Burner modification method, and burner

Abstract

This burner modification method includes: performing a first step (step S110) for removing a sealing plate provided at the rear end of a first fuel nozzle; after the first step, performing a second step (step S120) for inserting a second fuel nozzle into the first fuel nozzle from the rear end of the first fuel nozzle; and, after the second step, performing a third step (step S130) for fixing the second fuel nozzle to the first fuel nozzle.

Description

Method for modifying a burner and burner

[0001] The present disclosure relates to a method for modifying a burner and a burner. This application claims the benefit of priority based on Japanese Patent Application No. 2025-015180 filed on January 31, 2025, the content of which is incorporated herein by reference.

[0002] In recent years, in order to prevent global warming, reduction of carbon dioxide (CO ２ 2) emissions has been demanded. For this reason, in addition to fossil fuels, technologies for burning carbon-neutral fuels such as ammonia, hydrogen, and biomass have been studied. For example, Patent Document 1 discloses a boiler that co-fires coal and ammonia.

[0003] Japanese Patent Application Laid-Open No. 2023-95048

[0004] As described above, by burning carbon-neutral fuels, carbon dioxide emissions can be reduced. On the other hand, installing a new burner is a factor that increases costs. Therefore, there is a need to develop a technology for changing fuels using an existing burner.

[0005] In view of such problems, an object of the present disclosure is to provide a method for modifying a burner and a burner that enables fuel change using an existing burner.

[0006] To solve the above problems, a method for modifying a burner according to an aspect of the present disclosure includes performing a first step of removing a sealing plate provided at the rear end of a first fuel nozzle, and after the first step, performing a second step of inserting a second fuel nozzle into the first fuel nozzle from the rear end of the first fuel nozzle, and after the second step, performing a third step of fixing the second fuel nozzle to the first fuel nozzle.

[0007] The first fuel nozzle has a first nozzle and a second nozzle provided inside the first nozzle, and in the second step, the second fuel nozzle may be inserted into the second nozzle.

[0008] The sealing plate is fixed to the first fuel nozzle by inserting a first bolt through a bolt hole provided in the first fuel nozzle. In the first step, the sealing plate is removed by removing the first bolt from the bolt hole. In the third step, the second fuel nozzle may be fixed to the first fuel nozzle by inserting a second bolt through the bolt hole.

[0009] In the first step, in addition to the sealing plate, the starting fuel nozzle provided in the first fuel nozzle is removed; in the second step, in addition to the second fuel nozzle, the starting fuel nozzle is inserted into the first fuel nozzle; and in the third step, in addition to the second fuel nozzle, the starting fuel nozzle may be fixed to the first fuel nozzle.

[0010] The burner is equipped with a moving device for moving the ignition fuel nozzle, and the moving device may be shared before the ignition fuel nozzle is removed from the first fuel nozzle in the first step and after the ignition fuel nozzle is fixed to the first fuel nozzle in the third step.

[0011] The first fuel nozzle may supply coal, and the second fuel nozzle may supply ammonia.

[0012] To solve the above problems, a burner according to one aspect of the present disclosure comprises a first fuel nozzle and a second fuel nozzle that is inserted into the first fuel nozzle with the sealing plate provided at the rear end of the first fuel nozzle removed and fixed to the first fuel nozzle.

[0013] According to this disclosure, it is possible to change the fuel using an existing burner.

[0014] Figure 1 is a schematic diagram showing a boiler according to an embodiment of the present disclosure. Figure 2 is a schematic diagram showing a burner before modification according to the same embodiment. Figure 3 is a flowchart showing the processing flow of the burner modification method according to the same embodiment. Figure 4 is a first diagram showing the first step according to the same embodiment. Figure 5 is a second diagram showing the first step according to the same embodiment. Figure 6 is a first diagram showing the second step according to the same embodiment. Figure 7 is a second diagram showing the second step according to the same embodiment. Figure 8 is a first diagram showing the third step according to the same embodiment. Figure 9 is a second diagram showing the third step according to the same embodiment.

[0015] Embodiments of this disclosure will be described in detail below with reference to the attached drawings. The dimensions, materials, and other specific numerical values ​​shown in the embodiments are merely examples for the purpose of facilitating understanding and do not limit this disclosure unless otherwise specified. In this specification and in the drawings, elements having substantially the same function or configuration are denoted by the same reference numerals to avoid redundant explanations. Elements not directly related to this disclosure are omitted from the illustrations.

[0016] [1. Overview of the Burner Before Modification] First, an overview of the burner 10 before modification according to the embodiment of this disclosure will be described with reference to Figures 1 and 2. Figure 1 is a schematic diagram showing the boiler 1 according to this embodiment. Figure 2 is a schematic diagram showing the burner 10 before modification according to this embodiment.

[0017] As shown in Figure 1, the boiler 1 according to this embodiment comprises a furnace 2, a flue 3, and a burner 10.

[0018] The furnace 2 is a furnace that generates combustion heat by burning fuel. The furnace 2 has a cylindrical shape, such as a rectangular cylinder, that extends vertically. High-temperature combustion gases are generated in the furnace 2 when the fuel burns. An outlet 2a is provided at the bottom of the furnace 2 to discharge the ash generated by the combustion of the fuel to the outside.

[0019] Flue 3 is a passage that guides the combustion gases generated in the furnace 2 to the outside as exhaust gas. Flue 3 is connected to the top of the furnace 2.

[0020] Boiler 1 is equipped with a superheater (not shown) installed on top of the furnace 2, etc. In the superheater, heat exchange takes place between the combustion heat generated in the furnace 2 and water. This generates steam. Boiler 1 may also be equipped with various devices (not shown), such as a reheater, economizer, or air preheater.

[0021] The burner 10 is provided on the lower wall of the furnace 2. For example, the furnace 2 has multiple burners 10 spaced apart in the circumferential direction of the furnace 2. The multiple burners 10 may also be spaced apart in the vertical direction, which is the direction in which the furnace 2 extends. The burner 10 injects fuel into the furnace 2. When the fuel injected from the burner 10 burns, a flame F is formed in the furnace 2. The furnace 2 is also provided with an ignition device (not shown) that ignites the fuel injected from the burner 10.

[0022] As shown in Figure 2, the burner 10 before modification according to this embodiment is attached to the wall of the furnace 2. Specifically, the burner 10 is positioned to penetrate the wall of the furnace 2 and span from the outside to the inside of the furnace 2. The burner 10 injects a first fuel into the furnace 2 as fuel. The first fuel is, for example, coal (for example, pulverized coal). In other words, the burner 10 before modification is, for example, a coal-fired burner. In this embodiment, the burner 10 includes a first fuel nozzle 20, a sealing plate 30, an activation fuel nozzle 40, and a moving device 50. In the following, an example in which the burner 10 is provided with an activation fuel nozzle 40 and a moving device 50 will be mainly described. However, as will be described later, the burner 10 does not necessarily have to be provided with an activation fuel nozzle 40 and a moving device 50.

[0023] The first fuel nozzle 20 is a nozzle that supplies coal as the first fuel to the furnace 2. In this embodiment, the first fuel nozzle 20 has, for example, a first nozzle 22 and a second nozzle 24.

[0024] The first nozzle 22 is a nozzle for supplying pulverized coal. The second nozzle 24 is a nozzle for narrowing the diameter of the injection port 22b of the first nozzle 22, which will be described later. The first nozzle 22 and the second nozzle 24 have a cylindrical shape. The second nozzle 24 is provided inside the first nozzle 22. That is, the second nozzle 24 is inserted into the interior of the first nozzle 22. The first nozzle 22 and the second nozzle 24 are provided, for example, coaxially. That is, the first nozzle 22 is arranged coaxially with the second nozzle 24, surrounding the outer circumferential surface of the second nozzle 24. The first nozzle 22 and the second nozzle 24 form a double cylindrical structure. The central axes of the first nozzle 22 and the second nozzle 24 intersect, for example, the wall of the furnace 2. Specifically, the central axes of the first nozzle 22 and the second nozzle 24 are approximately perpendicular to the wall of the furnace 2.

[0025] Hereinafter, the side of the burner 10 facing the furnace 2 (right side in Figure 2) will be referred to as the front end, and the side of the burner 10 opposite to the furnace 2 (left side in Figure 2) will be referred to as the rear end. The radial direction, axial direction, and circumferential direction of the burner 10 will also be simply referred to as the radial direction, axial direction, and circumferential direction, respectively.

[0026] The first nozzle 22 includes a body 22a, an injection port 22b, and a supply port 22c. The body 22a has a cylindrical shape. The body 22a extends along the central axis of the burner 10. The body 22a has a shape that tapers towards the tip, for example. The injection port 22b is an opening provided at the tip of the body 22a. The injection port 22b is an annular opening between the tip of the body 22a and the tip of the body 24a of the second nozzle 24, which will be described later. The injection port 22b faces the internal space of the furnace 2. In other words, the injection port 22b faces the internal space of the furnace 2. The supply port 22c is provided at the rear of the body 22a. The supply port 22c is connected to a pulverized coal supply source (not shown).

[0027] The pulverized coal, along with air for transporting the pulverized coal, is supplied from the pulverized coal supply source to the main body 22a via the supply port 22c. The pulverized coal supplied to the main body 22a flows along with the air in the space between the inner circumference of the main body 22a and the outer circumference of the second nozzle 24a. The pulverized coal that has passed through the main body 22a is injected from the injection port 22b towards the internal space of the furnace 2. In this way, the first nozzle 22 is provided facing the internal space of the furnace 2.

[0028] The second nozzle 24 includes a body 24a, a nozzle 24b, and an opening 24c. The body 24a has a cylindrical shape. The body 24a is provided coaxially with the body 22a of the first nozzle 22. The body 24a has a shape that tapers towards the tip, for example. The nozzle 24b is an opening provided at the tip of the body 24a. The nozzle 24b faces the internal space of the furnace 2. In other words, the nozzle 24b faces the internal space of the furnace 2. The opening 24c is provided at the rear end of the body 24a. The opening 24c is sealed by a sealing plate 30, which will be described later.

[0029] The sealing plate 30, which will be described later, is provided with an air supply port 30b. Air is supplied from an air supply source into the main body 24a via the air supply port 30b. The air that has passed through the main body 24a is supplied from the injection port 24b toward the internal space of the furnace 2. In this way, the second nozzle 24 is provided toward the internal space of the furnace 2. The air supplied into the main body 24a via the air supply port 30b suppresses the backflow of unburned fuel generated in the furnace 2 and ash generated by the combustion of the fuel into the main body 24a.

[0030] The sealing plate 30 is provided at the rear end of the second nozzle 24. As described above, the sealing plate 30 seals the opening 24c of the second nozzle 24. For example, the sealing plate 30 has a disc shape. More specifically, a plurality of bolt holes 24d are provided at the rear end of the body 24a of the second nozzle 24. For example, the plurality of bolt holes 24d are arranged at intervals in the circumferential direction of the burner 10. For example, the second nozzle 24 is provided with an annular flange portion 24e extending radially outward from the rear end of the body 24a. Each bolt hole 24d is located in the flange portion 24e. The sealing plate 30 is also provided with a plurality of bolt holes 30a. For example, the plurality of bolt holes 30a are arranged at intervals in the circumferential direction of the sealing plate 30. For example, each bolt hole 30a is located along the outer edge of the sealing plate 30. For example, each bolt hole 30a of the sealing plate 30 is radially aligned with each bolt hole 24d of the second nozzle 24. Also, the circumferential spacing of the multiple bolt holes 30a of the sealing plate 30 is equal to, for example, the circumferential spacing of the multiple bolt holes 24d of the second nozzle 24. The sealing plate 30 is fixed to the second nozzle 24 by inserting a first bolt B1 through the bolt hole 24d of the second nozzle 24 and the bolt hole 30a of the sealing plate 30, and screwing a first nut N1 onto the first bolt B1.

[0031] As described above, the sealing plate 30 is provided with an air supply port 30b. For example, the air supply port 30b is positioned radially outward with respect to the central axis of the sealing plate 30. The sealing plate 30 is also provided with a through hole 30c. The starting fuel nozzle 40, which will be described later, is inserted through the through hole 30c. For example, the through hole 30c is positioned coaxially with the central axis of the sealing plate 30.

[0032] The starting fuel nozzle 40 is a nozzle that supplies fuel for starting. The starting fuel is, for example, light oil. The starting fuel nozzle 40 is used to preheat the furnace 2 when starting the furnace 2. The starting fuel nozzle 40 has a cylindrical shape. The starting fuel nozzle 40 is installed inside the second nozzle 24. That is, the starting fuel nozzle 40 is inserted into the interior of the second nozzle 24. The starting fuel nozzle 40 is installed, for example, coaxially with the first nozzle 22 and the second nozzle 24. The first nozzle 22, the second nozzle 24, and the starting fuel nozzle 40 form a triple cylindrical structure. The central axis of the starting fuel nozzle 40 intersects, for example, the wall of the furnace 2, similar to the first nozzle 22 and the second nozzle 24. Specifically, the central axis of the starting fuel nozzle 40 is approximately perpendicular to the wall of the furnace 2.

[0033] The starting fuel nozzle 40 includes a main body 40a, an injection port 40b, and a supply port 40c. The main body 40a has a cylindrical shape. The main body 40a extends along the central axis of the burner 10. The inner diameter of the main body 40a is, for example, substantially constant regardless of the axial position. The main body 40a passes through the through hole 30c of the sealing plate 30. The space between the inner circumference of the through hole 30c of the sealing plate 30 and the outer circumference of the main body 40a is sealed. The injection port 40b is an opening provided at the tip of the main body 40a. The injection port 40b faces the internal space of the furnace 2. In other words, the injection port 40b faces the internal space of the furnace 2. The supply port 40c is provided at the rear of the main body 40a. The supply port 40c is connected to a starting fuel supply source (not shown).

[0034] The starting fuel is supplied from the starting fuel supply source to the main body 40a via the supply port 40c. The starting fuel supplied to the main body 40a is injected from the injection port 40b towards the internal space of the furnace 2. In this way, the starting fuel nozzle 40 is provided facing the internal space of the furnace 2.

[0035] The moving device 50 moves the starting fuel nozzle 40 in the axial direction. For example, when starting the furnace 2, the moving device 50 causes the starting fuel nozzle 40 to protrude into the internal space of the furnace 2. Also, when igniting the burner 10, the moving device 50 retracts the starting fuel nozzle 40 from the internal space of the furnace 2. The moving device 50 includes, for example, an air cylinder.

[0036] [2. Method for Modifying the Burner] Next, a method for modifying the burner 10 according to this embodiment will be described with reference to Figures 3 to 9. Figure 3 is a flowchart showing the processing flow of the method for modifying the burner 10 according to this embodiment. Figure 4 is a first diagram showing the first step according to this embodiment. Figure 5 is a second diagram showing the first step according to this embodiment. Figure 6 is a first diagram showing the second step according to this embodiment. Figure 7 is a second diagram showing the second step according to this embodiment. Figure 8 is a first diagram showing the third step according to this embodiment. Figure 9 is a second diagram showing the third step according to this embodiment.

[0037] In step S110, a first step is performed in which the sealing plate 30 provided at the rear end of the first fuel nozzle 20 is removed. As shown in Figure 4, in the first step according to this embodiment, first, the starting fuel nozzle 40 provided inside the first fuel nozzle 20 is removed. Specifically, the starting fuel nozzle 40 is pulled out through the through hole 30c of the sealing plate 30.

[0038] Then, as shown in Figure 5, the first nut N1 is removed from the first bolt B1, and the first bolt B1 is removed from the bolt hole 30a of the sealing plate 30 and the bolt hole 24d of the second nozzle 24, thereby removing the sealing plate 30.

[0039] Next, following the first step, in step S120, a second step is performed in which the second fuel nozzle 70 is inserted into the first fuel nozzle 20 from the rear end of the first fuel nozzle 20. As shown in Figure 6, in the second step according to this embodiment, the second fuel nozzle 70 is inserted into the second nozzle 24 of the first fuel nozzle 20. The second fuel nozzle 70 is a nozzle that supplies the second fuel. The second fuel is a different fuel from the first fuel. The second fuel is, for example, ammonia.

[0040] In this embodiment, the second fuel nozzle 70 includes a body 70a, an injection port 70b, and a supply port 70c. The body 70a has a bottomed cylindrical shape. The body 70a extends along the central axis of the first fuel nozzle 20. The inner and outer diameters of the body 70a are substantially constant regardless of, for example, the axial position. The injection port 70b is an opening provided at the tip of the body 70a. The injection port 70b faces the internal space of the furnace 2. That is, the injection port 70b faces the internal space of the furnace 2. The supply port 70c is provided at the rear of the body 70a.

[0041] Furthermore, a through-hole 70e is provided in the bottom 70d of the rear end of the main body 70a of the second fuel nozzle 70, through which the starting fuel nozzle 40 can be inserted. In other words, the through-hole 70e penetrates the bottom 70d of the main body 70a. For example, the through-hole 70e is positioned coaxially with the central axis of the main body 70a.

[0042] Furthermore, the rear of the second fuel nozzle 70 is provided with an annular flange portion 70f extending radially outward from the outer circumferential surface of the main body 70a. Multiple bolt holes 70g are provided in this flange portion 70f, corresponding to the multiple bolt holes 24d of the second nozzle 24 of the first fuel nozzle 20. For example, each bolt hole 70g of the second fuel nozzle 70 coincides radially with each bolt hole 24d of the second nozzle 24. Also, the circumferential spacing of the multiple bolt holes 70g of the second fuel nozzle 70 is equal to, for example, the circumferential spacing of the multiple bolt holes 24d of the second nozzle 24.

[0043] Furthermore, as shown in Figure 7, in the second step according to this embodiment, in addition to the second fuel nozzle 70, an ignition fuel nozzle 40 is inserted into the first fuel nozzle 20. Specifically, the ignition fuel nozzle 40 is inserted through the through hole 70e of the second fuel nozzle 70, and the ignition fuel nozzle 40 is inserted into the second fuel nozzle 70. The space between the inner circumference of the through hole 70e of the second fuel nozzle 70 and the outer circumference of the main body 40a of the ignition fuel nozzle 40 is sealed.

[0044] Incidentally, in the second step, as described above, first, the second fuel nozzle 70 may be inserted into the first fuel nozzle 20, and then, the starting fuel nozzle 40 may be inserted into the second fuel nozzle 70. However, in the second step, first, the starting fuel nozzle 40 may be inserted into the second fuel nozzle 70, and then, the second fuel nozzle 70 into which the starting fuel nozzle 40 is inserted may be inserted into the first fuel nozzle 20.

[0045] Subsequently, after the second step, in step S130, a third step of fixing the second fuel nozzle 70 to the first fuel nozzle 20 is performed. As shown in FIG. 8, in the third step according to the present embodiment, the second fuel nozzle 70 is fixed to the first fuel nozzle 20 by inserting the second bolt B2 through the bolt hole 24d of the second nozzle 24 and the bolt hole 70g of the second fuel nozzle 70 and screwing the second nut N2 onto the second bolt B2. The second bolt B2 may be the same bolt as the first bolt B1 or a different bolt. Similarly, the second nut N2 may be the same nut as the first nut N1 or a different nut.

[0046] Also, as described above, in the second step according to the present embodiment, the starting fuel nozzle 40 is fixed to the second fuel nozzle 70. Therefore, in the third step, when the second fuel nozzle 70 is fixed to the first fuel nozzle 20, in addition to the second fuel nozzle 70 being fixed to the first fuel nozzle 20, the starting fuel nozzle 40 is also fixed to the first fuel nozzle 20.

[0047] Further, the moving device 50 may be shared before the starting fuel nozzle 40 is removed from the first fuel nozzle 20 in the first step and after the starting fuel nozzle 40 is fixed to the first fuel nozzle 20 in the third step.

[0048] An ammonia supply source (not shown) is connected to the supply port 70c of the second fuel nozzle 70. The ammonia supply source stores, for example, liquid ammonia. Liquid or gaseous ammonia is supplied from the ammonia supply source to the body 70a of the second fuel nozzle 70 via the supply port 70c. The ammonia that has passed through the body 70a is injected from the injection port 70b towards the internal space of the furnace 2. In this way, the second fuel nozzle 70 is provided facing the internal space of the furnace 2.

[0049] Furthermore, when the second fuel nozzle 70 injects gaseous ammonia, the ammonia stored in the ammonia supply source is vaporized by the vaporizer. The vaporized ammonia is then supplied to the second fuel nozzle 70.

[0050] Thus, the burner 10 before modification is modified into a burner 100, as shown in Figure 9. The modified burner 100 comprises a first fuel nozzle 20 and a second fuel nozzle 70 which is inserted into the first fuel nozzle 20 with the sealing plate 30 provided at the rear end of the first fuel nozzle 20 removed and fixed to the first fuel nozzle 20.

[0051] [3. Summary] The method for modifying the burner 10 and the burner 100 according to this embodiment have been described above.

[0052] The method for modifying the burner 10 according to this embodiment includes: a first step (step S110) of removing the sealing plate 30 provided at the rear end of the first fuel nozzle 20; a second step (step S120) of inserting the second fuel nozzle 70 into the first fuel nozzle 20 from the rear end of the first fuel nozzle 20 after the first step; and a third step (step S130) of fixing the second fuel nozzle 70 to the first fuel nozzle 20 after the second step.

[0053] As a result, the method for modifying the burner 10 according to this embodiment allows the burner 10 that burns the first fuel to be modified into a burner 100 that can burn a second fuel in addition to the first fuel. Furthermore, the method for modifying the burner 10 according to this embodiment allows the second fuel nozzle 70 to be inserted into the first fuel nozzle 20 by a simple operation such as removing the sealing plate 30 and inserting the second fuel nozzle 70 into the first fuel nozzle 20 from the rear end of the first fuel nozzle 20. Therefore, the method for modifying the burner 10 according to this embodiment can utilize existing equipment as much as possible, thus suppressing cost increases. For example, there is no need to newly form a hole in the wall of the furnace 2 for inserting the second fuel nozzle 70, and the first fuel nozzle 20 can be used as is. Thus, the method for modifying the burner 10 according to this embodiment makes it possible to change the fuel using an existing burner.

[0054] The first fuel nozzle 20 has a first nozzle 22 and a second nozzle 24 provided inside the first nozzle 22, and in the second step, the second fuel nozzle 70 may be inserted into the second nozzle 24.

[0055] Thus, the first fuel nozzle 20 according to this embodiment has a first nozzle 22 and a second nozzle 24 provided inside the first nozzle 22. In the modification method of the burner 10 according to this embodiment, the second fuel nozzle 70 is inserted into the second nozzle 24, so the space inside the second nozzle 24 of the first fuel nozzle 20 can be used for the installation of the second fuel nozzle 70. Therefore, in the modification method of the burner 10 according to this embodiment, the space between the first nozzle 22 and the second nozzle 24 of the first fuel nozzle 20 can be used as a flow path for the first fuel, just as before the modification. Thus, in the modified burner 100 according to this embodiment, the co-firing of the first fuel and the second fuel can be appropriately achieved.

[0056] The sealing plate 30 is fixed to the first fuel nozzle 20 by inserting a first bolt B1 through a bolt hole 24d provided in the first fuel nozzle 20. In the first step, the sealing plate 30 is removed by removing the first bolt B1 from the bolt hole 24d. In the third step, the second fuel nozzle 70 may be fixed to the first fuel nozzle 20 by inserting a second bolt B2 through the bolt hole 24d.

[0057] As a result, the modification method for the burner 10 according to this embodiment allows the bolt holes 24d provided in the first fuel nozzle 20 for fixing the sealing plate 30 to be reused for fixing the second fuel nozzle 70. Therefore, the modification method for the burner 10 according to this embodiment allows the second fuel nozzle 70 to be fixed to the first fuel nozzle 20 without having to newly form holes in the first fuel nozzle 20 for fixing the second fuel nozzle 70. In other words, the modification method for the burner 10 according to this embodiment can utilize existing equipment as much as possible, thus suppressing cost increases.

[0058] In the first step, the ignition fuel nozzle 40 provided inside the first fuel nozzle 20 is removed in addition to the sealing plate 30; in the second step, the ignition fuel nozzle 40 is inserted into the first fuel nozzle 20 in addition to the second fuel nozzle 70; and in the third step, the ignition fuel nozzle 40 may be fixed to the first fuel nozzle 20 in addition to the second fuel nozzle 70.

[0059] As a result, the method for modifying the burner 10 according to this embodiment allows for the easy addition of a second fuel nozzle 70 to a burner 10 equipped with an ignition fuel nozzle 40. Furthermore, the method for modifying the burner 10 according to this embodiment allows for the reuse of the ignition fuel nozzle 40 in the modified burner 100. In other words, the method for modifying the burner 10 according to this embodiment can utilize existing equipment as much as possible, thereby suppressing cost increases.

[0060] The burner 10 is equipped with a moving device 50 for moving the ignition fuel nozzle 40, and the moving device 50 may be used in the same manner before the ignition fuel nozzle 40 is removed from the first fuel nozzle 20 in the first step and after the ignition fuel nozzle 40 is fixed to the first fuel nozzle 20 in the third step.

[0061] As a result, the method for modifying the burner 10 according to this embodiment allows the mobile device 50 to be reused in the modified burner 100. In other words, the method for modifying the burner 10 according to this embodiment can utilize existing equipment as much as possible, thus suppressing cost increases.

[0062] The first fuel nozzle 20 may supply coal, and the second fuel nozzle 70 may supply ammonia.

[0063] As a result, the method for modifying the burner 10 according to this embodiment can convert a coal-fired burner 10 into a burner 100 capable of co-firing coal and ammonia. Therefore, the method for modifying the burner 10 according to this embodiment can produce a burner 100 that can reduce carbon dioxide emissions.

[0064] Furthermore, the burner 100 according to this embodiment includes a first fuel nozzle 20 and a second fuel nozzle 70 which is inserted into the first fuel nozzle 20 with the sealing plate 30 provided at the rear end of the first fuel nozzle 20 removed and fixed to the first fuel nozzle 20.

[0065] The burner 100 according to this embodiment can achieve the same effects as those achieved by the modification method of the burner 10 described above.

[0066] While embodiments have been described above with reference to the attached drawings, it goes without saying that this disclosure is not limited to the embodiments described above. It will be obvious to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these will naturally also fall within the technical scope of this disclosure.

[0067] For example, in the above embodiment, the first fuel is coal and the second fuel is ammonia. However, the invention is not limited to this, and the first and second fuels may be different fuels. For example, the first and second fuels may be the same substance, but with different properties. For example, the first fuel may be a solid fuel, and the second fuel may be a liquid or gaseous fuel. Also, the first and second fuels may be different substances. For example, the first fuel may be a fossil fuel, and the second fuel may be a carbon-neutral fuel. Fossil fuels include, for example, coal, petroleum, and natural gas. Carbon-neutral fuels may include, for example, ammonia, hydrogen, biomass, and hydrocarbons produced from renewable energy (e.g., methane).

[0068] Furthermore, in the above embodiment, an example was given in which the burners 10 and 100 are equipped with a mobile device 50. However, the burners 10 and 100 do not necessarily have to be equipped with a mobile device 50.

[0069] Furthermore, in the second step of the above embodiment, the case in which the starting fuel nozzle 40 is inserted into the second fuel nozzle 70 was given as an example. However, in the second step, the starting fuel nozzle 40 does not need to be inserted into the second fuel nozzle 70 as long as it is inserted into the first fuel nozzle 20. For example, in the second step, the starting fuel nozzle 40 may be inserted between the inner circumference of the body 22a of the first nozzle 22 of the first fuel nozzle 20 and the outer circumference of the body 24a of the second nozzle 24. Alternatively, in the second step, the starting fuel nozzle 40 may be inserted between the inner circumference of the body 24a of the second nozzle 24 of the first fuel nozzle 20 and the outer circumference of the body 70a of the second fuel nozzle 70.

[0070] Furthermore, in the above embodiment, an example was given in which the burners 10 and 100 are equipped with an ignition fuel nozzle 40. However, the burners 10 and 100 do not have to be equipped with an ignition fuel nozzle 40. In this case, the sealing plate 30 does not have to be equipped with a through hole 30c. Also in this case, in the first step, the sealing plate 30 provided at the rear end of the first fuel nozzle 20 is removed. For example, in the first step, the sealing plate 30 is removed by removing the first bolt B1 from the bolt hole 30a of the sealing plate 30 and the bolt hole 24d of the second nozzle 24. Then, in the second step, the second fuel nozzle 70 is inserted into the first fuel nozzle 20 from the rear end of the first fuel nozzle 20. Also, in the third step, the second fuel nozzle 70 is fixed to the first fuel nozzle 20. For example, in the third step, the second fuel nozzle 70 is fixed to the first fuel nozzle 20 by inserting a second bolt B2 through the bolt hole 24d of the second nozzle 24 and the bolt hole 70g of the second fuel nozzle 70, and screwing a second nut N2 onto the second bolt B2.

[0071] Furthermore, in the above embodiment, the sealing plate 30 was given as an example in which it is fixed to the first fuel nozzle 20 by inserting a first bolt B1 through a bolt hole 24d provided in the first fuel nozzle 20. However, the method of fixing the sealing plate 30 is not limited as long as it is fixed to the rear end of the first fuel nozzle 20. For example, the sealing plate 30 may be fixed to the rear end of the first fuel nozzle 20 by screwing, clamping, etc. In this case, in the third step, the second fuel nozzle 70 may be fixed to the first fuel nozzle 20 by screwing or clamping. Alternatively, a dedicated bolt hole for fixing the second fuel nozzle 70 may be formed in the first fuel nozzle 20, and in the third step, the second fuel nozzle 70 may be fixed to the first fuel nozzle 20 by inserting a second bolt B2 through the bolt hole. Alternatively, a dedicated screw hole may be formed in the first fuel nozzle 20 for fixing the second fuel nozzle 70, and in the third step, the second fuel nozzle 70 may be fixed to the first fuel nozzle 20 by screwing a screw into the screw hole.

[0072] Furthermore, in the above embodiment, the first fuel nozzle 20 was given as an example in which it has a first nozzle 22 and a second nozzle 24. However, the first fuel nozzle 20 may consist only of the first nozzle 22. In this case, in the second step, the second fuel nozzle 70 is inserted into the first nozzle 22. That is, the second fuel nozzle 70 is positioned within the flow path of the first fuel.

[0073] Furthermore, in the above embodiment, the example given was that the burners 10 and 100 are installed in the boiler 1. However, the burners 10 and 100 may also be installed in furnaces other than the boiler 1, such as incinerators, blast furnaces, lime furnaces, industrial kilns, etc.

[0074] This disclosure can contribute, for example, to Sustainable Development Goal 7, "Ensure access to affordable, reliable, sustainable and modern energy," and Goal 13, "Take urgent action to combat climate change and its impacts."

[0075] B1: First bolt B2: Second bolt 10: Burner 100: Burner 20: First fuel nozzle 22: First nozzle 24: Second nozzle 24d: Bolt hole 30: Sealing plate 40: Starting fuel nozzle 50: Moving device 70: Second fuel nozzle

Claims

1. A method for modifying a burner, comprising:

1. Performing a first step of removing a sealing plate provided at the rear end of a first fuel nozzle; 2. Performing a second step of inserting a second fuel nozzle into the first fuel nozzle from the rear end of the first fuel nozzle after the first step; and 3. Performing a third step of fixing the second fuel nozzle to the first fuel nozzle after the second step.

2. The method for modifying a burner according to claim 1, wherein the first fuel nozzle has a first nozzle and a second nozzle provided inside the first nozzle, and in the second step, the second fuel nozzle is inserted into the second nozzle.

3. The method for modifying a burner according to claim 1 or 2, wherein the sealing plate is fixed to the first fuel nozzle by inserting a first bolt through a bolt hole provided in the first fuel nozzle, the sealing plate is removed in the first step by removing the first bolt from the bolt hole, and the second fuel nozzle is fixed to the first fuel nozzle in the third step by inserting a second bolt through the bolt hole.

4. A method for modifying a burner according to claim 1 or 2, wherein in the first step, in addition to the sealing plate, the starting fuel nozzle provided in the first fuel nozzle is removed; in the second step, in addition to the second fuel nozzle, the starting fuel nozzle is inserted into the first fuel nozzle; and in the third step, in addition to the second fuel nozzle, the starting fuel nozzle is fixed to the first fuel nozzle.

5. The method for modifying a burner according to claim 4, wherein the burner is equipped with a moving device for moving the starting fuel nozzle, and the moving device is used before the starting fuel nozzle is removed from the first fuel nozzle in the first step and after the starting fuel nozzle is fixed to the first fuel nozzle in the third step.

6. The method for modifying a burner according to claim 1 or 2, wherein the first fuel nozzle supplies coal and the second fuel nozzle supplies ammonia.

7. A burner comprising: a first fuel nozzle; and a second fuel nozzle inserted into the first fuel nozzle with the sealing plate provided at the rear end of the first fuel nozzle removed and fixed to the first fuel nozzle.

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