JPH1073254A - Low nox combustion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a combustion device, not so long in the total length thereof, simple in construction as well as control and capable of reducing the generation of NOx. SOLUTION: In a combustion device provided with a burner 3, into which compressor outlet air 5 flows through a fuel injection nozzle 4 and fuel 10 is injected, and a liner 2, arranged so as to wrap the outer periphery of the burner 3, the burner 3 is formed of a porous material, containing a catalyst, and the liner 2 is also formed of a porous material, containing a catalyst, while a water/vapor supplying tube or a reducing gas supplying tube is connected to the fuel injection nozzle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low NOx combustion apparatus applied to gas turbine engines for power generation, cogeneration, marine, mechanical drive, and aviation.

[0002]

2. Description of the Related Art In a conventional two-stage combustion type low-pollution combustion apparatus, as shown in FIG.
When the output is low, fuel is injected from the pre-combustion chamber fuel nozzle 15 and the pre-combustion chamber 16 is formed.
When the engine is at a high output, fuel is also injected from the main combustion chamber nozzle 17 and lean combustion is performed in the main combustion chamber 18 to reduce the amount of NOx generated.

In a conventional catalytic low-pollution combustion apparatus, as shown in FIG. 5B, compressed air that has passed through a flow rate adjusting plate 19 is mixed with fuel supplied from a lean premix nozzle 20. After it is burned in the pre-combustion chamber 21, it flows into the main combustion chamber 24. Furthermore, in the main combustion chamber 24 is mixed with fuel injected from the main fuel supply pipe 22 passes through the catalyst 23 after burning, the NOx catalyst 23 has occurred has been turned into a low NOx was reduced to N _2.

[0004]

As a conventional low NOx combustion apparatus, as described above, lean combustion is performed in the main combustion chamber to reduce N2.
Two-stage combustion type to reduce the amount of Ox generated, or N2 after combustion
A catalytic formula that absorbs Ox has been used.

[0005] In the case of these devices, there have been problems in that "the structure and control are complicated" and "the total length of the catalyst incorporating portion is long". The present invention seeks to solve the above problems.

[0006]

[Means for Solving the Problems]

(1) The invention according to claim 1 includes a fuel injection nozzle to which air and fuel are supplied from a compressor outlet, a combustor to which the nozzle is connected, and a liner disposed to surround the outer periphery of the combustor. In the combustion device provided, the combustor is formed of a porous material containing a catalyst.

In the above, the compressor outlet air passes through the fuel injection nozzle and flows into the combustor, and the fuel is injected into the combustor by the fuel injection nozzle, and the two are uniformly mixed in the combustor, and the fuel is mixed. Burns.

[0008] Since the above-mentioned combustor is formed of a porous material containing a catalyst, NO generated during combustion of the above-mentioned fuel is generated.
x is quickly reduced to N ₂ by a catalytic reaction, and NOx can be reduced.

(2) According to a second aspect of the present invention, in the low NOx combustion apparatus according to the first aspect, the liner is formed of a porous material containing a catalyst.

In the above, since the liner is formed of a porous material containing a catalyst, NOx generated immediately after combustion of the fuel is also reduced to N _2, and the NOx is further reduced as compared with the invention (1). It becomes possible.

(3) The low NOx combustion apparatus according to the invention (1) or (2),
A water / steam supply pipe connected to the fuel injection nozzle is provided.

In the above, since water / steam is injected into the combustor together with air and fuel at the compressor outlet, NOx is reduced to N ₂ by the catalyst, and the combustion temperature is reduced. Or NOx compared to (2)
Can be suppressed.

(4) The low NOx combustion apparatus according to the invention (1) or (2),
A reducing gas supply pipe connected to the fuel injection nozzle is provided.

In the above, since the reducing gas is injected into the combustor together with the compressor outlet air and the fuel, a combined effect of the catalytic reaction and the reducing reaction can be obtained. In comparison, the amount of generated NOx can be further suppressed.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A low NOx combustor according to a first embodiment of the present invention will be described with reference to FIGS.

The low N according to the present embodiment shown in FIGS.
The Ox combustion device includes a fuel injection nozzle 4 into which a compressor outlet air 5 discharged from the compressor flows, and a combustor 3 formed of a briquette made of a porous material containing a catalyst and having an ignition plug 9 connected to the nozzle 4. A liner 2, which is provided so as to surround the outer periphery of the combustor 3 and is formed of a porous material containing a catalyst;
And a fuel supply pipe 8 connected to the fuel injection nozzle 4
It has.

In the above, the compressor outlet air 5 passes through the fuel injection nozzle 4 evenly and flows into the combustor 3. The fuel 10 passes through the fuel supply pipe 8 and passes through the fuel injection nozzle 4.
From the combustor 3.

The compressor outlet air 5 and fuel 10 are mixed inside the combustor 3 and then ignited by a spark plug to form combustion gas 6. In the process of passing through the inside of the combustor 3 and the inside of the liner 2, NOx is reduced to N ₂ by a catalyst, and the combustion gas 6 is discharged from the combustion device as a NOx-reduced combustor outlet gas 7. .

The porous material in which the combustor 3 and the liner 2 are formed is made of ceramics, and the mesh of each hole is 1/32 inch or more, and the catalyst contained therein is supported on the surface of ceramic honeycomb or alumina pellets. Noble metal such as platinum. Therefore, the combustor outlet gas 7 can reduce the NOx amount to about 60 to 70 ppm.

Next, according to the second embodiment of the present invention, the low N
The Ox combustion device will be described with reference to FIG. The second embodiment shown in FIG. 3 includes a water / steam supply pipe 11 connected to the fuel injection nozzle 4 in the low NOx combustion apparatus according to the first embodiment.

In the above description, the fuel injection nozzle 4 is
As in the embodiment, the air is passed through the compressor outlet air 5 to inject fuel, and the water / steam 12 supplied from the water / steam supply pipe 11 is evenly injected into the combustor 3. This water /
The steam 12 converts NOx into N by a catalytic reaction in the combustor 3.
₂ and at the same time lower the combustion temperature of the combustion gas 6,
The amount of generated NOx is reduced.

The injection amount of the water / steam 12 is about 0.5 to 1.5 in weight ratio to the fuel 10, and when the weight ratio is 0.5, the NOx amount can be halved.
1.0 can be reduced to 1/3.

Next, according to the third embodiment of the present invention, the low N
The Ox combustion device will be described with reference to FIG. The present embodiment shown in FIG. 4 includes a reducing gas supply pipe 13 connected to the fuel injection nozzle 4 in the low NOx combustion apparatus according to the first embodiment.

In the above description, the fuel injection nozzle 4 is
As in the embodiment, the air is passed through the compressor outlet air 5 to inject fuel, and the reducing gas 14 supplied from the reducing gas supply pipe 13 is evenly injected into the combustor 3.

In the combustor 3 into which the fuel 10 and the reducing gas 14 have been injected, a reaction of the combustion gas 6 with the reducing gas 14 is performed together with a catalytic reaction to reduce NOx to N ₂ ,
Ox generation is reduced.

Although the reducing gas 14 is most preferably NH ₃ , it is also possible to use CO, H ₂ , HC and the like, and it is necessary to supply a reducing gas having a concentration approximately equal to or higher than the NOx concentration. The effect of this is the same as in the case of the second embodiment.

[0027]

The low NOx combustion apparatus according to the present invention includes a combustor in which fuel is injected by the flow of compressor outlet air from a fuel injection nozzle, and a liner disposed so as to surround the outer periphery of the combustor. in the combustion apparatus, by which the combustor has to have been formed by entering the catalyst a porous material, not long overall length of the generated NOx to the catalyst is reduced to N ₂ during the combustion of the fuel, the structure and Low NOx with simple control
In addition, NOx generated immediately after combustion of fuel is also reduced by making the liner also made of a porous material containing a catalyst, so that NOx can be further reduced. It becomes possible to further reduce the combustion temperature by connecting the water / steam supply pipe or the reducing gas supply pipe to the fuel injection nozzle, or obtain a combined effect of the catalytic reaction and the reducing reaction. Therefore, the amount of generated NOx can be further suppressed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an engine using a low NOx combustion device according to a first embodiment of the present invention.

FIG. 2 is a detailed explanatory diagram of the combustion device according to the first embodiment.

FIG. 3 is a detailed explanatory view of a combustion device according to a second embodiment of the present invention.

FIG. 4 is a detailed explanatory view of a combustion device according to a third embodiment of the present invention.

FIG. 5 is an explanatory view of a conventional combustion apparatus, in which (a) is an explanatory view of a two-stage combustion type low-pollution combustion apparatus, and (b) is an explanatory view of a catalytic low-pollution combustion apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas turbine engine 2 Liner 3 Combustor 4 Fuel injection nozzle 5 Compressor outlet air 6 Combustion gas 7 Combustor outlet gas 8 Fuel supply pipe 9 Spark plug 10 Fuel 11 Water / steam supply pipe 12 Water / steam 13 Reduction gas supply pipe 14 Reducing gas

Claims (4)

[Claims] 1. A combustion apparatus comprising: a fuel injection nozzle to which compressor outlet air and fuel are supplied; a combustor to which the nozzle is connected; and a liner disposed so as to surround an outer periphery of the combustor. A low NOx combustion device, wherein the combustor is formed of a porous material containing a catalyst. 2. The low NOx combustion apparatus according to claim 1, wherein said liner is formed of a porous material containing a catalyst. 3. The low NOx according to claim 1 or 2.
A low NOx combustion apparatus, comprising: a combustion apparatus including a water / steam supply pipe connected to the fuel injection nozzle. 4. The low NOx according to claim 1 or claim 2.
A low NOx combustion device, comprising: a combustion device; and a reducing gas supply pipe connected to the fuel injection nozzle.