Liquid Control Component Patents (Class 376/328)
  • Patent number: 11056246
    Abstract: A channel type heterogeneous reactor core for a heavy water reactor for burnup of thorium based fuel is provided. The heterogeneous reactor core comprises at least one seed fuel channel region comprising seed fuel channels for receiving seed fuel bundles of thorium based fuel; and at least one blanket fuel channel region comprising blanket fuel channels for receiving blanket fuel bundles of thorium based fuel; wherein the seed fuel bundles have a higher percentage content of fissile fuel than the blanket fuel bundles. The seed fuel channel region and the blanket fuel channel region may be set out in a checkerboard pattern or an annular pattern within the heterogeneous reactor core. Fuel bundles for the core are also provided.
    Type: Grant
    Filed: November 17, 2017
    Date of Patent: July 6, 2021
    Assignee: ATOMIC ENERGY OF CANADA LIMITED
    Inventor: Blair P. Bromley
  • Patent number: 10872702
    Abstract: Control rod drives include linearly-moveable control elements inside an isolation barrier. Control rod drives move the control element through secured magnetic elements subject to magnetic fields. Induction coils may generate the magnetic fields across a full stroke length of the control element in the reactor. A closed coolant loop may cool the induction coils, which may be in a vacuum outside the isolation barrier. A control rod assembly may house the magnetic elements and directly, removably join to the control element. The control rod assembly may lock with magnetic overtravel latches inside the isolation barrier to maintain an overtravel position. Overtravel release coils outside the isolation barrier may release the latches to leave the overtravel position. Methods of operation include selectively energizing or de-energizing induction coils to drive the control element to desired insertion points, including full insertion by gravity following de-energization.
    Type: Grant
    Filed: June 30, 2017
    Date of Patent: December 22, 2020
    Assignee: GE-HITACHI NUCLEAR ENERGY AMERICAS LLC
    Inventors: Kenneth A. Morgan, David L. Major, Randy M. Brown
  • Patent number: 10643755
    Abstract: The invention relates to nuclear reactor protection systems and can be used when building nuclear reactors, in particular, the fast neutron reactors. The Technical result of the invention consists in the expansion of 5 functional capabilities of the negative reactivity passive insertion device by securing its reliable actuation in various emergency conditions. The device has two vessels located in a common enclosure one under another with a ring-shape hollow space between the vessels and the enclosure to let the heat carrier flow. Fuel elements are located in the ring-shape hollow space, as well as the tooling for the heat carrier flow formation to cool the fuel elements and heat the upper vessel. The upper vessel is located above the reactor core and is divided with an internal partition wall to the central cylindrical and ring-shape hollow spaces. The partition wall has low thermal conductivity in the transverse direction.
    Type: Grant
    Filed: April 5, 2016
    Date of Patent: May 5, 2020
    Assignee: STATE ATOMIC ENERGY CORPORATION “ROSATOM” ON BEHALF OF THE RUSSIAN FEDERATION
    Inventors: Igor Sergeevich Slesarev, Viktor Nikolaevich Leonov, Boris Borisovich Kubintsev, Elena Aleksandrovna Rodina, Yuriy Vasilevich Chernobrovkin, Aleksey Borisovich Shevchenko
  • Patent number: 9281087
    Abstract: A mobile boration system (60) has a number of components that are mobile and include a water source (10), H2BO3 powder supply (14), a mixer to mix the solution (20) capable of providing a boric acid solution (30) with minimal air entrainment and optional heat exchanger(s) (12), and wherein the system (60) is capable of transport to a nuclear power plant facility by land, sea or air, rather than being in place in a large vulnerable footprint.
    Type: Grant
    Filed: March 5, 2015
    Date of Patent: March 8, 2016
    Assignee: Westinghouse Electric Company LLC
    Inventors: Stephen R. Swantner, Ryan T. Vanston, Robert S. Fournier
  • Patent number: 9266756
    Abstract: A mobile boration system (60) has a number of components that are mobile and include a water source (10), H2BO3 powder supply (14), a mixer to mix the solution (20) capable of providing a boric acid solution (30) with minimal air entrainment and optional heat exchanger(s) (12), and wherein the system (60) is capable of transport to a nuclear power plant facility by land, sea or air, rather than being in place in a large vulnerable footprint.
    Type: Grant
    Filed: March 11, 2013
    Date of Patent: February 23, 2016
    Assignee: Westinghouse Electric Company LLC
    Inventors: Stephen R. Swantner, Ryan T. Vanston
  • Patent number: 9240252
    Abstract: An assembly is provided including a mobile structure including a main pipe equipped with a first end intended to be connected to a water supply and a second end intended to be connected to a circuit connected to the primary circuit of the reactor, and including between these two ends in the direction of circulation of the water, a pump, a water heating device, an injector for continuously injecting the powdered neutron-absorbing element into the water of the main pipe, a first mixer for mixing and dissolving powder with water and a controller driving and controlling the flow rate of the water and the flow rate of the powder injected.
    Type: Grant
    Filed: November 30, 2012
    Date of Patent: January 19, 2016
    Assignee: AREVA NP
    Inventors: Thierry Muller, Emilie Maud Guillaume, Jean-Paul Bombail, Michael Guillodo
  • Patent number: 8817942
    Abstract: The present invention relates to a nuclear reactor, in particular a pool-type nuclear reactor cooled with liquid metal (for example, a heavy metal such as lead or lead-bismuth eutectic) or with sodium or molten salts, having a core formed by a bundle of fuel elements and immersed in a primary fluid circulating between the core and at least one heat exchanger; the fuel elements extend along respective parallel longitudinal axes and have respective bottom active parts immersed in the primary fluid to constitute the core, and respective service parts that extend at the top from the active parts and emerge from the primary fluid; the fuel elements are mechanically supported via respective top end heads anchored to supporting structures and can be operated via handling machines.
    Type: Grant
    Filed: September 25, 2008
    Date of Patent: August 26, 2014
    Assignees: Del Nova Vis S.r.l.
    Inventor: Luciano Cinotti
  • Patent number: 8767902
    Abstract: Nuclear reactor systems and methods are described having many unique features tailored to address the special conditions and needs of emerging markets. The fast neutron spectrum nuclear reactor system may include a reactor having a reactor tank. A reactor core may be located within the reactor tank. The reactor core may include a fuel column of metal or cermet fuel using liquid sodium as a heat transfer medium. A pump may circulate the liquid sodium through a heat exchanger. The system may include a balance of plant with no nuclear safety function. The reactor may be modular, and may produce approximately 100 MWe.
    Type: Grant
    Filed: February 18, 2011
    Date of Patent: July 1, 2014
    Assignee: Advanced Reactor Concepts LLC
    Inventor: Leon C. Walters
  • Patent number: 8638901
    Abstract: A nuclear reactor having a liquid metal or molten salt coolant in a riser space 130?, has a cylindrical containment vessel 134 with a reactor vessel 120?, at least two lobes 121, preferably three to nine lobes 121, each lobe 121 interconnected with the other lobe(s) and each containing a fast reactor core, 116?, 116?, 116? and 116??.
    Type: Grant
    Filed: December 29, 2010
    Date of Patent: January 28, 2014
    Assignee: Westinghouse Electric Company LLC
    Inventors: Edward J. Lahoda, Mario D. Carelli, Matthew J. Memmott
  • Publication number: 20130230605
    Abstract: A suspension of a boron containing compound in the form of crystals, powder or granulate in a solvent which contain a carbomer as dispersant. This suspension is very stable, even at high concentrations, and exhibits favourable non-Newtonian viscosity behavior, which makes it suitable in a number of applications, such as for the control of fission reactions with the generation of electric power from nuclear energy.
    Type: Application
    Filed: July 19, 2011
    Publication date: September 5, 2013
    Applicant: C-IP S.A.
    Inventors: Philippe Ceulemans, Olivier Ceulemans
  • Publication number: 20120288048
    Abstract: A method for controlling a nuclear reactor is disclosed. The method includes providing a moderator zone in a core of the nuclear reactor, providing a fuel in the moderator zone, and providing one or more housings, each having a cavity, adjacent to the fuel. The method also includes allowing movement of a moderator between the moderator zone and the cavity of the one or more housings at a lower portion of the one or more housings. The method further includes confining moderator in the cavity of the one or more housings at an upper portion of the one or more housings.
    Type: Application
    Filed: May 10, 2012
    Publication date: November 15, 2012
    Inventor: Neal Lawrence Mann
  • Publication number: 20090141847
    Abstract: An method for operating a nuclear power generation plant, comprising the steps of: forming a plurality of control rod patterns by operating a plurality of control rods during a first period of one operation cycle of a reactor including said first period before a point of time when all control rods are completely withdrawn from a core of said reactor and a core flow rate reaches firstly a set core flow rate, and a second period after said point of time, controlling stepwise at least once a temperature of feed water supplied to said reactor based on a different set feed water temperature during a period included in said first period for operating said reactor with a formed same control rod pattern, and continuing feed water temperature control based on said set feed water temperature until said core flow rate reaches a set core flow rate set based on said set feed water temperature.
    Type: Application
    Filed: November 28, 2008
    Publication date: June 4, 2009
    Inventors: Tetsushi HINO, Masao CHAKI, Motoo AOYAMA, Takeshi MITSUYASU, Yoshihiko ISHII
  • Patent number: 7447291
    Abstract: A nuclear reactor including: a vessel including at least two parts; a reactor core placed in the vessel and containing fuel rod assemblies; at least one internal structure located within the vessel and having a flange portion sandwiched between the two parts of the vessel; an insertion unit for inserting a neutron-absorbing liquid in the fuel rod assemblies, placed in the vessel; and external control devices placed outside the vessel and connected to the insertion unit through conduits placed inside the internal structure, including the flange portion, wherein the insertion unit comprises a transmission unit partly placed in the conduits.
    Type: Grant
    Filed: February 3, 2004
    Date of Patent: November 4, 2008
    Inventor: Michel Emin
  • Patent number: 6781331
    Abstract: A method and system of regulating an output voltage of a boiling water reactor nuclear reactor plant recirculation system motor generator are provided. The method includes sensing an alternator output voltage and transmitting an alternator output voltage signal to a voltage regulator circuit, sensing an alternator speed and transmitting an alternator speed signal to the voltage regulator circuit, comparing the alternator output voltage signal to the alternator speed signal with a volts per hertz divider network electrically coupled to the alternator output voltage sensing circuit and the alternator speed sensing device, adjusting a capacitive reactance of the voltage regulator with a lead compensation circuit electrically coupled in series with the volts per hertz divider network, and adjusting a current in a control winding of a saturable reactor.
    Type: Grant
    Filed: September 13, 2002
    Date of Patent: August 24, 2004
    Assignee: General Electric Company
    Inventors: James Steven Mokri, Nelso Petroni, William Michael Steiner, Stephen L. Joslin, Craig Ernest Leighty
  • Patent number: 5615239
    Abstract: A core differential pressure and liquid control line apparatus for a nuclear reactor is described. The apparatus includes a first portion configured to be positioned within and extend through an opening in the pressure vessel wall. At least the first tube portion has a diameter less than the diameter of the opening in the pressure vessel wall. An annulus is formed between the exterior surface of the first tube portion and the pressure vessel wall so that a neutron absorbent can be injected into the pressure vessel at the location of the annulus. The apparatus further includes a second L-shaped tube portion configured to be coupled to the first tube portion, and a third tube portion configured to be coupled to the second tube portion. The open end of the third tube portion extends to an elevation above the core plate.
    Type: Grant
    Filed: November 17, 1995
    Date of Patent: March 25, 1997
    Assignee: General Electric Company
    Inventors: Gerald A. Deaver, James W. Pyron, Anh N. Nguyen
  • Patent number: 5291530
    Abstract: A nuclear reactor plant is provided in which the reactor coolant system contains a dissolved solution of enriched boric acid. The boron-10 to boron-11 atomic isotope ratio of the enriched boric acid solution is greater than 19.8:80.2 at the start of the reactor core cycle. The nuclear reactor plant design provides for minimal mixing between the reactor coolant solution containing the enriched boric acid solution and the natural boric acid solution used during refueling operations.
    Type: Grant
    Filed: April 1, 1991
    Date of Patent: March 1, 1994
    Assignee: Westinghouse Electric Corp.
    Inventors: Albert J. Impink, Jr., Joseph A. Battaglia, John W. Fasnacht, George G. Konopka
  • Patent number: 5271052
    Abstract: A nuclear reactor plant is provided in which the reactor coolant system contains a dissolved solution of enriched boric acid. The boron-10 to boron-11 atomic isotope ratio of the enriched boric acid solution is greater than 30:70 at the start of the reactor core cycle. The nuclear reactor plant design provides for minimal mixing between the reactor coolant solution containing the enriched boric acid solution and the natural boric acid solution used during refueling operations.
    Type: Grant
    Filed: January 11, 1993
    Date of Patent: December 14, 1993
    Assignee: Westinghouse Electric Corp.
    Inventors: Albert J. Impink, Jr., Joseph A. Battaglia, John W. Fasnacht, George G. Konopka
  • Patent number: 5265135
    Abstract: An apparatus for providing an inventory of an isotopically enriched acidic solution of an element that is capable of forming a water soluble weakly acidic solution at temperatures amenable to ion exchange and having a lower molecular weight isotope fraction and a higher molecular weight isotope fraction is disclosed. This apparatus includes at least two ion exchangers, each being temperature dependent with respect to their storage capacity of said lower and higher molecular weight isotopes, a hot tank containing a hot tank solution and a cold tank containing a cold tank solution both flow coupled to the ion exchangers. A first series of valves is selectively operable to direct the hot tank solution to one of the ion exchanger and to direct the cold tank solution to the other ion exchangers. A second series of valves is selectively operable to direct the flow from the ion exchangers to either the hot tank or the cold tank. An analyzer for sampling the solution is located upstream from the hot tank.
    Type: Grant
    Filed: October 13, 1992
    Date of Patent: November 23, 1993
    Assignee: Westinghouse Electric Corp.
    Inventors: Albert J. Impink, Jr., Joseph A. Battaglia
  • Patent number: 5227128
    Abstract: A reactor core removable fuel assembly includes upper and lower tie plates having pluralities of fuel rods and hollow control rods extending therebetween. The lower tie plate includes a lower manifold therein joined in flow communication with a reservoir containing a neutron absorbing control liquid, with the reservoir being removable from the reactor core together with the fuel assembly. The control liquid is selectively pumped from the reservoir through the lower manifold and into the control rods for selectively varying the level of the control liquid therein for controlling reactivity.
    Type: Grant
    Filed: August 26, 1992
    Date of Patent: July 13, 1993
    Assignee: General Electric Company
    Inventors: Irvin R. Kobsa, Harold E. Townsend, Russell M. Fawcett
  • Patent number: 5176885
    Abstract: A process and an apparatus are provided which separate the lower molecular weight isotope fraction from the higher molecular weight isotope fraction of an element which forms a water soluble acid at temperatures amenable to ion exchange. The separation is accomplished by shifting the equilibrium constants for absorption and desorption by temperature variations of the acidic solution. The process and apparatus are preferably employed to enrich a boric acid solution in its boron-10 isotope fraction by employing the use of ion exchange resins which are capable of thermally storing and releasing boron isotopes.
    Type: Grant
    Filed: April 1, 1991
    Date of Patent: January 5, 1993
    Assignee: Westinghouse Electric Corporation
    Inventors: Albert J. Impink, Jr., Joseph A. Battaglia
  • Patent number: 5145638
    Abstract: The present invention is directed to a boiling water reactor wherein housed within the reactor pressure vessel is the nuclear core and an upper steam dome connected to a steam outlet in the RPV. The improvement comprises a vessel disposed in the steam dome and containing a neutron poison effective for inactivating the core. This vessel is vented to the steam dome for pressurizng the poison contained therein. The vessel also is connected by a line terminating beneath the core. The line contains an actuatable valve to release the poison through the line upon its actuation. The poison, when released, flows through the line by gravity to beneath the core for mixing with the reactor coolant which passes through the core resulting in consequent inactivation thereof.
    Type: Grant
    Filed: December 20, 1990
    Date of Patent: September 8, 1992
    Assignee: General Electric Company
    Inventor: Willem J. Oosterkamp
  • Patent number: 5139735
    Abstract: A reactivity control system includes a reservoir containing a liquid nuclear poison, at least one stationary, hollow control blade extending vertically into a reactor core, and a poison conduit disposed in flow communication between the reservoir and the control blade for channeling the poison between the reservoir and control blade. The level of the poison in the control blade is controlled for selectively varying nuclear reactivity in the core.
    Type: Grant
    Filed: April 30, 1991
    Date of Patent: August 18, 1992
    Assignee: General Electric Company
    Inventor: Charles W. Dillmann
  • Patent number: 5130078
    Abstract: A method and system for controlling nuclear reactivity in a nuclear reactor are disclosed. The method includes maintaining a nuclear position solution at an initial poison pressure less than the steam pressure within the reactor vessel. The method further includes channeling a pressurizing fluid into the holding tank for pressurizing the poison solution to a pressure greater than the initial pressure thereof, and draining by gravity the poison solution from the holding tank and into the reactor vessel for mixing with the water to reduce reactivity in the core.
    Type: Grant
    Filed: March 11, 1991
    Date of Patent: July 14, 1992
    Assignee: General Electric Company
    Inventor: Charles W. Dillman
  • Patent number: 5112569
    Abstract: An intrinsic-safety nuclear reactor of the pressurized water type, having:a reactor vessel (2) equipped with a core (4), a lower header (5) and an upper header (6), at least one heat exchanger (3) with a secondary fluid, means of hydraulic connection (9, 10) between said headers and said heat exchanger and at least one circulation pump (11),a pressurized container (1) surrounding the reactor vessel (2) and which defines a tank (15) full of a cold, neutron-absorbing liquid;pipes (20) allowing communication between the lower area of said tank and the lower header of the vessel, as well as pipes (21) allowing communication between the upper area of said tank and the upper header,in which the pressure drop in the primary fluid across the core is substantially equal to the difference in head between the cold column of said tank and the hot column of the vessel.The pressurized container (1) is immersed in a pool (18) containing a neutron-absorbing liquid at atmospheric pressure.
    Type: Grant
    Filed: September 15, 1989
    Date of Patent: May 12, 1992
    Assignee: Ansaldo S.p.A.
    Inventor: Luciano Cinotti
  • Patent number: 5091143
    Abstract: The invention is directed to a natural circulation reactor having a reactor pressure vessel with a core housed therein, the core being disposed in such a location that a top portion of the core is submerged under coolant even in the event that any pipe connected to the reactor pressure vessel is broken and then a coolant level in the reactor pressure vessel is lowered due to flushing. This permits the reactor core to be submerged under coolant even in the event of breakage of any pipe connected to the reactor pressure vessel, ensuring to eliminate a possibility that the top portion of the reactor core is exposed temporarily during an intermediate period before actuation of an accumulated coolant injection system to start injecting of the coolant into the reactor pressure vessel after the end of flushing.
    Type: Grant
    Filed: June 9, 1989
    Date of Patent: February 25, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Hitoshi Tate, Fumio Totsuka, Tetuo Horiuchi, Kumiaki Moriya
  • Patent number: 5082618
    Abstract: The method consists in removing the cooling fluid of the primary circuit, and, as a function of the cooling fluid concentration, in passing either all of the cooling fluid into at least one electrodialysis module, or only a part of the cooling fluid into the electrodialysis modules and the other part towards at least one reverse osmosis apparatus, in adding to the cooling fluid, when it leaves the primary circuit, an additive to promote dissociation of the boric acid, and in then returning the cooling fluid into the primary circuit.
    Type: Grant
    Filed: June 13, 1989
    Date of Patent: January 21, 1992
    Assignee: Framatome
    Inventor: Philippe Dagard
  • Patent number: 5008069
    Abstract: A heat-generating member (3), in particular a nuclear reactor core, is placed in a liquid contained in a pressure vessel (1) and adapted to serve as a coolant for the heat-generating member. For cooling of the liquid the pressure vessel is adapted to be included in a circulation system (15a, 15, 14. 16, 16a) for self-circulation of the liquid and/or of steam of the liquid with any contents of uncondensable gas. The circulation system also includes an evaporator (14) arranged in an evaporation pool (13), a supply conduit (15) for conducting liquid and/or steam from a point of connection (15a) in the upper part of the pressure vessel to the evaporator, and a discharge conduit (16) for conducting liquid from the evaporator to a point of connection (16a) on the pressure vessel which is located below the point of connection (15a) for the supply conduit. The evaporator is located at a higher level than the point of connection (16a) on the pressure vessel for the discharge conduit (16).
    Type: Grant
    Filed: February 13, 1990
    Date of Patent: April 16, 1991
    Assignee: ABB Atom AB
    Inventor: Jan Fredell
  • Patent number: 4939754
    Abstract: In a nuclear reactor of the safety type, density locks constitute an important safety function. Two liquid systems can be kept apart by means of density locks. During normal operating conditions, the density locks prevent the warmer water from a primary cooling system from being mixed with the colder water from a secondary cooling system. At an increased temperature level, the density locks permit water to flow through so that the warmer water is mixed with the colder water to reduce the increased temperature level. To prevent an undesired transport through the density locks, for example boric acid leaking in from the secondary cooling system during normal operating conditions, the density locks are provided with a honeycomb consisting of tube pieces assembled in parallel. The honeycomb tube must be much longer than four times the tube diameter. To prevent the occurrence of a resonant interaction between internal waves in the honeycomb tube, the Brunt-Vaisala frequency ##EQU1## must vary through the tubes.
    Type: Grant
    Filed: September 30, 1988
    Date of Patent: July 3, 1990
    Assignee: ABB Atom AB
    Inventors: Hans Ekander, Rikard Gebart
  • Patent number: 4897240
    Abstract: A nuclear reactor includes a reactor vessel, a reactor core disposed within the vessel and including fuel rods, a primary cooling system disposed in the vessel and including a steam generator and a pump and a poison tank disposed within the vessel and containing high concentration boric acid solution. The poison tank surrounds the reactor core, and the steam generator surrounds a portion of the poison tank.
    Type: Grant
    Filed: May 2, 1989
    Date of Patent: January 30, 1990
    Assignee: Japan Atomic Energy Research Institute
    Inventor: Kiyoshi Sako
  • Patent number: 4859406
    Abstract: To be able to design a smaller unit of a nuclear power plant, the containment of pre-stressed concrete has been made in the form of a bottle. In this way, a "conventional" pump with a shaft packing and a dry motor can be used by locating the motor, for driving the pump for circulation of the process water, in a sealed, detachably connected steel dome (16). When being removed, the detachably connected steel dome (16) provides access to the riser (1) for refuelling.
    Type: Grant
    Filed: December 3, 1987
    Date of Patent: August 22, 1989
    Assignee: AB Asea-Atom
    Inventor: K.ang.re Hannerz
  • Patent number: 4818477
    Abstract: A nuclear fuel assembly comprising a plurality of fuel rods, each fuel rod comprising a cladding tube closed at both ends and filled with cylindrical nuclear fuel pellets such as sintered uranium dioxide or uranium plutonium dioxide. All or nearly all of the cylindrical pellets are coated with a refractory boride coating of sufficient thickness to prevent mechanical interaction between the pellets and the tube. The isotopic composition of the boron in the refractory boride is adjusted for each batch of fuel pellets, rods, or assemblage of rods so that the initial excess reactivity, k, of the batch, when assembled in a reactor core, is nearly zero.
    Type: Grant
    Filed: July 10, 1984
    Date of Patent: April 4, 1989
    Assignee: Westinghouse Electric Corp.
    Inventor: Walston Chubb
  • Patent number: 4783306
    Abstract: A pressurized water nuclear reactor has a reactor vessel arranged in a pool, which is filled with a neutron absorbing liquid, for example borated water. The reactor vessel is closed except for tubes connecting it with a tray above it. The coolant in the circuit rises from the vessel to the tray, gives up its heat by flashing, and flows back to the bottom of the vessel, driven by natural circulation. The tray is separated from the pool by a vapor-filled bell, which surrounds it. In the bell the vapor gives up its useful heat to a condenser. The relatively low boron content of the cooling circuit, compared to the pool, is achieved by continuous dilution of the condensate from vapor additionally generated out of the pool water. The dilution process is an equilibrium with continuous inflow of the pool water. The inflow is automatically controlled by the pool level, which rises when the pool water is pressed out from below the bell by overproduction of vapor.
    Type: Grant
    Filed: May 5, 1986
    Date of Patent: November 8, 1988
    Inventors: Georg Vecsey, Pal G. Doroszlai
  • Patent number: 4755352
    Abstract: A system of generating electricity is disclosed. The system employs a new kind of swimming pool type nuclear reactor which is safe and can be made operable unattended but at the same time raises the mean pool temperature by forcing moderator-coolant-shield circulation. When the reactor is combined with an organic Rankine cycle engine, a significant improvement in efficiency of electricity generation can be obtained, making very small nuclear/electricity units economically viable.
    Type: Grant
    Filed: May 15, 1985
    Date of Patent: July 5, 1988
    Assignee: Atomic Energy of Canada Limited
    Inventors: John S. Glen, Henry W. Hinds
  • Patent number: 4735767
    Abstract: A quenching element of the size and shape of a graphite nuclear fuel ball is introduced to the stacked balls of a stacked ball nuclear reactor core to release a neutron absorbing substance upon being heated to a predetermined temperature, thereby controlling the reactivity of the reactor by causing this substance, which may be a gadolinium compound, to deposit upon the graphite surfaces of the fuel element balls.
    Type: Grant
    Filed: August 27, 1986
    Date of Patent: April 5, 1988
    Assignee: Kernforschungsanlage Julich GmbH
    Inventors: Werner Mallener, Theodor Overhoff
  • Patent number: 4693862
    Abstract: A method and apparatus for extending the life of a core of a water moderated nuclear reactor by spectral shift comprising the displacement of a portion of the moderator in the core by a gas having a low neutron cross-section during the initial stage of the life of the core and displacing the gas and replacing it with moderator during the latter part of the life of the core.
    Type: Grant
    Filed: July 2, 1984
    Date of Patent: September 15, 1987
    Assignee: Westinghouse Electric Corp.
    Inventors: Stephen N. Tower, Howard E. Braun, David E. Boyle, Robert B. Salton
  • Patent number: 4683103
    Abstract: A fuel assembly in a nuclear reactor has a spectral shift apparatus including a plurality of displacer rods for controlling reactivity in the assembly and an apparatus for refurbishing the displacer rods for reuse. Each displacer rod contains a quantity of water equivalent to a small fraction of the rod volume. Also, the spectral shift apparatus includes a manifold with a central plenum and a rupturable disk connected to the manifold. The manifold is connected in flow communication with the displacer rods. The disk which seals the displacer rods as well as the manifold plenum is rupturable at a given pressure differential thereacross so as to allow entry of the moderator/coolant liquid into the manifold and rods. Also, a screen adjacent the disk restricts it to rupturing in one direction only.
    Type: Grant
    Filed: February 12, 1985
    Date of Patent: July 28, 1987
    Assignee: Westinghouse Electric Corp.
    Inventors: Randy G. Lott, Frank J. Baloh
  • Patent number: 4664878
    Abstract: A non-boron moderator filled rod for a nuclear reactor fuel assembly has a tubular body with a pair of end plugs sealing the opposite ends thereof and defining a chamber within the body. A liquid moderator, such as light water, is contained witin the chamber. One of the end plugs acts as a hydride sink and a hydrogen getter sponge material is disposed adjacent the other end plug.
    Type: Grant
    Filed: September 26, 1984
    Date of Patent: May 12, 1987
    Assignee: Westinghouse Electric Corp.
    Inventors: John F. Wilson, Pratap K. Doshi, Samuel Cerni
  • Patent number: 4661306
    Abstract: Apparatus is disclosed for introducing a low neutron moderating fluid into the reactor vessel of a spectral shift pressurized water nuclear reactor and for distributing the moderating fluid through the lower core support plate into the fuel assemblies in the core.
    Type: Grant
    Filed: July 2, 1984
    Date of Patent: April 28, 1987
    Assignee: Westinghouse Electric Corp.
    Inventors: Howard F. Fensterer, William E. Klassen, Luciano Veronesi, David E. Boyle, Robert B. Salton
  • Patent number: 4657726
    Abstract: A moderator control apparatus is provided for use with a fuel assembly to improve fuel utilization in thereby reducing fuel cycle costs. The apparatus includes a plurality of displacer rods filled with a burnable poison gas which are inserted into the guide thimbles of the fuel assembly to displace a portion of the coolant in thus reducing the H/U ratio at the start of the cycle. The displacer rods are connected at their upper ends to a manifold which has a central opening with a plurality of inlet ports disposed about the central opening and in fluid flow communication with the rods. A rotatable valve is disposed in the central opening and operable to selectively open and close the inlet ports so as to either permit or obstruct the flow of coolant into the displacer rods in a predetermined controlled manner.
    Type: Grant
    Filed: June 22, 1984
    Date of Patent: April 14, 1987
    Assignee: Westinghouse Electric Corp.
    Inventors: Dale B. Lancaster, Edmund E. DeMario
  • Patent number: 4640813
    Abstract: A soluble burnable absorber rod for a nuclear reactor fuel assembly has a tubular body with a pair of end plugs sealing the opposite ends thereof and defining a chamber within the body. A neutron absorber material in liquid form, preferably boric acid with an enhanced concentration of boron isotope B-10, is contained within the chamber. The tubular body has reinforcing convolutions formed therein for strengthening the body to withstand external pressure acting thereon. Also, one of the end plugs acts as a hydride sink and a hydrogen getter material is disposed adjacent the other end plug.
    Type: Grant
    Filed: September 26, 1984
    Date of Patent: February 3, 1987
    Assignee: Westinghouse Electric Corp.
    Inventors: Pratap K. Doshi, John F. Wilson
  • Patent number: 4526742
    Abstract: A pressurized water nuclear reactor comprises a reactor vessel arranged in a pool made in the form of a pressure vessel, the pool being filled with a strongly neutron-absorbing liquid, for example borated water. The reactor vessel, in addition to being connected to a primary system, is provided with a lower shutdown opening, arranged below the reactor core, for pool liquid and with an upper shutdown opening, arranged above the core, for pool liquid.
    Type: Grant
    Filed: March 25, 1982
    Date of Patent: July 2, 1985
    Assignee: AB Asea-Atom
    Inventor: Kare Hannerz
  • Patent number: 4495140
    Abstract: A gas cooled nuclear reactor is permanently deactivated on occurrence of an emergency by pyrolytic deposition of boron or refractory or stable compounds of boron in the fluid channels of the fuel elements of the reactor. The boron is enriched in boron 10. The deposition takes place in so short a time interval as to preclude a major catastrophe by reason of penetration of water into the reactor. Carbon and/or nitrogen-containing boron compounds are injected directly into the reactor or compounds generated by reaction in the working fluid of the reactor between diborane and other boron hydrides with unsaturated compounds, such as acetylene and ammonia flow through the reactor. The compounds are carried by the working fluid through the core and are pyrolized in the heat of the core to produce more stable boron, or boron-carbon and boron-nitrogen compounds or metal borides which adhere to the walls of the channels in the fuel elements, deactivating the core.
    Type: Grant
    Filed: November 24, 1981
    Date of Patent: January 22, 1985
    Assignee: Westinghouse Electric Corp.
    Inventors: Edgar L. Kochka, Joseph M. Tobin, deceased, Arlene F. Neve, administratrix
  • Patent number: 4462956
    Abstract: Apparatus for partitioning off the core of a nuclear reactor constituted by a set of boxes (8, 9, 10, 11) each comprising at least two plates (12-13, 14-15, 27-29, 28-30) rigidly assembled at right angles and disposed in the longitudinal direction of the assemblies, and a plurality of transverse plates (32) perpendicular to the longitudinal plates. The boxes are removably disposed side by side inside the core casing (1), and bearing thereon. The faces of the longitudinal plates directed towards the reactor core serve as bearing faces for the assemblies. Each of the boxes is fixed to at least one of the upper or lower plates of the core by a flexible coupling allowing longitudinal displacement.
    Type: Grant
    Filed: April 8, 1981
    Date of Patent: July 31, 1984
    Assignee: Framatome
    Inventors: Pierre Boiron, Pierre Poitrenaud
  • Patent number: 4435184
    Abstract: A waste-water concentrate containing boric acid together with chemical residues and radionuclides, especially from a nuclear power plant, is treated to recovering boric acid which can be recycled to the plant. According to the invention, the practically neutral solution is acidified with an acid selected from the group which consists of sulfuric acid, hydrochloric acid, nitric acid and acetic acid to precipitate the boric acid which is separated from the concentrate and subjected to at least one recrystallization step. The boric acid thus obtained is of comparatively high purity.
    Type: Grant
    Filed: April 30, 1981
    Date of Patent: March 6, 1984
    Assignee: Rheinisch-Westfalisches Elektrizitatswerk AG
    Inventors: Heinrich J. Schroeder, Rainer Ambros, Gottfried Paffrath, Norbert Brenner
  • Patent number: 4299657
    Abstract: In a process for running a nuclear reactor cooled with light water, by displacing control rods and modifying the physical and/or chemical state of the coolant, the value of the running parameters of the reactor are continuously measured and recorded and the parameters describing the state of the reactor core are calculated for each substantial modification of the running parameters. The parameters describing the state of the core are measured at defined intervals of time and the calculated parameters are replaced by the measure parameters. The modified parameters resulting from predetermined sequences of action taken on the control rods or the coolant, and the action which must be taken on the running parameters in order to comply with a given program, are calculated by way of predictions. Action is taken on the control rods and the coolant in accordance with the results of the calculation.
    Type: Grant
    Filed: October 3, 1979
    Date of Patent: November 10, 1981
    Assignee: Framatome
    Inventors: Georges Abenhaim, Gerard Francillon