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.

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.

A methyl iodide adsorber, comprising a zeolite containing at least one iodide-adsorbing metal or a compound thereof, wherein the zeolite is a hydrophobic zeolite. Also, a use of the adsorber and a method for the adsorption of methyl iodide.

An autonomously functioning ignition system, even though it is simple in design, allows for the reliable ignition of combustible gas mixtures that are only slightly above the ignition limit. The ignition system for igniting combustible gas mixtures, particularly in a containment structure of a nuclear facility, includes an electric ignition element and a thermoelectric generator that forms a source of current for the ignition element. A catalytic recombiner for the gas mixture, which is configured as a flow channel for the gas mixture, forms a heat source for the thermoelectric generator.

An autonomously functioning ignition system, even though it is simple in design, allows for the reliable ignition of combustible gas mixtures that are only slightly above the ignition limit. The ignition system for igniting combustible gas mixtures, particularly in a containment structure of a nuclear facility, includes an electric ignition element and a thermoelectric generator that forms a source of current for the ignition element. A catalytic recombiner for the gas mixture, which is configured as a flow channel for the gas mixture, forms a heat source for the thermoelectric generator.

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.

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.

An ion exchange system includes one or more strategies to reduce the amount of hydrogen gas inside an ion exchange column when the column is offline or disposed of. The ion exchange system comprises an ion exchange column including a housing and ion exchange media positioned in the housing. The ion exchange column can include one or more of the following: (1) an oxide material that limits the production of hydrogen gas from radiolysis, (2) a hydrogen scavenging material that removes or scavenges hydrogen gas inside the column, and (3) a hydrogen catalytic material that catalyzes the reaction of hydrogen and oxygen inside the column.

An ion exchange system includes one or more strategies to reduce the amount of hydrogen gas inside an ion exchange column when the column is offline or disposed of. The ion exchange system comprises an ion exchange column including a housing and ion exchange media positioned in the housing. The ion exchange column can include one or more of the following: (1) an oxide material that limits the production of hydrogen gas from radiolysis, (2) a hydrogen scavenging material that removes or scavenges hydrogen gas inside the column, and (3) a hydrogen catalytic material that catalyzes the reaction of hydrogen and oxygen inside the column.

A process of producing a catalyst entails providing an alumina substrate and adhering a noble metal consisting of either platinum or palladium to an outer surface of the alumina substrate to form a surface coating without penetrating into a central portion of the substrate. The noble metal may be calcined in a presence of organic compounds that increase the viscosity of a liquid carrying the noble metal to thereby minimize penetration into the central portion of the substrate and that also increase the yield of metal oxides during calcination thereby making the catalyst more active.