CN1884910A - Burner, gas turbine burner, cooling method of burner and modification method of burner - Google Patents

Abstract

The invention provides a burner, a gas turbine combustor, and a burner cooling method. A burner (13) for injecting a gaseous fuel (201) containing at least either hydrogen or carbon monoxide into a combustion chamber of a burner (3) according to the present invention comprises: a starting fuel nozzle (15) for injecting liquid fuel (200) into the combustion chamber; a mixed fuel injection nozzle (16) which is provided around the nozzle and injects a gas fuel; an air swirler (17) provided at an end portion of the nozzle, having a flow passage (17a) for injecting a part (102a) of compressed air from the air compressor (2) into the combustion chamber, and having a discharge hole (16a) of the mixed fuel nozzle (16) arranged at an inner circumferential portion of the flow passage (17 a); and a cooling hole (53) which is provided on a nozzle end surface (18) facing the combustion chamber and injects a part of the gaseous fuel injected from the mixed fuel nozzle into the combustion chamber.

Description

Burner, gas turbine burner, cooling method of burner and modification method of burner

technical field

The present invention relates to a burner using a mixed fuel containing at least either hydrogen or carbon monoxide, a gas turbine burner, a method for cooling the burner, and a method for rebuilding the burner.

Background technique

In recent years, fuels for gas turbines have been diversifying, and studies have been conducted on LNG (liquefied natural gas) or light oil, which is the main fuel for gas turbines, and mixed gaseous fuels composed of various components including hydrogen or carbon monoxide other than Type A heavy oil ( Hereinafter referred to as the use of mixed fuel). This mixed fuel has a higher flame temperature than LNG, especially hydrogen has a wide flammable range, fast burning speed and flammability.

When burning LNG, the pre-mixing method becomes the mainstream. However, if the mixed fuel is combusted in a premixed manner, flashback is likely to occur due to changes in characteristics due to changes in fuel composition or hydrogen or carbon monoxide contained in the mixed fuel. Therefore, it is difficult to combust the mixed fuel in a premixed manner. Therefore, when combusting mixed fuel, generally, a burner of a diffusion combustion method is used that injects fuel and air into a combustion chamber separately (see Patent Document 1: JP-A-2004-3730).

In the case of a mixed fuel containing hydrogen or carbon monoxide, it is necessary to consider the safety of gas turbine ignition even in diffusion combustion, and it is desirable to use other types of fuel such as light oil when starting the gas turbine. When using other types of fuel such as light oil to start the gas turbine, after starting, speeding up, and adding a load, the operating mode is switched from the starting fuel to the special combustion mixed fuel. The term "exclusively burning mixed fuel" here refers to an operation mode in which only the mixed fuel is supplied to the burner. However, after switching to the exclusive combustion of mixed fuel, since the flame temperature of the mixed fuel is high and the combustion speed is also fast, the flame is easy to approach the end surface of the nozzle, so there is a danger of the metal temperature on the end surface of the nozzle rising.

Contents of the invention

The object of the present invention is to provide a burner, a gas turbine burner, a method for cooling the burner, and a method for rebuilding the burner, which can be used even when a mixed fuel containing at least any one of hydrogen or carbon monoxide is used as the fuel. Under certain circumstances, the metal temperature on the end face of the nozzle can also be controlled within an appropriate range and its reliability can be improved.

(1) In order to achieve the above object, in the burner of the present invention that injects a mixed fuel containing at least any one of hydrogen or carbon monoxide into the combustion chamber of a gas turbine combustor, it is characterized in that: A starting fuel nozzle for starting fuel; a mixed fuel nozzle that is arranged around the starting fuel nozzle and injects the above-mentioned mixed fuel; is arranged at the end of the mixed fuel nozzle on the side of the combustion chamber, and has a an air circulator that arranges the spray holes of the mixed fuel nozzles on the inner circumference of the flow passages while injecting a part of the compressed air from the air compressor to the plurality of flow passages of the combustion chamber; A part of the mixed fuel injected from the mixed fuel nozzle is injected into the cooling hole of the combustion chamber facing the nozzle end surface of the combustion chamber, and in order to lower the flame temperature near the nozzle end surface.

(2) In the above (1), it is preferable that the starting fuel nozzle includes a liquid fuel nozzle installed to inject liquid fuel for starting the gas turbine; Spray air nozzles for spray air.

(3) In the above (1), it is more preferable that the starting fuel nozzle is disposed at a central portion in a radial direction of a main chamber liner forming the combustion chamber.

(4) In the above (1), it is preferable to further include an inert medium supply system for supplying the inert medium to the above-mentioned start-up fuel nozzle; The inert medium is supplied to the starting fuel nozzle; and the inert medium is injected near the end surface of the nozzle by the starting fuel nozzle.

(5) In the above (1), it is preferable that the mixed fuel is coke oven gas, blast furnace gas, converter gas, coal, gasification gas of heavy oil, or the like.

(6) In addition, in order to achieve the above object, in the gas turbine combustor burning a mixed fuel containing at least either hydrogen or carbon monoxide according to the present invention, it is characterized in that it includes: an outer cylinder as a pressure vessel; One side of the inner circumference of the barrel, and a main chamber liner forming a combustion chamber inside it; a burner for forming a flame in the above-mentioned combustion chamber in the main chamber liner; and passing the burner through to form a flame The resulting combustion gases are directed to the tailpiece of the turbine;

In addition, the burner includes: a starting fuel nozzle injecting starting fuel into the combustion chamber; a mixed fuel nozzle installed around the starting fuel nozzle and injecting the mixed fuel; The end portion of the combustion chamber side has a plurality of flow paths for injecting part of the compressed air from the air compressor into the combustion chamber in order to maintain the flame, and the injection hole of the above-mentioned mixed fuel nozzle is arranged in the flow path. an air circulator on the inner peripheral portion of the passage; and a nozzle end surface facing the above-mentioned combustion chamber, and injecting a part of the mixed fuel injected from the above-mentioned mixed fuel nozzle into the above-mentioned combustion chamber in order to reduce the flame temperature near the nozzle end surface cooling holes.

(7) Furthermore, in order to achieve the above object, in the method for cooling a burner of a diffusion combustion method in which a mixed fuel containing at least either hydrogen or carbon monoxide is injected into a combustion chamber of a gas turbine combustor according to the present invention, the It is characterized in that by providing a cooling hole for spraying a part of the mixed fuel on the nozzle end surface facing the combustion chamber, and injecting the mixed fuel into the combustion chamber through the cooling hole, thereby reducing the flame temperature near the nozzle end surface, Thereby, the rise of the metal temperature on the nozzle end face is controlled.

(8) Furthermore, in order to achieve the above object, in the burner of the present invention that injects a mixed fuel containing at least any one of hydrogen or carbon monoxide into the combustion chamber of a gas turbine combustor, it is characterized in that: A starting fuel nozzle consisting of a liquid fuel nozzle for injecting liquid fuel for starting into the above-mentioned combustion chamber and a spray air nozzle arranged around the liquid fuel nozzle and spraying spray air for atomizing the liquid fuel; Around the start-up fuel nozzle, the mixed fuel nozzle that injects the above-mentioned mixed fuel; it is installed at the end of the above-mentioned combustion chamber side of the mixed fuel nozzle, and injects a part of the compressed air from the air compressor to maintain the flame. an air gyrator of the above-mentioned combustion chamber; and an inert medium supply system for supplying an inert medium to the above-mentioned start-up fuel nozzle; The fuel nozzle is used, and the inert medium is sprayed near the end face of the nozzle using the above-mentioned starting fuel nozzle.

(9) In addition, in order to achieve the above object, in the gas turbine combustor burning a mixed fuel containing at least any one of hydrogen or carbon monoxide according to the present invention, it is characterized in that it includes: an outer cylinder as a pressure vessel; One side of the inner circumference of the barrel, and a main chamber liner forming a combustion chamber inside it; a burner for forming a flame in the above-mentioned combustion chamber in the main chamber liner; and passing the burner through to form a flame The resulting combustion gases are directed to the tailpiece of the turbine;

In addition, the burner includes: a liquid fuel nozzle for injecting liquid fuel for starting the gas turbine into the combustion chamber; A starting fuel nozzle composed of an air nozzle; a mixed fuel nozzle that is arranged around the starting fuel nozzle and injects the above-mentioned mixed fuel; is arranged at the end of the mixed fuel nozzle on the side of the combustion chamber, and has a an air gyrator that injects part of the compressed air from the air compressor into the combustion chamber; and an inert medium supply system that supplies the inert medium to the fuel nozzle for starting the above; The inert medium from the inert medium supply system is supplied to the priming fuel nozzle, and the inert medium is injected near the end surface of the nozzle by the priming fuel nozzle.

(10) Furthermore, in order to achieve the above object, in the method of cooling a burner of a diffusion combustion method in which a mixed fuel containing at least either hydrogen or carbon monoxide is injected into a combustion chamber of a gas turbine combustor according to the present invention, the It is characterized in that a mixed fuel nozzle for injecting the above-mentioned mixed fuel is provided around the start-up fuel nozzle for injecting the start-up fuel to the above-mentioned combustion chamber; when the special combustion operation of the above-mentioned mixed fuel is performed, the inertness from the above-mentioned inert medium supply system The medium is supplied to the start-up fuel nozzle, and the inert medium is sprayed near the end face of the nozzle by the fuel nozzle for start-up, thereby reducing the flame temperature near the end face of the nozzle, thereby controlling the rise of the metal temperature on the end face of the nozzle.

(11) Furthermore, in order to achieve the above object, the burner for injecting a mixed fuel containing at least any one of hydrogen or carbon monoxide into the combustion chamber of a gas turbine combustor according to the present invention is characterized in that: A starting fuel nozzle that injects fuel into the above-mentioned combustion chamber; a mixed fuel nozzle that is arranged around the starting fuel nozzle and injects the above-mentioned mixed fuel; an air gyrator for arranging the injection holes of the above-mentioned mixed fuel nozzle on the inner circumference of the above-mentioned flow passage while injecting a part of the compressed air from the air compressor to the plurality of flow passages of the above-mentioned combustion chamber while maintaining the flame; And the mechanism for purging fuel from the above starter fuel nozzles.

(12) In the above (11), it is preferable that the means for purging the fuel includes a system for supplying a part of the mixed fuel supplied to the mixed fuel nozzle to the starting fuel nozzle.

(13) In addition, in order to achieve the above object, in the burner of the present invention that injects a mixed fuel containing at least any one of hydrogen or carbon monoxide into the combustion chamber of the gas turbine combustor, it is characterized in that it has a The swirler of the chamber, the above-mentioned combustion chamber is equipped with: a starting fuel nozzle that injects starting fuel into the above-mentioned combustion chamber; a mixed fuel nozzle that is arranged around the starting fuel nozzle and injects the above-mentioned mixed fuel; The end portion of the fuel nozzle on the side of the combustion chamber has a part of the compressed air from the air compressor injected into the plurality of flow channels in the combustion chamber in order to maintain the flame, and the injection hole of the above-mentioned mixed fuel nozzle The air swirler disposed on the inner peripheral portion of the flow passage; and a mechanism for lowering the flame temperature near the swirler facing the combustion chamber below the melting point of the swirler member.

(14) Furthermore, in order to achieve the above object, in the modification method of the burner of the present invention, which injects a mixed fuel containing at least any one of hydrogen or carbon monoxide into the combustion chamber of the gas turbine combustor, it is characterized in that the injection The burner is equipped with: a start-up nozzle consisting of a liquid fuel nozzle for injecting liquid fuel for starting the gas turbine into the above-mentioned combustion chamber, and a spray air nozzle installed around the liquid fuel nozzle and spraying spray air for atomizing the liquid fuel. a fuel nozzle; a mixed fuel nozzle which is arranged around the start-up fuel nozzle and injects the above-mentioned mixed fuel; A part of the compressed air is sprayed into multiple flow channels of the above-mentioned combustion chamber; on the above-mentioned burner, a mechanism for supplying an inert medium to the above-mentioned spray air nozzle is also added.

According to the present invention, even when a mixed fuel containing at least either hydrogen or carbon monoxide is used as the fuel, the flame temperature can be lowered by increasing the fuel concentration near the nozzle end face, so that the metal temperature of the nozzle end face can be controlled within the appropriate range and improve its reliability. In addition, by supplying the inert medium near the nozzle end surface, the metal temperature on the nozzle end surface can also be controlled within an appropriate range.

Description of drawings

FIG. 1 is a schematic diagram of a gas turbine plant including a burner according to a first embodiment of the present invention.

Fig. 2 is an enlarged side cross-sectional view of the burner according to the first embodiment of the present invention.

Fig. 3 is a front view of the burner according to the first embodiment of the present invention seen from the combustion chamber side.

Fig. 4 is a partially enlarged view of a burner according to a second embodiment of the present invention.

Fig. 5 is a front view of a burner according to a second embodiment of the present invention seen from the combustion chamber side.

6 is a schematic diagram of a gas turbine plant including a burner according to a second embodiment of the present invention.

Fig. 7 is a graph showing the relationship between the mass ratio of fuel to air and the theoretical combustion temperature of a mixed gas composed of hydrogen, methane, and nitrogen.

Fig. 8 is a graph showing the relationship between the supply of spray air or inert medium and the metal temperature on the end surface of the nozzle after switching to the mixed fuel only combustion operation.

Fig. 9 is a diagram showing a cleaning system for cleaning liquid fuel stagnated inside the priming nozzle.

Detailed ways

Embodiments of the present invention will be described below using the drawings.

FIG. 1 is a schematic diagram of a gas turbine plant including a burner according to a first embodiment of the present invention.

The gas turbine plant of the present embodiment includes an air compressor 2, a combustor 3, a turbine 4, a generator 6, a starter motor 8 for driving the gas turbine, and the like. In the air compressor 2 , the sucked air 101 is compressed, and the compressed air 102 from the air compressor 2 is burned by the combustor 3 together with fuels 200 and 201 . When the combustion gas 110 from the combustor 3 is supplied to the turbine 4 , the turbine 4 can obtain rotational power from the combustion gas 110 , and the rotational power of the turbine 4 is transmitted to the air compressor 2 and the generator 6 . The rotational power transmitted to the air compressor 2 is used as compression power, and the rotational power transmitted to the generator 6 is converted into electrical energy.

In addition, in FIG. 1, although the generator 6 is shown in figure as a load apparatus, a pump etc. may be used as a load apparatus. In addition, the use of the turbine 4 is not limited to a single-shaft type, and a double-shaft type may be used.

The burner 3 of the present embodiment is used to burn a multi-component mixed gas fuel (mixed fuel) containing at least any one of hydrogen (H ₂ ) or carbon monoxide (CO). In addition to the gas fuel 201 as this mixed fuel, It also includes a supply system for supplying liquid fuel 200 which is the starting fuel of the gas turbine, atomizing air 103 for atomizing the liquid fuel 200 , and an inert medium (steam) 104 required for reducing _NOx . The gaseous fuel 201 combusted by the burner 3 includes, for example, a gaseous fuel composed of various components such as coke oven gas, blast furnace gas, and converter gas, or gaseous gas containing hydrogen or gas obtained by gasifying raw materials such as coal and heavy oil with oxygen. Carbon monoxide coal, heavy oil gasification gas, etc. In addition, as the liquid fuel 200, light oil, type A heavy oil, etc. are used, for example.

The burner 3 is equipped with: an outer cylinder 10 as a pressure vessel; a main chamber liner 12 which is arranged on the inner circumference of the outer cylinder 10 and forms a combustion chamber inside; A burner 13 for forming a flame; the combustion gas 110 generated by the flame formed by the burner 13 is guided to a transition piece (not shown) of the turbine 4 . In this embodiment, the burners 13 adopt a diffusion combustion method, and are arranged one-to-one on each burner pot.

FIG. 2 is an enlarged side cross-sectional view of the burner 13, and FIG. 3 is a front view of the burner 13 seen from the combustion chamber side.

As shown in these FIGS. 2 and 3 , the burner 13 includes: a starting fuel nozzle 15 that injects a liquid fuel 200 , which is a starting fuel, into the combustion chamber; a mixed fuel nozzle 16 that injects a gaseous fuel 201 ; An air gyrator 17 that injects a part of the compressed air 102 a from the air compressor 2 to the combustion chamber.

The starting fuel nozzle 15 consists of a liquid fuel nozzle 20 which injects a liquid fuel 200 for starting the gas turbine, which is arranged at the center in the radial direction of the combustion chamber, and a spray air nozzle which injects spray air 103 for atomizing the liquid fuel 200. 21 constitute. The spray air nozzle 21 is formed by an inner tube 22 provided to surround the periphery of the liquid fuel nozzle 20, and the spray air 103 or steam 104 flows through a flow path formed between the inner wall surface of the inner tube 22 and the outer wall surface of the liquid fuel nozzle 20. . And, the spray air 103 or the inert medium (steam) 104 sprayed from the discharge port 21a of the spray air nozzle 21 facing the combustion chamber interferes with the liquid fuel 200 sprayed from the discharge port 20a of the liquid fuel nozzle 20, thereby, The liquid fuel 200 is atomized and sprayed into the combustion chamber.

The mixed fuel nozzle 16 has a casing 23 provided to surround the spray air nozzle 21 as a main body, and the flow path of the gaseous fuel 201 is formed between the inner wall surface of the casing 23 and the outer wall surface of the inner cylinder 22 of the spray air nozzle 21. flow through. An air swirler 17 is provided at an end portion of the fuel mixture nozzle 16 on the combustion chamber side. As shown in FIGS. 2 and 3 , the air swirler 17 has flow paths 17 a for supplying swirling components to the compressed air 102 a at regular intervals in the circumferential direction. The flow path 17a is provided similarly to the outer peripheral portion of the casing 23 on the combustion chamber side. A part of the compressed air 102 from the air compressor supplied to the combustor 3 , that is, air 102 a supplied by pressure balance, is supplied to the flow path 17 a of the air gyrator 17 . The rest of the compressed air 102 passes into the combustion chamber through the combustion air holes or cooling holes of the main chamber liner 12 . Therefore, the cooling of the main chamber liner 12 can also be performed simultaneously by using the compressed air from the air compressor 2 .

The injection port 16a of the mixed fuel nozzle 16 is provided on the inner peripheral side of the flow path 17a of the air swirler 17, and the gaseous fuel 201 ejected from the ejection port 16a is ejected to the combustion chamber along with the swirling flow ejected from the air swirler 17. indoor. Also, the flame can be kept in front of the air gyrator 17 by the swirling air 102 a from the air gyrator 17 mixing with the gaseous fuel 201 .

Cooling holes 53 are provided on the nozzle end surface (swirler end surface) 18 of the combustion chamber facing the burner 13. The area is multiplied so that it communicates with the passage of the mixed fuel nozzle 16 . And, a part of the gaseous fuel 201 a of the gaseous fuel 201 injected from the mixed fuel nozzle 16 is injected into the combustion chamber through these cooling holes 53 . As a result, the fuel concentration in the vicinity of the nozzle end surface 18 is increased.

In the present embodiment, a starting fuel supply system for supplying the liquid fuel 200 to the starting fuel nozzle 15 and a mixed fuel supply system for supplying the gaseous fuel 201 to the mixed fuel nozzle 16 are independently provided. The starting fuel supply system is connected to the introduction port 20b of the liquid fuel nozzle 20, and the mixed fuel supply system is connected to the introduction port 16b of the mixed fuel nozzle 16, and each has a control valve (not shown) for adjusting the fuel flow rate.

On the other hand, a spray air supply system for supplying spray air 103 to the spray air nozzle 21 is connected to the introduction port 21b of the spray air nozzle 21, and an inert medium supply system for supplying the inert medium 104 to the air gyrator 17 is connected to the burner outer cylinder. 10 on the introduction port 10b. The spray air supply system and the inert medium supply system are connected to each other through a bypass line, and a stop valve 300 for opening and closing the flow path of the bypass line is provided on the bypass line connecting the two. In addition, on the downstream side of the bypass line of the inert medium supply system, a shut-off valve 301 for opening and closing the flow path of the inert medium supply system and adjusting the steam flow through the inert medium supply system are provided in the following order from the upstream side. Flow rate of the steam flow regulator valve 302 .

In the gas turbine plant with the above-mentioned structure, the gas turbine is driven by external power such as the starter motor 8 when starting, and the air 102 and liquid fuel 200 discharged from the air compressor 2 are ignited in the burner. The combustion gas 110 from the combustor 3 is supplied to the turbine 4 to provide rotational power to the turbine 4 . As the flow rate of the liquid fuel 200 increases, the speed of the turbine 4 is increased, and the starter motor 8 is disengaged to switch to the independent operation of the gas turbine. Furthermore, once the no-load rated speed is reached, the generator 6 is incorporated, and the flow rate of the liquid fuel 200 is further increased to raise the inlet gas temperature of the combustion turbine 4 and increase the load.

After incorporating the load, steam is injected from the inert medium supply system to the burner 3 to control the emission of _NOx . The steam 104 supplied to the burner 3 passes through the cut-off valve 301 and is adjusted to an appropriate flow rate by the steam flow regulating valve 302 , then mixes with the combustion air 102a from the air compressor 2 and is ejected from the flow channel 17a of the air gyrator 17 to the combustion chamber. The oxygen concentration of the combustion air 102a is reduced by mixing with steam. Thus, by burning the liquid fuel 200 with air having a low oxygen concentration, the flame temperature in the combustion chamber is lowered and the _NOx concentration is controlled.

Thereafter, when the operation of raising the load is performed, the fuel switching operation of switching from the liquid fuel 200 to the mixed gas fuel, that is, the gas fuel 201 may be performed. The fuel switching operation is performed by reducing the flow rate of the liquid fuel 200 and increasing the supply amount of the gaseous fuel 201 while keeping the load of the gas turbine constant. When the fuel switching operation to the gaseous fuel 201 is finally completed and the fuel is switched to the mixed fuel only combustion operation, the load can be increased with the increase of the gaseous fuel 201 . After switching to the mixed fuel only combustion operation, along with the stop of the supply of the liquid fuel 200 , the supply of the spray air 103 for atomizing the liquid fuel 200 is stopped.

Here, in the burner for diffusion combustion as in this embodiment, in order to atomize the starting fuel, air is usually injected from the nozzle end surface on the combustion chamber side of the burner. However, the supply of such air has a large influence on the metal temperature at the end surface of the nozzle when the multi-component mixed gas is combusted. Next, the reason for this will be described with reference to FIGS. 7 and 8 .

Fig. 7 is a graph showing the relationship between the fuel-air mass ratio (F/A) and the theoretical combustion temperature of a mixed gas composed of hydrogen, methane, and nitrogen.

As shown in Figure 7, the theoretical combustion temperature (°C) has the following trend: it rises with the increase of F/A (kg/kg), and reaches the maximum value under a certain F/A condition. If the F/A is further increased , then decreases. The F/A at the maximum theoretical combustion temperature is called the stoichiometric mixture ratio, and the region where the F/A is low is called the fuel-lean region, and the state where the F/A is high is called the fuel-rich state. area. When considering the relationship between the fuel rich area and F/A, it can be considered that when the spray air is supplied (area A in Figure 7) than when the spray air is not supplied (area B in Figure 7), it is closer to the quantity theory mixing ratio.

In the case of the present embodiment, the vicinity of the nozzle end surface of the burner 3 is considered to be a fuel-rich region, but by supplying spray air, F/A approaches the stoichiometric mixing ratio, and the flame temperature (combustion temperature) increases. On the other hand, when an inert medium such as steam is supplied, the theoretical combustion temperature tends to decrease (region C in FIG. 7 ).

Fig. 8 is a graph showing the correlation between the supply of spray air or inert medium and the metal temperature at the end face of the nozzle after shifting to the mixed-fuel combustion operation.

What Fig. 8 shows is the situation of burning the mixed gas of hydrogen, methane and nitrogen. As shown in the figure, the temperature of the metal has nothing to do with the load conditions of the gas turbine, and it is higher when the spray air is supplied than when no air is supplied; while it is lower when the inert medium is supplied than when the inert medium is not supplied. This is considered to be because the F/A near the nozzle end surface changes depending on whether the spray air or the inert medium is supplied, and the combustion temperature changes. In particular, in the case of fuel containing hydrogen or carbon monoxide, the flame tends to approach near the end face of the nozzle due to the high combustion speed, and therefore, the metal temperature is easily affected by the flame temperature. Therefore, as in the present embodiment, when combusting a mixed fuel containing hydrogen or carbon monoxide, the metal temperature rise at the nozzle end surface can be controlled by taking care that the F/A near the nozzle end surface does not reach a condition near the stoichiometric mixture ratio.

In the case of the present embodiment, when the nozzle end surface is cooled by a part of the air discharged from the air compressor, the F/A approaches the stoichiometric mixing ratio and the flame temperature increases. Therefore, when burning a mixed fuel containing hydrogen or carbon monoxide, the flame is close to the swirler and the temperature of the metal tends to rise, making it difficult to cool it by air. On the other hand, under rated load conditions, when the F/A near the nozzle end surface is set in the fuel-lean region by increasing the amount of air supplied to the air gyrator 17, etc., under low load conditions in which the fuel flow rate is reduced, due to Unburned components increase and it is easy to extinguish the flame, so it is not practical. Conversely, when the F/A near the nozzle end surface is increased by extremely controlling the amount of air supplied to the air gyrator 17, since the fuel rich region is further reached than the combustible range, problems with combustion stability such as flame blowout occur. question.

In contrast, in the present embodiment, the fuel concentration at the nozzle end surface is increased by providing the cooling hole 53 on the nozzle end surface through which a part of the mixed gas fuel 201 is discharged. Therefore, the F/A in the vicinity of the nozzle end surface can be increased, and the flame temperature in the vicinity of the nozzle end surface can be reduced. Therefore, it is possible to reduce the temperature of the metal on the nozzle end surface without causing a phenomenon in which F/A shifts to the vicinity of the stoichiometric mixing ratio to increase the flame temperature as in air cooling.

In addition, the temperature of the fuel supplied to the gas turbine varies somewhat depending on the type of fuel, among which coke oven gas and the like are below 100°C, and gaseous fuels that gasify coal with oxygen are also below 200 to 300°C. The temperature of the air discharged from the air compressor (about 390°C) is even lower. Thus, by utilizing the sensible heat of the fuel, it is possible to ensure high cooling performance even compared with air cooling. In this way, in the working load range of the gas turbine, since the temperature of the metal on the nozzle end surface can be controlled within an appropriate range while ensuring combustion stability, reliability can be improved.

Furthermore, according to the present embodiment, by providing the discharge hole 16a of the gaseous fuel 201 on the inner peripheral side of the flow path 17a of the air gyrator 17, the discharge hole 16a is subjected to the dynamic pressure of the air 102a. Therefore, during the combustion operation of the liquid fuel 200, the compressed air 102a from the air compressor 2 is supplied into the fuel nozzle 16 through the discharge hole 16a, and the air 102a is supplied through the cooling hole 53 provided on the end surface of the nozzle. At this time, since the sprayed liquid fuel 200 is mixed with the air 102a supplied from the cooling hole 53, more air is released for starting than the case where the liquid fuel 200 is only mixed with the air 102a supplied from the air gyrator 17. Since it is supplied to the vicinity of the fuel nozzle 50, soot control during liquid fuel combustion can be effectively performed.

In general, liquid fuel is burned through processes such as atomizing the liquid fuel, evaporating the atomized fuel, mixing the fuel and air, and burning. Therefore, when the mixing of fuel and air is insufficient, the concentration of soot such as soot increases during combustion. In the present embodiment, the spray air 102a can be supplied through the cooling hole 53 for spraying the gaseous fuel 201 from the vicinity of the spray housing (spray hole 21a ) that atomizes and sprays the starting liquid fuel. By burning the liquid fuel in this way, the effect of controlling the generation of soot can be obtained at the same time.

In addition to the above, in this embodiment, by opening the shutoff valve 300, a part of the inert medium 104 such as steam used for reducing _NOx can be supplied to the spray air supply system of the starting fuel nozzle 15. The steam 104 required for _NOx reduction is supplied after switching to the combustion operation of the gaseous fuel 201 and stopping the supply of the spray air 103 . By spraying steam 104 from the starting fuel nozzle 15 located at the center of the nozzle end face, the flame temperature near the nozzle end face is lowered (see also FIG. 7 ), thereby reducing the metal temperature on the nozzle end face.

In addition, when the steam 104 is supplied to the starting fuel nozzle 15, it is necessary to provide a check valve for preventing the steam 104 from flowing backward in the spray air supply system. In this embodiment, the case of using steam as an inert gas for reducing NO _x has been described as an example, but in general, other inert media such as nitrogen or carbon dioxide obtained in factories can also be used. Also in this case, the same effect can be obtained.

Also, after the liquid fuel 200 is burned, by using the supply system of the spray air 103a as the supply system of the inert medium and injecting the inert medium from the starting fuel nozzle 15, it is possible to supply oil, spray air, Gas triple fuel structure.

In the present embodiment, both the structure in which the gaseous fuel 201 is sprayed from the cooling hole 53 and the structure in which the inert medium is sprayed from the spray air supply system of the starting fuel nozzle 15 are provided, but either one may be used. Get higher cooling effect. When omitting the cooling function of the nozzle end surface by spraying the inert medium from the center of the nozzle end surface, for example, the shutoff valve 300 and the bypass line provided with the shutoff valve 300 may be omitted. On the contrary, even if the cooling function of spraying the mixed fuel from the cooling hole 53 is omitted, the cooling effect of the nozzle end surface can be obtained by spraying the inert medium from the center of the nozzle end surface.

Here, FIG. 4 is a partially enlarged view of a burner according to a second embodiment of the present invention, in which the cooling hole 53 of this embodiment is omitted, and FIG. 5 is a front view of the burner seen from the combustion chamber side. . In these figures, the same reference numerals are assigned to the same parts as those in the previous figures, and description thereof will be omitted.

The burner shown in FIGS. 4 and 5 is provided with a spray hole 16 a on the inner peripheral side of a flow path 17 a of the air swirler 17 , and is equipped with a starting fuel nozzle 15 at the radial center of the air swirler 17 . Except that the cooling hole 53 is omitted, it has the same structure as the burner shown in FIGS. 2 and 3 . In this way, even a burner that does not have such a cooling hole and cannot increase the fuel concentration in the vicinity of the nozzle end surface 18 can control the increase in the metal temperature of the nozzle end surface 18 .

Fig. 6 is a schematic diagram of a gas turbine plant including the burner according to the second embodiment of the present invention shown in Figs. 4 and 5 .

In the gas turbine plant shown in FIG. 6 , as in the plant shown in FIG. 1 , a gas fuel 201 consisting of a multi-component gas containing hydrogen or carbon monoxide, a liquid fuel 200 as a starting fuel for the gas turbine, and a Spray air 103 for atomizing liquid fuel 200 and steam 104 for _NOx reduction. Like the complete set of equipment in Fig. 1, there is a stop valve 301 and a flow regulating valve 302 in the inert medium supply system, and a stop valve 300 is provided in the bypass line connecting the spray air supply system and the inert medium supply system. That is, the gas turbine plant according to the present embodiment has almost the same structure as the plant shown in FIG. 1 except that the cooling hole on the nozzle end face is omitted.

The plant of this embodiment is also the same as the plant of FIG. 1 , by injecting the steam 104 into the combustion chamber after incorporating the load with the liquid fuel 200 , thereby reducing the concentration of NO _x . Then, the fuel is switched from the liquid fuel 200 to the gaseous fuel 201 as the load increases thereafter, and the supply of the spray air 103 is stopped after the operation mode shifts to mixed fuel only combustion. After the supply of the spray air 103 is stopped, the shutoff valve 300 is opened and the steam 104 is sprayed from the center of the end face of the fuel nozzle 15 for starting. By supplying steam 104 to the combustion chamber from the starting fuel nozzle 15 located at the center of the end surface of the air gyrator 17, the temperature of the flame formed near the nozzle end surface can be lowered, and the temperature of the metal on the nozzle end surface can be lowered to improve reliability. .

In addition, since the steam 104 is supplied to the starting fuel nozzle 15 using the spray air supply system, it is not necessary to provide a new supply system for supplying the inert medium to the starting fuel nozzle 15 . In general, since there are no cooling holes for injecting fuel on the nozzle end surface, it is also a great advantage that the burner of the present embodiment can be easily configured by using a conventional diffusion combustion type burner.

9 is a schematic diagram of a gas turbine plant including a burner according to a third embodiment of the present invention.

In the first and second embodiments, the liquid fuel 200 is used to start the gas turbine, and the supply of the liquid fuel 200 is stopped after switching to the mixed-fuel exclusive combustion operation within a certain load range. At this time, if the liquid fuel 200 stays in the liquid fuel nozzle 20, the temperature of the nozzle 20 is raised by heat from the flame, and the stagnant liquid fuel 200 solidifies in the nozzle (caking). Therefore, after switching to the mixed fuel only combustion operation, by supplying gas such as nitrogen gas into the liquid fuel nozzle 20 to flush the liquid fuel 200 into the combustion chamber 3, clogging of the flow path of the liquid fuel nozzle due to caulking can be prevented.

When the combustion method is switched from mixed fuel-only operation (gas-only firing) to start-up liquid fuel operation (oil-only firing) and the gas turbine is stopped, caulking also occurs due to the high temperature inside the combustor. Therefore, it is also necessary to purge the liquid fuel from the liquid fuel nozzle 20 even after the gas turbine is stopped.

9 is an enlarged view showing the vicinity of the starting fuel nozzle, which includes: a purge system for supplying nitrogen gas 400 to the starting fuel supply system; and a branched mixed fuel supply system for supplying gaseous fuel to the starting fuel supply system 201 is part of the gaseous fuel cleaning system 201a. In the respective systems, the shutoff valve 401 of the nitrogen purge system and the shutoff valve 201b of the gas fuel purge system are respectively provided.

Next, the fuel switching and the purge operation of starting fuel will be described. After starting with liquid fuel 200 and reaching the load condition for switching to gaseous fuel 201, reduce the flow rate of liquid fuel 200 supplied to the liquid fuel nozzle 20 of the burner while increasing the flow rate of gaseous fuel 201 to perform fuel switching operate. When a predetermined amount of gaseous fuel 201 is supplied and the flow rate of liquid fuel 200 becomes zero, fuel switching ends. At this time, if the liquid fuel remains in the liquid fuel nozzle 20 , caulking occurs in the liquid fuel nozzle 20 due to heat from the flame. Therefore, by opening the shutoff valve 401 of the nitrogen gas 400 and supplying the nitrogen gas 400 into the liquid fuel nozzle 20, the stagnant liquid fuel 200 can be flushed into the combustion chamber 3, and the occurrence of caulking can be suppressed. The purging system is aimed at purging liquid fuel. In addition, by continuing to supply nitrogen gas 400 into the combustion chamber after the cleaning is completed, since the flame temperature near the swirler end face is lowered, it is possible to reduce the swirler end face of the mixed fuel-only combustion operation (gas-only combustion operation). The effect of metal temperature.

In addition, the gaseous fuel 201 supplied to the start-up fuel supply system by branching the mixed fuel supply system is supplied to the liquid fuel nozzle 20 to obtain the same effect when cleaning the liquid fuel. Also, by flushing the liquid fuel 200 remaining in the liquid fuel nozzle into the combustion chamber and continuing to supply it to the combustion chamber after cleaning, the fuel concentration near the end surface of the swirler can be increased and a fuel rich area can be formed. Therefore, the flame temperature at the end face of the swirler can be lowered, thereby reducing the metal temperature at the end face of the swirler.

In these purge systems, the method of supplying nitrogen gas 400 from the liquid fuel nozzle 20 provided in the starting fuel nozzle 15 or continuing to supply the gaseous fuel 201 during the mixed fuel only combustion operation (gas only combustion) can also be used in the same way as in The method for cooling the end face of the cyclone in one embodiment is a combination of these two. With the above method, even if a fuel containing hydrogen or carbon monoxide or the like is combusted, the end face of the swirler can be effectively cooled.

Furthermore, as shown in FIG. 2 , the end face of the swirler is provided with a spray outlet 21 a for spraying air, a cooling hole 53 for ejecting gaseous fuel 201 into the combustion chamber, and an air swirler 17 for supplying compressed air to the combustion chamber. Tract 17a. In addition, the discharge port of the gaseous fuel or spray air injected into the combustion chamber from the mixed fuel nozzle 16 or the spray air nozzle 21 corresponds to a nozzle end surface.

As described above, in the first to third embodiments, methods for reducing the flame temperature in the vicinity of the swirler, which is the end near the starting fuel nozzle 15 and the mixed fuel nozzle 16 facing the combustion chamber, have been described. As shown in FIG. 8 , when the spray air 103 is supplied after shifting to the mixed-fuel combustion operation, the temperature of the metal at the end surface of the swirler may rise and exceed the melting point of the material forming the swirler. For example, the melting point of SUS steel is 650°C. When the melting point is exceeded, the air swirler 17 loses its function due to the burning of the swirler by the flame, or the outlet 16a of the mixed fuel nozzle 16 is blocked, which may cause the burner to fail to maintain the flame and reduce the burner's efficiency. reliability. Therefore, by having technical measures to lower the flame temperature near the swirler facing the combustion chamber below the melting point of the swirler component, it is possible to control the burning loss of the swirler component and improve the reliability of the burner.

Also, the first to third embodiments are useful when retrofitting an existing burner. For example, even when the existing burner uses LNG (liquefied natural gas), light oil, or type A heavy oil, it is possible to adapt to the change of the fuel type by simple modification.

Specifically, the first and second embodiments are also useful when retrofitting an existing burner. For example, in the case of a burner equipped with a starting fuel nozzle 15 and a mixed fuel nozzle 16, if it is a burner that uses liquid fuel for the starting combustion nozzle 15, it can be considered that it also has a burner for atomizing the liquid fuel. spray air supply system. Therefore, the temperature of the metal near the swirler can be lowered only by modifying the spray air supply system on the upstream side of the spray air nozzle 21 to supply the inert medium.

Furthermore, by replacing it with a member having cooling holes 53 on the nozzle end surface (swirler end surface) 18 of the combustion chamber facing the burner 13, the metal temperature near the swirler can be further reduced. However, since replacement of this part requires removal of the burner 13 from the burner, it is better to modify it to supply an inert medium to the spray air system, as the modification can be done more easily without dismantling the burner.

Furthermore, the third embodiment is also useful when retrofitting an existing burner. In order to clean the liquid fuel 200 stagnated inside the liquid fuel nozzle 20, the same effect as that of the third embodiment can be obtained only by adding a cleaning system for supplying nitrogen gas 400 to the starting fuel supply system. However, in order to supply the nitrogen gas 400, auxiliary equipment is required and the equipment is enlarged. Therefore, by branching the mixed fuel supply system and adding a gas fuel cleaning system 201a for supplying a part of the gas fuel 201 to the start-up fuel supply system, in order to supply the mixed fuel to the burner, the existing installation in the mixing system can be shared. The discharge pressure of the air compressor of the fuel supply system can be reduced, so the equipment can be miniaturized.

Claims (14)

1. pulverizing jet in the combustion chamber of gas turbine burner, is characterized in that possessing any one the hybrid fuel jet that comprises hydrogen or carbon monoxide at least:

The start-of-injection starting fuel nozzle of fuel in above-mentioned combustion chamber;

Be arranged at this starting fuel nozzle around, spray the hybrid fuel nozzle of above-mentioned fuel combination;

Be arranged at the end of above-mentioned combustion chamber one side of this hybrid fuel nozzle, and have when keeping flame to be ejected into many runners of above-mentioned combustion chamber from the compressed-air actuated part of air compressor machine, the squit hole of above-mentioned hybrid fuel nozzle is configured in the air gyroscope on the interior perimembranous of above-mentioned runner; And

Be arranged at the nozzle face in the face of above-mentioned combustion chamber, and the part of the fuel combination that will spray from above-mentioned hybrid fuel nozzle in order to reduce near the flame temperature the nozzle face is ejected into the cooling hole of above-mentioned combustion chamber.

2. pulverizing jet according to claim 1 is characterized in that,

Above-mentioned starting fuel nozzle comprises being arranged at and sprays the liquid fuel nozzle that gas turbine works the liquid fuel of employing; And be arranged at this liquid fuel nozzle around, spray the spray air nozzle be used to make the micronized spray air of liquid fuel.

3. pulverizing jet according to claim 1 is characterized in that,

Above-mentioned starting fuel nozzle arrangement is in the centre of the radial direction of the main chamber's lining that forms above-mentioned combustion chamber.

4. pulverizing jet according to claim 1 is characterized in that,

Also possesses inert media feed system from inert media to above-mentioned starting fuel nozzle that supply with; When the special burning of carrying out above-mentioned fuel combination is moved, will supply with above-mentioned starting fuel nozzle from the inert media of above-mentioned inert media feed system; And utilize above-mentioned starting fuel nozzle that inert media is ejected near the nozzle face.

5. pulverizing jet according to claim 1 is characterized in that,

Above-mentioned fuel combination is the gasification gas of coke-stove gas, blast furnace gas, coal gas of converter, coal, heavy oil etc.

6. gas turbine burner comprises in any one the gas turbine burner of fuel combination of hydrogen or carbon monoxide at least in burning, it is characterized in that possessing:

Urceolus as pressure vessel;

Be arranged at inner periphery one side of this urceolus, and main chamber's lining of the combustion chamber of portion's formation within it;

The pulverizing jet that is used for the above-mentioned combustion chamber formation flame in this main chamber's lining; And

This pulverizing jet is directed to the tail pipe of turbine by the burning gases that form flame and take place; And above-mentioned pulverizing jet possesses:

The start-of-injection starting fuel nozzle of fuel in above-mentioned combustion chamber;

Be arranged at this starting fuel nozzle around, spray the hybrid fuel nozzle of above-mentioned fuel combination;

Be arranged at the end of above-mentioned combustion chamber one side of this hybrid fuel nozzle, and have when keeping flame to be ejected into many runners of above-mentioned combustion chamber from the compressed-air actuated part of air compressor machine, the squit hole of above-mentioned hybrid fuel nozzle is configured in the air gyroscope on the inner circumference portion of above-mentioned runner; And

Be arranged at the nozzle face in the face of above-mentioned combustion chamber, and the part of the fuel combination that will spray from above-mentioned hybrid fuel nozzle in order to reduce near the flame temperature the nozzle face is ejected into the cooling hole of above-mentioned combustion chamber.

7. the cooling means of a pulverizing jet in will comprising any one the cooling means of pulverizing jet of the diffusion combustion mode of hybrid fuel jet in the combustion chamber of gas turbine burner of hydrogen or carbon monoxide at least, is characterized in that:

By facing the cooling hole that a part that sprays above-mentioned fuel combination is set on the nozzle face of above-mentioned combustion chamber, and cool off hole by this above-mentioned hybrid fuel jet is arrived above-mentioned combustion chamber, near thereby the flame temperature the reduction nozzle face, thus, the rising of the metal temperature of control nozzle face.

8. pulverizing jet in will comprising any one the pulverizing jet of hybrid fuel jet in the combustion chamber of gas turbine burner of hydrogen or carbon monoxide at least, is characterized in that possessing:

By gas turbine is risen the liquid fuel of employing be ejected into the liquid fuel nozzle of above-mentioned combustion chamber and be arranged at this liquid fuel nozzle around, and spray the starting fuel nozzle that the spray air nozzle be used to make the micronized spray air of liquid fuel constitutes;

Be arranged at this starting fuel nozzle around, and spray the hybrid fuel nozzle of above-mentioned fuel combination;

Be arranged at the end of above-mentioned combustion chamber one side of this hybrid fuel nozzle, and for keeping flame will be ejected into the air gyroscope of above-mentioned combustion chamber from the compressed-air actuated part of air compressor machine; And

Supply with the inert media feed system of inert media to above-mentioned starting fuel nozzle; And,

When the special burning operation of carrying out above-mentioned fuel combination, will supply with above-mentioned starting fuel nozzle from the inert media of above-mentioned inert media feed system, and utilize above-mentioned starting fuel nozzle that inert media is ejected near the nozzle face.

9. gas turbine burner comprises in any one the gas turbine burner of fuel combination of hydrogen or carbon monoxide at least in burning, it is characterized in that possessing:

Urceolus as pressure vessel;

Be arranged at inner periphery one side of this urceolus, and main chamber's lining of the combustion chamber of portion's formation within it;

The pulverizing jet that is used for the above-mentioned combustion chamber formation flame in this main chamber's lining; And

This pulverizing jet is directed to the tail pipe of turbine by the burning gases that form flame and take place; And above-mentioned pulverizing jet possesses:

By gas turbine is risen the liquid fuel of employing be ejected into the liquid fuel nozzle of above-mentioned combustion chamber and be arranged at this liquid fuel nozzle around, and spray the starting fuel nozzle that the spray air nozzle be used to make the micronized spray air of liquid fuel constitutes;

Be arranged at this starting fuel nozzle around, spray the hybrid fuel nozzle of above-mentioned fuel combination;

Be arranged at the end of above-mentioned combustion chamber one side of this hybrid fuel nozzle, and have for keeping flame will be ejected into the air gyroscope of above-mentioned combustion chamber from the compressed-air actuated part of air compressor machine; And

Supply with the inert media feed system of inert media to above-mentioned starting fuel nozzle; And,

When the special burning operation of carrying out above-mentioned fuel combination, will supply with above-mentioned starting fuel nozzle from the inert media of above-mentioned inert media feed system, and utilize above-mentioned starting fuel nozzle that inert media is ejected near the nozzle face.

10. the cooling means of a pulverizing jet in will comprising any one the cooling means of pulverizing jet of the diffusion combustion mode of hybrid fuel jet in the combustion chamber of gas turbine burner of hydrogen or carbon monoxide at least, is characterized in that:

The hybrid fuel nozzle that sprays above-mentioned fuel combination is being set to above-mentioned combustion chamber start-of-injection around with the starting fuel nozzle of fuel;

By when the special burning of carrying out above-mentioned fuel combination is moved, to supply with above-mentioned starting fuel nozzle from the inert media of above-mentioned inert media feed system, and utilize above-mentioned starting fuel nozzle that inert media is ejected near the nozzle face, near thereby the flame temperature the reduction nozzle face, thus, the rising of the metal temperature of control nozzle face.

11. a pulverizing jet in will comprising any one the pulverizing jet of hybrid fuel jet in the combustion chamber of gas turbine burner of hydrogen or carbon monoxide at least, is characterized in that possessing:

Starting fuel is ejected into starting fuel nozzle in the above-mentioned combustion chamber;

Be arranged at this starting fuel nozzle around, spray the hybrid fuel nozzle of above-mentioned fuel combination;

Be arranged at the end of above-mentioned combustion chamber one side of this hybrid fuel nozzle, and have when keeping flame to be ejected into many runners of above-mentioned combustion chamber from the compressed-air actuated part of air compressor machine, the squit hole of above-mentioned hybrid fuel nozzle is configured in the air gyroscope on the inner circumference portion of above-mentioned runner; And

Mechanism from above-mentioned starting fuel nozzle cleaning fuel.

12. pulverizing jet according to claim 11 is characterized in that, the mechanism of cleaning above-mentioned fuel possesses the system that a part of supplying with the fuel combination of above-mentioned hybrid fuel nozzle is supplied with above-mentioned starting fuel nozzle.

13. a pulverizing jet in will comprising any one the pulverizing jet of hybrid fuel jet in the combustion chamber of gas turbine burner of hydrogen or carbon monoxide at least, is characterized in that having the cyclone in the face of above-mentioned combustion chamber, above-mentioned combustion chamber possesses:

Starting fuel is ejected into the starting fuel nozzle of above-mentioned combustion chamber;

Be arranged at this starting fuel nozzle around, and spray the hybrid fuel nozzle of above-mentioned fuel combination;

Be arranged at the end of above-mentioned combustion chamber one side of this hybrid fuel nozzle, and have when keeping flame will be ejected into many runners in the above-mentioned combustion chamber from the compressed-air actuated part of air compressor machine, the squit hole of above-mentioned hybrid fuel nozzle is configured in the air gyroscope of the inner circumference portion of above-mentioned runner;

Also possess and make the following mechanism of fusing point that is reduced to the cyclone parts in the face of near the flame temperature the cyclone of above-mentioned combustion chamber.

14. the remodeling method of a pulverizing jet in will comprising any one the remodeling method of the pulverizing jet of hybrid fuel jet in the combustion chamber of gas turbine burner of hydrogen or carbon monoxide at least, is characterized in that pulverizing jet possesses:

Be ejected into the liquid fuel nozzle in the above-mentioned combustion chamber and be arranged at around this liquid fuel nozzle by gas turbine being worked the liquid fuel of employing, and spray the starting fuel nozzle that the spray air nozzle that is used to make the micronized spray air of liquid fuel constitutes;

Be arranged at this starting fuel nozzle around, spray the hybrid fuel nozzle of above-mentioned fuel combination; And

Be arranged at the end of above-mentioned combustion chamber one side of this hybrid fuel nozzle, and for keeping flame will be ejected into many runners of above-mentioned combustion chamber from the compressed-air actuated part of air compressor machine;

On above-mentioned pulverizing jet, also set up the mechanism that supplies with inert media to above-mentioned spray air nozzle.

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