Abstract: In one aspect, non-invasive methods are described in which combinations of certain battery parameter values are used to identify whether metal plating (e.g., lithium plating) has occurred during charging of a battery. In response to the detection of metal plating and/or conditions associated with metal plating, one or more characteristics of a charge process may be adjusted or adapted to maintain battery parameter values within a specified range. In some cases, after detection of metal plating, a battery charge process may be adjusted or adapted to remove metal plating from a battery's anode by a discharge pulse.

Abstract: An igniter apparatus which generates a high speed buoyancy induced vortex to funnel hydrogen and air from the surrounding onto the “igniter core” where an “igniter core” heats up to the auto ignition temperature by the exothermic catalytic oxidation of hydrogen on its surface. Water (vapor) is formed as the product, which inhibits the oxidation reaction, if not stripped away from the catalyst surface. The high velocity of the vortex ensures the stripping of the boundary layer of steam that is formed by the reaction, thus ensuring more active sites are available for hydrogen oxidation. The vortex is formed by channeling an upward draft into a vortex by guided fins. The upward draft is formed by a plate, which is also coated with a hydrogen recombination catalyst. The plate becomes hot by the same catalytic oxidation reaction in the presence of air containing hydrogen.

Abstract: This disclosure describes various configurations and components of a molten fuel fast or thermal nuclear reactor for managing the operating temperature in the reactor core. The disclosure includes various configurations of direct reactor auxiliary cooling system (DRACS) heat exchangers and primary heat exchangers as well as descriptions of improved flow paths for nuclear fuel, primary coolant and DRACS coolant through the reactor components.

Abstract: A method and system for collecting xenon (Xe) is described. A microchannel heat exchanger is used in combination with a mechanical cooler and an absorbent. A combination of components makes up a Xe Collection Subsystem that is adapted for use in an efficient process for collecting, purifying, and measuring Xe isotopes collected from air as part of the International Monitoring System.

Abstract: A method and system for collecting xenon (Xe) is described. A microchannel heat exchanger is used in combination with a mechanical cooler and an absorbent. A combination of components makes up a Xe Collection Subsystem that is adapted for use in an efficient process for collecting, purifying, and measuring Xe isotopes collected from air as part of the International Monitoring System.

Abstract: According to an embodiment, a nuclear reactor containment vessel has: a primary reactor containment vessel which contains a nuclear pressure vessel; a secondary reactor containment vessel and which is disposed outside the primary reactor containment vessel which has the pressure resistant properties and the leak-tightness which are equivalent to those of the primary reactor containment vessel; an air bag which is disposed within the secondary reactor containment vessel and which, when a failure occurs in primary reactor containment vessel, expands while receiving and encapsulating a high pressure gas discharged from the inside of the primary reactor containment vessel; and a gas phase vent pipe which connects the primary reactor containment vessel and the air bag.

Abstract: A sampling system for taking a sample from the atmosphere in a reactor containment of a nuclear plant, includes a sampling line which is connected to a vacuum system and to an analysis system. The sampling line opens into the reactor containment and has a restriction device connected upstream thereof on the gas side for connection to the atmosphere in the reactor containment. A method for taking such a sample is also provided.

Abstract: A method for underwater packaging of radioactive materials includes creating a vacuum in a cavity of a cleaning device to automatically cause a portion of the cleaning device to move upward to actuate the cleaning device from an open position to a closed position; mounting the cleaning device inside a safe containment area of a transportation and/or storage device; placing the transportation and/or storage device in a pool after filling the safe containment area with water; loading a radioactive material into the safe containment area; closing the transportation and/or storage device using at least one cover; extracting the transportation and/or storage device from the pool; draining the water inside the safe containment area; and creating a pressure differential in the safe containment area to dry the safe containment area, wherein the pressure differential causes the cleaning device to automatically actuate from the closed position to the open position.

Abstract: The invention relates to a recombiner system (1) for catalytically recombining hydrogen that is produced in energy accumulators or energy converters. The aim of the invention is to provide a recombiner system (1) which can optionally be used for energy accumulator or energy converter systems having different operating conditions and that helps to counteract functional defects. For this purpose, the recombiner system (1) is formed by individual recombiner elements (2) that can be combined with each other in a modular fashion, said recombiner elements (2) comprising at least one respective catalyst (12).

Abstract: A hydrogen combustion system comprising: an external cylinder 1 constituting the exterior of a double tube construction; an internal cylinder 2 formed by a porous metal plate constituting the interior of said double tube construction; hydrogen combustion catalyst 4 supported with precious metals on spherical ceramic support surface, formed in pellet state, being packed in said internal cylinder 2; an insert pipe 3 formed by porous metal plate inserted in the center of said internal cylinder 2; pre-heating heaters 5 installed between said insert pipe 3 and said internal cylinder 2 to preheat said hydrogen combustion catalyst 4 to ambient atmosphere of over catalytic reaction temperatures; a hydrogen introducing port 8 connecting to said insert pipe 3; an air introducing port 9 provided at the bottom of said external cylinder 1 in the area between said external cylinder 1 and said internal cylinder 2, wherein air for hydrogen combustion is introduced by the drift effect resulting from the differential pressure

Abstract: A safe, reduced pressure apparatus for generating water vapor from hydrogen and oxygen and feeding high purity moisture to processes such as semiconductor production. The apparatus eliminates the possibility of the gas igniting by maintaining the internal pressure of the catalytic reactor for generating moisture at a high level while supplying moisture gas from the reactor under reduced pressure. A heat dissipation reactor improvement substantially increases moisture generation without being an enlargement in size by efficient cooling of the reactor alumite-treated fins.

Abstract: In a method for catalytic oxidation of a gas, the outlay required is kept at a low level for reliably treating even relatively large quantities of gas and/or high concentrations of the gas fraction that needs to be treated. For this purpose, a gas stream including the gas being treated is circulated through a reaction zone and a return-flow zone, which is in communication with the inlet and outlet sides of the reaction zone. The circulation of the gas stream can be maintained effectively in the form of a passive system if the gas stream which includes the gas to be treated is guided in the upward direction in the reaction zone and the upward flow is assisted by convection resulting from the heat released during the oxidation reaction. Furthermore, the gas stream is preferably cooled locally in the return-flow zone by spray cooling.

Abstract: The invention relates to a catalyst element for a recombinator for eliminating hydrogen from accident atmospheres, in which the technical problem of continuously efficiently converting both small and large amounts of hydrogen with the atmospheric air-oxygen present in the safety containers within a broad concentration range, and routing away the reaction heat arising in the process to such an extent that the respective ignition temperature is not reached in the present mixture is resolved by having the catalyst element exhibit a flat basic body (2), which is arranged within the area of flow through the recombinator, wherein the surface of the basic body (2) over which the accident atmosphere flows has a varying coverage density with catalyst material (3).

Abstract: A process for the treatment of radioactive graphite which includes the following steps: (i) reacting the radioactive graphite at a temperature in the range of from 250° C. to 900° C. with superheated steam or gases containing water vapor to form hydrogen and carbon monoxide; (ii) reacting the hydrogen and carbon monoxide from step (i) to form water and carbon dioxide; and (iii) reacting the carbon dioxide of step (ii) with metal oxides to for carbonate salts. The process enables radioactive graphite, such as graphite moderator, to be treated either in-situ or externally of a decommissioned nuclear reactor.

Abstract: A hydrogen/oxygen reaction is initiated in a catalytic recombination or ignition device. The device has one or more catalyst bodies with a predetermined catalytic surface. Only a small portion of the entire available catalytic surface, preferably less than 5% of the surface, is permanently maintained at a temperature level above ambient temperature. The temperature is raised by introducing energy with a heater. The heated surface portion acts as an initial igniter.

Abstract: An ignition system has a plurality of spark igniters for the recombination of hydrogen in a gas mixture. The ignition system provides and ensures reliable early ignition of an ignitable gas mixture, even in the case of comparatively fast gas displacement. Each spark igniter is, according to the invention, configured as a high-speed igniter with an operating frequency in excess of about 10 Hz. In order to ensure reliable ignition of the ignitable gas mixture both in the event of a temporary failure of external units, and when the ignition system has a particularly long operating time, the spark igniters are advantageously connected together in groups for supplying them with energy. Each group of spark igniters is connected to an intermediate energy store common to them, and the intermediate energy stores are connected to a central energy supply unit.

Abstract: An apparatus for the recombination of hydrogen in a gas mixture, in particular for a nuclear power station, during the operation of which unintentional ignition of the gas mixture is avoided in a particularly reliable way. The apparatus contains a catalyst configuration that is disposed in a housing through which the gas mixture can flow by free convection in the operating situation and the catalyst configuration is assigned a flame retention device. In this case, a sediment trap is preferably integrated into the flame retention device, so that hot catalyst particles that become detached from the catalyst configuration are reliably prevented from flowing out counter to the direction of flow of the gas mixture.

Abstract: In order to determine a concentration of a gas mixture, especially a hydrogen concentration of a containment atmosphere of a nuclear power station, a temperature change resulting from a catalytic reaction is measured. The gas mixture is diluted with a motive gas of known composition. The dilution is carried out by a jet pump.

Abstract: A containment of a nuclear power station includes a device for igniting hydrogen contained in a hydrogen/air mixture. A central electrode for lightning flash generation is provided to ensure the maintenance of a particularly low hydrogen concentration in the entire interior of the containment. The central electrode is connected to a high-voltage source for generating a high voltage greater than the disruptive discharge voltage of air.

Abstract: An apparatus for controlling dissolved oxygen concentration in primary and secondary cooling water in boiling water and pressurized water atomic reactors is disclosed. The apparatus contains an electrolytic cell having an anode chamber and a cathode chamber separated from one another by a diaphragm of a solid polymer electrolyte membrane. The diaphragm contains: (a) an ion exchange membrane and (b) a pair of multilayered electrodes chemically plated to both surfaces of the ion exchange membrane. The electrolytic cell is operatively connected to a circular route for cooling water in the reactor, and hydrogen gas generated through electrolysis of deionized water in the cathode side of the cell is introduced into the circular route for the cooling water to control the dissolved oxygen concentration of the cooling water.

Abstract: A device for passively inerting the gas mixture forming in the reactor containment of a nuclear power plant in an accident situation is proposed, which device is based on the use of chemical substances which react or disintegrate, releasing an inerting gas or gas mixture when a certain temperature of reaction is reached. This device is especially suitable for use in connection with catalytic recombiners for removing hydrogen through oxidation with the oxygen present. The heat resulting from this exothermic process of recombination can be put to use for heating up chemical substances to the required temperature, these having temperatures of reaction that lie above the temperature (approximately 100.degree. C.) that develops in the reactor containment in an accident situation.

Abstract: A gas injection system of a nuclear power plant including a reactor and a gaseous waste disposal system, comprises a hydrogen injection unit for injecting hydrogen into a reactor of a nuclear power plant, an oxygen injection unit for injecting oxygen into a gaseous waste disposal system in which the oxygen is recombined with the hydrogen passed by way of the reactor, a densitometer for measuring a balance of concentration between the hydrogen and the oxygen in the gaseous waste disposal system, a flowmeter for measuring a flow rate of an exhaust gas of the gaseous waste disposal system, and a controlling unit for controlling the quantities of the hydrogen gas and the oxygen gas.

Abstract: To ensure safe removal of flammable explosive gaseous mixtures, the flammable mixtures are burned and/or recombined in partial volumes of the container separated from the rest of the container by metal grilles (18,19). The combustion is thereby prevented from spreading by the principle of the Davy safety lamp. The combustion and/or recombination in the partial volumes is effected by means of ignition sources (20), such as electric sparks, hot surfaces, open flames and/or catalytic surfaces. The heat energy released during combustion is transferred by means of cooling devices such as heat pipes. The temperature of the grille is sued to control the energy supply of the ignition source(s) and should never exceed approximately 2/3 of the ignition temperature of the flammable gaseous mixture; when the temperature reaches 3/4 of the ignition temperature, a fuse cuts off the energy supply. If the grille suffers mechanical damage, it touches an electrically insulated internal grille.

Abstract: An apparatus for removing hydrogen from a mixture of gases containing hydrogen, oxygen, steam, and aerosols, with a catalyst arrangement composed of a substrate coated with a material which catalyzes the oxidation of hydrogen while releasing heat. The apparatus is characterized by a protective device which encloses a catalyst arrangement until a preset temperature is reached. Once the preset temperature is reached, the apparatus is automatically movable into a position which exposes the catalyst arrangement, with the protective device being permeable to gas pressure but essentially impermeable to aerosols. Consequently, the catalyst arrangement is protected against deposition of aerosols contained in the gas mixture until the preset temperature is reached.

Abstract: A device for controlled combustion of an ignitable hydrogen/air mixture in a gas mixture of a nuclear power plant, especially in a containment thereof, includes a spark igniter for tripping an ignition process. At least one ignition source is connected to the spark igniter. The ignition source has a self-sufficient energy storage device. The ignition source has at least one first trip element connected between the spark igniter and the energy storage device for responding as a function of temperature to trip the ignition process, and at least one second trip element connected between the spark igniter and the energy storage device for responding as a function of pressure to trip the ignition process. The at least one first trip element is in thermally conductive contact and the at least one second trip element is in pressure-transmitting contact with the gas mixture to be monitored. The energy storage device discharges to the spark igniter if one of the trip elements responds.

Abstract: Method and apparatus for avoiding potential accidents in water-cooled nuclear reactors of the type having an enclosing containment, due to the formation of an explosive gas mixture in the containment. Air is withdrawn from the containment and fed to at least one internal combustion engine as combustion air for the engine. The exhaust gases created by the internal combustion engine are then recycled back into the containment. The result is the lowering of the oxygen partial pressure in the containment to below the critical limit for oxyhydrogen explosion.

Abstract: A method of avoiding localized hydrogen build-ups in the atmospheres of safety tanks of reactors, especially light water reactors, is provided. After a break down that is accompanied by loss of coolant has occurred, the cooling water temperature in the sump of the safety tank is adjusted in the phase of the long term cooling to a temperature that is high than the air temperature in the dome of the safety tank, with this temperature adjustment being effected in such a way that an adequate intermixing of the atmosphere in said safety tank is effective in a convective manner.

Abstract: An apparatus for the controlled combustion of ignitable hydrogen-air mixtures in the containment of water-cooled nuclear reactor plants includes at least one ignition source having a self-sufficient energy reservoir with a charge status being monitorable at regular time intervals. A tripping element of the ignition source responds as a function of temperature for tripping an ignition process and triggering a discharge of the energy reservoir in the ignition source during a predetermined period of time.

Abstract: Process and apparatus for heating a gaseous mixture from a nuclear reactor containing hydrogen and air to its ignition temperature to convert hydrogen to water vapor and then cooling the resultant gaseous mixture after heating to a temperature below its ignition temperature prior to discharging the resultant gaseous mixture from the apparatus.

Abstract: A process for the controlled discharge from a reactor containment structure of a gas cooled nuclear power plant and the installation for achieving this process include parallel discharge circuits from a reactor containment structure to a discharge stack. The flow of discharge from the reactor containment structure normally flows in a primary discharge circuit and may be directed wholly or partially to the parallel secondary discharge circuit. The secondary discharge circuit contains means for reduction of the temperature of the discharge, means for deposition of particulate fission products and they also contain means for recombination of combustible gases and means for filtration of the discharge. Nuclear power plant installations and processes for controlling the discharge from a reactor containment structure in this fashion permit safe discharge of naturally occurring leakage for gas cooled nuclear reactors, as well as leakage occurring in the event of reactor failure.

Abstract: A method and an apparatus for avoiding or reducing the interactions and their consequences from contact of hot liquid metals with concrete. At least for the region of the concrete structure near the surfaces which may come into contact with the hot liquid metal, there is employed a concrete containing aluminum oxide, magnesium oxide, zirconium oxide, or a mixture thereof, in a proportion of 70% by weight to 96.5% by weight.

Abstract: Nuclear power station, including a containment for enclosing activity-carrying components having a given height and upper and lower parts, pipelines being extended in vertical direction in the containment over at least half of the given height thereof from the upper part to the lower part of the containment for mixing a gas atmosphere in the containment, the pipelines having an open top and bottom and an outlet in the lower part of the containment, a transporting device for mixing the gas atmosphere in the containment in the form of a blower connected in the pipelines for transporting gas from the upper part to the lower part of the containment in the pipelines, and a recombination device connected downstream of the blower in the pipelines for shunting the outlets thereof in the lower part and for targeted oxidation of free hydrogen within the containment.

Abstract: In a method of inhibiting or avoiding intermixing of the atmosphere which exists in a closed nuclear reactor containment space with a gaseous substance present in the same space a change in density of the atmosphere is induced in either lower or upper area of the space such that a stable atmosphere stratified into superimposed layers is formed in that space due to the change in density.

Abstract: A hydrogen removal system (10) separates hydrogen from the containment atmosphere of a nuclear power plant using a hydrogen permeable membrane separator (30). Water vapor is removed by condenser (14) from a gas stream withdrawn from the containment atmosphere. The gas stream is then compressed by compressor (24) and cooled (28,34) to the operating temperature of the hydrogen permeable membrane separator (30). The separator (30) separates the gas stream into a first stream, rich in hydrogen permeate, and a second stream that is hydrogen depleted. The separated hydrogen is passed through a charcoal adsorber (48) to adsorb radioactive particles that have passed through the hydrogen permeable membrane (44). The hydrogen is then flared in gas burner (52) with atmospheric air and the combustion products vented to the plant vent. The hydrogen depleted stream is returned to containment through a regenerative heat exchanger (28) and expander (60).

Abstract: In a method for the controlled removal of hydrogen released into the chambers of a nuclear reactor containment after a break of the primary cooling system, the hydrogen is contacted with an oxygen providing material stored in the containment which causes recombination of the hydrogen to H.sub.2 O in a controlled manner at least until the amount of the gas within the hydrogen chamber is below the ignition limit of a hydrogen oxygen gas mixture.

Abstract: A flame arrestor is disclosed which includes a conduit extending along inside of a drum arranged to contain a quantity of non-combustible liquid. This conduit is equipped with bubbler nozzles that discharge a combustible gas into the liquid in the form of separate, discrete bubbles. The gas is drawn from the drum through outlets above the liquid level and deflectors are positioned to deflect and distribute a flame front entering the drum through any of the nozzles.