EP1251314A2 - Catalytic burner - Google Patents

Abstract

The burner has a catalytic structure (4) forming the walls of several adjacent channels (13) through the structure. Parts of the walls are coated with a catalyst. There are connecting apertures (14) between the inlet end and outlet end of the catalytic structure. Adjacent channels are linked through these apertures.

Description

Technical field

The invention relates to a catalytic burner, in particular for a Gas turbine plant with the features of the preamble of claim 1.

State of the art

From US 5 512 250 a catalyst structure is known which is a heat-resistant Carrier material which has the common walls of a plurality of adjacent Forms channels. These channels penetrate the catalyst structure in Longitudinal direction and allow a flow through the catalyst structure a gaseous reaction mixture. At least part of the walls are with one Coated catalyst. There are some in the known catalyst structure Channels at least partially coated on their inner walls with the catalyst, while other channels are nowhere coated with the catalyst. In this way, parallel flow channels are created, of which the one is catalytically active and the others are catalytically inactive or inert. There in no combustion reaction takes place in the inert channels, these serve for Cooling of the active channels to prevent the catalyst structure from overheating to avoid.

From US 5 248 251 a catalyst structure is known, the support material is coated with a catalyst so that there is a gradient in the direction of flow for the reactivity of the catalyst structure. This reactivity gradient is designed so that the catalyst structure has the highest activity at the inlet has and has the least activity at its outlet, the activity decreases continuously or gradually in the direction of flow. Due to the high Catalytic activity at the inlet of the catalyst structure can cause the ignition temperature for the introduced reaction mixture can be reduced, which reduces the effort for measures to increase the temperature of the reaction mixture upstream the catalyst structure becomes smaller. Through the reactivity gradient Temperature peaks in the catalyst structure can be avoided. As a carrier material this catalyst structure becomes metallic or ceramic Monolith used.

A catalyst structure is known from US Pat. No. 6,015,285 in which the catalyst layer, which is applied to the carrier material, a diffusion barrier layer is applied to the catalytic effect of the catalyst to reduce. This measure is also intended to overheat the catalyst structure prevent, which arises especially when the catalytic reaction is sufficient, trigger a homogeneous gas phase reaction within the catalyst structure.

US 5 850 731 shows a burner for a gas turbine with a conventional one first combustion zone, one of these downstream catalytic second combustion zone and one of these downstream conventional third firing zones. at medium burner loads will be upstream of the catalytic second combustion zone Fuel mixed into the exhaust gases of the conventional first combustion zone Increase burner performance.

A structured packing unit is known from WO 99/34911, which is used in systems is used for fluid contacting. Such systems are, for example a distillation tower or a single or multiple mixer. The Packing unit can be used in a catalytic still be formed catalytically. The packing unit is made of right-angled Constructed of sheet material and has a large number of parallel, linear channels that have a rectangular, in particular square, cross-section exhibit. Vortex generators or turbulators are arranged in the channels, which cause the flow to swirl. These vortex generators form openings between adjacent channels and thereby enable one fluidic connection between the channels. In this way it happens too a flow mixture between adjacent channels. With a special one Embodiment of this packing unit can also be through a porous Material made of metal fibers (fiber tissue) and with a catalyst be coated. The catalyst layer has a through the fiber fabric very large surface area, which increases its activity. Through integration a catalyst in the packing unit can e.g. after distillation and after mixing the individual fluids, in particular a liquid and a gas, a chemical reaction in the mixture take place or is initiated become.

A further structured packing unit is known from WO 99/62629, at of which the channels are formed from a porous material, this being porous Material has turbulators or turbulence generators that are essentially attached to a liquid flow through the entire surface of the packing unit enable the pores of the porous material.

Catalytically operating burners with a catalyst structure are used, for example, in the combustion of fossil fuels, for example methane gas, in particular when minimal NO _x emissions are to be achieved. Catalytically operating burners can form part of a gas turbine system and are used there to generate hot combustion exhaust gases, which are used to drive a turbine to drive a generator.

The main problems with this type of catalytic combustion are on the one hand in the relatively high ignition temperature of the gaseous reaction mixture, e.g. on Air / fuel mixture. To achieve this high ignition temperature can be a catalyst with high activity in the inlet region of the catalyst structure to be ordered. Alternatively, the temperature of the reaction mixture upstream of the catalyst structure, e.g. with an additional burner. On the other hand, there is a risk of the catalyst structure overheating, especially if there is still a homogeneous structure within the catalyst structure Forms gas phase reaction. Under a "homogeneous gas phase reaction" becomes the independently occurring combustion reaction of the reaction mixture understood that no longer requires a catalyst to run. On Another problem with the operation of a catalytic burner is therein seen that in a so-called "burnout zone", which is downstream of the catalyst structure is arranged, there is insufficient turbulence in the flow of the reaction mixture prevails, so that adequate combustion as well minimal CO emissions within a reasonable dwell time Burnout zone can only be realized with a relatively large or long burnout zone are. Other problems can arise from the fact that in the individual channels the catalytic structure the catalytic reactions or conversions run differently, so that at the outlet of the catalyst structure in the outflowing Mixture no homogeneous reaction state along the flow cross section prevails.

Presentation of the invention

The invention seeks to remedy this. The invention as set out in the claims is concerned with the problem for a catalytic worker Burner of the type mentioned to specify an embodiment which enables improved catalytic combustion.

According to the invention, this problem is solved by a catalyst structure with the Features of claim 1 solved.

The invention is based on the general idea of adjacent channels of To connect the catalyst structure to one another through connection openings, see above that a flow exchange between these channels is made possible. By this measure becomes a mixture of the gas flows of the individual channels enables, with the result that possibly developing different Reaction states within the channels over the cross section of the catalyst structure balance so that at the outlet of the catalyst structure a relative homogeneous reaction state exists over the entire flow cross-section. This improvement can be followed by a catalyst structure Burnout zone can be made shorter.

In a further development of the burner, at least one of the connection openings can Flow guide means can be assigned, which at least part of the flow of a channel into one communicating therewith through the connection opening redirect adjacent channel. These flow guidance means thus support the flow exchange between each other through the connection opening connected channels.

In another embodiment, at least one of the connection openings can be in the region a turbulator can be arranged. Such a turbulator is raining a flow coming into contact with it to generate eddies, whereby form turbulence in the flow downstream of the turbulator. In this way receives the flow direction of the reaction mixture directional components that transversely to the longitudinal direction of the catalyst structure or transversely to the longitudinal extent the channels are directed. This creates a flow exchange between the Channels supported by the connection openings.

The flow guide means of the connection openings can preferably be used as turbulators be trained.

A flow exchange through the connection openings can also thereby be improved that the channels at least partially have a tortuous flow path form through the catalyst structure.

According to a further embodiment, the coating of the walls be designed with the catalyst so that some of the channels are catalytically active while other channels are catalytically inactive or inert. Through this measure overheating of the catalytically active walls is avoided.

It is particularly advantageous to coat the walls with the catalyst so that at least some of the channels flow at least in the direction of flow a catalytically active zone and at least one catalytically inactive or have an inert zone. With this measure, for example, the reaction state the reaction mixture, e.g. a fuel / air mixture, along the catalyst structure are controlled. This can cause the combustion reaction achieve a higher efficiency.

A special embodiment results from the fact that the coating of the Walls with the catalyst is designed so that at least some of the channels in Flow direction have several active zones, their activities are different are trained. This measure also enables targeted adjustment the desired reaction states along the catalyst structure.

According to a special embodiment, at least a part of the the catalyst coated carrier material consist of a porous material. In this embodiment, the catalyst is relatively large Surface and can be particularly active. This has to As a result, the ignition temperature of the reaction mixture decreases. Here it is also possible to design the pores of the porous material so that they Pores serve as connection openings between adjacent channels.

A particularly high catalytic activity can be achieved if at least a part of the support material coated with the catalyst from a There is fiber tissue. Such a fiber fabric has a particularly large one Surface that is catalyzed with a low ignition temperature for the reaction mixture results. Embodiments of such a fiber fabric are described, for example, in WO 99/62629 and are by this reference is encompassed by the present invention.

A particular advantage of a carrier material formed from a fiber fabric consists in the combination of a low heat storage capacity in combination with good thermal conductivity. Because of these characteristics, it arises on the carrier material a uniform temperature distribution, for example temperature peaks avoids. Similar advantages can be achieved if instead of a fiber fabric a relatively thin metal foil is used as the carrier material.

So that there is no homogeneous gas phase reaction within the catalyst structure forms the residence time of the reaction mixture in the catalyst structure do not exceed a maximum. This means that on average a certain one Flow speed must prevail, which results from the pressure loss results in the flow through the catalyst structure. To this pressure loss In a further development, those arranged in the channels can be influenced Turbulators are distributed along the catalyst structure so that the Catalyst structure in the flow direction at least one with the turbulators equipped zone and at least one not equipped with the turbulators Zone.

Preferably, one of the at least one equipped with the turbulators Zones have the outlet end of the catalyst structure. Through this measure it is ensured that at the outlet of the catalyst structure, that is, at the Transition into the burnout zone of the burner a strong mixing of the partial flows emerging from the individual channels is achieved. This strong mix supports the formation of the homogeneous gas phase reaction and reduces the flow rate, which increases the length of stay in the burnout zone elevated. This is to achieve a short construction for the burnout zone he wishes.

The zone having the outlet end is preferably the catalyst structure formed catalytically inactive or inert to the catalyst structure at this point to avoid overheating.

In a further development, one of the at least one equipped with the turbulators should Zones have the inlet end of the catalyst structure, so the same at the beginning of the catalyst structure, the channel flows are mixed support. An embodiment in which this zone is preferred is formed catalytically inactive or inert. This is how this starting zone works the catalyst structure like a static mixer for intensive mixing of the individual components of the reaction mixture, e.g. Fuel and air. Accordingly can in the burner according to the invention a conventional static Mixers are omitted or can be made smaller.

According to a preferred variant of the burner according to the invention, a the zone of the catalyst structure having the inlet end is equipped with turbulators and be formed catalytically inactive or inert, in one area at least between the inlet end and outlet end of the catalyst structure a catalytically active zone is formed, and one having the outlet end Zone of the catalyst structure equipped with turbulators and catalytic is inactive or inert. This combination of features means that a homogeneous reaction mixture is produced in the inlet zone, and here too the inlet zone works like a static mixer. Downstream of this inlet zone the catalytic reaction then takes place in order to specifically control the mixture combustion start. Intensive mixing is then carried out again in the outlet zone the already burning or reacting partial flows of the individual channels, to prepare the homogeneous gas phase reaction in the burnout chamber. It is particularly clear here that the catalyst structure is not just the actual one Catalyst function, but also the function of a static Mixer at the inlet as well as the function of a mixer or turbulator at the outlet to ensure the homogeneous gas phase reaction in the burnout chamber improve, whereby their overall length can be reduced.

In another alternative embodiment of the burner according to the invention can have a zone of the catalyst structure which has the inlet end Turbulators equipped and be catalytically highly active, with in a region between the inlet end and outlet end of the catalyst structure a zone equipped without turbulators is catalytically active, wherein a zone of the catalyst structure with turbulators which has the outlet end Is provided. In this embodiment, the combustion reaction of the incoming reaction mixture started at the inlet, the high active catalytic converter enables low ignition temperatures. Since in the downstream If no turbulators are arranged in the area, this results in a relative low pressure loss, so that relatively high flow velocities prevail. This measure reduces the risk of being inside the catalyst structure the homogeneous gas phase reaction ignites. In the outlet zone there is again an intensive mixing of the emerging individual flows achieved to improve the formation of the homogeneous gas phase reaction.

The problem underlying the invention is also solved by use solved according to claim 24.

The invention is based on the knowledge that, with appropriate adaptations, especially with regard to the choice of materials and the choice of catalyst, it is possible to use a structure such as from the above WO 99/62629 and WO 99/34911 is known in a catalytically operating Burner, especially for a gas turbine plant, as a catalyst structure to use.

Further important features and advantages of the invention result from the subclaims, from the drawings and from the associated description of the figures based on the drawings.

Brief description of the drawings

Fig. 1

eine stark vereinfachte Prinzipdarstellung eines erfindungsgemäßen Brenners bei einer ersten Ausführungsform,

Fig. 2

eine Ansicht wie in Fig. 1, jedoch bei einer zweiten Ausführungsform,

Fig. 3

eine Ansicht wie in Fig. 1, jedoch bei einer dritten Ausführungsform,

Fig. 4

eine Ansicht auf einen Ausschnitt einer Katalysator-Struktur nach der Erfindung bei einer ersten Ausführungsform,

Fig. 5

eine perspektivische Ansicht auf einen Ausschnitt der Katalysator-Struktur, jedoch bei einer zweiten Ausführungsform,

Fig. 6

eine Ansicht wie in Fig. 4, jedoch bei einer dritten Ausführungsform,

Fig. 7

eine perspektivische Ansicht auf einen Bestandteil der Katalysator-Struktur,

Fig. 8

eine Ansicht wie in Fig. 7, jedoch bei einer anderen Ausführungsform, und

Fig. 9

eine Ansicht wie in Fig. 7, jedoch bei einer weiteren Ausführungsform.

Preferred exemplary embodiments of the invention are illustrated in the drawings and are explained in more detail in the description below. Each shows schematically

Fig. 1

2 shows a greatly simplified schematic diagram of a burner according to the invention in a first embodiment,

Fig. 2

2 shows a view as in FIG. 1, but in a second embodiment,

Fig. 3

2 shows a view as in FIG. 1, but in a third embodiment,

Fig. 4

2 shows a view of a section of a catalyst structure according to the invention in a first embodiment,

Fig. 5

2 shows a perspective view of a section of the catalyst structure, but in a second embodiment,

Fig. 6

4 shows a view as in FIG. 4, but in a third embodiment,

Fig. 7

2 shows a perspective view of a component of the catalyst structure,

Fig. 8

a view as in Fig. 7, but in another embodiment, and

Fig. 9

a view as in Fig. 7, but in a further embodiment.

Ways of Carrying Out the Invention

According to FIGS. 1 to 3, a burner 1 according to the invention has a fuel injection device 2, which injects a fuel into an oxidant containing gas flow 3 injected. That symbolized here by an arrow Gas flow 3 can be formed, for example, by an air flow his. Methane can also be injected as fuel. The fuel injector 2 can be designed here as a so-called "venturi injector".

Downstream of the fuel injection device 2, the burner 1 contains a catalyst structure 4, which is symbolized here by a rectangular frame. This Catalyst structure 4 is from the fuel / gas mixture or reaction mixture through which a catalyst is arranged inside the catalyst structure 4 is that initiates a combustion reaction of the reaction mixture. Downstream the catalyst structure 4, a stabilization zone 5 is arranged in the burner 1, which symbolizes here by a sudden increase in cross-section of the burner 1 is. This stabilization zone 5 merges into a burnout zone 6, in which the actual combustion reaction of the reaction mixture, namely the homogeneous gas phase reaction takes place. If the burner 1 is a component a gas turbine plant, not shown, can in the burnout zone 6 hot combustion gases formed by the homogeneous gas phase reaction a downstream turbine can be supplied. Since the burner 1 initiates and / or stabilizes the combustion reaction by means of the catalyst structure 4, burner 1 works catalytically.

The catalyst structure 4 has an inlet end 7 and an outlet end 8 and, according to FIGS. 2 and 3, can be subdivided or divided into several zones 9 which follow one another in the flow direction. An inlet zone 9 _I comprises the inlet end 7, while an outlet zone 9 _{III contains} the outlet end 8. A central zone 9 _{II is} formed between inlet end 7 and outlet end 8, which in turn can be divided into several partial zones 9 _IIa to 9 _IIc or 9 _IId . The type and number of subdivisions is given here purely by way of example and without restricting the generality.

Fig. 4 shows a section of the catalyst structure 4, the direction of view runs parallel to a flow direction with which the reaction mixture in the Catalyst structure 4 occurs. 4 there is a carrier material 10, from which the catalyst structure 4 is made up of several layers one Material web 11. In the detail shown in FIG. 4, three such layers are made Material webs 11 shown. The material webs 11 are each zigzag-shaped here folded, with apex lines 12 of the individual folds in such material webs 11, which is transverse to the direction of flow, corresponding to Fig. 4 in vertical Direction, are adjacent, are oriented differently. 4 are the Vertex lines 12 of the upper and lower material webs 11 are oriented such that they move away from a vertical axis towards the right. The difference the apex lines 12 of the middle material web 11 are oriented so that they move away from a vertical axis towards the left. The adjacent material webs 11 in the vertical axis lie on the intersecting apex lines 12 to each other. Between adjacent to each other Layers 11 are formed more or less tortuous channels 13, which allow the flow through the catalyst structure 4. The material webs 11 form the walls of these channels 13.

According to the invention, connection openings 14 are provided in these walls, through which adjacent channels 13 communicate with each other. By this connection openings 14 can thus be mixed in the individual Channels 13 guided flows take place. Different degrees of conversion or reaction states that form in the different channels 13 can be by the flow exchange between the channels 13 in essentially balanced. The manufactured by the special design of the channels 13 winding flow paths supported by the catalyst structure 4 the flow exchange through the connection openings 14.

5 shows a larger section of the catalyst structure 4, whose carrier material 10 also consists of several layers of the material webs11 is constructed. 5, however, is only a section with four material webs 11 played. In Fig. 5 is a flow direction 15, in Fig. 4 with the viewing direction coincides, represented by an arrow. Cut the apex lines 12 in the special embodiment shown here, the flow direction 15 with an angle of about 45 °. The adjacent crest lines 12 Adjacent material webs 11 are then approximately perpendicular to one another.

Instead of zigzag folded material webs 11 can for the layers also triangular or rectangular folded or corrugated material webs be used.

6 also shows a section of the catalyst structure 4 in which the support material 10 in contrast to the embodiments of FIGS. 4 and 5 not from several material webs, but from a multi-fold material web 16 exists. The apex lines 12 of the folds of this material web 16 can doing e.g. run in the longitudinal direction of the catalyst structure 4, in particular parallel to the flow direction 15. Between successive apex lines 12 the material web 16 has flat areas which form flat wall sections 17, that run parallel to each other. Between adjacent wall sections 17 the channels 13 are formed. In these flat wall sections 17 are the Connection openings 14 are formed through which the adjacent channels 13 communicate with each other.

As material for the material web 16 according to FIG. 6 or for the material web 11 4 and 5, for example, one built on metallic fibers Serve fiber tissue, which in the catalytically active sections with a corresponding catalyst is coated. It is also possible to use the material webs 11 and 16 to be formed from a relatively thin metal foil. These materials are characterized by a high thermal conductivity and a low one Heat storage capacity because the combination of these properties into one uniform temperature distribution within the catalyst structure 4 leads and thus temperature peaks and overheating and especially initiation prevent a homogeneous gas phase reaction within the catalyst structure 4.

7, the folded material webs 11, from which the individual Layers of the carrier material 10 are formed, with flow guide means e.g. be provided in the form of triangular wings 18. Each wing 18 is one assigned to the connection openings 14. The flow in a corresponding manner Wing 18 support a redirection of the flow from the one channel through the connection opening 14 into the adjacent channel. In the present In this case, the vanes 18 also serve as turbulators operating in a flow comes into contact with the wings 18, vortex formation and thus turbulence stimulate.

In the embodiment according to FIG. 7, the connection openings 14, Flow guide and the turbulators in the form of the wing 18 particularly simple e.g. be produced by punching processes. In this case, 18 two triangle sides cut free so that the wing 18 around the third triangle side can be bent over such that the wing 18 projects into one of the channels. By bending the wings 18 out of the material web 11 arise there triangular openings, which form the connecting openings 14.

In another embodiment, the layers are through according to FIG. 8 Rectangularly folded material webs 11 formed, which instead of apex lines Have apex surfaces 19. Here, too, are the connection openings 14 and Wing 18, which serve as flow guide and turbulators, preferably produced by a punching process with cutting free and bending the wing 18. In this special embodiment, however, that side of the triangle runs of the wing 18 on which the bending deformation of the wing 18 takes place, for example transversely to the direction of extent of the apex surfaces 19 of the associated material web 11. In addition, a tip 20 of each wing 18 points upstream, that is, opposite the direction of flow. Furthermore, the wings 18 can be as far from the respective Stick out wall that they are on a parallel, opposite wall come to the plant.

FIG. 9 shows an arrangement of seven guide vane structures 21, which are arranged transversely to a flow direction in one of the channels can. Such a guide vane structure 21 forces one flowing through it Flow a rotation around a parallel to the flow direction Axis on. In the present case, the guide vane structures 21 have a hexagonal circumference, which creates a corresponding for the adjacent channels Honeycomb structure results. Each of these vane structures 21 has a plurality of blades 22, which are inclined to the direction of flow, and thus are oriented so that the desired rotation occurs downstream of the guide vane structure 21 in the flow.

In a first exemplary embodiment corresponding to FIG. 1, the catalyst structure 4, for example, consist entirely of a fiber fabric, which with a Catalyst is coated. This structure ensures a low thermal Storage capacity for the catalyst structure 4 and leads to an advantageous Ignition characteristics. In addition, this structure ensures a favorable Temperature transport and flow exchange between the neighboring ones Channels within the catalyst structure. Due to the surface quality of the fabric material, the walls of the channels have a certain roughness, which causes vortex formation in the flow and thus intensive mixing is promoted. By appropriate design of the so formed Catalytic converter structure 4 can sufficiently swirl at outlet end 8 or turbulence can be achieved in the flow, so that the burnout zone 6 relative can be built small.

In a second embodiment corresponding to FIG. 2, the inlet zone 9 _{I is} catalytically inactive or inert and is equipped with turbulators, not shown here. As a result of this measure, the inlet zone 9 _{I works} as a static mixer which ensures homogeneous mixing of the gas flow 3 with the injected fuel. In the middle zone 9 _II , the support material is coated with a catalyst. The individual sub-zones 9 _IIa to 9 _IId can differ from one another in terms of catalytic activity and / or in terms of flow properties (for example turbulator density). In this middle zone 9 _II , the catalyst initiates the combustion reaction of the reaction mixture. Due to the structure of the individual sub-zones 9 _IIa to 9 _IId , this catalytically active region of the catalyst structure 4 is specifically designed in such a way that a low ignition temperature is reached, and in addition the formation of a homogeneous gas phase reaction within the catalyst structure 4 is avoided. In particular, one or the other of the partial zones 9 _IIa to 9 _{IId can also be made} catalytically inactive or inert. In this embodiment, the outlet zone 9 _III is again catalytically inactive or inert and has turbulators in order in this way to achieve intensive mixing of the individual channel flows at the outlet 8 of the catalyst structure 4. This intensive swirling also has the consequence here that the burner 1 manages with a relatively short burnout zone 6.

According to a third embodiment according to FIG. 3, the inlet zone 9 _I is designed in such a way that a relatively strong mixing is formed between the adjacent channels, which causes a correspondingly intensive temperature compensation. This can be achieved in particular by means of appropriately arranged turbulators. Furthermore, the inlet zone 9 _{I is designed to be} catalytically highly active, so that the inlet zone 9 _I serves as an ignition zone. These properties of the inlet zone 9 _{I can} be realized particularly simply by using a metal fiber fabric as the carrier material, which is coated with the highly active catalyst. The middle zone 9 _II is also coated with a catalyst, the middle zone 9 _{II being designed} for a minimal pressure drop, which reduces the risk that a homogeneous gas phase reaction is ignited within the catalyst structure 4. For example, the middle zone 9 _II can be subdivided into several partial zones 9 _IIa to 9 _IIc , which differ from one another, for example, in terms of their catalytic activity. In particular, active and inert sub-zones can follow one another. The outlet zone 9 _III again has turbulators for generating an intensive swirling and mixing at the outlet end 8 of the catalyst structure 4. The outlet zone 9 _III can be designed to be catalytically active or inactive. The middle zone 9 _II and the outlet zone 9 _III can also be made from a porous fiber fabric in this embodiment; alternatively, a thin metal foil or a ceramic carrier material can also be used.

LIST OF REFERENCE NUMBERS

1

burner

2

Fuel injection system

3

gas flow

4

Catalyst structure

5

stabilization zone

6

burnout

7

Inlet end of 4

8th

Outlet end of 4

9

Zone of 4th

9 _I

inlet zone

9 _II

middle zone

9 _III

outlet zone

10

support material

11

web

12

crest line

13

channel

14

connecting opening

15

flow direction

16

web

17

flat wall section

18

wing

19

apex surface

20

triangle top

21

vane structure

22

shovel

Claims (24)

Catalytically operating burner, in particular for a gas turbine installation, with a catalyst structure (4) which has a heat-resistant carrier material (10) which forms the walls of a plurality of adjacent channels (13) which penetrate the catalyst structure (4) in the longitudinal direction and allow a flow through the catalyst structure (4) with a gaseous reaction mixture, at least some of the walls being coated with a catalyst, characterized in that between an inlet end (7) and an outlet end (8) of the catalyst structure (4 ) Connection openings (14) are formed in the walls through which adjacent channels (13) communicate with each other. Burner according to claim 1, characterized in that at least one of the connecting openings (14) is associated with flow guiding means (18) which redirect at least part of the flow of a channel (13) into an adjacent channel (13) communicating therewith through the connecting opening (14) , Burner according to claim 1 or 2, characterized in that at least one of the connection openings (14) is assigned a turbulator (18). Burner at least according to claim 2, characterized in that the flow guide means are designed as a turbulator (18). Burner according to one of claims 1 to 4, characterized in that the channels (13) at least partially form a tortuous flow path through the catalyst structure (4). Burner according to one of Claims 1 to 5, characterized in that the walls are coated with the catalyst in such a way that some of the channels (13) are catalytically active, while other channels (13) are catalytically inactive or inert. Burner according to one of claims 1 to 6, characterized in that the coating of the walls with the catalyst is designed such that at least some of the channels (13) have at least one catalytically active zone and at least one catalytically inactive or inert zone in the flow direction. Burner according to one of Claims 1 to 7, characterized in that the walls are coated with the catalyst in such a way that at least some of the channels (13) have a plurality of active zones in the direction of flow, the catalytic activities of which are different. Burner according to one of claims 1 to 8, characterized in that at least part of the carrier material (10) coated with the catalyst consists of a porous material. Burner according to one of claims 1 to 9, characterized in that at least part of the carrier material (10) coated with the catalyst consists of a fiber fabric. Burner according to one of claims 1 to 10, characterized in that at least a part of the carrier material (10) coated with the catalyst consists of a metal foil. Burner according to one of Claims 1 to 11, characterized in that turbulators (18) are arranged in the channels (13), these turbulators being distributed along the catalyst structure (4) in the channels (13) in such a way that the catalyst Structure (4) in the flow direction has at least one zone equipped with the turbulators and at least one turbulator-free zone. Burner according to claim 12, characterized in that one of the at least one zones equipped with the turbulators (18) has the outlet end (8) of the catalyst structure (4). Burner according to Claim 13, characterized in that the zone (9 _III ) of the catalyst structure (4) which has the outlet end (8) is designed to be catalytically inactive or inert. Burner according to one of Claims 12 to 14, characterized in that one of the at least one zones equipped with the turbulators (18) has the inlet end (7) of the catalyst structure (4), this zone (9 _I ) also being catalytically inactive or is designed to be inert. Burner according to one of Claims 12 to 15, characterized in that a zone (9 _I ) of the catalytic converter structure (4) which has the inlet end (7) is equipped with turbulators (18) and is designed to be catalytically inactive or inert that in one area at least one catalytically active zone (9 _II ) is formed between the inlet end (7) and outlet end (8) of the catalyst structure (4), that a zone (9 _III ) of the catalyst structure (4) having the outlet end (8) Turbulators (18) and catalytically inactive or inert. Burner according to one of Claims 12 to 15, characterized in that a zone (9 _I ) of the catalytic converter structure (4) which has the inlet end (7) is equipped with turbulators (18) and is catalytically highly active in a region between Inlet end (7) and outlet end (8) of the catalyst structure (4) a turbulator-free zone (9 _II ) is catalytically active that a zone (9 _III ) of the catalyst structure (4) with the outlet end (8) with turbulators (18) is equipped. Burner according to one of claims 1 to 17, characterized in that the carrier material (10) consists at least partially of several layers, each layer being formed from a zig-zag or triangular or rectangular-wave folded and / or corrugated material web (11) , the apex lines (12) or apex surfaces (19) of the folds and / or waves being oriented differently in the case of material webs (11) adjacent to the flow direction, adjacent material webs (11) on the intersecting apex lines (12) or apex surfaces (19) abut each other and form the channels (13) between them. Burner according to claim 18, characterized in that the apex lines (12) or apex surfaces (19) are aligned inclined to the longitudinal direction of the catalyst structure (4). Burner according to one of claims 1 to 19, characterized in that the carrier material (10) at least partially consists of a multiply folded material web (16), the apex lines (12) or apex surfaces of the folds approximately in the longitudinal direction of the catalyst structure (4) extend, with flat wall sections (17) being formed between successive apex lines (12) or apex surfaces, with adjacent flat wall sections (17) running parallel to one another and with the channels (13) being formed between the adjacent wall sections (17). Burner according to one of claims 1 to 20, characterized in that the flow directing means and / or the turbulators in the walls are formed by triangular wings (18), two triangular sides of the wing (18) being cut free and the wing (18) the third side of the triangle is bent over so that the wing (18) protrudes into one of the channels (13), the triangular openings formed in the walls forming the connecting openings (14). Burner according to claim 21, characterized in that the bent triangular side of the wing (18) extends approximately transversely to the direction of extension of the apex lines (12) or apex surfaces (19) of the material web (11) and that the triangular tip (20) of the wing (18) upstream shows. Burner according to one of Claims 1 to 22, characterized in that at least one of the channels (13) along the catalyst structure (4) has at least one guide vane structure (21) oriented transversely to the direction of flow, which rotates a flow flowing through it about an axis running parallel to the direction of flow. Use of a catalyst structure with a heat-resistant support material (10), which forms the walls of several adjacent channels (13), which penetrate the catalyst structure (4) in the longitudinal direction and a Flow through the catalyst structure (4) with a gaseous reaction mixture allow, with at least part of the walls with a Catalyst is coated and between an inlet end (7) and an outlet end (8) of the catalyst structure (4) connecting openings (14) are formed in the walls through which adjacent channels (13) communicate with each other in a catalytic burner (1).

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