CN107246611B

CN107246611B - Gas burner

Info

Publication number: CN107246611B
Application number: CN201710677337.XA
Authority: CN
Inventors: 李宇; 张世程; 苏毅; 闫玉强; 沈玲玲; 梁健; 邬文燕; 曾磊赟; 张静
Original assignee: Shanghai Qiyao Thermal Energy Engineering Co ltd; 711th Research Institute of CSIC
Current assignee: Shanghai Qiyao Thermal Energy Engineering Co ltd; 711th Research Institute of CSIC
Priority date: 2017-08-09
Filing date: 2017-08-09
Publication date: 2024-03-22
Anticipated expiration: 2037-08-09
Also published as: WO2019029062A1; CN107246611A

Abstract

The invention provides a gas burner. It includes body, flue gas passageway, first fuel injection device and side direction fuel injection device. The body has a sidewall extending in an axial direction, the sidewall enclosing a cavity. The flue gas channel is disposed at one end of the body and has a first inlet and a first outlet. The first inlet is directed laterally of the body. The first outlet is directed axially outward of the body. And the cross-sectional area of the flue gas channel at the first inlet is larger than the cross-sectional area at the first outlet. A first fuel injection device is disposed in the cavity and extends into the flue gas channel. The first fuel injection device includes a first nozzle. The injection end of the first nozzle is positioned in the flue gas channel. The lateral fuel injection device includes a lateral nozzle. The lateral nozzle faces laterally of the body. The gas burner can effectively realize low-nitrogen combustion and can stably burn in a wide load range.

Description

Gas burner

Technical Field

The invention relates to the field of combustion equipment, in particular to a gas burner.

Background

With the continuous deepening and implementation of environmental protection concepts in the industry, the global restrictions on the emissions of combustion pollutants of fossil fuels are imposed. In the field of gas combustion, national and local standards are very strictly limited on pollutant discharge amounts of various gas combustion devices according to different geographic areas, industries and industrial application devices. The low emission capability of nitrogen oxides is one of the most important technical indicators for measuring combustion equipment.

In the combustion of fuel, the main sources of nitrogen oxides are of three types: fuel-type NOx, thermal-type NOx, and rapid-type NOx. For coal-based fuels, fuel-type NOx is the most dominant source, while for gaseous fuels with few nitrogen-containing components, the main sources of nitrogen oxides are thermal NOx and rapid NOx due to their faster combustion rate, higher fuel heating value, and higher flue gas temperature.

In the field of gas combustion, low-nitrogen gas combustion technologies mainly have two main categories: (1) a low nitrogen gas burner; (2) a low-nitrogen combustion control technology in a hearth. In the field of today's industrial technology, two major types of emission abatement measures are often used in combination to achieve higher low nitrogen emissions performance.

According to the industrial practice experience, the existing low-nitrogen gas burner has the following problems: (1) combustion instability over a wide load range; (2) low nitrogen rejection capability instability over a wide load range; (3) combustor combustion mode is single, etc.

Accordingly, there is a need to provide a gas burner that at least partially solves the problems of the prior art.

Disclosure of Invention

In the summary, a series of concepts in simplified form are introduced, which will be further described in detail in the detailed description. The summary of the invention is not intended to define the key features and essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

To at least partially solve the above problems, the present invention provides a gas burner comprising:

a body having a sidewall extending in an axial direction, the sidewall enclosing a cavity;

a smoke passage disposed at one end of the body, the smoke passage having a first inlet and a first outlet, the first inlet facing laterally of the body, the first outlet facing axially outward of the body, and a cross-sectional area of the smoke passage at the first inlet being greater than a cross-sectional area of the smoke passage at the first outlet;

a first fuel injection device disposed in the cavity and extending into the flue gas channel, the first fuel injection device comprising a first nozzle having an injection end located within the flue gas channel; and

a lateral fuel injection device comprising a lateral nozzle oriented laterally of the body.

According to the above technical scheme, set up the flue gas passageway in the one end of combustor body, the cross sectional area of flue gas passageway in the entrance is greater than the cross sectional area of exit to the combustor still includes first fuel injection device and side direction fuel injection device. Therefore, the first fuel injection device can inject high-speed fuel gas and entrain a large amount of hearth flue gas in the flue gas channel, so that negative pressure is formed in the flue gas channel, the pressure in the hearth is larger than the pressure in the flue gas channel, and high-temperature hearth flue gas around the fuel gas burner is continuously injected into the flue gas channel under the action of the pressure, so that a flue gas internal circulation channel is formed. By arranging the lateral fuel injection device, fresh high-temperature flue gas generated by lateral flame is always distributed in the lateral range of the end part of the gas burner, and the flue gas enters a flue gas channel along with the flue gas of the hearth and is fully mixed with fuel gas sprayed out by the first fuel injection device. Due to high-speed fuel gas, high-temperature furnace flue gas and high-temperature flue gas generated by lateral flameThe fuel has the characteristics of oxygen deficiency and fuel enrichment, so that the combustion is slow, and the emission of NOx, particularly thermal NOx, can be reduced. In addition, because a certain amount of nitrogen-containing chemical intermediate substances are generated after the combustion of the fuel gas injected by the lateral fuel injection device, NO is facilitated _X Can further reduce NOx emissions. And the lateral fuel injection device can split partial fuel gas, so that the combustion of the partial fuel gas occurs in the lateral direction of the end part of the fuel gas burner, the combustion load of the first fuel injection device of the fuel gas burner is reduced, and the generation of thermal NOx is reduced. In addition, because the high-temperature furnace flue gas sucked into the flue gas channel and the high-temperature flue gas generated by lateral flame have higher temperature, the gas at the first nozzle can be stabilized to catch fire, and the combustion can be stabilized in a wide load range.

Preferably, the cross-sectional area of the flue gas channel decreases gradually from the first inlet to the first outlet. Therefore, the flue gas channel is constructed as a tapered channel, and plays a role in accelerating rectification of combustion-supporting gas.

Preferably, the first inlet is closer to the body than the first outlet in the axial direction.

Preferably, the lateral flow guide plate is arranged at the lateral nozzle for guiding combustion supporting gas to the lateral nozzle.

Preferably, the lateral baffle comprises a first portion arranged in the cavity and extending substantially in the axial direction, and a second portion connected to the first portion and extending at an angle to the radial direction, the angle being between 0 ° and 30 °.

Preferably, the flue gas channel is formed by a flue gas channel member comprising an arcuate outer plate, an arcuate inner plate and axial deflectors connected to both sides of the outer and inner plates, wherein the first fuel injection device passes through the inner plate.

Preferably, the ends of the inner and outer plates forming the first outlet are in the same plane parallel to the radial direction of the body, both forming part of concentric rings.

Preferably, the radius of the end of the inner side plate forming the first outlet is smaller than the radius of the cavity, and the radius of the end of the inner side plate forming the first inlet is larger than the radius of the cavity.

Preferably, the radius of the end of the inner side plate forming the first inlet is equal to the radius of the end of the outer side plate forming the first inlet.

Preferably, the axial baffle extends into the cavity in an axial direction and extends in a radial direction, the lateral baffle being mounted to the axial baffle.

Preferably, the lateral baffle is mounted to the axial baffle positionally adjustable along the axial direction.

Preferably, the axial deflector extends in a radial direction to the inner surface of the side wall, the axial deflector having an inclined end within the cavity, the inclined end increasing in size in the axial direction in a radially outward direction.

Preferably, the lateral nozzle of the lateral fuel injection device is configured such that the jet cone angle of the injected jet is 0 ° to 120 °.

Preferably, the first nozzle is directed toward the outside of the body in the axial direction, and the injection end of the first nozzle is closer to the body than the first outlet in the axial direction.

Preferably, the gas burner further includes an auxiliary fuel injection device facing outward in the axial direction, an injection speed of the fuel gas in the auxiliary fuel injection device being smaller than an injection speed of the fuel gas in the first fuel injection device.

Preferably, the gas burner further comprises a gas delivery main pipe; the first fuel injection device comprises a first fuel gas delivery pipe communicated with the fuel gas delivery main pipe, the lateral fuel injection device comprises a second fuel gas delivery pipe communicated with the fuel gas delivery main pipe, and the second fuel gas delivery pipe communicates the auxiliary fuel injection device with the fuel gas delivery main pipe; the gas burner further includes a regulator valve disposed on one of the first gas delivery conduit and the second gas delivery conduit.

Preferably, the gas burner comprises a plurality of flue gas channels and a plurality of lateral fuel injection devices, wherein the flue gas channels are arranged at intervals along the circumferential direction of the body, and the lateral fuel injection devices are positioned between two adjacent flue gas channels.

Preferably, a plurality of the first fuel injection devices are arranged in each flue gas channel.

Preferably, the cross-sectional area of the flue gas channel is smallest at the first outlet.

Drawings

The following drawings of embodiments of the present invention are included as part of the invention. The drawings illustrate embodiments of the invention and their description to explain the principles of the invention. In the drawings of which there are shown,

FIG. 1 is a schematic perspective view of a gas burner according to a preferred embodiment of the present invention, wherein a combustion mode of the gas burner is shown;

FIG. 2 is a schematic cross-sectional view of the gas burner of FIG. 1;

FIG. 3 is a schematic perspective view of an end of the gas burner of FIG. 1; and

fig. 4 is an end section schematic view of the gas burner of fig. 3.

Reference numerals illustrate:

gas burner 10

Side wall 21 of body 20

Cavity 22 lateral baffle 23

Gas delivery main pipe 25 of regulating valve 24

First portion 231 second portion 232

First inlet 31 of flue gas channel 30

First outlet 32 flue gas channel member 40

An inner plate 42 of the outer plate 41

First fuel injection device 50 of axial deflector 43

First nozzle 51 first gas delivery pipe 52

High velocity flame 53 side fuel injection device 60

The lateral nozzle 61 is provided with a second gas delivery pipe 62

Side flame 63 assisted fuel injection device 70

Auxiliary nozzle 71 third gas delivery conduit 72

Auxiliary flame 73 flame stabilizing cover 74

Combustion-supporting gas b of gas a

High-temperature hearth flue gas c lateral combustion-supporting gas b1

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that embodiments of the invention may be practiced without one or more of these details. In other instances, well-known features have not been described in detail in order to avoid obscuring embodiments of the invention.

In the following description, a detailed structure will be presented for a thorough understanding of embodiments of the present invention. It will be apparent that embodiments of the invention may be practiced without limitation to the specific details that are set forth by those skilled in the art.

Fig. 1-4 illustrate a gas burner 10 according to a preferred embodiment of the present invention. The gas burner 10 may be used in a boiler, for example. As shown in fig. 1-4, the gas burner 10 may generally include a body 20, a flue gas channel 30, a first fuel injection device 50, and a side fuel injection device 60. The gas burner 10 of the present invention and its various components will be described in detail below in conjunction with fig. 1-4.

As shown in fig. 1 and 2, in the present embodiment, the body 20 of the gas burner 10 may be cylindrical with a sidewall 21 extending in the axial direction and circumferentially surrounding a cavity 22 extending in the axial direction. Specifically, in the present embodiment, when the gas burner 10 is installed as shown in fig. 2, the "axial direction" refers to the vertical direction, and the "radial direction" to be mentioned hereinafter refers to the horizontal direction perpendicular to the axial direction. The shape of the body 20 is not limited to the cylindrical shape shown in fig. 1-4. In other embodiments, the body 20 may be any other suitable shape. For example, the body 20 may be a thin-walled structure having a cavity with a rectangular, oval or other shape in cross-section.

In order to enable the internal circulation of the flue gas of the gas burner 10, a flue gas channel 30 is provided at one end of the body 20, and the opposite end of the body 20 may be an inlet for the combustion gas b, i.e. the cavity 22 is filled with the combustion gas b. In the present preferred embodiment, one end of the body 20 may be provided with three smoke passages 30, and the three smoke passages 30 are disposed at equal intervals along the circumferential direction of the body 20. One skilled in the art will appreciate that one or any other suitable number of the plurality of flue gas channels 30 may be provided as desired. Where a plurality of flue gas passages 30 are provided, the plurality of flue gas passages 30 may be provided at unequal intervals.

As shown in fig. 3, the flue gas channel 30 has a first inlet 31 and a first outlet 32. The first inlet 31 faces laterally of the body 20. Preferably, the first inlet 31 may face laterally of the body 20 and be disposed outside the body 20. It should be noted that "lateral" as referred to herein refers to a direction substantially parallel to the radial direction and toward the outside of the body 20. That is, it may be strictly parallel to the radial direction, or may be at a small angle, e.g., 0 ° to 30 °, with respect to the radial direction. Specifically, in the present embodiment, as shown in fig. 3, the first inlet 31 may be provided toward the outside of the body 20 in the radial direction. The first outlet 32 is directed axially outwardly of the body 20, i.e. in a direction away from the body 20 in the axial direction. It should be noted that "toward the axially outer side of the body" may be toward the axially outer side of the body in a direction parallel to the axial direction, or may be at a small angle, for example, 0 ° to 30 ° with respect to the axial direction. Specifically, in the present embodiment, as shown in fig. 3, the first outlet 32 may be provided above the body 20 toward the axially outer side of the body 20 in parallel with the axial direction. Preferably, the first inlet 31 is closer to the body 20 than the first outlet 32 in the axial direction. Specifically, in the present embodiment, the first outlet 32 may be provided above the first inlet 31 in the axial direction.

To create a venturi effect to facilitate the flow of flue gas, the cross-sectional area of the flue gas channel 30 is arranged to be larger at the first inlet 31 than at the first outlet 32. Preferably, the cross-sectional area of the flue gas channel 30 is smallest at the first outlet 32. That is, the cross-sectional area of the flue gas channel 30 may be changed according to actual needs, only that the cross-sectional area of the flue gas channel 30 is required to be minimum at the first outlet 32. As an example, in the present embodiment, the smoke canal 30 gradually decreases from the first inlet 31 to the first outlet 32, so that the air flow is smoother while flowing in the smoke canal 30 and the smoke canal 30 is easily processed and manufactured. However, the shape of the smoke channel 30 is not limited to the present embodiment, and the cross-sectional area of the smoke channel 30 may be gradually reduced and then maintained, or may be changed in a wave shape.

In particular, as shown in fig. 2-4, in the present embodiment, the smoke passageway 30 may be formed by a smoke passageway member 40. The smoke passageway member 40 may include an outer plate 41, an inner plate 42, and an axial baffle 43. The axial baffle 43 is connected to both sides of the outer side plate 41 and the inner side plate 42. Thus, a cavity is formed in the interior of the smoke passage member 40, which constitutes the smoke passage 30. As shown in fig. 2 and 3, the outer and inner plates 41 and 42 are preferably arc-shaped, and the axial baffle 43 is thin plate-shaped, so that the flow of the air flow in the flue gas channel 30 is smoother.

As is clear from fig. 2 and 3, the flue gas channel member 40 has an upper end arranged in the axial direction, which surrounds the first outlet 32 constituting the flue gas channel 30. Specifically, the ends of the outer plate 41, the inner plate 42 and the axial baffle 43 forming the first outlet 32 lie in the same plane, which may be parallel to the radial direction of the body 20. More specifically, the end of the first outlet 32 formed by the outer side plate 41 and the inner side plate 42 is a part of concentric circles. This makes it possible to make the opening size of the first outlet 32 constant in the radial direction of the concentric circles, thereby making the air flow coming out of the first outlet 32 smoother. Preferably, as shown in fig. 4, the radius of the end of the inner side plate 42 forming the first outlet 32 is smaller than the radius of the cavity 22, and the radius of the end of the outer side plate 41 forming the first outlet 42 is close to the radius of the cavity 22.

On the other hand, it is preferable that the smoke passageway member 40 has another lower end portion disposed laterally outwardly, which surrounds the first inlet 31 constituting the smoke passageway 30. Specifically, when viewed from the axial direction, the projections of the end portions of the outer side plate 41 and the inner side plate 42 forming the first inlet 31 in the axial direction completely coincide. More specifically, the end portions of the first inlet 31 formed by the outer and inner side plates 41, 42 have the same radius for ease of machining and fabrication, and in particular for ease of connecting the axial baffle 43 to both sides of the outer and inner side plates 41, 42. Preferably, in the present embodiment, the radius of the end of the inner side plate 42 forming the first inlet 31 is greater than the radius of the cavity 22. As described above, since the radius of the end of the inner side plate 42 forming the first outlet 32 is smaller than the radius of the cavity 22, when the radius of the end of the inner side plate 42 forming the first inlet 31 is larger than the radius of the cavity 22, the smoke passage member 40 may form a generally tapered passage as a whole inclined with respect to the axial direction of the body so that the first outlet 32 may face the lateral direction of the body.

Furthermore, it is preferred that the axial baffle 43 extends into the cavity 22 of the body 20 in an axial direction and extends in a radial direction. In other words, the axial baffle 43 is radially distributed within the cavity 22 when viewed in the axial direction. In particular, the axial baffle 43 may extend in a radial direction to the inner surface of the side wall 21 of the body 20. The axial flow guide plate 43 plays an axial flow guide role on the combustion-supporting gas b in the cavity 22, the flow channels of the combustion-supporting gas b are separated by the axial flow guide plate 43 in the cavity 22, the flow of the combustion-supporting gas b in each flow channel is not interfered, and the flow field is stabilized.

Preferably, the axial baffle 43 has an inclined end at one end. In particular, the inclined end portion is located in the cavity 22 and gradually increases in size in the axial direction in a radially outward direction, i.e., toward the side wall 21 of the body 20 or in a direction close to the side wall 21. Specifically, as shown in fig. 2, the inclined end portion is located at a lower portion of the axial baffle 43 in a radially outward direction, i.e., toward the side wall 21 of the body 20 or in a direction close to the side wall 21, and the length dimension of the axial baffle 43 in the axial direction may be linearly increased. The inclined ends of the axial flow guide plates 43 in the cavity 22 may reduce the partial cross-sectional area of the cavity 22, i.e. form a partial tapering channel for delivering the combustion gas b, which acts as a speed-increasing flow straightening for the combustion gas b and may enhance the stability of the flame flow field during combustion, in particular in the auxiliary fuel injection device 70, which will be mentioned below. Alternatively, in other embodiments, the end of the axial deflector 43 located in the cavity 22 may have no inclined structure, that is, the length dimension of the end of the axial deflector 43 in the axial direction is unchanged in the radially outward direction, that is, toward the side wall 21 of the body 20 or in the direction close to the side wall 21.

As shown in fig. 2-4, a first fuel injection device 50 of the gas burner 10 is disposed in the cavity 22. The first fuel injection device 50 may include a first nozzle 51 and a first fuel gas delivery pipe 52 for supplying fuel gas to the first nozzle 51. Preferably, the first nozzle 51 is disposed in the axial direction and faces the outside of the body 20. In particular, as can be seen clearly in fig. 4, the first nozzle 51 has a spray end which is disposed toward the outside of the body 20 in the axial direction. In the present preferred embodiment, the gas burner 10 is provided with six first fuel injection devices 50 and first nozzles 51, which are disposed at intervals along the circumferential direction of the body 20. However, the number of first fuel injection devices 50 is not limited to the present embodiment, and any other suitable number of first fuel injection devices 50 may be provided as needed. In addition, the angle of the first spraying device or the first nozzle may be fine-tuned as desired, for example, inclined radially inward or outward by 0-5 °, etc.

Preferably, the first fuel injection means 50 extends in an axial direction into the flue gas channel 30. Specifically, in the present embodiment, as shown in fig. 2-4, the first fuel injection device 50 may extend through the inner side plate 42 of the smoke passageway member 40. Preferably, the injection end of the first nozzle 51 is located within the flue gas channel 30. In particular, the injection end of the first nozzle 51 is closer to the body 20 than the first outlet 32 in the axial direction in order to create a strong negative pressure in the flue gas channel 30, which will be described in detail later. Specifically, in the present embodiment, as shown in fig. 3, the injection end of the first nozzle 51 is located below the first outlet 32 in the axial direction. In the present preferred embodiment, two first fuel injection devices 50 are provided within each flue gas channel 30. Specifically, each adjacent two of the first fuel injection devices 50 extend in the axial direction into the same smoke passage 30. However, the number of the first fuel injection devices 50 in each smoke passage 30 is not limited to the present embodiment, and one or more than two first fuel injection devices 50 may be provided in each smoke passage as required.

Furthermore, in order to supply the first fuel injection device 50 with fuel gas, the fuel gas burner 10 may further comprise a fuel gas supply line 25. The gas a is introduced into the gas delivery main pipe 25, and the first gas delivery pipe 52 communicates the gas delivery main pipe 25 with the first nozzle 51, and the first fuel injection device 50 injects high-speed gas through the first nozzle 51. The speed of the high-speed gas may be set according to the design power of the gas burner 10. Preferably, the velocity of the high velocity gas may be 80 to 300m/s. The first nozzle 51 sprays high-speed fuel gas at a high speed, so that the fuel gas can be sprayed far and relatively prolonged when mixed with air, the fuel gas can be combusted in a longer time range, and the generation of NOx, particularly thermal NOx, is reduced. On the other hand, according to the venturi effect, the furnace flue gas in the flue gas channel 30 can be sucked and sprayed out, at this time, a strong negative pressure is formed in the flue gas channel 30, and the pressure in the furnace is greater than the pressure in the flue gas channel, so that the high-temperature furnace flue gas c can enter the flue gas channel 30 under the action of the pressure. On the one hand, the high-temperature hearth flue gas temperature is higher, so that the combustion of the fuel gas at the first nozzle 51 is stabilized, and the combustion is stabilized in a wide load range. On the other hand, the high temperature furnace flue gas c is oxygen-lean, thus enabling a slow combustion at the first fuel injection device 50, reducing the generation of NOx, in particular thermal NOx.

As shown in fig. 4, the lateral fuel injection device 60 of the gas burner 10 may comprise a lateral nozzle 61 and a second gas delivery conduit 62. The second gas delivery pipe 62 communicates the gas delivery header 25 with the lateral nozzle 61 to supply gas to the lateral nozzle 61. The lateral nozzle 61 sprays fuel gas in a lateral direction. Wherein the velocity of the gas ejected laterally from the lateral nozzle 61 is smaller than the velocity of the gas ejected from the first nozzle 51.

In the present preferred embodiment, the gas burner 10 is provided with three lateral fuel injection devices 60, the lateral fuel injection devices 60 being arranged at equal intervals along the circumference of the body 20 and between adjacent two of the flue gas channels 30. The number of the lateral fuel injection devices 60 is not limited to the present embodiment, and any other number of the lateral fuel injection devices 60 may be provided as needed.

Preferably, the lateral nozzles 61 of the lateral fuel injection device 60 are disposed laterally outwardly toward the body 20. Specifically, the lateral nozzle 61 has a spray end, the spray end of the lateral nozzle 61 being disposed laterally outwardly of the body 20. Further preferably, the lateral nozzle 61 may be provided to extend in a radial direction and toward the outside of the body 20. However, the arrangement of the lateral nozzle 61 is not limited to the present embodiment. The lateral nozzles 61 may be angled with respect to the radial direction, as desired. For example, in other embodiments, the lateral nozzles 61 may be disposed at an angle to the radial direction, such as 0 ° to 30 °. The lateral nozzles 61 of the lateral fuel injection device 60 may have a divergent angle. In the present application, the "divergence angle" of the lateral nozzle 61 refers to an angle between a sidewall of the lateral nozzle 61 with respect to a central axis of the lateral nozzle 61. As an example, the divergence angle may be designed to be 0 ° to 60 °, for example 45 °, according to actual needs. Preferably, the lateral nozzle 61 of the lateral fuel injection device 60 is configured such that the jet cone angle of the gas jet injected via the lateral nozzle 61 is 0 ° to 120 °. As an example, the jet cone angle may be designed to be 0 ° to 120 °, for example 90 °, according to actual needs, so that the fuel gas may be injected into a wide space.

Furthermore, the gas burner 10 may also comprise lateral deflectors 23. The lateral flow guide plate 23 may be provided at the lateral nozzle 61 for guiding a portion of the combustion-supporting gas b in the cavity 22 to a lateral direction so that the fuel gas ejected from the lateral nozzle 61 is mixed with the lateral combustion-supporting gas b1 and then burned. On the one hand, a high-temperature flue gas containing a certain amount of nitrogen-containing chemical intermediates can be generated, so that fresh high-temperature flue gas is always present in the flue gas laterally distributed around the gas burner 10. These high temperature fumes can also be entrained into the fume channel 30 with the high temperature furnace fumes due to the venturi effect, facilitating the NOx reduction mechanism, so that low nitrogen combustion of the gas burner 10 can be achieved. On the other hand, the lateral fuel injection device 60 may split part of the fuel gas so that combustion of part of the fuel gas occurs laterally of the end of the gas burner 10, reducing the combustion load of the first fuel injection device 50 of the gas burner 10 and the auxiliary fuel injection device 70 (if provided) to be mentioned later, which is advantageous for reducing the generation of thermal NOx.

Specifically, in the present embodiment, as shown in fig. 3 and 4, the lateral baffle plates 23 are disposed between the adjacent two smoke passage members 40 and mounted on the adjacent two axial baffle plates 43. In this way, it may not be necessary to provide additional mounting components to mount the lateral baffles 23. Preferably, the mounting position of the lateral baffle 23 in the axial direction is adjustable to obtain the desired lateral combustion gas flow rate. For example, a plurality of mounting holes may be provided in the axial direction on the axial baffle 43. When the side deflector 23 is mounted, the side deflector 23 may be selectively mounted to one of the plurality of mounting holes on the axial deflector 43 by a fastener (e.g., a bolt) or the like according to the actual situation (e.g., the kind of combustion gas actually used, etc.). Of course, those skilled in the art will appreciate that the lateral baffle 23 may be otherwise positionally adjustably mounted to the axial baffle 43 in an axial direction. In the present preferred embodiment, the gas burner 10 may be provided with three lateral deflectors 23, however, the number of lateral deflectors 23 is not limited to the present embodiment, and any other number of lateral deflectors 23 may be provided as needed.

Preferably, as shown in fig. 4, the lateral baffle 23 is provided at the lateral nozzle 61, and the lateral nozzle 61 extends through the lateral baffle 23. The lateral baffle 23 may include a first portion 231 and a second portion 232. The first portion 231 extends in a generally axial direction and is disposed within the cavity, and the second portion 232 is coupled to the first portion 231. The second portion 232 may extend at ±30° with respect to the radial direction, i.e. the second portion 232 extends at an angle of 0 ° to 30 ° with respect to the radial direction. Preferably, the second portion 232 extends in a radial direction. The combustion-supporting gas in the cavity 22 passes through the lateral deflectors 23 and flows along the lateral deflectors 23 so as to flow into the lateral extent of the end of the body 20, mixing with the gas supplied by the lateral nozzles 61.

Preferably, the connection between the first portion 231 and the second portion 232 may be a circular arc connection, so as to have a better flow guiding effect on the combustion-supporting gas. Of course, the connection between the first portion 231 and the second portion 232 may be angled. Optionally, the first portion 231 and the second portion 232 are connected at right angles. It is further preferred that the projection of the injection end of the lateral nozzle 61 in the axial direction is located inside the body 20, and the projection of the second portion 232 of the lateral baffle 23 in the axial direction is located at least partly outside the body 20, as seen in the axial direction. That is, the end of the second portion 232 is farther from the central axis of the body 20 in the radial direction than the injection end of the lateral nozzle 61.

In addition, as shown in fig. 2-4, the gas burner 10 may also include an auxiliary fuel injection device 70. The auxiliary fuel injection device 70 is also provided at an end of the body 20, and faces outward in the axial direction. The injection speed of the fuel gas in the auxiliary fuel injection device 70 is smaller than the injection speed of the fuel gas in the first fuel injection device 50. Since the injection speed of the fuel gas in the auxiliary fuel injection device 70 is low, the auxiliary fuel injection device 70 can achieve stable combustion of the fuel gas burner 10. In the present preferred embodiment, the gas burner 10 may be provided with three auxiliary fuel injection devices 70. However, the number of auxiliary fuel injection devices 70 is not limited to the present embodiment, and any suitable number of auxiliary fuel injection devices 70 may be provided as needed.

Specifically, in the present embodiment, as shown in fig. 2 to 4, the auxiliary fuel injection device 70 may include an auxiliary nozzle 71 and a third gas delivery pipe 72 (i.e., the second gas delivery pipe 62). The auxiliary nozzles 71 are disposed to be spaced apart in the circumferential direction of the body 20 and toward the axially outer side of the body 20. In particular, as can be seen clearly in fig. 3, the auxiliary nozzle 71 has a spray end which is arranged in the axial direction. The auxiliary nozzles 71 are arranged between two adjacent axial baffles 43 (outside the flue gas channel 30) and above the lateral nozzles 61 at a distance from the lateral nozzles 61. Preferably, the auxiliary nozzle 71 is arranged coaxially with the first nozzle 51. The auxiliary nozzle 71 may be farther from the body in the axial direction than the first nozzle 51. Specifically, as shown in fig. 4, the axial height of the injection end of the auxiliary nozzle 71 is higher than that of the injection end of the first nozzle 51. Alternatively, the axial height of the injection end of the auxiliary nozzle 71 may be equal to or lower than the axial height of the injection end of the first nozzle 51.

The third gas delivery pipe 72 communicates the auxiliary nozzle 71 with the gas delivery main pipe 25 to supply gas to the auxiliary nozzle 71. Preferably, the fuel gas injection speed of the auxiliary fuel injection device 70 is smaller than the fuel gas injection speed of the first fuel injection device 50. Specifically, the gas injection speed of the auxiliary nozzle 71 is smaller than the gas injection speed of the first nozzle 51.

It should be noted that, the third gas delivery pipe 72 and the second gas delivery pipe 62 may be different pipes for delivering the gas respectively, however, in the preferred embodiment, the third gas delivery pipe 72 and the second gas delivery pipe 62 may be the same pipe for reducing the cost. Therefore, in the following description, only the second gas delivery pipe 62 is used for illustration.

The conduit diameter of the first fuel gas delivery conduit 52 may be smaller than the conduit diameter of the second fuel gas delivery conduit 62 such that the injection rate of fuel gas in the first fuel injection device 50 is higher, while the injection rates of fuel gas in the auxiliary fuel injection device 70 and the side fuel injection device 60 are lower. Alternatively, the conduit diameter of the first gas delivery conduit 52 may be equal to the conduit diameter of the second gas delivery conduit.

In addition, the gas burner 10 may further include a regulating valve 24, and the regulating valve 24 may be provided on one of the first gas delivery pipe 52 and the second gas delivery pipe 62 to regulate the flow rate of the gas in each gas pipe, thereby controlling the injection rate of the gas in each fuel injection device and adjusting the operation state of the gas burner 10. This will be described in detail below.

Preferably, the auxiliary fuel injection device 70 may also include a flame stabilizing cap 74. A flame stabilizing cap 74 may be provided on the auxiliary nozzle 71. The flame holding shroud 74 may provide for a more stable flame of the jet combustion in the auxiliary fuel injection device 70.

Fig. 1 and 2 clearly illustrate the flame flow field and combustion mode of the gas burner 10. The flame flow field and combustion mode of the gas burner 10 will be described in detail below in conjunction with fig. 1 and 2.

As shown in fig. 1 and 2, the first fuel injection device 50 injects high-speed fuel gas, and creates a strong negative pressure in the flue gas channel 30 while entraining a large amount of furnace flue gas in the flue gas channel 30 due to the venturi effect. The negative pressure ejects the high temperature furnace flue gas c into the flue gas channel 30. In addition, the lateral fuel injection device 60 injects lateral fuel gas, and the lateral fuel gas and the lateral combustion-supporting gas b1 guided by the lateral guide plate 23 are mixed and combusted to generate lateral flame 63. Due to the venturi effect, the high temperature flue gas generated by the lateral flame 63 enters the flue gas channel 30 under pressure together with the surrounding high temperature furnace flue gas. Thus, the composition of the high velocity gas flame of the first fuel injection device 50 may mainly include gas, high temperature furnace flue gas, and high temperature flue gas generated by the side flame 63. On the one hand, the high-speed fuel gas, the high-temperature furnace flue gas and the high-temperature flue gas generated by the lateral flame 63 have the characteristics of oxygen deficiency and fuel enrichment, so that the combustion is slower, and NO is reduced _X Is contained in the composition. On the other hand, the high temperature flue gas generated by the side flame 63 contains a certain amount of nitrogen-containing chemicalsIntermediates, which facilitate NO _X Reduced to nitrogen, can effectively reduce NO _X Is contained in the composition. And the lateral fuel injection device 60 can split part of fuel gas, so that the combustion of part of fuel gas occurs at the lateral direction of the end part of the fuel gas burner 10, thereby reducing the combustion load of the first fuel injection device 50 of the fuel gas burner and being beneficial to reducing the generation of thermal NOx. On the other hand, since the high-temperature furnace flue gas sucked into the flue gas passage 30 and the high-temperature flue gas generated by the side flames 63 are high in temperature, it helps to stabilize the combustion of the fuel gas at the first nozzle 51 on fire, stabilizing combustion over a wide load range. Therefore, the combination of the first fuel injection device, the smoke passage, and the lateral fuel injection device can effectively achieve low-nitrogen combustion, and can stably burn in a wide load range.

In addition, the fuel injected from the auxiliary fuel injection device 70 is mixed with the combustion-supporting gas and burned to generate an auxiliary flame 73. Since the speed of the fuel gas injected from the auxiliary nozzle 71 is relatively low and the flame stabilizing cap 74 is mounted on the auxiliary nozzle 71, the auxiliary fuel injection device 70 can realize stable combustion.

In addition, by adjusting the control valve 24, the gas distribution ratio between the first fuel injection device 50, the lateral fuel injection device 60 and the auxiliary fuel injection device 70 can be realized, and the operating state under different loads and different fuels can be adjusted. Specifically, in the present embodiment, the operating state of the gas burner 10 can be adjusted between the low-nitrogen combustion mode and the stable combustion mode. In the low-nitrogen combustion mode, the gas distribution ratio of the first fuel injection device 50 can be increased, the high-speed gas flame is enhanced, the internal circulation mechanism of the smoke is enhanced, and the low-nitrogen combustion mode is enhanced; in the steady combustion mode, the gas distribution ratio of the side fuel injection device 60 and the auxiliary fuel injection device 70 may be adjusted to intensify the side flame 63 and the auxiliary flame 73, thereby intensifing the steady combustion mode. Eventually, stable combustion and low nitrogen emission capability are achieved simultaneously over a wide load range.

According to the gas burner of the invention, by arranging the flue gas channel at one end of the body, the cross section of the flue gas channel at the inlet is provided with the flue gas channelThe area is larger than the cross-sectional area of the outlet, and the burner further comprises a first fuel injection device and a lateral fuel injection device, so that the first fuel injection device can inject high-speed fuel gas and entrain a large amount of hearth smoke in the smoke channel, negative pressure is formed in the smoke channel, the pressure in the hearth is larger than the pressure in the smoke channel, and high-temperature hearth smoke around the gas burner is continuously injected into the smoke channel under the action of the pressure, so that a smoke internal circulation channel is formed. By arranging the lateral fuel injection device, fresh high-temperature flue gas generated by lateral flame is always distributed in the lateral range of the end part of the gas burner, and the flue gas enters a flue gas channel along with the flue gas of the hearth and is fully mixed with fuel gas sprayed out by the first fuel injection device. The high-speed fuel gas, the high-temperature hearth flue gas and the high-temperature flue gas generated by the lateral flame have the characteristics of oxygen deficiency and fuel enrichment, so that the combustion is slow, and the emission of NOx, particularly thermal NOx, can be reduced. In addition, because a certain amount of nitrogen-containing chemical intermediate substances are generated after the combustion of the fuel gas injected by the lateral fuel injection device, NO is facilitated _X Can further reduce NOx emissions. And the lateral fuel injection device can split partial fuel gas, so that the combustion of the partial fuel gas occurs in the lateral direction of the end part of the fuel gas burner, the combustion load of the first fuel injection device of the fuel gas burner is reduced, and the generation of thermal NOx is reduced. In addition, the high-temperature furnace flue gas sucked into the flue gas channel and the high-temperature flue gas generated by lateral flame have higher temperature, so that the ignition of the fuel gas at the first nozzle is stabilized, and the combustion is stabilized in a wide load range. In summary, the gas burner according to the present invention can effectively achieve low-nitrogen combustion and can stably burn in a wide load range.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting of the invention. Terms such as "disposed" or the like as used herein may refer to either one element being directly attached to another element or one element being attached to another element through an intermediate member. Features described herein in one embodiment may be applied to another embodiment alone or in combination with other features unless the features are not applicable or otherwise specified in the other embodiment.

The present invention has been illustrated by the above-described embodiments, but it should be understood that the above-described embodiments are for purposes of illustration and description only and are not intended to limit the invention to the embodiments described. Those skilled in the art will appreciate that many variations and modifications are possible in light of the teachings of the invention, which variations and modifications are within the scope of the invention as claimed.

Claims

1. A gas burner, comprising:

a first fuel injection device disposed in the cavity and extending into the flue gas channel, the first fuel injection device comprising a first nozzle having an injection end located within the flue gas channel;

a lateral fuel injection device for injecting lateral fuel gas, the lateral fuel injection device comprising a lateral nozzle facing the lateral direction of the body, so that the injected lateral fuel gas is mixed with lateral combustion-supporting gas and then combusted to generate lateral flame; and

a lateral deflector arranged at the lateral nozzle for deflecting combustion gases towards the lateral nozzle, the lateral deflector comprising a first portion arranged in the cavity and extending in the axial direction and a second portion connected to the first portion and extending at an angle with respect to the radial direction,

the flue gas channel is formed by a flue gas channel member, and the flue gas channel member comprises an arc-shaped outer side plate, an arc-shaped inner side plate and axial guide plates connected to two sides of the outer side plate and the inner side plate.

2. The gas burner of claim 1, wherein the cross-sectional area of the flue gas channel decreases progressively from the first inlet to the first outlet.

3. The gas burner of claim 1, wherein the first inlet is axially closer to the body than the first outlet.

4. The gas burner of claim 1, wherein the lateral nozzles extend in a radial direction.

5. The gas burner of claim 1, wherein the included angle of the second portion with respect to the radial direction is from 0 ° to 30 °.

6. The gas burner of claim 1, wherein the first fuel injection means passes through the inner plate.

7. The gas burner of claim 1, wherein the ends of the inner and outer plates forming the first outlet lie in the same plane parallel to the radial direction of the body, both forming part of concentric rings.

8. The gas burner of claim 1, wherein the radius of the end of the inner plate forming the first outlet is smaller than the radius of the cavity, and the radius of the end of the inner plate forming the first inlet is greater than the radius of the cavity.

9. The gas burner of claim 1, wherein the radius of the end of the inner side plate forming the first inlet is equal to the radius of the end of the outer side plate forming the first inlet.

10. The gas burner of claim 1, wherein the axial baffle extends into the cavity in an axial direction and extends in a radial direction, the lateral baffle being mounted to the axial baffle.

11. The gas burner of claim 10, wherein the lateral baffle is adjustably mounted to the axial baffle in position along the axial direction.

12. The gas burner of claim 10, wherein said axial baffle extends in a radial direction to an inner surface of said sidewall, said axial baffle having an inclined end within said cavity, said inclined end increasing in size in an axial direction in a radially outward direction.

13. The gas burner of claim 1, wherein the lateral nozzle of the lateral fuel injection device is configured such that the jet cone angle of the injected jet is 0 ° to 120 °.

14. The gas burner of claim 1, wherein the first nozzle is oriented outwardly of the body in an axial direction and an injection end of the first nozzle is closer to the body than the first outlet in the axial direction.

15. The gas burner of claim 1, further comprising an auxiliary fuel injection device facing outward in the axial direction, the injection velocity of the gas in the auxiliary fuel injection device being less than the injection velocity of the gas in the first fuel injection device.

16. The gas burner of claim 15, further comprising a gas delivery manifold;

the first fuel injection device comprises a first fuel gas delivery pipe communicated with the fuel gas delivery main pipe, the lateral fuel injection device comprises a second fuel gas delivery pipe communicated with the fuel gas delivery main pipe, and the second fuel gas delivery pipe communicates the auxiliary fuel injection device with the fuel gas delivery main pipe;

the gas burner further includes a regulator valve disposed on one of the first gas delivery conduit and the second gas delivery conduit.

17. The gas burner of claim 1, including a plurality of said flue gas passages and a plurality of said lateral fuel injection devices, said plurality of flue gas passages being circumferentially spaced along said body, said lateral fuel injection devices being located between adjacent two of said flue gas passages.

18. The gas burner of claim 17, wherein a plurality of said first fuel injection devices are disposed within each of said flue gas passages.

19. The gas burner of claim 1, wherein a cross-sectional area of the flue gas channel is smallest at the first outlet.