JP2002038970A - Gas turbine combustor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas turbine combustor capable of improving the mixing degree of fuel and steam by simplifying a structure without using any special device, and capable of achieving low NOx and low smoke. SOLUTION: This gas turbine combustor is provided with a liquid fuel supplying part 20a for atomizing and supplying liquid fuel, an air supplying part 51a for supplying combustion air, and a steam supplying part 40a for supplying steam, and the atomized liquid fuel, the combustion air and the steam are mixed to each other and burnt. A steam passage 40 of the steam supplying part is provided around a liquid fuel nozzle 21 of the liquid fuel supplying part, a combustion air passage 51s of the air supplying part is provided on the outer peripheral part of it, a wall body 5a having mixed gas flow holes 32 is provided on the front surface part in the injecting direction of the liquid fuel nozzle, the atomized liquid fuel and the steam are allowed to flow to the mixed gas flow holes 32, and the mixed gas is injected to the air flow passage 51s.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine combustor, and more particularly to a gas turbine combustor using liquid fuel as fuel.

[0002]

2. Description of the Related Art Conventionally, gaseous fuel has been mainly used as fuel for gas turbine combustors, but liquid fuel has recently been used. In gas turbine combustors using liquid fuel as fuel,
A major technical issue is how to suppress the rise in flame temperature in the combustion chamber in order to suppress the emission of nitrogen oxides (NOx) and soot (smoke), which are air pollutants.

In general, a liquid fuel is sprayed / atomized using an air flow having a pressure higher than the internal pressure of a combustor to suppress the generation of a local high-temperature field in a combustion chamber, Normally, steam is previously mixed into the combustion air introduced into the nozzle to lower the flame temperature of the entire combustion chamber, thereby reducing the emission of NOx and smoke.

[0004] In connection with the atomization of the liquid fuel, for example, as disclosed in Japanese Patent Application Laid-Open No. H11-211086, the air flow of the fuel spray air in which the liquid fuel is bled / pressurized from a compressor. A liquid fuel injected from the center of a fuel nozzle is atomized by using a high-pressure swirling flow on the outer periphery of the nozzle as disclosed in Japanese Patent Application Laid-Open No. 8-145363. For example, Japanese Unexamined Patent Publication No. 55-82230 discloses a method in which a heated steam flow is added around liquid fuel sprayed into a combustion chamber. There is one that promotes the evaporation of the fuel droplets.

[0005]

The combustion system in which a heated steam flow is added around the sprayed liquid fuel has a uniform and uniform mixture of the sprayed fuel and the steam to be added. In this case, it is very effective and a nearly satisfactory combustion state can be obtained, but on the other hand, if the mixing state of this fuel and steam is poor, an expensive combustor configuration with steam supply equipment is used. Nevertheless, there is a dislike that the flame temperature does not drop and does not contribute to the effect of reducing NOx and smoke emissions at all.

[0006] For these reasons, it has recently become a major issue how to atomize liquid fuel and increase the degree of uniform mixing of atomized spray fuel and steam. The present invention has been made in view of the above, and an object of the present invention is to simplify the configuration without using a special device and to increase the degree of atomization of liquid fuel and the uniform mixing degree of fuel and steam. Another object of the present invention is to provide a gas turbine combustor of this type that can achieve low NOx and low smoke.

[0007]

That is, the present invention comprises a liquid fuel supply unit for supplying liquid fuel in a spray form, an air supply unit for supplying combustion air, and a vapor supply unit for supplying steam. In the gas turbine combustor in which the spray liquid fuel, the combustion air and the steam are mixed and burned, a mixed gas of the spray liquid fuel and the steam flows to the front surface of the spray of the spray liquid fuel. A wall having a mixed gas flow hole is provided, and a discharge side end of the mixed gas flow hole is formed so as to open to the combustion air flow passage, thereby achieving an intended purpose. .

The present invention further comprises a liquid fuel supply unit for supplying the liquid fuel in the form of spray, an air supply unit for supplying combustion air, and a vapor supply unit for supplying steam. In a gas turbine combustor configured to mix and burn combustion air and the steam, a steam flow path of the steam supply unit is provided around a liquid fuel nozzle of the liquid fuel supply unit, and an outer peripheral portion thereof is provided. A combustion air flow path of the air supply unit is provided, and a wall having a mixed gas flow hole is provided at a front surface of the liquid fuel nozzle in a jet direction, and the sprayed liquid fuel and the vapor flow through the mixed gas flow hole. And the two mixed gases are injected into the air flow passage.

That is, in the gas turbine combustor formed as described above, the vapor flow path of the vapor supply section is provided around the liquid fuel nozzle of the liquid fuel supply section, and the air supply section of the air supply section is provided on the outer periphery thereof. A combustion air flow path is provided, a wall having a mixed gas flow hole is provided on the front side of the liquid fuel nozzle in the injection direction, and the sprayed liquid fuel and vapor flow through the mixed gas flow hole, and Since the two mixed gases are formed so as to be injected into the air flow passage, the liquid fuel from the fuel nozzle is injected toward the mixed gas flow passage (spray fuel injection hole) of the wall, and the sprayed fuel is injected. A fuel liquid film is formed on the inner wall of the hole, and steam flows into the sprayed fuel ejection hole, the momentum of the steam flow is transmitted to the fuel liquid film, and the fuel liquid film is sheared / split.
The particle size of the liquid fuel is finely atomized and sprayed toward the combustion air from the outlet of the atomized fuel injection hole. Therefore, in the atomized state, the degree of uniform mixing of the fuel and the vapor is increased, and the NOx is reduced and the NOx is reduced. It is possible to achieve smoke.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. FIGS. 1 (b), 2 and 3 show cross sections of the nozzle portion of the gas turbine combustor. In the figure, reference numeral 5 denotes a fuel nozzle, reference numeral 21 denotes a liquid fuel supply pipe, reference numeral 30 denotes a nozzle body which is arranged concentrically with the liquid fuel supply pipe, and reference numeral 50 denotes an air supply pipe. In addition, 51s is a combustion air flow path, 52 is an air swirler arranged in the air flow path, 40 is a steam flow path, 11 is a combustion chamber, and arrow Ag indicates a working gas flow direction of the gas turbine. ing.

FIG. 1 (a) schematically shows a gas turbine employing this combustor, wherein 200 is its combustor, 100 is an air compressor, and 300 is a turbine.
The high-pressure air 110 compressed by the air compressor 100 is introduced into the combustor 200, mixes and burns with the fuel supplied from the fuel system 201, and becomes a high-temperature and high-pressure combustion gas 210 and is introduced into the turbine 300. The gas turbine obtains an output from the generator 400 by converting the amount of work generated when the high-pressure and high-temperature combustion gas 210 undergoes adiabatic expansion into a shaft rotation force in the turbine 300.

In a general liquid fuel-fired gas turbine combustor, for example, as shown in FIG.
After the air extracted from the high-pressure air 110 compressed at 0 is cooled by the cooler 1, the pressure is increased by the fuel-spray air compressor 3 connected to the turbine shaft 2 via a gear.
The liquid fuel 7 supplied from the fuel supply device 6 is atomized / atomized at the fuel nozzle 5 by using the momentum of the fuel nozzle 5.

The steam 9 introduced from an exhaust heat recovery boiler 500 that generates steam using the exhaust heat of the gas turbine 9
Is preliminarily mixed into the airflow 10 introduced into the combustor, thereby lowering the flame temperature in the combustion chamber 11 and reducing the emission of NOx and smoke.

Referring back to FIG. 1, the fuel nozzle of the combustor according to the present invention has a nozzle body 30 disposed on the outer periphery of a liquid fuel supply pipe 21 having a plurality of fuel injection holes 20 at its end. A vapor passage 40 is formed between the nozzle body 30 and the liquid fuel supply pipe 21. Further, on the downstream side of the nozzle body 30, the wall 5a, that is, the vapor passage 40 is directed outward. A wall having a plurality of spray fuel injection holes (mixed gas flow holes) 31 opened (with a predetermined inclination angle with respect to the gas turbine working gas direction) is provided.

An air supply pipe 50 is provided on the outer periphery of the nozzle body 30, and the nozzle body 30 and the air supply pipe 50 are provided.
In other words, a swirler 52 for swirling the combustion air 51 is provided between them, that is, in the combustion air flow passage 51s.

The liquid fuel 7 introduced into the fuel nozzle 5 is
The fuel is injected from the fuel injection hole 20 at the end of the liquid fuel supply pipe 21 toward the inlet 32 of the spray fuel injection hole 31 (in the direction of the working gas Ag), and a fuel liquid film is formed on the inner wall of the spray fuel injection hole 31. You. Thereafter, the steam 9 flowing through the steam flow path 40 flows into the spray fuel ejection holes 31, and the momentum of the steam flow is transmitted to the fuel liquid film, and the fuel liquid film is sheared / split, whereby the particle diameter of the liquid fuel is reduced. Is atomized finely, and is sprayed toward the combustion air 51 from the outlet 33 of the fuel spray hole 31.

At this time, in the conventional method in which the steam 9 shown in FIG. 9 is mixed into the combustion air 10 in advance, the spray fuel 34 ejected from the spray fuel ejection hole 31 is faster than the combustion air 53 containing steam. Therefore, the spray fuel 34 is not well mixed with the combustion air 53 containing steam and the combustion chamber 11
, The local increase in the flame temperature in the combustion chamber could not be suppressed, and it was difficult to reduce the emissions of NOx and smoke. However, the present invention solves this brilliantly.

That is, according to the present invention, since the atomization of the liquid fuel is performed by using the momentum of the steam, the liquid fuel and the steam are effectively and uniformly mixed, and therefore, the locality in the combustion chamber 11 is reduced. Flame temperature rise is suppressed and NO
It is possible to effectively reduce x and smoke emissions.

The fuel nozzle described in the above embodiment is
The liquid fuel is sprayed / atomized using a vapor flow. If the nozzle satisfies the above-described components, the liquid fuel is sprayed or atomized.
Alternatively, it may have a structure as shown in FIG. That is,
The fuel injection direction is not always limited to the downstream direction (the working gas flow direction), but may be formed so as to be injected in the nozzle radial direction, and the mist fuel injection hole 31 may be arranged downstream. .

Further, the gas turbine having the fuel nozzle described in the embodiment of the present invention may have a system configuration as shown in FIG. In this configuration, as shown in the conventional configuration of FIG. 9, it is not necessary to install the fuel spray air compressor 3 which is a factor of reducing the shaft output of the gas turbine. Is possible.
Furthermore, since the conventional two lines of steam piping and fuel spray air piping can be combined into one system as fuel spray steam piping, the piping system can be simplified, reliability is improved, and manufacturing costs are reduced. It is possible.

Further, the gas turbine provided with the fuel nozzle described in the embodiment of the present invention may have a system configuration as shown in FIG. This is a configuration in which the liquid fuel 7 is sprayed using steam from the separately provided steam generator 8 in the entire operation range from the start of the gas turbine to the rated load.

Thus, the steam flow rate can be individually controlled with respect to the load of the gas turbine, so that the emission of NOx and smoke can be effectively reduced in the entire operation of the gas turbine. Further, in the present system, the installation of the fuel spray air compressor 3 which is a factor of reducing the shaft output of the gas turbine as in the conventional configuration is not required, so that the shaft output of the gas turbine can be increased. is there.

Further, since the conventional two pipes of the steam pipe and the fuel spray air pipe can be integrated into one system as the fuel spray steam pipe, the pipe system can be simplified, the reliability is improved, and the manufacturing cost is improved. Can be reduced.

Further, the gas turbine having the fuel nozzle described in the embodiment of the present invention may have a system configuration as shown in FIG. This means that the steam 9 generated by the exhaust heat recovery boiler 500 installed downstream of the gas turbine or a separately installed steam generator not shown is supplied to the fuel spray air in the entire operation range from the start of the gas turbine to the rated load. The structure is such that the fuel 4 is mixed with the fuel spray air 4 pressurized by the compressor 3 in the mixer 60, and the liquid fuel 7 is sprayed / atomized by using the mixture 61.

Thus, compared to the conventional structure of FIG. 9 in which the liquid fuel is sprayed only by the fuel spray air, the fuel spray air 4 is sprayed.
Since the amount of supply of the fuel spray air 4 can be reduced by the amount of mixing the steam 9 with the steam, the capacity of the fuel spray air compressor 3 which is a factor of reducing the shaft output of the gas turbine can be reduced. It is possible to increase the gas turbine shaft power.

As described above, in the gas turbine combustor formed as described above, the liquid fuel is sprayed / sprayed by using the steam flow or the mixture of the fuel spray air and the steam.
By atomization, the degree of mixing of fuel and steam is increased, the flame temperature in the combustion chamber is effectively reduced, and low NOx
It is possible to achieve low smoke and low smoke.

[0027]

As described above, according to the present invention, the atomization of liquid fuel and the uniform mixing degree of fuel and steam can be increased by using a simple structure without using a special device. This type of gas turbine combustor that can achieve low NOx and low smoke can be obtained.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view showing one embodiment of a gas turbine provided with a gas turbine combustor of the present invention and a gas turbine combustor.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 1;

FIG. 4 is a vertical sectional side view showing another embodiment of the gas turbine combustor (main part) of the present invention.

FIG. 5 is a vertical sectional side view showing another embodiment of the gas turbine combustor (main part) of the present invention.

FIG. 6 is a configuration example of a gas turbine provided with the gas turbine combustor of the present invention.

FIG. 7 is a configuration example of a gas turbine including the gas turbine combustor of the present invention.

FIG. 8 is a configuration example of a gas turbine including the gas turbine combustor of the present invention.

FIG. 9 is a configuration diagram of a conventional liquid fuel-fired gas turbine.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cooler, 3 ... Air compressor for fuel spraying, 6 ... Fuel supply device, 7 ... Liquid fuel, 8 ... Steam supply device, 9 ... Steam flow, 11 ... Combustion chamber, 20 ... Fuel injection hole, 20a ... Liquid fuel Supply unit, 21: liquid fuel supply pipe, 30: nozzle body,
31: spray fuel injection hole, 40: steam flow path, 40a: steam supply unit, 50: air supply pipe, 51: combustion air, 51a ...
Air supply unit, 51s: combustion air flow passage, 60: mixer of steam and fuel spray air, 61: mixed air flow of steam and fuel spray air, 100: air compressor, 300: turbine,
400: generator, 500: waste heat recovery boiler.

Claims (5)

[Claims] 1. A liquid fuel supply unit for supplying liquid fuel in a spray form, an air supply unit for supplying combustion air, and a steam supply unit for supplying steam, wherein the liquid fuel and the combustion air are supplied. And a gas turbine combustor configured to mix and burn the steam, wherein a wall provided with a mixed gas flow hole through which a mixed gas of the spray liquid fuel and the steam flows is provided on a front surface of the spray of the spray liquid fuel. A gas turbine combustor, wherein a body is provided, and a discharge-side end of the mixed gas flow hole is formed to open to a flow passage of the combustion air. 2. A liquid fuel supply unit for supplying liquid fuel in a spray form, an air supply unit for supplying combustion air, and a vapor supply unit for supplying steam, wherein the liquid fuel and the combustion air are supplied. And a gas turbine combustor configured to mix and burn the steam, wherein a steam flow path of the steam supply unit is provided around a liquid fuel nozzle of the liquid fuel supply unit, and the air supply is provided around an outer periphery thereof. A portion having a combustion air flow path is provided, and a wall having a mixed gas flow hole is provided on the front side in the injection direction of the liquid fuel nozzle, and the spray liquid fuel and vapor are flowed through the mixed gas flow hole, and A gas turbine combustor characterized in that both gas mixtures are injected into the combustion air flow passage. 3. A liquid fuel supply unit for supplying liquid fuel in a spray form, an air supply unit for supplying combustion air, and a vapor supply unit for supplying steam, wherein the liquid fuel and the combustion air are supplied. And a gas turbine combustor configured to mix and burn the steam, wherein a steam flow path of the steam supply unit is provided around a liquid fuel nozzle of the liquid fuel supply unit, and the air supply is provided at an outer peripheral portion thereof. The combustion air flow path of the section is provided, and the ejection side opening of the steam flow path is opened at the ejection position of the liquid fuel ejected from the fuel ejection hole, and the liquid fuel ejected from the fuel ejection hole is opened. A wall having a fuel liquid film forming flow path is arranged at the ejection position, a liquid film of liquid fuel ejected from the fuel ejection hole is formed in the fuel liquid film forming flow path, and introduced from the vapor flow path. The liquid in the vapor stream Dividing / atomizing gas turbine combustor is characterized in that so as to spray the atomized liquid fuel into the combustion air. 4. The gas turbine combustor according to claim 1, wherein an injection direction of the liquid fuel of the liquid fuel supply unit is formed in the same direction as a working gas of the gas turbine combustor. 5. The gas turbine combustor according to claim 4, wherein the mixed gas flow hole provided in the wall is provided at a predetermined angle with respect to a liquid fuel injection direction.