WO2023053605A1 - Gas burner and combustion facility - Google Patents

Gas burner and combustion facility Download PDF

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Publication number
WO2023053605A1
WO2023053605A1 PCT/JP2022/024296 JP2022024296W WO2023053605A1 WO 2023053605 A1 WO2023053605 A1 WO 2023053605A1 JP 2022024296 W JP2022024296 W JP 2022024296W WO 2023053605 A1 WO2023053605 A1 WO 2023053605A1
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WIPO (PCT)
Prior art keywords
nozzle
hole
main
secondary air
gas burner
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Application number
PCT/JP2022/024296
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French (fr)
Japanese (ja)
Inventor
隆一郎 田中
俊一 津村
慎一 関口
富明 上妻
豊 冠木
洋平 高嶋
Original Assignee
三菱重工パワーインダストリー株式会社
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Publication of WO2023053605A1 publication Critical patent/WO2023053605A1/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C99/00—Subject-matter not provided for in other groups of this subclass
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/20—Non-premix gas burners, i.e. in which gaseous fuel is mixed with combustion air on arrival at the combustion zone
    • F23D14/22—Non-premix gas burners, i.e. in which gaseous fuel is mixed with combustion air on arrival at the combustion zone with separate air and gas feed ducts, e.g. with ducts running parallel or crossing each other

Definitions

  • the present disclosure relates to gas burners and combustion equipment for burning gaseous fuels containing hydrogen.
  • This application claims priority based on Japanese Patent Application No. 2021-160794 filed with the Japan Patent Office on September 30, 2021, the contents of which are incorporated herein.
  • Patent Literature 1 discloses a gas burner provided with a split-shaped flame stabilizer that is arranged on the central axis of the nozzle and widens toward the downstream side in the flow direction of the fuel gas.
  • a gas fuel containing hydrogen may be applied as a fuel for a gas burner.
  • Hydrogen has characteristics that are significantly different from the components contained in conventional fuels (for example, methane contained in city gas, propane contained in LPG, and pulverized coal contained in the fuel gas described in Patent Document 1). .
  • the technique described in Patent Literature 1 does not take the characteristics of hydrogen into consideration and does not provide a configuration that enhances flame stability or suppresses the generation of NOx.
  • the gas burner uses gas fuel containing hydrogen, there is room for improving the structure of the gas burner in consideration of the characteristics of hydrogen.
  • the present disclosure has been made in view of the above problems, and aims to provide a gas burner capable of achieving a suitable combustion state when using gas fuel containing hydrogen.
  • a gas burner according to the present disclosure is a gas burner for burning gas fuel containing hydrogen, wherein a main ejection part for ejecting the gas fuel includes at least one main hole. and a sub-ejection portion that ejects a smaller amount of the gas fuel than the main ejection portion and includes at least one sub-hole, formed at the tip of the nozzle; A primary air flow path portion that surrounds the periphery of the tip portion of the nozzle and forms a primary air outlet through which the primary air flows out in a front view viewed along the line, and a primary air flow path portion above the primary air outlet or in the front view a secondary air flow path portion positioned below and forming a secondary air outlet through which the secondary air flows, wherein in the front view, the ejection direction of the at least one secondary hole is aligned with the secondary air It is oriented transversely to the outlet, and the jetting direction of said at least one main hole is oriented non- transversely to said secondary air outlet.
  • gas burner of the present disclosure it is possible to achieve a favorable combustion state when using gas fuel containing hydrogen.
  • FIG. 4 is a diagram for explaining a flame stabilizing surface of the flame stabilizer according to the first embodiment;
  • Figure 4 illustrates a nozzle tip configuration according to some embodiments; It is a figure which shows the structure of the front-end
  • FIG. 11 is a diagram for explaining the layout of secondary air outlets according to the third embodiment;
  • 1 is a diagram schematically showing the internal configuration of a furnace according to some embodiments;
  • FIG. 1 is a diagram schematically showing the internal configuration of a furnace according to some embodiments;
  • FIG. 1 is a diagram schematically showing the internal configuration of a furnace according to some embodiments;
  • FIG. 1 is a diagram schematically showing the internal configuration of a furnace according to some embodiments;
  • FIG. 1 is
  • FIG. 1 is a diagram schematically showing the configuration of combustion equipment 1 according to the first embodiment.
  • the combustion facility 1 includes a furnace 2 and a gas burner 4 provided in the furnace 2 for burning gas fuel F containing hydrogen in the furnace 2 .
  • the combustion equipment 1 is, for example, a boiler, and generates a high-temperature exhaust gas G by burning the gas fuel F ejected from the gas burner 4 into the furnace 2 by generating a flame X, and from this high-temperature exhaust gas G Generates steam by recovering heat.
  • the heat of the exhaust gas G may be recovered by a heat exchanger provided inside the furnace 2 or may be recovered by a heat exchanger provided outside the furnace 2 .
  • gas fuel F containing hydrogen includes fuel containing hydrogen and fuel other than hydrogen (mixed combustion) and hydrogen only (single combustion), and further, fuel containing hydrogen and fuel other than hydrogen , hydrogen as the main fuel (50% or more by volume of hydrogen), and fuel other than hydrogen as the main fuel (less than 50% by volume of hydrogen).
  • gas fuel F containing hydrogen includes all of these cases.
  • FIG. 2 is a view schematically showing the internal configuration of the furnace 2 according to the first embodiment, and is a view of the furnace 2 viewed from the vertical direction.
  • the furnace 2 has a rectangular tubular shape with its longitudinal direction along the vertical direction.
  • the furnace 2 is formed with a combustion space 6 for burning the gas fuel F ejected from the gas burner 4 .
  • the combustion space 6 of this furnace 2 has a rectangular shape.
  • the furnace 2 has a first furnace wall 8 including a first inner peripheral surface 7a corresponding to one side of the rectangular combustion space 6 among the inner peripheral surfaces 7 of the furnace 2, and a first furnace wall 8 with the combustion space 6 interposed therebetween.
  • a second furnace wall 10 located on the opposite side of the first furnace wall 8; a third furnace wall 12 connecting one end portion 16 of the first furnace wall 8 and one end portion 18 of the second furnace wall 10; and a fourth furnace wall 14 connecting the other end 17 of the furnace wall 8 and the other end 19 of the second furnace wall 10 .
  • the third furnace wall 12 is located on the opposite side of the combustion space 6 from the fourth furnace wall 14 .
  • a combustion space 6 of the furnace 2 is formed in a rectangular shape by being surrounded by a first furnace wall 8, a second furnace wall 10, a third furnace wall 12, and a fourth furnace wall .
  • the furnace 2 is provided with a plurality of gas burners 4, as illustrated in FIG.
  • the plurality of gas burners 4 includes a first gas burner 4A (4) provided on the first furnace wall 8 so as to be closer to the fourth furnace wall 14 than the third furnace wall 12, A second gas burner 4B (4) provided on the second furnace wall 10 so as to be closer to the second furnace wall 10, and a third gas burner 4C provided on the third furnace wall 12 so as to be closer to the first furnace wall 8 than the second furnace wall 10 (4), and a fourth gas burner 4D (4) provided on the fourth furnace wall 14 so as to be closer to the second furnace wall 10 than to the first furnace wall 8.
  • Each of the plurality of gas burners 4 jets gas fuel F to rectangular corners 21 of the combustion space 6 .
  • the plurality of gas burners 4 may further include an upper gas burner stacked on the first gas burner 4A.
  • the gas burner 4 burns the gas fuel F.
  • the combustion facility 1 includes a gas fuel supply device 100 that supplies gas fuel F to the gas burner 4, and an air supply device 102 that supplies combustion air A to the gas burner 4. , further includes. Then, the gas burner 4 mixes the gas fuel F supplied from the gas fuel supply device 100 with the combustion air A supplied from the air supply device 102, and ejects the gas fuel into the furnace 2 (combustion space 6). Burn F.
  • the gas fuel supply device 100 connects a gas tank 104 in which gas fuel F is stored, the gas tank 104 and the gas burner 4, and supplies the gas fuel F stored in the gas tank 104 to the gas burner 4 so as to be circulated. lines 106 and .
  • the air supply device 102 includes an air supply line 108, one end of which is open to the atmosphere and the other end of which is connected to the gas burner 4, and an air supply line 108, which burns air taken in from one end of the air supply line 108.
  • a blower 110 for blowing air A to the furnace 2 is provided.
  • FIG. 3 is a diagram schematically showing the configuration of the gas burner 4 according to the first embodiment, and is a diagram (front view) of the gas burner 4 as seen from the combustion space 6 side of the furnace 2.
  • FIG. 4 is a view schematically showing the internal configuration of the gas burner 4 according to the first embodiment, and is a view of the gas burner 4 as seen along a left-right direction D3, which will be described later.
  • the direction in which the axis O of the nozzle 20 of the gas burner 4 extends is defined as the axial direction D1 of the nozzle 20.
  • the direction orthogonal to the vertical direction D2 is defined as the left-right direction D3.
  • the gas burner 4 includes a nozzle 20, a primary air flow path portion 22, a secondary air flow path portion 24, and a flame stabilizer 50.
  • the gas burner 4 is a rectangular burner whose front surface 5 facing the combustion space 6 of the furnace 2 has a longitudinal direction along the vertical direction D2. .
  • the nozzle 20 has, for example, a cylindrical shape centered on the axis O so that the gas fuel F can flow. Then, as illustrated in FIG. 4 , the nozzle 20 ejects the gas fuel F supplied from the gas fuel supply device 100 into the combustion space 6 of the furnace 2 . Specifically, as illustrated in FIG. 3 , a main ejection portion 28 and a sub-ejection portion 30 are formed at the tip portion 26 (burner tip) of the nozzle 20 . The main ejection part 28 ejects part of the gas fuel F supplied from the gas fuel supply device 100 into the combustion space 6 of the furnace 2, and the sub ejection part 30 is the remaining part of the gas fuel F supplied from the gas fuel supply device 100.
  • the secondary ejection part 30 is configured to eject a smaller amount of gas fuel F than the main ejection part 28 . That is, the amount of a portion of the gas fuel F ejected from the main ejection portion 28 is greater than the remaining amount of the gas fuel F ejected from the sub ejection portion 30 .
  • the main ejection portion 28 includes two main holes 32, as illustrated in FIG.
  • the first main hole 32A (32) is located on the opposite side of the second main hole 32B (32) across the axis O of the nozzle 20 in the left-right direction D3.
  • the first main hole 32A is located on the left side of the axis O of the nozzle 20, and the second main hole 32B is located on the right side of the axis O of the nozzle 20. As shown in FIG.
  • the sub ejection portion 30 includes two sub holes 34.
  • the first secondary hole 34A (34) is located on the opposite side of the axis O of the nozzle 20 from the second secondary hole 34B (34) in the vertical direction D2.
  • the first secondary hole 34A is located above the axis O of the nozzle 20, and the second secondary hole 34B is located below the axis O of the nozzle 20. As shown in FIG.
  • Each of the first main hole 32A and the second main hole 32B is located between the first secondary hole 34A and the second secondary hole 34B in the vertical direction D2.
  • Each of the first sub-hole 34A and the second sub-hole 34B is located between the first main hole 32A and the second main hole 32B in the left-right direction D3.
  • the first main hole 32A has a larger diameter than each of the first secondary hole 34A and the second secondary hole 34B.
  • the second main hole 32B has a larger diameter than each of the first secondary hole 34A and the second secondary hole 34B.
  • the first main hole 32A and the second main hole 32B have the same diameter.
  • the first secondary hole 34A and the second secondary hole 34B have the same diameter. In this way, the total opening area of the main holes 32 is larger than the total opening area of the sub-holes 34, so that the main jetting portion 28 can jet more fuel gas F than the sub-jetting portion 30 can.
  • the primary air flow path portion 22 extends around the tip portion 26 of the nozzle 20 in a front view (hereinafter referred to as “front view”) viewed along the axial direction D1 of the nozzle 20. surround.
  • the primary air flow path portion 22 forms a primary air outlet 36 through which the combustion air A supplied from the air supply device 102 flows out as the primary air A1.
  • the primary air flow path section 22 includes a primary air flow path 38 through which the primary air A1 supplied from the air supply device 102 flows.
  • the primary air flow path portion 22 (sleeve) has a cylindrical shape and extends along the axial direction D1 of the nozzle 20 .
  • the inner diameter of the primary air flow path portion 22 is larger than the outer diameter of the nozzle 20 , and the nozzle 20 is arranged within the primary air flow path portion 22 . That is, the primary air channel portion 22 includes the primary air channel 38 through which the primary air A1 flows between the inner wall surface of the primary air channel portion 22 and the outer wall surface of the nozzle 20 .
  • the primary air flow path 38 is formed around the outer circumference of the nozzle 20 .
  • the secondary air flow path portion 24 is positioned above or below the primary air outlet 36 in a front view, and the secondary air A2 is brought into contact with the gas fuel F later than the primary air A1. forms a secondary air outlet 40 through which .
  • the secondary air A2 may be the combustion air A supplied from the air supply device 102, or the circulating gas Eg obtained by circulating part of the exhaust gas G discharged from the furnace 2 to the furnace 2. good.
  • the secondary air A2 may be a mixture of the combustion air A and the circulating gas Eg.
  • the secondary air channel portion 24 includes an upper secondary air channel portion 24A (24) and a lower secondary air channel portion 24B (24).
  • a secondary air outlet 40 ⁇ /b>A ( 40 ) of the upper secondary air flow path portion 24 ⁇ /b>A is located above the primary air outlet 36 .
  • a secondary air outlet 40B (40) of the lower secondary air flow path portion 24B is located below the primary air outlet 36.
  • the secondary air outlet 40A of the upper secondary air channel portion 24A is located on the opposite side of the primary air outlet 36 from the secondary air outlet 40B of the lower secondary air channel portion 24B.
  • the secondary air outlet 40 includes an inner outlet 42 and an outer outlet 44 located further from the primary air outlet 36 than the inner outlet 42 . That is, the secondary air outlet 40A of the upper secondary air flow path portion 24A includes an inner outlet 42A (42) and an outer outlet 44A (44). The secondary air outlet 40B of the lower secondary air flow path portion 24B includes an inner outlet 42B (42) and an outer outlet 44B (44). In a front view, from above, the outer outlet 44A of the secondary air outlet 40A, the inner outlet 42A of the secondary air outlet 40A, the primary air outlet 36, the inner outlet 42B of the secondary air outlet 40B, and the secondary air outlet 40B are aligned with outer exits 44B.
  • the outer outlet 44 is configured so that the secondary air A2 flows out.
  • the combustion air A supplied from the air supply device 102 flows out from the outer outlet 44 as the secondary air A2.
  • the outer outlet 44 has a rectangular shape when viewed from the front, but the present disclosure is not limited to this shape.
  • the inner outlet 42 is configured so that low-oxygen secondary air A3 having a lower oxygen concentration than the secondary air A2 that flows out from the outer outlet 44 flows out.
  • the low-oxygen secondary air A3 is a circulating gas Eg obtained by circulating part of the exhaust gas G flowing out of the furnace 2 to the furnace 2 .
  • the inner outlet 42 has a rectangular shape when viewed from the front, but the present disclosure is not limited to this shape.
  • the ejection direction D4 of the main hole 32 is oriented in a direction that does not intersect the secondary air outlet 40 when viewed from the front. Furthermore, when viewed from the front, the ejection direction D5 of the secondary holes 34 is oriented in a direction intersecting with the secondary air outlet 40 .
  • the ejection direction D4 of the first main hole 32A is leftward
  • the ejection direction D4 of the second main hole 32B is rightward.
  • the ejection direction D5 of the first secondary hole 34A is upward
  • the ejection direction D5 of the second secondary hole 34B is downward.
  • FIG. 5 is a diagram for explaining the ejection direction D4 of the main hole 32 according to the first embodiment, and is a diagram of the tip portion 26 of the nozzle 20 viewed along the vertical direction D2.
  • FIG. 6 is a diagram for explaining the ejection direction D5 of the secondary hole 34 according to the first embodiment, and is a diagram of the tip portion 26 of the nozzle 20 viewed along the left-right direction D3.
  • the tip 26 of the nozzle 20 includes a flat first end face 37 facing left or right.
  • the first end face 37 connects the tip face 41 on the farthest one side (the combustion space 6 side) of the tip portion 26 of the nozzle 20 in the axial direction D ⁇ b>1 and the side face 43 .
  • the main hole 32 is formed in this first end face 37 , and the ejection direction D4 of the main hole 32 is a direction perpendicular to this first end face 37 .
  • the angle formed by the ejection direction D4 of the main hole 32 and the axial direction D1 of the nozzle 20 is defined as ⁇ 1.
  • the tip 26 of the nozzle 20 includes a flat second end surface 39 facing upwards or downwards.
  • the second end surface 39 connects the tip surface 41 and the side surface 43 of the tip portion 26 of the nozzle 20 .
  • the secondary hole 34 is formed in this second end face 39 , and the ejection direction D ⁇ b>5 of the secondary hole 34 is perpendicular to this second end face 39 .
  • the angle formed by the ejection direction D5 of the secondary hole 34 and the axial direction D1 of the nozzle 20 is ⁇ 2. In the first embodiment, ⁇ 1 ⁇ 2 is satisfied.
  • the flame stabilizer 50 is provided at the tip 26 of the nozzle 20 and has a flame stabilization surface 52 that separates from the axis O of the nozzle 20 toward the primary air outlet 36, as illustrated in FIG.
  • the flame stabilizer 50 includes a plurality of vanes 54 extending radially outward from the tip 26 of the nozzle 20 about the axis O of the nozzle 20 .
  • the plurality of blades 54 are arranged side by side along the circumferential direction around the axis O of the nozzle 20 . For example, 15 blades 54 are arranged at intervals of 24 degrees along the circumferential direction.
  • the flame stabilizer 50 is a vane-type flame stabilizer (so-called swirler) including a plurality of blades 54, but the present disclosure is not limited to this form.
  • the flame stabilizer 50 is a dish-type flame stabilizer (so-called diffuser) that includes a plate portion surrounding the tip 26 of the nozzle 20 . A hole into which the tip portion 26 of the nozzle 20 is fitted is formed in the plate portion.
  • the flame stabilization surface 52 of the flame stabilizer 50 is the surface of the plate portion on one side (combustion space 6 side) of the nozzle 20 in the axial direction D1.
  • FIG. 7 is a diagram for explaining the flame stabilization surface 52 of the flame stabilizer 50 according to the first embodiment.
  • the flame stabilizing surface 52 is the trailing edge 53 of the blade 54 facing one side (the combustion space 6 side) of the nozzle 20 in the axial direction D1.
  • the angle formed by the trailing edge 53 of the blade 54 and the axial direction D1 of the nozzle 20 is ⁇ 3, ⁇ 2 ⁇ 3 is satisfied.
  • the angle ⁇ 31 formed by the tangent line 59 passing through the contact point P and the axis O of the nozzle 20 is defined as P being the point of contact between the trailing edge 53 of the blade 54 and the tip 26 of the nozzle 20 . satisfies ⁇ 2 ⁇ 31.
  • the ejection direction D5 of the secondary hole 34 is oriented in a direction that intersects the secondary air outlet 40 when viewed from the front. Therefore, the small amount of gas fuel F ejected from the secondary hole 34 is quickly brought into contact with the secondary air A2 or the low-oxygen secondary air A3 flowing out from the secondary air outlet 40, thereby improving flame stability. can. In other words, flame stability can be ensured with a small amount of gas fuel F.
  • the ejection direction D4 of the main hole 32 is oriented in a direction that does not cross the secondary air outlet 40 when viewed from the front. Therefore, a large amount of the gas fuel F jetted from the main hole 32 is delayed from the gas fuel F jetted from the secondary hole 34, and the secondary air A2 or the low-oxygen secondary air flowing out from the secondary air outlet 40 is discharged. Make contact with A3. That is, the gaseous fuel F ejected from the main hole 32 flows into a region having a relatively low oxygen concentration spaced apart from the tip portion 26 of the nozzle 20 to one side in the axial direction D1 (the depth side of the combustion space 6).
  • the mixture of hydrogen and oxygen is moderated, slow combustion is promoted, temperature rise in the combustion space 6 is suppressed, and the generation of NOx can be suppressed. Therefore, it is possible to achieve a favorable combustion state (ensure flame stabilization and suppress NOx generation) when using a gas fuel containing hydrogen.
  • the low-oxygen secondary air A3 is discharged from the inner outlet 42, and the secondary air A2 is discharged from the outer outlet 44. Therefore, the low-oxygen secondary air A3 flowing out from the inner outlet 42 prior to the secondary air A2 flowing out from the outer outlet 44 is brought into contact with the gas fuel F ejected from the main hole 32 . Therefore, the mixture of hydrogen and oxygen can be made more gentle, and the temperature rise in the combustion space 6 can be further suppressed.
  • the ejection direction D4 of the first main hole 32A is leftward, and the ejection direction D4 of the second main hole 32B is rightward. Therefore, the nozzle 20 (main ejection portion 28) can eject the gas fuel F widely into the combustion space 6 in the left-right direction D3.
  • the ejection direction D5 of the first secondary hole 34A is upward, and the ejection direction D5 of the second secondary hole 34B is downward. Therefore, the nozzle 20 (sub-injection portion 30) can widely inject the gas fuel F into the combustion space 6 in the vertical direction D2.
  • the contact between a small amount of gaseous fuel F ejected from the secondary hole 34 and the secondary air A2 or low-oxygen secondary air A3 flowing out from the secondary air outlet 40 can be delayed.
  • ⁇ 1 ⁇ 2 and 15 degrees ⁇ 1 ⁇ 45 degrees are satisfied. If ⁇ 1 exceeds 45 degrees, the momentum of the gas fuel F ejected to one side in the axial direction D1 decreases, and the supply of the gas fuel F to the depth side of the combustion space 6 may become insufficient. In this case, local variations in the heat release rate occur within the combustion space 6, and combustion oscillation is more likely to occur. That is, the potential for combustion oscillation due to pressure fluctuations in the combustion space 6 increases. Further, when ⁇ 1 is less than 15 degrees, the flame becomes excessively long, which affects the heat absorption characteristics. Therefore, by satisfying 15° ⁇ 1 ⁇ 45°, it is possible to suppress the combustion oscillation, and to suppress the temperature rise of the combustion space 6 by slow combustion due to moderate lengthening of the flame.
  • ⁇ 1 ⁇ 2 and 35 degrees ⁇ 2 ⁇ 55 degrees are satisfied. If ⁇ 2 exceeds 55 degrees, the flame stabilizing properties in the vicinity of the flame stabilizer 50 become too strong, which may increase the burnout potential of the flame stabilizer 50 and accelerate the generation of NOx. Further, when ⁇ 2 is less than 35 degrees, the flame stabilization effect of the flame stabilizer 50 is weakened and the vibration potential is increased. By satisfying 35 degrees ⁇ 2 ⁇ 55 degrees, combustion oscillation, damage to the flame stabilizer 50, and generation of NOx can be suppressed in a well-balanced manner.
  • the tip 26 of the nozzle 20 is formed with one or more primary holes 32 .
  • tip 26 of nozzle 20 is formed with one or more secondary holes 34 .
  • FIG. 8 is a diagram showing the configuration of the tip portion 26 of the nozzle 20 according to some embodiments.
  • the primary ejection section 28 includes a plurality of primary holes 32 that are greater in number than the secondary holes 34 . In this case, even if the main hole 32 is smaller in diameter than the secondary hole 34 or has the same diameter as the secondary hole 34 , the main ejection portion 28 can eject more gas fuel F than the secondary ejection portion 30 .
  • FIG. 9 is a diagram showing the configuration of the tip portion 26 of the nozzle 20 according to the second embodiment.
  • the main hole 32 has an elliptical shape with its longitudinal direction extending along the vertical direction D2 when viewed from the front.
  • L the length of the major axis (longitudinal direction) of the main hole 32
  • W the length of the minor axis (lateral direction) of the main hole 32
  • the primary air A1 or the secondary air A2 is prevented from flowing into the radially inner region R (see FIG. 9) of the nozzle 20 from the gas fuel F ejected from the main hole 32. can be done. That is, it is possible to delay the mixing of hydrogen and oxygen and further suppress the generation of NOx.
  • the main hole 32 has an elliptical shape in the second embodiment, the present disclosure is not limited to this shape.
  • the main hole 32 has an arc shape (blade shape).
  • the shape of the main hole 32 is a camber line passing through one longitudinal end 60 of the main hole 32 and the other longitudinal end 62 of the main hole 32 and protruding in the opposite direction to the axis O of the nozzle 20. 63 (center line).
  • a line connecting one end 60 and the other end 62 of the main hole 32 and located on the opposite side of the axis O side of the nozzle 20 from the camber line 63 is defined as an outer line 64.
  • a line located on the side of the axis O of the nozzle 20 is defined as an inner line 66 .
  • W be the length of the longest straight line 70 among the straight lines that intersect the camber line 63 and connect the outer line 64 and the inner line 66
  • L be the length of the camber line 63, then 2 ⁇ W ⁇ L. Fulfill.
  • a gas burner 4 according to a third embodiment of the present disclosure will be described.
  • the ejection direction D4 of the main hole 32 is oriented in a direction intersecting the secondary air outlet 40 unlike the first embodiment.
  • Components that are the same as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.
  • FIG. 11 is a diagram schematically showing the configuration of the gas burner according to the third embodiment.
  • the main jet 28 includes two main holes 32, as illustrated in FIG.
  • the first main hole 32C (32) is located on the opposite side of the axis O of the nozzle 20 from the second main hole 32D (32) in the vertical direction D2.
  • the first main hole 32C is positioned above the axis O of the nozzle 20, and the second main hole 32D is positioned below the axis O of the nozzle 20.
  • FIG. 11 is a diagram schematically showing the configuration of the gas burner according to the third embodiment.
  • the main jet 28 includes two main holes 32, as illustrated in FIG.
  • the first main hole 32C (32) is located on the opposite side of the axis O of the nozzle 20 from the second main hole 32D (32) in the vertical direction D2.
  • the first main hole 32C is positioned above the axis O of the nozzle 20, and the second main hole 32D is positioned below the axis O of the nozzle 20.
  • the sub ejection portion 30 includes two sub holes 34.
  • the first secondary hole 34C (34) is located on the opposite side of the axis O of the nozzle 20 from the second secondary hole 34D (34) in the horizontal direction D3.
  • the first secondary hole 34C is located on the left side of the axis O of the nozzle 20, and the second secondary hole 34D is located on the right side of the axis O of the nozzle 20. As shown in FIG.
  • Each of the first main hole 32C and the second main hole 32C is located between the first secondary hole 34C and the second secondary hole 34D in the horizontal direction D3.
  • Each of the first secondary hole 34C and the second secondary hole 34D is positioned between the first primary hole 32C and the second primary hole 32D in the vertical direction D2.
  • the first main hole 32C has a larger diameter than each of the first secondary hole 34C and the second secondary hole 34D.
  • the second main hole 32D has a larger diameter than each of the first secondary hole 34C and the second secondary hole 34D.
  • the first main hole 32C and the second main hole 32D have the same diameter.
  • the first secondary hole 34C and the second secondary hole 34D have the same diameter. In this way, the total opening area of the main holes 32 is larger than the total opening area of the sub-holes 34, so that the main jetting portion 28 can jet more fuel gas F than the sub-jetting portion 30 can.
  • the ejection direction D4 of the main hole 32 is oriented in a direction that intersects the secondary air outlet 40 when viewed from the front.
  • the ejection direction D4 of the first main holes 32C is upward, and the ejection direction D4 of the second main holes 32D is downward.
  • the ejection direction D5 of the first secondary hole 34C is leftward, and the ejection direction D5 of the second secondary hole 34D is rightward.
  • the tip 26 of the nozzle 20 is aligned with the axis O of the nozzle 20 so that the ejection direction D4 of the main hole 32 can be switched to be oriented transversely to the secondary air outlet 40 or not. is configured to be rotatable around the center.
  • FIG. 12 is a diagram for explaining the layout of the secondary air outlet 40 according to the third embodiment.
  • an imaginary line 72 is linearly extended from the axis O of the nozzle 20 along the vertical direction D2.
  • a first crossing point 74 is a point where the imaginary line 72 intersects the periphery of the primary air outlet 36 .
  • the point at which the imaginary line 72 first intersects the periphery of the secondary air outlet 40 is defined as a second intersection point 76 .
  • the second intersection point 76 is the point at which the imaginary line 72 first intersects the perimeter of the inner outlet 42 . If the distance between the first intersection 74 and the axis O of the nozzle 20 is r, and the distance between the second intersection 76 and the axis O of the nozzle 20 is d, 2 ⁇ r ⁇ d is satisfied.
  • the secondary air outlet 40 is separated from the tip portion 26 of the nozzle 20 so as to satisfy 2 ⁇ r ⁇ d. Contact with the secondary air A2 or the low-oxygen secondary air A3 flowing out from the secondary air outlet 40 can be delayed. Therefore, by slowing down the mixing of hydrogen and oxygen, it is possible to suppress the temperature rise in the combustion space 6 and suppress the generation of NOx.
  • the furnace 2 has a rectangular combustion space 6 and each of the four gas burners 4 is positioned at a rectangular corner 21 of the combustion space 6 as illustrated and described in FIG. , the present disclosure is not limited to this form.
  • Figures 13A, 13B, and 13C is a diagram schematically showing the internal configuration of a furnace 2 according to some embodiments.
  • each of the four gas burners 4 has a flame X extending from the center of the combustion space 6 when the furnace 11 is viewed from above.
  • the first gas burner 4A is arranged on the wall surface of the first furnace wall 8 .
  • the second gas burner 4B is arranged on the wall surface of the second furnace wall 10 .
  • a third gas burner 4 ⁇ /b>C is arranged on the wall surface of the third furnace wall 12 .
  • a fourth gas burner 4 ⁇ /b>D is arranged on the wall surface of the fourth furnace wall 14 .
  • the combustion space 6 has an octagonal shape, as illustrated in FIG. 13B.
  • the furnace 2 includes a first corner portion 82 connecting one end portion 16 of the first furnace wall 8 and one end portion 80 of the third furnace wall 12 on the first furnace wall 16 side, and a second furnace wall of the third furnace wall 12.
  • a second corner portion 86 connecting the other end portion 84 on the side of the wall 10 and the one end portion 18 of the second furnace wall 10, the other end portion 19 of the second furnace wall 10 and the second furnace wall of the fourth furnace wall 14 A third corner portion 90 connecting the other end portion 88 on the 10th side, and a third corner portion 90 connecting the one end portion 92 of the fourth furnace wall 14 on the side of the first furnace wall 8 and the other end portion 17 of the first furnace wall 8 . 4 corners 94 .
  • the combustion space 6 of the furnace 2 includes a first furnace wall 8, a second furnace wall 10, a third furnace wall 12, a fourth furnace wall 14, a first corner portion 82, a second corner portion 86, a third corner portion 90 and It is formed in an octagonal shape by being surrounded by the fourth corner portion 94 .
  • the first gas burner 4A is arranged on the wall surface of the fourth corner portion 94 .
  • the second gas burner 4B is arranged on the wall surface of the second corner portion 86 .
  • the third gas burner 4C is arranged on the wall surface of the first corner portion 82 .
  • the fourth gas burner 4D is arranged on the wall surface of the third corner portion 90. As shown in FIG.
  • the combustion space 6 has a rectangular shape, as illustrated in FIG. 13C.
  • the first furnace wall 8 and the second furnace wall 10 each form a rectangular short side of the combustion space 6, and the third furnace wall 12 and the fourth furnace wall 14 each form a combustion chamber. It forms the rectangular long side of the space 6 .
  • Eight gas burners 4 are provided in the furnace 2, and the four gas burners 4 are arranged so that the flame X performs swirling combustion. In the form illustrated in FIG. 13 , two flames X are performing swirling combustion with eight gas burners 4 .
  • Each of the eight gas burners 4 is arranged on either the wall surface of the third furnace wall 12 or the wall surface of the fourth furnace wall 14 .
  • the gas burner (4) is A gas burner for burning gas fuel (F) containing hydrogen, A main ejection portion (28) for ejecting the gas fuel, the main ejection portion including at least one main hole (32), and a sub ejection portion (30) for ejecting a smaller amount of the gas fuel than the main ejection portion.
  • the primary air flow path surrounds the tip of the nozzle and forms a primary air outlet (36) through which the primary air (A1) flows out.
  • the ejection direction (D5) of the at least one secondary hole is oriented in a direction intersecting the secondary air outlet, and the ejection direction (D4) of the at least one main hole is the secondary air outlet. Oriented in a direction that does not intersect the outlet.
  • Hydrogen has a higher combustion speed than the components contained in conventional gas fuel. Therefore, when the gas fuel contains hydrogen, the amount of gas fuel used for flame stabilization of the gas burner can be reduced. On the other hand, since the hydrogen and oxygen are rapidly mixed, the temperature of the combustion space where the gas fuel is burned quickly rises, promoting the generation of nitrogen oxides (NOx). According to the configuration described in [1] above, a small amount of gas fuel ejected from the secondary hole of the secondary ejection portion is brought into rapid contact with the secondary air flowing out from the secondary air outlet, thereby improving flame stability. be able to. That is, it is possible to ensure flame stability with a small amount of gas fuel.
  • a large amount of gas fuel ejected from the main hole of the main ejection portion contacts the secondary air flowing out from the secondary air outlet later than the gas fuel ejected from the secondary hole.
  • the gaseous fuel ejected from the main hole flows into a region of relatively low oxygen concentration separated from the tip of the nozzle. Therefore, the mixture of hydrogen and oxygen is moderated, and slow combustion is promoted, thereby suppressing the temperature rise in the combustion space and suppressing the generation of NOx. Therefore, it is possible to achieve a favorable combustion state (ensure flame stabilization and suppress NOx generation) when using a gas fuel containing hydrogen.
  • said secondary air outlet includes an inner outlet (42) and an outer outlet (44) located further from said primary air outlet than said inner outlet; the outer outlet is configured to allow the secondary air to flow out; The inner outlet is configured to flow out low-oxygen secondary air (A3) having a lower oxygen concentration than the secondary air flowing out from the outer outlet.
  • A3 low-oxygen secondary air
  • the low-oxygen secondary air flowing out from the inner outlet prior to the secondary air flowing out from the outer outlet is brought into contact with the hydrogen gas fuel ejected from the main hole. Therefore, the mixture of hydrogen and oxygen can be made more moderate, and the temperature rise in the combustion space can be further suppressed.
  • ⁇ 1 be an angle formed by the ejection direction of the main hole and the axial direction of the nozzle when the tip of the nozzle is viewed in the vertical direction (D2)
  • D2 An angle formed by the ejection direction of the secondary hole and the axial direction of the nozzle when the tip of the nozzle is viewed along a direction perpendicular to each of the axial direction and the vertical direction of the nozzle. is ⁇ 2, It satisfies ⁇ 1 ⁇ 2.
  • the gas fuel ejected from the secondary hole of the secondary ejection portion (more specifically, the flame generated by the contact between the gas fuel ejected from the secondary hole and the primary air) It is possible to suppress damage to the flame stabilizer due to
  • the at least one main hole has a longitudinal shape, and the length in the longitudinal direction of the at least one main hole is L, and the length in the short direction of the at least one main hole is W. , 2 ⁇ W ⁇ L is satisfied.
  • the main ejection part includes the at least one main hole having a larger diameter than the at least one secondary hole.
  • the main ejection part can eject a larger amount of gas fuel than the sub ejection part.
  • the main ejection part includes the plurality of main holes, which is greater than the number of the at least one secondary holes.
  • the main ejection portion can eject a larger amount of gas fuel than the sub ejection portion.
  • the at least one main hole includes a first main hole (32A) and a second main hole (32B);
  • the first main hole is located on the opposite side of the second main hole across the axis of the nozzle in the left-right direction (D3),
  • the ejection direction of the first main holes is oriented so as to be opposite to the ejection direction of the second main holes.
  • the main ejection portion can eject the gas fuel widely in the left-right direction.
  • the at least one subhole includes a first subhole (34A) and a second subhole (34B);
  • the first secondary hole is located on the opposite side of the second secondary hole with respect to the axis of the nozzle in the vertical direction,
  • the ejection direction of the first sub-hole is oriented so as to be opposite to the ejection direction of the second sub-hole.
  • the sub-injection part can inject gas fuel in both the vertical direction.
  • the gas burner according to the present disclosure is A gas burner for burning gas fuel containing hydrogen, A main ejection portion that ejects the gas fuel and includes at least one main hole, and a sub ejection portion that ejects a smaller amount of the gas fuel than the main ejection portion and has at least one sub hole.
  • a nozzle formed at the tip thereof with a sub-jetting part including; a primary air flow path portion that surrounds the periphery of the tip portion of the nozzle and forms a primary air outlet through which the primary air flows out, in a front view viewed along the axial direction of the nozzle; a secondary air flow path portion positioned above or below the primary air outlet in the front view and forming a secondary air outlet through which the secondary air flows,
  • an imaginary line (72) is extended linearly along the vertical direction from the axis of the nozzle, Let r be the distance between a first intersection point (74) where the imaginary line intersects the circumference of the primary air outlet and the axis of the nozzle, and the imaginary line intersects first among the circumferences of the secondary air outlet.
  • d be the distance between the second intersection point (76) and said axis of said nozzle, satisfying 2 ⁇ r ⁇ d,
  • the ejection direction of the at least one main hole is oriented in a direction intersecting with the secondary air outlet.
  • the secondary air outlet is spaced apart from the tip of the nozzle in which the main ejection portion is formed so as to satisfy 2 ⁇ r ⁇ d. It is possible to delay the contact between the gaseous fuel ejected from the main hole and the secondary air flowing out from the secondary air outlet. Therefore, by slowing the mixing of hydrogen and oxygen, it is possible to suppress the temperature rise in the combustion space and suppress the generation of NOx.
  • the gas burner is a rectangular burner whose end surface facing the furnace has a longitudinal direction along the vertical direction.
  • the combustion facility comprises: a furnace (2); and the gas burner according to any one of [1] to [13] above, which is provided in the furnace.

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Abstract

This gas burner (4) for burning a gaseous fuel (F) including hydrogen comprises: a nozzle (20) having a tip portion (26) on which are formed a main injector (28) for injecting the gaseous fuel, the main injector including at least one main hole (32), and an auxiliary injector (30) for injecting a smaller amount of the gaseous fuel than the main injector, the auxiliary injector including at least one auxiliary hole (34); a primary air flow path (22) surrounding the periphery of the tip portion of the nozzle in a front view seen along an axial direction (D1) of the nozzle and forming a primary air outlet port (36) for discharging primary air (A1); and a secondary air flow path (24) positioned above or below the primary air outlet port in the front view and forming a secondary air outlet port (40) for discharging secondary air (A2), wherein, in the front view, an injection direction (D5) of the at least one auxiliary hole is oriented in a direction that intersects the secondary air outlet port, and an injection direction (D4) of the at least one main hole is oriented in a direction that does not intersect the secondary air outlet port.

Description

ガスバーナ、及び燃焼設備Gas burner and combustion equipment
　本開示は、水素を含むガス燃料を燃焼するためのガスバーナ、及び燃焼設備に関する。
　本願は、２０２１年９月３０日に日本国特許庁に出願された特願２０２１－１６０７９４号に基づき優先権を主張し、その内容をここに援用する。 The present disclosure relates to gas burners and combustion equipment for burning gaseous fuels containing hydrogen.
This application claims priority based on Japanese Patent Application No. 2021-160794 filed with the Japan Patent Office on September 30, 2021, the contents of which are incorporated herein.
　ボイラのような燃焼設備には、燃料を燃焼するバーナが設置されており、好適な燃焼状態を実現するために保炎性を高める技術や窒素酸化物（ＮＯｘ）の発生を抑制する技術が知られている。例えば、特許文献１には、ノズルの中心軸線上に配置され、燃料ガスの流通方向の下流側に向かうにつれて拡幅するスプリット形状を有する保炎器を備えるガスバーナが開示されている。 Combustion facilities such as boilers are equipped with burners that burn fuel, and technologies for improving flame stability and suppressing the generation of nitrogen oxides (NOx) are known to achieve optimal combustion conditions. It is For example, Patent Literature 1 discloses a gas burner provided with a split-shaped flame stabilizer that is arranged on the central axis of the nozzle and widens toward the downstream side in the flow direction of the fuel gas.
特開２０１１－１４９６７６号公報JP 2011-149676 A
　ところで、幾つかの燃焼設備では、代表的な温室効果ガスである二酸化炭素の排出量削減を目的として、化石燃料から脱却する取り組み（脱炭素）が進められている。この脱炭素の１つとして、ガスバーナの燃料として水素を含むガス燃料が適用されることがある。水素は、従来からの燃料に含まれる成分（例えば、都市ガスに含まれるメタンやＬＰＧに含まれるプロパン、特許文献１に記載の燃料ガスに含まれている微粉炭）とは大きく異なる特性を有する。しかしながら、特許文献１に記載の技術は、水素の特性を考慮して、保炎性を高める構成やＮＯｘの発生を抑制する構成となっていない。つまり、ガスバーナが水素を含むガス燃料を用いる場合には、ガスバーナを水素の特性が考慮された構成に改善する余地がある。 By the way, in some combustion facilities, efforts to break away from fossil fuels (decarbonization) are underway with the aim of reducing emissions of carbon dioxide, a typical greenhouse gas. As one of the decarbonization methods, a gas fuel containing hydrogen may be applied as a fuel for a gas burner. Hydrogen has characteristics that are significantly different from the components contained in conventional fuels (for example, methane contained in city gas, propane contained in LPG, and pulverized coal contained in the fuel gas described in Patent Document 1). . However, the technique described in Patent Literature 1 does not take the characteristics of hydrogen into consideration and does not provide a configuration that enhances flame stability or suppresses the generation of NOx. In other words, when the gas burner uses gas fuel containing hydrogen, there is room for improving the structure of the gas burner in consideration of the characteristics of hydrogen.
　本開示は、上述の課題に鑑みてなされたものであって、水素を含むガス燃料を用いる場合に好適な燃焼状態を実現することができるガスバーナを提供することを目的とする。 The present disclosure has been made in view of the above problems, and aims to provide a gas burner capable of achieving a suitable combustion state when using gas fuel containing hydrogen.
　上記目的を達成するため、本開示に係るガスバーナは、水素を含むガス燃料を燃焼するためのガスバーナであって、前記ガス燃料を噴出する主噴出部であって少なくとも１つの主孔を含む主噴出部、及び前記主噴出部よりも少量の前記ガス燃料を噴出する副噴出部であって少なくとも１つの副孔を含む副噴出部、が先端部に形成されるノズルと、前記ノズルの軸線方向に沿って視認した正面視において、前記ノズルの前記先端部の周囲を囲むとともに、一次空気が流出する一次空気出口を形成する一次空気流路部と、前記正面視において、前記一次空気出口の上方または下方に位置するとともに、二次空気が流出する二次空気出口を形成する二次空気流路部と、を備え、前記正面視において、前記少なくとも１つの副孔の噴出方向は、前記二次空気出口と交差する方向に配向され、前記少なくとも１つの主孔の噴出方向は、前記二次空気出口と交差しない方向に配向される。 In order to achieve the above object, a gas burner according to the present disclosure is a gas burner for burning gas fuel containing hydrogen, wherein a main ejection part for ejecting the gas fuel includes at least one main hole. and a sub-ejection portion that ejects a smaller amount of the gas fuel than the main ejection portion and includes at least one sub-hole, formed at the tip of the nozzle; A primary air flow path portion that surrounds the periphery of the tip portion of the nozzle and forms a primary air outlet through which the primary air flows out in a front view viewed along the line, and a primary air flow path portion above the primary air outlet or in the front view a secondary air flow path portion positioned below and forming a secondary air outlet through which the secondary air flows, wherein in the front view, the ejection direction of the at least one secondary hole is aligned with the secondary air It is oriented transversely to the outlet, and the jetting direction of said at least one main hole is oriented non- transversely to said secondary air outlet.
　本開示のガスバーナによれば、水素を含むガス燃料を用いる場合に好適な燃焼状態を実現することができる。 According to the gas burner of the present disclosure, it is possible to achieve a favorable combustion state when using gas fuel containing hydrogen.
第１実施形態に係る燃焼設備の構成を概略的に示す図である。BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows roughly the structure of the combustion equipment which concerns on 1st Embodiment. 第１実施形態に係る火炉の内部構成を概略的に示す図である。It is a figure which shows roughly the internal structure of the furnace which concerns on 1st Embodiment. 第１実施形態に係るガスバーナの構成を概略的に示す図である。It is a figure showing roughly composition of a gas burner concerning a 1st embodiment. 第１実施形態に係るガスバーナの内部構成を概略的に示す図である。It is a figure which shows roughly the internal structure of the gas burner which concerns on 1st Embodiment. 第１実施形態に係る主孔の噴出方向を説明するための図である。It is a figure for demonstrating the ejection direction of the main hole which concerns on 1st Embodiment. 第１実施形態に係る副孔の噴出方向を説明するための図である。It is a figure for demonstrating the ejection direction of the subhole which concerns on 1st Embodiment. 第１実施形態に係る保炎器の保炎面を説明するための図である。FIG. 4 is a diagram for explaining a flame stabilizing surface of the flame stabilizer according to the first embodiment; 幾つかの実施形態に係るノズルの先端部の構成を示す図である。[0013] Figure 4 illustrates a nozzle tip configuration according to some embodiments; 第２実施形態に係るノズルの先端部の構成を示す図である。It is a figure which shows the structure of the front-end|tip part of the nozzle which concerns on 2nd Embodiment. 第２実施形態の変形例に係る主孔の形状を示す図である。It is a figure which shows the shape of the main hole which concerns on the modification of 2nd Embodiment. 第３実施形態に係るガスバーナの構成を概略的に示す図である。It is a figure which shows roughly the structure of the gas burner which concerns on 3rd Embodiment. 第３実施形態に係る二次空気出口のレイアウトを説明するための図である。FIG. 11 is a diagram for explaining the layout of secondary air outlets according to the third embodiment; 幾つかの実施形態に係る火炉の内部構成を概略的に示す図である。1 is a diagram schematically showing the internal configuration of a furnace according to some embodiments; FIG. 幾つかの実施形態に係る火炉の内部構成を概略的に示す図である。1 is a diagram schematically showing the internal configuration of a furnace according to some embodiments; FIG. 幾つかの実施形態に係る火炉の内部構成を概略的に示す図である。1 is a diagram schematically showing the internal configuration of a furnace according to some embodiments; FIG.
　以下、本開示の実施の形態によるガスバーナについて、図面に基づいて説明する。かかる実施の形態は、本開示の一態様を示すものであり、この開示を限定するものではなく、本開示の技術的思想の範囲内で任意に変更可能である。 A gas burner according to an embodiment of the present disclosure will be described below based on the drawings. Such an embodiment shows one aspect of the present disclosure, does not limit the present disclosure, and can be arbitrarily changed within the scope of the technical idea of the present disclosure.
　＜第１実施形態＞
　（構成）
　図１は、第１実施形態に係る燃焼設備１の構成を概略的に示す図である。図１に例示するように、燃焼設備１は、火炉２と、火炉２に設けられ、水素を含むガス燃料Ｆを火炉２内で燃焼するためのガスバーナ４と、を備える。燃焼設備１は、例えば、ボイラであって、ガスバーナ４から火炉２内に噴出されたガス燃料Ｆを火炎Ｘを発生させて燃焼させることで高温の排ガスＧを生成し、この高温の排ガスＧから熱を回収することで蒸気を生成する。尚、排ガスＧの熱は、火炉２内に設けられる熱交換器によって回収されてもよいし、火炉２外に設けられる熱交換器によって回収されてもよい。 <First embodiment>
(composition)
FIG. 1 is a diagram schematically showing the configuration of combustion equipment 1 according to the first embodiment. As illustrated in FIG. 1 , the combustion facility 1 includes a furnace 2 and a gas burner 4 provided in the furnace 2 for burning gas fuel F containing hydrogen in the furnace 2 . The combustion equipment 1 is, for example, a boiler, and generates a high-temperature exhaust gas G by burning the gas fuel F ejected from the gas burner 4 into the furnace 2 by generating a flame X, and from this high-temperature exhaust gas G Generates steam by recovering heat. The heat of the exhaust gas G may be recovered by a heat exchanger provided inside the furnace 2 or may be recovered by a heat exchanger provided outside the furnace 2 .
　本開示において、「水素を含むガス燃料Ｆ」には、水素と水素以外の燃料を含むもの（混焼）と、水素のみ（専焼）とがあり、さらに、水素と水素以外の燃料を含むものでも、水素が主たる燃料（水素の体積割合が５０％以上）、水素以外の燃料が主たる燃料（水素の体積割合が５０％未満）に区分できる。「水素を含むガス燃料」とは、これらの場合をすべて含む。 In the present disclosure, "gas fuel F containing hydrogen" includes fuel containing hydrogen and fuel other than hydrogen (mixed combustion) and hydrogen only (single combustion), and further, fuel containing hydrogen and fuel other than hydrogen , hydrogen as the main fuel (50% or more by volume of hydrogen), and fuel other than hydrogen as the main fuel (less than 50% by volume of hydrogen). "Gaseous fuel containing hydrogen" includes all of these cases.
　火炉２の構成について説明する。図２は、第１実施形態に係る火炉２の内部構成を概略的に示す図であって、火炉２を鉛直方向から視た図である。第１実施形態では、火炉２は、鉛直方向に沿って長手方向を有する四角筒形状を有している。そして、図２に例示するように、火炉２にはガスバーナ４から噴出されたガス燃料Ｆを燃焼させるための燃焼空間６が形成されている。この火炉２の燃焼空間６は矩形状を有している。 The configuration of the furnace 2 will be explained. FIG. 2 is a view schematically showing the internal configuration of the furnace 2 according to the first embodiment, and is a view of the furnace 2 viewed from the vertical direction. In the first embodiment, the furnace 2 has a rectangular tubular shape with its longitudinal direction along the vertical direction. As illustrated in FIG. 2, the furnace 2 is formed with a combustion space 6 for burning the gas fuel F ejected from the gas burner 4 . The combustion space 6 of this furnace 2 has a rectangular shape.
　火炉２は、火炉２の内周面７のうち燃焼空間６の矩形状の何れか１つの辺に対応する第１内周面７ａを含む第１炉壁８と、燃焼空間６を挟んで第１炉壁８とは反対側に位置する第２炉壁１０と、第１炉壁８の一端部１６と第２炉壁１０の一端部１８とを接続する第３炉壁１２と、第１炉壁８の他端部１７と第２炉壁１０の他端部１９とを接続する第４炉壁１４と、を含む。第３炉壁１２は、燃焼空間６を挟んで第４炉壁１４とは反対側に位置している。火炉２の燃焼空間６は、第１炉壁８、第２炉壁１０、第３炉壁１２、及び第４炉壁１４によって囲われることで矩形状に形成されている。 The furnace 2 has a first furnace wall 8 including a first inner peripheral surface 7a corresponding to one side of the rectangular combustion space 6 among the inner peripheral surfaces 7 of the furnace 2, and a first furnace wall 8 with the combustion space 6 interposed therebetween. a second furnace wall 10 located on the opposite side of the first furnace wall 8; a third furnace wall 12 connecting one end portion 16 of the first furnace wall 8 and one end portion 18 of the second furnace wall 10; and a fourth furnace wall 14 connecting the other end 17 of the furnace wall 8 and the other end 19 of the second furnace wall 10 . The third furnace wall 12 is located on the opposite side of the combustion space 6 from the fourth furnace wall 14 . A combustion space 6 of the furnace 2 is formed in a rectangular shape by being surrounded by a first furnace wall 8, a second furnace wall 10, a third furnace wall 12, and a fourth furnace wall .
　第１実施形態では、図２に例示するように、火炉２には複数のガスバーナ４が設けられている。複数のガスバーナ４は、第３炉壁１２より第４炉壁１４に近接するように第１炉壁８に設けられる第１ガスバーナ４Ａ（４）と、第４炉壁１４より第３炉壁１２に近接するように第２炉壁１０に設けられる第２ガスバーナ４Ｂ（４）と、第２炉壁１０より第１炉壁８に近接するように第３炉壁１２に設けられる第３ガスバーナ４Ｃ（４）と、第１炉壁８より第２炉壁１０に近接するように第４炉壁１４に設けられる第４ガスバーナ４Ｄ（４）と、を含む。複数のガスバーナ４のそれぞれは、燃焼空間６の矩形状の角部２１にガス燃料Ｆを噴出している。尚、不図示であるが、複数のガスバーナ４は、第１ガスバーナ４Ａに積み上げられる上側ガスバーナをさらに含んでもよい。 In the first embodiment, the furnace 2 is provided with a plurality of gas burners 4, as illustrated in FIG. The plurality of gas burners 4 includes a first gas burner 4A (4) provided on the first furnace wall 8 so as to be closer to the fourth furnace wall 14 than the third furnace wall 12, A second gas burner 4B (4) provided on the second furnace wall 10 so as to be closer to the second furnace wall 10, and a third gas burner 4C provided on the third furnace wall 12 so as to be closer to the first furnace wall 8 than the second furnace wall 10 (4), and a fourth gas burner 4D (4) provided on the fourth furnace wall 14 so as to be closer to the second furnace wall 10 than to the first furnace wall 8. Each of the plurality of gas burners 4 jets gas fuel F to rectangular corners 21 of the combustion space 6 . Although not shown, the plurality of gas burners 4 may further include an upper gas burner stacked on the first gas burner 4A.
　ガスバーナ４は、ガス燃料Ｆを燃焼する。第１実施形態では、図１に例示するように、燃焼設備１は、ガスバーナ４にガス燃料Ｆを供給するガス燃料供給装置１００と、ガスバーナ４に燃焼用空気Ａを供給する空気供給装置１０２と、をさらに含む。そして、ガスバーナ４は、ガス燃料供給装置１００から供給されたガス燃料Ｆに、空気供給装置１０２から供給された燃焼用空気Ａを混合させて火炉２内（燃焼空間６）に噴出し、ガス燃料Ｆを燃焼する。 The gas burner 4 burns the gas fuel F. In the first embodiment, as illustrated in FIG. 1, the combustion facility 1 includes a gas fuel supply device 100 that supplies gas fuel F to the gas burner 4, and an air supply device 102 that supplies combustion air A to the gas burner 4. , further includes. Then, the gas burner 4 mixes the gas fuel F supplied from the gas fuel supply device 100 with the combustion air A supplied from the air supply device 102, and ejects the gas fuel into the furnace 2 (combustion space 6). Burn F.
　ガス燃料供給装置１００は、ガス燃料Ｆが貯蔵されているガスタンク１０４と、ガスタンク１０４とガスバーナ４とを接続し、ガスタンク１０４に貯蔵されているガス燃料Ｆをガスバーナ４に向かって流通可能な燃料供給ライン１０６と、を含む。 The gas fuel supply device 100 connects a gas tank 104 in which gas fuel F is stored, the gas tank 104 and the gas burner 4, and supplies the gas fuel F stored in the gas tank 104 to the gas burner 4 so as to be circulated. lines 106 and .
　空気供給装置１０２は、一端が大気に開放され、他端がガスバーナ４に接続されている空気供給ライン１０８と、空気供給ライン１０８に設けられ、空気供給ライン１０８の一端から取り込まれた空気を燃焼用空気Ａとして火炉２に送風する送風機１１０と、備える。 The air supply device 102 includes an air supply line 108, one end of which is open to the atmosphere and the other end of which is connected to the gas burner 4, and an air supply line 108, which burns air taken in from one end of the air supply line 108. A blower 110 for blowing air A to the furnace 2 is provided.
　ガスバーナ４の構成について具体的に説明する。図３は、第１実施形態に係るガスバーナ４の構成を概略的に示す図であって、ガスバーナ４を火炉２の燃焼空間６側から視た図（正面図）である。図４は、第１実施形態に係るガスバーナ４の内部構成を概略的に示す図であって、ガスバーナ４を後述する左右方向Ｄ３に沿って視た図である。 The configuration of the gas burner 4 will be specifically described. FIG. 3 is a diagram schematically showing the configuration of the gas burner 4 according to the first embodiment, and is a diagram (front view) of the gas burner 4 as seen from the combustion space 6 side of the furnace 2. FIG. FIG. 4 is a view schematically showing the internal configuration of the gas burner 4 according to the first embodiment, and is a view of the gas burner 4 as seen along a left-right direction D3, which will be described later.
　以下、ガスバーナ４のノズル２０の軸線Ｏが延びる方向をノズル２０の軸線方向Ｄ１とする。ガスバーナ４を火炉２の燃焼空間６側から視た場合に、鉛直方向Ｄ２と直交する方向を左右方向Ｄ３とする。 Hereinafter, the direction in which the axis O of the nozzle 20 of the gas burner 4 extends is defined as the axial direction D1 of the nozzle 20. When the gas burner 4 is viewed from the side of the combustion space 6 of the furnace 2, the direction orthogonal to the vertical direction D2 is defined as the left-right direction D3.
　図３及び図４に例示するように、ガスバーナ４は、ノズル２０と、一次空気流路部２２と、二次空気流路部２４と、保炎器５０と、を備える。第１実施形態では、図３に例示するように、ガスバーナ４は、火炉２の燃焼空間６に面する前面５の形状が鉛直方向Ｄ２に沿って長手方向を有する矩形状の角型バーナである。 As illustrated in FIGS. 3 and 4, the gas burner 4 includes a nozzle 20, a primary air flow path portion 22, a secondary air flow path portion 24, and a flame stabilizer 50. In the first embodiment, as illustrated in FIG. 3, the gas burner 4 is a rectangular burner whose front surface 5 facing the combustion space 6 of the furnace 2 has a longitudinal direction along the vertical direction D2. .
　ノズル２０は、ガス燃料Ｆが流通可能であるように、例えば、軸線Ｏを中心とする円筒形状を有する。そして、図４に例示するように、ノズル２０は、ガス燃料供給装置１００から供給されるガス燃料Ｆを火炉２の燃焼空間６に噴出する。具体的には、図３に例示するように、ノズル２０の先端部２６（バーナチップ）には、主噴出部２８と副噴出部３０とが形成されている。主噴出部２８はガス燃料供給装置１００から供給されたガス燃料Ｆの一部を火炉２の燃焼空間６に噴出し、副噴出部３０はガス燃料供給装置１００から供給されたガス燃料Ｆの残部を火炉２の燃焼空間６に噴出する。副噴出部３０は、主噴出部２８よりも少量のガス燃料Ｆを噴出するように構成されている。つまり、主噴出部２８から噴出されるガス燃料Ｆの一部の量は、副噴出部３０から噴出されるガス燃料Ｆの残部の量より多い。 The nozzle 20 has, for example, a cylindrical shape centered on the axis O so that the gas fuel F can flow. Then, as illustrated in FIG. 4 , the nozzle 20 ejects the gas fuel F supplied from the gas fuel supply device 100 into the combustion space 6 of the furnace 2 . Specifically, as illustrated in FIG. 3 , a main ejection portion 28 and a sub-ejection portion 30 are formed at the tip portion 26 (burner tip) of the nozzle 20 . The main ejection part 28 ejects part of the gas fuel F supplied from the gas fuel supply device 100 into the combustion space 6 of the furnace 2, and the sub ejection part 30 is the remaining part of the gas fuel F supplied from the gas fuel supply device 100. is ejected into the combustion space 6 of the furnace 2. The secondary ejection part 30 is configured to eject a smaller amount of gas fuel F than the main ejection part 28 . That is, the amount of a portion of the gas fuel F ejected from the main ejection portion 28 is greater than the remaining amount of the gas fuel F ejected from the sub ejection portion 30 .
　第１実施形態では、図３に例示するように、主噴出部２８は２つの主孔３２を含む。第１主孔３２Ａ（３２）は、左右方向Ｄ３において、ノズル２０の軸線Ｏを挟んで第２主孔３２Ｂ（３２）とは反対側に位置している。第１主孔３２Ａはノズル２０の軸線Ｏより左側に位置し、第２主孔３２Ｂはノズル２０の軸線Ｏより右側に位置している。 In the first embodiment, the main ejection portion 28 includes two main holes 32, as illustrated in FIG. The first main hole 32A (32) is located on the opposite side of the second main hole 32B (32) across the axis O of the nozzle 20 in the left-right direction D3. The first main hole 32A is located on the left side of the axis O of the nozzle 20, and the second main hole 32B is located on the right side of the axis O of the nozzle 20. As shown in FIG.
　第１実施形態では、図３に例示するように、副噴出部３０は２つの副孔３４を含む。第１副孔３４Ａ（３４）は、鉛直方向Ｄ２において、ノズル２０の軸線Ｏを挟んで第２副孔３４Ｂ（３４）とは反対側に位置している。第１副孔３４Ａはノズル２０の軸線Ｏより上側に位置し、第２副孔３４Ｂはノズル２０の軸線Ｏより下側に位置している。 In the first embodiment, as illustrated in FIG. 3, the sub ejection portion 30 includes two sub holes 34. The first secondary hole 34A (34) is located on the opposite side of the axis O of the nozzle 20 from the second secondary hole 34B (34) in the vertical direction D2. The first secondary hole 34A is located above the axis O of the nozzle 20, and the second secondary hole 34B is located below the axis O of the nozzle 20. As shown in FIG.
　第１主孔３２Ａ及び第２主孔３２Ｂのそれぞれは、鉛直方向Ｄ２において、第１副孔３４Ａと第２副孔３４Ｂとの間に位置している。第１副孔３４Ａ及び第２副孔３４Ｂのそれぞれは、左右方向Ｄ３において、第１主孔３２Ａと第２主孔３２Ｂとの間に位置している。 Each of the first main hole 32A and the second main hole 32B is located between the first secondary hole 34A and the second secondary hole 34B in the vertical direction D2. Each of the first sub-hole 34A and the second sub-hole 34B is located between the first main hole 32A and the second main hole 32B in the left-right direction D3.
　第１主孔３２Ａは、第１副孔３４Ａ及び第２副孔３４Ｂのそれぞれより大径である。第２主孔３２Ｂは、第１副孔３４Ａ及び第２副孔３４Ｂのそれぞれより大径である。第１主孔３２Ａと第２主孔３２Ｂとは同径である。第１副孔３４Ａと第２副孔３４Ｂとは同径である。このように、主孔３２の開口面積の合計は副孔３４の開口面積の合計よりも大きく、主噴出部２８は副噴出部３０より多くのガス燃料Ｆを噴出できるようになっている。 The first main hole 32A has a larger diameter than each of the first secondary hole 34A and the second secondary hole 34B. The second main hole 32B has a larger diameter than each of the first secondary hole 34A and the second secondary hole 34B. The first main hole 32A and the second main hole 32B have the same diameter. The first secondary hole 34A and the second secondary hole 34B have the same diameter. In this way, the total opening area of the main holes 32 is larger than the total opening area of the sub-holes 34, so that the main jetting portion 28 can jet more fuel gas F than the sub-jetting portion 30 can.
　一次空気流路部２２は、図３に例示するように、ノズル２０の軸線方向Ｄ１に沿って視認した正面視（以下、「正面視」とする）において、ノズル２０の先端部２６の周囲を囲む。そして、この一次空気流路部２２は、空気供給装置１０２から供給される燃焼用空気Ａを一次空気Ａ１として流出する一次空気出口３６を形成する。 As illustrated in FIG. 3 , the primary air flow path portion 22 extends around the tip portion 26 of the nozzle 20 in a front view (hereinafter referred to as “front view”) viewed along the axial direction D1 of the nozzle 20. surround. The primary air flow path portion 22 forms a primary air outlet 36 through which the combustion air A supplied from the air supply device 102 flows out as the primary air A1.
　第１実施形態では、図４に例示するように、一次空気流路部２２は、空気供給装置１０２から供給される一次空気Ａ１が流通する一次空気流路３８を含む。一次空気流路部２２（スリーブ）は、円筒形状を有しており、ノズル２０の軸線方向Ｄ１に沿って延びている。一次空気流路部２２の内径はノズル２０の外径より大きく、ノズル２０が一次空気流路部２２内に配置されている。つまり、一次空気流路部２２は、一次空気流路部２２の内壁面とノズル２０の外壁面との間に一次空気Ａ１が流通する一次空気流路３８を含む。別の言い方をすると、一次空気流路３８は、ノズル２０の外周に形成されている。 In the first embodiment, as illustrated in FIG. 4, the primary air flow path section 22 includes a primary air flow path 38 through which the primary air A1 supplied from the air supply device 102 flows. The primary air flow path portion 22 (sleeve) has a cylindrical shape and extends along the axial direction D1 of the nozzle 20 . The inner diameter of the primary air flow path portion 22 is larger than the outer diameter of the nozzle 20 , and the nozzle 20 is arranged within the primary air flow path portion 22 . That is, the primary air channel portion 22 includes the primary air channel 38 through which the primary air A1 flows between the inner wall surface of the primary air channel portion 22 and the outer wall surface of the nozzle 20 . Stated another way, the primary air flow path 38 is formed around the outer circumference of the nozzle 20 .
　二次空気流路部２４は、図３に例示するように、正面視において、一次空気出口３６の上方又は下方に位置するとともに、一次空気Ａ１より遅れてガス燃料Ｆに接触させる二次空気Ａ２が流出する二次空気出口４０を形成する。二次空気Ａ２は、空気供給装置１０２から供給される燃焼用空気Ａであってもよいし、火炉２から流出された排ガスＧの一部を火炉２に循環させた循環ガスＥｇであってもよい。あるいは、二次空気Ａ２は、燃焼用空気Ａに循環ガスＥｇを混合させたものであってもよい。 As illustrated in FIG. 3, the secondary air flow path portion 24 is positioned above or below the primary air outlet 36 in a front view, and the secondary air A2 is brought into contact with the gas fuel F later than the primary air A1. forms a secondary air outlet 40 through which . The secondary air A2 may be the combustion air A supplied from the air supply device 102, or the circulating gas Eg obtained by circulating part of the exhaust gas G discharged from the furnace 2 to the furnace 2. good. Alternatively, the secondary air A2 may be a mixture of the combustion air A and the circulating gas Eg.
　第１実施形態では、二次空気流路部２４は、上側二次空気流路部２４Ａ（２４）と下側二次空気流路部２４Ｂ（２４）とを含む。上側二次空気流路部２４Ａの二次空気出口４０Ａ（４０）は、一次空気出口３６より上方に位置している。左右方向Ｄ３において、一次空気出口３６と上側二次空気流路部２４Ａの二次空気出口４０Ａとは少なくとも一部が互いに重複している。下側二次空気流路部２４Ｂの二次空気出口４０Ｂ（４０）は、一次空気出口３６より下方に位置している。左右方向Ｄ３において、一次空気出口３６と下側二次空気流路部２４Ｂの二次空気出口４０Ｂとは少なくとも一部が互いに重複している。上側二次空気流路部２４Ａの二次空気出口４０Ａは、一次空気出口３６を挟んで下側二次空気流路部２４Ｂの二次空気出口４０Ｂとは反対側に位置している。 In the first embodiment, the secondary air channel portion 24 includes an upper secondary air channel portion 24A (24) and a lower secondary air channel portion 24B (24). A secondary air outlet 40</b>A ( 40 ) of the upper secondary air flow path portion 24</b>A is located above the primary air outlet 36 . At least a portion of the primary air outlet 36 and the secondary air outlet 40A of the upper secondary air flow path portion 24A overlap each other in the left-right direction D3. A secondary air outlet 40B (40) of the lower secondary air flow path portion 24B is located below the primary air outlet 36. As shown in FIG. At least a portion of the primary air outlet 36 and the secondary air outlet 40B of the lower secondary air flow path portion 24B overlap each other in the left-right direction D3. The secondary air outlet 40A of the upper secondary air channel portion 24A is located on the opposite side of the primary air outlet 36 from the secondary air outlet 40B of the lower secondary air channel portion 24B.
　第１実施形態では、二次空気出口４０は、内側出口４２と内側出口４２より一次空気出口３６から離れて位置する外側出口４４とを含む。つまり、上側二次空気流路部２４Ａの二次空気出口４０Ａは、内側出口４２Ａ（４２）と外側出口４４Ａ（４４）とを含む。下側二次空気流路部２４Ｂの二次空気出口４０Ｂは、内側出口４２Ｂ（４２）と外側出口４４Ｂ（４４）とを含む。そして、正面視において、上方から順に、二次空気出口４０Ａの外側出口４４Ａ、二次空気出口４０Ａの内側出口４２Ａ、一次空気出口３６、二次空気出口４０Ｂの内側出口４２Ｂ、及び二次空気出口４０Ｂの外側出口４４Ｂが並んでいる。 In the first embodiment, the secondary air outlet 40 includes an inner outlet 42 and an outer outlet 44 located further from the primary air outlet 36 than the inner outlet 42 . That is, the secondary air outlet 40A of the upper secondary air flow path portion 24A includes an inner outlet 42A (42) and an outer outlet 44A (44). The secondary air outlet 40B of the lower secondary air flow path portion 24B includes an inner outlet 42B (42) and an outer outlet 44B (44). In a front view, from above, the outer outlet 44A of the secondary air outlet 40A, the inner outlet 42A of the secondary air outlet 40A, the primary air outlet 36, the inner outlet 42B of the secondary air outlet 40B, and the secondary air outlet 40B are aligned with outer exits 44B.
　外側出口４４は、二次空気Ａ２が流出するように構成される。第１実施形態では、図４に例示するように、外側出口４４は空気供給装置１０２から供給される燃焼用空気Ａを二次空気Ａ２として流出する。尚、第１実施形態では、正面視において、外側出口４４は矩形状を有しているが、本開示はこの形態に限定されない。 The outer outlet 44 is configured so that the secondary air A2 flows out. In the first embodiment, as illustrated in FIG. 4, the combustion air A supplied from the air supply device 102 flows out from the outer outlet 44 as the secondary air A2. In addition, in the first embodiment, the outer outlet 44 has a rectangular shape when viewed from the front, but the present disclosure is not limited to this shape.
　内側出口４２は、外側出口４４から流出される二次空気Ａ２より酸素濃度の低い低酸素二次空気Ａ３が流出するように構成される。第１実施形態では、図４に例示するように、低酸素二次空気Ａ３は、火炉２から流出された排ガスＧの一部を火炉２に循環させた循環ガスＥｇである。尚、第１実施形態では、正面視において、内側出口４２は矩形状を有しているが、本開示はこの形態に限定されない。 The inner outlet 42 is configured so that low-oxygen secondary air A3 having a lower oxygen concentration than the secondary air A2 that flows out from the outer outlet 44 flows out. In the first embodiment, as illustrated in FIG. 4 , the low-oxygen secondary air A3 is a circulating gas Eg obtained by circulating part of the exhaust gas G flowing out of the furnace 2 to the furnace 2 . In addition, in the first embodiment, the inner outlet 42 has a rectangular shape when viewed from the front, but the present disclosure is not limited to this shape.
　図３に例示するように、正面視において、主孔３２の噴出方向Ｄ４は、二次空気出口４０と交差しない方向に配向される。さらに、正面視において、副孔３４の噴出方向Ｄ５は、二次空気出口４０と交差する方向に配向される。第１実施形態では、第１主孔３２Ａの噴出方向Ｄ４は左方であり、第２主孔３２Ｂの噴出方向Ｄ４は右方である。第１副孔３４Ａの噴出方向Ｄ５は上方であり、第２副孔３４Ｂの噴出方向Ｄ５は下方である。 As illustrated in FIG. 3, the ejection direction D4 of the main hole 32 is oriented in a direction that does not intersect the secondary air outlet 40 when viewed from the front. Furthermore, when viewed from the front, the ejection direction D5 of the secondary holes 34 is oriented in a direction intersecting with the secondary air outlet 40 . In the first embodiment, the ejection direction D4 of the first main hole 32A is leftward, and the ejection direction D4 of the second main hole 32B is rightward. The ejection direction D5 of the first secondary hole 34A is upward, and the ejection direction D5 of the second secondary hole 34B is downward.
　図５は、第１実施形態に係る主孔３２の噴出方向Ｄ４を説明するための図であって、ノズル２０の先端部２６を鉛直方向Ｄ２に沿って視た図である。図６は、第１実施形態に係る副孔３４の噴出方向Ｄ５を説明するための図であって、ノズル２０の先端部２６を左右方向Ｄ３に沿って視た図である。 FIG. 5 is a diagram for explaining the ejection direction D4 of the main hole 32 according to the first embodiment, and is a diagram of the tip portion 26 of the nozzle 20 viewed along the vertical direction D2. FIG. 6 is a diagram for explaining the ejection direction D5 of the secondary hole 34 according to the first embodiment, and is a diagram of the tip portion 26 of the nozzle 20 viewed along the left-right direction D3.
　図５に例示するように、第１実施形態では、ノズル２０の先端部２６は、左方又は右方に面する平らな第１端面３７を含む。第１端面３７は、ノズル２０の先端部２６の軸線方向Ｄ１の最も一方側（燃焼空間６側）の先端面４１と側面４３とを接続している。主孔３２はこの第１端面３７に形成されており、主孔３２の噴出方向Ｄ４はこの第１端面３７と直交する方向である。そして、主孔３２の噴出方向Ｄ４とノズル２０の軸線方向Ｄ１とによって形成される角度をθ１とする。 As illustrated in FIG. 5, in the first embodiment, the tip 26 of the nozzle 20 includes a flat first end face 37 facing left or right. The first end face 37 connects the tip face 41 on the farthest one side (the combustion space 6 side) of the tip portion 26 of the nozzle 20 in the axial direction D<b>1 and the side face 43 . The main hole 32 is formed in this first end face 37 , and the ejection direction D4 of the main hole 32 is a direction perpendicular to this first end face 37 . The angle formed by the ejection direction D4 of the main hole 32 and the axial direction D1 of the nozzle 20 is defined as θ1.
　図６に例示するように、第１実施形態では、ノズル２０の先端部２６は上方又は下方に面する平らな第２端面３９を含む。第２端面３９は、ノズル２０の先端部２６の先端面４１と側面４３とを接続している。副孔３４はこの第２端面３９に形成されており、副孔３４の噴出方向Ｄ５はこの第２端面３９と直交する方向である。そして、副孔３４の噴出方向Ｄ５とノズル２０の軸線方向Ｄ１とによって形成される角度をθ２とする。第１実施形態では、θ１＜θ２を満たす。 As illustrated in FIG. 6, in the first embodiment, the tip 26 of the nozzle 20 includes a flat second end surface 39 facing upwards or downwards. The second end surface 39 connects the tip surface 41 and the side surface 43 of the tip portion 26 of the nozzle 20 . The secondary hole 34 is formed in this second end face 39 , and the ejection direction D<b>5 of the secondary hole 34 is perpendicular to this second end face 39 . The angle formed by the ejection direction D5 of the secondary hole 34 and the axial direction D1 of the nozzle 20 is θ2. In the first embodiment, θ1<θ2 is satisfied.
　保炎器５０は、図４に例示するように、ノズル２０の先端部２６に設けられ、一次空気出口３６に向かうにつれてノズル２０の軸線Ｏから離間する保炎面５２を有する。第１実施形態では、保炎器５０は、ノズル２０の先端部２６からノズル２０の軸線Ｏを中心とする径方向の外側に向かって延びる複数の翼５４を含む。複数の翼５４は、ノズル２０の軸線Ｏを中心とする周方向に沿って並んで配置される。例えば、１５個の翼５４が、周方向に沿って２４度の間隔で配置される。 The flame stabilizer 50 is provided at the tip 26 of the nozzle 20 and has a flame stabilization surface 52 that separates from the axis O of the nozzle 20 toward the primary air outlet 36, as illustrated in FIG. In the first embodiment, the flame stabilizer 50 includes a plurality of vanes 54 extending radially outward from the tip 26 of the nozzle 20 about the axis O of the nozzle 20 . The plurality of blades 54 are arranged side by side along the circumferential direction around the axis O of the nozzle 20 . For example, 15 blades 54 are arranged at intervals of 24 degrees along the circumferential direction.
　尚、第１実施形態では、保炎器５０は、複数の翼５４を含む羽根式の保炎器（いわゆる、スワラ－と呼ばれる）であったが、本開示はこの形態に限定されない。幾つかの実施形態では、保炎器５０は、ノズル２０の先端部２６を囲うプレート部を含むお皿式の保炎器（いわゆるディフューザと呼ばれる）である。尚、プレート部にはノズル２０の先端部２６が嵌め込まれる孔が形成されている。保炎器５０がプレート部を含む場合、保炎器５０の保炎面５２は、プレート部のノズル２０の軸線方向Ｄ１の一方側（燃焼空間６側）の面である。 In the first embodiment, the flame stabilizer 50 is a vane-type flame stabilizer (so-called swirler) including a plurality of blades 54, but the present disclosure is not limited to this form. In some embodiments, the flame stabilizer 50 is a dish-type flame stabilizer (so-called diffuser) that includes a plate portion surrounding the tip 26 of the nozzle 20 . A hole into which the tip portion 26 of the nozzle 20 is fitted is formed in the plate portion. When the flame stabilizer 50 includes a plate portion, the flame stabilization surface 52 of the flame stabilizer 50 is the surface of the plate portion on one side (combustion space 6 side) of the nozzle 20 in the axial direction D1.
　図７は、第１実施形態に係る保炎器５０の保炎面５２を説明するための図である。第１実施形態では、保炎面５２は、ノズル２０の軸線方向Ｄ１の一方側（燃焼空間６側）に面する翼５４の後縁５３である。翼５４の後縁５３とノズル２０の軸線方向Ｄ１とによって形成される角度をθ３とすると、θ２≦θ３を満たす。幾つかの実施形態では、翼５４の後縁５３とノズル２０の先端部２６とが接触する接点をＰとすると、接点Ｐを通過する接線５９とノズル２０の軸線Ｏとによって形成される角度θ３１は、θ２≦θ３１を満たす。 FIG. 7 is a diagram for explaining the flame stabilization surface 52 of the flame stabilizer 50 according to the first embodiment. In the first embodiment, the flame stabilizing surface 52 is the trailing edge 53 of the blade 54 facing one side (the combustion space 6 side) of the nozzle 20 in the axial direction D1. Assuming that the angle formed by the trailing edge 53 of the blade 54 and the axial direction D1 of the nozzle 20 is θ3, θ2≦θ3 is satisfied. In some embodiments, the angle θ 31 formed by the tangent line 59 passing through the contact point P and the axis O of the nozzle 20 is defined as P being the point of contact between the trailing edge 53 of the blade 54 and the tip 26 of the nozzle 20 . satisfies θ2≦θ31.
　（作用・効果）
　第１実施形態に係るガスバーナ４の作用・効果について説明する。水素は従来からのガス燃料に含まれる成分と比較して燃焼速度が大きい。このため、ガス燃料Ｆに水素が含まれる場合、ガスバーナ４の保炎のために用いられるガス燃料Ｆの量を少なくすることができる。一方で、水素と酸素との混合が速やかに行われるので、ガス燃料Ｆが燃焼される燃焼空間６の温度を速やかに高くし、窒素酸化物（ＮＯｘ）の発生を促進してしまう。 (action/effect)
Actions and effects of the gas burner 4 according to the first embodiment will be described. Hydrogen has a higher burning velocity than the components contained in conventional gas fuels. Therefore, when the gas fuel F contains hydrogen, the amount of the gas fuel F used for stabilizing the flame of the gas burner 4 can be reduced. On the other hand, since the hydrogen and oxygen are rapidly mixed, the temperature of the combustion space 6 where the gas fuel F is burned is quickly increased, promoting the generation of nitrogen oxides (NOx).
　これに対して、第１実施形態によれば、図３に例示したように、正面視において、副孔３４の噴出方向Ｄ５は、二次空気出口４０と交差する方向に配向される。このため、副孔３４から噴出される少量のガス燃料Ｆを、二次空気出口４０から流出する二次空気Ａ２や低酸素二次空気Ａ３と速やかに接触させて、保炎性を高めることができる。つまり、少量のガス燃料Ｆで保炎性を確保することができる。 On the other hand, according to the first embodiment, as illustrated in FIG. 3, the ejection direction D5 of the secondary hole 34 is oriented in a direction that intersects the secondary air outlet 40 when viewed from the front. Therefore, the small amount of gas fuel F ejected from the secondary hole 34 is quickly brought into contact with the secondary air A2 or the low-oxygen secondary air A3 flowing out from the secondary air outlet 40, thereby improving flame stability. can. In other words, flame stability can be ensured with a small amount of gas fuel F.
　さらに、図３に例示したように、正面視において、主孔３２の噴出方向Ｄ４は、二次空気出口４０と交差しない方向に配向される。このため、主孔３２から噴出される大量のガス燃料Ｆは、副孔３４から噴出されるガス燃料Ｆよりも遅れて、二次空気出口４０から流出する二次空気Ａ２や低酸素二次空気Ａ３と接触する。つまり、主孔３２から噴出されるガス燃料Ｆは、ノズル２０の先端部２６から軸線方向Ｄ１の一方側（燃焼空間６の奥行側）に離間した比較的酸素濃度の低い領域に流れ込む。このため、水素と酸素との混合を緩やかにするとともに、緩慢燃焼の促進が行われて、燃焼空間６の昇温を抑制し、ＮＯｘの発生を抑制することができる。よって、水素を含むガス燃料を用いる場合に好適な燃焼状態（保炎性の確保とＮＯｘの発生の抑制）を実現することができる。 Furthermore, as illustrated in FIG. 3, the ejection direction D4 of the main hole 32 is oriented in a direction that does not cross the secondary air outlet 40 when viewed from the front. Therefore, a large amount of the gas fuel F jetted from the main hole 32 is delayed from the gas fuel F jetted from the secondary hole 34, and the secondary air A2 or the low-oxygen secondary air flowing out from the secondary air outlet 40 is discharged. Make contact with A3. That is, the gaseous fuel F ejected from the main hole 32 flows into a region having a relatively low oxygen concentration spaced apart from the tip portion 26 of the nozzle 20 to one side in the axial direction D1 (the depth side of the combustion space 6). Therefore, the mixture of hydrogen and oxygen is moderated, slow combustion is promoted, temperature rise in the combustion space 6 is suppressed, and the generation of NOx can be suppressed. Therefore, it is possible to achieve a favorable combustion state (ensure flame stabilization and suppress NOx generation) when using a gas fuel containing hydrogen.
　第１実施形態によれば、内側出口４２からは低酸素二次空気Ａ３が流出され、外側出口４４からは二次空気Ａ２が流出される。このため、外側出口４４から流出する二次空気Ａ２に先行して内側出口４２から流出する低酸素二次空気Ａ３を、主孔３２から噴出されるガス燃料Ｆに接触させる。このため、水素と酸素との混合をさらに緩やかにし、燃焼空間６の昇温をさらに抑制することができる。 According to the first embodiment, the low-oxygen secondary air A3 is discharged from the inner outlet 42, and the secondary air A2 is discharged from the outer outlet 44. Therefore, the low-oxygen secondary air A3 flowing out from the inner outlet 42 prior to the secondary air A2 flowing out from the outer outlet 44 is brought into contact with the gas fuel F ejected from the main hole 32 . Therefore, the mixture of hydrogen and oxygen can be made more gentle, and the temperature rise in the combustion space 6 can be further suppressed.
　第１実施形態によれば、第１主孔３２Ａの噴出方向Ｄ４は左方であり、第２主孔３２Ｂの噴出方向Ｄ４は右方である。このため、ノズル２０（主噴出部２８）は、燃焼空間６に左右方向Ｄ３に幅広くガス燃料Ｆを噴出することができる。 According to the first embodiment, the ejection direction D4 of the first main hole 32A is leftward, and the ejection direction D4 of the second main hole 32B is rightward. Therefore, the nozzle 20 (main ejection portion 28) can eject the gas fuel F widely into the combustion space 6 in the left-right direction D3.
　第１実施形態によれば、第１副孔３４Ａの噴出方向Ｄ５は上方であり、第２副孔３４Ｂの噴出方向Ｄ５は下方である。このため、ノズル２０（副噴出部３０）は、燃焼空間６に鉛直方向Ｄ２に幅広くガス燃料Ｆを噴出することができる。 According to the first embodiment, the ejection direction D5 of the first secondary hole 34A is upward, and the ejection direction D5 of the second secondary hole 34B is downward. Therefore, the nozzle 20 (sub-injection portion 30) can widely inject the gas fuel F into the combustion space 6 in the vertical direction D2.
　第１実施形態によれば、θ１＜θ２を満たすので、副孔３４から噴出される少量のガス燃料Ｆと二次空気出口４０から流出する二次空気Ａ２や低酸素二次空気Ａ３との接触を速めつつ、主孔３２から噴出される大量のガス燃料Ｆと二次空気出口４０から流出する二次空気Ａ２や低酸素二次空気Ａ３との接触を遅らせることができる。 According to the first embodiment, since θ1<θ2 is satisfied, contact between a small amount of gaseous fuel F ejected from the secondary hole 34 and the secondary air A2 or low-oxygen secondary air A3 flowing out from the secondary air outlet 40 , the contact between a large amount of gaseous fuel F ejected from the main hole 32 and the secondary air A2 or low-oxygen secondary air A3 flowing out from the secondary air outlet 40 can be delayed.
　幾つかの実施形態では、θ１＜θ２、及び１５度＜θ１＜４５度を満たす。θ１が４５度を超えると、軸線方向Ｄ１の一方側に噴出するガス燃料Ｆの運動量が減少し、燃焼空間６の奥行側へのガス燃料Ｆの供給が不十分になる場合がある。この場合、燃焼空間６内において局所的な発熱率の変動が発生し、燃焼振動が発生しやすくなる。つまり、燃焼空間６の圧力変動による燃焼振動のポテンシャルが大きくなる。また、θ１が１５度未満になると、長炎化が過剰となり熱吸収特性に影響を与える。このため、１５度＜θ１＜４５度を満たすことで、燃焼振動を抑制できると共に、適度な長炎化による緩慢燃焼で燃焼空間６の昇温を抑制することができる。 In some embodiments, θ1<θ2 and 15 degrees<θ1<45 degrees are satisfied. If θ1 exceeds 45 degrees, the momentum of the gas fuel F ejected to one side in the axial direction D1 decreases, and the supply of the gas fuel F to the depth side of the combustion space 6 may become insufficient. In this case, local variations in the heat release rate occur within the combustion space 6, and combustion oscillation is more likely to occur. That is, the potential for combustion oscillation due to pressure fluctuations in the combustion space 6 increases. Further, when θ1 is less than 15 degrees, the flame becomes excessively long, which affects the heat absorption characteristics. Therefore, by satisfying 15°<θ1<45°, it is possible to suppress the combustion oscillation, and to suppress the temperature rise of the combustion space 6 by slow combustion due to moderate lengthening of the flame.
　幾つかの実施形態では、θ１＜θ２、及び３５度＜θ２＜５５度を満たす。θ２が５５度を超えると、保炎器５０近傍での保炎性が強くなり過ぎるため、保炎器５０の焼損ポテンシャルが大きくなると共に、ＮＯｘの発生を促進させる虞がある。また、θ２が３５度未満であると、保炎器５０による保炎効果が弱くなり、振動ポテンシャルが上昇する。３５度＜θ２＜５５度を満たすことで、燃焼振動、保炎器５０の損傷、及びＮＯｘの発生をバランスよく抑制することができる。 In some embodiments, θ1<θ2 and 35 degrees<θ2<55 degrees are satisfied. If θ2 exceeds 55 degrees, the flame stabilizing properties in the vicinity of the flame stabilizer 50 become too strong, which may increase the burnout potential of the flame stabilizer 50 and accelerate the generation of NOx. Further, when θ2 is less than 35 degrees, the flame stabilization effect of the flame stabilizer 50 is weakened and the vibration potential is increased. By satisfying 35 degrees<θ2<55 degrees, combustion oscillation, damage to the flame stabilizer 50, and generation of NOx can be suppressed in a well-balanced manner.
　第１実施形態によれば、θ２≦θ３を満たすので、副孔３４から噴出されるガス燃料Ｆと一次空気Ａ１との接触によって発生する火炎Ｘによる保炎器５０の損傷を抑制することができる。 According to the first embodiment, since θ2≦θ3 is satisfied, it is possible to suppress damage to the flame stabilizer 50 due to the flame X generated by the contact between the gas fuel F ejected from the secondary hole 34 and the primary air A1. .
　ところで、第１実施形態では、ノズル２０の先端部２６には２つの主孔３２と２つの副孔３４とが形成されていたが、主噴出部２８が副噴出部３０より多くのガス燃料Ｆを噴出可能であれば、本開示はこの形態に限定されない。幾つかの実施形態では、ノズル２０の先端部２６には、１つ又は３つ以上の主孔３２が形成される。幾つかの実施形態では、ノズル２０の先端部２６には、１つ又は３つ以上の副孔３４が形成される。 By the way, in the first embodiment, two main holes 32 and two sub-holes 34 were formed in the tip portion 26 of the nozzle 20. can be ejected, the present disclosure is not limited to this form. In some embodiments, the tip 26 of the nozzle 20 is formed with one or more primary holes 32 . In some embodiments, tip 26 of nozzle 20 is formed with one or more secondary holes 34 .
　図８は、幾つかの実施形態に係るノズル２０の先端部２６の構成を示す図である。図８に例示する形態では、主噴出部２８は、副孔３４の数より多い複数の主孔３２を含む。この場合、主孔３２が副孔３４よりも小径、あるいは副孔３４と同径であったとしても、主噴出部２８は副噴出部３０より多くのガス燃料Ｆを噴出できる。 FIG. 8 is a diagram showing the configuration of the tip portion 26 of the nozzle 20 according to some embodiments. In the form illustrated in FIG. 8 , the primary ejection section 28 includes a plurality of primary holes 32 that are greater in number than the secondary holes 34 . In this case, even if the main hole 32 is smaller in diameter than the secondary hole 34 or has the same diameter as the secondary hole 34 , the main ejection portion 28 can eject more gas fuel F than the secondary ejection portion 30 .
　＜第２実施形態＞
　本開示の第２実施形態に係るガスバーナ４について説明する。第２実施形態は、第１実施形態に係る主孔３２の形状を限定したものである。第２実施形態において、第１実施形態の構成要件と同じものは同じ参照符号を付し、その詳細な説明は省略する。 <Second embodiment>
A gas burner 4 according to a second embodiment of the present disclosure will be described. 2nd Embodiment limits the shape of the main hole 32 which concerns on 1st Embodiment. In the second embodiment, the same reference numerals are given to the same components as those of the first embodiment, and detailed description thereof will be omitted.
　図９は、第２実施形態に係るノズル２０の先端部２６の構成を示す図である。第２実施形態では、図９に例示するように、正面視において、主孔３２は鉛直方向Ｄ２に沿って長手方向を有する楕円形状を有している。そして、主孔３２の長軸（長手方向）の長さをＬ、主孔３２の短軸（短手方向）の長さをＷとすると、２×Ｗ＜Ｌを満たす。尚、説明を簡略化するため、第１主孔３２Ａと第２主孔３２Ｂとは、互いに同一形状、且つ同一面積であるとする。 FIG. 9 is a diagram showing the configuration of the tip portion 26 of the nozzle 20 according to the second embodiment. In the second embodiment, as illustrated in FIG. 9, the main hole 32 has an elliptical shape with its longitudinal direction extending along the vertical direction D2 when viewed from the front. When the length of the major axis (longitudinal direction) of the main hole 32 is L, and the length of the minor axis (lateral direction) of the main hole 32 is W, 2×W<L is satisfied. In order to simplify the explanation, it is assumed that the first main hole 32A and the second main hole 32B have the same shape and the same area.
　第２実施形態によれば、一次空気Ａ１又は二次空気Ａ２が主孔３２から噴出されるガス燃料Ｆよりノズル２０の径方向の内側の領域Ｒ（図９参照）に流れ込むことを抑制することができる。つまり、水素と酸素との混合を遅らせ、ＮＯｘの発生をさらに抑制することができる。 According to the second embodiment, the primary air A1 or the secondary air A2 is prevented from flowing into the radially inner region R (see FIG. 9) of the nozzle 20 from the gas fuel F ejected from the main hole 32. can be done. That is, it is possible to delay the mixing of hydrogen and oxygen and further suppress the generation of NOx.
　尚、第２実施形態では、主孔３２は楕円形状を有していたが、本開示はこの形態に限定されない。第２実施形態の変形例では、図１０に例示するように、主孔３２は、弧形状（翼形状）を有する。この主孔３２の形状は、主孔３２の長手方向の一方側の一端６０と長手方向の一方側の他端６２とを通過し、ノズル２０の軸線Ｏ側とは反対側に突出するキャンバーライン６３（中心線）に基づいて形成される。主孔３２の形状のうち主孔３２の一端６０と他端６２とを接続し、キャンバーライン６３よりもノズル２０の軸線Ｏ側とは反対側に位置するラインを外側ライン６４とし、キャンバーライン６３よりもノズル２０の軸線Ｏ側に位置するラインを内側ライン６６とする。キャンバーライン６３と直交するとともに、外側ライン６４と内側ライン６６とを接続する直線のうち最も長い直線７０の長さをＷとし、キャンバーライン６３の長さをＬとすると、２×Ｗ＜Ｌを満たす。 Although the main hole 32 has an elliptical shape in the second embodiment, the present disclosure is not limited to this shape. In a modification of the second embodiment, as illustrated in FIG. 10, the main hole 32 has an arc shape (blade shape). The shape of the main hole 32 is a camber line passing through one longitudinal end 60 of the main hole 32 and the other longitudinal end 62 of the main hole 32 and protruding in the opposite direction to the axis O of the nozzle 20. 63 (center line). Of the shape of the main hole 32, a line connecting one end 60 and the other end 62 of the main hole 32 and located on the opposite side of the axis O side of the nozzle 20 from the camber line 63 is defined as an outer line 64. A line located on the side of the axis O of the nozzle 20 is defined as an inner line 66 . Let W be the length of the longest straight line 70 among the straight lines that intersect the camber line 63 and connect the outer line 64 and the inner line 66, and let L be the length of the camber line 63, then 2×W<L. Fulfill.
　＜第３実施形態＞
　本開示の第３実施形態に係るガスバーナ４について説明する。第３実施形態では、第１実施形態とは異なり主孔３２の噴出方向Ｄ４が二次空気出口４０と交差する方向に配向されている。第１実施形態の構成要件と同じものは同じ参照符号を付し、その詳細な説明は省略する。 <Third Embodiment>
A gas burner 4 according to a third embodiment of the present disclosure will be described. In the third embodiment, the ejection direction D4 of the main hole 32 is oriented in a direction intersecting the secondary air outlet 40 unlike the first embodiment. Components that are the same as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.
　図１１は、第３実施形態に係るガスバーナの構成を概略的に示す図である。第３実施形態では、図１１に例示するように、主噴出部２８は２つの主孔３２を含む。第１主孔３２Ｃ（３２）は、鉛直方向Ｄ２において、ノズル２０の軸線Ｏを挟んで第２主孔３２Ｄ（３２）とは反対側に位置している。第１主孔３２Ｃはノズル２０の軸線Ｏより上側に位置し、第２主孔３２Ｄはノズル２０の軸線Ｏより下側に位置している。 FIG. 11 is a diagram schematically showing the configuration of the gas burner according to the third embodiment. In the third embodiment, the main jet 28 includes two main holes 32, as illustrated in FIG. The first main hole 32C (32) is located on the opposite side of the axis O of the nozzle 20 from the second main hole 32D (32) in the vertical direction D2. The first main hole 32C is positioned above the axis O of the nozzle 20, and the second main hole 32D is positioned below the axis O of the nozzle 20. As shown in FIG.
　第１実施形態では、図１１に例示するように、副噴出部３０は２つの副孔３４を含む。第１副孔３４Ｃ（３４）は、左右方向Ｄ３において、ノズル２０の軸線Ｏを挟んで第２副孔３４Ｄ（３４）とは反対側に位置している。第１副孔３４Ｃはノズル２０の軸線Ｏより左側に位置し、第２副孔３４Ｄはノズル２０の軸線Ｏより右側に位置している。 In the first embodiment, as illustrated in FIG. 11, the sub ejection portion 30 includes two sub holes 34. The first secondary hole 34C (34) is located on the opposite side of the axis O of the nozzle 20 from the second secondary hole 34D (34) in the horizontal direction D3. The first secondary hole 34C is located on the left side of the axis O of the nozzle 20, and the second secondary hole 34D is located on the right side of the axis O of the nozzle 20. As shown in FIG.
　第１主孔３２Ｃ及び第２主孔３２Ｃのそれぞれは、左右方向Ｄ３において、第１副孔３４Ｃと第２副孔３４Ｄとの間に位置している。第１副孔３４Ｃ及び第２副孔３４Ｄのそれぞれは、鉛直方向Ｄ２において、第１主孔３２Ｃと第２主孔３２Ｄとの間に位置している。 Each of the first main hole 32C and the second main hole 32C is located between the first secondary hole 34C and the second secondary hole 34D in the horizontal direction D3. Each of the first secondary hole 34C and the second secondary hole 34D is positioned between the first primary hole 32C and the second primary hole 32D in the vertical direction D2.
　第１主孔３２Ｃは、第１副孔３４Ｃ及び第２副孔３４Ｄのそれぞれより大径である。第２主孔３２Ｄは、第１副孔３４Ｃ及び第２副孔３４Ｄのそれぞれより大径である。第１主孔３２Ｃと第２主孔３２Ｄとは同径である。第１副孔３４Ｃと第２副孔３４Ｄとは同径である。このように、主孔３２の開口面積の合計は副孔３４の開口面積の合計よりも大きく、主噴出部２８は副噴出部３０より多くのガス燃料Ｆを噴出できるようになっている。 The first main hole 32C has a larger diameter than each of the first secondary hole 34C and the second secondary hole 34D. The second main hole 32D has a larger diameter than each of the first secondary hole 34C and the second secondary hole 34D. The first main hole 32C and the second main hole 32D have the same diameter. The first secondary hole 34C and the second secondary hole 34D have the same diameter. In this way, the total opening area of the main holes 32 is larger than the total opening area of the sub-holes 34, so that the main jetting portion 28 can jet more fuel gas F than the sub-jetting portion 30 can.
　第３実施形態では、図１１に例示するように、正面視において、主孔３２の噴出方向Ｄ４は、二次空気出口４０と交差する方向に配向される。図１１に例示する形態では、第１主孔３２Ｃの噴出方向Ｄ４は上方であり、第２主孔３２Ｄの噴出方向Ｄ４は下方である。第１副孔３４Ｃの噴出方向Ｄ５は左方であり、第２副孔３４Ｄの噴出方向Ｄ５は右方である。幾つかの実施形態では、主孔３２の噴出方向Ｄ４を二次空気出口４０と交差する方向に配向するか否かを切り換え可能であるように、ノズル２０の先端部２６はノズル２０の軸線Ｏを中心として回転可能に構成されている。 In the third embodiment, as illustrated in FIG. 11, the ejection direction D4 of the main hole 32 is oriented in a direction that intersects the secondary air outlet 40 when viewed from the front. In the form illustrated in FIG. 11, the ejection direction D4 of the first main holes 32C is upward, and the ejection direction D4 of the second main holes 32D is downward. The ejection direction D5 of the first secondary hole 34C is leftward, and the ejection direction D5 of the second secondary hole 34D is rightward. In some embodiments, the tip 26 of the nozzle 20 is aligned with the axis O of the nozzle 20 so that the ejection direction D4 of the main hole 32 can be switched to be oriented transversely to the secondary air outlet 40 or not. is configured to be rotatable around the center.
　図１２は、第３実施形態に係る二次空気出口４０のレイアウトを説明するための図である。図１２に示すように、ノズル２０の軸線Ｏから鉛直方向Ｄ２に沿って直線状に仮想線７２を延ばす。この仮想線７２が一次空気出口３６の周縁と交差する点を第１交差点７４とする。さらに、この仮想線７２が二次空気出口４０の周縁のうち最初に交差する点を第２交差点７６とする。図１２に例示する形態では、第２交差点７６は、仮想線７２が内側出口４２の周縁のうち最初に交差する点である。第１交差点７４とノズル２０の軸線Ｏとの間の距離をｒとし、第２交差点７６とノズル２０の軸線Ｏとの間の距離をｄとすると、２×ｒ≦ｄを満たす。 FIG. 12 is a diagram for explaining the layout of the secondary air outlet 40 according to the third embodiment. As shown in FIG. 12, an imaginary line 72 is linearly extended from the axis O of the nozzle 20 along the vertical direction D2. A first crossing point 74 is a point where the imaginary line 72 intersects the periphery of the primary air outlet 36 . Further, the point at which the imaginary line 72 first intersects the periphery of the secondary air outlet 40 is defined as a second intersection point 76 . In the form illustrated in FIG. 12 , the second intersection point 76 is the point at which the imaginary line 72 first intersects the perimeter of the inner outlet 42 . If the distance between the first intersection 74 and the axis O of the nozzle 20 is r, and the distance between the second intersection 76 and the axis O of the nozzle 20 is d, 2×r≦d is satisfied.
　第３実施形態によれば、二次空気出口４０は、２×ｒ≦ｄを満たすように、ノズル２０の先端部２６から離間しているので、主孔３２から噴出されるガス燃料Ｆと二次空気出口４０から流出する二次空気Ａ２や低酸素二次空気Ａ３との接触を遅らせることができる。このため、水素と酸素との混合を緩やかにすることで燃焼空間６の昇温を抑制し、ＮＯｘの発生を抑制することができる。 According to the third embodiment, the secondary air outlet 40 is separated from the tip portion 26 of the nozzle 20 so as to satisfy 2×r≦d. Contact with the secondary air A2 or the low-oxygen secondary air A3 flowing out from the secondary air outlet 40 can be delayed. Therefore, by slowing down the mixing of hydrogen and oxygen, it is possible to suppress the temperature rise in the combustion space 6 and suppress the generation of NOx.
　本開示では、図２に例示して説明したように、火炉２は矩形状の燃焼空間６を有し、４つのガスバーナ４のそれぞれが、燃焼空間６の矩形状の角部２１にガス燃料Ｆを噴出するように火炉２に設けられていたが、本開示はこの形態に限定されない。図１３Ａ、図１３Ｂ、及び図１３Ｃのそれぞれは、幾つかの実施形態に係る火炉２の内部構成を概略的に示す図である。 In the present disclosure, the furnace 2 has a rectangular combustion space 6 and each of the four gas burners 4 is positioned at a rectangular corner 21 of the combustion space 6 as illustrated and described in FIG. , the present disclosure is not limited to this form. Each of Figures 13A, 13B, and 13C is a diagram schematically showing the internal configuration of a furnace 2 according to some embodiments.
　幾つかの実施形態では、図１３Ａに例示するように、４つのガスバーナ４（４Ａ、４Ｂ、４Ｃ、４Ｄ）のそれぞれは、火炉１１を上方から見たときに火炎Ｘが燃焼空間６の中央部２３で旋回する旋回燃焼を行うように配置されている。第１ガスバーナ４Ａは、第１炉壁８の壁面に配置されている。第２ガスバーナ４Ｂは、第２炉壁１０の壁面に配置されている。第３ガスバーナ４Ｃは、第３炉壁１２の壁面に配置されている。第４ガスバーナ４Ｄは、第４炉壁１４の壁面に配置されている。 In some embodiments, as illustrated in FIG. 13A, each of the four gas burners 4 (4A, 4B, 4C, 4D) has a flame X extending from the center of the combustion space 6 when the furnace 11 is viewed from above. At 23 it is arranged for swirling combustion. The first gas burner 4A is arranged on the wall surface of the first furnace wall 8 . The second gas burner 4B is arranged on the wall surface of the second furnace wall 10 . A third gas burner 4</b>C is arranged on the wall surface of the third furnace wall 12 . A fourth gas burner 4</b>D is arranged on the wall surface of the fourth furnace wall 14 .
　幾つかの実施形態では、図１３Ｂに例示するように、燃焼空間６は８角形状を有する。火炉２は、第１炉壁８の一端部１６と第３炉壁１２の第１炉壁１６側の一端部８０とを接続する第１コーナ部８２と、第３炉壁１２の第２炉壁１０側の他端部８４と第２炉壁１０の一端部１８とを接続する第２コーナ部８６と、第２炉壁１０の他端部１９と第４炉壁１４の第２炉壁１０側の他端部８８とを接続する第３コーナ部９０と、第４炉壁１４の第１炉壁８側の一端部９２と第１炉壁８の他端部１７とを接続する第４コーナ部９４とを含む。火炉２の燃焼空間６は、第１炉壁８、第２炉壁１０、第３炉壁１２、第４炉壁１４、第１コーナ部８２、第２コーナ部８６、第３コーナ部９０及び第４コーナ部９４によって囲われることで８角形状に形成されている。第１ガスバーナ４Ａは、第４コーナ部９４の壁面に配置されている。第２ガスバーナ４Ｂは、第２コーナ部８６の壁面に配置されている。第３ガスバーナ４Ｃは、第１コーナ部８２の壁面に配置されている。第４ガスバーナ４Ｄは、第３コーナ部９０の壁面に配置されている。 In some embodiments, the combustion space 6 has an octagonal shape, as illustrated in FIG. 13B. The furnace 2 includes a first corner portion 82 connecting one end portion 16 of the first furnace wall 8 and one end portion 80 of the third furnace wall 12 on the first furnace wall 16 side, and a second furnace wall of the third furnace wall 12. A second corner portion 86 connecting the other end portion 84 on the side of the wall 10 and the one end portion 18 of the second furnace wall 10, the other end portion 19 of the second furnace wall 10 and the second furnace wall of the fourth furnace wall 14 A third corner portion 90 connecting the other end portion 88 on the 10th side, and a third corner portion 90 connecting the one end portion 92 of the fourth furnace wall 14 on the side of the first furnace wall 8 and the other end portion 17 of the first furnace wall 8 . 4 corners 94 . The combustion space 6 of the furnace 2 includes a first furnace wall 8, a second furnace wall 10, a third furnace wall 12, a fourth furnace wall 14, a first corner portion 82, a second corner portion 86, a third corner portion 90 and It is formed in an octagonal shape by being surrounded by the fourth corner portion 94 . The first gas burner 4A is arranged on the wall surface of the fourth corner portion 94 . The second gas burner 4B is arranged on the wall surface of the second corner portion 86 . The third gas burner 4C is arranged on the wall surface of the first corner portion 82 . The fourth gas burner 4D is arranged on the wall surface of the third corner portion 90. As shown in FIG.
　幾つかの実施形態では、図１３Ｃに例示するように、燃焼空間６は長方形状を有する。図１３Ｃに例示する形態では、第１炉壁８及び第２炉壁１０のそれぞれが燃焼空間６の長方形状の短辺を形成し、第３炉壁１２及び第４炉壁１４のそれぞれが燃焼空間６の長方形状の長辺を形成している。火炉２には８つのガスバーナ４が設けられており、４つのガスバーナ４で火炎Ｘが旋回燃焼を行うように配置されている。図１３に例示する形態では、８つのガスバーナ４で２つの火炎Ｘが旋回燃焼を行っている。８つのガスバーナ４のそれぞれは、第３炉壁１２の壁面、又は第４炉壁１４の壁面の何れかに配置されている。 In some embodiments, the combustion space 6 has a rectangular shape, as illustrated in FIG. 13C. In the form illustrated in FIG. 13C, the first furnace wall 8 and the second furnace wall 10 each form a rectangular short side of the combustion space 6, and the third furnace wall 12 and the fourth furnace wall 14 each form a combustion chamber. It forms the rectangular long side of the space 6 . Eight gas burners 4 are provided in the furnace 2, and the four gas burners 4 are arranged so that the flame X performs swirling combustion. In the form illustrated in FIG. 13 , two flames X are performing swirling combustion with eight gas burners 4 . Each of the eight gas burners 4 is arranged on either the wall surface of the third furnace wall 12 or the wall surface of the fourth furnace wall 14 .
　上記各実施形態に記載の内容は、例えば以下のように把握される。 The contents described in each of the above embodiments can be understood, for example, as follows.
　［１］本開示に係るガスバーナ（４）は、
　水素を含むガス燃料（Ｆ）を燃焼するためのガスバーナであって、
　前記ガス燃料を噴出する主噴出部（２８）であって少なくとも１つの主孔（３２）を含む主噴出部、及び前記主噴出部よりも少量の前記ガス燃料を噴出する副噴出部（３０）であって少なくとも１つの副孔（３４）を含む副噴出部、が先端部（２６）に形成されるノズル（２０）と、
　前記ノズルの軸線方向（Ｄ１）に沿って視認した正面視において、前記ノズルの前記先端部の周囲を囲むとともに、一次空気（Ａ１）が流出する一次空気出口（３６）を形成する一次空気流路部（２２）と、
　前記正面視において、前記一次空気出口の上方または下方に位置するとともに、二次空気（Ａ２）が流出する二次空気出口（４０）を形成する二次空気流路部（２４）と、を備え、
　前記正面視において、前記少なくとも１つの副孔の噴出方向（Ｄ５）は、前記二次空気出口と交差する方向に配向され、前記少なくとも１つの主孔の噴出方向（Ｄ４）は、前記二次空気出口と交差しない方向に配向される。 [1] The gas burner (4) according to the present disclosure is
A gas burner for burning gas fuel (F) containing hydrogen,
A main ejection portion (28) for ejecting the gas fuel, the main ejection portion including at least one main hole (32), and a sub ejection portion (30) for ejecting a smaller amount of the gas fuel than the main ejection portion. a nozzle (20) formed in a tip (26) with a secondary jet including at least one secondary hole (34);
In a front view along the axial direction (D1) of the nozzle, the primary air flow path surrounds the tip of the nozzle and forms a primary air outlet (36) through which the primary air (A1) flows out. a part (22);
a secondary air flow path portion (24) positioned above or below the primary air outlet in the front view and forming a secondary air outlet (40) through which the secondary air (A2) flows out; ,
In the front view, the ejection direction (D5) of the at least one secondary hole is oriented in a direction intersecting the secondary air outlet, and the ejection direction (D4) of the at least one main hole is the secondary air outlet. Oriented in a direction that does not intersect the outlet.
　水素は従来からのガス燃料に含まれる成分と比較して燃焼速度が大きい。このため、ガス燃料に水素が含まれる場合、ガスバーナの保炎のために用いられるガス燃料の量を少なくすることができる。一方で、水素と酸素との混合が速やかに行われるので、ガス燃料が燃焼される燃焼空間の温度を速やかに高くし、窒素酸化物（ＮＯｘ）の発生を促進してしまう。上記［１］に記載の構成によれば、副噴出部の副孔から噴出される少量のガス燃料を、二次空気出口から流出する二次空気と速やかに接触させて、保炎性を高めることができる。つまり、少量のガス燃料で保炎性を確保することができる。さらに、主噴出部の主孔から噴出される大量のガス燃料は、副孔から噴出されるガス燃料よりも遅れて、二次空気出口から流出する二次空気と接触する。つまり、主孔から噴出されるガス燃料は、ノズルの先端部から離間した比較的酸素濃度の低い領域に流れ込む。このため、水素と酸素との混合を緩やかにするとともに、緩慢燃焼の促進が行われて、燃焼空間の昇温を抑制し、ＮＯｘの発生を抑制することができる。よって、水素を含むガス燃料を用いる場合に好適な燃焼状態（保炎性の確保とＮＯｘの発生の抑制）を実現することができる。 　Hydrogen has a higher combustion speed than the components contained in conventional gas fuel. Therefore, when the gas fuel contains hydrogen, the amount of gas fuel used for flame stabilization of the gas burner can be reduced. On the other hand, since the hydrogen and oxygen are rapidly mixed, the temperature of the combustion space where the gas fuel is burned quickly rises, promoting the generation of nitrogen oxides (NOx). According to the configuration described in [1] above, a small amount of gas fuel ejected from the secondary hole of the secondary ejection portion is brought into rapid contact with the secondary air flowing out from the secondary air outlet, thereby improving flame stability. be able to. That is, it is possible to ensure flame stability with a small amount of gas fuel. Furthermore, a large amount of gas fuel ejected from the main hole of the main ejection portion contacts the secondary air flowing out from the secondary air outlet later than the gas fuel ejected from the secondary hole. In other words, the gaseous fuel ejected from the main hole flows into a region of relatively low oxygen concentration separated from the tip of the nozzle. Therefore, the mixture of hydrogen and oxygen is moderated, and slow combustion is promoted, thereby suppressing the temperature rise in the combustion space and suppressing the generation of NOx. Therefore, it is possible to achieve a favorable combustion state (ensure flame stabilization and suppress NOx generation) when using a gas fuel containing hydrogen.
　［２］幾つかの実施形態では、上記［１］に記載の構成において、
　前記二次空気出口は、内側出口（４２）と前記内側出口より前記一次空気出口から離れて位置する外側出口（４４）とを含み、
　前記外側出口は、前記二次空気が流出するように構成され、
　前記内側出口は、前記外側出口から流出される前記二次空気より酸素濃度の低い低酸素二次空気（Ａ３）が流出するように構成される。 [2] In some embodiments, in the configuration described in [1] above,
said secondary air outlet includes an inner outlet (42) and an outer outlet (44) located further from said primary air outlet than said inner outlet;
the outer outlet is configured to allow the secondary air to flow out;
The inner outlet is configured to flow out low-oxygen secondary air (A3) having a lower oxygen concentration than the secondary air flowing out from the outer outlet.
　上記［２］に記載の構成によれば、外側出口から流出する二次空気に先行して内側出口から流出する低酸素二次空気を、主孔から噴出される水素ガス燃料に接触させる。このため、水素と酸素との混合をさらに緩やかにし、燃焼空間の昇温をさらに抑制することができる。 According to the configuration described in [2] above, the low-oxygen secondary air flowing out from the inner outlet prior to the secondary air flowing out from the outer outlet is brought into contact with the hydrogen gas fuel ejected from the main hole. Therefore, the mixture of hydrogen and oxygen can be made more moderate, and the temperature rise in the combustion space can be further suppressed.
　［３］幾つかの実施形態では、上記［１］又は［２］に記載の構成において、
　前記ノズルの前記先端部を鉛直方向（Ｄ２）に沿って視認した場合に、前記主孔の噴出方向と前記ノズルの前記軸線方向とによって形成される角度をθ１とし、
　前記ノズルの前記先端部を前記ノズルの前記軸線方向及び前記鉛直方向のそれぞれと直交する方向に沿って視認した場合に、前記副孔の噴出方向と前記ノズルの前記軸線方向とによって形成される角度をθ２とすると、
　θ１＜θ２を満たす。 [3] In some embodiments, in the configuration described in [1] or [2] above,
Let θ1 be an angle formed by the ejection direction of the main hole and the axial direction of the nozzle when the tip of the nozzle is viewed in the vertical direction (D2),
An angle formed by the ejection direction of the secondary hole and the axial direction of the nozzle when the tip of the nozzle is viewed along a direction perpendicular to each of the axial direction and the vertical direction of the nozzle. is θ2,
It satisfies θ1<θ2.
　上記［３］に記載の構成によれば、副噴出部の副孔から噴出される少量のガス燃料と二次空気との接触を速めつつ、主噴出部の主孔から噴出される大量のガス燃料と二次空気との接触を遅らせることができる。 According to the configuration described in [3] above, a large amount of gas is ejected from the main hole of the main ejection portion while speeding up contact between a small amount of gas fuel ejected from the secondary hole of the secondary ejection portion and the secondary air. Contact between fuel and secondary air can be delayed.
　［４］幾つかの実施形態では、上記［３］に記載の構成において、
　前記ノズルの前記先端部に設けられ、前記一次空気出口に向かうにつれて前記ノズルの軸線から離間する保炎面（５２）を有する保炎器（５０）をさらに備え、
　前記保炎面と前記ノズルの前記軸線方向とによって形成される角度をθ３とすると、
　θ２≦θ３を満たす。 [4] In some embodiments, in the configuration described in [3] above,
further comprising a flame stabilizer (50) provided at the tip of the nozzle and having a flame holding surface (52) spaced apart from the axis of the nozzle toward the primary air outlet;
Assuming that the angle formed by the flame-stabilizing surface and the axial direction of the nozzle is θ3,
θ2≦θ3 is satisfied.
　上記［４］に記載の構成によれば、副噴出部の副孔から噴出されるガス燃料（より具体的には、副孔から噴出されるガス燃料と一次空気との接触によって発生する火炎）による保炎器の損傷を抑制することができる。 According to the configuration described in [4] above, the gas fuel ejected from the secondary hole of the secondary ejection portion (more specifically, the flame generated by the contact between the gas fuel ejected from the secondary hole and the primary air) It is possible to suppress damage to the flame stabilizer due to
　［５］幾つかの実施形態では、上記［３］又は［４］に記載の構成において、
　１５度＜θ１＜４５度を満たす。 [5] In some embodiments, in the configuration described in [3] or [4] above,
It satisfies 15 degrees<θ1<45 degrees.
　θ１が４５度を超えると、燃焼空間の圧力変動による燃焼振動のポテンシャルが大きくなる。また、θ１が１５度未満になると、長炎化が過剰となり熱吸収特性に影響を与える。このため、上記［５］に記載の構成によれば、燃焼振動を抑制できると共に、適度な長炎化による緩慢燃焼で燃焼空間の昇温を抑制することができる。 When θ1 exceeds 45 degrees, the potential for combustion oscillation due to pressure fluctuations in the combustion space increases. Further, when θ1 is less than 15 degrees, the flame becomes excessively long, which affects the heat absorption characteristics. For this reason, according to the configuration described in [5] above, it is possible to suppress the combustion oscillation, and to suppress the temperature rise of the combustion space by moderately lengthening the flame to achieve slow combustion.
　［６］幾つかの実施形態では、上記［３］又は［４］に記載の構成において、
　３５度＜θ２＜５５度を満たす。 [6] In some embodiments, in the configuration described in [3] or [4] above,
It satisfies 35 degrees<θ2<55 degrees.
　θ２が５５度を超えると、保炎器近傍での保炎性が強くなり過ぎるため、保炎器の焼損ポテンシャルが大きくなると共に、ＮＯｘの発生を促進させる虞がある。また、θ２が３５度未満であると、保炎効果が弱くなり振動ポテンシャルが上昇する。このため、上記［６］に記載の構成によれば、燃焼振動、保炎器の損傷、及びＮＯｘの発生をバランスよく抑制することができる。 If θ2 exceeds 55 degrees, the flame stabilizing properties in the vicinity of the flame stabilizer become too strong, which may increase the burnout potential of the flame stabilizer and promote the generation of NOx. On the other hand, when θ2 is less than 35 degrees, the flame holding effect is weakened and the vibration potential is increased. Therefore, according to the configuration described in [6] above, combustion oscillation, damage to the flame stabilizer, and generation of NOx can be suppressed in a well-balanced manner.
　［７］幾つかの実施形態では、上記［１］から［６］の何れか１つに記載の構成において、
　前記正面視において、前記少なくとも１つの主孔は長手形状を有し、前記少なくとも１つの主孔の長手方向の長さをＬ、前記少なくとも１つの主孔の短手方向の長さをＷとすると、
　２×Ｗ＜Ｌを満たす。 [7] In some embodiments, in the configuration described in any one of [1] to [6] above,
When viewed from the front, the at least one main hole has a longitudinal shape, and the length in the longitudinal direction of the at least one main hole is L, and the length in the short direction of the at least one main hole is W. ,
2×W<L is satisfied.
　上記［７］に記載の構成によれば、一次空気又は二次空気が主孔から噴出されるガス燃料よりノズルの径方向の内側の領域に流れ込むことを抑制することができる。つまり、水素と酸素との混合を遅らせ、ＮＯｘの発生をさらに抑制することができる。 According to the configuration described in [7] above, it is possible to suppress the primary air or secondary air from flowing into the radially inner region of the nozzle from the gas fuel ejected from the main hole. That is, it is possible to delay the mixing of hydrogen and oxygen and further suppress the generation of NOx.
　［８］幾つかの実施形態では、上記［１］から［７］の何れか１つに記載の構成において、
　前記主噴出部は、前記少なくとも１つの副孔より大径の前記少なくとも１つの主孔を含む。 [8] In some embodiments, in the configuration described in any one of [1] to [7] above,
The main ejection part includes the at least one main hole having a larger diameter than the at least one secondary hole.
　上記［８］に記載の構成によれば、主噴出部は、副噴出部よりも大量のガス燃料の噴出を実現することができる。 According to the configuration described in [8] above, the main ejection part can eject a larger amount of gas fuel than the sub ejection part.
　［９］幾つかの実施形態では、上記［１］から［８］の何れか１つに記載の構成において、
　前記主噴出部は、前記少なくとも１つの副孔の数より多い前記複数の主孔を含む。 [9] In some embodiments, in the configuration described in any one of [1] to [8] above,
The main ejection part includes the plurality of main holes, which is greater than the number of the at least one secondary holes.
　上記［９］に記載の構成によれば、主噴出部は、副噴出部よりも大量のガス燃料の噴出を実現することができる。 According to the configuration described in [9] above, the main ejection portion can eject a larger amount of gas fuel than the sub ejection portion.
　［１０］幾つかの実施形態では、上記［１］から［９］の何れか１つに記載の構成において、
　前記少なくとも１つの主孔は、第１主孔（３２Ａ）と第２主孔（３２Ｂ）とを含み、
　前記正面視において、前記第１主孔は、左右方向（Ｄ３）において前記ノズルの軸線を挟んで前記第２主孔とは反対側に位置し、
　前記第１主孔の噴出方向は、前記第２主孔の噴出方向と反対となるように配向されている。 [10] In some embodiments, in the configuration described in any one of [1] to [9] above,
the at least one main hole includes a first main hole (32A) and a second main hole (32B);
In the front view, the first main hole is located on the opposite side of the second main hole across the axis of the nozzle in the left-right direction (D3),
The ejection direction of the first main holes is oriented so as to be opposite to the ejection direction of the second main holes.
　上記［１０］に記載の構成によれば、主噴出部は、左右方向に幅広くガス燃料を噴出することができる。 According to the configuration described in [10] above, the main ejection portion can eject the gas fuel widely in the left-right direction.
　［１１］幾つかの実施形態では、上記［１］から［１０］の何れか１つに記載の構成において、
　前記少なくとも１つの副孔は、第１副孔（３４Ａ）と第２副孔（３４Ｂ）とを含み、
　前記正面視において、前記第１副孔は、鉛直方向において前記ノズルの軸線を挟んで前記第２副孔とは反対側に位置し、
　前記第１副孔の噴出方向は、前記第２副孔の噴出方向と反対となるように配向されている。 [11] In some embodiments, in the configuration described in any one of [1] to [10] above,
the at least one subhole includes a first subhole (34A) and a second subhole (34B);
In the front view, the first secondary hole is located on the opposite side of the second secondary hole with respect to the axis of the nozzle in the vertical direction,
The ejection direction of the first sub-hole is oriented so as to be opposite to the ejection direction of the second sub-hole.
　上記［１１］に記載の構成によれば、副噴出部は、上下方向の両方にガス燃料を噴出することができる。 According to the configuration described in [11] above, the sub-injection part can inject gas fuel in both the vertical direction.
　［１２］本開示に係るガスバーナは、
　水素を含むガス燃料を燃焼するためのガスバーナであって、
　前記ガス燃料を噴出する主噴出部であって少なくとも１つの主孔を含む主噴出部、及び前記主噴出部よりも少量の前記ガス燃料を噴出する副噴出部であって少なくとも１つの副孔を含む副噴出部、が先端部に形成されるノズルと、
　前記ノズルの軸線方向に沿って視認した正面視において、前記ノズルの前記先端部の周囲を囲むとともに、一次空気が流出する一次空気出口を形成する一次空気流路部と、
　前記正面視において、前記一次空気出口の上方または下方に位置するとともに、二次空気が流出する二次空気出口を形成する二次空気流路部と、を備え、
　前記ノズルの軸線から鉛直方向に沿って直線状に仮想線（７２）を延ばした場合に、
　前記仮想線が前記一次空気出口の周縁と交差する第１交差点（７４）と前記ノズルの前記軸線との間の距離をｒとし、前記仮想線が前記二次空気出口の周縁のうち最初に交差する第２交差点（７６）と前記ノズルの前記軸線との間の距離をｄとすると、
　２×ｒ≦ｄを満たし、
　前記正面視において、前記少なくとも１つの主孔の噴出方向は、前記二次空気出口と交差する方向に配向される。 [12] The gas burner according to the present disclosure is
A gas burner for burning gas fuel containing hydrogen,
A main ejection portion that ejects the gas fuel and includes at least one main hole, and a sub ejection portion that ejects a smaller amount of the gas fuel than the main ejection portion and has at least one sub hole. a nozzle formed at the tip thereof with a sub-jetting part including;
a primary air flow path portion that surrounds the periphery of the tip portion of the nozzle and forms a primary air outlet through which the primary air flows out, in a front view viewed along the axial direction of the nozzle;
a secondary air flow path portion positioned above or below the primary air outlet in the front view and forming a secondary air outlet through which the secondary air flows,
When an imaginary line (72) is extended linearly along the vertical direction from the axis of the nozzle,
Let r be the distance between a first intersection point (74) where the imaginary line intersects the circumference of the primary air outlet and the axis of the nozzle, and the imaginary line intersects first among the circumferences of the secondary air outlet. Let d be the distance between the second intersection point (76) and said axis of said nozzle,
satisfying 2 × r ≤ d,
In the front view, the ejection direction of the at least one main hole is oriented in a direction intersecting with the secondary air outlet.
　上記［１２］に記載の構成によれば、二次空気出口は、２×ｒ≦ｄを満たすように、主噴出部が形成されるノズルの先端部から離間しているので、主噴出部の主孔から噴出されるガス燃料と二次空気出口から流出する二次空気との接触を遅らせることができる。このため、水素と酸素との混合を緩やかにすることで燃焼空間の昇温を抑制し、ＮＯｘの発生を抑制することができる。 According to the configuration described in [12] above, the secondary air outlet is spaced apart from the tip of the nozzle in which the main ejection portion is formed so as to satisfy 2×r≦d. It is possible to delay the contact between the gaseous fuel ejected from the main hole and the secondary air flowing out from the secondary air outlet. Therefore, by slowing the mixing of hydrogen and oxygen, it is possible to suppress the temperature rise in the combustion space and suppress the generation of NOx.
　［１３］幾つかの実施形態では、上記［１］から［１２］の何れか１つに記載の構成において、
　前記ガスバーナは、炉に面する端面の形状が鉛直方向に沿って長手方向を有する矩形状の角型バーナである。 [13] In some embodiments, in the configuration described in any one of [1] to [12] above,
The gas burner is a rectangular burner whose end surface facing the furnace has a longitudinal direction along the vertical direction.
　上記［１３］に記載の構成によれば、上記［１］から［１２］の何れか１つに記載の構成を、角型バーナに適用できる。 According to the configuration described in [13] above, the configuration described in any one of [1] to [12] above can be applied to a square burner.
　［１４］幾つかの実施形態では、燃焼設備は、
　火炉（２）と、
　前記火炉に設けられる上記［１］から［１３］の何れか１つに記載のガスバーナと、を備える。 [14] In some embodiments, the combustion facility comprises:
a furnace (2);
and the gas burner according to any one of [1] to [13] above, which is provided in the furnace.
　上記［１４］に記載の構成によれば、水素を含むガス燃料を用いるガスバーナを備える場合であっても、火炉内を好適な燃焼状態に維持することができる。 According to the configuration described in [14] above, even when a gas burner using gas fuel containing hydrogen is provided, the inside of the furnace can be maintained in a suitable combustion state.
１　　　燃焼設備
２　　　火炉
４　　　ガスバーナ
２０　　ノズル
２２　　一次空気流路部
２４　　二次空気流路部
２６　　ノズルの先端部
２８　　主噴出部
３０　　副噴出部
３２　　主孔
３２Ａ　第１主孔
３２Ｂ　第２主孔
３４　　副孔
３４Ａ　第１副孔
３４Ｂ　第２副孔
３６　　一次空気出口
４０　　二次空気出口
４２　　内側出口
４４　　外側出口
５０　　保炎器
５２　　保炎面
７２　　仮想線
７４　　第１交差点
７６　　第２交差点
 
Ａ　　　燃焼用空気
Ａ１　　一次空気
Ａ２　　二次空気
Ａ３　　低酸素二次空気
Ｄ１　　軸線方向
Ｄ２　　鉛直方向
Ｄ３　　左右方向
Ｄ４　　主孔の噴出方向
Ｄ５　　副孔の噴出方向
Ｆ　　　ガス燃料
Ｇ　　　排ガス
Ｏ　　　ノズルの軸線

  1 Combustion equipment 2 Furnace 4 Gas burner 20 Nozzle 22 Primary air flow path 24 Secondary air flow path 26 Nozzle tip 28 Main ejection part 30 Sub ejection part 32 Main hole 32A First main hole 32B Second main hole 34 Sub Hole 34A First secondary hole 34B Second secondary hole 36 Primary air outlet 40 Secondary air outlet 42 Inner outlet 44 Outer outlet 50 Flame stabilizer 52 Flame holding surface 72 Virtual line 74 First intersection 76 Second intersection
A Combustion air A1 Primary air A2 Secondary air A3 Low-oxygen secondary air D1 Axial direction D2 Vertical direction D3 Left-right direction D4 Main hole ejection direction D5 Secondary hole ejection direction F Gas fuel G Exhaust gas O Nozzle axis

Claims (14)

  1. 　水素を含むガス燃料を燃焼するためのガスバーナであって、
    　前記ガス燃料を噴出する主噴出部であって少なくとも１つの主孔を含む主噴出部、及び前記主噴出部よりも少量の前記ガス燃料を噴出する副噴出部であって少なくとも１つの副孔を含む副噴出部、が先端部に形成されるノズルと、
    　前記ノズルの軸線方向に沿って視認した正面視において、前記ノズルの前記先端部の周囲を囲むとともに、一次空気が流出する一次空気出口を形成する一次空気流路部と、
    　前記正面視において、前記一次空気出口の上方または下方に位置するとともに、二次空気が流出する二次空気出口を形成する二次空気流路部と、を備え、
    　前記正面視において、前記少なくとも１つの副孔の噴出方向は、前記二次空気出口と交差する方向に配向され、前記少なくとも１つの主孔の噴出方向は、前記二次空気出口と交差しない方向に配向される、
    　ガスバーナ。     A gas burner for burning gas fuel containing hydrogen,
    A main ejection portion that ejects the gas fuel and includes at least one main hole, and a sub ejection portion that ejects a smaller amount of the gas fuel than the main ejection portion and has at least one sub hole. a nozzle formed at the tip thereof with a sub-jetting part including;
    a primary air flow path portion that surrounds the periphery of the tip portion of the nozzle and forms a primary air outlet through which the primary air flows out, in a front view viewed along the axial direction of the nozzle;
    a secondary air flow path portion positioned above or below the primary air outlet in the front view and forming a secondary air outlet through which the secondary air flows,
    When viewed from the front, the ejection direction of the at least one secondary hole is oriented in the direction intersecting the secondary air outlet, and the ejection direction of the at least one main hole is the direction not intersecting the secondary air outlet. oriented,
    gas burner.
  2. 　前記二次空気出口は、内側出口と前記内側出口より前記一次空気出口から離れて位置する外側出口とを含み、
    　前記外側出口は、前記二次空気が流出するように構成され、
    　前記内側出口は、前記外側出口から流出される前記二次空気より酸素濃度の低い低酸素二次空気が流出するように構成される、
    　請求項１に記載のガスバーナ。     said secondary air outlet includes an inner outlet and an outer outlet located further from said primary air outlet than said inner outlet;
    the outer outlet is configured to allow the secondary air to flow out;
    The inner outlet is configured to flow out low-oxygen secondary air having a lower oxygen concentration than the secondary air flowing out from the outer outlet.
    A gas burner according to claim 1.
  3. 　前記ノズルの前記先端部を鉛直方向に沿って視認した場合に、前記主孔の噴出方向と前記ノズルの前記軸線方向とによって形成される角度をθ１とし、
    　前記ノズルの前記先端部を前記ノズルの前記軸線方向及び前記鉛直方向のそれぞれと直交する方向に沿って視認した場合に、前記副孔の噴出方向と前記ノズルの前記軸線方向とによって形成される角度をθ２とすると、
    　θ１＜θ２を満たす、
    　請求項１又は２に記載のガスバーナ。     Let θ1 be an angle formed by the ejection direction of the main hole and the axial direction of the nozzle when the tip of the nozzle is viewed in the vertical direction,
    An angle formed by the ejection direction of the secondary hole and the axial direction of the nozzle when the tip of the nozzle is viewed along a direction perpendicular to each of the axial direction and the vertical direction of the nozzle. is θ2,
    satisfying θ1<θ2,
    A gas burner according to claim 1 or 2.
  4. 　前記ノズルの前記先端部に設けられ、前記一次空気出口に向かうにつれて前記ノズルの軸線から離間する保炎面を有する保炎器をさらに備え、
    　前記保炎面と前記ノズルの前記軸線方向とによって形成される角度をθ３とすると、
    　θ２≦θ３を満たす、
    　請求項３に記載のガスバーナ。     further comprising a flame stabilizer provided at the tip of the nozzle and having a flame holding surface that separates from the axis of the nozzle toward the primary air outlet;
    Assuming that the angle formed by the flame-stabilizing surface and the axial direction of the nozzle is θ3,
    satisfying θ2≦θ3,
    A gas burner according to claim 3.
  5. 　１５度＜θ１＜４５度を満たす、
    　請求項３に記載のガスバーナ。     satisfying 15 degrees < θ1 < 45 degrees,
    A gas burner according to claim 3.
  6. 　３５度＜θ２＜５５度を満たす、
    　請求項３に記載のガスバーナ。     satisfying 35 degrees < θ2 < 55 degrees,
    A gas burner according to claim 3.
  7. 　前記正面視において、前記少なくとも１つの主孔は長手形状を有し、前記少なくとも１つの主孔の長手方向の長さをＬ、前記少なくとも１つの主孔の短手方向の長さをＷとすると、
    　２×Ｗ＜Ｌを満たす、
    　請求項１又は２に記載のガスバーナ。     When viewed from the front, the at least one main hole has a longitudinal shape, and the length in the longitudinal direction of the at least one main hole is L, and the length in the short direction of the at least one main hole is W. ,
    satisfying 2×W<L,
    A gas burner according to claim 1 or 2.
  8. 　前記主噴出部は、前記少なくとも１つの副孔より大径の前記少なくとも１つの主孔を含む、
    　請求項１又は２に記載のガスバーナ。     The main ejection part includes the at least one main hole having a larger diameter than the at least one secondary hole,
    A gas burner according to claim 1 or 2.
  9. 　前記主噴出部は、前記少なくとも１つの副孔の数より多い前記複数の主孔を含む、
    　請求項１又は２に記載のガスバーナ。     the main ejection part includes the plurality of main holes, which is greater in number than the at least one secondary hole,
    A gas burner according to claim 1 or 2.
  10. 　前記少なくとも１つの主孔は、第１主孔と第２主孔とを含み、
    　前記正面視において、前記第１主孔は、左右方向において前記ノズルの軸線を挟んで前記第２主孔とは反対側に位置し、
    　前記第１主孔の噴出方向は、前記第２主孔の噴出方向と反対となるように配向されている、
    　請求項１又は２に記載のガスバーナ。     the at least one main hole includes a first main hole and a second main hole;
    In the front view, the first main hole is located on the opposite side of the second main hole across the axis of the nozzle in the left-right direction,
    The ejection direction of the first main hole is oriented so as to be opposite to the ejection direction of the second main hole,
    A gas burner according to claim 1 or 2.
  11. 　前記少なくとも１つの副孔は、第１副孔と第２副孔とを含み、
    　前記正面視において、前記第１副孔は、鉛直方向において前記ノズルの軸線を挟んで前記第２副孔とは反対側に位置し、
    　前記第１副孔の噴出方向は、前記第２副孔の噴出方向と反対となるように配向されている、
    　請求項１又は２に記載のガスバーナ。     the at least one subhole includes a first subhole and a second subhole;
    In the front view, the first secondary hole is located on the opposite side of the second secondary hole with respect to the axis of the nozzle in the vertical direction,
    the ejection direction of the first sub-hole is oriented so as to be opposite to the ejection direction of the second sub-hole;
    A gas burner according to claim 1 or 2.
  12. 　水素を含むガス燃料を燃焼するためのガスバーナであって、
    　前記ガス燃料を噴出する主噴出部であって少なくとも１つの主孔を含む主噴出部、及び前記主噴出部よりも少量の前記ガス燃料を噴出する副噴出部であって少なくとも１つの副孔を含む副噴出部、が先端部に形成されるノズルと、
    　前記ノズルの軸線方向に沿って視認した正面視において、前記ノズルの前記先端部の周囲を囲むとともに、一次空気が流出する一次空気出口を形成する一次空気流路部と、
    　前記正面視において、前記一次空気出口の上方または下方に位置するとともに、二次空気が流出する二次空気出口を形成する二次空気流路部と、を備え、
    　前記ノズルの軸線から鉛直方向に沿って直線状に仮想線を延ばした場合に、
    　前記仮想線が前記一次空気出口の周縁と交差する第１交差点と前記ノズルの前記軸線との間の距離をｒとし、前記仮想線が前記二次空気出口の周縁のうち最初に交差する第２交差点と前記ノズルの前記軸線との間の距離をｄとすると、
    　２×ｒ≦ｄを満たし、
    　前記正面視において、前記少なくとも１つの主孔の噴出方向は、前記二次空気出口と交差する方向に配向される、
    　ガスバーナ。     A gas burner for burning gas fuel containing hydrogen,
    A main ejection portion that ejects the gas fuel and includes at least one main hole, and a sub ejection portion that ejects a smaller amount of the gas fuel than the main ejection portion and has at least one sub hole. a nozzle formed at the tip thereof with a sub-jetting part including;
    a primary air flow path portion that surrounds the periphery of the tip portion of the nozzle and forms a primary air outlet through which the primary air flows out, in a front view viewed along the axial direction of the nozzle;
    a secondary air flow path portion positioned above or below the primary air outlet in the front view and forming a secondary air outlet through which the secondary air flows,
    When an imaginary line is extended linearly along the vertical direction from the axis of the nozzle,
    Let r be the distance between a first intersection where the virtual line intersects the circumference of the primary air outlet and the axis of the nozzle, and a second intersection of the circumferences of the secondary air outlet where the virtual line first intersects. Let d be the distance between the intersection point and the axis of the nozzle,
    satisfying 2 × r ≤ d,
    When viewed from the front, the ejection direction of the at least one main hole is oriented in a direction intersecting with the secondary air outlet.
    gas burner.
  13. 　前記ガスバーナは、炉に面する端面の形状が鉛直方向に沿って長手方向を有する矩形状の角型バーナである、
    　請求項１又は１２に記載のガスバーナ。     The gas burner is a rectangular burner whose end face facing the furnace has a longitudinal direction along the vertical direction.
    Gas burner according to claim 1 or 12.
  14. 　火炉と、
    　前記火炉に設けられる請求項１又は１２に記載のガスバーナと、を備える、
    　燃焼設備。     a furnace;
    and the gas burner according to claim 1 or 12 provided in the furnace,
    Combustion equipment.
PCT/JP2022/024296 2021-09-30 2022-06-17 Gas burner and combustion facility WO2023053605A1 (en)

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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5460742U (en) * 1977-10-07 1979-04-26
JPH0113207Y2 (en) * 1982-06-07 1989-04-18
JPH04155107A (en) * 1990-10-19 1992-05-28 Corona Kk Low nox burner
JPH0674816U (en) * 1993-03-02 1994-10-21 矢崎総業株式会社 Low NOx gas burner
JP2008111591A (en) * 2006-10-30 2008-05-15 Bab-Hitachi Industrial Co Gas burner
JP2010091244A (en) * 2008-09-09 2010-04-22 Mitsubishi Heavy Ind Ltd Pulverized coal burner and pulverized-coal-fired boiler having the pulverized coal burner
JP2010203746A (en) * 2009-03-06 2010-09-16 Chugai Ro Co Ltd Burner device and two-stage combustion type burner device
JP2020046098A (en) * 2018-09-18 2020-03-26 中外炉工業株式会社 Hydrogen gas combustion apparatus

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5460742U (en) * 1977-10-07 1979-04-26
JPH0113207Y2 (en) * 1982-06-07 1989-04-18
JPH04155107A (en) * 1990-10-19 1992-05-28 Corona Kk Low nox burner
JPH0674816U (en) * 1993-03-02 1994-10-21 矢崎総業株式会社 Low NOx gas burner
JP2008111591A (en) * 2006-10-30 2008-05-15 Bab-Hitachi Industrial Co Gas burner
JP2010091244A (en) * 2008-09-09 2010-04-22 Mitsubishi Heavy Ind Ltd Pulverized coal burner and pulverized-coal-fired boiler having the pulverized coal burner
JP2010203746A (en) * 2009-03-06 2010-09-16 Chugai Ro Co Ltd Burner device and two-stage combustion type burner device
JP2020046098A (en) * 2018-09-18 2020-03-26 中外炉工業株式会社 Hydrogen gas combustion apparatus

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