Abstract: A fuel system for a power generator using hydrogen fuel and a method of recovering a safety marker added to the hydrogen fuel. The hydrogen fuel may be stored in a tank and delivered, in at least one of a gaseous phase and a supercritical phase, to a power generator. The hydrogen fuel is delivered with a fuel delivery assembly and contains at least one safety marker when the fuel is in the fuel delivery assembly. The at least one safety marker is separated from the hydrogen fuel, using, for example, a separator. The at least one safety marker separated from the hydrogen fuel is stored in a safety marker storage tank. The safety marker may be a visual safety marker, such as a noble gas, or an odorant.

Abstract: A nuclear plant has a containment shell and a pressure relief line passing out of the containment shell and sealed by a shut-off valve, and through which a pressure relief flow can flow during relief operation, such that it is configured for particularly reliable management of critical scenarios where there is a considerable pressure increase within the containment shell at the same time as the release of hydrogen and/or carbon monoxide. A gas flow treatment device is provided upstream from the respective pressure relief line, and contains a flow duct and has a lower inflow opening and an upper inflow/outflow opening. Catalytic elements for eliminating hydrogen and/or carbon monoxide are arranged in the flow duct above the lower inflow opening. During a critical fault, the flow duct is flowed through from bottom to top by a gas mixture present in the containment shell by the principle of natural convection.

Abstract: A flexible filter retainer and a holding frame assembly having a flexible retainer are provided. In one embodiment, the flexible filter retainer for the holding frame comprises a flat body extending from a first end to a second end. The body comprises a bowed shaped retaining portion disposed at the first end and comprises a first strip and a top face. The body also comprises a fixed portion disposed at the second end and comprises a second strip. The first and second strips are linearly aligned and laterally offset from the top face. In another embodiment, a filter holding frame assembly comprises a holding frame and flexible filter retainers coupled to the holding frame. Each retainer comprises a flat body extending from a first end to a second end. The body comprises a retaining portion disposed at the first end and a fixed portion disposed at the second end.

Abstract: A system (100) for controlling the environment in a reaction box (300) comprises a controller (150) configured to control a gas multiplexer (130) to switch between applying an under pressure in the reaction box (300) from a vacuum pump (140) and applying a gas flow from a connected gas source (200) to the reaction box (300) multiple times in a cyclic manner. A particle monitor (160) generates particle information representing a concentration of particles in the reaction box (300). This particle information is stored as a GMP clean room classification notification for the reaction box (300).

Abstract: A ventilation system operating method for a service personnel-accessible operations room or control room in a nuclear plant or nuclear power plant enables a supply of decontaminated fresh air at least for a few hours in the event of serious incidents involving the release of radioactive activity. The content of radioactive inert gases in the fresh air supplied to the operations room should be as low as possible. Therefore, an air supply line is guided from an external inlet to the operations room, a first fan and a first inert gas adsorber column are connected into the air supply line, an air discharge line is guided from the operations room to an external outlet, a second fan and a second inert gas adsorber column are connected into the air discharge line, and a switchover device interchanges the roles of the first and second inert gas adsorber columns.

Abstract: An adsorbing substance made of a material having an acid center in its molecular frame is installed in a passage for steam generated in a reactor pressure vessel 1. The adsorbing substance adsorbs and holds N-16 compound for decay. Therefore, the amount of N-16 entering into a turbine system is decreased and dose in the turbine system can be reduced.

Abstract: The present invention relates to a passive filtration system for a fuel handling area having a spent fuel pool in a nuclear reactor. The passive filtration system reduces a discharge into the atmosphere of particulates, such as radioactive particulates, generated in a spent fuel pool boiling event. The passive filtration system includes a discharge path, a vent mechanism positioned between the fuel handling area and the discharge path. The vent mechanism is structured to release a steam and air mixture from the fuel handling area to the discharge path. The steam and air mixture includes the particulates. The passive filtration system further includes an air filtration unit located in the discharge path and this unit has at least one passive filter. The steam and air mixture is forced through the at least one passive filter due to a differential pressure generated in the fuel handling area.

Abstract: A method and a device depressurize a nuclear power plant. A depressurization flow is conducted out of a containment shell into the atmosphere via a depressurization line having a filter system. The filter system contains a filter chamber having an inlet, an outlet, and a sorbent filter. The depressurization flow is first conducted in a high-pressure section, then is depressurized by expansion at a throttle device, then conducted through the filter chamber having the sorbent filter, and finally blown out. To enable an effective retention of activity carriers contained in the depressurization flow, including organic compounds containing iodine, the depressurization flow depressurized by the throttle device is conducted through a superheating section before the depressurization flow enters the filter chamber, in which superheating section the depressurization flow is heated from the not yet depressurized depressurization flow to a temperature that is at least 10° C. above the dew point temperature.

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 wet filter for a nuclear reactor primary containment vent that employs an inclined manifold having a plurality of outlets that communicate through a first set of metal fiber filters submerged in a pool of water enclosed within a pressure vessel. A demister suspended above the pool of water to remove any entrained moisture in the filtered effluent before being passed through a second stage of higher density, dry, metal fiber filters connected to a second manifold that communicates with an outlet on the pressure vessel that is connected to an exhaust passage to the atmosphere.

Abstract: A method for extracting tritium from irradiated boiling water reactor control rods that have cruciform-shaped. Bands of a malleable metal are wrapped around the flat portions of the blades, one band near the top of each blade panel and a second band near the bottom. The bands are crimped and an inlet penetration is formed through one of the bands and the panel and an outlet penetration is formed through the second band and the panel. A termination of each end of a closed loop conduit is sealably connected to the inlet and outlet for transporting a carrier gas through the interior of the panel. The carrier gas passing through the interior transports the tritium out of the panel to a tritium getter filter to capture the tritium. The carrier gas then recirculates through the system.

Abstract: A method and a device depressurize a nuclear power plant. A depressurization flow is conducted out of a containment shell into the atmosphere via a depressurization line having a filter system. The filter system contains a filter chamber having an inlet, an outlet, and a sorbent filter. The depressurization flow is first conducted in a high-pressure section, then is depressurized by expansion at a throttle device, then conducted through the filter chamber having the sorbent filter, and finally blown out. To enable an effective retention of activity carriers contained in the depressurization flow, including organic compounds containing iodine, the depressurization flow depressurized by the throttle device is conducted through a superheating section before the depressurization flow enters the filter chamber, in which superheating section the depressurization flow is heated from the not yet depressurized depressurization flow to a temperature that is at least 10 ° C. above the dew point temperature.

Abstract: This invention relates to a nuclear plant having a reactor vessel and a fluid circuit including flow path defining means, defining a flow path for circulating a reactor coolant fluid from and to the reactor vessel. The nuclear plant includes a particle collection zone defined along at least part of the length of the flow path, and particle deflection means arranged in particle deflecting relationship with the flow path to deflect particles from a fluid stream in the flow path into or toward the particle collection zone.

Abstract: A nuclear installation has a reactor containment which is connected to a pressure relief line. A Venturi scrubber, which is arranged in a vessel containing a washing liquid, and a throttle device are connected in series in the pressure relief line. The novel system restrains, with particularly high reliability, fine air-transported activities or aerosols during decompression such that release thereof into the environment is practically impossible. The Venturi scrubber and the throttle device are dimensioned in such a way that, in the case of a critical drop in pressure of an air-vapor mixture flowing in the decompression line, a flow speed of said air-vapor mixture of more than 150 m/s, preferably more than 200 m/s, can be adjusted with respect to the throttle device in the Venturi scrubber.

Abstract: In the boiling water nuclear plant of the present invention, a steam dryer is disposed in a reactor pressure vessel. Materials that have capability of capturing nitrogen compounds containing N-16 are supported on porous member. The porous members are placed in a region where steam goes through in the steam dryer. For example, both or either of perforated plates installed in the steam dryer is constituted of the porous member on which N-16 capture material is supported. When steam containing N-16 goes through the perforated plates, the N-16 is captured by the porous member, whereby the N-16 transfer amount into the turbine system is reduced.

Abstract: In a chemical decontamination apparatus, a catalyst decomposition column in an upstream side of an ion exchange resin column and a hydrogen peroxide injection apparatus in a further upstream side, reduce the amount of waste products caused by a chemical decontaminating agent where a mixed decontaminating agent for a composition trapped in a cation resin column and for a composition trapped in an anion exchange resin are used for the chemical decontaminating agent, selectively decompose the composition trapped in the cation resin column in an inlet side of a cleaning apparatus when radioactive nuclides in the decontaminating agent are cleansed using the cation resin column during decontamination, and decompose both compositions after completion of the decontamination. The chemical decontamination thus selectively decomposes the chemical decontaminating agent, which is a component of the load to the cation resin column.

Abstract: Inert gaseous fission products, including beryllium, rubidium, and krypton isotopes, resulting from the operation of a uranyl sulfate water solution nuclear reactor are passed through a delaying device to precipitate out strontium-90, then passed to a second delaying device to precipitate out the desired strontium-89.

Abstract: Radioactive stents used in angioplasty on sclerotic coronary arteries without the risk of restenosis can be produced by ion injecting 133Xe into the surfaces of stents as a nuclide that has a shorter half-life and emits a smaller maximum energy of &bgr;-rays than 32p Uniform ion injection is accomplished using an apparatus capable of uniform irradiation of the stents with 133Xe ion beams. The source of 133Xe is a nuclear fission product generated from 235U in the fuel rods in nuclear reactor.

Abstract: A containment, such as a glovebox (4), has an air extract system comprising suction means which extracts air from the containment through a vortex amplifier (1) mounted in a containment wall opening (2). The amplifier (1) serves to control the extent of suction extracted from the containment. Air exiting from the amplifier is drawn through a filter (32) removably arranged within a filter tube (31), which extends substantially parallel to the containment wall (3). A transfer passage (29), having a cross-sectional area less than that of the wall opening (2), provides a communication between an outlet side of the amplifier (1) and the filter tube (31). At least an initial portion of the transfer passage (29) extends perpendicularly to the wall. The filter tube (31) has open ends normally closed by covers (40, 41). Removal of the covers (40, 41) enables a clean filter to be installed in the filter tube while ejecting the used filter.

Abstract: When hydrogen is generated within the containment of a nuclear power station, its containment atmosphere must be inerted. An undesired pressure buildup within the containment is prevented during such inerting with the apparatus and the method. It is possible to vent and inert the containment atmosphere simultaneously. A reversible activity holdup device is provided, which makes it possible to vent the containment atmosphere, without radioactive material being released into the surroundings. It is thereby also possible for the containment of a nuclear power station to be inerted even as a preventive measure, so that the safety of the nuclear power station plant is markedly increased.

Abstract: A pressure suppressing and aerosol scrubbing system configured to be located between low pressure upper containments associated with modular reactor vessels is described. In one embodiment, the pressure suppression and scrubbing system includes a water tank having connected, partially filled water chambers and a vertical baffle having horizontal vent holes positioned near the bottom of the tank. Each water chamber is connected by a vent/relief line to one of the respective rectangular upper containments. The partially filled water tank assures that the respective containments are isolated from each other under normal operating conditions due to the water trap inherent in the system. In the event that an accident occurs in one of the reactors, the affected containment is heated by the sodium spray and/or pool fire and such heat forces its way through the pressure suppressing and scrubbing system to the unaffected reactor containment.

Abstract: A system for suppressing the pressure inside the containment of a BWR following a postulated accident. A piping subsystem is provided which features a main process pipe that communicates the wetwell airspace to a connection point downstream of the guard charcoal bed in an offgas system and upstream of the main bank of delay charcoal beds which give extensive holdup to offgases. The main process pipe is fitted with both inboard and outboard containment isolation valves. Also incorporated in the main process pipe is a low-differential-pressure rupture disk which prevents any gas outflow in this piping whatsoever until or unless rupture occurs by virtue of pressure inside this main process pipe on the wetwell airspace side of the disk exceeding the design opening (rupture) pressure differential. The charcoal holds up the radioactive species in the noncondensable gas from the wetwell plenum by adsorption, allowing time for radioactive decay before the gas is vented to the environs.

Abstract: A method for enhancing the diffusion of gas bubbles or voids attached to impurity precipitates, and biasing their direction of migration out of the host metal (or metal alloy) by applying a temperature gradient across the host metal (or metal alloy). In the preferred embodiment of the present invention, the impurity metal is insoluble in the host metal and has a melting point lower than the melting point of the host material. Also, preferably the impurity metal is lead or indium and the host metal is aluminum or a metal alloy.

Abstract: A reactor coolant debris filter for insertion within a nuclear fuel assembly support.

Abstract: Crystals of the Zeolite Analcime (Analcite) Na.sub.2 O.Al.sub.2 O.sub.3.4SiO.sub.2.2H.sub.2 O are provided having a largest dimension greater than 50 micron. A method for preparing such crystals by mixing aqueous solutions of aluminium sulphate and sodium metasilicate, allowing a gel to form then heating, is provided. The presence of an organic water-miscible base encourages an increased crystal size. The crystals retain water strongly and a use for them in long term immobilisation of tritiated waste water is provided.

Abstract: The apparatus is provided with a line (1) connected to the containment for feeding air to a water bath (5). The line (1) is connected to plurality of nozzles (4) disposed in the water bath (5) having at least one perforate baffle plate (27) disposed above said nozzles. A set (6) of static mixing elements (30, 31, 32) surrounded by a jacket (7) is disposed above said baffle plate (27). A dry separating stage is disposed above the water bath (5) and the set (6) and consists of an entry separator (8) and an agglomerator (9) which are in the form of annular discs. Air emerging from the set successfully flows through the entry separator (8) and the agglomerator (9) in opposite directions. The entry separator (8) and the agglomerator (9) consist of static mixing elements.

Abstract: A process for obtaining a sample from an atmosphere in a closed gastight vessel, preferably from a reactor safety vessel of a nuclear power station, includes passing a sample through a venturi nozzle immediately upon entry of the sample into a sample-taking container in a vessel. The sample is mixed in the venturi nozzle with a transport fluid serving as a washing liquid. Gaseous constituents of the sample being soluble and/or condensable in the washing liquid are subsequently discharged together with the washing liquid from the sample-taking container and from the vessel by triggering a pressure reduction. A device for obtaining samples from an atmosphere in a closed gastight vessel, preferably from a reactor safety vessel of a nuclear power station, includes a sample-taking container having a bottom and a given volume. A washing liquid is disposed in the sample-taking container and has a volume being at most approximately equal to half of the given volume.

Abstract: A system for collecting, transferring and storing radioactive gas released from other radioactive materials. In the described process, gas pump (24) removes gas from a headspace volume within an unvented radioactive material storage vessel (8). The gas is cooled in an aftercooler (28) and discharged into a receiver (32). As pressure in receiver (32) increases, compressed gas is transferred to a selected pressurized decay vessel (44 or 50), in which the radioactive gas remains for a predetermined decay period. After expiration of decay period, decayed gas is either recycled back to the radioactive material storage vessel (8) via recycled gas recirculation line (52) and pressure reducing valve (54), or is discharged to atmosphere through an activated carbon and high-efficiency particulate filters (48), removing remaining undecayed radioactive gas and particulate daughter products.

Abstract: A vent filter assembly may be disposed in a wall of a sealed waste container containing radioactive waste or the like and utilized for venting gases. The vent filter includes a housing coupled to the container. The housing includes a first opening communicating with an interior of the container and a second opening communicating with an exterior of the container. The housing defines a gas flow path between the first and second openings. A filter is coupled to the housing and disposed across the gas flow path such that gas flowing between the openings flows through the filter. The filter includes a porous metal hydrophobic filter medium. The components of the assembly may be fabricated from materials that are durable and resistant to deterioration due to elements stored within the container, as well as environmental elements. Further, the components may be fabricated from the same or similar materials or materials which are compatible with one another.

Abstract: A method for pressure relief of a containment of a nuclear power plant includes heating a washing fluid in a filter disposed inside a containment at a rated heating power through a thermal bridge, with a gas-steam mixture filling the containment, prior to initial operation of the filter. The thermal bridge is rendered substantially ineffective in an operating state of the filter, leaving the washing fluid with a continuous rated heating power being negligible in terms of filtration. In a nuclear power plant having a containment, a system for pressure relief of the containment includes a filter being disposed inside the containment and having a container. At least part of the container has two walls defining a chamber between the walls. A heat-conducting fluid at least partly fills the chamber during a heating period and is at least half evaporated after attainment of an operating temperature.

Abstract: Where a concrete structure (12) has been contaminated with tritium (whether as gas or as water) the tritium atoms take the place of ordinary hydrogen atoms in water and in hydroxyl groups in the concrete, rendering it radioactive. The degree of contamination may be reduced by irradiating the surface with microwaves to vaporize water, while extracting water vapor from the surface region through a dust filter (28) and a water trap (30). This can considerably reduce the radioactivity, and hence the cost of disposal of the concrete.

Abstract: In a device for monitoring the atmosphere within the containment shell (1) of a reactor plant, a sample removal means (41) is provided in the containment shell, from which a gas mixture is led via a measuring line (42) through a measuring zone (14) and subsequently discarded. The concentration of the gas is reduced upstream of the measuring zone (14) in a dilution plant (40).

Abstract: In addition to the metal-fiber filter and molecular sieve of a depressurization system for the containment vessel of a nuclear reactor, within an auxiliary equipment building adjacent the structure surrounding the containment vessel, at least one metal-fiber filter and at least one molecular sieve form filter elements of a system for evacuating the space between the structure and the containment.

Abstract: A containment, such as a glovebox (3), includes an extract system comprising an extract suction means, a filter housing (4), and a vortex amplifier (1) controlling the extent of suction by the suction means from the containment, wherein the vortex amplifier is removably mounted in an opening in a wall (2) of the containment, and the filter housing is mounted relative to the containment in such a manner that a filter (22) within the housing can be posted through an opening into the containment.The vortex amplifier is removable for cleaning.The filter housing may be mounted on the exterior of the containment in-line with the opening in which the vortex amplifier is mounted whereby the filter can be posted through the opening in which the vortex amplifier is mounted upon removal of the vortex amplifier.

Abstract: A method for pressure relief of a containment of a nuclear power plant includes heating a washing fluid in a filter disposed inside a containment at a rated heating power through a thermal bridge, with a gas-steam mixture filling the containment, prior to initial operation of the filter. The thermal bridge is rendered substantially ineffective in an operating state of the filter, leaving the washing fluid with a continuous rated heating power being negligible in terms of filtration. In a nuclear power plant having a containment, a system for pressure relief of the containment includes a filter being disposed inside the containment and having a container. At least part of the container has two walls defining a chamber between the walls. A heat-conducting fluid at least partly fills the chamber during a heating period and is at least half evaporated after attainment of an operating temperature.

Abstract: A method and apparatus for use in conjunction with a passive nuclear reactor containment cooling system to significantly reduce the release of radiation and resulting off-site doses is disclosed. Gases that may contain radioactive materials are drawn from a penetration room and pass through a filter prior to being fed into the passive containment airflow path. Low pressure areas are created in the passive containment airflow path by means of eductor/airfoils. Such low pressure zones draw the gases from the penetration rooms.

Abstract: A unique clean-up sub-system for chemical decontamination of nuclear reactor primary systems is disclosed. Chemically-processed fluids containing suspended and dissolved solids are directed through a back-flushable filter and, thereafter, through one or more cartridge filters. After this initial filtering of suspended solids, the process fluid is directed to one or more demineralizer banks for removal of dissolved solids, followed by additional cartridge filtering to remove any resin fines carried out of the demineralizer banks. After final filtering, the process fluids are returned to the primary system, with or without chemical injection.

Abstract: A device for relieving the pressure in a containment of a nuclear power station. The device includes a filter unit for filtering compressed air from the containment and discharging the air to the atmosphere. Radioactive substances entrained in the compressed air are removed. The filter unit includes an aerosol-filter subunit located within the containment, and a molecular-sieve subunit for iodine filtering located outside the containment in an auxiliary equipment building. Ducts and fittings connect the subunits of the filter unit. At least one duct extends through the containment wall and can be opened and closed by fittings which can be actuated in the event of a failure.

Abstract: Tritium and deuterium are separated from a gaseous mixture thereof, derived from a nuclear fusion reactor or some other source, by providing a casing with a bulk getter therein for absorbing the gaseous mixture to produce an initial loading of the getter, partially desorbing the getter to produce a desorbed mixture which is tritium-enriched, pumping the desorbed mixture into a separate container, the remaining gaseous loading in the getter being deuterium-enriched, desorbing the getter to a substantially greater extent to produce a deuterium-enriched gaseous mixture, and removing the deuterium-enriched mixture into another container. The bulk getter may comprise a zirconium-aluminum alloy, or a zirconium-vanadium-iron alloy. The partial desorption may reduce the loading by approximately fifty percent. The basic procedure may be extended to produce a multistage isotope separator, including at least one additional bulk getter into which the tritium-enriched mixture is absorbed.

Abstract: A filter for a respirator for removal of tritiated water having a housing with fluid inlet and output ports. A filter chamber is interposed between and in communication with the inlet and outlet for containing the tritium filter medium. A tritium filter media is selected from a particulate activated carbon or a particulate silica gel in which the media has a moisture content of from about 25% to 40% by weight of the media and a particulate distribution size range of from 6.times.20 to 12.times.30.

Abstract: An atmospheric tritium sampler is provided which uses a carrier gas comprised of hydrogen gas and a diluting gas, mixed in a nonexplosive concentration. Sample air and carrier gas are drawn into and mixed in a manifold. A regulator meters the carrier gas flow to the manifold. The air sample/carrier gas mixture is pulled through a first moisture trap which adsorbs water from the air sample. The mixture then passes through a combustion chamber where hydrogen gas in the form of H.sub.2 or HT is combusted into water. The manufactured water is transported by the air stream to a second moisture trap where it is adsorbed. The air is then discharged back into the atmosphere by means of a pump.

Abstract: A clamping arrangement for stainless steel fiber filter elements in the pressure relief channel of a safety containment of a nuclear installation. The filter elements are engaged at their edges by a clamping structure which is fully disposed within the duct walls defining the relief channel. The clamping arrangement includes a support frame mounted on the duct walls and a clamping frame disposed on the support frame and clamped thereto with the edges of the respective filter element clamped therebetween such that any leakage through the clamping arrangement is still contained by the duct walls.

Abstract: Iodine and organic iodine compounds which may be radioactive and which may be found in waste gases or vapors from nuclear reactors can be removed from such gases or vapors by passing the iodine or organic iodine compound-containing gases or vapors through a layer of binder-free silver-exchanged molecular sieve granulates of the faujasite type.

Abstract: A high-temperature reactor with a reactor core containing fuel elements crossed by a cooling gas circuit comprises a malfunction filter for filtering metal fission products discharged from the fuel elements in the event of core overheating. The filter is mounted in the cooling gas circuit outside the reactor core and consists of a carbon which is incompletely graphitized, or is not graphitized at all.

Abstract: The exhaust gas of a fusion reactor contains, besides non-burnt fuel (tritium and deuterium) and helium, the "ash" from the nuclear fusion reaction a number of impurities with the radioactive tritium and/or deuterium chemically bound to them. In order to clean the exhaust gas, both the elemental and the chemically bound tritium and/or deuterium fractions are separated from the exhaust gas. Separation is achieved exclusively by physical and catalytical process steps, namely a palladium/silver permeator, a CuO/Cr.sub.2 O.sub.3 /ZnO catalyst bed and a further palladium/silver permeator containing a nickel/aluminum oxide bulk catalyst.

Abstract: A pressurized gas discharge system for the safety containment of a nuclear reactor includes a conduit structure connected to the containment and consisting of a plurality of modular conduit units which are flanged together end-to-end, each having flanged side openings with filter frame members including stainless steel fiber filter packs flanged thereto in end-to-end relationship. The filter packs extend fully across the frame members and have their circumferential edges clamped between the flanges of adjacent frame members so that in the clamped areas the filter packs are reduced in thickness to a fraction of their original thickness, the flanges having U-shaped members disposed on their faces such that the legs of the U-shaped member project toward the adjacent flange and provide two seal strips with the edges of the filter packs compressed therebetween.

Abstract: A nuclear power plant includes a containment for containing activity carriers. An outlet in the form of an excess pressure safety device leads out of the containment. A filter connects the outlet to the atmosphere. The filter includes a container, a washing fluid disposed in the container, a Venturi scrubber being integrated in the container and connected to the outlet, the container having an upper region with a gas outlet, and a stack connected to the gas outlet.

Abstract: Gases and entrained particulate matter are automatically vented from a nuclear containment as pressure approaches a set point of the containment design during a postulated accident scenario. A porous bed filter is submerged in a tank of water, affording a first stage of filtration of the vented gases and entrained particulate matter passing in an upward flow from the bottom of the tank through the porous filter bed and a second, pool scrubbing stage as the flow proceeds upwardly through a central region of the water above the filter with accompanying decay heat removal prior to release of the gases from the water surface and discharge to atmosphere. The water returns through a down-flow path defined by an annular boundary region surrounding the central region of the water volume, in a pumping function for repeating the mixing and two-stage flow, and purges the porous filter bed.

Abstract: Process for decontaminating exhaust gas from a fusion reactor fuel cycle of exhaust gas components containing at least one heavy hydrogen isotope selected from tritium and deuterium in compound form, in which the at least one heavy hydrogen isotope is liberated from its compound, separated out from the exhaust gas and fed back into the fuel cycle, the compound form being at least one compound which is ammonia or a hydrocarbon, comprising:(a) converting the at least one heavy hydrogen-containing compound into its elements in the exhaust gas by cracking the at least one heavy hydrogen containing compound with a cracking medium to liberate the hydrogen isotope,(b) passing the liberated hydrogen isotope through a membrane to separate out the liberated hydrogen isotope from the flow of the remaining exhaust gas, and(c) discharging the remaining decontaminated exhaust gas into the surrounding air.

Abstract: Method for removal of radioactive cesium from a hot vapor, such as high temperature steam, including the steps of passing input hot vapor containing radioactive cesium into a bed of silicate glass particles and chemically incorporating radioactive cesium in the silicate glass particles at a temperature of at least about 700.degree. F.