Abstract: A depressurization and cooling system for steam and/or condensable gases located in a containment. The system contains a steam condenser having an upstream port connected to the containment through an exhaust line and a downstream port connected to the containment through a backfeed line. The backfeed line contains a backfeed compressor. A re-cooling system for re-cooling the steam condenser is provided. The depressurization and cooling system is effective for re-cooling of the steam condenser. Accordingly, this is achieved as the re-cooling system is self-sustainable.

Abstract: A nuclear system, in particular a nuclear power plant (2), includes a containment (4) and an associated venting system (6), which has a venting line (8) connected to the containment (4), and an emission monitoring system (16) is provided for the venting system (6). A representative measuring sample is taken from the clean gas line of the venting system, and can be tested for aerosol-type decomposition products online in a subsequent analysis system. The emission monitoring system comprises a sampling line (44) for a sample flow branching off from the venting line (8) and leading into a sample container (32), and a recirculation line (54) leading from the sample container (32) to the venting line (8). The sample container (32) contains a wet scrubber (34) for the sample flow, as well as an ionisation separator (64) downstream of the wet scrubber (34) in relation to the sample flow. A liquid removal line (78) leads from the sample container (32) to an analysis unit (20).

Abstract: A catalytic recombiner and filter apparatus is especially suited for placement in a containment of a nuclear reactor. The apparatus has a natural convection flow duct with a number of catalytic elements for recombining hydrogen and oxygen contained in a gas flow through the flow duct. The catalytic recombiner and filter apparatus provides for reliable hydrogen reduction and iodine filtering for a gas flow even for a comparatively long period of operation. The catalytic recombiner and filter apparatus includes a number of adsorber elements with iodine adsorbing surfaces and with macroscopic flow channels in between. The iodine adsorbing surfaces are flown over by the gas flow, and the adsorber elements are arranged, when in use, downstream of the catalytic elements in a direction of the gas flow.

Abstract: A sample container, sampling system and operating methods permit representative sampling from a liquid phase or boiling liquid, a gaseous phase, a containment sump, containment atmosphere, or condensation chamber of a nuclear power plant following a severe accident. A sample container obtaining an environmental sample includes an outer chamber surrounded by an outer container wall, being directly fluidically connected to the environment through a passage opening in the outer container wall and being fillable with a liquid at least in a base region. An inner chamber surrounded by an inner container wall is fluidically connected to the base region through a passage opening in the inner container wall, has connections for sampling and conveyor medium lines and is otherwise pressure and media tightly sealed from the environment. A pneumatically or hydraulically actuatable closure device for the passage opening between the outer and inner chambers has an actuation medium line connection.

Abstract: A catalytic recombiner and filter apparatus is especially suited for placement in a containment of a nuclear reactor. The apparatus has a natural convection flow duct with a number of catalytic elements for recombining hydrogen and oxygen contained in a gas flow through the flow duct. The catalytic recombiner and filter apparatus provides for reliable hydrogen reduction and iodine filtering for a gas flow even for a comparatively long period of operation. The catalytic recombiner and filter apparatus includes a number of adsorber elements with iodine adsorbing surfaces and with macroscopic flow channels in between. The iodine adsorbing surfaces are flown over by the gas flow, and the adsorber elements are arranged, when in use, downstream of the catalytic elements in a direction of the gas flow.

Abstract: 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.

Abstract: A ventilation system for an operating space accessible to operators in a nuclear installation is intended to allow a supply of decontaminated fresh air for a period of a few hours in the event of serious accidents involving the release of radioactive activity. In particular, the component of radioactive inert gases in the fresh air supplied to the operating space should be as small as possible. For this purpose, the ventilation system has a supply air line that is guided from an external inlet to the operating space, and into which a first fan and a first inert gas adsorber column are connected. An exhaust air line is guided from the operating space to an external outlet, and into which a second fan and a second inert gas adsorber column are connected. A switching device is provided for interchanging the roles of the first and second inert gas adsorber columns.

Abstract: A depressurization and cooling system for steam and/or condensable gases located in a containment. The system contains a steam condenser having an upstream port connected to the containment through an exhaust line and a downstream port connected to the containment through a backfeed line. The backfeed line contains a backfeed compressor. A re-cooling system for re-cooling the steam condenser is provided. The depressurization and cooling system is effective for re-cooling of the steam condenser. Accordingly, this is achieved as the re-cooling system is self-sustainable.

Abstract: A sample container, sampling system and operating methods permit representative sampling from a liquid phase or boiling liquid, a gaseous phase, a containment sump, containment atmosphere, or condensation chamber of a nuclear power plant following a severe accident. A sample container obtaining an environmental sample includes an outer chamber surrounded by an outer container wall, being directly fluidically connected to the environment through a passage opening in the outer container wall and being fillable with a liquid at least in a base region. An inner chamber surrounded by an inner container wall is fluidically connected to the base region through a passage opening in the inner container wall, has connections for sampling and conveyor medium lines and is otherwise pressure and media tightly sealed from the environment. A pneumatically or hydraulically actuatable closure device for the passage opening between the outer and inner chambers has an actuation medium line connection.

Abstract: An emission monitoring system for a venting system of a nuclear power plant is configured for low consumption of energy and high reliability. The emission monitoring system has a pressure relief line connected to a containment and contains a high-pressure section, a low-pressure section, and a sampling line. The sampling line opens into the low-pressure section of the pressure relief line and is guided from there to a functional path and through the sampling line steam flows. A jet pump containing a pump fluid connector, a suction connector and an outlet connector is provided. A pump fluid feed line has an inlet side opening into the high-pressure section of the pressure relief line and is guided from there to the jet pump and connected to the pump fluid connector. A sample return line is guided from the functional path to the jet pump and connected to the suction connector.

Abstract: A method for the quantitative analysis of the composition of a gas mixture is specifically suited for the analysis of the atmosphere of a containment in a nuclear installation. Even under difficult conditions, this method enables the simple, reliable and as direct as possible determination of physical parameters, thereby permitting the characteristic definition of the ignition field and the combustion behavior of the gas mixture. A measuring device is provided with a thermal conductivity detector with a first measuring bridge, a thermal tonality detector with a second measuring bridge, and a common evaluation unit. With reference to bridge voltages present on the two measuring bridges, the hydrogen content and the oxygen content are simultaneously determined in the evaluation unit.

Abstract: A ventilation system for an operating space accessible to operators in a nuclear installation is intended to allow a supply of decontaminated fresh air for a period of a few hours in the event of serious accidents involving the release of radioactive activity. In particular, the component of radioactive inert gases in the fresh air supplied to the operating space should be as small as possible. For this purpose, the ventilation system has a supply air line that is guided from an external inlet to the operating space, and into which a first fan and a first inert gas adsorber column are connected. An exhaust air line is guided from the operating space to an external outlet, and into which a second fan and a second inert gas adsorber column are connected. A switching device is provided for interchanging the roles of the first and second inert gas adsorber columns.

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: A method for the quantitative analysis of the composition of a gas mixture is specifically suited for the analysis of the atmosphere of a containment in a nuclear installation. Even under difficult conditions, this method enables the simple, reliable and as direct as possible determination of physical parameters, thereby permitting the characteristic definition of the ignition field and the combustion behavior of the gas mixture. A measuring device is provided with a thermal conductivity detector with a first measuring bridge, a thermal tonality detector with a second measuring bridge, and a common evaluation unit. With reference to bridge voltages present on the two measuring bridges, the hydrogen content and the oxygen content are simultaneously determined in the evaluation unit.

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 emission monitoring system for a venting system of a nuclear power plant is configured for low consumption of energy while having high reliability of measurement results. The emission monitoring system has a pressure relief line connected to a containment and contains a high-pressure section, a low-pressure section, and a sampling line, which, on the inlet side, opens into the low-pressure section of the pressure relief line and is guided from there to a functional path through which steam flows. An ejector containing a pump fluid connector, a suction connector and an outlet connector is provided. A pump fluid feed line has an inlet side opening into the high-pressure section of the pressure relief line and is guided from there to the ejector and connected to the pump fluid connector. A sample return line is guided from the functional path to the ejector and connected to the suction connector.

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 containment protection system for treating air in a containment of a nuclear facility in the case of accidents involving extensive release of hydrogen and steam is to be able to effectively relieve such conditions in a largely passive manner. Accordingly, the containment protection system has for a circuit, which contains a conduction system and is provided for connecting to the containment, out of the containment and back again for a fluid flow. The system has a recombination device for recombining hydrogen contained in the fluid flow with oxygen to form steam, a condensation device connected downstream of the recombination device for condensing steam fractions contained in the fluid flow with measures for diverting the condensate out of the fluid flow, and a drive device for the fluid flow. A heat exchanger at least partial re-cools the condensation device.

Abstract: A method treats a flow gas that is guided via a catalytic adsorber module to oxidize contaminants carried in the flow gas. The method reliably purifies the flow gas using equipment that is held to a comparatively low level of complexity. To this end, the flow gas is guided in a first purification step via a first catalytic adsorber module to oxidize contaminants carried along therewith, during which molecular or atomic oxygen is added to the flow gas, and the flow gas mixed with the added oxygen is guided in a second purification step via an oxidation catalyst. The flow gas flowing away from the oxidation catalyst is guided in a third purification step via a second catalytic adsorber module to reduce excessive oxygen.

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.