JP5972925B2 - Burner device for mixed firing, gas nozzle, swirler and boiler - Google Patents

Description

The present invention relates to a mixed combustion burner device capable of simultaneously burning different fuels, for example, a liquid fuel such as heavy oil and a gas fuel such as natural gas, a gas nozzle used in the mixed combustion burner device, a swirler, and a mixed combustion burner device. It is about the boiler which incorporated .

  Conventionally, this type of mixed-burning burner apparatus has been employed in industrial and marine boilers. Patent Document 1 discloses this type of mixed burner apparatus. In the mixed combustion burner device disclosed in Patent Document 1, a flame holding swirler is arranged at the center of the burner, and an atomizer for atomizing and supplying liquid fuel such as heavy oil is installed on the central axis. . In addition, a plurality of pilot flame gas nozzles and main flame gas nozzles are respectively installed on the swirler blade portion and two virtual arrangement circles outside the swirler. Then, after the air is introduced into the wind box, it is guided through the register into the combustion chamber. At this time, as the air passes through the swirler, a vortex (recirculation region) is formed in the combustion chamber downstream of the swirler. The required flame is formed in the combustion chamber by being propagated to the fuel.

JP 2006-29763 A

  By the way, this kind of co-burning burner device is generally mounted in a large boiler and has a large combustion volume. Such a burner device is large and has a large number of parts. For this reason, it has been difficult to apply the mixed combustion burner device to a medium-sized boiler or a small-sized boiler. In addition, since such a medium-sized or small-sized boiler has a large combustion amount per unit volume of the combustion chamber, that is, a combustion chamber load, compared to a large boiler, it is difficult to achieve flame stability and compactness. Therefore, in a medium-sized or small-sized burner device, vibration combustion, incomplete combustion or the like is likely to occur.

  The burner device described in Patent Document 1 is capable of forming a stable flame and can cope with the downsizing of the boiler. However, both the main flame gas nozzle and the pilot flame gas nozzle are required as the flame gas nozzle. Therefore, the number of parts increases and the structure is complicated. In addition, since the gas nozzles for both flames are arranged on two different virtual arrangement circles in the register, the diameter of the burner device becomes large and there is a limit to downsizing.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a burner device for co-firing which can realize a stable flame formation, can be used for a medium-sized / small-sized boiler, and has a simple configuration.

  In order to achieve the above object, according to the present invention, a fuel nozzle disposed on the central axis of a register, a swirler disposed around the fuel nozzle, and a virtual arrangement centering on the fuel nozzle. In a mixed-burning burner apparatus comprising a plurality of gas nozzles arranged on a circle at mutually spaced intervals, the gas nozzle is directed toward a recirculation region formed by the swirler to form a pilot flame. A pilot flame gas opening through which gas fuel is injected and a main flame gas opening through which gas fuel is injected to form a main flame by the pilot flame are provided.

  In the above-described configuration, since one gas nozzle is provided with a pilot flame gas opening and a main flame gas opening, one gas nozzle has a function for forming a pilot flame and a main flame. Therefore, there is no need to provide two types of nozzles. For this reason, the number of parts of the burner device for mixed firing is reduced, and the device can be downsized.

  According to the present invention, the number of parts can be reduced to simplify the configuration, and the size can be reduced.

Sectional drawing of the burner apparatus for mixed combustion. Sectional drawing which shows the combustion chamber of the burner apparatus for mixed combustion. The perspective view of a swirler. The partially broken front view of a swirler part. The perspective view of the gas nozzle of an embodiment. Sectional drawing of the gas nozzle of embodiment. The front view of the gas nozzle of embodiment. (A)-(c) is a perspective view of a gas nozzle which shows a 1st modification, a cross-sectional view, and a longitudinal cross-sectional view. (A)-(c) is a perspective view of a gas nozzle which shows a 2nd modification, a cross-sectional view, and a longitudinal cross-sectional view. (A)-(d) is the perspective view of the gas nozzle which shows a 3rd modification, a top view, a cross-sectional view, and a longitudinal cross-sectional view. (A)-(i) is a perspective view, a right side view, a left side view, a plan view, a bottom view, a rear view, a front view of a gas nozzle showing a fourth modified example, a cross-sectional view taken along line AA in (b), BB sectional drawing of (g). (A)-(i) is a perspective view, a right side view, a left side view, a plan view, a bottom view, a rear view, a front view of a gas nozzle showing a fifth modification, and a cross-sectional view taken along line AA in (b). BB sectional drawing of (g). (A)-(j) is a perspective view, a right side view, a left side view, a plan view, a bottom view, a rear view, a front view of a gas nozzle showing a sixth modification, and a cross-sectional view taken along line AA in FIG. CC sectional view of (g), BB sectional view of (b). (A)-(j) are the perspective view of the gas nozzle which shows a 7th modification, a right side view, a left side view, a top view, a bottom view, a rear view, a front view, AA sectional view of (b), BB sectional drawing of (b), CDE sectional drawing of (g). A simplified diagram showing a boiler.

(Embodiment)
As shown in FIG. 1, a resistor 32 having a cone-shaped enlarged tip is projected from a front portion of an air box 31 that forms an outer shell of a mixed-burning burner device, and the inside of the expanded portion is a flame. It is a holding area 33. In this specification, the left side of FIG. An air receiving port 311 is formed at the rear end of the wind box 31. Then, air used for combustion is sent into the wind box 31 from a duct 34 of a blower device (not shown) connected to the air receiving port 311, and the air is supplied to the flame holding region 33 via the register 32. The

  As shown in FIG. 1, a cylindrical first stay 35 is fixed to the center of the wind box 31, and an atomizer 36 as a fuel nozzle located on the central axis of the register 32 is supported at the tip thereof. Yes. The atomizer 36 is supplied with liquid fuel through an oil supply pipe 38 and is supplied with a spray medium made of a pressure gas such as steam through an air supply pipe 37. As the liquid fuel, A heavy oil, B heavy oil, C heavy oil, kerosene, light oil, alcohol, biofuel and the like are used. Then, the liquid fuel ejected from the jet opening at the tip of the atomizer 36 is atomized by the pressure gas from the jet opening at the tip of the atomizer 36 and ejected to the center of the flame holding region 33. A cylindrical second stay 41 parallel to the first stay 35 is fixed to the outer peripheral side of the first stay 35, and an ignition burner nozzle 42 of an ignition burner is supported inside the tip. Liquid fuel is supplied to the ignition burner nozzle 42 via an oil supply pipe 43. The liquid fuel discharged from the ignition burner nozzle 42 is ignited by the spark of an igniter (not shown), and the flame is propagated to the fuel in the flame holding region 33. In this case, A heavy oil, light oil, kerosene or the like is used as the liquid fuel.

  As shown in FIGS. 1 to 3, a flame-holding swirler 51 is supported by a shaft cylinder 52 at the center of the front end of the first stay 35. A plurality of spiral blades 53 are fixed to the outer periphery of the shaft cylinder 52. A guide ring 54 located concentrically with the shaft cylinder 52 is fixed to the tip of the blade 53. Then, air from the rear side of the register 32 is guided by the guide ring 54 and passes between the blades 53, and a flame is formed in the flame holding region 33, thereby, as shown in FIG. A swirl flow around the central axis 100 of the flame holding region 33 of the atomizer 36 and the swirler 51 is formed in the inside 33. Further, as shown in FIG. 2, a recirculation region is formed in the flame holding region 33 in which the region of the central axis 100 is set to a negative pressure from the surroundings.

  As shown in FIG. 1, a gas fuel chamber 61 is defined at the rear end in the wind box 31. Gas fuel is supplied to the gas fuel chamber 61 through a supply pipe 62. As the gas fuel, liquefied natural gas, liquefied petroleum gas, low calorie gas or the like is used. A plurality of cylindrical five supply pipes 63 are connected to the gas fuel chamber 61. The supply pipe 63 is fixed to the inner surface of the wind box 31 by a bracket (not shown). The supply pipe 63 includes a connecting portion 64 on the rear end side, and a gas nozzle 65 detachably fixed to the front end of the connecting portion 64 with a screw. The gas nozzle 65 constitutes a gas burner. In the present embodiment, as shown in FIG. 4, the gas nozzles 65 are arranged on the virtual arrangement circle 101 centered on the central axis 100 at an equal pitch with a mutual interval. The front end surface 652 of the gas nozzle 65 is formed in a conical shape. The virtual arrangement circle 101 passes on the central axis 102 of the gas nozzle 65.

  As shown in FIGS. 1 and 3, one accommodating cylinder 55 is fixed inside the outer diameter position of the swirler 51, and the ignition burner nozzle 42 is accommodated therein. Concave portions 56 for accommodating the gas nozzles 65 are formed at a plurality of locations (five locations in the embodiment) at equal intervals of the guide ring 54. The gas nozzle 65 is accommodated in the recess 56 with a slight gap between the gas nozzle 65 and the inner peripheral surface of the recess 56. Therefore, the gas nozzle 65 is located inward in the radial direction of the swirler 51 from the outer diameter surface of the swirler 51. The tip of the ignition burner nozzle 42 is located behind the opening surface 511 at the front end of the swirler 51 in the housing cylinder 55. Further, the gas nozzle 65 has a tip protruding from the opening surface 511 toward the flame holding region 33.

  As shown in FIG. 5 to FIG. 7, one pilot flame gas opening (hereinafter referred to as a pilot opening) 66 that opens to the outer peripheral surface 651 is provided through the tip of the gas nozzle 65. When viewed from a direction parallel to the central axis 100 (hereinafter referred to as a front view), the pilot opening 66 is directed toward the center of the virtual arrangement circle 101 in the radial direction as shown in FIG. Accordingly, gas is ejected from the pilot opening 66 toward the central axis 100. The central angle θ1 of the pilot opening 66 with respect to the central axis 102 of the gas nozzle 65 is set within a range of minus 45 degrees to plus 45 degrees with respect to the radial line 103 of the virtual arrangement circle 101, and in this embodiment, 0 degrees. Is set to

  As shown in FIGS. 4 to 7, the gas nozzle 65 has a main flame gas first opening 67 (hereinafter, referred to as a first opening) 67 and a main flame gas second opening at the outer peripheral surface 651 at the tip of the gas nozzle 65. 68 (hereinafter referred to as a second opening). The first opening 67 has a central angle θ2 centered on the central axis 102 within a range of 15 to 90 degrees in the forward direction 104 of the swirl flow with respect to the radial line 103. In the present embodiment, the central angle θ2 is 36 degrees. For this reason, the first opening 67 is directed toward the center in the radial direction of the virtual arrangement circle 101 in the front view and is directed in the forward direction 104 of the swirl flow, and the gas is ejected in the direction of the first opening 67. Therefore, the first opening 67 is a virtual radius line 103 formed inward in the radial direction of the virtual arrangement circle 101 and a tangential direction of the virtual arrangement circle 101, and combustion air by the swirler 51, that is, a swirl flow The jet direction of the gas fuel through the first opening 67 is set within an angle range between the front direction 104 and a virtual tangent formed in the same direction.

  The second opening 68 has a central angle θ3 centered on the central axis 102 of the gas nozzle 65 with respect to the radius line 103 within a range of 90 ° to 180 °. In the present embodiment, the central angle θ3 is 108 degrees. Accordingly, the second opening 68 is directed in the forward direction 104 of the swirl flow in the opposite direction to the radial direction of the virtual arrangement circle 101 in a front view, and gas is ejected in the direction of the second opening 68. That is, a virtual radius line 103 formed radially outward of the virtual arrangement circle 101 by the second opening 68, and a combustion air by the swirler 51 in the tangential direction of the virtual arrangement circle 101, that is, a swirl flow The jet direction of the gas fuel through the second opening 68 is set within an angle range between the forward direction 104 and the virtual tangent formed in the same direction.

  As shown in FIG. 5, the pilot opening 66, the first opening 67, and the second opening 68 are formed at the same position in the axial direction of the gas nozzle 65 and have a radial direction centered on the central axis 102 of the gas nozzle 65. They are oriented, and they have the same diameter. As shown in FIG. 2, the pilot opening 66, the first opening 67, the second opening 68, and the third opening 69 are located in front of the front end opening surface 511 of the swirler 51.

  As shown in FIGS. 5 to 7, a gas flame 65 has a main flame gas third opening (hereinafter, referred to as a third opening) 69 that is open to the tip surface 652 of the gas nozzle 65. The third opening 69 has a central angle θ4 in the range of plus 45 degrees to minus 45 degrees on the outward radial line side with the center axis 102 as the center. In this embodiment, θ4 is 0 degrees. Accordingly, the third opening 69 is directed outward in the radial direction of the virtual arrangement circle 101 in a front view, that is, the virtual arrangement of the gas nozzle 65 from the tip of the gas nozzle 65 by the third opening 69. Gas is ejected in the radially outward direction of the circle 101.

  Then, approximately 40 percent of the total amount of all gas fuel ejected from the gas nozzle 65 is ejected from the third opening 69, and approximately 20 percent is ejected from the pilot opening 66, first and second openings 67, 68, respectively. The inner diameters of the openings 66 to 69 are set.

  As shown in FIG. 2, the pilot opening 66, the first opening 67, and the second opening 68 are directed to the downstream side of the recirculation region, to the inside, and parallel to the central axis 100, respectively, as viewed from the side. Inclined with respect to the axis 105. The inclination angle of the openings 66, 67, 68 with respect to the axis 105 is the largest in the pilot opening 66 and decreases in the order of the first opening 67 and the second opening 68. The third opening 69 is directed toward the downstream direction of the recirculation region, directed outward, and inclined with respect to the axis 105 parallel to the central axis 100.

As shown in FIG. 15, the mixed-burning burner device 30 configured as described above is installed and operated in the casing of the boiler 80.
Next, the operation of the burner device for mixed combustion of this embodiment will be described.

  By operation of a blower (not shown), air is introduced into the wind box 31 from the air receiving port 311 at the rear end of the wind box 31. The air passes through the register 32 through the swirler 51, flows as a swirl swirl around the axis 100 into the flame holding region 33 from the front end opening surface 511 of the swirler 51, and from the outside toward the central axis 100 side. It becomes the recirculation flow that flows. At this time, liquid fuel is sprayed from the atomizer 36 into the flame holding region 33 along the direction of the central axis 100, the ignition burner nozzle 42, the pilot opening 66 of the gas nozzle 65 and the first to third openings 67 to 69. Gas fuel is ejected from At the same time, the liquid burner is ignited by the igniter in the ignition burner nozzle 42. Then, the flame is propagated to the fuel from the atomizer 36 and the gas nozzle 65.

  At this time, a flame is formed in the recirculation flow with swirling by the swirler 51 at the center of the flame holding region 33, and the fuel ejected from the atomizer 36 and the gas nozzle 65 is stably burned by this flame. be able to. That is, the air passing from the register 32 through the swirler 51 is swung in one direction by the swirling blades of the swirler 51, thereby forming a recirculation region. For this reason, mixing of the air and the fuel ejected from the atomizer 36 and the gas nozzle 65 is promoted, and a stable flame is formed. In the flame holding region 33, after the flame by the fuel from the atomizer 36 and the gas nozzle 65 is stabilized, the supply of the liquid fuel from the ignition burner nozzle 42 is stopped. Thus, after the flame from the fuel from the atomizer 36 or the gas nozzle 65 is stabilized, the operation of the ignition burner is stopped. However, when the flame is unstable, the ignition burner can be operated, or can be always operated. In particular, when a fuel with a small calorific value is used, the ignition burner may be always operated. The ignition burner uses liquid fuel in this embodiment, but it is also possible to use gas fuel.

  Since the atomizer 36 is provided on the central axis 100 of the flame holding region 33 and the gas nozzle 65 is provided around the atomizer 36, the mixed combustion burner device 30 according to the present embodiment can simultaneously burn oil and gas. It can be used not only for use but also for oil-only and gas-only use. In this case, an oil flame or a gas flame is sufficiently retained in the recirculation region, which is a negative pressure region formed by the swirler 51, and a stable flame is formed. Therefore, with oil and gas fuel, a high turndown ratio operation is possible in the exclusive combustion operation and the mixed combustion operation, and a compact and stable flame can be formed.

And in this embodiment, the following operations and effects can be obtained.
(1) The gas nozzle 65 is provided with a pilot opening 66 through which gas fuel is injected toward the recirculation region formed by the swirler 51, and a pilot flame is formed by the gas fuel injected from the pilot opening 66. The The gas nozzle 65 is provided with first to third openings 67 to 69 into which gas fuel for forming a main flame is formed based on the pilot flame. Accordingly, unlike the conventional configuration, it is not necessary to separately provide a pilot gas nozzle and a main gas nozzle that supply gas fuel for pilot flame, and the configuration is simplified by reducing the number of parts and the device by reducing the diameter of the swirler 51. Can be reduced in size.

  (2) The jet direction of the gas fuel from the pilot opening 66 is set to be within a range of minus 45 degrees to plus 45 degrees in the radial direction center of the virtual arrangement circle 101 of the gas nozzle 65. According to this configuration, by supplying an appropriate amount of gas from the pilot opening 66 to the recirculation region formed by the swirler 51, a compact and stable pilot gas flame can be formed. Therefore, as described above, it is possible to contribute to the miniaturization of the entire mixed combustion burner device and to obtain a low vibration mixed combustion burner device.

(3) In particular, the jet direction of the gas fuel from the pilot opening 66 is set to be the center of the virtual arrangement circle 101 in the radial direction. According to this configuration, an appropriate amount of gas can be supplied from the pilot opening 66 to the recirculation region formed by the swirler 51, and a stable pilot gas flame can be formed. In particular, this effect is significant in the gas-only firing operation. The pilot opening 66 ejects gas toward a position downstream of the opening surface 511 of the swirler 51 on the flame holding region 33 side. If it does in this way, the gas fuel injected from the gas injection opening part will mix moderately with respect to the negative pressure area | region formed in the downstream part of the swirler 51, and the stable gas flame will be formed. Further, the pilot gas opening 66 is inclined toward the central axis side with respect to the downstream side in the axial direction. In this way, since the gas jet is wound inward from the outer periphery of the circulation region, the gas fuel is suitably mixed into the circulation region without destroying the circulation flow, and a stable flame is formed.

  (4) In the side view shown in FIG. 2, the pilot opening 66 is directed forward and inwardly and recirculated from a position in front of the opening surface 511 of the combustion air outlet of the swirler 51. Gas was ejected toward the downstream position of the flow. For this reason, the gas fuel ejected from the pilot opening 66 is appropriately supplied to the recirculation region formed in the downstream portion of the swirler 51 or the vicinity thereof, and a stable gas flame is formed.

  (5) As described above, in a side view, the directivity angle of the pilot opening 66 is tilted forward and inward at a position in front of the opening surface 511 of the swirler 51 to a position downstream of the recirculation region. It opened so that gas might spout out. For this reason, the gas jet from the pilot opening 66 is wound inward from the outer periphery of the recirculation region, and the gas fuel is suitably mixed into the recirculation region. For this reason, a recirculation flow is not destroyed and a compact and stable flame is formed. On the other hand, in a side view, when the gas ejection direction from the pilot opening is made substantially inwardly perpendicular to the central axis 100, the gas jet passes through the recirculation region, and a part of this circulation flow is divided. Destroyed. In such a case, flame stability is hindered and the flame is likely to become unstable. In the present embodiment, occurrence of such a problem can be suppressed.

  (6) The front end of the gas nozzle 65 protrudes from the opening surface 511 toward the flame holding region 33. Therefore, as is apparent from FIG. 2, the pilot opening 66 and the first to third openings 67, 68, 69 are easily provided at an effective position for facilitating the gas fuel to enter the recirculation region from the outer peripheral side thereof. Can be arranged. Therefore, it can contribute to the formation of a compact and stable flame.

  (7) Since the pilot opening 66 is opened on the outer peripheral surface 651 of the gas nozzle 65, it is easy to direct the pilot opening 66 in an inclined state toward the downstream in the direction of the central axis 100 in order to stabilize the flame. Effective and easy contribution to the formation of a compact and stable flame.

  (8) A radial line formed inward in the radial direction of the virtual arrangement circle 101 of the gas nozzle 65 by the first opening 67 and a tangential direction of the virtual arrangement circle 101, and the combustion air generated by the swirler 51. The gas fuel ejection direction is set within an angular range between a virtual tangent formed in the same direction as the turning direction. According to this configuration, an appropriate amount of gas can be supplied from the first opening 67 to the recirculation region formed by the swirler 51, and an appropriate amount of gas can be supplied around the pilot gas flame. Without extending, it is possible to form a stable pilot gas flame in a compact form.

  (9) The second opening 68 is the same as the virtual radial line formed outward in the radial direction of the virtual arrangement circle 101 and the tangential direction of the virtual arrangement circle 101 and the swirling direction of the combustion air by the swirler 51 It is oriented within the angular range between the virtual tangent formed in the direction. Accordingly, gas is supplied from the second opening 68 toward the recirculation region so as to surround the gas ejection region from the first opening 67. For this reason, it is possible to form a main flame that is compact and stable in the same manner as described above.

  (10) The third opening 69 is opened at the tip of the gas nozzle 65 outward in the radial direction of the virtual arrangement circle 101 of the gas nozzle 65 and in the direction of the recirculation region in a side view. Accordingly, gas is supplied to the air flow outside the swirler 51 to form a flame surrounding the outside of the recirculation region. For this reason, the whole flame holding area | region 33 can be utilized effectively, and the flame which was united can be formed. Therefore, a compact flame can be formed with high efficiency, and a burner device for co-firing that can be operated with high efficiency can be realized without increasing the size.

  (11) The gas nozzle 65 is positioned so as to cut into the center side of the outer shape of the swirler 51. Therefore, it becomes easy to mix the pilot gas into the recirculation region formed on the front surface of the swirler. In addition, the outer shape of the burner device for co-firing is reduced, and the size can be reduced.

(Modification example of gas nozzle 65)
By the way, since the gas nozzle 65 can be variously changed, several examples will be listed below.

  8A to 8C, 9A to 9C, and 11A to 11I, the pilot opening 66, the first opening 67, the second opening 68, and the third opening are illustrated. The arrangement interval 69 is displaced in the circumferential direction of the gas nozzle 65. Here, the pilot opening 66 is disposed within the central angle θ1 of FIG. 7 and the third opening 69 is re-oriented so that the first and second openings 67 and 68 are directed in front of the swirl flow. The gas nozzle 65 is disposed on the outer periphery of the swirler 51 so as to be directed in front of the circulating flow.

  In the examples of FIGS. 10A to 10D and FIGS. 14A to 14J, the tip surface 652 of the gas nozzle 65 is made spherical. In this way, vortices such as Karman vortices starting from the tip of the gas nozzle 65 can be reduced, and the frequency of occurrence can be reduced. Therefore, the combustion efficiency can be improved.

In the examples of FIGS. 11A to 11I, the tip surface of the gas nozzle 65 is made flat. In this way, the outer shape of the gas nozzle 65 can be easily processed.
In the example of FIGS. 12A to 12I, the pilot opening 66 and the first and second openings 67 and 68 are formed on the tip surface of the gas nozzle 65. Note that one or two of the pilot opening 66 and the first and second openings 67 and 68 may be formed on the front end surface of the gas nozzle 65.

  The two-dot chain line in FIG. 2, FIGS. 10 (a) to (d), FIGS. 13 (a) to (j), and FIGS. 14 (a) to (j) are shown in the pilot opening 66 and the first and second openings 67. , 68 is formed at a position on the base end side of the gas nozzle 65 so as to be located on the opening surface 511 of the swirler 51 or on the upstream side of the opening surface 511. Even if comprised in this way, gaseous fuel will flow to the outer peripheral side of a recirculation area | region, and will be wound in the inside of the area | region. In this case, if the pilot opening 66 and the first and second openings 67 and 68 positioned on the upstream side of the opening surface 511 are positioned on the inner peripheral surface side of the concave portion 56, the gas fuel from the gas nozzle 65 is discharged. It is preferably caught in the recirculation zone.

(Other changes)
In addition, this invention is not limited to the said embodiment, You may actualize with the following changes.

  -In the said embodiment, the gas nozzle 65 is formed in the cylindrical shape, and the cross-sectional shape is formed circularly. However, the present invention is not limited to this, and the gas nozzle 65 may have a rectangular tube shape so that the gas nozzle 65 is formed in a polygonal shape such as a pentagon, hexagon, or octagon.

  In the embodiment, the recess 56 is formed on the outer periphery of the swirler 51, and the gas nozzle 65 is disposed on the center side in the radial direction from the outer diameter position of the swirler 51. The position in the radial direction of the swirler 51 of the gas nozzle 65 may be displaced so as to be closer to the center than in the above embodiment, and as shown by a two-dot chain line in FIG. The blade 53 of the swirler 51 may be penetrated. Alternatively, the arc of the concave portion 56 may be shallowed so as to be displaced to the outer diameter side of the swirler 51 from the above-described embodiment, or may be disposed outward from the outer diameter position of the swirler 51.

  The atomizer 36 is a steam spray type, but may be a two-fluid injection atomizer such as an air spray atomizer. Further, a pressure spray type atomizer that does not use an atomizing medium may be used.

  In place of the atomizer 36, a gas nozzle as a fuel nozzle may be provided at the center of the swirler 51. In this case, the gas ejected from the gas nozzle and the gas ejected from each gas nozzle 65 may be the same type of gas or different types of gas. When the same type of gas is used, the burner device becomes a gas burner device for exclusive use of gas, and when different types of gas are used, it becomes a burner device for mixed combustion of different gases.

The number of gas nozzles 65 is not limited to five. Any number of 2-4, 6 or more is possible. In this case, the gas nozzles 65 are preferably arranged at equal intervals.
A plurality of pilot flame gas openings may be provided so as to be located within the central angle θ1.

-You may change the number of gas openings for main flames to 1, 2 or 4 or more.
-In the said embodiment, although the mixed-burning burner apparatus 30 is actualized for boilers 80, it can utilize for other uses, such as not only for this but for an industrial furnace and a hot-air generator.

  In the above-described embodiment, the tip of the gas nozzle 65 is protruded from the opening surface 511 of the swirler 51 toward the flame holding region 33. However, the gas nozzle 65 may not be protruded. Even in this configuration, since the gas nozzle 65 is located on the outer periphery of the swirler 51, the pilot opening 66 and the first to third openings 67, 68, 69 can be arranged.

  In the embodiment, the pilot opening 66, the first and second openings 67, 68 have the same diameter. However, the diameters of the openings 66, 67, 68 and the third opening 69 may vary depending on various conditions, for example, It is appropriately set according to conditions such as the ratio of the amount of air passing through the inside of the swirler 51 and the amount of air passing through the outside of the swirler 51, the swirling strength of the swirl flow, and the like. Therefore, the ratio of the amount of gas fuel ejected from each opening 66, 67, 68, 69 is also set appropriately according to various conditions.

  30 ... Mixed burner device, 32 ... Register, 33 ... Flame holding area, 36 ... Atomizer, 51 ... Swirler, 511 ... Opening surface, 56 ... Recess, 65 ... Gas nozzle, 66 ... Gas opening for pilot flame, 67 ... Main flame Gas first opening, 68 ... Main flame gas second opening, 69 ... Main flame gas third opening, 100 ... Center axis, 101 ... Virtual arrangement circle

Claims (10)

A fuel nozzle disposed on the central axis of the register;
A swirler disposed around the fuel nozzle;
In a mixed combustion burner device comprising a plurality of gas nozzles arranged at intervals on a virtual arrangement circle centered on the fuel nozzle,
In the gas nozzle,
A pilot flame gas opening through which gas fuel is injected towards a recirculation zone formed by the swirler to form a pilot flame;
In order to form a main flame by the pilot flame, a gas opening for main flame into which gas fuel is injected is provided ,
The pilot flame gas is formed so that the pilot flame gas opening is opened in the outer peripheral surface of the gas nozzle, and the gas fuel is ejected from the pilot flame gas opening in the radial direction of the virtual arrangement circle. Set the direction of the aperture,
The main flame gas opening includes a main flame gas opening that opens to the outer peripheral surface of the tip of the gas nozzle, and a main flame gas that opens to the tip surface of the tip of the gas nozzle in the radially outward direction of the virtual circle. A burner device for co-firing composed of an opening . 2. The co-firing according to claim 1 , wherein an inner diameter of a main flame gas opening opened at a distal end surface of the distal end portion of the gas nozzle is set larger than an inner diameter of a main flame gas opening opened at an outer peripheral surface of the distal end portion . Burner device. The co-firing according to claim 1, wherein the pilot flame gas opening is located on the base end side of the outer peripheral surface of the gas nozzle, and gas is ejected toward a position downstream from the opening surface on the flame holding region side of the swirler. Burner equipment. The mixed combustion burner device according to claim 3 , wherein the pilot flame gas opening is inclined toward the central axis side with respect to the downstream side in the axial direction. The main flame gas opening that opens to the outer peripheral surface of the distal end portion of the gas nozzle, the virtual distribution inward radial line of設円, a tangent of the virtual distribution設円, the turning direction of the combustion air by swirler The co-firing burner device according to any one of claims 1 to 4 , wherein a gas fuel ejection direction is set within an angular range between virtual tangents in the same direction. The gas opening for the main flame that opens to the outer peripheral surface of the tip of the gas nozzle ,
A virtual radial line formed radially outwardly of the virtual distribution設円, between the virtual tangent line which is formed in the same direction as the turning direction of the combustion air by the swirler said a tangential direction of the virtual distribution設円The burner device for co-firing according to any one of claims 1 to 4 , wherein the jet direction of the gas fuel is set within the angle range. The burner device for co-firing according to any one of claims 1 to 6 , wherein a concave portion that is located closer to the swirler center than the outer diameter is formed in the swirler, and a gas nozzle is disposed in the concave portion. Gas nozzle according to any one of claims 1-7. The swirler according to any one of claims 1 to 7 . A boiler in which the burner device for mixed combustion according to any one of claims 1 to 7 is incorporated in a boiler casing.