1147results 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.

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 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.

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.

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.

An auxiliary system for cooling a spent nuclear fuel pool through a submersible heat exchanger to be located within the pool. In each train or installation, a single loop or series of loops of cooling fluid (e.g., sea water or service water) is circulated. The system is modular, readily and easily installed during an emergency and can be self operating with its own power source. Multiple trains may be used in parallel in order to accomplish the required degree of spent fuel pool cooling required.

A reactor vessel includes a plenum and a reactor core with first and second sets of channels. A blanket salt flows through the first set of channels, and a fuel salt flows through the second set of channels. The plenum receives the blanket salt from the first set of channels. The blanket salt provides a breed-stock for a fission reaction in the fuel salt and transfers heat generated by the fission reaction without mixing with the fuel salt.

The object of the present invention is to provide a core catcher having an integrated cooling path, which comprises a structure able to effectively collect, retain and cool molten core material discharged through a damaged part of a nuclear reactor pressure container during a major incident in a nuclear power station. To this end, the present invention is a core catcher which is disposed underneath the nuclear reactor pressure container in order to retain and cool molten core material discharged through a damaged part of the nuclear reactor pressure container and prevent interaction between the molten core material and the pressure-holding structure of the reactor building during a major incident in the nuclear power station, and which comprises: a main container in the shape of an inverted roof which is provided underneath the nuclear reactor pressure container and collects the molten core material; and a lower structure which is disposed below and outside the main container with supports disposed at scattered points placed in between, thereby forming a cooling path having a predetermined spacing for eliminating the heat of the molten core material.

Disclosed herein is a fully passive decay heat removal system utilizing a partially immersed heat exchanger, the system comprising: a hot pool; an intermediate heat exchanger which heat-exchanges with the sodium of the hot pool; a cold pool; a support barrel extending vertically through the boundary between the hot pool and the cold pool; a sodium-sodium decay heat exchanger received in the support barrel; a sodium-air heat exchanger provided at a position higher than the sodium-sodium decay heat exchanger; an intermediate sodium loop connecting the sodium-sodium decay heat exchanger with the sodium-air heat exchanger; and a primary pump, wherein a portion of the effective heat transfer tube of the sodium-sodium decay heat exchanger is immersed in the cold pool, particularly in a normal operating state, and the surface of the lower end of a shroud for the sodium-sodium decay heat exchanger, the lower end being immersed in the sodium of the cold pool, has perforated holes.

An apparatus and method for mechanically reinforcing the weld between a riser pipe and riser brace of a jet pump assembly are characterized by first and second attachment members for attachment on a riser brace of the jet pump assembly, and first and second clamp bodies respectively pivotally mounted on the attachment members for movement to a clamping position. In the clamping position, respective abutment surfaces of the clamp bodies are forced against a riser pipe that is attached to a yoke of the riser brace. The abutment surfaces apply radial forces to the riser pipe, and the radial forces are reacted by forces applied against the yoke by respective engagement elements of the attachment members whereby the riser pipe and riser brace are clamped together between the abutment surfaces and the engagement elements.

A decay heat removal system for a liquid metal reactor, in which a decay heat exchanger (DHX) is installed concentrically with an intermediate heat-exchanger (IHX) in the same cylinder which separates the DHX and IHX from the reactor pool fluid, and serves to remove the reactor core decay heat. The cylinder surrounds the IHX and the DHX, and has an opened top portion protruded out of the level of the fluid in a hot pool, a bottom portion connected to a cold pool and a guide pipe for allowing the passage of the fluid from the hot pool into the IHX. The decay heat removal system can remove decay heat immediately after occurrence of an accident, thereby improves the safety of a nuclear plant.

The invention discloses a passive residual heat removal system of a marine nuclear power device. The passive residual heat removal system comprises a containment and a cooling heat exchanger. The containment is internally provided with a reactor pressure vessel, a loop cool pipe section, a loop heat pipe section, a steam generator, a refueling water tank, a 1# residual heat removal heat exchanger, a 2# residual heat removal heat exchanger and a cooling water pipe bundle; the refueling water tank is arranged at the top of the containment; the reactor pressure vessel and the steam generator are connected with the heat pipe section through the loop cool pipe section; the inlet and the outlet of the 1# residual heat removal heat exchanger are respectively connected with the loop heat pipe section and the loop cool pipe section; a main steam pipeline and a water supply pipeline which are connected with the inlet and the outlet of the 2# residual heat removal heat exchanger are arranged on the steam generator; upper and lower ends of the cooling water pipe bundle are respectively connected with the inlet and the outlet of the cooling heat exchanger. The passive residual heat removal system of the marine nuclear power device is independent from external power, is improved in capability of removing residual heat of reactor core through natural circulation, is improved in safety redundancy, power and operation stability, and guarantees operation safety of nuclear reactor.

The invention discloses a major accident mitigation system of a nuclear power station on the basis of the nano fluid characteristic, belonging to the technical field of nuclear power station equipment and safety. The system is composed of a superconductive tube, a heat exchanger, a radioactive grain removing device, a nano fluid preparation chamber, an ultrasonic oscillator, an air cooling tower and the like. The system can quickly adsorb energy in a containment under the major accident, hyperpressure in the containment can be alleviated by releasing and removing radioactive air and radioactive aerosol particles, nano particles can be obtained, and the efficient heat exchange medium nano fluid can be prepared to achieve the goal of alleviating the major accident of the reactor and protecting the integrity of the containment structure. A safety control function is performed and finished when major accidents happen. The system has the advantages of good backup safety, simple flow, stable performance and high reliability, is convenient to implement and simple to control, and treats wastes with wastes.

The invention relates to an active and passive nuclear steam supplying system based on 177 reactor core. The nuclear steam supplying system comprises a nuclear reactor core and a reactor coolant system, and is characterized in that the nuclear reactor core comprises 177 nuclear fuel assemblies with the active length of 12-14 feet; and the reactor coolant system comprises a reactor pressure vessel, a main pipe connecting an inlet and an outlet of a reactor coolant, a main pump, a steam generator, a pressure stabilizer and a pressure relief tank. The invention also relates to a nuclear power station employing the above active and passive nuclear steam supplying system based on the 177 reactor core. The power of the assembling unit of the nuclear power station is 1000-1400 MWe, the average availability is more than or equal to 90%, the maximum ground acceleration is 0.3 g, and a containment has a double-layer steel-made structure for resisting bump of large business airplanes. The active and passive nuclear steam supplying system based on the 177 reactor core has the functions of alleviating and preventing severe accidents, and a core measuring meter penetrates into the reactor pressure vessel from top to bottom, so that the active and passive nuclear steam supplying system possesses an active manner and passive manner combined residual heat removal system and a digitalizer control diversity protection system.

The present invention relates to a reactor design technology, and specifically to a passive direct evaporation type cooling system for a double-layer concrete containment. The system comprises a heat exchanger arranged inside a containment, a cooling water tank arranged outside the containment, and a steam water separation device. According to the present invention, the retention time of cooling water in the heat exchanger is increased to force the cooling water to generate a phase change, and a large amount of heat inside the containment is taken away through phase change latent heat of the water; when the temperature of the containment is less than 100 DEG C, natural circulation flow of the system is low or zero; when the severe accident is generated in the nuclear power station and the containment temperature is more than 100 DEG C, water inside the heat exchanger is heated and expands until the water is evaporated, the separated water returns back to the cooling water tank, the steam is discharged into the atmosphere outside the containment, the system is put into operation, and the natural circulation is formed. With the system of the present invention, the whole process does not require intervention by nuclear power station operators, and whether the system is put into operation is automatically selected according to the containment temperature, such that the passive system is completely achieved, the human intervention factor during accident generation is substantially reduced, and the containment cooling function is achieved independent of external energy sources.

The invention discloses passive containment cooling system. The passive containment cooling system comprises a high-position material exchanging water pool used for storing cooling water, an evaporator, an air cooling tower, a plurality of pipes, and a refrigerant, wherein a containment is equipped with a vault; a reactor pressure vessel o is located in the vault; the high-position material exchanging water pool is positioned in the containment and above the vault, and is communicated with the vault through an isolating valve; the evaporator is positioned in the vault; the air cooling tower is positioned outside the containment and is higher than the vault, the pipes are connected between the outlet of the evaporator and the inlet in the upper end of the air cooling tower, and between the outlet in the lower end of the air cooling tower and the inlet of the evaporator; the refrigerant flows in a circulation channel formed among the evaporator, the air cooling tower and the pipes. The passive containment cooling system can realize the function of exporting waste heat of the containment in case of an accident without relying on an external power supply, so as to increase the stability of the system and also the safety of the nuclear power station.

A steam generator system for a pressurized water reactor which employs an external to containment steam drum and recirculation loop piping. The steam generator system changes the arrangement of a typical pressurized water reactor recirculation steam generator by relocating the functions of steam separation and feedwater preheating outside of the reactor coolant system. The steam generator system and thermal hydraulic conditions are selected in order to minimize the size of the steam generator heat exchanger component volume inside of the containment. The external steam drum component can be isolated in accident conditions when desired and is used as a source of secondary fluid inventory for improved decay heat removal capability and tolerance for loss of feedwater events. Thus, the steam generator component volume inside of the containment is reduced and the amount of maintenance required for the reactor coolant system components are similarly reduced.

A containment vessel for containing a reactor pressure vessel and steam generators has a main containment vessel, a diaphragm, a pressure suppression chamber, LOCA vent pipes. The reactor pressure vessel contains a reactor core of a pressurized water reactor. The diaphragm partitions the main containment vessel into an upper vessel and a lower vessel. The pressure suppression chamber has a suppression pool to store water and gas phase of the pressure suppression chamber communicates with the upper vessel. The LOCA vent pipes connect the pressure suppression chamber to the lower vessel. All of the equipments and piping that constitute the reactor pressure boundary, including the reactor pressure vessel, the steam generators, a cold leg pipe and a hot leg pipe, are contained in the lower vessel.

A core spray sparger T-box attachment assembly for a nuclear reactor pressure vessel, wherein the pressure vessel includes a shroud, a sparger T-box penetrating the shroud, a plurality of sparger distribution header pipes coupled to the sparger T-box, and a downcomer pipe. The sparger header pipes may include at least one sparger nozzle, and the sparger T-box attachment assembly may include a downcomer pipe coupling and a sparger T-box clamp. The sparger T-box clamp may include an anchor plate having a draw bolt opening to receive a draw bolt, a first clamp block substantially aligned at one end of the anchor plate, and a second clamp block substantially aligned at the other end of the anchor plate.

The invention discloses a non-active multi-functional ponded stabilivolt system of atomic reactor, which comprises the following parts: high-pressure pond, air cavity on the interior of high-pressure pond, level measuring channel made of concrete structure in the air cavity, wherein the injecting pipe is set on the bottom of high-pressure pond to connect the reacting pile inlet cavity with stop valve on the injecting pipe; the fluctuating pipe is set on the bottom of the high-pressure pond to connect the main pump inlet; the rising pipe is set in the middle of the high-pressure pond to connect the reacting pile output cavity with pneumatic separating valve on the rising pipe; the small-flow circulating pipeline is set on the rising pipe between pneumatic separating valve and reacting pile output cavity, which connects the main pump inlet pipe. The invention improves the safety of reacting pile, which reduces the building and operating cost greatly with wide applying prospect.