DE10022763A1 - Catalytically converting nitrogen oxide in exhaust gas stream mixed with ammonia to form water and nitrogen comprises feeding gas stream together with added catalytically active substance to reaction chamber - Google Patents

Abstract

Catalytically converting a nitrogen oxide in an exhaust gas stream mixed with ammonia to form water and nitrogen comprises feeding the gas stream (A) together with an added catalytically active substance (S) to a reaction chamber (2). Independent claims are also included for the following: (a) a process for reacting a catalyst module (3) produced by depositing a catalytically active material in or on a catalyst substrate (31) comprising wetting the catalyst module with a catalytically active substance; (b) a fuel for burning in a combustion process containing the catalytically active substance; and (c) an exhaust gas purification device for a power station or a vehicle combustion engine comprising an injection device for injecting the catalytically active substance into the fuel.

Description

The invention is in the field of catalysts.

The invention relates to a method for converting a Substance in a gas stream, especially for catalytic order Conversion of nitrogen oxide into one mixed with ammonia Flue gas flow to water and nitrogen according to the principle of selective catalytic reduction, the gas flow being a Reaction chamber fed and being the substance of the action exposed to a catalytically active material.

The invention also relates to a process for reacti vation of an at least partially deactivated catalyst module that by separating a catalytically active Ma terials produced in or on a catalyst substrate has been, in particular to reactivate one after the Principle of selective catalytic reduction working Catalyst module for the decomposition of nitrogen oxide in a flue gas.

The invention also relates to a fuel for burning in a combustion process.

Furthermore, the invention relates to an exhaust gas cleaner tion system of the first type, in particular for a combustion plant of a power plant or for an internal combustion engine nes motor vehicle in which one arises during combustion existing exhaust gas stream for converting a contained therein Pollutant is guided through a catalyst module that Separate the catalytic conversion of the pollutant promoting catalytically active material on or in one Catalyst substrate is made, in particular in Exhaust gas stream containing nitrogen oxide according to the principle of selek tive catalytic reduction is convertible.  

The invention also relates to an emission control device location of the second type, especially for an incinerator of a power plant or an internal combustion engine of a power vehicle in which one from the combustion of a fuel resulting exhaust gas flow to convert one contained therein NEN pollutant is passed through a catalyst module that by depositing a catalytic conversion of the damage promoting catalytic material on or in a catalyst substrate is produced, in particular nitrogen oxide contained in the exhaust gas flow according to the principle of se selective catalytic reduction is convertible.

The oxidic combustion of fossil fuels creates substances or pollutants in the exhaust gas or flue gas that pollute the environment. For example, in the smoke gases that arise in waste incineration plants, power plants, melting furnaces or heating plants, nitrogen oxides, e.g. B. NO or NO ₂ included. An exhaust gas or fluid stream of comparable type also arises in the combustion of diesel fuel or other fuels in the internal combustion engines of motor vehicles.

To convert the unwanted nitrogen oxides is one under the The term "selective catalytic reduction (SCR)" known method z. B. in a prospectus of Siemens AG with the Order number A96001-U11-A294-V1 from 1996, or from the German patent DE 24 58 888 known.

The nitrogen oxides in this process are added by Ammonia catalytically in harmless nitrogen and water vapor converted. For this purpose, the flue gas or exhaust gas at a Temperature between 300 and 500 ° C by a catalyst or passed through a catalyst module. The catalyst mo dul consists of a ceramic matrix or a kerami cal catalyst substrate on which a catalytically active Material is deposited which is converting the stick causes or promotes oxides in nitrogen and water vapor. On  such catalytic material are, for example, the oxides titanium, vanadium and / or tungsten and / or Mo lybdenum.

It is known that SCR catalysts depending on the Deactivate smoke gas constituents during their operation. The reasons for the deactivation are e.g. B. be chemically establishes, d. H. that the catalytically active material Verbin received that cannot participate in the SCR process. It can also be that the catalyzed in the course of operation effective material from the exhaust gas flow the catalyst module is transported out. This occurs especially if the catalytically active mate rial with halogens contained in the exhaust gas tall-halogen connections.

The deactivation of the SCR catalysts has so far been there compensated by that additional catalyst volume or additional catalyst modules were added. This procedure wise is expensive and time-consuming. When performing the SCR in Technically, it is technically only under irresponsible Rem effort feasible. When used in power plants a power plant shutdown is required.

There is therefore a need to deactivate the ka be analytically effective material through other measures encounter. The invention is therefore based on the object Method, device and substance for this purpose specify.

This task is based on the first Ver drive solved according to the invention in that with the gas A substance is supplied to the reaction chamber, which is catalytically active material or from the catalytic effective material can be formed.  

The substance is preferably added continuously. It discontinuous addition is also possible.

When performing this process is a catalyst module not necessarily required. The catalytic conversion The pollutant in the exhaust gas can only be cata- lytic effective material take place that the reaction space is supplied in the form of the substance. This catalytic active material can be continuous or discontinuous be fed.

According to a preferred embodiment, the gas flow is through a, in particular arranged in the reaction chamber, catalyst or passed past such a substrate.

The substance is preferably the gas stream in flow direction tion added before the catalyst substrate.

In particular, the substance becomes ho when added to the gas stream mogen dispersed or atomized.

The substance is preferably or becomes a fuel beige mixes, the combustion of which is contained in the gas stream Substance is created as exhaust gas.

It is particularly advantageous in or on the catalyst sub was a step promoting the catalytic conversion of the substance catalytically active material forming a catalyst module stored or deposited. So the catalyst module was for example by separating the catalytically active mate rials in a separate manufacturing process before implementation tion of the method according to the invention produced.

If such a catalyst module is completely or partially deactivated tiviert, it is possible with this method, it is virtually in to regenerate in situ. The catalyst module must therefore rain generation are not necessarily taken out of service,  d. H. in particular, a power plant does not have to be go out of service. With a fresh or fresh one Catalyst module becomes one when using this method Deactivation counteracted right from the start.

According to a preferred embodiment, this is catalytic effective material that is supplied with or from the gas stream the substance is formed, the same as that catalytically effective material used in the manufacture of the catalyst module was stored or deposited. This is the catalytic converter door module regenerated in a particularly efficient manner.

In addition, the added or ge in the gas stream acts formed catalytic material itself catalytically, so that even if the catalyst is not regenerated door module would be an increase in catalysis efficiency.

In order to increase the regeneration effect, the before the Ka catalyst module added catalytically active material or the catalytically active material formed from the substance the property of being deposited on the catalyst module.

Another particular advantage is through storage or storage tion of the catalytically active material of the gas stream in or a catalyst module is formed on the catalyst substrate det.

This method is particularly advantageous ter possible, an inert or catalyzed in the gas stream table inactive catalyst substrate to bring. The Kataly sator module then gradually forms through deposition or storage of the formed from or in the substance contained catalytically active material.

The catalyst module is produced in particular in the following steps:

• a) The gas stream is mixed with a substance that catalyzes effective material is or contains or from the ka analytically effective material is separable.
• b) The gas flow is then through or over a kata guided lysator substrate.
• c) By depositing or storing the catalytically active mate rials on or in the catalyst substrate, the Ka Talysatormodul formed.

The procedural task is related to the beginning solved the second-mentioned method according to the invention, that the catalyst module is wetted with a substance that is or contains catalytically active material or from which catalytically active material is separable.

So it is, for example, in or on the catalyst sub strat the catalyst module after the catalyst module for was in operation for a long time, again catalytically effective Ma material on or introduced.

In particular, the catalytically active material of the sub punch in or on the production-related kataly effective material stored and / or deposited.

The catalytically active material is particularly advantageous the substance is the same as the catalytically active mate rial, which is used in the manufacture of the catalyst module or was deposited.

According to a particularly preferred embodiment, the sub punch the catalyst module during catalyst operation fed. Such an online operation has the special Advantage that the catalyst module for regeneration is not au It must be put into operation and therefore no breaks The catalytically influenced process must take place.  

The substance is preferably mixed with a substance which the catalyst module to promote the conversion of the substance is fed. It is therefore advantageously not a ge special material flow to the catalyst module is necessary because the substance is mixed with the substance that is operational is supplied to the catalyst module anyway.

The substance is present for wetting the catalyst module preferably in the vaporized or gaseous state.

According to a preferred variant, the substance is or will be added to a fuel when it burns Substance is created as exhaust gas, which is the catalyst module to the Förde tion of the conversion of the substance is fed.

In all of the processes mentioned, this contains a catalytic effect same material preferably atoms of one of the elements vanadium, Titanium, tungsten, iron and / or molybdenum, and that catalytically active material is in particular an oxide of one of these Me tall. Mixtures of the elements mentioned are also possible.

The object related to a substance is according to the invention thereby by a fuel for combustion in a ver burning process that contains a substance or that contains a sub punch is added, which is catalytically active material or from the catalytically active mate during combustion rial arises. The fuel contains kata in particular or it is catalytically active material Material added.

Such a fuel is particularly useful for carrying out the Suitable method according to the invention, especially for those configurations where explicitly a fuel is used. The above mentioned in this context Parts apply analogously to the fuel.  

The substance content in the fuel preferably has one Value between 10 mg / kg fuel and 200 mg / kg fuel on.

In particular, the fuel content of catalyti material between 50 mg / kg fuel and 100 mg / kg fuel.

The substance, and in particular the catalytically active mate rial, is preferably in dissolved or dispersed form in Contain or contain fuel in soluble or dispersed form gier form added.

The catalytically active material is preferably ge is suitable for the conversion occurring during combustion Promote pollutant.

According to a particularly preferred embodiment, the kata lytically effective material the property, nitrogen oxide after the Convert the principle of selective catalytic reduction, that is contained in the exhaust gas generated during combustion.

According to another preferred embodiment of the fuel contains the catalytically active material at least one of the elements vanadium, titanium, tungsten, iron, molybdenum or Mixtures of these.

The device related task is related to the one initially mentioned exhaust gas cleaning system according to the Invention solved by an injection device with the a substance in the flow direction in front of the catalyst module can be fed into the exhaust gas, the substance being catalytic effective material is or contains or from the substance ka analytically effective material is separable.

The injection device preferably has a storage container container for taking up the substance.  

The device related task is related to the one previously mentioned exhaust gas purification system of the second type according to the Invention solved by a feed device by means of a substance can be added to the fuel, the sub is or contains punch catalytically active material or separable from the substance catalytically active material is.

The exhaust gas cleaning systems of both types are especially for Implementation of the first-mentioned method according to the invention suitable. The advantages mentioned in connection with this apply for these emission control systems analog.

The feed device preferably has a storage container ter to absorb the substance.

Six embodiments of a device according to the inven tion or for explaining a method according to the invention are hereinafter tert with reference to FIGS . 1 to 6. Show it:

Fig. 1 shows a first embodiment of a flue gas washer system according to the invention,

Fig. 2 shows a second embodiment relating to the implementation of a method according to the invention,

Fig. 3 shows a third embodiment relating to a drive Ver according to the invention,

Fig. 4 shows a fourth embodiment relating to a drive Ver according to the invention,

Fig. 5 shows a fifth embodiment relating to a drive Ver according to the invention,

Fig. 6 shows a sixth embodiment relating to an apparatus and a method according to the invention,

Fig. 7 shows a first measurement result, the second embodiment has been achieved with the method according to, and

Fig. 8 shows a second measurement result, which was achieved with the method of the second embodiment.

Fig. 1 shows a line 1 , in which a reaction chamber 2 is ge forms. In the reaction chamber 2 , a catalyst device comprising three catalyst modules 3 is arranged. The Kata lysatormodule 3 are flowed through in the flow direction 5 by a fluid or gas A, which is an exhaust gas or flue gas. The exhaust gas A contains a substance or pollutant, namely nitrogen oxide NO (NO _x ). For the reduction of nitrogen oxides according to the principle of selective catalytic reduction (SCR) of the gas A with the pollutant NO is supplied (NH ₃₎ by means of a reducing agent flow into the line 1 to the first feeding line 7 of ammonia NH. The nitrogen oxides NO, together with the added ammonia NH, enter the catalyst modules 3 in the reaction space 2 . There, the nitrogen oxide NO is converted into nitrogen (N ₂ ) and water vapor (H ₂ O), so that the gas stream emerging after the catalyst modules 3 has a greatly reduced nitrogen oxide content.

The exhaust gas A originates, for example, from the combustion system of a power plant operated with gas, oil or coal. The Kata lysatormodule 3 contain as a catalytically active material K Vanadium, molybdenum, tungsten and / or titanium, in particular in oxidic form. In the preferred temperature range of 300 ° C to 450 ° C, the catalytically active materials K used for the SCR process work highly selectively, so that undesirable side reactions are largely prevented.

The catalyst modules 3 can partially or completely deactivate after prolonged operation. Possible causes of deactivation are the action of dust or the action of chemical compounds, for example halogens contained in the exhaust gas A, on the catalytically active material K.

For the in-situ regeneration of the deactivated catalyst modules 3 , the exhaust gas A is fed in the flow direction 5 upstream of the catalyst modules 3 by means of an injection device 8 new or fresh catalytically active material KU. Instead of catalytically active material KU, the injection device 8 can also be used to supply a substance 5 from which the catalytically active material KU is formed, for example only in the exhaust gas stream A. The added or forming catalytically active material KU is the same or has a similar composition to the catalytically active material K, which is already present in the catalyst modules 3 or was originally present.

The injection device 8 has a storage container 11 for holding the substance S or the catalytically active material KU. Starting from the reservoir 11 , a second feed line 9 opens into the exhaust gas A leading line 1 . The second feed line 9 is designed at its mouth in such a way that the substance S or the catalytically active material KU is dispersed or atomized when entering line 1 .

The line 1 , the catalyst modules 3 and the first feed line 7 together with the injection device 8 form an exhaust gas purification system 13 , which can be used both stationary for an internal combustion system of a power plant and also mobile for an internal combustion engine of a motor vehicle.

The second embodiment of a method according to the invention shown in FIG. 2 differs from that of the first embodiment essentially in that the substance S or the fresh catalytically active material KU is mixed with a fuel B, from which combustion in a combustion chamber 15 the exhaust gas A only arises. In the exemplary embodiment shown, the fuel B, to which the substance S or the catalytically active material KU is added in dissolved or dispersed form, is conveyed into the combustion chamber 15 by means of a fuel line 17 . A pump 19 is provided to deliver the fuel B from a tank 21 . The fuel B contains the substance S or the catalytically active material KU with a proportion between 10 mg / kg fuel and 200 mg / kg fuel.

The fuel B is burned in the combustion chamber 15 , producing nitrogen oxide-containing exhaust gas A. For example, the new catalytically active material KU also forms from the substance S in the combustion chamber 15 . From the combustion chamber 15 , the exhaust gas A with the nitrogen oxide NO and the new catalytically active material KU passes through the line 1 to the catalyst modules 3 in the reaction space 2 . In direction of flow 5 in front of the catalyst modules 3 , ammonia NH is admixed as in the first exemplary embodiment from the first feed line 7 .

By burning the fuel S mixed with substance S or catalytically active material KU for a longer period of time, the catalyst modules 3 are regenerated.

This regeneration can be seen from the measurement result shown in FIG. 7. In the underlying experiment, the fuel B of a refinery power plant was catalytically active material KU added as a mixture of vanadium V and iron Fe. 102 mg vanadium and 252 mg iron per kg fuel B were added. When combusting fuel B, an exhaust gas stream with a volume flow i. N. moist generated from 150,000 m ³ / h. The vanadium content in exhaust gas A or flue gas was 316 ppm. A damp smoke density of 1.31 kg / m ^{3 was used as a} basis. The operating temperature of the catalyst modules 3 was 370 ° C.

The table below shows the vanadium content V2O5 (content of vanadium oxide V2O5) at the start of the combustion of fuel B (t = 0 h) and after approx. 6000 h, measured in each case on the upstream and downstream sides of the Catalyst modules 3 :

In the diagram in FIG. 7, the vanadium content V2O5 in the catalyst modules 3 is plotted in percent on the left ordinate. The time t in hours (h) is plotted on the abscissa.

The vanadium content V2O5 in the partially deactivated catalyst modules 3 was approximately 0.4% at the start of the regeneration measure (t = 0 h). After 6000 operating hours, the vanadium content V2O5 was measured with XRF (= X-ray fluorescence analysis), with a dust covering having been removed beforehand.

The diagram shows that the vanadium content V2O5 had risen to about 1.3%. As a result, the nitrogen oxide-specific catalytic activity K-NOx of the catalyst modules 3 rose from initially approximately 41.5 m / h to approximately 48.5 m / h after 6000 operating hours (right ordinate).

In FIG. 8, the oxidation rate K SOx for the oxidation reaction of SO ₂ to SO ₃ is plotted on the right ordinate. During the 6000-hour observation phase, this increased from initially 200 m / h to approx. 550 m / h.

The third exemplary embodiment shown in FIG. 3 differs from the second exemplary embodiment shown in FIG. 2 first in that the substance S or the fresh catalytically active material KU is not already mixed with the fuel B in the tank 21 , but from a separate one Container 25 to which fuel B is only mixed after it has been conveyed out of tank 21 . In the example shown, the substance S or the catalytically active material KU is fed from the container 25 by means of a feed line 27 to the fuel line 17 , so that the fuel B mixed with the substance S or the fresh catalytically active material KU - as in the exemplary embodiment from Fig. 2 - gets into the combustion chamber 15 . This variant of supplying fuel to the combustion chamber 15 can also be implemented in the exemplary embodiment in FIG. 2. The container 25 and the feed line 27 form a feed device 28 .

The embodiment of FIG. 3 also differs from the embodiment of FIG. 2 in that there are no catalyst modules 3 . In this exemplary embodiment, the catalytic conversion of the nitrogen oxides NO formed in the combustion in the exhaust gas stream A takes place solely by the action of the catalytically active material KU added to the fuel B on the nitrogen oxides NO, in particular in the reaction space 2 .

The fourth exemplary embodiment of a method according to the invention shown in FIG. 4 serves to reactivate an at least partially deactivated catalyst module 3 . In the example shown, the reactivation takes place ex-situ, ie in a state in which the catalyst modules 3 are not used for the catalytic conversion of the substance NO. The deactivated catalyst modules 3 are arranged in the reaction chamber 2 and are wetted with a substance 5 which is or contains new or fresh catalytically active material KU or from which such catalytically active material can be separated. The fresh catalytically active material KU is deposited in or on a catalyst substrate 31 , in or on which 3 catalytic material K was already deposited or deposited during the manufacture of the catalyst modules. The catalyst modules 3 are regenerated in this way.

In the fifth embodiment shown in FIG. 5, an initially inert catalyst substrate 33 is used. This catalyst substrate 33 is acted upon by a gas stream or exhaust gas stream A which arises, for example, when a fuel is burned. The gas stream A is either in a manner analogous to FIGS. 2 or 3 (not explicitly shown in FIG. 5) or by means of a branch line 29 opening into the line 1, a substance S is added which is or contains catalytic material K or from the catalytically active material K can be formed. According to the exemplary embodiment shown in FIG. 5, a catalyst module 3 is thus produced by introducing the inert catalyst substrate 33 into the line 1 through which exhaust gas A flows.

The exhaust gas purification system 41 shown in FIG. 6 as the sixth exemplary embodiment comprises, like the third exemplary embodiment illustrated in FIG. 3, a feed device 28 . In contrast to FIG. 3, however, in the exemplary embodiment shown in FIG. 6, as also in the exemplary embodiment of FIG. 2, catalyst modules 3 are present in the reaction space 2 , which in or by depositing a catalytically active material K in or on a catalyst substrate 31 have been produced. In the exemplary embodiment shown in FIG. 6, the catalyst modules 3 are regenerated by means of the new or fresh catalytically active material added by the feed device 28 or as a KU, or by means of the substance S “in situ” or “online”.

The capacitor modules 3 tet nachgeschal in the direction of flow 5 is a separator 49, in which the Regenerie tion of the catalyst modules 3 unneeded catalytically active material KU, ie such, which is still contained in the exhaust gas stream A to the catalyst modules 3, is separated. A return line 51 leads from the separating device 49 - optionally via a concentrating device (not shown) - to the feed device 28 . In this way, fed but not required catalytically active material KU can be used again for feeding into the fuel B. As a result, the costs for catalytically effective material KU are considerably reduced.

Claims (25)

1. A method for converting a substance (NO) in a gas stream (A), in particular for the catalytic conversion of nitrogen oxide in a flue gas stream mixed with ammonia (NH) to water and nitrogen according to the principle of selective catalytic reduction, the gas stream (A) fed to a reaction chamber ( 2 ) and the substance (NO) being exposed to a catalytically active material (K, KU), characterized in that with the gas stream (A) the reaction chamber ( 2 ) has a substance ( S) is supplied, the catalytically active material (K; KU) or from the catalytically active material (K; KU) can be formed ( FIGS. 1, 2, 3, 5, 6). 2. The method according to claim 1, characterized in that the gas stream (A) through a, in particular in the reaction chamber ( 2 ) arranged, catalyst substrate ( 31 ; 33 ) or is guided past such. 3. The method according to claim 2, characterized in that the substance ( 5 ) to the gas stream (A) in the flow direction ( 5 ) before the catalyst substrate ( 31 ; 33 ) is added ( Fig. 1, 5). 4. The method according to claim 3, characterized in that the sub punch (S) dispersed homogeneously when added to the gas stream (A) or is atomized. 5. The method according to any one of claims 1 to 4, characterized in that the substance (S) is or is mixed with a fuel (B), the combustion of which in the gas stream (A) contains substance (NO) as exhaust gas ( Fig . 2, 3, 6). 6. The method according to any one of claims 2 to 5, characterized in that in or on the catalyst substrate ( 31 ) a catalytic conversion of the substance (NO) promoting catalytically active mate rial (K) forming a catalyst module ( 3 ) or is deposited ( Fig. 1, 2). 7. The method according to claim 6, characterized in that the catalytically active material (KU) which is led to the gas stream (A) or formed from the substance (S) is the same as the catalytically active material (K ), which was stored or deposited in the manufacture of the catalyst module ( 3 ). 8. The method according to any one of claims 2 to 5, characterized in that by inserting or depositing the catalytically active material (K) of the gas stream (A) in or on the catalyst substrate ( 33 ), a catalyst module ( 3 ) is formed ( Fig . 5). 9. A method for reactivating an at least partially activated catalyst module ( 3 ) which has been produced by depositing a catalytically active material (K) in or on a catalyst substrate ( 31 ), in particular for reactivating a catalyst based on the principle of selective catalytic reduction Working catalyst module ( 3 ) for breaking down nitrogen oxide (NO) in a flue gas (A), characterized in that the catalyst module ( 3 ) is wetted with a substance (S) which is or contains or contains catalytically active material (KU) the catalytically active material (KU) is separable ( Fig. 1, 2, 4). 10. The method according to claim 9, characterized in that the kata lyically active material (KU) of the substance (S) in or on  the production-related catalytically active mate rial (K) is stored and / or deposited. 11. The method according to claim 9 or 10, characterized in that the catalytically active material (KU) of the substance (S) is the same as the catalytically active material (K) which in or in the manufacture of the catalyst module ( 3 ) was deposited. 12. The method according to any one of claims 9 to 11, characterized in that the substance (S) is supplied to the catalyst module ( 3 ) during the catalyst operation. 13. The method according to claim 12, characterized in that the substance (S) is mixed with a substance (NO), which is supplied to the catalyst module ( 3 ) to promote the conversion of the substance (NO). 14. The method according to claim 12 or 13, characterized in that the substance (S) is or is mixed with a fuel (B), in the combustion of which a substance (NO) is produced as exhaust gas, which the catalyst module ( 3 ) to promote Conversion of the substance (NO) is supplied. 15. The method according to any one of claims 1 to 14, characterized in that the kata lytically effective material (K, KU) atoms one of the elements Contains vanadium, titanium, tungsten, iron and / or molybdenum, and that the catalytically active material (K, KU) in particular an oxide of one of these metals. 16. Fuel (B) for combustion in a combustion pro zeß, which contains a substance (S) or which a substance (S)  is added, which is catalytically active material (KU) or from the catalytically active mate during combustion rial (KU) arises, especially to carry out the procedure rens according to claim 5 or 14. 17. Fuel (B) according to claim 16, characterized in that its sub Punch content a value between 10 mg / kg fuel and 200 mg / kg Has fuel. 18. Fuel (B) according to claim 16 or 17, characterized in that the sub punch (S) contained in dissolved or dispersed form or is added in soluble or dispersing form. 19. Fuel (B) according to one of claims 16 to 18, characterized in that the kata lyically effective material (KU) has the property that Um conversion of a pollutant resulting from combustion To promote (NO). 20. Fuel (B) according to one of claims 16 to 19, characterized in that the kata lyically active material (KU) has the property of nitric oxide according to the principle of selective catalytic reduction to convert the ent in the exhaust gas generated during combustion hold is. 21. Fuel (B) according to one of claims 16 to 20, characterized in that the kata lyically active material (KU) at least one of the elements Vanadium, titanium, tungsten, iron, molybdenum or mixtures contains from it. 22. exhaust gas cleaning system ( 13 ), in particular for a combustion plant of a power plant or for an internal combustion engine of a motor vehicle, in which an exhaust gas stream (A) arising during combustion for converting a pollutant (NO) contained therein by a catalyst module ( 3 ) ge leads, which is produced by depositing a catalytic conversion of the pollutant (NO) promoting catalytically active material (K) on or in a catalyst substrate ( 31 ), in particular in the exhaust gas stream (A) containing nitrogen oxide according to the principle of selective Catalytic reduction can be converted, characterized by an injection device ( 8 ) with which a substance (S) can be fed into the exhaust gas in the direction of flow ( 5 ) upstream of the catalyst module ( 3 ), the substance (S) being catalytically active material (KU) is or contains or from the substance (S) catalytically active material (KU) can be deposited ( Fig. 1). 23. Exhaust gas purification system ( 13 ) according to claim 22, characterized in that the injection device ( 8 ) has a storage container ( 11 ) for receiving the substance (S). 24. Exhaust gas purification system ( 41 ), in particular for a combustion system of a power plant or an internal combustion engine of a motor vehicle, in which an exhaust gas stream (A) resulting from the combustion of a fuel (B) for converting a pollutant (NO) contained therein by a catalyst module ( 3 ) is performed, which is produced by depositing a catalytic conversion of the pollutant (NO) promoting catalytically active material (K) on or in a catalyst substrate ( 31 ), in particular in the exhaust gas stream (A) contained nitrogen oxide after The principle of selective catalytic reduction is convertible, characterized by a feed device ( 43 ) by means of which the fuel (B) can be added with a substance (S), the substance (S) being or containing or containing catalytically active material (KU) from the substance (S) catalytically active material (KU) can be deposited ( Fig. 6). 25. Exhaust gas purification system ( 41 ) according to claim 24, characterized in that the one feed device ( 28 ) has a storage container ( 45 ) for receiving the substance (S).