rod are placed above the component and a conduit of the water rod and a moderator duct are placed below the component; the reactor core is divided into first and second pass areas; the moderator flows into the space between the water rod and the child component from top to bottom in both passes; the coolant flows into a first pass fuel area from top to bottom; and the moderator and the coolant flow into a second pass fuel area from bottom to top after being stirred and mixed below the reactor core and flow out of the reactor core. According to the combined square fuel assembly, the reactor core and the two-pass flowing method of the super-critical water reactor, the moderator and the coolant as well as the different pass coolants in the components and the reactor core can be effectively shunted when the fuel rod is fully and uniformly moderated, the structural materials are reduced and the feasibility and safety are high.

The invention relates to reactor design technology, in particular to a passive heat removal device for dealing with a station blackout accident. The passive heat removal device structurally comprises a secondary side passive residual heat removal system and a passive containment heat export system, and the secondary side passive residual heat removal system is used for exporting residual heat of a reactor core and sensible heat of various devices of a reactor coolant system, so that a reactor is maintained to be in a safe shutdown state. The passive containment heat export system is used for exporting heat in a containment released by the reactor core so as to maintain integrity of the containment. The secondary side passive residual heat removal system and the passive containment heat export system share a hot water tank. The passive heat removal device for dealing with the station blackout accident is capable of exporting decay heat of the reactor core and heat in containment space released by the reactor core under the working condition of the station blackout accident, and melting probability of the reactor core and probability of radioactive substances released to the environment are evidently lowered.

A nuclear power plant with an improved cooling system using nanoparticles in solid or fluid form is provided. The nanoparticles are delivered in locations such as the cold leg accumulator and high and low pressure pumps of an emergency core cooling system. Motor driven valves and pressurization can aid in the delivery. Methods for providing the nanoparticles are also provided.

In a nuclear reactor internal structure, generation and promotion of object-downstream separating vortices are suppressed so that coolant uniformly flows in a reactor core and pressure loss of flow of the coolant is reduced so that the flow of the coolant is stabilized. A lower connecting plate 30 arranged in a lower plenum 8 comprises a ring portion 31 in which an arcuate portion 32 and a cut-off portion are alternately formed. An outer peripheral portion of the ring portion 31 is asymmetric relative to a flow direction of main flow and also asymmetric relative to a separating flow generation direction.

A combinatorial heterogeneous-homogeneous reactor configuration in which an array or groups of homogeneous fuel assemblies are interlinked together in a heterogeneous lattice. The present invention removes the limitation of a homogeneous reactor by providing a reactor concept that utilizes the inherent advantages of homogeneous fuel elements but in a heterogeneous fuel lattice arrangement that limits the power density of any one homogeneous fuel element and yet forms a reactor arrangement that is capable of producing any product demand of interest. The present invention provides a method for producing medical isotopes by the use of a modular reactor core comprised of homogeneous fuel assemblies arranged in a regular rectangular or triangular pitch lattice. The aqueous fuel solution is contained within individual fuel assemblies that are right circular cylinders clad in corrosion-resistant alloys such as stainless steel, zircalloy, zircalloy alloys, or other metal alloys that are resistant to corrosive fissile environments but preserve neutron economy. The fuel assemblies are supported below by a core plate that is tied directly to the lower reactor support structure. The bottom of each assembly opens into a common plenum area which provides a hydrodynamic communication/coupling path between the individual assemblies in the lattice. The fuel assemblies are supported above by an upper plate that is welded to each assembly tube. The top of each assembly opens to a common upper plenum which provides a means of thermodynamic pressure equalization among the four assemblies in the reactor core lattice.

The invention belongs to a nuclear power station safety system, and in particular relates to a nuclear power station non-active engineering safety system. The system comprises a secondary non-active residual heat removal exchanger, a steam condensation water tank, a non-active reactor cavity water injection system, a non-active high pressure reactor core water supplementing tank and related valves and pipelines. When a nuclear power station is in a design basis accident or a hyper design basis accident, a series of non-active and active safety devices are invested in steps, and a reactor primary circuit and a reactor core are timely, rapidly and effectively cooled, thus a nuclear power station smoothly enters into a safe cold shut-down amplifier state, a reactor disaster consequence is inhibited or alleviated, incident harm is reduced, and the safety of the nuclear power station is improved.

The present invention relates to a fast reactor type coupling nuclear reaction implementation method and a nuclear reactor for same. The main contents comprise: a fast reactor type coupling nuclear reaction implementation method, a reactor modular design approach, a fast reactor type coupling nuclear reactor, a reactor core, a fuel element, a nuclear control system, and a proliferation fuel system. The fast reactor type coupling nuclear reactor mainly combusts thorium and nuclear waste, and has inherent security. The reactor main container is composed of a fission pool and a moderating pool that are completely isolated from each other but coupling to each other. A primary coolant is separated from a moderator. A thermal insulation layer is disposed between the fission pool and the moderating pool so that both can perform neutron exchange but heat exchange is blocked. Fast neutrons produced by the fission pool and moderated neutrons reflected by the moderating pool may enable the reactor core to simultaneously perform coupling nuclear reaction of the two types of neutrons. The moderating pool may be provided with the nuclear control system, and ex-core coupling core control may be implemented. The moderating pool is provided with a thorium purification fuel system, and on-line extraction of the purification fuel can be performed, and separation of nuclide is safe and simple, thereby providing a solution to the technical bottleneck of "thorium reactor".

The reactor vessel of a nuclear reactor installation which is suspended from the cold leg nozzles in a reactor cavity is provided with a lower thermal insulating barrier spaced from the reactor vessel that has a hemispherical lower section that increases in volume from the center line of the reactor to the outer extent of the diameter of tiie thermal insulating barrier and smoothly transitions up the side walls of the vessel. The space between the thermal insulating harrier and the reactor vessel forms a chamber which can be flooded with cooling water through passive valving to directly cool the reactor vessel in the event of a severe accident. The passive inlet valve for the cooling water includes a buoyant door that is normally maintained sealed under its own weight and floats open when the cavity is Hooded. Passively opening steam vents are also provided.

A molten salt reactor is described that includes a containment vessel, a reactor core housed within the containment vessel, a neutron reflector spaced from the containment vessel and positioned between the core and the containment vessel, a liquid fuel comprised of a nuclear fission material dissolved in a molten salt enclosed within the core, a plurality of heat transfer pipes, each pipe having a first and a second end, wherein the first end is positioned within the reactor core for absorbing heat from the fuel, a heat exchanger external to the containment vessel for receiving the second end of each heat transfer pipe for transferring heat from the core to the heat exchanger, and at least one and preferably two or more reactor shut down systems, where at least one may be a passive system and at least one or both may be an active or a manually operated system. The liquid fuel in the core is kept within the core and heat pipes are used to carry only the heat from the liquid core to the heat exchanger.

A jet pump diffuser weld repair device includes a lower ring section and an upper ring section respectively sized to fit around a circumference of the diffuser on opposite sides of the weld to be repaired. The lower and upper ring sections are provided with a plurality of aligned gripper slots. A corresponding plurality of grippers are fit into the gripper slots, where at least one of the gripper slots and the grippers defines cam surfaces shaped to drive the grippers radially inward as lower and upper ring sections are drawn toward each other. A plurality of connector bolts are secured between the lower ring section and the upper ring section. Tightening of the connector bolts draws the lower and upper ring sections toward each other.