Abstract: A nuclear power system includes a reactor vessel that includes a reactor core mounted within a volume of the reactor vessel. The reactor core includes one or more nuclear fuel assemblies configured to generate a nuclear fission reaction. The nuclear power system further includes a containment vessel sized to enclose the reactor vessel such that an open volume is defined between the containment vessel and the reactor vessel. A boron injection system is positioned in the open volume of the containment vessel and includes an amount of boron sufficient to stop the nuclear fission reaction or maintain the nuclear fission reaction at a sub-critical state. The boron injection system is positioned to deliver the amount of boron into the open volume.

Abstract: A system and a method for a passive containment vent system for a Boiling Water Reactor (BWR). The system is capable of venting and scrubbing a gaseous discharge from the primary containment of the BWR over a prolonged period of time leading up to or following a serious plant accident, without the need for monitoring by on-site plant personnel. External electrical power is not required (following initial activation of the system) in order to operate the containment vent system. The system may protect the integrity of primary containment during and following the serious plant accident.

Abstract: A nuclear engineering plant has a containment, whose interior chamber is subdivided by a wall into a systems chamber and an operating chamber which is accessible during normal operation. The containment ensures a particularly high operational reliability, in particular also in incident situations, in which hydrogen is released in the systems chamber. For this purpose, a number of overflow openings are provided in the partition wall, the respective overflow opening is closed by a closure element of a closure apparatus which opens automatically when a trigger condition associated with the respective overflow opening is reached. Closure apparatuses are provided which open both as a function of pressure and independently of pressure. The closure apparatus furthermore has a closure element containing a bursting film or a bursting diaphragm. The closure apparatus is configured such that it frees the overflow opening automatically when a predetermined environment-side trigger temperature is reached.

Abstract: The Seafloor Power Station is one or more unmanned electric power generating Units (2) sending power to and operated from existing coastal sites by a manned facility (1) by connecting lines and hoses (3) delivering power to a grid by lines (4). Each Unit's hull (11) maintained in a vacuum, contains both nuclear steam and electricity generating systems. The hull functions as overpressure containment and as condenser in the event of a loss of coolant accident or other steam release. The Units operate submerged in very cold water, with depth set by remotely controlled vertical mooring systems, mounted on gravity mats (27). A Unit must be surfaced by its mooring system to refuel the reactor, an action both conspicuous and public, enabling international oversight of the fuel disposition.

Abstract: A head assembly of a reactor pressure vessel in an ice condenser plant is retrofitted to permit the assembly to be removed during a later refueling operation in reduced time and with reduced exposure to radiation by operating personnel. The portions of the ductwork ventilation system that originally provided cooling air to CRDMs are removed below the seismic support platform. The original CRDM cooling shroud that surrounds the lower portion of the CRDM assemblies is extended to the seismic support platform. A plenum is mounted on the seismic support platform and in air flow communication with interior portion of the extended CRDM cooling shroud. The plenum fits under the missile shield. Spool pieces are connected between the plenum and the portion of the ductwork adjacent to the seismic support platform.

Abstract: A seismically isolated liquid metal reactor power block is described. In one embodiment, the liquid metal reactor power block is a substantially rectangular nuclear plant with two nuclear islands and a common liquid metal service facility commonly supported on a seismic isolation platform near grade level. The seismic isolation platform supports the nuclear islands in a mirror-symmetric arrangement on opposite sides of a shared liquid metal service facility. A containment pressure suppression system connects the primary pressure relief volumes of the containment structures of each nuclear island to that of the other and also to a common pressure relief volume in the liquid metal service facility, thereby reducing the pressure load on each individual containment structure.

Abstract: A nuclear reactor includes a propagation space for core melt. The propagation space has a coolant conduit leading to a coolant reservoir and a device which opens in a temperature-dependent manner. The coolant conduit in the propagation space is a spray conduit having a spraying area which covers the cross-section of the propagation space over a large area. The device is controlled in such a way that it opens when the core melt enters the propagation space. Spraying gives rise to a crust on the core melt which reduces heat radiation. At the same time, the propagation space fills with a steam atmosphere which drastically reduces the thermal load on building structures.

Abstract: A nuclear power plant has a reactor core and a containment chamber for receiving core melt of the reactor core. A cooling system for cooling the containment chamber includes a flooding container to be filled with coolant fluid. A cooling pipe leads from the flooding container to the containment chamber. A passively opening closure element closes the cooling pipe in the flooding container and opens as a function of a level of the coolant fluid.

Abstract: A device for collecting and cooling reactor-meltdown products from a reactor pressure vessel includes an antechamber disposed below the reactor pressure vessel and an expansion chamber for the reactor-meltdown products. A channel which is disposed between the antechamber and the expansion chamber has a partition being destructible by the reactor-meltdown products. A closure element which connects a coolant reservoir to the expansion chamber is destructible by the reactor-meltdown products. A method for collecting and cooling reactor-meltdown products from a reactor pressure vessel includes collecting reactor-meltdown products in an antechamber disposed below the reactor pressure vessel and keeping them in the antechamber for a predetermined time interval. A partition disposed between the antechamber and an expansion chamber is destroyed with the reactor-meltdown products. The reactor-meltdown products penetrate from the antechamber into the expansion chamber and are spread in the expansion chamber.

Abstract: A device for collecting reactor-meltdown products from a reactor pressure vessel includes an antechamber disposed below the reactor pressure vessel, an expansion chamber having a floor forming an expansion surface for reactor-meltdown products, and a bulkhead being disposed between the antechamber and the expansion chamber and being destructible by the reactor-meltdown products. The bulkhead has a plurality of parts including at least one part being thermally destructible by the reactor-meltdown products. The at least one part is joined to the other parts for clearing a flow path for the reactor-meltdown products from the antechamber into the expansion chamber upon a destruction of the at least one part.

Abstract: A nuclear reactor facility has a collecting chamber for a core melt, a coolant tank and a coolant connecting line having an inlet end connected to the coolant tank and an outlet end protruding into the collecting chamber and having an outlet cross section. A closing device at the connecting line which opens as a function of temperature for initiating cooling of the core melt includes a closing member disposed at the outlet end of the connecting line for normally tightly closing the outlet end. The closing member has a temperature-dependent opening element for tripping clearance of at least a portion of the outlet cross section of the connecting line upon thermal action by the core melt to direct the coolant from the coolant tank, through the connecting line and into the collecting chamber. The opening element being a plastic block which thermally insulates the coolant, and is corrosion-resistant.

Abstract: A nuclear reactor has a core and a pressure vessel with a wall and an interior. A pressure relief responding as a function of temperature is provided in the case of insufficient core cooling (due to a highly improbable failure of the cooling devices and emergency cooling devices). A safety device protecting against overpressure failure of the pressure vessel upon insufficient cooling of the core includes a pressure pipe passing pressure-tightly through the wall and extending into the interior of the pressure vessel. The pressure pipe has at least one pressure compensation opening formed therein in the interior of the pressure vessel and has a fusible sealing body sealing the pressure compensation opening. The fusible sealing body is formed of a melting solder melting at a limit temperature, such as 600.degree. to 700.degree. C., and unblocking the pressure compensation opening, but keeping the pressure compensation opening sealed during normal operation.

Abstract: A nuclear reactor has a pressure vessel with an interior, a coolant conducting surface, such as a wall of the pressure vessel or a line passing through the wall of the pressure vessel, a pressure relief line, and a core. A safety device which protects the pressure vessel against overpressure failure upon inadequate cooling of the core includes a pressure relief valve being pressure-tightly inserted into the coolant conducting surface and having a seat, a closure element normally disposed on the seat for blocking a flow from the interior of the pressure vessel to the pressure relief line, an abutment, and a valve closing spring holding the closure element and being supported against the abutment. A force transmission element holds the abutment and has an end facing away from the abutment. A detent is disposed in the pressure vessel and fixes the end of the force transmission element. The detent is releasable in dependence on a given threshold temperature, for example 700.degree. C.

Abstract: A bracket for attaching at least one vibrator to an ice basket of a pressurized water reactor includes a horizontally extending first armature portion and a horizontally extending second armature portion pivotably attached to the second armature portion. The first and second armature portions have clamps extending downwardly from each of their ends, and each of the clamps includes an arcuate groove extending vertically upwardly from its bottom surface to engage the rim of the ice basket. An attachment portion extends vertically upwardly from and is formed unitarily with the first armature portion, the vibrators being attached to the sides of the attachment portion. The clamps extending from the second armature portion are pivotably connected to and are also laterally adjustable with respect to the first and second ends of the second armature portion.

Abstract: A vibrating assembly for vibrating an ice basket of a pressurized water reactor comprises first and second vibrators and a bracket operatively connected to the vibrators. The bracket includes a horizontally extending first armature portion and a horizontally extending second armature portion pivotably attached to the second armature portion. The first and second armature portions have clamps extending downwardly from each of their ends, and each of the clamps includes an arcuate groove extending vertically upwardly from its bottom surface to engage the rim of the ice basket. An attachment portion extends vertically upwardly from and is formed unitarily with the first armature portion, the vibrators being attached to the sides of the attachment portion. The clamps extending from the second armature portion are pivotably connected to and are also laterally adjustable with respect to the first and second ends of the second armature portion.

Abstract: A safety device against overpressure failure of a nuclear reactor pressure vessel in case of inadequate core cooling, includes a pressure relief system responding as a function of temperature. A differential-pressure-loaded pressure relief valve set in a wall or an immediately adjacent pipeline of the pressure vessel which is exposed to primary pressure, has a closure piece that is preferably a differential-pressure piston being mounted so as to be longitudinally displaceable and being sealingly retained in a closure position thereof by a fusible stop. When an upper threshold temperature is reached in the interior of the reactor, which causes the fusible stop to melt due to a threshold temperature heat flow reaching the stop, the differential-pressure piston is moved into an opened position thereof.

Abstract: A vibrating assembly for vibrating an ice basket of a pressurized water reactor comprises first and second vibrators and a bracket operatively connected to the vibrators. The bracket includes a horizontally extending first armature portion and a horizontally extending second armature portion pivotably attached to the second armature portion. The first and second armature portions have clamps extending downwardly from each of their ends, and each of the clamps includes an arcuate groove extending vertically upwardly from its bottom surface to engage the rim of the ice basket. An attachment portion extends vertically upwardly from and is formed unitarily with the first armature portion, the vibrators being attached to the sides of the attachment portion. The clamps extending from the second armature portion are pivotably connected to and are also laterally adjustable with respect to the first and second ends of the second armature portion.

Abstract: The invention as presented consists of a submerged passively-safe power station including a pressurized water reactor capable of generating at least 600 MW of electricity, encased in a double hull vessel, and provides fresh water by using the spent thermal energy in a multistage flash desalination process.

Abstract: A nuclear reactor complex includes fusible plugs to prevent water from a wetwell from flowing into a drywell including the reactor vessel. In case the core overheats and molten corium falls to the drywell floor, the heat from the corium melts the fusible plugs and water floods the drywell. The water inhibits a corium-concrete reaction, minimizing pressure increase within the drywell and thus the chances of radioactive materials being released into the environment.

Abstract: Apparatus for the controlled venting of gases from the containment housing of a chemical or nuclear reactor. The vent path is configured as a manometer filled with a low melting point metal. Gases passing through the manometer are exhausted to a tank of scrubbing solution where toxic materials are removed prior to venting the gases from the containment housing.

Abstract: A tool for maintaining ice baskets associated with a nuclear reactor system. The frame of the tool includes a platform which is disposed on a lattice support structure surrounding a selected and isolated basket. The tool includes an electric drill mounted for vertical reciprocation, in parallel axial relationship with the ice basket, and plural, selectively connectable auger shaft sections having a continuous helical fin thereabout which are connected in succession between the drill and a rotary drill bit, for drilling a hole of the required length, down through the ice within the ice basket. The drill then is maintained at an upper, vertically fixed position and a funnel positioned about the auger; ice chips or flakes are fed into the funnel while the drill is driven in reverse rotation, the auger conveying the ice to the bottom of the ice basket for filling lowermost voids and for filling successively higher voids as the auger is withdrawn.

Abstract: Removable cruciforms are selectively installed at predetermined, spaced elevations within ice baskets associated with a nuclear power system, each ice basket having a generally cylindrical sidewall with plural, annular retaining rings secured therein at predetermined, spaced elevations, each cruciform being installed at predetermined, axially displaced elevations, engaging a corresponding annular retaining ring. Each cruciform comprises a pair of brackets joined together between parallel base portions by respective support plate assemblies and slide plates in telescoping, sliding relationshp, defining with the base portions, a spring housing of generally square configuration within which a generally C-shaped spring is received. A pair of legs extends integrally from the longitudinal edges of the base portion of each bracket, angularly disposed so as to extend radially within the ice basket.

Abstract: A tool for maintaining ice baskets associated with a nuclear reactor system. The frame of the tool includes a platform which is disposed on a lattice support structure surrounding a selected and isolated basket. The tool includes an electric drill mounted for vertical reciprocation, in parallel axial relationship with the ice basket, and plural, selectively connectable auger shaft sections having a continuous helical fin thereabout which are connected in succession between the drill and a rotary drill bit, for drilling a hole of the required length, down through the ice within the ice basket. The drill then is maintained at an upper, vertically fixed position and a funnel positioned about the auger; ice chips or flakes are fed into the funnel while the drill is driven in reverse rotation, the auger conveying the ice to the bottom of the ice basket for filling lowermost voids and for filling successively higher voids as the auger is withdrawn.

Abstract: A pressurized water reactor system having circulation means outside the containment vessel for the circulation of loss of coolant emergency water is provided which prevents exposure of such water to the atmosphere. The system includes an enclosure, separate from the containment vessel, the interior of the enclosure being sealed to the atmosphere and containing a pumping means, and encased inlet and outlet conduits communicating between the interior of the containment vessel and the pump means within the enclosure. The enclosure may also contain a heat exchange means, while the emergency water storage tank can be positioned in the containment vessel, in the enclosure, or separate from both. Provision is also made for use of the pump in the enclosure for circulation of residual heat removal coolant water.