JP2001324137A - Burner device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a burner in which increase of discharged NOx amount can be restrained, and a stable combustion efficiency can be attained, even when the combustion load is changed. SOLUTION: A main flow path M1 for main combustion is provided around a pilot flow path P1 for auxiliary combustion. A main fuel supply means regulating fuel-supply amount to the flow path M1, and a pilot fuel supply means regulating fuel-supply amount to the flow path P1, and an air-supply means 6 supplying air 2 to the flow path P1 are provided to the burner device. An equivalence ratio between the fuel 1 and the air 2 in the flow path M1 is decreased, and the ratio in the path P1 is increased, following the reduction of a combustion load for a rated combustion load in the burner device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel supply system in which a main flow path for performing main combustion is formed around a pilot flow path for performing auxiliary combustion. Main fuel supply means, pilot fuel supply means for supplying fuel while adjusting the amount of fuel supplied to the pilot flow path, and air supply means for supplying air to the main flow path and the pilot flow path. It relates to a burner device.

[0002]

2. Description of the Related Art Various cogeneration systems have been proposed for performing local power generation and district heating.
A typical example of such a cogeneration system includes, for example, a burner device that burns combustion gas, and a gas turbine that is driven to rotate by using the combustion gas generated by the burner device. There is one that generates electricity by using the power.

[0003] A burner device used for such a gas turbine usually includes a main nozzle and a pilot nozzle. The main nozzle is a portion that literally performs main combustion, and the pilot nozzle is for surely igniting the air-fuel mixture supplied from the main nozzle to form a combustion flame. When the gas turbine is operated at the rated load, that is, at the maximum load at which the gas turbine can be stably operated continuously, the main burner and the pilot burner are continuously operated under certain conditions. At this time, the combustion state of the main burner and the combustion state of the pilot burner are maintained at optimal states. Here, the operating state of the burner device that can operate the gas turbine at the rated load is referred to as the rated combustion load state. Further, the maximum design load of the burner device is referred to as a rated combustion load, and specifically, the maximum load at which the burner device can be stably operated continuously. In this state, normally, the combustion efficiency of the burner device becomes maximum and NOx
The burner device is designed so that the generation amount of the burn is minimized.

On the other hand, when reducing the output of the burner device from the rated combustion load state, first, the amount of fuel supplied to the main burner is reduced. Here, the instantaneous load in each operation state of the burner device is referred to as “combustion load”. Generally, the “combustion load” is one of the important factors indicating the performance of a combustion device, and refers to the amount of heat generated per unit time in a unit space of a combustor that is a main component of the combustion device. In order to greatly change the combustion load, for example, the combustion load is reduced by stopping the combustion of some of the plurality of main burners. Conversely, in order to increase the combustion load, the main burner that has been stopped is ignited.

[0005]

However, in the above-mentioned conventional burner device, when the main burner is ignited or extinguished to change the combustion load, the combustion load changes abruptly. Naturally, the combustion efficiency also fluctuates sharply. Therefore, in a gas turbine system or the like using such a burner device, the operating load does not change smoothly, and an impact load acts on the device portion,
Vibration sometimes occurred.

[0006] Further, the rapid fluctuation of the combustion load is caused by
Not only is the factor of deterioration of the combustion efficiency, but also the variation of the combustion temperature, such as a local increase in the combustion temperature, due to a change in the fuel supply state when the main burner is ignited or extinguished. As a result, the above-described conventional burner device has a problem to be solved, such as an increase in the amount of generated NOx, particularly at a position where high-temperature combustion is performed.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks of the conventional burner device and to reduce the emission N even when the combustion load is varied.
An object of the present invention is to provide a burner device capable of suppressing an increase in the amount of Ox and obtaining stable combustion efficiency.

[0008]

(Structure 1) In a burner device according to the present invention, as described in claim 1, as the combustion load of the burner device decreases with respect to the rated combustion load of the burner device. The feature is that the equivalent ratio between the fuel 1 and the air 2 in the main flow path M1 is reduced and the equivalent ratio in the pilot flow path P1 is increased. (Effect) In the burner device according to the present invention, as the combustion load of the burner device is reduced with respect to the rated combustion load, the equivalent ratio of the air-fuel mixture in the main flow passage is reduced, and the air-fuel mixture in the pilot flow passage is reduced. Since the equivalent ratio is increased, a combustion flame can be reliably formed in the pilot flow path, and the air-fuel mixture in the main flow path can be burned by utilizing the heat generated by the combustion. Therefore, even when the supply amount of fuel to the main passage is reduced, the combustion state in the main passage can be stabilized. That is, the main flame can be stably burned even when the burner device is operated at a low load.

(Structure 2) In the burner device according to the present invention, at the time of the rated combustion load, the equivalent ratio in the main flow path M1 is changed to the equivalent ratio in the pilot flow path P1. Can be set the same or larger. (Operation and Effect) In the burner device according to the present invention, for example, air may be further mixed into the air-fuel mixture flowing out of the main flow path and the pilot flow path. In many cases, the air is mixed with the air-fuel mixture flowing out of the main flow path from the outside in the radial direction of the burner device. This means that the air-fuel mixture from the main flow path is first diluted.

In such a case, when the equivalent ratio in the main passage is set to be equal to or larger than the equivalent ratio in the pilot passage at the time of the rated combustion load, the diluted main passage is set. The equivalence ratio of the air-fuel mixture from the flow path;
It is possible to set the equivalent ratio of the air-fuel mixture flowing out of the pilot flow path to be substantially equal. As a result, a stable combustion state can be obtained when the entire burner device is viewed.

(Structure 3) In the burner device according to the present invention, when the combustion load is 50% to 70% of the rated combustion load, the burner device according to the present invention may be configured such that the main flow path M1 is provided. The equivalent ratio can be set smaller than the equivalent ratio in the pilot flow path P1. (Effects) When the combustion load is set smaller than the rated combustion load, if the equivalence ratio of both the pilot flow path and the main flow path is reduced, the combustion becomes unstable or a misfire occurs. And the like may occur. In order to prevent this, as in the present configuration, when the combustion load is 50 to 70% of the rated combustion load, the equivalent ratio in the main passage is set to be smaller than the equivalent ratio in the pilot passage. By setting the value as small as possible, at least the combustion state of the air-fuel mixture flowing out from the pilot flow path is stably maintained. As a result, it is possible to prevent inconveniences such as the misfire from occurring.

(Structure 4) In the burner device according to the present invention, at the time of the rated combustion load, 0 to 20% of the total fuel 1 to be supplied is supplied to the pilot flow path P1 at the time of the rated combustion load. Supply, and as the combustion load decreases,
The proportion of fuel 1 to be supplied to the pilot flow path P1 among the total fuel 1 to be supplied is increased, and when the combustion load is 50 to 70% of the rated combustion load, It may be configured to supply 20 to 40% of the fuel 1 to the pilot flow path P1. (Effects) When the combustion load is 50% to 70% of the rated combustion load as in the present configuration, two out of all the supplied fuels are used.
As long as 0 to 40% of fuel is supplied to the pilot flow path, the operation and effect of the above configuration 3 can be optimally obtained.

(Structure 5) In the burner device according to the present invention, as described in claim 5, any one of claims 1 to 4 can be used as a burner device for a gas turbine system. it can. (Operation and Effect) When a gas turbine system is constructed using the burner device of the present invention as in the present configuration, the configuration 1
As described above, the combustion state of the burner device can be continuously changed, for example, it is possible to prevent the equivalence ratio in the pilot flow passage from extremely lowering. As a result, especially when the gas turbine system is started, the load can be continuously increased.
At that time, a sudden change in the combustion load in the main flow path can be prevented, and an increase in NOx can be suppressed. Moreover,
Since the combustion load in the main flow path can be continuously increased or decreased, a gas turbine system that can easily perform fine adjustment of the load can be obtained.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Summary) A burner device according to the present invention is provided around a pilot flow path P1 for performing auxiliary combustion.
A main flow path M1 for performing main combustion is formed. The main flow path M1 and the pilot flow path P1
In this embodiment, a combustion gas 1A as a fuel 1 and a combustion air 2 are supplied. The fuel 1 is supplied to the main flow path M1 by main fuel supply means M2, and is supplied to the pilot flow path P1 by pilot fuel supply means P2. The main flow path M
The fuel 1 can be supplied to both the fuel flow path 1 and the pilot flow path P1 while adjusting the supply amount. The main flow path M1 and the pilot flow path P1
Is supplied by air supply means. The supply amount of the air 2 is substantially constant in the present embodiment.

The burner device of the present invention reduces the equivalence ratio between fuel 1 and air 2 in the main flow path M1 when reducing the combustion load from a state in which the burner device is operating at the rated combustion load, At the same time, the equivalent ratio in the pilot flow path P1 is increased. That is, when the combustion load is reduced, the total amount of the fuel 1 supplied to the main flow path M1 and the pilot flow path P1 is reduced. The proportion of the supplied fuel 1 is increased. Thereby, even when the combustion load is reduced, at least the pilot flow path P
In No. 1, the combustion flame can be reliably maintained.

Here, the equivalent ratio in the present invention is:
This is a quantity representing the concentration property of the mixture G in which the fuel 1 and the air 2 are mixed, and is defined as follows. Equivalence ratio = (fuel concentration / air concentration) / (fuel concentration / air concentration) st Each concentration is represented by the number of moles, and (fuel concentration / air concentration) st is fuel 1 and air 2 at the theoretical mixing ratio. And the concentration ratio. The stoichiometric mixture ratio is the concentration ratio between the fuel 1 and the air 2 required for its complete oxidation.

Further, when increasing the combustion load,
Since the supply ratio of the fuel 1 to the main flow path M1 can be gradually increased, the equivalent ratio of the air-fuel mixture G does not fluctuate extremely. As a result, a rapid rise in combustion temperature is suppressed, and N
An increase in the generation amount of Ox can be suppressed.
As the combustion gas 1A, for example, city gas can be used.

(Burner Apparatus) An embodiment of a burner apparatus according to the present invention will be described with reference to the drawings. In the present embodiment, an example in which the burner device is provided in a gas turbine system will be described. FIG. 1 is a sectional view of a burner device according to the present invention. FIG. 2 is a sectional view of a main part of the burner device. FIG. 3 is a sectional view taken along line III-III in FIG.

Although not shown, the gas turbine system is provided with a plurality of burner devices. The plurality of burner devices are distributed in the circumferential direction around the rotation axis of the gas turbine 4. Each burner device, for example,
It is attached to a diffuser member 5 provided coaxially with the rotation shaft. The diffuser member 5 is a member that narrows an air flow path 6a that is an air supply unit 6 to supply the combustion air 2 to each burner device.

More specifically, as shown in FIG. 1, the burner device has an outermost peripheral portion formed of a cylindrical case member 7 and a cylindrical combustion case 8 inside the case member 7. And coaxially. Then, a combustion cylinder 9 is arranged inside the combustion case 8. The air 2 for combustion is supplied from the diffuser member 5 into the combustion case 8. Although not shown, the combustion air 2 is supplied in a state compressed by a compressor or the like.

As shown in FIG. 1, one end of the combustion cylinder 9 is provided with a pilot nozzle P3 and a main nozzle M3. The combustion air 2 is supplied to the pilot nozzle P3 and the main nozzle M3 as described later. As shown in FIG. 1, the fuel 1 for combustion is supplied to the pilot nozzle P3 and the main nozzle M3 from the diffuser member 5 via a pilot fuel supply pipe P4 and a main fuel supply pipe M4.

The pilot fuel supply pipe P4 and the main fuel supply pipe M4 are supplied to the injection nozzle body 10. The injection nozzle body 10 is attached to an annular flange body 11 attached to an end of the combustion cylinder 9. As shown in FIG. 2, the inside of the injection nozzle body 10 is partitioned into a first space 12 and a second space 13. The first space 1
2 is connected to the pilot fuel supply pipe P4, and the second space 13 is connected to the main fuel supply pipe M4.
Is connected. Fuel 1 supplied to the first space 12
Is ejected through the first ejection hole 14 into the pilot flow path P1. The fuel 1 supplied to the second space 13 is jetted through the second jet hole 15 to the main flow path M1.

As shown in FIG. 1, the pilot flow path P
1 is supplied with fuel 1 by pilot fuel supply means P2. The pilot fuel supply means P2 includes, in addition to the pilot fuel supply pipe P4, a pilot fuel control valve P5 for adjusting the supply amount of the fuel 1. Further, the main fuel supply means M2 is connected to the main fuel supply pipe M4.
In addition, the main fuel control valve M for adjusting the supply amount of the fuel 1
5

The pilot fuel control valve P5 and the main fuel control valve M5 are provided with control means 16 for adjusting the opening of each control valve. That is, when adjusting the combustion load of the burner device by increasing or decreasing the total amount of the supplied fuel 1, the control means 16 controls the total amount of the supplied fuel 1 and the amount of the fuel 1 to be supplied to the pilot flow path P 1 and the main flow path M 1. The supply ratio of the fuel 1 is appropriately adjusted. A specific mode relating to the supply of the fuel 1 will be described later.

The injection nozzle body 10 is mounted inside the pilot nozzle P3. The pilot nozzle P3 is constituted by a first cylindrical member 17, and is attached to a second cylindrical member 18 attached to the annular flange body 11 via a member 19 provided in the main flow path. Further, inside the first cylindrical member 17, there are inner projections 20 projecting inward in the radial direction Y at intervals in the circumferential direction X.
Are integrally formed, and the injection nozzle body 10 is attached via the inner projection 20. With this configuration, an annular gap 21a exists between the first cylindrical member 17 and the injection nozzle body 10 over substantially the entire area in the circumferential direction X.
The air 2 flows through the gap 21a, and the air 2 further flows through the pilot flow path P1.

The tip of the injection nozzle body 10 and the first
A plurality of first swirlers 22 are provided between the first swirler 22 and the cylindrical member 17. The first swirler 22 is a plurality of fins arranged at intervals in the circumferential direction X. The air 2 flowing through the gap 21 a between the injection nozzle body 10 and the first cylindrical member 17 is swirled by the first swirler 22.

On the other hand, a second swirler 23 is provided between the first cylindrical member 17 and the second cylindrical member 18 functioning as the main nozzle M3. The second swirler 23 is composed of a plurality of fins arranged at intervals in the circumferential direction X. The air 2 flowing between the first cylindrical member 17 and the second cylindrical member 18 is swirled by the second swirler 23. The fuel 1 is supplied to the air 2 immediately after passing through the second swirler 23 through the second ejection holes 15 and the through holes 25. This lean mixture G flows through the main flow path M1.

As shown in FIG. 1, a part of the air 2 flowing through the air passage 6a flows through a space 26 between the combustion cylinder 9 and the combustion case 8. A plurality of air holes 27 are dispersedly arranged in the combustion cylinder 9 along its own circumferential direction X and the flow direction of the air-fuel mixture G. Thereby, the air 2 flowing through the space 26 is introduced into the combustion cylinder 9 through the air holes 27. The introduced air 2 is
It flows along the inner peripheral surface of the combustion cylinder 9 and exhibits functions such as cooling the combustion cylinder 9 and cooling combustion gas existing inside the combustion cylinder 9.

As shown in FIG. 2, the first cylindrical member 1
7 and the tip of the second cylindrical member 18
The air 2 is set so as to be substantially at the same position in the flow direction. The combustion flame generated by burning the air-fuel mixture G is generated from the inside of the first cylindrical member 17 or from the front end in the pilot flow path P1. On the other hand, the combustion flame in the main flow path M1 is generated from the tip of the second cylindrical member 18. These combustion flames are formed inside the combustion cylinder 9.

The gap 21a between the injection nozzle body 10 and the first cylindrical member 17 is set smaller than the gap 21b between the first cylindrical member 17 and the second cylindrical member 18. Thereby, the amount of the air 2 flowing through the main flow path M1 is larger than the amount of the air 2 flowing through the pilot flow path P1. In the pilot flow path P1, the flow path cross-sectional area on the lower side of the first swirler 22 is configured to rapidly expand, but the flow path cross-sectional area of one main flow path M1 is set to be substantially constant. I have. As a result, the pilot flow path P1
The flow velocity of the air 2 flowing through the main flow path M1 is significantly slower than the flow velocity of the air 2 flowing through the main flow path M1.

As shown in FIG. 1, a tubular lead-out tube 28 is attached to the tip of the combustion tube 9. Outgoing cylinder 2
The distal end of the combustion case 8 is supported by a distal end of the combustion case 8 via a support plate 29. In the vicinity of the outlet of the outlet cylinder 28, the gas turbine 4
Is arranged. That is, the gas turbine 4 is rotationally driven by the combustion gas generated by combustion in the combustion tube 9.

The ignition of the mixture G is performed as shown in FIG.
This is performed using the ignition means 32 extending from the case member 7 to the pilot nozzle P3. The ignition means 32 has an elongated ignition member 32a, and penetrates through the combustion case 8, the combustion cylinder 9, the second cylindrical member 18, and the first cylindrical member 17. As shown in FIGS. 1 to 3, the ignition member 32 a is provided so as to penetrate the inside of the main flow path disposing member 19 provided between the first cylindrical member 17 and the second cylindrical member 18. is there. The four main flow path distributing members 19 are provided inside the main flow path M1 and are dispersed in the circumferential direction X. The main flow passage arranging member 19
Is provided along the radial direction Y of the burner device inside the main flow path M1, but the cross-sectional shape of the main flow path disposing member 19 when cut along a plane perpendicular to the radial direction Y is as follows: In order to suppress an increase in the flow resistance of the air-fuel mixture G, a blade shape is adopted.

In the present burner apparatus, as shown in FIG. 3, the total cross-sectional area of the main flow passage arranging member 19 is 20% of the cross-sectional area of the main flow path M1 on the cut plane III-III in FIG. %. This suppresses an increase in pressure loss of the lean mixture flowing inside the main flow path M1.

[0034] A spark can be generated from the tip ignition portion of the ignition member 32a.
1 ignites the mixture G flowing through. Pilot flow path P1
Is propagated to the air-fuel mixture G flowing through the main flow path M1 to form a flame also in the main flow path M1.

As described above, if the ignition member 32a is disposed so as to penetrate through one of the uniformly disposed members 19 in the main flow path, the ignition member 32a allows the air-fuel mixture flowing in the main flow path M1 to be mixed. It does not affect G. As a result, it is possible to prevent the combustion flame formed in the main nozzle M3 from being disturbed, to suppress the bias of the flame temperature distribution, and to increase the average temperature of the combustion gas by making the combustion state sound. . However, as a result of a healthy combustion state, it is possible to prevent a situation where the combustion temperature rises locally, and it is possible to suppress the generation of NOx.

(Operation Example of Burner Apparatus) The results of a combustion experiment performed using the burner apparatus of the present invention are shown below. In the burner device according to the present invention, when changing the combustion load,
The amounts of the fuel 1 supplied to the pilot flow path P1 and the main flow path M1 are individually adjusted. For example, when reducing the combustion load of the burner device, the equivalence ratio between the fuel 1 and the air 2 supplied to the main flow path M1 is made smaller than the equivalence ratio supplied to the pilot flow path P1. Specifically, while reducing the total amount of fuel 1 supplied to the burner device and reducing the combustion load, the distribution ratio of fuel 1 to the main flow path M1 is changed to the distribution ratio of fuel 1 to the pilot flow path P1. Lower than that.

For example, Table 1 shows an example in which a burner device burning at the rated load is reduced to a combustion load of 62%.

[0038]

[Table 1]

As described above, the equivalent ratio in the main passage M1 at the rated combustion load is set to 0.73, and the equivalent ratio in the pilot passage P1 at the same rated combustion load is set to 0.6.
As 7, the equivalence ratio in the main flow path M1 was set large. As the fuel 1, 10% of the total fuel 1 to be supplied was supplied to the pilot flow path P1. The reason why the equivalent ratio of the main passage M1 is set to be somewhat larger than the equivalent ratio in the pilot passage P1 is that the equivalent ratio inside the combustion cylinder 9 is changed by the air 2 flowing from the air hole 27. This is in consideration of becoming smaller. That is, the air 2 flowing from the air holes 27 first mixes with the air-fuel mixture G flowing out of the main flow path M1,
The equivalent ratio of the mixture G from 1 is reduced. By making the equivalent ratio of the air-fuel mixture G having the reduced equivalence ratio equal to the equivalent ratio of the air-fuel mixture G flowing out of the pilot flow path P1, it is intended to obtain a stable combustion state as a whole. .

Thereafter, the combustion load is reduced to the rated combustion load of 62.
% And combustion was performed. In the present embodiment, the equivalent ratio in the main flow path M1 is set to 0.47, the equivalent ratio in the pilot flow path P1 is set to 1.35, and the equivalent ratio in the main flow path M1 is set smaller. . The fuel 1 increases the ratio of the fuel 1 to be supplied to the pilot flow path P1 to the total fuel 1 to be supplied, and 26
% Of fuel 1 was supplied to the pilot flow path P1.

As described above, when the combustion load is set small, if the pilot flow path P1 and the main flow path M1
If the equivalent ratio of both is reduced, inconveniences such as unstable combustion and misfire may occur. In order to prevent this, the equivalence ratio of the pilot flow path P1 is set to be large in order to stably maintain at least the combustion state of the air-fuel mixture G from the pilot flow path P1.

As a result of this experiment, even if the combustion load was changed,
The change in the combustion state became smooth, and there was no local increase in the combustion temperature. As a result of performing an open-air combustion test, the amount of generated NOx was 13 ppm or less (oxygen 0
% Conversion or less), and it was confirmed that good combustion could be performed. It was also confirmed that a smooth combustion operation with little fluctuation in combustion efficiency could be performed.

(Effects) As described above, in the burner device according to the present invention, as the combustion load of the burner device decreases with respect to the rated combustion load of the burner device, the main flow path M1
Since the equivalent ratio between the fuel 1 and the air 2 in the above is reduced and the equivalent ratio in the pilot flow path P1 is increased, a combustion flame is reliably formed in the pilot flow path, and heat generated by the combustion is reduced. The mixture in the main passage can be burned by utilizing the mixture. Therefore, the amount of fuel supplied to the burner device can be reduced, and the main flame can be stably maintained even when the burner device is operated with a low load.

In particular, when the load is low, the combustion amount of the entire burner device is reduced, so that no high-temperature portion is generated.
The generation amount of NOx can be reduced. Although the fuel supply ratio to the main flow passage is reduced, the fuel supply ratio to the pilot flow passage is increased to increase the flame holding power of the pilot combustion. As a result, the main flame can be sufficiently stably burned. it can.

On the other hand, when the load is high, the fuel supply rate to the main flow path is increased, and the fuel supply rate to the pilot flow path is decreased. In this case, since the main combustion burns a lean air-fuel mixture, local high-temperature combustion hardly occurs, and as a result, the amount of exhausted NOx can be reduced. When the load is high, the fuel supply ratio to the pilot flow path is reduced. In this case, however, since the amount of combustion on the main side increases, no misfire or the like occurs in the main combustion, and the burner device as a whole Stable combustion becomes possible.

[Other Embodiments] <1> The burner device of the present invention can be used as a burner device for various devices such as a burner device for a gas turbine system. If the burner device according to the present invention is used, the load can be continuously increased, particularly when the gas turbine system is started up.
At that time, a sudden change in the combustion load in the main flow path can be prevented, and an increase in NOx can be suppressed. Moreover,
Since the combustion load of the main passage can be continuously increased or decreased, a gas turbine system capable of easily performing fine adjustment of the load can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a burner device according to the present invention.

FIG. 2 is a sectional view showing a main part of the burner device.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

[Explanation of symbols]

 Reference Signs List 1 fuel 2 air 6 air supply means M1 main flow path M2 main fuel supply means P1 pilot flow path P2 pilot fuel supply means

Claims (5)

[Claims] 1. A main fuel supply means for forming a main flow path for performing main combustion around a pilot flow path for performing auxiliary combustion, and supplying fuel while adjusting a fuel supply amount to the main flow path; A burner device comprising: a pilot fuel supply unit that supplies fuel while adjusting a fuel supply amount to the pilot passage; and an air supply unit that supplies air to the main passage and the pilot passage. With respect to the rated combustion load of the burner device, as the combustion load of the burner device decreases, the equivalent ratio between fuel and air in the main passage is reduced, and the equivalent ratio in the pilot passage is reduced. Burner device characterized by increasing. 2. The burner according to claim 1, wherein the equivalent ratio in the main passage is set to be equal to or larger than the equivalent ratio in the pilot passage at the time of the rated combustion load. apparatus. 3. The combustion load is 5 times the rated combustion load.
3. The burner device according to claim 2, wherein when the ratio is 0% to 70%, the equivalent ratio in the main passage is set smaller than the equivalent ratio in the pilot passage. 4. At the time of the rated combustion load, 0 to 20% of the total fuel to be supplied is supplied to the pilot flow path, and the pilot flow of the total fuel to be supplied is reduced as the combustion load decreases. When the combustion load is 50 to 70% of the rated combustion load, 20 to 40% of the total fuel to be supplied is supplied to the pilot passage. The burner device according to claim 3, wherein the burner device is configured to perform the following. 5. A gas turbine system comprising the burner device according to claim 1 as a burner device for a turbine.