WO2000030123A1 - Recombiner for the efficient elimination of hydrogen from atmospheres created as a result of malfunctioning - Google Patents

Recombiner for the efficient elimination of hydrogen from atmospheres created as a result of malfunctioning Download PDF

Info

Publication number
WO2000030123A1
WO2000030123A1 PCT/EP1999/008738 EP9908738W WO0030123A1 WO 2000030123 A1 WO2000030123 A1 WO 2000030123A1 EP 9908738 W EP9908738 W EP 9908738W WO 0030123 A1 WO0030123 A1 WO 0030123A1
Authority
WO
WIPO (PCT)
Prior art keywords
housing
recombiner
plates
recombiner according
openings
Prior art date
Application number
PCT/EP1999/008738
Other languages
German (de)
French (fr)
Inventor
Peter BRÖCKERHOFF
Werner Von Lensa
Ernst Arndt Reinecke
Original Assignee
Forschungszentrum Jülich GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Forschungszentrum Jülich GmbH filed Critical Forschungszentrum Jülich GmbH
Publication of WO2000030123A1 publication Critical patent/WO2000030123A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B5/00—Water
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J12/00—Chemical processes in general for reacting gaseous media with gaseous media; Apparatus specially adapted therefor
    • B01J12/007—Chemical processes in general for reacting gaseous media with gaseous media; Apparatus specially adapted therefor in the presence of catalytically active bodies, e.g. porous plates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/0006—Controlling or regulating processes
    • B01J19/002—Avoiding undesirable reactions or side-effects, e.g. avoiding explosions, or improving the yield by suppressing side-reactions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/0053—Details of the reactor
    • B01J19/006—Baffles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/24—Stationary reactors without moving elements inside
    • B01J19/248—Reactors comprising multiple separated flow channels
    • B01J19/249—Plate-type reactors
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C19/00—Arrangements for treating, for handling, or for facilitating the handling of, fuel or other materials which are used within the reactor, e.g. within its pressure vessel
    • G21C19/28—Arrangements for introducing fluent material into the reactor core; Arrangements for removing fluent material from the reactor core
    • G21C19/30—Arrangements for introducing fluent material into the reactor core; Arrangements for removing fluent material from the reactor core with continuous purification of circulating fluent material, e.g. by extraction of fission products deterioration or corrosion products, impurities, e.g. by cold traps
    • G21C19/317—Recombination devices for radiolytic dissociation products
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C9/00—Emergency protection arrangements structurally associated with the reactor, e.g. safety valves provided with pressure equalisation devices
    • G21C9/04—Means for suppressing fires ; Earthquake protection
    • G21C9/06—Means for preventing accumulation of explosives gases, e.g. recombiners
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00049—Controlling or regulating processes
    • B01J2219/00245—Avoiding undesirable reactions or side-effects
    • B01J2219/00259—Preventing runaway of the chemical reaction
    • B01J2219/00263—Preventing explosion of the chemical mixture
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/24—Stationary reactors without moving elements inside
    • B01J2219/2401—Reactors comprising multiple separate flow channels
    • B01J2219/245—Plate-type reactors
    • B01J2219/2451—Geometry of the reactor
    • B01J2219/2453—Plates arranged in parallel
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/24—Stationary reactors without moving elements inside
    • B01J2219/2401—Reactors comprising multiple separate flow channels
    • B01J2219/245—Plate-type reactors
    • B01J2219/2476—Construction materials
    • B01J2219/2477—Construction materials of the catalysts
    • B01J2219/2479—Catalysts coated on the surface of plates or inserts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/24—Stationary reactors without moving elements inside
    • B01J2219/2401—Reactors comprising multiple separate flow channels
    • B01J2219/245—Plate-type reactors
    • B01J2219/2476—Construction materials
    • B01J2219/2477—Construction materials of the catalysts
    • B01J2219/2482—Catalytically active foils; Plates having catalytically activity on their own
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/24—Stationary reactors without moving elements inside
    • B01J2219/2401—Reactors comprising multiple separate flow channels
    • B01J2219/245—Plate-type reactors
    • B01J2219/2491—Other constructional details
    • B01J2219/2498—Additional structures inserted in the channels, e.g. plates, catalyst holding meshes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/30—Nuclear fission reactors

Definitions

  • the invention relates to devices with which released or accidental accrued hydrogen from non-inertized rooms, for. B. containment of pressure and non-inertized boiling water reactors, which in addition to hydrogen also contain water vapor, air, aerosols and other gases, can be effectively eliminated without reignition.
  • the hydrogen can be present in the presence of atmospheric oxygen, e.g. B. by means of catalytic processes, recombined to water vapor within the device.
  • Preventive safety precautions consist in inerting the gas volumes with nitrogen, as has already been done in the case of boiling water reactors. Discussed countermeasures, some of which have already been implemented, are catalytic recombinerers. With the help of this, the hydrogen produced is catalytically recombined both inside and outside the ignition limits, ie. H. converted into water vapor while generating heat. Hydrogen contents with concentrations within the ignition limits can also be burned off conventionally after spark ignition. However, the processes occurring here cannot be controlled, so that the above-mentioned reactions which could endanger the system may occur.
  • Both thermal and catalytic recombiners have been developed to remove the hydrogen generated during normal operation and in the event of an accident, which recombine the hydrogen with the oxygen in the air in water vapor. Preference is given to catalytic systems which work passively, ie self-starting and without an external energy supply, to ensure availability during an incident.
  • catalytic systems which work passively, ie self-starting and without an external energy supply, to ensure availability during an incident.
  • There are two types of recombiner both metallic plates or foils and highly porous granules, to which platinum or palladium is applied as a catalyst, being used as substrates.
  • Several foils and pellet packages - the pellets are held together by wire nets to form packages - are arranged vertically and parallel to each other in sheet metal housings.
  • the hydrogen / air mixture enters the housing at the bottom.
  • the reaction starts on the catalytically coated surfaces.
  • the mixture or the reaction products flow over the surfaces as a result of the thermal buoy
  • the technical problem of the present invention therefore consists in the controlled implementation of both small and large amounts of hydrogen with the atmospheric oxygen present in the security containers in a wide concentration range and to avoid ignition of the gas mixture with subsequent explosion by means of special devices in the inlet and outlet of the recombiner.
  • a recombiner for removing hydrogen from accident atmospheres which has a housing which specifies a longitudinal direction for a flow and at least one opening at both ends in the longitudinal direction. has.
  • the recombiner also has at least one catalyst element which is arranged in the housing.
  • a device for dividing the cross section of the housing into partial cross sections is provided at least one of the openings within the housing. The division into partial cross sections effectively suppresses both the formation and the spread of explosive combustions, so that the flames or the detonation waves that may arise within the recombiner do not spread outside the recombiner.
  • the device for dividing the cross section of the housing is designed as a porous structure, such as a mesh or a perforated plate, the device extending transversely to the direction of flow through the housing over essentially the entire cross section of the housing Housing extends and wherein the diameter of the openings of the device for dividing the cross section of the housing is smaller than a predetermined quenching distance.
  • a device for dividing the cross section of the housing can also be referred to as a flame flashback.
  • a flame non-return valve has the task of quickly distributing and dissipating the heat generated by the flame and thus preventing an explosion-like expansion of the detonation caused by the flame. If, despite all the precautionary measures that have been taken within the recombiner, an ignition of the hydrogen-rich gas mixture on a catalytically active surface leads to a subsequent homogeneous gas phase reaction, the heat generated during the combustion (deflagration) will quickly and safely dissipate the device arranged at the opening of the housing of the recombiner device for dividing the cross section of the housing, the flame flashback, dissipated.
  • the recombiner does not become a source for extensive burns or even detonations within the containment.
  • the openings in the porous structure are dimensioned so that they do not exceed a critical size, the so-called “extinguishing distance". This extinguishing distance depends on the condition of the combustible or explosive gas mixture and is determined for the respective type of recombiner and its area of application.
  • the porous structure of the device for dividing the cross section of the housing is preferably cooled by a cooling device.
  • the device for dividing the cross section of the housing into partial cross sections has plates or foils which are arranged within the housing, extend along the flow direction of the housing and the volume of the housing at least in the region of the openings divided into partial volumes.
  • This embodiment is based on the knowledge that detonations only propagate in geometries whose dimensions are larger than the dimensions of so-called "detonation cells".
  • the size of a detonation cell depends on the mixture concentration and the pressure and temperature that are present in the gas mixture. For different geometries, e.g. B. gaps or pipes from which detonation waves can emerge in a room, critical dimensions can be determined as a multiple of the detonation cell.
  • the plates or foils of the device for dividing the cross section of the housing are therefore designed such that their spacing is less than a third of the size of the detonation cell to prevent the propagation of a detonation within the channels and less than 3 to prevent the detonation wave from escaping the channel into the free volume.
  • the size of the cell depends on the state variables of the gas mixture.
  • the device described above for dividing the cross section of the housing into partial cross sections can also be referred to as a detonation barrier.
  • the plates or foils of the device for dividing the cross section of the housing preferably form a rectangular structure, so that adjacent flow channels through the housing of the recombiner each have a similar size and shape.
  • additional stability is achieved which, especially when detonations occur, prevents the structure built up by the plates from being destroyed due to the detonation forces and thus the effect of the detonation barrier being released.
  • the plates or foils of the device for dividing the cross section of the housing in the inner regions of the housing are preferably coated with catalytically active materials in order to also bring about a reaction of the hydrogen in the gas mixture on the surfaces of these plates and foils.
  • the plates or foils are preferably in the area of the openings at the ends. that of the housing is not or only to a small extent coated with catalytically active material, so that a further conversion of the hydrogen and thus a further generation of heat is prevented in these areas.
  • reflectors are arranged at the ends of the partial volumes formed by the plates or foils in the region of the openings of the housing, which reflectors preferably have a low flow resistance in the direction of entry into the housing and a higher flow resistance in the direction of exit from the housing . Furthermore, the reflectors extend essentially over the entire width of the plates or foils arranged within the housing of the recombiner. These reflectors represent an additional measure to at least partially reflect detonation waves that emerge from the partial volumes and thus prevent the detonation waves from escaping from the housing of the recombiner.
  • Fig. 1 shows a first embodiment of the recombiner according to the invention in cross section and Fig. 2 shows a second embodiment of the recombiner according to the invention in cross section.
  • the recombiner has a housing 2 which specifies a longitudinal direction for a gas mixture to flow through from an accident atmosphere within a containment of a reactor.
  • the housing 2 has an opening 4 and 6 at both ends in the longitudinal direction, which is oriented from bottom to top in FIG. 1.
  • a plurality of catalytic converter elements 7 are arranged in the housing 2, the catalytic converter elements 7 shown being catalytic converter modules through which the gas mixture flows and which recombine, ie. H. a reaction of the hydrogen from the gas mixture with catalytically active structures contained within the catalyst modules.
  • two different devices 8 are provided for dividing the cross section of the housing 2 into partial cross sections, each of which is arranged in the vicinity of the openings 4 and 6 and is designed differently, as will be described below.
  • the device 8 is designed as a porous structure 10, wherein, for example, a mesh or a perforated plate can be used as the porous structure 10.
  • a mesh or a perforated plate can be used as the porous structure 10.
  • two nets 10 arranged one above the other in the flow direction are arranged at each opening 4 or 6.
  • Each net 10 extends transversely to the direction of flow through the housing 2 over the entire cross-section of the housing 2.
  • the diameter of the openings of the net 10 is smaller than a predetermined quenching distance.
  • each of the nets 10 acts at the openings 4 and 6 of the housing 2 as a flame barrier, in which the during combustion or deflagration of the hydrogen-rich gas mixture, the heat generated is dissipated quickly and safely, so that the openings 4 and 6 do not become sources of further-reaching burns or detonations within the containment.
  • the critical size depends on the condition of the flammable or explosive gas mixture. So that the heat can be dissipated from the network 10 in sufficient form, the networks 10 shown in FIG. 1 are connected to the solid wall of the housing 2.
  • plates 12 are provided which are arranged within the housing 2 and extend along the flow direction of the housing 2.
  • the volume of the housing 2 is continuous and thus also divided into partial volumes 14 in the area of the openings 4 and 6.
  • the plate or film spacing is chosen as the smaller dimension of the partial volumes 14 so that it is smaller than a predetermined characteristic number, which is a multiple of the detonation cells and represents a value characteristic of the geometry of the partial volumes 14 and of the state variables of the gas mixture .
  • the entire volume of the housing 2, the dimensions of which are larger than the predetermined characteristic number, is thus divided into sufficiently small partial volumes 14 by the plates 12.
  • the design of the device 8 for dividing the cross section of the housing 2 in the form of plates 12 can be referred to as a detonation barrier.
  • Plates or foils 12 formed so that they are up to
  • FIG. 2 shows a second exemplary embodiment of the recombiner according to the invention.
  • the housing 2 of the recombiner has the two previously described configurations of the device 8 for dividing the cross section of the housing into partial cross sections at the openings 4 and 6.
  • FIG. 2 shows that instead of the nets shown in FIG. 1, the porous structure is designed as a perforated plate 10, which is connected to the wall of the housing 2 at the openings 4 and 6. Since a perforated plate is made more solid than a network, stability and heat capacity are greater compared to a network, so that the heat absorption and dissipation can be carried out more efficiently. However, it must be accepted that the number of openings is less than that of a network.
  • the second embodiment of the device 8 for dividing the cross section of the housing 2 into partial cross sections in the form of the plates 12 is also arranged in the housing 2 in the exemplary embodiment shown in FIG. 2.
  • the catalyst elements 7 are designed as flat coatings of the plates 12 with catalyst material, so that the catalytic recombination takes place on the surfaces of the plates 12.
  • the catalytic coating is located in the areas 12A of the plates 12, which is limited to the inner area of the interior of the housing 2.
  • the areas 12B of the plates 12 facing the openings 4 and 6, on the other hand, are not coated with a catalytic material, so that, depending on the direction of flow, no further recombination with heat development takes place at the outlet areas of the openings 4 or 6 and due to the uncoated sections 12B occurring cooling is suppressed or at least reduced an occurring flame development.
  • reflectors 16 are arranged at the ends of the partial volumes 14 in the region of the openings 4 and 6 of the housing. These reflectors have a shape in the longitudinal direction which have a low flow resistance in the direction of entry into the housing 2 and a higher flow resistance for the gas mixture in the direction of exit from the housing 2.
  • a detonation wave propagating from the interior of the housing 2 along the partial volumes 14 is at least partially reflected by the surfaces of the reflectors.
  • the normal outflow and inflow of the gas mixture into the housing 2 of the recombiner is not hampered too much by the reflectors 14.
  • a reflector 16 is arranged at each end of a partial volume 14 and extends essentially over the entire width of the plates 12 arranged within the housing 2. This ensures that a reflector 16 is applied to the entire cross-section of each partial volume.

Abstract

The invention relates to a recombiner for eliminating hydrogen from atmospheres created as a result of malfunctioning. The recombiner comprises a housing which determines a longitudinal direction for a throughflow and which has at least one opening at each end respectively, in the longitudinal direction, and at least one catalyst element, which is situated in the housing. The aim of the invention is to solve the technical problem of reacting both small and large quantities of hydrogen with the atmospheric oxygen that is present in the safety containers, within a broad concentration range and under control, and of preventing a backfire and subsequent explosion by means of particular devices in the inlet or outlet. To this end, a device for dividing the cross-section of the housing into sub-cross-sections is provided inside said housing on at least one of the openings.

Description

Rekombinator zum effektiven Beseitigen von Wasserstoff ausRecombiner for the effective removal of hydrogen from
StörfallatmosphärenIncident atmospheres
Die Erfindung bezieht sich auf Vorrichtungen, mit denen freigesetzter oder störfallbedingt entstandener Wasserstoff aus nichtinertisierten Räumen, z. B. Sicherheitsbehältern von Druck- und nichtinertisierten Siedewasserreaktoren, die neben Wasserstoff auch Wasserdampf, Luft, Aerosole und weitere Gase enthalten, effektiv rückzündungsfrei beseitigt werden kann. Dabei kann der Wasserstoff in Anwesenheit des vorhandenen Luftsauerstoffs, z. B. mittels katalytischer Verfahren, innerhalb der Vorrichtung zu Wasserdampf rekombi- niert werden.The invention relates to devices with which released or accidental accrued hydrogen from non-inertized rooms, for. B. containment of pressure and non-inertized boiling water reactors, which in addition to hydrogen also contain water vapor, air, aerosols and other gases, can be effectively eliminated without reignition. The hydrogen can be present in the presence of atmospheric oxygen, e.g. B. by means of catalytic processes, recombined to water vapor within the device.
Im Verlauf schwerer Störfälle entstehen in wassergekühlten Kernreaktoren (LWR) infolge der Reduktion von Wasserdampf große Mengen Wasserstoff, die in die Sicherheitsbehälter ge- langen. Die maximalen Wasserstoffmengen können sowohl bei Druck- als auch Siedewasserreaktoren etwa 20.000 m^ 3 betra- gen. Aufgrund des sich in den Sicherheitsbehältern (Containments) befindenden Luftsauerstoffs besteht die Gefahr der Bildung zündfähiger Gemische, deren unkontrollierte Entzündung mit anschließender Detonation eine schwere dynamische Druckbeanspruchung der Containmentwände bewirkt. Wasserdampf und Wasserstoff führen darüber hinaus stets zu Druck- und Temperaturerhöhungen der Störfallatmosphäre. Dies ist insbesondere in Siedewasserreaktoren bedeutsam, da die Volumina ihrer Behälter nur etwa 20.000 mn 3 im Vergleich zu 70.000 mn 3 bei Druckwasserreaktoren betragen. Druck- und Temperaturerhöhungen führen zu einer zusätzlichen statischen Beanspruchung der Containmentwände. Außerdem besteht bei Leckagen infolge des Überdrucks die Gefahr des Austritts radiotoxischer Substanzen.In the course of serious accidents, water-cooled nuclear reactors (LWR) generate large amounts of hydrogen as a result of the reduction in water vapor, which can get into the containment. The maximum amounts of hydrogen can be around 20,000 m ^ 3 for both pressure and boiling water reactors. Due to the atmospheric oxygen in the containment containers, there is a risk of the formation of ignitable mixtures, the uncontrolled ignition of which, with subsequent detonation, causes heavy dynamic pressure on the containment walls. In addition, water vapor and hydrogen always lead to pressure and temperature increases in the accident atmosphere. This is significant especially in boiling water reactors, since the volumes m n be their containers only about 20,000 to 70,000 m 3 compared n 3 for pressurized water reactors. Increases in pressure and temperature lead to an additional static load on the containment walls. In addition, there is a risk of radiotoxic substances escaping in the event of leakages due to the excess pressure.
Vorbeugende Sicherheitsvorkehrungen bestehen in der Inerti- sierung der Gasvolumina mit Stickstoff, wie sie im Fall der Siedewasserreaktoren bereits vorgenommen worden ist. Diskutierte und zum Teil bereits realisierte Gegenmaßnahmen stel- len katalytische Rekombinatoren dar. Mit deren Hilfe wird der entstandene Wasserstoff sowohl innerhalb als auch außerhalb der Zündgrenzen exotherm katalytisch rekombiniert, d. h. unter Entstehung von Wärme in Wasserdampf umgesetzt. Wasserstoffgehalte mit Konzentrationen innerhalb der Zündgren- zen lassen sich darüber hinaus auch konventionell nach Fremdzündung abbrennen. Die dabei auftretenden Vorgänge sind jedoch nicht kontollierbar, so daß es unter Umständen zu den bereits oben genannten anlagengefährdenden Reaktionen kommen kann.Preventive safety precautions consist in inerting the gas volumes with nitrogen, as has already been done in the case of boiling water reactors. Discussed countermeasures, some of which have already been implemented, are catalytic recombinerers. With the help of this, the hydrogen produced is catalytically recombined both inside and outside the ignition limits, ie. H. converted into water vapor while generating heat. Hydrogen contents with concentrations within the ignition limits can also be burned off conventionally after spark ignition. However, the processes occurring here cannot be controlled, so that the above-mentioned reactions which could endanger the system may occur.
Zur Beseitigung des im Normalbetrieb und störfallbedingt entstehenden Wasserstoffs wurden sowohl thermische als auch katalytische Rekombinatoren entwickelt, die den Wasserstoff mit dem Sauerstoff der Luft in Wasserdampf rekombinieren. Bevorzugt werden katalytische Systeme, die passiv, d. h. selbststartend und ohne externe Energieversorgung, arbeiten, damit die Verfügbarkeit während eines Störfalls gewährleistet ist. Es gibt zwei Rekombinatortypen, wobei als Substrate sowohl metallische Platten oder Folien als auch hochporöses Granulat verwendet werden, auf die Platin bzw. Palladium als Katalysator aufgebracht ist. Mehrere Folien und Granulatpakete - das Granulat wird von Drahtnetzen zu Paketen zusammengehalten - sind vertikal und parallel zueinander in Blechgehäusen angeordnet. Das Wasserstoff/Luftgemisch tritt an der Unterseite in die Gehäuse ein. An den katalytisch be- schichteten Oberflächen setzt die Reaktion ein. Das Gemisch bzw. die Reaktionsprodukte überströmen die Oberflächen infolge des entstehenden thermischen Auftriebs .Both thermal and catalytic recombiners have been developed to remove the hydrogen generated during normal operation and in the event of an accident, which recombine the hydrogen with the oxygen in the air in water vapor. Preference is given to catalytic systems which work passively, ie self-starting and without an external energy supply, to ensure availability during an incident. There are two types of recombiner, both metallic plates or foils and highly porous granules, to which platinum or palladium is applied as a catalyst, being used as substrates. Several foils and pellet packages - the pellets are held together by wire nets to form packages - are arranged vertically and parallel to each other in sheet metal housings. The hydrogen / air mixture enters the housing at the bottom. The reaction starts on the catalytically coated surfaces. The mixture or the reaction products flow over the surfaces as a result of the thermal buoyancy that arises.
Die Abfuhr der Reaktionswärme aus den Systemen ist grund- sätzlich problematisch. Sie erfolgt fast ausschließlich infolge Konvektion von den festen Oberflächen an die vorbeiströmenden Gase sowie Wärmestrahlung an benachbarte Strukturen. Zu große Wasserstoffmengen können zu einer Überhitzung der beschichteten Substrate führen, so daß die Zündtempera- tur erreicht oder überschritten wird und es infolgedessen zu homogenen Gasphasenreaktionen mit Deflagration bzw. Detonation kommen kann.The removal of the heat of reaction from the systems is fundamentally problematic. It takes place almost exclusively as a result of convection from the solid surfaces to the gases flowing past as well as heat radiation to neighboring structures. Excessive amounts of hydrogen can lead to overheating of the coated substrates, so that the ignition temperature is reached or exceeded and consequently homogeneous gas phase reactions with deflagration or detonation can occur.
Das technische Problem der vorliegenden Erfindung besteht daher darin, sowohl kleine als auch große Wasserstoffmengen mit dem in den Sicherheitsbehältern vorhandenen Luftsauerstoff in einem weiten Konzentrationsbereich kontrolliert umzusetzen und durch besondere Einrichtungen im Ein- und Auslauf des Rekombinators eine Entzündung des Gasgemisches mit nachfolgender Explosion zu vermeiden.The technical problem of the present invention therefore consists in the controlled implementation of both small and large amounts of hydrogen with the atmospheric oxygen present in the security containers in a wide concentration range and to avoid ignition of the gas mixture with subsequent explosion by means of special devices in the inlet and outlet of the recombiner.
Das zuvor aufgezeigte technische Problem ist erfindungsgemäß durch einen Rekombinator zum Beseitigen von Wasserstoff aus Störfallatmosphären gelöst, der ein Gehäuse aufweist, das eine Längsrichtung für eine Durchströmung vorgibt und an beiden Enden in Längsrichtung jeweils mindestens eine Öff- nung aufweist. Der Rekombinator weist weiterhin mindestens ein Katalysatorelement auf, das in dem Gehäuse angeordnet ist. Erfindungsgemäß ist innerhalb des Gehäuses an mindestens einer der Öffnungen eine Vorrichtung zum Aufteilen des Querschnittes des Gehäuses in Teilquerschnitte vorgesehen. Durch die Aufteilung in Teilquerschnitte werden in wirksamer Weise sowohl die Entstehung als auch die Ausbreitung explosionsartiger Verbrennungen unterdrückt, so daß sich die ggf. innerhalb des Rekombinators entstehenden Flammen bzw. die Detonationswellen nicht außerhalb des Rekombinators ausbreiten.The technical problem outlined above is solved according to the invention by a recombiner for removing hydrogen from accident atmospheres, which has a housing which specifies a longitudinal direction for a flow and at least one opening at both ends in the longitudinal direction. has. The recombiner also has at least one catalyst element which is arranged in the housing. According to the invention, a device for dividing the cross section of the housing into partial cross sections is provided at least one of the openings within the housing. The division into partial cross sections effectively suppresses both the formation and the spread of explosive combustions, so that the flames or the detonation waves that may arise within the recombiner do not spread outside the recombiner.
Bei einer ersten bevorzugten Ausgestaltung der vorliegenden Erfindung ist die Vorrichtung zum Aufteilen des Querschnit- tes des Gehäuses als poröse Struktur, wie beispielsweise ein Netz oder ein Lochblech, ausgebildet, wobei sich die Vorrichtung quer zur Durchströmrichtung durch das Gehäuse über im wesentlichen den gesamten Querschnitt des Gehäuses erstreckt und wobei der Durchmesser der Öffnungen der Vorrichtung zum Aufteilen des Querschnittes des Gehäuses kleiner als ein vorgegebener Löschabstand ist. Eine derartige Vorrichtung zum Aufteilen des Querschnittes des Gehäuses kann auch als Flammenrückschlagsperre bezeichnet werden.In a first preferred embodiment of the present invention, the device for dividing the cross section of the housing is designed as a porous structure, such as a mesh or a perforated plate, the device extending transversely to the direction of flow through the housing over essentially the entire cross section of the housing Housing extends and wherein the diameter of the openings of the device for dividing the cross section of the housing is smaller than a predetermined quenching distance. Such a device for dividing the cross section of the housing can also be referred to as a flame flashback.
Eine Flammenrückschlagsperre hat die Aufgabe, die von der Flamme erzeugte Wärme schnell zu verteilen und abzuführen und somit eine durch die Flamme erzeugte explosionsartige Ausbreitung der Detonation zu verhindern. Denn sollte es trotz aller Vorsorgemaßnahmen, die innerhalb des Rekombina- tors getroffen worden sind, doch nach einer Entzündung des wasserstoffreichen Gasgemisches an einer katalytisch wirkenden Oberfläche zu einer anschließenden homogenen Gasphasenreaktion kommen, wird die während der Verbrennung (Deflagration) entstehende Wärme schnell und sicher von der an der Öffnung des Gehäuses des Rekombinators angeordneten Vorrich- tung zum Aufteilen des Querschnittes des Gehäuses, der Flammenrückschlagsperre, abgeführt.A flame non-return valve has the task of quickly distributing and dissipating the heat generated by the flame and thus preventing an explosion-like expansion of the detonation caused by the flame. If, despite all the precautionary measures that have been taken within the recombiner, an ignition of the hydrogen-rich gas mixture on a catalytically active surface leads to a subsequent homogeneous gas phase reaction, the heat generated during the combustion (deflagration) will quickly and safely dissipate the device arranged at the opening of the housing of the recombiner device for dividing the cross section of the housing, the flame flashback, dissipated.
Somit wird der Rekombinator nicht zu einer Quelle für wei- terreichende Verbrennungen oder sogar Detonationen innerhalb des Containments. Die Öffnungen in der porösen Struktur sind dabei so bemessen, daß sie eine kritische Größe, den sogenannten "Löschabstand", nicht überschreiten. Dieser Löschabstand ist abhängig vom Zustand des brennbaren oder explo- siven Gasgemisches und wird für den jeweiligen Rekombinator- typ und dessen Anwendungsbereich bestimmt. Um dabei die Wirkungsweise der Flammenrückschlagsperre weiter zu verbessern, wird in bevorzugter Weise die poröse Struktur der Vorrichtung zum Aufteilen des Querschnittes des Gehäuses durch eine Kühlvorrichtung gekühlt.Thus, the recombiner does not become a source for extensive burns or even detonations within the containment. The openings in the porous structure are dimensioned so that they do not exceed a critical size, the so-called "extinguishing distance". This extinguishing distance depends on the condition of the combustible or explosive gas mixture and is determined for the respective type of recombiner and its area of application. In order to further improve the mode of operation of the flame non-return valve, the porous structure of the device for dividing the cross section of the housing is preferably cooled by a cooling device.
Bei einer zweiten bevorzugten Ausgestaltung der vorliegenden Erfindung weist die Vorrichtung zum Aufteilen des Querschnittes des Gehäuses in Teilquerschnitte Platten oder Fo- lien auf, die innerhalb des Gehäuses angeordnet sind, sich längs der Durchströmrichtung des Gehäuses erstrecken und das Volumen des Gehäuses zumindest im Bereich der Öffnungen in Teilvolumina aufteilt. Dieser Ausgestaltung liegt die Erkenntnis zugrunde, daß sich Detonationen nur in Geometrien fortpflanzen, deren Abmessungen größer als die Abmessungen von sogenannten "Detonationszellen" sind. Die Größe einer Detonationszelle ist abhängig von der Gemischkonzentration sowie dem Druck und der Temperatur, die in dem Gasgemisch vorliegen. Für unterschiedliche Geometrien, z. B. Spalte oder Rohre, aus denen Detonationswellen in einen Raum austreten können, lassen sich kritische Abmessungen als ein Vielfaches der Detonationszelle bestimmen. Bei Unterschreiten dieser Größe wird ein Austritt der Detonationen verhindert. Für Rohrgeometrien ergibt sich z. B. eine Kennzahl von 13, für Rechteckgeometrien eine von 3. Wenn also in einem Rohr eine Detonation ausgelöst wird, kann die Welle nicht aus dem Rohr in die freie Umgebung gelangen, wenn der Rohrdurchmesser höchstens 13 mal größer als die Detonationszelle ist. Für einen Rechteckkanal darf die kleinere Kantenlänge höchstens 3 mal größer als die genannte Zelle sein. In einem Rechteckkanal pflanzt sich eine Welle dann nicht fort, wenn die kleinere Kantenlänge kleiner als ein Drittel der Größe der Detonationszelle ist. Die Platten oder Folien der Vorrichtung zum Aufteilen des Querschnittes des Gehäuses sind daher so ausgebildet, daß ihr Abstand kleiner als ein Drit- tel der Größe der Detonationszelle zur Verhinderung der Fortpflanzung einer Detonation innerhalb der Kanäle und kleiner als 3 zur Verhinderung des Austretens der Detonationswelle aus dem Kanal in das freie Volumen ist. Die Größe der Zelle ist abhängig von den Zustandsgrößen des Gasgemi- sches . Die zuvor beschriebene Vorrichtung zum Aufteilen des Querschnittes des Gehäuses in Teilquerschnitte kann auch als Detonationssperre bezeichnet werden.In a second preferred embodiment of the present invention, the device for dividing the cross section of the housing into partial cross sections has plates or foils which are arranged within the housing, extend along the flow direction of the housing and the volume of the housing at least in the region of the openings divided into partial volumes. This embodiment is based on the knowledge that detonations only propagate in geometries whose dimensions are larger than the dimensions of so-called "detonation cells". The size of a detonation cell depends on the mixture concentration and the pressure and temperature that are present in the gas mixture. For different geometries, e.g. B. gaps or pipes from which detonation waves can emerge in a room, critical dimensions can be determined as a multiple of the detonation cell. If this size is undershot, the detonations are prevented from escaping. For pipe geometries, z. B. a key figure of 13, for rectangular geometries one of 3. So if a detonation is triggered in a pipe, the shaft cannot get out of the pipe into the free environment if the pipe diameter is at most 13 times larger than the detonation cell. For a rectangular channel, the smaller edge length may not be more than 3 times larger than the cell mentioned. A wave does not propagate in a rectangular channel if the smaller edge length is less than a third of the size of the detonation cell. The plates or foils of the device for dividing the cross section of the housing are therefore designed such that their spacing is less than a third of the size of the detonation cell to prevent the propagation of a detonation within the channels and less than 3 to prevent the detonation wave from escaping the channel into the free volume. The size of the cell depends on the state variables of the gas mixture. The device described above for dividing the cross section of the housing into partial cross sections can also be referred to as a detonation barrier.
In bevorzugter Weise bilden die Platten oder Folien der Vor- richtung zum Aufteilen des Querschnittes des Gehäuses eine rechteckförmige Struktur, so daß benachbart angeordnete Strömungskanäle durch das Gehäuse des Rekombinators jeweils eine ähnliche Größe und Form aufweisen. Dabei wird insbesondere bei Verwendung dickerer Platten eine zusätzliche Stabi- lität erreicht, die gerade beim Auftreten von Detonationen verhindert, daß aufgrund der Detonationskräfte die von den Platten aufgebaute Struktur zerstört und somit die Wirkung der Detonationssperre aufgehoben wird.The plates or foils of the device for dividing the cross section of the housing preferably form a rectangular structure, so that adjacent flow channels through the housing of the recombiner each have a similar size and shape. In particular, when using thicker plates, additional stability is achieved which, especially when detonations occur, prevents the structure built up by the plates from being destroyed due to the detonation forces and thus the effect of the detonation barrier being released.
In bevorzugter Weise werden die Platten oder Folien der Vorrichtung zum Aufteilen des Querschnittes des Gehäuses in den innenliegenden Bereichen des Gehäuses mit katalytisch wirkenden Materialien beschichtet, um auch an den Oberflächen dieser Platten und Folien eine Umsetzung des Wasserstoffes im Gasgemisch zu bewirken. In bevorzugter Weise sind jedoch die Platten oder Folien im Bereich der Öffnungen an den En- den des Gehäuses nicht oder nur in geringem Umfang mit kata- lytisch wirkendem Material beschichtet, so daß in diesen Bereichen eine weitere Umsetzung des Wasserstoffes und somit eine weitere Entstehung von Wärme verhindert wird.The plates or foils of the device for dividing the cross section of the housing in the inner regions of the housing are preferably coated with catalytically active materials in order to also bring about a reaction of the hydrogen in the gas mixture on the surfaces of these plates and foils. However, the plates or foils are preferably in the area of the openings at the ends. that of the housing is not or only to a small extent coated with catalytically active material, so that a further conversion of the hydrogen and thus a further generation of heat is prevented in these areas.
Bei einer weiteren bevorzugten Ausgestaltung sind an den Enden der Teilvolumina, die von den Platten oder Folien gebildet werden, im Bereich der Öffnungen des Gehäuses Reflektoren angeordnet, die vorzugsweise in Eintrittsrichtung in das Gehäuse einen geringen Strömungswiderstand und in Austrittsrichtung aus dem Gehäuse einen höheren Strömungswiderstand aufweisen. Weiterhin erstrecken sich die Reflektoren im wesentlichen über die gesamte Breite der innerhalb des Gehäuses des Rekombinators angeordneten Platten oder Folien. Die- se Reflektoren stellen eine zusätzliche Maßnahme dar, Detonationswellen, die aus den Teilvolumina austreten, zumindest teilweise zu reflektieren und somit ein Austreten der Detonationswellen aus dem Gehäuse des Rekombinators zu verhindern.In a further preferred embodiment, reflectors are arranged at the ends of the partial volumes formed by the plates or foils in the region of the openings of the housing, which reflectors preferably have a low flow resistance in the direction of entry into the housing and a higher flow resistance in the direction of exit from the housing . Furthermore, the reflectors extend essentially over the entire width of the plates or foils arranged within the housing of the recombiner. These reflectors represent an additional measure to at least partially reflect detonation waves that emerge from the partial volumes and thus prevent the detonation waves from escaping from the housing of the recombiner.
Die vorgenannten sowie die beanspruchten und in den Ausfüh- rungsbeispielen beschriebenen erfindungsgemäß zu verwendenden Bauteile unterliegen in ihrer Größe, Form, Gestaltung, Materialauswahl und technischen Konzeption keinen besonderen Ausnahmebedingungen, so daß die in dem Anwendungsgebiet bekannten Auswahlkriterien uneingeschränkt Anwendung finden können. Weitere Einzelheiten, Merkmale und Vorteile des Gegenstandes der Erfindung ergeben sich aus der nachfolgenden Beschreibung der zugehörigen Zeichnung, in der - beispiel- haft - bevorzugte Ausführungsformen des erfindungsgemäßen Rekombinators dargestellt sind. In der Zeichnung zeigen:The size, shape, design, choice of material and technical concept of the above-mentioned components as well as the components to be used according to the invention described in the exemplary embodiments are not subject to any special exceptional conditions, so that the selection criteria known in the field of application can be used without restriction. Further details, features and advantages of the subject matter of the invention result from the following description of the accompanying drawing, in which - by way of example - preferred embodiments of the recombiner according to the invention are shown. The drawing shows:
Fig. 1 ein erstes Ausführungsbeispiel des erfindungsgemäßen Rekombinators im Querschnitt und Fig. 2 ein zweites Ausführungsbeispiel des erfindungsgemäßen Rekombinators im Querschnitt.Fig. 1 shows a first embodiment of the recombiner according to the invention in cross section and Fig. 2 shows a second embodiment of the recombiner according to the invention in cross section.
In Fig. 1 ist ein erstes Ausführungsbeispiel des erfindungs- gemäßen Rekombinators zum Beseitigen von Wasserstoff aus Störfallatmosphären dargestellt. Der Rekombinator weist ein Gehäuse 2 auf, das eine Längsrichtung für eine Durchströmung eines Gasgemisches aus einer Störfallatmosphäre innerhalb eines Containments eines Reaktors vorgibt. Das Gehäuse 2 weist an beiden Enden in Längsrichtung, die in Fig. 1 von unten nach oben ausgerichtet ist, jeweils eine Öffnung 4 und 6 auf. Weiterhin sind mehrere Katalysatorelemente 7 im Gehäuse 2 angeordnet, wobei es sich bei den dargestellten Katalysatorelementen 7 um durchströmte Katalysatormodule han- delt, die von dem Gasgemisch durchströmt werden und die eine Rekombination, d. h. eine Umsetzung des Wasserstoffes aus dem Gasgemisch mit innerhalb der Katalysatormodule enthaltenen katalytisch wirkenden Strukturen, bewirken. Weiterhin sind zwei verschiedene Vorrichtungen 8 zum Aufteilen des Querschnittes des Gehäuses 2 in Teilquerschnitte vorgesehen, die jeweils in der Nähe der Öffnungen 4 und 6 angeordnet und unterschiedlich ausgebildet sind, wie im folgenden beschrieben wird.1 shows a first exemplary embodiment of the recombiner according to the invention for removing hydrogen from accident atmospheres. The recombiner has a housing 2 which specifies a longitudinal direction for a gas mixture to flow through from an accident atmosphere within a containment of a reactor. The housing 2 has an opening 4 and 6 at both ends in the longitudinal direction, which is oriented from bottom to top in FIG. 1. Furthermore, a plurality of catalytic converter elements 7 are arranged in the housing 2, the catalytic converter elements 7 shown being catalytic converter modules through which the gas mixture flows and which recombine, ie. H. a reaction of the hydrogen from the gas mixture with catalytically active structures contained within the catalyst modules. Furthermore, two different devices 8 are provided for dividing the cross section of the housing 2 into partial cross sections, each of which is arranged in the vicinity of the openings 4 and 6 and is designed differently, as will be described below.
In einer ersten Ausgestaltung ist die Vorrichtung 8 als poröse Struktur 10 ausgebildet, wobei beispielsweise ein Netz oder ein Lochblech als poröse Struktur 10 verwendet werden kann. Bei dem in Fig. 1 dargestellten Ausführungsbeispiel sind an jeder Öffnung 4 bzw. 6 jeweils zwei in Durchström- richtung übereinander angeordnete Netze 10 angeordnet. Dabei erstreckt sich jedes Netz 10 quer zur Durchströmrichtung durch das Gehäuse 2 über den gesamten Querschnitt des Gehäuses 2. Weiterhin ist der Durchmesser der Öffnungen des Netzes 10 kleiner als ein vorgegebener Löschabstand. Daher wirkt jedes der Netze 10 an den Öffnungen 4 und 6 des Gehäuses 2 als Flamraensperre, in der die während der Verbrennung bzw. Deflagration des wasserstoffreichen Gasgemisches entstehende Wärme schnell und sicher abgeführt wird, so daß die Öffnungen 4 und 6 nicht zu Quellen für weiterreichende Verbrennungen oder Detonationen innerhalb des Containments wer- den.In a first embodiment, the device 8 is designed as a porous structure 10, wherein, for example, a mesh or a perforated plate can be used as the porous structure 10. In the exemplary embodiment shown in FIG. 1, two nets 10 arranged one above the other in the flow direction are arranged at each opening 4 or 6. Each net 10 extends transversely to the direction of flow through the housing 2 over the entire cross-section of the housing 2. Furthermore, the diameter of the openings of the net 10 is smaller than a predetermined quenching distance. Therefore, each of the nets 10 acts at the openings 4 and 6 of the housing 2 as a flame barrier, in which the during combustion or deflagration of the hydrogen-rich gas mixture, the heat generated is dissipated quickly and safely, so that the openings 4 and 6 do not become sources of further-reaching burns or detonations within the containment.
Dabei ist die kritische Größe, der "Löschabstand", abhängig vom Zustand des brennbaren oder explosiven Gasgemisches. Damit die Wärme in ausreichender Form von dem Netz 10 abge- führt werden kann, sind die in Fig. 1 dargestellten Netze 10 mit der massiven Wand des Gehäuses 2 verbunden.The critical size, the "extinguishing distance", depends on the condition of the flammable or explosive gas mixture. So that the heat can be dissipated from the network 10 in sufficient form, the networks 10 shown in FIG. 1 are connected to the solid wall of the housing 2.
In einer weiteren Ausgestaltung der Vorrichtung 8 zum Aufteilen des Querschnittes des Gehäuses 2 sind Platten 12 vor- gesehen, die innerhalb des Gehäuses 2 angeordnet sind und sich längs der Durchströmrichtung des Gehäuses 2 erstrecken. Dabei wird das Volumen des Gehäuses 2 durchgängig und somit auch im Bereich der Öffnungen 4 und 6 in Teilvolumina 14 aufgeteilt. Dabei ist der Platten- oder Folienabstand als klei- nere Abmessung der Teilvolumina 14 so gewählt, daß er kleiner als eine vorgegebene Kennzahl ist, die ein Vielfaches der Detonationszellen ist und einen für die Geometrie der Teilvolumina 14 und für die Zustandsgrößen des Gasgemisches charakteristischen Wert darstellt. Durch die Platten 12 wird somit das gesamte Volumen des Gehäuses 2, dessen Abmessungen größer als die vorgegebene Kennzahl sind, in ausreichend kleine Teilvolumina 14 aufgeteilt. Insgesamt kann die Ausgestaltung der Vorrichtung 8 zum Aufteilen des Querschnittes des Gehäuses 2 in Form von Platten 12 als Detonationssperre bezeichnet werden.In a further embodiment of the device 8 for dividing the cross section of the housing 2, plates 12 are provided which are arranged within the housing 2 and extend along the flow direction of the housing 2. The volume of the housing 2 is continuous and thus also divided into partial volumes 14 in the area of the openings 4 and 6. The plate or film spacing is chosen as the smaller dimension of the partial volumes 14 so that it is smaller than a predetermined characteristic number, which is a multiple of the detonation cells and represents a value characteristic of the geometry of the partial volumes 14 and of the state variables of the gas mixture . The entire volume of the housing 2, the dimensions of which are larger than the predetermined characteristic number, is thus divided into sufficiently small partial volumes 14 by the plates 12. Overall, the design of the device 8 for dividing the cross section of the housing 2 in the form of plates 12 can be referred to as a detonation barrier.
Bei dem in Fig. 1 dargestellten Ausführungsbeispiel sind dieIn the embodiment shown in Fig. 1 are the
Platten oder Folien 12 so ausgebildet, daß sie bis an diePlates or foils 12 formed so that they are up to
Netze 10 heranreichen und mit diesen wärmeleitend verbunden sind. Dadurch wird die im Inneren des Gehäuses 2 entstandene Wärme über die Platten oder Folien 12 und die Netze 10 an das Gehäuse 2 oder die umgebenden Gase abgeleitet.Reach networks 10 and are connected to them in a heat-conducting manner. This creates the inside of the housing 2 Heat is dissipated via the plates or foils 12 and the networks 10 to the housing 2 or the surrounding gases.
In Fig. 2 ist ein zweites Ausführungsbeispiel des erfin- dungsgemäßen Rekombinators dargestellt. Auch bei diesem Ausführungsbeispiel weist das Gehäuse 2 des Rekombinators an den Öffnungen 4 und 6 die beiden zuvor beschriebenen Ausgestaltungen der Vorrichtung 8 zum Aufteilen des Querschnittes des Gehäuses in Teilquerschnitte auf. In Fig. 2 ist darge- stellt, daß anstelle der in Fig. 1 gezeigten Netze die poröse Struktur als Lochblech 10 ausgebildet ist, das jeweils an den Öffnungen 4 und 6 mit der Wand des Gehäuses 2 verbunden ist. Da ein Lochblech massiver als ein Netz ausgebildet ist, sind Stabilität und Wärmekapazität gegenüber einem Netz größer, so daß die Wärmeaufnahme und -ableitung effizienter durchgeführt werden kann. Dabei muß jedoch in Kauf genommen werden, daß die Anzahl der Öffnungen geringer als bei einem Netz ist.2 shows a second exemplary embodiment of the recombiner according to the invention. In this exemplary embodiment, too, the housing 2 of the recombiner has the two previously described configurations of the device 8 for dividing the cross section of the housing into partial cross sections at the openings 4 and 6. FIG. 2 shows that instead of the nets shown in FIG. 1, the porous structure is designed as a perforated plate 10, which is connected to the wall of the housing 2 at the openings 4 and 6. Since a perforated plate is made more solid than a network, stability and heat capacity are greater compared to a network, so that the heat absorption and dissipation can be carried out more efficiently. However, it must be accepted that the number of openings is less than that of a network.
Weiterhin ist die zweite Ausgestaltung der Vorrichtung 8 zum Aufteilen des Querschnittes des Gehäuses 2 in Teilquerschnitte in Form der Platten 12 auch bei dem in Fig. 2 dargestellten Ausführungsbeispiel im Gehäuse 2 angeordnet. Im Gegensatz zu dem in Fig. 1 dargestellten Ausführungsbeispiel sind die Katalysatorelemente 7 als flächige Beschichtungen der Platten 12 mit Katalysatormaterial ausgebildet, so daß die katalytische Rekombination an den Oberflächen der Platten 12 stattfindet. Wie in Fig. 2 dargestellt ist, befindet sich die katalytische Beschichtung in den Bereichen 12A der Plat- ten 12, die auf den inneren Bereich des Innenraums des Gehäuses 2 beschränkt ist. Die den Öffnungen 4 und 6 zugewandten Bereiche 12B der Platten 12 sind dagegen nicht mit einem katalytischen Material beschichtet, damit je nach Durchströmrichtung an den Austrittsbereichen der Öffnungen 4 bzw. 6 keine weitere Rekombination mit Wärmeentwicklung stattfindet und durch eine an den unbeschichteten Abschnitten 12B stattfindende Kühlung eine auftretende Flammenentwicklung unterdrückt oder zumindest verringert wird.Furthermore, the second embodiment of the device 8 for dividing the cross section of the housing 2 into partial cross sections in the form of the plates 12 is also arranged in the housing 2 in the exemplary embodiment shown in FIG. 2. In contrast to the exemplary embodiment shown in FIG. 1, the catalyst elements 7 are designed as flat coatings of the plates 12 with catalyst material, so that the catalytic recombination takes place on the surfaces of the plates 12. As shown in FIG. 2, the catalytic coating is located in the areas 12A of the plates 12, which is limited to the inner area of the interior of the housing 2. The areas 12B of the plates 12 facing the openings 4 and 6, on the other hand, are not coated with a catalytic material, so that, depending on the direction of flow, no further recombination with heat development takes place at the outlet areas of the openings 4 or 6 and due to the uncoated sections 12B occurring cooling is suppressed or at least reduced an occurring flame development.
Als weitere Maßnahme zur Verhinderung des Austretens von De- tonationswellen aus dem Gehäuse 2 des Rekombinators sind an den Enden der Teilvolumina 14 im Bereich der Öffnungen 4 und 6 des Gehäuses 2 Reflektoren 16 angeordnet. Diese Reflektoren weisen dabei eine Form in Längsrichtung auf, die in Eintrittsrichtung in das Gehäuse 2 einen geringen Strömungswi- derstand und in Austrittsrichtung aus dem Gehäuse 2 einen höheren Strömungswiderstand für das Gasgemisch aufweisen. Somit wird einerseits eine aus dem Inneren des Gehäuses 2 sich entlang der Teilvolumina 14 ausbreitende Detonationswelle von den Oberflächen der Reflektoren zumindest teilwei- se reflektiert. Gleichzeitig wird jedoch die normale Aus- und Einströmung des Gasgemisches in das Gehäuse 2 des Rekombinators nicht zu sehr durch die Reflektoren 14 behindert.As a further measure for preventing detonation waves from emerging from the housing 2 of the recombiner, reflectors 16 are arranged at the ends of the partial volumes 14 in the region of the openings 4 and 6 of the housing. These reflectors have a shape in the longitudinal direction which have a low flow resistance in the direction of entry into the housing 2 and a higher flow resistance for the gas mixture in the direction of exit from the housing 2. Thus, on the one hand, a detonation wave propagating from the interior of the housing 2 along the partial volumes 14 is at least partially reflected by the surfaces of the reflectors. At the same time, however, the normal outflow and inflow of the gas mixture into the housing 2 of the recombiner is not hampered too much by the reflectors 14.
Wie in Fig. 2 dargestellt ist, ist an jedem Ende eines Teil- volumens 14 ein Reflektor 16 angeordnet, der sich im wesentlichen über die gesamte Breite der innerhalb des Gehäuses 2 angeordneten Platten 12 erstreckt. Dadurch wird sichergestellt, daß jeweils möglichst der gesamte Querschnitt jedes Teilvolumens mit einem Reflektor 16 beaufschlagt ist. As shown in FIG. 2, a reflector 16 is arranged at each end of a partial volume 14 and extends essentially over the entire width of the plates 12 arranged within the housing 2. This ensures that a reflector 16 is applied to the entire cross-section of each partial volume.
BezugszeichenlisteReference list
2 Gehäuse2 housings
4 Öffnung4 opening
6 Öffnung6 opening
7 Katalysatoreleraent7 catalyst element
8 Vorrichtung zum Aufteilen des Querschnittes 10 Netz, poröse Struktur8 device for dividing the cross section 10 mesh, porous structure
12 Platten, Folien12 plates, foils
12A beschichteter Abschnitt12A coated section
12B unbeschichteter Abschnitt12B uncoated section
14 Teilvolumen14 partial volumes
16 Reflektoren 16 reflectors

Claims

Patentansprüche: Claims:
1. Rekombinator zum Beseitigen von Wasserstoff aus Störfallatmosphären mit einem Gehäuse (2), das eine Längsrichtung für eine Durchströmung vorgibt und an beiden Enden in Längsrichtung jeweils eine Öffnung (4,6) aufweist, und mit mindestens einem Katalysatorelement (7), das in dem Gehäuse (2) angeordnet ist,1. Recombiner for removing hydrogen from accident atmospheres with a housing (2) which specifies a longitudinal direction for a flow and has an opening (4, 6) at both ends in the longitudinal direction, and with at least one catalyst element (7) which in the housing (2) is arranged,
dadurch gekennzeichnet,characterized,
daß innerhalb des Gehäuses (2) an mindestens einer der Öffnungen (4,6) eine Vorrichtung (8) zum Aufteilen des Querschnittes des Gehäuses (2) in Teil- querschnitte vorgesehen ist.that a device (8) for dividing the cross-section of the housing (2) into partial cross sections is provided at least one of the openings (4, 6) within the housing (2).
2. Rekombinator nach Anspruch 1, dadurch gekennzeichnet, daß die Vorrichtung (8) als poröse Struktur (10) ausgebildet ist, wobei sich die poröse Struktur (10) quer zur Durchströmrichtung durch das Gehäuse (2) über im wesentlichen den gesamten Querschnitt des Gehäuses (2) erstreckt und wobei der Durchmesser der Öffnungen der porösen Struktur (10) kleiner als ein vorgegebener Löschabstand ist.2. Recombiner according to claim 1, characterized in that the device (8) is designed as a porous structure (10), the porous structure (10) transverse to the flow direction through the housing (2) over substantially the entire cross section of the housing (2) extends and the diameter of the openings of the porous structure (10) is smaller than a predetermined quenching distance.
3. Rekombinator nach Anspruch 2, dadruch gekennzeichnet, daß die poröse Struktur (10) als Netz oder als Lochblech ausgebildet ist.3. Recombiner according to claim 2, characterized in that the porous structure (10) is designed as a network or as a perforated plate.
4. Rekombinator nach Anspruch 2 oder 3, dadurch gekennzeichnet, daß eine Kühlvorrichtung die poröse Struktur (10) kühlt. 4. Recombiner according to claim 2 or 3, characterized in that a cooling device cools the porous structure (10).
5. Rekombinator nach Anspruch 1, dadurch gekennzeichnet, daß die Vorrichtung (8) Platten oder Folien (12) aufweist, die innerhalb des Gehäuses (2) angeordnet sind, sich längs der Durchströmrichtung des Gehäuses (2) er- strecken und das Volumen des Gehäuses (2) zumindest im5. Recombiner according to claim 1, characterized in that the device (8) has plates or foils (12) which are arranged within the housing (2), extend along the flow direction of the housing (2) and the volume of the Housing (2) at least in
Bereich der Öffnung (4,6) in Teilvolumina (14) aufteilt.Divides the area of the opening (4, 6) into partial volumes (14).
6. Rekombinator nach Anspruch 5, dadurch gekennzeichnet, daß die Abmessungen der Teilvolumina (14) kleiner als eine vorgegebene Kennzahl sind, die ein Vielfaches der Größe der Detonationszellen ist und einen für die Geometrie der Teilvolumina (14) und für die Zustandsgroßen des Gasgemisches charakteristischen Wert darstellt.6. Recombiner according to claim 5, characterized in that the dimensions of the partial volumes (14) are smaller than a predetermined characteristic number, which is a multiple of the size of the detonation cells and a characteristic of the geometry of the partial volumes (14) and for the state variables of the gas mixture Represents value.
1. Rekombinator nach Anspruch 5 oder 6 , dadurch gekennzeichnet, daß die Platten oder Folien (12) rechteckför- mige Strömungskanäle bilden.1. Recombiner according to claim 5 or 6, characterized in that the plates or foils (12) form rectangular flow channels.
8. Rekombinator nach einem der Ansprüche 5 bis 7 , dadurch gekennzeichnet, daß die Platten oder Folien (12) im Bereich der Öffnung (4,6) im wesentlichen keine kataly- tisch wirkende Beschichtung aufweisen.8. Recombiner according to one of claims 5 to 7, characterized in that the plates or films (12) in the region of the opening (4, 6) have essentially no catalytically active coating.
9. Rekombinator nach einem der Ansprüche 5 bis 8, dadurch gekennzeichnet, daß Reflektoren (16) an den Enden der Teilvolumina (14) im Bereich der Öffnungen (4,6) des Gehäuses (2) angeordnet sind.9. Recombiner according to one of claims 5 to 8, characterized in that reflectors (16) are arranged at the ends of the partial volumes (14) in the region of the openings (4, 6) of the housing (2).
10. Rekombinator nach Anspruch 9, dadurch gekennzeichnet, daß die Reflektoren (16) in Eintrittsrichtung in das Gehäuse (2) einen geringen Strömungswiderstand und in Austrittsrichtung aus dem Gehäuse ( 2 ) einen höheren Strömungswiderstand aufweisen. 10. Recombiner according to claim 9, characterized in that the reflectors (16) have a low flow resistance in the entry direction into the housing (2) and a higher flow resistance in the exit direction from the housing (2).
1. Rekombinator nach Anspruch 9 oder 10, dadurch gekennzeichnet, daß sich die Reflektoren (16) im wesentlichen über die gesamte Breite der innerhalb des Gehäuses (2) angeordneten Platten oder Folien (12) erstrecken. 1. Recombiner according to claim 9 or 10, characterized in that the reflectors (16) extend substantially over the entire width of the plates or films (12) arranged within the housing (2).
PCT/EP1999/008738 1998-11-17 1999-11-12 Recombiner for the efficient elimination of hydrogen from atmospheres created as a result of malfunctioning WO2000030123A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19852951.1 1998-11-17
DE19852951A DE19852951C2 (en) 1998-11-17 1998-11-17 Recombiner for the effective removal of hydrogen from hazardous atmospheres

Publications (1)

Publication Number Publication Date
WO2000030123A1 true WO2000030123A1 (en) 2000-05-25

Family

ID=7888054

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1999/008738 WO2000030123A1 (en) 1998-11-17 1999-11-12 Recombiner for the efficient elimination of hydrogen from atmospheres created as a result of malfunctioning

Country Status (2)

Country Link
DE (1) DE19852951C2 (en)
WO (1) WO2000030123A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6846775B1 (en) * 1998-11-17 2005-01-25 Forschungszentrum Julich Gmbh Recombinator for eliminating hydrogen from accident atmospheres
CN101437607B (en) * 2006-05-08 2011-11-16 康帕克特Gtl有限公司 Catalytic reactor comprising first and secondary flow channels arranged alternately
CN113380431A (en) * 2021-06-03 2021-09-10 哈尔滨工程大学 Hydrogen recombiner catalytic unit
CN115103718A (en) * 2020-01-30 2022-09-23 环球油品有限责任公司 Slotted plate sector

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10148926A1 (en) * 2001-10-04 2003-04-17 Forschungszentrum Juelich Gmbh Distribution structure used in low temperature fuel cells comprises a reaction zone and a feed channel running conically on the reaction zone and containing devices to deviate the flow
DE10150385B4 (en) * 2001-10-11 2005-12-08 Ballard Power Systems Ag The fuel cell system
NL1022756C2 (en) * 2003-02-21 2004-08-24 Stichting Tech Wetenschapp Microreactor for rapid parallel testing of catalysts.
BRPI0711443A2 (en) 2006-05-08 2011-11-01 Compactgtl Plc compact catalytic reactor, methods of performing combustion, and performing a rapid reaction on it, and of controlling the thermal gradient in a catalytic reactor
DE102019102690A1 (en) 2018-02-16 2019-08-22 Dieter Seeliger Method and arrangement for heat recovery by means of cavitation and their combination with other excitation methods

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3924553A1 (en) * 1989-07-25 1991-01-31 Wiesemes Johannes ADDITIONAL DEVICE FOR THE REMOVAL OF FLAMMABLE GAS MIXTURES
US5167908A (en) * 1990-01-08 1992-12-01 Gesellschaft Fur Reaktorsicherheit (Grs) Device for recombination of hydrogen and oxygen
US5230859A (en) * 1988-06-14 1993-07-27 Johannes Wiesemes Process and device for removing flammable gas mixtures in a gas space
US5473646A (en) * 1990-05-11 1995-12-05 Siemens Aktiengesellschaft Device for the recombination of hydrogen and oxygen and nuclear power plant using the device
US5592521A (en) * 1991-07-29 1997-01-07 Siemens Aktiengesellschaft Process and device for recombining and/or igniting hydrogen contained in an H2 -air-steam mixture, preferably for nuclear power stations
DE19636557A1 (en) * 1996-09-09 1998-03-12 Siemens Ag Catalyst system and recombination device for the recombination of hydrogen and oxygen, in particular for a nuclear power plant
DE19704608C1 (en) * 1997-02-07 1998-06-10 Siemens Ag Convection-driven hydrogen recombination chimney within nuclear power plant containment

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4780271A (en) * 1985-10-02 1988-10-25 Westinghouse Electric Corp. Process and apparatus for burning gases containing hydrogen and for cooling resulting combustion gases
DE3727207A1 (en) * 1987-08-14 1989-02-23 Siemens Ag Device for recombining hydrogen and oxygen
DE9303209U1 (en) * 1993-03-05 1993-07-15 Kernforschungszentrum Karlsruhe Gmbh, 7500 Karlsruhe, De

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5230859A (en) * 1988-06-14 1993-07-27 Johannes Wiesemes Process and device for removing flammable gas mixtures in a gas space
DE3924553A1 (en) * 1989-07-25 1991-01-31 Wiesemes Johannes ADDITIONAL DEVICE FOR THE REMOVAL OF FLAMMABLE GAS MIXTURES
US5167908A (en) * 1990-01-08 1992-12-01 Gesellschaft Fur Reaktorsicherheit (Grs) Device for recombination of hydrogen and oxygen
US5473646A (en) * 1990-05-11 1995-12-05 Siemens Aktiengesellschaft Device for the recombination of hydrogen and oxygen and nuclear power plant using the device
US5592521A (en) * 1991-07-29 1997-01-07 Siemens Aktiengesellschaft Process and device for recombining and/or igniting hydrogen contained in an H2 -air-steam mixture, preferably for nuclear power stations
DE19636557A1 (en) * 1996-09-09 1998-03-12 Siemens Ag Catalyst system and recombination device for the recombination of hydrogen and oxygen, in particular for a nuclear power plant
DE19704608C1 (en) * 1997-02-07 1998-06-10 Siemens Ag Convection-driven hydrogen recombination chimney within nuclear power plant containment

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6846775B1 (en) * 1998-11-17 2005-01-25 Forschungszentrum Julich Gmbh Recombinator for eliminating hydrogen from accident atmospheres
CN101437607B (en) * 2006-05-08 2011-11-16 康帕克特Gtl有限公司 Catalytic reactor comprising first and secondary flow channels arranged alternately
CN115103718A (en) * 2020-01-30 2022-09-23 环球油品有限责任公司 Slotted plate sector
CN113380431A (en) * 2021-06-03 2021-09-10 哈尔滨工程大学 Hydrogen recombiner catalytic unit

Also Published As

Publication number Publication date
DE19852951C2 (en) 2002-07-11
DE19852951A1 (en) 2000-05-18

Similar Documents

Publication Publication Date Title
DE19636557B4 (en) Use of a catalyst system and recombination device for the recombination of hydrogen and oxygen, in particular for a nuclear power plant
EP0596964B1 (en) Process and device for recombining and/or igniting hydrogen contained in a h 2-air-vapour mixture, especially for nuclear power stations
EP1166278B1 (en) Recombination device
EP0958579B1 (en) Device for recombining hydrogen in a gas mixture
DE102007059827B3 (en) Nuclear plant safety system has multiple catalytic recombination elements, where every recombination element releases recombination reaction with hydrogen guided against gas flow with oxygen
WO2009074228A2 (en) Recombiner element
WO2000030123A1 (en) Recombiner for the efficient elimination of hydrogen from atmospheres created as a result of malfunctioning
EP0640990B1 (en) Device for passively rendering inert the gas mixture in the security containment of nuclear power plant
DE2637111A1 (en) PROCESS FOR CATALYTICALLY ASSISTED THERMAL COMBUSTION OF A FUEL-AIR MIXTURE AND CATALYST DEVICE FOR CARRYING OUT THE PROCESS
EP1131825B1 (en) Catalyst element for a recombiner for the efficient elimination of hydrogen from atmospheres created as a result of malfunctioning
DE202009009405U1 (en) Passive autocatalytic hydrogen and oxygen recombinator for operation in a high hydrogen environment
DE19708738C1 (en) Device for removing hydrogen
EP0923776B1 (en) Process and device for initiating a hydrogen-oxygen reaction in a reactor safety container
EP1131826A2 (en) Recombiner for effectively removing hydrogen from air contaminated by accidents
DE19919268C2 (en) Recombiner for removing hydrogen
DE19846058C1 (en) Device for removing hydrogen
EP1224668A1 (en) Device for the removal of hydrogen from gas mixtures flowing through pipes pipes
EP1314166B1 (en) Recombiner with a regulated reaction temperature
DE102014015948B4 (en) Sicherheitszündvorrichtung
DE10223328A1 (en) Gas converter with activity-adjusted catalyst system
WO1991001559A1 (en) Improved device for eliminating combustible gaseous mixtures

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
122 Ep: pct application non-entry in european phase