KR20200119878A - Burner device - Google Patents

Abstract

In the burner device (1) for supplying the premixed gas (M) of the fuel gas (F) and the supporting combustion gas (A) to the combustion region (R), the premixing passage (3) for premixing the fuel gas and the supporting combustion gas And, a porous burner head 7 made of sintered metal is provided for spraying the premixed gas M from the premixing passage 3 to the combustion region R, and the burner head 7 E, an inner layer 51 made of a sintered metal having a large particle diameter facing the premixing passage 3, and an outer layer made of a sintered metal having a smaller particle diameter than the inner layer 51 facing the combustion region R Install floor 53.

Description

Burner device

This application claims the priority of patent application 2018-028856 for which it applied on February 21, 2018, and the whole is cited as forming a part of this application by reference.

The present invention relates to a burner device that mixes and combusts fuel gas such as hydrogen gas and other types of gas.

In recent years, in order to suppress the emission of carbon dioxide, which causes environmental problems such as global warming, a burner device using hydrogen as a fuel has been proposed for the realization of a so-called low-carbon society (see, for example, Patent Document 1).

US Patent Application Publication No. 2012/0258409 Specification

However, when a fuel having a high combustion temperature is burned, NOx is likely to be generated. In addition, when a fuel having a high combustion rate is burned, a backfire phenomenon is likely to occur in which the flame generated in the combustion chamber returns to the burner side. Examples of the fuel having such a high combustion temperature and a high combustion rate include hydrogen or a gas containing hydrogen at a high concentration.

An object of the present invention is to provide a burner device capable of suppressing the generation of NOx and preventing the occurrence of backfire even when a fuel having a high combustion temperature and a high combustion rate is used.

In order to achieve the above object, the burner device according to the present invention,

A burner device for supplying a premixed gas of fuel gas and supporting combustion gas to a combustion region,

A premixing passage for premixing fuel gas and supporting combustion gas,

Porous burner head made of sintered metal for spraying into a combustion region by passing a premix gas from the premix passage

Including,

The burner head,

As an inner layer facing the premixing passage, an inner layer made of a sintered metal having a large particle diameter;

As an outer layer facing the combustion region, an outer layer made of a sintered metal having a smaller particle diameter than the inner layer

Have.

According to this configuration, the premixed gas is rectified by the inner layer having a large pore diameter by being formed of sintered metal particles having a large diameter, and a pressure loss occurs, thereby promoting the premixing. Further, when passing through an outer layer having a small pore diameter by being formed of sintered metal particles having a small particle diameter, the flow velocity of the premixed gas increases, and a high-speed premixed gas is injected into the combustion region. Accordingly, the generation of NOx can be suppressed, and backfire can be prevented.

In one embodiment of the present invention, at least a part of fuel gas supply pipes forming a fuel gas supply passage for supplying fuel gas to the premix passage may be provided inside the burner head. According to this configuration, the burner head can be cooled by the fuel gas flowing through the fuel gas supply pipe. Thereby, even when a backfire occurs or a flame is formed close to the burner, burnout of the burner head can be prevented.

In one embodiment of the present invention, the burner head forms a peripheral wall of the cylindrical burner device, and the fuel gas supply pipe includes a plurality of peripheral fuel gas supply pipes provided inside the burner head, The plurality of outer circumferential fuel gas supply pipes may extend in parallel in the axial direction of the burner device, and may be arranged at equal intervals in the circumferential direction of the burner head. According to this configuration, on the injection surface of the burner head, the premixed gas is kept at a low speed due to the presence of the fuel gas supply pipe between the high-speed regions of the premixed gas in which the fuel gas supply pipe does not exist. It is formed by this regular arrangement. Due to the presence of this flame retardant region, movement of the large flame in the circumferential direction in the high-speed region is restricted, and stable combustion as a whole burner head can be realized.

In one embodiment of the present invention, each outer circumferential fuel gas supply pipe has a fuel gas inlet on an upstream side of the burner head in the flow direction of the premixed gas, and the fuel gas supply pipe is on the axial center of the burner device. A central fuel gas supply pipe provided in the plurality of outer circumferential fuel gas supply pipes, the burner head communicates at a downstream end in the flow direction of the premixed gas, and is connected to the upstream side of the burner head. A central fuel gas supply pipe having a fuel gas outlet to the premix passage may be further included. According to this configuration, even when the outer circumferential fuel supply pipe is provided inside the cylindrical burner head, the complexity of the piping structure and the increase in the size of the burner device as a whole are suppressed.

Any combination of at least two configurations disclosed in the claims and/or in the specification and/or drawings are encompassed by the present invention. In particular, any combination of two or more in each claim of the claims is encompassed by the present invention.

The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are for mere illustration and description, and should not be used to define the scope of the present invention. The scope of the invention is defined by the appended claims. In the accompanying drawings, the same reference numerals in a plurality of drawings indicate the same or corresponding parts.
1 is a broken perspective view showing the schematic structure of a burner device according to an embodiment of the present invention.
Fig. 2 is a plan view showing an example of a fuel gas lead-out unit of the burner device of Fig. 1.
Fig. 3 is a plan view showing an example of a fuel gas lead-out portion of the burner device of Fig. 1.
Fig. 4 is a cross-sectional view showing an enlarged burner head of the burner device of Fig. 1.
Fig. 5 is a longitudinal sectional view schematically showing a schematic configuration of a burner device according to a modification of Fig. 1.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. 1 shows a burner device according to an embodiment of the present invention. The burner device 1 shown in the figure is a device that supplies a premixed gas M of fuel gas and auxiliary combustion gas to the combustion region R. The burner device 1 is used, for example, as a heating device for a power device such as a boiler or a gas turbine.

The fuel gas is, for example, a fuel having a high combustion temperature, a high combustion rate, and a wide range of combustible concentrations. In the present embodiment, a hydrogen-containing gas such as hydrogen gas is used as the fuel gas. In addition, in this embodiment, air (A) is used as a supporting combustion gas. As the assisting gas, in addition to air, for example, a gas whose oxygen concentration in the air is adjusted, exhaust gas, or the like can be used. In the following description, the fuel gas is referred to as "fuel (F)" and the supporting combustion gas is described as "air (A)".

The burner device 1 has a substantially cylindrical shape as a whole. The inner space of the burner device 1 forms a premixing passage 3 in which the fuel F and the air A are premixed. The burner device 1 faces the combustion region R and injects the premixed gas M into the combustion region R (the right part in Fig. 1), which is an injection unit 1a and a fuel F. ) And air (A) into the burner device 1 (a part on the left side of Fig. 1), which is a base 1b. The injection part 1a and the base 1b are arranged in the direction of the axial center C of the burner device 1. A flange 5 is provided at the boundary between the injection portion 1a and the base 1b of the burner device 1. The flange 5 serves as a connecting portion to a heating device in which the burner device 1 is used, and further partitions the combustion region R and a space for introducing the fuel F and/or the air A. In the following description, the combustion region R side (that is, the injection unit 1a side) in the axial direction of the burner device 1 is referred to as ``rear side'', and the side opposite to the combustion region (ie, the base (1b) side) is referred to as "front side". In this embodiment, the upstream side of the flow direction of the premixed gas M in the premixing passage 3 is the front side, and the downstream side is the rear side.

The burner head 7 that injects the premixed gas M into the combustion region R forms a peripheral wall of the injection portion 1a of the burner device 1. The premixed gas M of the premixing passage 3 passes through the burner head 7 in the radial direction and is injected into the combustion region R. An annular fuel introduction portion 9 is formed at the rear end of the base 1b, that is, a portion adjacent to the injection portion 1a via the flange 5. An outer circumferential fuel supply passage 11 extending parallel to the axial center C of the burner device 1 is formed from the inside of the fuel introduction part 9 to the inside of the burner head 7. Each outer circumferential fuel supply passage 11 is formed by an outer circumferential fuel supply pipe 13. In this example, a plurality of peripheral fuel supply pipes 13 are arranged at equal intervals in the circumferential direction of the burner device 1. A plurality of fuel introduction holes 15 extending in the radial direction are formed in the peripheral wall 9a of the fuel introduction part 9 to communicate the outer space of the fuel introduction part 9 with each outer fuel supply passage 11 Has been. Each fuel introduction hole 15 is a fuel inlet to the outer fuel supply passage 11, and through each fuel introduction hole 15, the fuel F from the outside of the burner device 1 is transferred to each outer fuel supply passage ( 11) is introduced.

One end of the burner device 1 which becomes the rear end of the injection part 1a is closed and formed in a state with a bottom. The inner space of the rear end of the injection unit 1a forms a common fuel header chamber 17 communicating with each of the outer circumferential fuel supply passages 11. In the central portion of the burner device 1, a common central fuel supply pipe 21 is provided in communication with the fuel header chamber 17 and forming a central fuel supply passage 19 extending along the axis C. The central fuel supply pipe 21 extends from the fuel header chamber 17 to the inner space of the base 1b. From the fuel lead-out section 23 located at the downstream end (front end) of the central fuel supply pipe 21, the fuel F is guided into the premix passage 3. In this way, in the illustrated example, the fuel supply passage 25 to the premix passage 3 is formed by the outer circumferential fuel supply passage 11, the fuel header chamber 17 and the central fuel supply passage 19. .

The other end of the burner device 1, which becomes the front end of the base 1b, is formed without a floor. The opening of the front end of the base 1b forms the air inlet 27. The air A introduced from the air inlet 27 joins the fuel F in the fuel lead-out portion 23 of the central fuel supply pipe 21.

In the illustrated example, a rectifying mechanism 29 is provided at the front end of the base 1b to rectify the flow of air A to a uniform flow along the axis C direction. Specifically, in this example, the rectifying mechanism 29 is provided in the opening of the air inlet 27, the split blade 31 and the split blade 31 equally dividing the inner space of the opening in the circumferential direction. ), and a plurality of (two in this example) annular rectifying perforated plates 33 installed downstream. Each of these elements constituting the rectifying mechanism 29 is provided on the outer periphery of the central post 35 extending forward from the central fuel supply pipe 21. However, the aspect of the rectifying mechanism 29 is not limited to this example. For example, only one of the split blades 31 and the rectifying porous plate 33 may be provided as the rectifying mechanism 33. In addition, the rectifying mechanism 29 may be omitted.

In the illustrated example, the fuel lead-out portion 23 of the central fuel supply pipe 21 is a pipe group of a plurality of (8 in this example) spoke-shaped pipes 39 projecting radially from the central fuel supply pipe 21. group) (41). As shown in FIG. 2, a fuel lead-out hole 43 serving as an outlet to the premix passage 3 of the fuel F is formed on the rear side of each spoke-shaped tube 39. As shown in FIG. In this example, a plurality of fuel lead-out holes 43 are arranged at equal intervals along the longitudinal direction of the spoke tube 39 in each spoke tube 39.

Moreover, the fuel lead-out part 23 of this example is provided with the pipe group 41 of two sets of spoke-shaped pipes 39. As schematically shown in Fig. 3, in the two sets of pipe groups, the positions in the circumferential direction of each spoke pipe 39A of the first pipe group 41A indicated by a solid line are adjacent spokes of the second pipe group 41B indicated by a broken line. It is arrange|positioned so that it may become a center circumferential position between the pipes 39B and 39B.

In addition, in the example shown in FIG. 1, a premixing promoting member promoting premixing of fuel F and air A on the downstream side (rear side) of the premixing passage 3 of the fuel lead-out unit 23 (45) is installed. More specifically, in this example, as the premixing promoting members 45, a plurality of (three in this example) annular premixed porous plates 45 are provided. Each premixed porous plate 45 is provided on the outer periphery of the central fuel supply pipe 21. In addition, the premixing promoting member 45 may be omitted.

However, in this embodiment, the structure for supplying each gas to the premixing passage 3 and the structure for promoting premixing in the premixing passage 3 are not limited to the above-described aspect.

Hereinafter, the structure of the burner head 7 in this embodiment will be described in detail. The burner head 7 is configured as a porous member made of sintered metal. Fine pores formed between the particles of the sintered metal form a flow path of the premixed gas M from the premixing passage 3 to the combustion region R.

Specifically, as shown in Fig. 4, the burner head 7 includes an inner layer 51 facing the premixing passage 3 (a layer indicated by crosshatching at large intervals in the drawing), and a combustion region ( It has an outer layer 53 (a layer indicated by crosshatching at small intervals in the figure) facing R). In the outer layer 53 and the inner layer 51, the particle diameters of the sintered metal particles forming each layer are different. That is, in this embodiment, the particle diameter of the sintered metal particles forming the outer layer 53 is smaller than the particle diameter of the sintered metal particles forming the inner layer 51.

The inner layer 51 has a large pore diameter, that is, a large flow path diameter, by being formed of sintered metal particles having a large particle diameter. The premixed gas M is rectified by the flow path of the inner layer 51, and the premixing is promoted. On the other hand, the outer layer 53 is formed of sintered metal particles having a smaller particle diameter than the inner layer 51, and thus has a smaller pore diameter, that is, a smaller flow path diameter than the inner layer 51. When passing through the flow path of the outer layer 53, the flow velocity of the premixed gas M increases, and the high-speed premixed gas M is injected into the combustion region R.

As the metal material used as the material of the sintered metal forming the burner head 7, for example, stainless steel, bronze, nickel, or the like can be used. In addition, the particle diameter (diameter) of the sintered metal particles forming the inner layer 51 is, for example, 500 to 1500 µm. The particle diameter of the sintered metal particles forming the outer layer 53 is, for example, 50 to 400 µm.

Further, as described above, an outer fuel supply pipe (fuel gas supply pipe) 13 is provided inside the burner head 7 to form the outer fuel supply passage 11. In the illustrated example, a plurality of peripheral fuel supply pipes 13 are arranged at equal intervals in the circumferential direction of the burner head 7. Further, the outer layer 53 and the inner layer 51 have substantially the same thickness (width in the radial direction). Each outer circumferential fuel supply pipe 13 is provided at the boundary between the outer layer 53 and the inner layer 51.

The burner head 7 is cooled by the fuel F flowing through the fuel supply pipe by providing the same fuel supply pipe as the outer fuel supply pipe 13 inside the burner head 7. Due to this cooling, burnout of the burner head 7 can be prevented even when a backfire phenomenon occurs or a flame is formed near the burner.

Further, since the outer fuel supply pipes 13 are arranged at equal intervals in the circumferential direction of the burner head 7, in the injection surface of the premixed gas M of the burner head 7, the outer fuel supply pipe ( 13) Between the high-speed regions HR of the premixed gas M in which there is no 13), the outer circumferential fuel supply pipe 13 is formed to form a storage region FR in which the premixed gas M becomes low speed in a regular arrangement. The presence of this flame retention region FR limits the movement of the large flame in the circumferential direction in the high-speed region HR, and a stable combustion is realized as a whole burner head 7.

In addition, in this embodiment, as described above, each of the outer circumferential fuel gas supply pipes 13 is the base 1b located on the upstream side (front side) of the burner head 7 in the flow direction of the premixed gas M. ), the central fuel supply pipe 21 communicates with the plurality of outer peripheral fuel supply pipes 13 at the downstream end (rear end) of the burner head 7 in the flow direction of the premixed gas M And a fuel outlet to the premix passage 3 on the upstream side of the burner head. By configuring in this way, even when the outer fuel supply pipe 13 is provided inside the cylindrical burner head 7, the complexity of the piping structure and the increase in the dimensions of the burner device 1 as a whole are suppressed.

However, the arrangement of the outer circumferential fuel supply pipe 13 and the central fuel supply pipe 21 inside the burner head 7 is not limited to this example. In addition, it is not essential to provide a fuel supply pipe such as the outer fuel supply pipe 13 inside the burner head 7.

Further, in this embodiment, an example in which the burner head 7 has a two-layer structure consisting of only the outer layer 53 and the inner layer 51 is presented, but the burner head 7 is not limited to such a two-layer structure. Does not. That is, the burner head 7 may have one or more intermediate layers made of sintered metal between the outer layer 53 and the inner layer 51. The intermediate layer in this case has, for example, a sintered metal particle diameter larger than the sintered metal particle diameter of the outer layer 53 and smaller than the sintered metal particle diameter of the inner layer.

In addition, the burner head 7 has an inner layer 51 made of a sintered metal having a larger particle diameter, and an outer layer 53 made of a sintered metal having a smaller particle diameter than the inner layer 51. If so, the shape is not limited to the cylindrical shape described above. The burner head 7 may have a flat plate shape, for example, as shown as a modified example in FIG. 5. In this example, at the downstream end of the premixing passage 3 of the burner device 1, a plate-shaped burner head 7 having a premixing spray surface orthogonal to the axial center C of the burner device 1 is mounted. . Further, in this case as well, although not illustrated, a fuel supply pipe may be provided inside the burner head 7.

According to the burner device 1 of Fig. 1 according to the present embodiment described above, the premixed gas M is rectified by the inner layer 51 having a large pore diameter by being formed of sintered metal particles having a large diameter, Premixing is promoted. In addition, when passing through the outer layer 53 having a small pore diameter by being formed of sintered metal particles having a small particle diameter, the flow velocity of the premixed gas M increases, and high-speed premixing in the combustion region R Gas (M) is injected. Accordingly, the generation of NOx can be suppressed, and backfire can be prevented.

In addition, the burner device 1 according to the present embodiment can be applied not only to the boiler device or gas turbine described above, but also to other types of power devices.

As described above, preferred embodiments have been described with reference to the drawings, but various additions, changes, or deletions may be made without departing from the spirit of the present invention. Accordingly, such things are also included within the scope of the present invention.

1: burner device
3: premix passage
7: burner head
11: Outer fuel supply passage (fuel gas supply passage)
13: Outer fuel supply pipe (fuel gas supply pipe)
19: central fuel supply passage (fuel gas supply passage)
21: external fuel supply pipe (fuel gas supply pipe)
25: fuel supply passage (fuel gas supply passage)
51: inner layer
53: outer layer
A: Air (assisting gas)
F: fuel (fuel gas)
M: premixed gas
R: combustion area

Claims (4)

A burner device for supplying a premixed gas of fuel gas and supporting combustion gas to a combustion region,
A premixing passage for premixing the fuel gas and the supporting combustion gas; And
A porous burner head made of a sintered metal for spraying into a combustion region by passing the premixed gas from the premixing passage;
Including,
The burner head,
As an inner layer facing the premixing passage, an inner layer made of a sintered metal having a large particle diameter;
As an outer layer facing the combustion region, an outer layer made of a sintered metal having a smaller particle diameter than the inner layer
Having,
Burner device. The method of claim 1,
A burner device, wherein at least a portion of a fuel gas supply pipe forming a fuel gas supply passage for supplying fuel gas to the premix passage is provided inside the burner head. The method of claim 2,
The burner head forms a peripheral wall of the cylindrical burner device, the fuel gas supply pipe includes a plurality of peripheral fuel gas supply pipes provided inside the burner head, and the plurality of peripheral fuel gas supply pipes, A burner device that extends in parallel in the axial direction of the burner device and is disposed at equal intervals in the circumferential direction of the burner head. The method of claim 3,
Each outer circumferential fuel gas supply pipe has a fuel gas inlet on the upstream side of the burner head in the flow direction of the premixed gas,
The fuel gas supply pipe is a central fuel gas supply pipe provided on an axial center of the burner device, and communicates with the plurality of outer fuel gas supply pipes at a downstream end of the burner head in the flow direction of the premixed gas ( And a central fuel gas supply pipe having a fuel gas outlet to the premix passage on the upstream side of the burner head.

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