Combustion facility, power generation facility, and method of operating combustion facility

Abstract

To suppress a generation amount of nitrogen oxide (NOx) generated from ammonia fuel.SOLUTION: There is provided a boiler in which an ammonia fuel burner 110 has an atomizer 111 that guides ammonia fuel toward a furnace along a second axial line X2 and injects the ammonia fuel from a tip end portion 111a. An injection quantity of the ammonia fuel injected from the tip end portion 111a toward one side closer to the center of the furnace than the second axial line X2 is greater than an injection quantity of the ammonia fuel injected from a plurality of second injection holes 111a2 toward the other side closer to a wall surface of the furnace than the second axial line X2.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present disclosure relates to combustion facilities, power generation facilities, and methods of operating combustion facilities. [Background technology]

[0002] Conventionally, a boiler that performs combined combustion of pulverized coal and ammonia has been known (see, for example, Patent Document 1). The boiler disclosed in Patent Document 1 is equipped with a triple-tube burner in which ammonia is supplied to an inner tube, pulverized coal is supplied to a central tube, and combustion air is supplied to an outer tube. The burner in Patent Document 1 injects pulverized coal so that a pulverized coal flame is formed closer to the furnace wall of the furnace than an ammonia flame caused by the combustion of ammonia. As a result, in Patent Document 1, when performing combined combustion of pulverized coal and ammonia, a decrease in the emissivity of the flame with respect to the furnace wall can be suppressed compared to when pulverized coal is burned as a sole fuel. Patent Document 1 discloses that the injection of pulverized coal is appropriately adjusted in order to suppress a decrease in the emissivity of the flame with respect to the furnace wall when performing combined combustion of pulverized coal and ammonia. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-173177 A Summary of the Invention [Problem to be solved by the invention]

[0004] When solid fuel such as pulverized coal and ammonia fuel containing ammonia are mixed and burned in a boiler, the nitrogen content (N) is oxidized during combustion of the ammonia fuel, generating nitrogen oxides (NOx). On the other hand, if ammonia is thermally decomposed into hydrogen (H2) and nitrogen (N2) before the nitrogen content (N) is oxidized during combustion of the ammonia fuel, NOx is less likely to be generated. This is because nitrogen (N2) is a stable molecule, and it is difficult for nitrogen (N2) to be converted into nitrogen oxides (NOx).

[0005] In Patent Document 1, the positions at which flames are formed by each fuel are different by different injection angles of pulverized coal and ammonia fuel. However, because the injection angles of each fuel are different, the air required for combustion of each fuel is not appropriately distributed to each flame position, and there is a risk that local high-oxygen or low-oxygen regions will be generated, resulting in the generation of nitrogen oxides (NOx). In addition, in a swirl combustion type combustion furnace in which the flame swirls and rises inside the furnace, it is possible that the flame or fuel jet will collide with the furnace wall, or that the swirl flame will not be formed stably.

[0006] The present disclosure has been made in consideration of the above circumstances, and aims to provide a combustion facility, a power generation facility, and an operating method for the combustion facility that are capable of suppressing the amount of nitrogen oxides (NOx) generated from ammonia fuel when both solid fuel and ammonia fuel are combusted in a furnace. [Means for solving the problem]

[0007] In order to solve the above problems, a combustion facility, a power generation facility, and a method of operating a combustion facility according to one embodiment of the present disclosure employ the following measures. A combustion device according to one aspect of the present disclosure includes a furnace formed by a plurality of wall surfaces installed along a vertical direction, a solid fuel combustion section attached to the wall surfaces and injecting solid fuel into the furnace to combust it, and an ammonia fuel combustion section attached to the wall surfaces and injecting ammonia fuel into the furnace to combust it, wherein the solid fuel combustion section and the ammonia fuel combustion section are disposed at the same position on the wall surfaces when the furnace is viewed in a plan view along the vertical direction, and the solid fuel combustion section is formed in a cylindrical shape extending along a first axis and is formed in a cylindrical shape extending along the first axis. the ammonia fuel combustion section has an ammonia fuel injection section that is formed in a cylindrical shape extending along a second axis parallel to the first axis and that guides the ammonia fuel along the second axis toward the furnace and injects the ammonia fuel from a tip, and an injection amount of the ammonia fuel injected from the tip to one side closer to the center of the furnace with respect to the second axis is greater than an injection amount of the ammonia fuel injected from the plurality of second injection holes to the other side closer to the wall surface with respect to the second axis.

[0008] In a method for operating a combustion device according to one aspect of the present disclosure, the combustion equipment includes a furnace formed by a plurality of wall surfaces installed along a vertical direction, a solid fuel combustion section attached to the wall surfaces and configured to inject solid fuel into the furnace for combustion, and an ammonia fuel combustion section attached to the wall surfaces and configured to inject ammonia fuel into the furnace for combustion, the solid fuel combustion section and the ammonia fuel combustion section being disposed at the same position on the wall surfaces when the furnace is viewed in a plan view along the vertical direction, and the solid fuel combustion section is formed in a cylindrical shape extending along a first axis and is configured to extend along the first axis. the ammonia fuel combustion unit has an ammonia fuel injection unit that is formed in a cylindrical shape so as to extend along a second axis parallel to the first axis and that guides the ammonia fuel along the second axis toward the furnace and injects the ammonia fuel from a tip thereof, and the ammonia fuel combustion unit includes an injection step of injecting the ammonia fuel such that an injection amount of the ammonia fuel injected from the tip to one side close to the center of the furnace with respect to the second axis is greater than an injection amount of the ammonia fuel injected to the other side close to the wall surface with respect to the second axis. Effect of the Invention

[0009] According to the present disclosure, it is possible to provide a combustion facility, a power generation facility, and an operating method for the combustion facility that are capable of suppressing the amount of nitrogen oxides (NOx) generated from ammonia fuel when both solid fuel and ammonia fuel are combusted in a furnace. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic configuration diagram showing a boiler according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a front view showing the combustion burner shown in FIG. [Diagram 3] FIG. 2 is a cross-sectional view showing an ammonia fuel burner included in the combustion burner shown in FIG. [Figure 4]FIG. 2 is a cross-sectional view showing a pulverized fuel burner of the combustion burner of the boiler shown in FIG. [Diagram 5] FIG. 4 is a partial enlarged view of the ammonia fuel burner shown in FIG. [Figure 6] FIG. 6 is a front view of the ammonia fuel burner of the combustion burner shown in FIG. 5, as viewed from the furnace side. [Figure 7] FIG. 7 is a partial enlarged view of the atomizer shown in FIG. [Figure 8] 8 is a cross-sectional view of the atomizer shown in FIG. 7 taken along the line AA. [Figure 9] FIG. 4 is a partial enlarged view showing a modified example of the atomizer of the ammonia fuel burner according to the first embodiment of the present disclosure. [Figure 10] FIG. 5 is a partial enlarged view of the pulverized fuel burner shown in FIG. [Figure 11] FIG. 6 is a partial enlarged view showing an atomizer of an ammonia fuel burner according to a second embodiment of the present disclosure. [Figure 12] 12 is a cross-sectional view of the atomizer shown in FIG. 11 taken along the line BB. [Figure 13] FIG. 11 is a partially enlarged view showing a modified example of an atomizer of the ammonia fuel burner according to the second embodiment of the present disclosure. [Figure 14] 14 is a cross-sectional view of the atomizer shown in FIG. 13 taken along the line CC. [Figure 15] FIG. 11 is a front view of an air nozzle of a combustion burner according to a third embodiment of the present disclosure, as viewed from the furnace side. [Figure 16] FIG. 16 is a cross-sectional view taken along the arrow DD of the air nozzle shown in FIG. 15. [Figure 17] FIG. 16 is a diagram showing a first modified example of the air nozzle shown in FIG. [Figure 18] FIG. 16 is a diagram showing a second modified example of the air nozzle shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] [First embodiment] A boiler (combustion equipment) 10 according to a first embodiment of the present disclosure will be described below with reference to the drawings. The boiler 10 according to this embodiment is a device that burns pulverized fuel (solid fuel) and ammonia fuel using a combustion burner and recovers heat generated by this combustion.

[0012] Fig. 1 is a schematic diagram showing a boiler 10 according to a first embodiment of the present disclosure. As shown in Fig. 1, the boiler 10 of this embodiment has a furnace 11, a combustion device 12 composed of a plurality of burners, and a flue 13. The furnace 11 has a hollow rectangular cylinder shape and is installed along the vertical direction, and the combustion device 12 is provided at the bottom of the furnace wall that constitutes this furnace 11.

[0013] The combustion device 12 has a plurality of combustion burners 100A, 100B, 100C, 100D, and 100E attached to the furnace wall. In this embodiment, the combustion burners 100A, 100B, 100C, 100D, and 100E are arranged in five sets (five stages) along the vertical direction, with four burners arranged at equal intervals along the circumferential direction around the central axis of the vertical direction along which the furnace 11 extends. Although five sets are used here, six sets or any other number of sets may be used.

[0014] Each of the combustion burners 100A, 100B, 100C, 100D, and 100E is connected to a pulverizer 31, 32, 33, 34, and 35 via a pulverizer fuel supply pipe 26, 27, 28, 29, and 30. The pulverizer 31, 32, 33, 34, and 35 pulverize solid carbonaceous fuel such as coal into pulverized fuel, and supply the pulverized fuel together with a carrier gas such as air to the pulverized fuel supply pipe 26, 27, 28, 29, and 30. The pulverized fuel is supplied from the pulverized fuel supply pipe 26, 27, 28, 29, and 30 to the combustion burners 100A, 100B, 100C, 100D, and 100E.

[0015] Each of the combustion burners 100A, 100B, 100C, 100D, and 100E is connected to an ammonia fuel supply unit 50 via an ammonia fuel supply pipe 51, 52, 53, 53, and 55. The ammonia fuel supply unit 50 supplies liquid or gas phase ammonia fuel containing ammonia as a component to the ammonia fuel supply pipes 51, 52, 53, 54, and 55. The ammonia fuel is supplied from the ammonia fuel supply pipes 51, 52, 53, 54, and 55 to the combustion burners 100A, 100B, 100C, 100D, and 100E.

[0016] The furnace 11 is provided with a wind box 36 at the mounting positions of the combustion burners 100A, 100B, 100C, 100D, and 100E, and one end of an air duct 37 is connected to the wind box 36, and a blower 38 is attached to the other end of the air duct 37. Furthermore, the furnace 11 is provided with an additional air nozzle 39 vertically above the mounting positions of the combustion burners 100A, 100B, 100C, 100D, and 100E.

[0017] An end of a branch air duct 40 branched off from the air duct 37 is connected to the additional air nozzle 39. Therefore, the combustion air sent by the blower 38 can be supplied from the air duct 37 to the wind box 36, and then from the wind box 36 to each of the combustion burners 100A, 100B, 100C, 100D, and 100E. In addition, the combustion air sent by the blower 38 can be supplied from the branch air duct 40 to the additional air nozzle 39.

[0018] A flue 13 is connected to the vertical upper part of the furnace 11, and this flue 13 is provided with superheaters 41, 42, reheaters 43, 44, and economizers 45, 46, 47, which are heat exchangers for recovering heat from the combustion gas, and heat is exchanged between the combustion gas generated by combustion in the furnace 11 and water or steam.

[0019] An exhaust gas pipe 48 through which the combustion gas that has undergone heat exchange is discharged as exhaust gas is connected to the downstream side of the gas flow of the flue 13. An air heater 49 is provided between the exhaust gas pipe 48 and the air duct 37, and heat is exchanged between the air flowing through the air duct 37 and the exhaust gas flowing through the exhaust gas pipe 48, thereby raising the temperature of the combustion air to be supplied to the combustion burners 100A, 100B, 100C, 100D, and 100E. A chimney (not shown) is provided at the downstream end of the exhaust gas pipe 48.

[0020] The combustion burners 100A, 100B, 100C, 100D, and 100E can form a flame by blowing pulverized fuel and ammonia fuel into the furnace 11 and blowing combustion air into the furnace 11 and igniting the fuel at this time. In the furnace 11, the pulverized fuel, ammonia fuel, and combustion air are combusted to generate a flame. When the flame is generated in a vertically lower region in the furnace 11, the combustion gas (exhaust gas) rises in the furnace 11 and is discharged into the flue 13.

[0021] Water supplied from a water supply pump (not shown) is preheated by economizers 45, 46, and 47, and then introduced into superheaters 41 and 42 through heat transfer tubes (not shown) that constitute the furnace wall, where superheated steam is generated by heat exchange with the combustion gas.

[0022] The superheated steam generated in the superheaters 41, 42 is supplied to a steam turbine (not shown) of a power plant (power generation facility). The steam turbine is connected to a generator, and generates electricity by driving the generator with the steam generated in the boiler 10. The steam turbine may be a multi-stage turbine including a low-pressure turbine that introduces steam discharged from the high-pressure turbine into reheaters 43, 44 of the boiler 10 and utilizes the resuperheated steam.

[0023] Next, the combustion device 12 will be described in detail. However, since the combustion burners 100A, 100B, 100C, 100D, and 100E constituting this combustion device 12 have almost the same configuration, only the combustion burner 100A located at the top will be described.

[0024] Fig. 2 is a front view showing the combustion burner 100A shown in Fig. 1. As shown in Fig. 2, the combustion burner 100A has an ammonia fuel burner (ammonia fuel combustion section) 110, a pair of pulverized fuel burners (solid fuel combustion sections) 120, and a pair of air nozzles 130. The ammonia fuel burner 110 is a device that injects ammonia fuel and combustion air around it into the furnace 11 to combust them. The pulverized fuel burner 120 is a device that injects a combustible fluid, which is a mixture of pulverized fuel and conveying air (primary air), into the furnace 11 and combustion air (secondary air) around it to combust them.

[0025] The air nozzle 130 is a device that supplies combustion air to the furnace 11. The configuration of the combustion burner 100A is not limited to this. For example, the number of each of the ammonia fuel burner 110, the pulverized fuel burner 120, and the air nozzle 130 may be one or three or more. The order of the ammonia fuel burner 110, the pulverized fuel burner 120, and the air nozzle 130 may be set arbitrarily.

[0026] 2, in the combustion burner 100A, the center position P1 of the ammonia fuel burner 110, the center position P2 of the pulverized fuel burner 120, and the center position P3 of the air nozzle 130 are located on an axis Z parallel to the vertical direction VD. The center position P1 of the ammonia fuel burner 110, the center position P2 of the pulverized fuel burner 120, and the center position P3 of the air nozzle 130 are located at the same position in the horizontal direction HD.

[0027] Fig. 3 is a cross-sectional view showing the ammonia-fueled burner 110 of the combustion burner 100A of the boiler 10 shown in Fig. 1. As shown in Fig. 3, the combustion burner 100A has ammonia-fueled burners 110a, 110b, 110c, and 110d attached to four wall surfaces 11a, 11b, 11c, and 11d that form the furnace 11. The wall surfaces 11a, 11b, 11c, and 11d are each installed along the vertical direction.

[0028] Branch pipes 51a, 51b, 51c, and 51d branched from an ammonia fuel supply pipe 51 are connected to the ammonia fuel burners 110a, 110b, 110c, and 110d, respectively. In addition, branch pipes 37a, 37b, 37c, and 37d branched from an air duct 37 are connected to the ammonia fuel burners 110a, 110b, 110c, and 110d, respectively.

[0029] The ammonia fuel burner 110a is installed on the wall surface (first wall surface) 11a, and is installed at a position close to the wall surface 11b among the wall surfaces (second wall surface) 11b and (third wall surface) 11d arranged to face the wall surface 11a at a position adjacent to the wall surface 11a. The ammonia fuel burner 110b is installed on the wall surface 11b, and is installed at a position close to the wall surface 11c among the wall surfaces 11a and 11c arranged to face the wall surface 11b at a position adjacent to the wall surface 11b.

[0030] The ammonia fuel burner 110c is installed on the wall surface 11c and is installed at a position close to the wall surface 11d among the wall surfaces 11d and 11b arranged to face the wall surface 11c at a position adjacent to the wall surface 11c. The ammonia fuel burner 110d is installed on the wall surface 11d and is installed at a position close to the wall surface 11a among the wall surfaces 11a and 11c arranged to face the wall surface 11d at a position adjacent to the wall surface 11d.

[0031] Therefore, each ammonia fuel burner 110a, 110b, 110c, 110d on each wall surface of the furnace 11 can inject ammonia fuel into the furnace 11 at a slight angle with respect to the center of the furnace 11, forming four flames F1, F2, F3, F4. The flames F1, F2, F3, F4 become swirling flame flows that swirl counterclockwise when viewed from above the furnace 11. Here, the flames swirl counterclockwise, but the ammonia fuel burners 110a, 110b, 110c, 110d may be arranged to become swirling flame flows that swirl clockwise.

[0032] Fig. 4 is a cross-sectional view showing the pulverized fuel burner 120 of the combustion burner 100A of the boiler 10 shown in Fig. 1. The combustion burner 100A has pulverized fuel burners 120a, 120b, 120c, and 120d attached to four wall surfaces 11a, 11b, 11c, and 11d that form the furnace 11, as shown in Fig. 4.

[0033] The pulverized fuel burners 120a, 120b, 120c, and 120d are respectively connected to branch pipes 26a, 26b, 26c, and 26d branched from the pulverized fuel supply pipe 26. In addition, the pulverized fuel burners 120a, 120b, 120c, and 120d are respectively connected to branch pipes 37a, 37b, 37c, and 37d branched from the air duct 37.

[0034] The pulverized fuel burner 120a is installed on the wall surface (first wall surface) 11a, and is installed at a position close to the wall surface 11b among the wall surface (second wall surface) 11b and the wall surface (third wall surface) 11d arranged opposite to the wall surface 11a at a position adjacent to the wall surface 11a. The pulverized fuel burner 120b is installed on the wall surface 11b, and is installed at a position close to the wall surface 11c among the wall surface 11a and the wall surface 11c arranged opposite to the wall surface 11b at a position adjacent to the wall surface 11b.

[0035] The pulverized fuel burner 120c is installed on the wall surface 11c and is installed at a position close to the wall surface 11d among the wall surfaces 11d and 11b arranged opposite the wall surface 11c at a position adjacent to the wall surface 11c. The pulverized fuel burner 120d is installed on the wall surface 11d and is installed at a position close to the wall surface 11a among the wall surfaces 11a and 11c arranged opposite the wall surface 11d at a position adjacent to the wall surface 11d.

[0036] Therefore, each of the pulverized fuel burners 120a, 120b, 120c, and 120d on each wall surface of the furnace 11 can inject pulverized fuel into the furnace 11 at a slight angle with respect to the center of the furnace 11, forming four flames F1, F2, F3, and F4. The flames F1, F2, F3, and F4 become swirling flame flows that swirl counterclockwise when viewed from above the furnace 11. Here, the flames swirl counterclockwise, but the pulverized fuel burners 120a, 120b, 120c, and 120d may be arranged to become swirling flame flows that swirl clockwise.

[0037] As shown in Figures 3 and 4, the ammonia fuel burner 110a and the pulverized fuel burner 120a are arranged at the same position on the wall surface 11a when the furnace 11 is viewed in a plan view along the vertical direction VD. Here, the injection angles of the fuels and the combustion air injected from the ammonia fuel burner 110a and the pulverized fuel burner 120a are the same. Also, the ammonia fuel burner 110b and the pulverized fuel burner 120b are arranged at the same position on the wall surface 11b when the furnace 11 is viewed in a plan view along the vertical direction VD. Here, the injection angles of the fuels and the combustion air injected from the ammonia fuel burner 110b and the pulverized fuel burner 120b are the same.

[0038] Moreover, the ammonia fuel burner 110c and the pulverized fuel burner 120c are arranged at the same position on the wall surface 11c when the furnace 11 is viewed in a plan view along the vertical direction VD. Here, the injection angles of the fuels and the combustion air injected from the ammonia fuel burner 110c and the pulverized fuel burner 120c are the same. Moreover, the ammonia fuel burner 110d and the pulverized fuel burner 120d are arranged at the same position on the wall surface 11d when the furnace 11 is viewed in a plan view along the vertical direction VD. Here, the injection angles of the fuels and the combustion air injected from the ammonia fuel burner 110d and the pulverized fuel burner 120d are the same.

[0039] Next, the ammonia fuel burner 110 of the combustion burner 100A of this embodiment will be described in detail with reference to the drawings. Fig. 5 is a partially enlarged view of the ammonia fuel burner 110 shown in Fig. 3. Fig. 6 is a front view of the ammonia fuel burner 110 of the combustion burner 100A shown in Fig. 5, seen from the furnace 11 side. Fig. 7 is a partially enlarged view of the atomizer 111 shown in Fig. 6. Fig. 8 is a cross-sectional view of the atomizer 111 shown in Fig. 7 taken along the line AA.

[0040] The ammonia fuel burner 110 of this embodiment is a device that injects and combusts ammonia fuel into the furnace 11. As shown in Fig. 5 and Fig. 6, the ammonia fuel burner 110 has an atomizer (ammonia fuel injection unit) 111, a primary air nozzle 112, and a secondary air nozzle 113.

[0041] The atomizer 111 is a device formed in a cylindrical shape along the axis X2, which atomizes liquid phase ammonia fuel and injects it directly toward the furnace 11. As shown in Fig. 5, the atomizer 111 guides ammonia fuel toward the furnace 11 along the axis X2 and injects the ammonia fuel from a tip 111a of the atomizer 111. As shown in Fig. 6 and Fig. 7, the tip 111a of the atomizer 111 facing the furnace 11 is formed with a plurality of first injection holes 111a1 and a plurality of second injection holes 111a2 that are arranged in the circumferential direction around the axis X2 and inject ammonia fuel into the furnace 11.

[0042] 6 and 7, the first injection holes 111a1 and the second injection holes 111a2 are arranged, for example, at eight locations at 45-degree intervals in the circumferential direction, but other arrangements are also possible. For example, they may be arranged at any locations other than eight locations. In addition, the arrangement intervals of the first injection holes 111a1 and the second injection holes 111a2 in the circumferential direction do not have to be equal.

[0043] 6 to 8, the first injection holes 111a1 and the second injection holes 111a2 are arranged in the horizontal direction HD to sandwich the axis X2 that is the central axis of the atomizer 111. In the horizontal direction HD, the multiple second injection holes 111a2 are arranged on one side closer to the center Ct (see FIG. 3) of the furnace 11 than the axis X2, and the multiple first injection holes 111a1 are arranged on the other side closer to the wall surface 11b than the axis X2.

[0044] As shown in Figures 5 and 8, a first injection angle θ1 formed by a first injection direction SD1 in which the first injection hole 111a1 injects ammonia fuel and the axis X2 is set to be smaller than a second spray angle θ2 formed by a second injection direction SD2 in which the second injection hole 111a2 injects ammonia fuel and the axis X2.

[0045] Since the first injection angle θ1 is smaller than the second spray angle θ2, the injection range of the ammonia fuel injected from the first injection hole 111a1 centered on the first injection direction SD1 is closer to the axis X2 than the injection range of the ammonia fuel injected from the second injection hole 111a2 centered on the second injection direction SD2. Therefore, the injection amount of the ammonia fuel guided from the first injection hole 111a1 to one side closer to the center Ct of the furnace 11 than the axis X2 becomes larger than the injection amount of the ammonia fuel guided from the second injection hole 111a2 to the other side closer to the wall surface 11b than the axis X2.

[0046] As a result, the injection amount (second injection amount) of the ammonia fuel injected from the tip portion 111a of the atomizer 111 to one side closer to the center Ct of the furnace 11 than the axis X2 becomes larger than the injection amount (first injection amount) of the ammonia fuel injected from the tip portion 111a to the other side closer to the wall surface 11b than the axis X2. The injection amount here does not only refer to the amount of fuel immediately after being injected from the first injection hole 111a1 and the second injection hole 111a2, but also includes the amount of fuel diffused after injection.

[0047] In each of the four sets of first injection holes 111a1 and second injection holes 111a2 arranged point symmetrically with respect to the axis X2, the injection range of the ammonia fuel injected from the first injection holes 111a1 centered on the first injection direction SD1 is closer to the axis X2 than the injection range of the ammonia fuel injected from the second injection holes 111a2 centered on the second injection direction SD2. As a result, the second injection amount becomes larger than the first injection amount.

[0048] The four sets of first injection holes 111a1 and second injection holes 111a2 have the same diameter, and each injection hole has the same opening area facing the furnace 11. The first injection angle θ1 and the second spray angle θ2 are set so that the ratio of the second injection amount to the first injection amount (21st injection amount / 1st injection amount) is 1.2 times or more and 4 times or less.

[0049] 5 and 6, a plurality of swirl vanes (swirlers) 111b are attached to the outer circumferential surface of the atomizer 111. The swirl vanes 111b are members that impart a swirling force to the combustion air (primary air) PA moving straight along the axis X2 when the combustion air PA passes through the swirl vanes 111b. The combustion air PA to which the swirling force has been imparted is mixed with the ammonia fuel injected from the first injection hole 111a1 and the second injection hole 111a2, whereby a flame of the ammonia fuel is stably formed.

[0050] The primary air nozzle 112 is a cylinder formed in a cylindrical shape extending along the axis X2 and disposed on the outer periphery of the atomizer 111. The primary air nozzle 112 forms a flow path for circulating the combustion air (primary air) PA between itself and the outer periphery of the atomizer 111, and supplies the combustion air (primary air) PA from the outside of the atomizer 111 along the axis X2 so as to be mixed with the ammonia fuel injected into the furnace 11.

[0051] The secondary air nozzle 113 is a cylinder formed in a cylindrical shape extending along the axis X2 and disposed on the outer periphery of the primary air nozzle 112. The secondary air nozzle 113 forms a flow path for circulating the secondary air SA between itself and the outer periphery of the primary air nozzle 112, and supplies the secondary air SA from the outside of the primary air nozzle 112 along the axis X2 to the periphery of the ammonia flame formed in the furnace 11.

[0052] In order to make the second injection amount of ammonia fuel injected from the tip 111a of the atomizer 111 to one side closer to the center Ct of the furnace 11 than the axis X2 larger than the first injection amount of ammonia fuel injected from the tip 111a to the other side closer to the wall surface 11b than the axis X2, a modification shown in Fig. 9 may be used. Fig. 9 is a partially enlarged view showing a modification of the atomizer 111 of the ammonia fuel burner 110 according to the first embodiment of the present disclosure. The injection amount here does not only refer to the amount of fuel immediately after being injected from the first injection hole 111a1 and the second injection hole 111a2, but also includes the amount of fuel diffused after injection.

[0053] 7 and 8, the first injection angle θ1 formed by the first injection direction SD1 in which the first injection hole 111a1 injects the ammonia fuel and the axis X2 is set to be smaller than the second spray angle θ2 formed by the second injection direction SD2 in which the second injection hole 111a2 injects the ammonia fuel and the axis X2. In contrast, the atomizer 111 of the modified example shown in FIG 9 sets the first injection angle θ1 and the second spray angle θ2 to the same angle.

[0054] In addition, the atomizer 111 of the modified example shown in Fig. 9 has the positions of the multiple first injection holes 111a1 arranged closer to the second injection holes 111a2 side than the atomizer 111 shown in Fig. 7. In this way, the injection range of the ammonia fuel injected from the first injection hole 111a1 centered on the first injection direction SD1 becomes closer to the axis line X2 than the injection range of the ammonia fuel injected from the second injection hole 111a2 centered on the second injection direction SD2.

[0055] Therefore, the injection amount of ammonia fuel guided from the first injection hole 111a1 to one side closer to the center Ct of the furnace 11 than the axis X2 becomes larger than the injection amount of ammonia fuel guided from the second injection hole 111a2 to the other side closer to the wall surface 11b than the axis X2. As a result, the second injection amount of ammonia fuel injected from the tip portion 111a of the atomizer 111 to one side closer to the center Ct of the furnace 11 than the axis X2 can be made larger than the first injection amount of ammonia fuel injected from the tip portion 111a to the other side closer to the wall surface 11b than the axis X2.

[0056] Next, the pulverized fuel burner 120 of the combustion burner 100A of this embodiment will be described in detail with reference to the drawings. Fig. 10 is a partially enlarged view of the pulverized fuel burner shown in Fig. 4. The pulverized fuel burner 120 of this embodiment is a device that injects pulverized fuel into the furnace 11 and burns it. As shown in Fig. 10, the pulverized fuel burner 120 has a pulverized fuel nozzle (solid fuel injection part) 121 and a secondary air nozzle 122.

[0057] The pulverized fuel nozzle 121 is a device that is formed in a cylindrical shape along an axis (first axis) X1 and that injects pulverized fuel carried by carrier air (primary air) CA into the furnace 11. As shown in Fig. 10, the pulverized fuel nozzle 121 injects the pulverized fuel together with the carrier air (primary air) CA toward the furnace 11 along the axis X1.

[0058] The secondary air nozzle 122 is a cylinder formed in a cylindrical shape extending along the axis X1 and disposed on the outer periphery of the pulverized fuel nozzle 121. The secondary air nozzle 122 forms a flow passage between the outer periphery of the pulverized fuel nozzle 121 and the secondary air nozzle 122, through which the secondary air SA flows, and supplies the secondary air SA from the outside of the pulverized fuel nozzle 121 along the axis X1 to the periphery of the pulverized fuel flame formed in the furnace 11.

[0059] The axis X2, which is the direction in which the atomizer 111 injects ammonia fuel toward the furnace 11, is an axis parallel to the axis X1, which is the direction in which the pulverized fuel nozzle 121 injects pulverized fuel toward the furnace 11. The axis X1 and the axis X2 are axes extending in the same position and in the same direction on a horizontal plane perpendicular to the vertical direction VD.

[0060] The boiler 10 of the present embodiment described above provides the following actions and effects. According to the boiler 10 of this embodiment, the pulverized fuel nozzle 121 of the pulverized fuel burner 120 injects pulverized fuel toward the furnace 11 along the axis X1, and the atomizer 111 of the ammonia fuel burner 110 injects ammonia fuel toward the furnace 11 along the axis X2 parallel to the axis X1. A plurality of first injection holes 111a1 and a plurality of second injection holes 111a2 for injecting ammonia fuel are formed in the tip portion 111a of the atomizer 111, and in the horizontal direction HD, the plurality of first injection holes 111a1 are arranged on the other side closer to the wall surface 11b than the axis X2, and the plurality of second injection holes 111a2 are arranged on one side closer to the center Ct of the furnace 11 than the axis X2.

[0061] According to the boiler 10 of this embodiment, the second injection amount of ammonia fuel injected from the tip 111a of the atomizer 111 to one side closer to the center Ct of the furnace 11 than the axis X2 is greater than the first injection amount of ammonia fuel injected from the tip 111a of the atomizer 111 to the other side closer to the wall surface 11b than the axis X2. Since the ammonia fuel injected from the atomizer 111 to the furnace 11 is guided more to one side (a relatively high temperature region in the horizontal cross section of the furnace 11) closer to the center Ct of the furnace 11 than the axis X2, ammonia is more likely to be thermally decomposed into hydrogen (H2) and nitrogen (N2), while the nitrogen content (N content) is less likely to be oxidized to generate nitrogen oxides (NOx) compared to the case where ammonia fuel is evenly guided to one side and the other side. As a result, when both pulverized fuel and ammonia fuel are burned in the furnace 11, the amount of nitrogen oxides (NOx) generated from ammonia fuel can be suppressed.

[0062] According to the boiler 10 of this embodiment, the ammonia fuel is directly injected into the furnace 11 so that the amount of injection toward one side closer to the center Ct of the furnace 11 than the axis X2 is greater (liquid phase ammonia fuel is atomized and injected), thereby promoting the thermal decomposition of ammonia into hydrogen (H2) and nitrogen (N2).

[0063] According to the boiler 10 of this embodiment, by setting the ratio of the second injection amount of ammonia fuel injected from the tip 111a of the atomizer 111 to one side relative to the first injection amount of ammonia fuel injected from the tip 111a of the atomizer 111 to the other side to be 1.2 times or more and 4 times or less, it is possible to appropriately suppress the amount of nitrogen oxides (NOx) generated from ammonia fuel when both pulverized fuel and ammonia fuel are combusted in the furnace 11.

[0064] According to the boiler 10 of this embodiment, the total area of ​​the multiple second injection holes 111a2 on one side closer to the center Ct of the furnace 11 than the axis X2 is equal to the total area of ​​the multiple first injection holes 111a1 on the other side closer to the wall surface 11b than the axis X2. Therefore, compared to the case where these total areas are different, which corresponds to the second embodiment described later, it is possible to suppress imbalance in the air-fuel ratio (ratio of combustion air and ammonia fuel), and it is possible to suppress an increase in the amount of NOx generated.

[0065] Second Embodiment Hereinafter, a boiler 10 according to a first embodiment of the present disclosure will be described with reference to the drawings. The second embodiment is a modified example of the first embodiment, and is the same as the first embodiment except as otherwise specifically described below, and therefore the description thereof will be omitted below.

[0066] In the first embodiment, the first injection angle θ1 formed by the first injection direction SD1 of the first injection hole 111a1 and the axis X2 is set to be smaller than the second spray angle θ2 formed by the second injection direction SD2 of the second injection hole 111a2 and the axis X2. In contrast, in the second embodiment, the first injection angle θ1 formed by the first injection direction SD1 of the first injection hole 111a1 and the axis X2 is set to be the same angle as the second spray angle θ2 formed by the second injection direction SD2 of the second injection hole 111a2 and the axis X2.

[0067] On the other hand, in the second embodiment, the second total value of the flow path cross-sectional area of ​​the multiple second injection holes 111a2 is made larger than the first total value of the flow path cross-sectional area of ​​the multiple first injection holes 111a1. As a result, the ammonia fuel injected from the atomizer 111 to the furnace 11 is guided more toward one side closer to the center Ct of the furnace 11 than the axis X2.

[0068] Fig. 11 is a partially enlarged view showing an atomizer 111 of an ammonia fuel burner 110 according to a second embodiment of the present disclosure. Fig. 12 is a cross-sectional view of the atomizer shown in Fig. 11 taken along the line BB. As shown in Figs. 11 and 12, a first inner diameter ID1 of a first injection hole 111a1 is smaller than a second inner diameter ID2 of a second injection hole 111a2. The number of the first injection holes 111a1 formed in a tip portion 111a of the atomizer 111 is the same as the number of the second injection holes 111a2 formed in the tip portion.

[0069] The first inner diameters ID1 of the four first injection holes 111a1 shown in Fig. 11 are the same, and the second inner diameters ID2 of the four second injection holes 111a2 shown in Fig. 11 are the same, but other configurations are also possible. For example, among the four second injection holes 111a2, two second injection holes 111a2 adjacent to the first injection hole 111a1 may be set to the second inner diameter ID2, and two second injection holes 111a2 distant from the first injection hole 111a1 may be set to the fourth inner diameter ID4 larger than the second inner diameter ID2. Also, among the four first injection holes 111a1, two first injection holes 111a1 adjacent to the second injection hole 111a2 may be set to the first inner diameter ID1, and two first injection holes 111a1 distant from the second injection hole 111a2 may be set to the third inner diameter ID3 smaller than the first inner diameter ID1. Also, the third inner diameter ID3 and the fourth inner diameter ID4 may be used in combination (see the dotted line shown in FIG. 11).

[0070] As shown in FIG. 12, a first injection angle θ1 formed by a first injection direction SD1 in which the first injection hole 111a1 injects ammonia fuel and an axis X2 is set to be the same as a second spray angle θ2 formed by a second injection direction SD2 in which the second injection hole 111a2 injects ammonia fuel and the axis X2.

[0071] According to the boiler 10 of the present embodiment, by making the first inner diameter ID1 of the first injection hole 111a1 smaller than the second inner diameter ID2 of the second injection hole 111a2, the second total value of the flow passage cross-sectional area of ​​the multiple second injection holes 111a2 can be made larger than the first total value of the flow passage cross-sectional area of ​​the multiple first injection holes 111a1. Therefore, the ammonia fuel injected from the tip portion 111a of the atomizer 111 to the furnace 11 can be guided more toward one side closer to the center Ct of the furnace 11 than the axis X2.

[0072] In this embodiment, the first inner diameter ID1 of the first injection hole 111a1 is smaller than the second inner diameter ID2 of the second injection hole 111a2, and the number of the multiple first injection holes 111a1 formed in the tip portion 111a is the same as the number of the multiple second injection holes 111a2 formed in the tip portion 111a, but this may be a modified example shown in Figures 13 and 14.

[0073] Fig. 13 is a partially enlarged view showing a first modified example of the atomizer 111 of the ammonia fuel burner 110 according to the second embodiment of the present disclosure. Fig. 14 is a cross-sectional view of the atomizer 111 shown in Fig. 13 taken along the CC arrow. As shown in Fig. 13 and Fig. 14, in the atomizer 111 of the modified example, the first inner diameter ID1 of the first injection hole 111a1 and the second inner diameter ID2 of the second injection hole 111a2 are the same.

[0074] As shown in Fig. 14, a first injection angle θ1 formed by a first injection direction SD1 in which the first injection hole 111a1 injects ammonia fuel and the axis X2 is set to be the same as a second spray angle θ2 formed by a second injection direction SD2 in which the second injection hole 111a2 injects ammonia fuel and the axis X2. As shown in Fig. 13, the number (7) of the multiple second injection holes 111a2 formed in the tip portion 111a of the atomizer 111 is greater than the number (4) of the multiple first injection holes 111a1 formed in the tip portion 111a.

[0075] According to the boiler 10 of the present embodiment, by making the number of the second injection holes 111a2 larger than the number of the first injection holes 111a1, the second total value of the flow passage cross-sectional area of ​​the multiple second injection holes 111a2 becomes larger than the first total value of the flow passage cross-sectional area of ​​the multiple first injection holes 111a1. Therefore, the ammonia fuel injected from the tip portion 111a of the atomizer 111 to the furnace 11 can be guided more toward one side closer to the center Ct of the furnace 11 than the axis X2.

[0076] According to the boiler 10 of this embodiment, the total area of ​​the multiple second injection holes 111a2 on one side closer to the center Ct of the furnace 11 than the axis X2 is larger than the total area of ​​the multiple first injection holes 111a1 on the other side closer to the wall surface 11b than the axis X2. Therefore, compared to the case where these total areas are equal in the first embodiment described above, more ammonia fuel can be injected to one side closer to the center Ct of the furnace 11 than the axis X2, and the injection amount can be largely biased.

[0077] Third Embodiment Next, a third embodiment of the present disclosure will be described. The third embodiment is a modified example of the first embodiment, and is the same as the first embodiment except as otherwise specifically described below, and the description below will be omitted. In the first embodiment, the liquid phase ammonia fuel is atomized by the atomizer 111 and directly injected toward the furnace 11. In contrast, in this embodiment, the ammonia fuel is mixed with the combustion air PA in the air nozzle 130A by the fuel nozzle 131A arranged in the air nozzle 130A, and the flammable gas in which the ammonia fuel and the combustion air PA are mixed is injected into the furnace 11.

[0078] Fig. 15 is a front view of an air nozzle 130A of a combustion burner according to a third embodiment of the present disclosure, as viewed from the furnace side. Fig. 16 is a cross-sectional view of the air nozzle 130A shown in Fig. 15 taken along the arrow DD. As shown in Figs. 15 and 16, the air nozzle 130A of this embodiment is formed in a cylindrical shape extending along an axis X3 parallel to the axis X1 and the axis X2, and is disposed outside the fuel nozzle 131A. The air nozzle 130A is a device that supplies combustion air PA from the outside of the fuel nozzle 131A along the axis X3.

[0079] The air nozzle 130A of this embodiment is disposed at the same position as the air nozzle 130 shown in Fig. 2. The combustion burner 100 of this embodiment has an ammonia fuel burner 110 shown in Fig. 2, a pair of pulverized fuel burners 120, and a pair of air nozzles 130A shown in Fig. 15. In this embodiment, ammonia fuel is injected from both the ammonia fuel burner 110 and the air nozzle 130, but the configuration may not include the ammonia fuel burner 110.

[0080] The fuel nozzle 131A is a device that is formed in a cylindrical shape (for example, a square cylindrical shape in a cross section as shown in FIG. 15) along the axis X3 and injects ammonia fuel into the air nozzle 130A. As shown in FIG. 15 and FIG. 16, the fuel nozzle 131A guides the ammonia fuel toward the furnace 11 along the axis X3 and injects the ammonia fuel from a tip 131Aa of the fuel nozzle 131A.

[0081] A plurality of first injection holes 131Aa1 and a plurality of second injection holes 131Aa2 for injecting ammonia fuel are arranged along the horizontal direction HD at a tip 131Aa of the fuel nozzle 131A on the furnace 11 side. The air nozzle 130A mixes the ammonia fuel injected by the fuel nozzle 131A in the air nozzle 130A with the combustion air PA and supplies the mixture to the furnace 11.

[0082] 15, in this embodiment, the first inner diameter ID1 of the first injection hole 131Aa1 is smaller than the second inner diameter ID2 of the second injection hole 131Aa2, and the number (three) of the multiple first injection holes 131Aa1 formed in the tip portion 131Aa is the same as the number (three) of the multiple second injection holes 131Aa2 formed in the tip portion 131Aa. The multiple first injection holes 131Aa1 and the multiple second injection holes 131Aa2 are disposed at positions symmetrical with respect to the axis X3 in the horizontal direction HD.

[0083] According to the boiler 10 of this embodiment, the first inner diameter ID1 of the first injection hole 131Aa1 is made smaller than the second inner diameter ID2 of the second injection hole 131Aa2, so that the second total value of the flow path cross-sectional area of ​​the multiple second injection holes 131Aa2 is larger than the first total value of the flow path cross-sectional area of ​​the multiple first injection holes 131Aa1. As a result, the first injection amount of ammonia fuel injected to one side close to the center Ct of the furnace 11 with respect to the axis X3 becomes larger than the first injection amount of ammonia fuel injected to the other side close to the wall surface 11b. The ratio of the second injection amount to the first injection amount (second injection amount / first injection amount) is set to be 1.2 times or more and 4 times or less.

[0084] The fuel nozzle 131A described above may be a first modified example shown in Fig. 17. Fig. 17 is a diagram showing a first modified example of the air nozzle 130A shown in Fig. 15. In the fuel nozzle 131A shown in Fig. 17, the first inner diameter ID1 of the first injection hole 131Aa1 is the same as the second inner diameter ID2 of the second injection hole 131Aa2. Also, the number (four) of the multiple second injection holes 131Aa2 formed in the tip portion 131Aa is greater than the number (three) of the multiple first injection holes 131Aa1 formed in the tip portion 131Aa.

[0085] According to the boiler 10 of this embodiment, the number of the second injection holes 131Aa2 is made larger than the number of the first injection holes 131Aa1, so that the second total value of the flow path cross-sectional area of ​​the multiple second injection holes 131Aa2 is larger than the first total value of the flow path cross-sectional area of ​​the multiple first injection holes 131Aa1. As a result, the second injection amount of ammonia fuel injected to one side close to the center Ct of the furnace 11 with respect to the axis X3 becomes larger than the first injection amount of ammonia fuel injected to the other side close to the wall surface 11b. The ratio of the second injection amount to the first injection amount (second injection amount / first injection amount) is set to be 1.2 times or more and 4 times or less.

[0086] The fuel nozzle 131A described above may be a second modified example shown in Fig. 18. Fig. 18 is a diagram showing a second modified example of the air nozzle 130A shown in Fig. 15. In the fuel nozzle 131A shown in Fig. 18, the first inner diameter ID1 of the first injection hole 131Aa1 is the same as the second inner diameter ID2 of the second injection hole 131Aa2. In addition, the number (three) of the multiple first injection holes 131Aa1 formed in the tip portion 131Aa is the same as the number (three) of the multiple second injection holes 131Aa2 formed in the tip portion 131Aa.

[0087] In a first modified example shown in Fig. 17, the center position in the horizontal direction HD of the air nozzle 130A and the center position in the horizontal direction HD of the fuel nozzle 131A are aligned with the position of the axis X3. On the other hand, in a second modified example shown in Fig. 18, the center position in the horizontal direction HD of the air nozzle 130A is aligned with the position of the axis X3, while the center position in the horizontal direction HD of the fuel nozzle 131A is aligned with the position on one side closer to the center Ct of the furnace 11 than the axis X3.

[0088] According to the boiler 10 of the present embodiment described above, ammonia fuel is injected into the air nozzle 130A so that the amount of injection toward one side closer to the center Ct of the furnace 11 with respect to the axis X3 is greater, thereby facilitating the thermal decomposition of the ammonia injected from the air nozzle 130A into the furnace 11 into hydrogen (H2) and nitrogen (N2).

[0089] The combustion equipment, the power generation equipment, and the method of operating the combustion equipment described in the above-described respective embodiments can be understood, for example, as follows. A combustion facility according to a first aspect of the present disclosure includes a furnace (11) formed by a plurality of wall surfaces (11a, 11b, 11c, 11d) installed along a vertical direction, a solid fuel combustion section (120) attached to the wall surfaces and configured to inject solid fuel into the furnace (11) for combustion, and an ammonia fuel combustion section (110) attached to the wall surfaces and configured to inject ammonia fuel into the furnace (11) for combustion, wherein the solid fuel combustion section and the ammonia fuel combustion section are disposed at the same position on the wall surfaces when the furnace is viewed in a plan view along the vertical direction, and the solid fuel combustion section is formed in a cylindrical shape extending along a first axis (X1). the ammonia fuel combustion section is formed in a cylindrical shape so as to extend along an axis (X2) parallel to the first axis (X1) and has an ammonia fuel injection section (111) that guides the ammonia fuel along the second axis toward the furnace and injects the ammonia fuel from a tip (111a), and a first injection amount of the ammonia fuel injected from the tip to one side close to the center of the furnace with respect to the second axis is greater than a second injection amount of the ammonia fuel injected to the other side close to the wall surface with respect to the second axis.

[0090] According to the combustion equipment of the first aspect of the present disclosure, the solid fuel injection unit of the solid fuel combustion unit injects solid fuel toward the furnace along a first axis, and the ammonia fuel injection unit of the ammonia combustion unit injects ammonia fuel toward the furnace along a second axis parallel to the first axis.

[0091] According to the combustion equipment according to the first aspect of the present disclosure, the injection amount of ammonia fuel injected from the tip to one side close to the center of the furnace with respect to the second axis is greater than the second injection amount of ammonia fuel injected from the tip to the other side close to the wall surface with respect to the second axis. Since the ammonia fuel injected from the ammonia fuel injection unit to the furnace is led to one side close to the center of the furnace with respect to the second axis in a larger amount, ammonia is more likely to be thermally decomposed into hydrogen (H2) and nitrogen (N2), while the nitrogen content (N content) is less likely to be oxidized to generate nitrogen oxides (NOx) compared to the case where ammonia fuel is led evenly to one side and the other side. This makes it possible to suppress the amount of nitrogen oxides (NOx) generated from ammonia fuel when both solid fuel and ammonia fuel are burned in the furnace.

[0092] The combustion equipment according to a second aspect of the present disclosure is the first aspect, further including the following configuration: That is, the ammonia fuel injection unit directly injects the ammonia fuel toward the furnace. According to the combustion equipment of the second aspect of the present disclosure, ammonia fuel is directly injected into the furnace so that the first injection amount is greater on one side closer to the center of the furnace relative to the second axis, thereby facilitating the thermal decomposition of ammonia into hydrogen (H2) and nitrogen (N2).

[0093] The combustion equipment according to a third aspect of the present disclosure is the first aspect, further including the following configuration: That is, the ammonia fuel combustion unit is formed in a cylindrical shape extending along the second axis and is arranged outside the ammonia fuel injection unit, has an air nozzle (130A) that supplies combustion air along the second axis from the outside of the ammonia fuel injection unit, and mixes the ammonia fuel injected by the ammonia fuel injection unit inside the air nozzle with the combustion air and supplies the mixture to the furnace.

[0094] According to the combustion equipment of the third aspect of the present disclosure, ammonia fuel is injected into the air nozzle so that the first injection amount is greater on one side closer to the center of the furnace relative to the second axis, thereby facilitating the thermal decomposition of the ammonia injected from the air nozzle into the furnace into hydrogen (H2) and nitrogen (N2).

[0095] The combustion equipment according to a fourth aspect of the present disclosure is the same as any one of the first to third aspects, and further includes the following configuration: That is, a plurality of first injection holes (111a1) and a plurality of second injection holes (111a2) for injecting the ammonia fuel are formed in the tip portion, a plurality of the second injection holes are arranged on one side close to a center (Ct) of the furnace with respect to the second axis in the horizontal direction, a plurality of the first injection holes are arranged on the other side with respect to the second axis, and a ratio of the injection amount of the ammonia fuel injected from the tip portion to one side close to the center of the furnace with respect to the second axis to the injection amount of the ammonia fuel injected to the other side close to the wall surface with respect to the second axis is 1.2 times or more and 4 times or less.

[0096] According to the combustion equipment of the fourth aspect of the present disclosure, by setting the ratio of the amount of ammonia fuel injected from the tip to one side closer to the center of the furnace relative to the second axis to the amount of ammonia fuel injected to the other side closer to the wall surface relative to the second axis to be 1.2 times or more and 4 times or less, it is possible to appropriately suppress the amount of nitrogen oxides (NOx) generated from ammonia fuel when both solid fuel and ammonia fuel are burned in the furnace.

[0097] The combustion equipment according to a fifth aspect of the present disclosure is the same as any one of the first to third aspects, and further includes the following configuration: That is, a plurality of first injection holes (111a1) and a plurality of second injection holes (111a2) for injecting the ammonia fuel are formed in the tip portion, a plurality of the second injection holes are arranged on one side close to a center (Ct) of the furnace with respect to the second axis in the horizontal direction, and a plurality of the first injection holes are arranged on the other side with respect to the second axis, and a first sum of flow path cross-sectional areas of the plurality of first injection holes is larger than a second sum of flow path cross-sectional areas of the plurality of second injection holes. According to the combustion equipment according to the fifth aspect of the present disclosure, by making the first total value of the flow path cross-sectional areas of the multiple first injection holes larger than the second total value of the flow path cross-sectional areas of the multiple second injection holes, it is possible to guide more of the ammonia fuel injected from the ammonia fuel injection unit into the furnace to one side closer to the center of the furnace with respect to the second axis.

[0098] The combustion equipment according to a sixth aspect of the present disclosure is the fifth aspect, further comprising the following configuration: That is, the number of the plurality of second injection holes formed in the tip portion is greater than the number of the plurality of first injection holes formed in the tip portion. According to the combustion equipment according to the sixth aspect of the present disclosure, by making the number of the second injection holes greater than the number of the first injection holes, it is possible to guide more of the ammonia fuel injected from the ammonia fuel injection unit to the furnace to one side closer to the center of the furnace with respect to the second axis.

[0099] The combustion equipment according to a seventh aspect of the present disclosure is the fifth aspect, further comprising the following configuration: a second inner diameter of the second injection hole is larger than a first inner diameter of the first injection hole, and the number of the plurality of first injection holes formed in the tip portion is the same as the number of the plurality of second injection holes formed in the tip portion. According to the combustion equipment according to the seventh aspect of the present disclosure, by making the second inner diameter of the second injection hole larger than the first inner diameter of the first injection hole, it is possible to guide more of the ammonia fuel injected from the ammonia fuel injection part to the furnace to one side closer to the center of the furnace with respect to the second axis.

[0100] A power generation facility according to an eighth aspect of the present disclosure includes any of the combustion facilities described above, a steam turbine driven by steam generated in the combustion facility, and a generator connected to the steam turbine. According to the power generation facility according to the eighth aspect of the present disclosure, when both the solid fuel and the ammonia fuel are combusted in the furnace, it is possible to suppress the amount of nitrogen oxides (NOx) generated from the ammonia fuel.

[0101] In a method for operating a combustion facility according to a ninth aspect of the present disclosure, the combustion facility includes a furnace formed by a plurality of wall surfaces installed along a vertical direction, a solid fuel combustion unit attached to the wall surfaces and injecting solid fuel into the furnace to combust it, and an ammonia fuel combustion unit attached to the wall surfaces and injecting ammonia fuel into the furnace to combust it, the solid fuel combustion unit and the ammonia fuel combustion unit being disposed at the same position on the wall surfaces when the furnace is viewed in a plan view along the vertical direction, and the solid fuel combustion unit is cylindrically shaped so as to extend along a first axis. the ammonia fuel combustion unit has a solid fuel injection unit formed in a cylindrical shape so as to extend along a second axis parallel to the first axis, and has an ammonia fuel injection unit that guides the ammonia fuel along the second axis toward the furnace and injects the ammonia fuel from a tip portion, and the ammonia fuel combustion unit includes an injection step of injecting the ammonia fuel such that an injection amount of the ammonia fuel injected from the tip portion to one side is greater than an injection amount of the ammonia fuel injected to the other side.

[0102] According to the combustion equipment operation method according to the ninth aspect of the present disclosure, when both solid fuel and ammonia fuel are combusted in a furnace, it is possible to suppress the amount of nitrogen oxides (NOx) generated from ammonia fuel. [Explanation of symbols]

[0103] 10 Boiler (combustion equipment) 11 Furnace 11a, 11b, 11c, 11d Wall 12 Combustion equipment 26 Fine fuel supply pipe 27,28,29,30 Fine fuel supply pipe 31, 32, 33, 34, 35 Crusher 36 Wind box 37 Air Duct 37a, 37b, 37c, 37d Branch pipe 38 Blower 39 Additional Air Nozzle 40 Branch air duct 50 Ammonia fuel supply unit 51, 52, 53, 54, 55 Ammonia fuel supply pipe 100, 100A, 100B, 100C, 100D, 100E Combustion burner 110, 110a, 110b, 110c, 110d Ammonia fuel burner (ammonia fuel combustion section) 111 Atomizer (ammonia fuel injection part) 131A Fuel nozzle (ammonia fuel injection part) 111a, 131Aa Tip 111a1,131Aa1 1st injection hole 111a2,131Aa2 2nd injection hole 111b Swirling blade 112 Primary air nozzle 113 Secondary Air Nozzle 120, 120a, 120b, 120c, 120d pulverized fuel burner (solid fuel combustion section) 121 Pulverized fuel nozzle 122 Secondary air nozzle 130,130A Air nozzle PA Combustion air (primary air) CA Conveying air (primary air) SA Secondary Air Ct center HD horizontal ID1 First inner diameter ID2 2nd inner diameter ID3 Third inner diameter SD1 1st injection direction SD2 2nd injection direction VD Vertical direction X1 axis (1st axis) X2 axis (second axis) X3, Z axis θ1 1st injection angle θ2 2nd spray angle

Claims

1. A furnace formed by a plurality of walls installed along a vertical direction; a solid fuel combustion unit attached to the wall surface and configured to inject and combust solid fuel into the furnace; an ammonia fuel combustion unit attached to the wall surface and injecting ammonia fuel into the furnace to combust it; the solid fuel combustion section and the ammonia fuel combustion section are disposed at the same position on the wall surface when the furnace is viewed in a plan view along the vertical direction, the solid fuel combustion unit is formed in a cylindrical shape so as to extend along a first axis line, and has a solid fuel injection unit that injects the solid fuel toward the furnace along the first axis line, the ammonia fuel combustion unit is formed in a cylindrical shape so as to extend along a second axis parallel to the first axis, and has an ammonia fuel injection unit that guides the ammonia fuel toward the furnace along the second axis and injects the ammonia fuel from a tip portion, Combustion equipment, wherein an injection amount of the ammonia fuel injected from the tip portion to one side closer to the center of the furnace with respect to the second axis is greater than an injection amount of the ammonia fuel injected to the other side closer to the wall surface with respect to the second axis.

2. The combustion facility according to claim 1 , wherein the ammonia fuel injection unit directly injects the ammonia fuel toward the furnace.

3. an air nozzle formed in a cylindrical shape extending along the second axis and disposed outside the ammonia fuel injection unit, the air nozzle supplying combustion air along the second axis from the outside of the ammonia fuel injection unit; 2. The combustion facility according to claim 1, wherein the air nozzle mixes the ammonia fuel injected by the ammonia fuel injection unit inside the air nozzle with the combustion air and supplies the mixed mixture to the furnace.

4. a plurality of first injection holes and a plurality of second injection holes for injecting the ammonia fuel are formed in the tip portion, In a horizontal direction, a plurality of the second injection holes are arranged on one side of the second axis line close to a center of the furnace, and a plurality of the first injection holes are arranged on the other side of the second axis line, 4. The combustion facility according to claim 1, wherein a ratio of an injection amount of the ammonia fuel injected from the tip portion to one side adjacent to a center of the furnace with respect to the second axis to an injection amount of the ammonia fuel injected to the other side adjacent to the wall surface with respect to the second axis is 1.2 times or more and 4 times or less.

5. a plurality of first injection holes and a plurality of second injection holes for injecting the ammonia fuel are formed in the tip portion, In a horizontal direction, a plurality of the second injection holes are arranged on one side of the second axis line close to a center of the furnace, and a plurality of the first injection holes are arranged on the other side of the second axis line, The combustion facility according to claim 1 , wherein a second sum of the flow path cross-sectional areas of the second injection holes is greater than a first sum of the flow path cross-sectional areas of the first injection holes.

6. The combustion facility according to claim 5 , wherein the number of the second injection holes is greater than the number of the first injection holes.

7. The combustion facility according to claim 5 , wherein the second inner diameter of the second injection hole is larger than the first inner diameter of the first injection hole.

8. A combustion facility according to any one of claims 1 to 7; A steam turbine driven by steam generated in the combustion facility; a generator coupled to the steam turbine.

9. A method for operating a combustion facility, comprising the steps of: The combustion facility includes: A furnace formed by a plurality of walls installed along a vertical direction; a solid fuel combustion unit attached to the wall surface and configured to inject and combust solid fuel into the furnace; an ammonia fuel combustion unit attached to the wall surface and injecting ammonia fuel into the furnace to combust it; the solid fuel combustion section and the ammonia fuel combustion section are disposed at the same position on the wall surface when the furnace is viewed in a plan view along the vertical direction, the solid fuel combustion unit is formed in a cylindrical shape so as to extend along a first axis line, and has a solid fuel injection unit that injects the solid fuel toward the furnace along the first axis line, the ammonia fuel combustion unit is formed in a cylindrical shape so as to extend along a second axis parallel to the first axis, and has an ammonia fuel injection unit that guides the ammonia fuel toward the furnace along the second axis and injects the ammonia fuel from a tip portion, A method for operating combustion equipment, comprising: an injection step of injecting the ammonia fuel such that an injection amount of the ammonia fuel injected from the tip portion to one side closer to a center of the furnace with respect to the second axis is greater than an injection amount of the ammonia fuel injected to the other side closer to the wall surface with respect to the second axis.

Images