A burner

Abstract

The application discloses a burner, which comprises a shell, an ignition device and a plurality of fuel nozzles. The shell is connected with a rear cover and a fire cover, and the shell, the rear cover and the fire cover surround a first chamber. The rear cover is provided with a shunt chamber and connected with a main gas pipe communicating with the shunt chamber. The fire cover is provided with a central nozzle and a combined nozzle. The shell is provided with a first air channel communicating with the first chamber. The ignition device is located at the center of the first chamber. The plurality of fuel nozzles are circumferentially and uniformly distributed around the ignition device, and one end of each fuel nozzle communicates with the shunt chamber, and the other end of each fuel nozzle penetrates through the fire cover and is provided with a nozzle. The nozzles of the fuel nozzles are located outside the combined nozzle. The fuel nozzles are provided with a plurality of first through holes communicating with the first chamber. The burner can disperse the concentrated torch combustion of the traditional burner into multi-point combustion of a plurality of small flames, form a larger flame volume, and then reduce the combustion temperature, so as to reduce the generation of NOx.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of burners, in particular to a burner. BACKGROUND

[0002] It is an urgent environmental protection problem to reduce the nitrogen oxides (NOx) discharged by fuel combustion. At present, there are many low-NOx burners on the market, both foreign brands and domestic self-produced, which are widely used in newly built gas boilers. However, most of the burners use centralized torch combustion, which causes high oxygen concentration in the combustion area, small flame volume, fast combustion reaction, and high combustion temperature, resulting in the generation of a large amount of NOx. SUMMARY

[0003] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application proposes a burner which can disperse the centralized torch combustion of the traditional burner into multi-point combustion of multiple small flames, form a larger flame volume, and thus reduce the combustion temperature, thereby reducing the generation of NOx.

[0004] According to the burner proposed in the present application, the burner comprises a shell, a rear cover and a fire cover connected to the shell, the rear cover and the fire cover are arranged opposite to each other, the shell, the rear cover and the fire cover surround a first chamber, the rear cover is provided with a shunt chamber, the rear cover is connected with a main gas pipe communicating with the shunt chamber, the fire cover is provided with a center nozzle and a combined nozzle, and the shell is provided with a first air passage communicating with the first chamber; an ignition device is located at the center of the first chamber, the ignition device is connected to the fire cover and communicates with the center nozzle; a plurality of fuel nozzles are circumferentially and uniformly distributed around the ignition device and one end of each fuel nozzle communicates with the shunt chamber, the other end of each fuel nozzle penetrates through the fire cover and is provided with a nozzle, the nozzles of the plurality of fuel nozzles are located outside the combined nozzle, each fuel nozzle is provided with a plurality of first through holes communicating with the first chamber, and the center nozzle, the combined nozzle and the nozzles of the fuel nozzles are sequentially arranged from the center to the outer ring of the fire cover.

[0005] According to the burner of the above-mentioned embodiments of the present application, at least the following beneficial effects are achieved:

[0006] The plurality of fuel nozzles disperse the centralized torch combustion of the traditional burner into multi-point combustion of multiple small flames, increase the combustion area of the flame, form a larger flame volume, and thus reduce the combustion temperature, thereby reducing the generation of NOx. The combined nozzle can supplement oxygen to the flame of the burner, and at the same time, the high-speed jet flow of the burner causes the backflow of the flue gas in the combustion area, which can reduce the oxygen concentration in the combustion area, expand the combustion area, and thus reduce the combustion temperature, thereby reducing the generation of NOx.

[0007] According to some embodiments of the present application, the combined nozzle comprises a first nozzle, a second nozzle, a third nozzle and a fourth nozzle, which are in communication with the first chamber, and are arranged in sequence from the center of the fire cover to the outer ring.

[0008] According to some embodiments of the present application, the first nozzle and the second nozzle are both spiral, the third nozzle is a plurality of circular nozzles arranged in a circumferential direction, and the third nozzle is inclined towards the center nozzle, and the fourth nozzle is a plurality of strip-shaped nozzles arranged in a circumferential direction.

[0009] According to some embodiments of the present application, the fuel nozzle comprises a first nozzle and a second nozzle, and the length of the nozzle of the first nozzle from the fire cover is greater than the length of the nozzle of the second nozzle from the fire cover.

[0010] According to some embodiments of the present application, the first nozzle is four and is arranged in a circumferential direction around the ignition device, and the second nozzle is eight, and two second nozzles are arranged between two adjacent first nozzles.

[0011] According to some embodiments of the present application, the nozzle of the fuel nozzle is inclined towards the center nozzle, the nozzle of the fuel nozzle is provided with a plurality of first nozzles, and the outer wall of the nozzle of the fuel nozzle is provided with a plurality of second nozzles in a circumferential direction.

[0012] According to some embodiments of the present application, the ignition device is a fuel injection gun, the fuel injection gun comprises a second chamber, the second chamber is provided with an ignition gas pipe, the fuel injection gun is provided with an air inlet pipe in communication with the ignition gas pipe, the nozzle of the ignition gas pipe is in communication with the center nozzle, the second chamber is provided with an igniter, and the ignition electrode of the igniter is arranged at the nozzle of the ignition gas pipe.

[0013] According to some embodiments of the present application, the fuel injection gun is installed on the rear cover, the fuel injection gun extends through the first chamber, and the air inlet end of the fuel injection gun is located outside the shell.

[0014] According to some embodiments of the present application, the air inlet end of the fuel injection gun is provided with a second air passage in communication with the second chamber, the nozzle end of the fuel injection gun is provided with a third nozzle, and the outer peripheral wall of the ignition gas pipe is uniformly provided with a plurality of second through holes in communication with the second chamber.

[0015] According to some embodiments of the present application, the first air passage is connected to an air pipeline and a return air pipeline at the same time, the air pipeline is used for inputting external air, and the return air pipeline is used for connecting a waste gas treatment device of a boiler.

[0016] Additional aspects and advantages of the present application will be in part apparent and in part pointed out below in the description of embodiments of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0017] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description of embodiments of the present application, taken in conjunction with the accompanying drawings.

[0018] Figure 1 is a structural schematic diagram of a low-nitrogen burner according to some embodiments of the present application;

[0019] Figure 2 is a structural schematic diagram of a fire cap according to some embodiments of the present application;

[0020] Figure 3 is another structural schematic diagram of a fire cap according to some embodiments of the present application;

[0021] Figure 4 is a partial structural schematic diagram of a fuel lance according to some embodiments of the present application;

[0022] Figure 5 is another partial structural schematic diagram of a fuel lance according to some embodiments of the present application;

[0023] Figure 6 is a partial structural schematic diagram of a fuel lance according to some embodiments of the present application.

[0024] In the drawings:

[0025] housing 100; first chamber 110; first air passage 120;

[0026] rear cover 200; main gas pipe 210; shunt chamber 220;

[0027] fire cap 300; central jet 310; first jet 320; second jet 330; third jet 340; fourth jet 350; flame detection hole 360;

[0028] fuel lance 400; first lance 410; second lance 420; first through hole 430; first jet hole 440; second jet hole 450;

[0029] fuel lance 500; second chamber 510; igniting gas pipe 520; second through hole 521; air inlet pipe 530; igniter 540; second air passage 550; third jet hole 560; fourth jet hole 570; fifth jet hole 580; flame detector 590. DETAILED DESCRIPTION

[0030] Embodiments of the present application are described below in detail with reference to the accompanying drawings, wherein the same or similar components or components having the same or similar functions are denoted by the same or similar reference numerals throughout the drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only for the purpose of explaining the present application, and should not be construed as limiting the present application.

[0031] In the description of the present application, it should be understood that the orientation description, such as the orientation or position relationship indicated by up, down, front, back, left, right, etc., is based on the orientation or position relationship shown in the drawings, and is only for the purpose of facilitating the description of the present application and simplifying the description, and does not indicate or imply that the device or component referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present application.

[0032] In the description of the present application, the meaning of several is one or more, the meaning of multiple is more than two, greater than, less than, more than, etc. are understood as not including the number, above, below, etc. are understood as including the number. If it is described as first, second, it is only for the purpose of distinguishing technical features, and should not be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the order of indicated technical features.

[0033] In the description of the present application, unless otherwise explicitly limited, the words such as setting, installing, connecting, etc. should be broadly understood, and those skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0034] In response to the concept of green environmental protection, the traditional coal-fired boiler on the market is constantly being transformed into a gas-fired boiler. However, in most gas-fired boilers after transformation, the burner adopts a centralized torch type combustion mode, which causes problems such as high oxygen concentration in the combustion area, small flame volume, too fast combustion reaction, and high combustion temperature, thereby causing a large amount of NOx to be generated. In view of the above problems, the present application proposes a burner which retains the pressure-bearing structure on the basis of the original coal-fired boiler, replaces the original burner with the burner proposed by the present application to transform into a gas-fired boiler, and can disperse the centralized torch type combustion of the traditional burner into multi-point combustion of multiple small flames, form a larger flame volume, and thus reduce the combustion temperature, thereby reducing the generation of NOx.

[0035] Reference Figure 1According to the application, a burner comprises a shell 100, an ignition device and a plurality of fuel nozzles 400, the shell 100 is connected with oppositely arranged rear cover 200 and fire cover 300, and the shell 100, the rear cover 200 and the fire cover 300 surround a first chamber 110. The rear cover 200 is provided with a separate shunt chamber 220 from the first chamber 110, and the rear cover 200 is further connected with a main gas pipe 210 communicating with the shunt chamber 220, which can deliver the main gas into the shunt chamber 220. The fire cover 300 is provided with a central nozzle 310 and a combined nozzle, the ignition device located at the center of the first chamber 110 is connected with the fire cover 300 and communicates with the central nozzle 310, so that the ignition device can ignite the ignition gas at the central nozzle 310 to form an ignition source, and the shell 100 is provided with a first air passage 120 communicating with the first chamber 110, which can deliver the combustion air into the first chamber 110 through the first air passage 120, and then diffuse to the combustion area of the burner through the combined nozzle to supplement oxygen to the flame, at the same time, the high-speed jet of the burner can be used through the combined nozzle to cause the backflow of the flue gas in the combustion area, which can reduce the oxygen concentration in the combustion area, expand the combustion area, and further reduce the combustion temperature, thereby reducing the generation of NOx. In the embodiment of the application, the connecting member can be a clip or a plate member with other shapes, and the connecting mode can be buckle, screw connection or welding, etc., which will not be described here.

[0036] With reference to Figure 1 According to some embodiments of the application, the plurality of fuel nozzles 400 are circumferentially distributed around the ignition device and one end communicates with the shunt chamber 220, and the other end of the fuel nozzle 400 passes through the fire cover 300 and is provided with a nozzle, and the nozzle of the fuel nozzle 400 is located outside the combined nozzle, so that the main gas in the shunt chamber 220 can be high-speed injected to the outside and ignited by the ignition source of the central nozzle 310. Figure 5 The fuel nozzle 400 is provided with a plurality of first through holes 430 communicating with the first chamber 110, and it can be understood that when the first chamber 110 is filled with combustion air, the high-speed airflow generated by the high-speed injection of the main gas in the fuel nozzle 400 can drive the combustion air in the first chamber 110 into the fuel nozzle 400 through the first through hole 430, and mix with the main gas to provide oxygen for the combustion of the main gas.

[0037] With reference to Figures 1 to 3According to some embodiments of the present application, the central nozzle 310, the combined nozzle and the nozzles of the fuel injection pipes 400 are arranged from the center to the outer circle of the fire cap 300, the ignition device ignites the ignition gas and forms an ignition source at the central nozzle 310, when the ignition source is stable, the multiple fuel injection pipes 400 inject the main gas and are ignited by the ignition source, the concentrated torch combustion of the traditional burner is dispersed into multiple small flame multi-point combustion, the combustion area of the flame is increased, a larger flame volume is formed, and the combustion temperature is reduced, thereby reducing the generation of NOx. At the same time, the combined nozzle continuously sprays combustion air to supplement oxygen for subsequent flame combustion, and the high-speed jet of the burner causes the flue gas in the combustion area to flow back, which can reduce the oxygen concentration in the combustion area, expand the combustion area, and thus reduce the combustion temperature, thereby reducing the generation of NOx.

[0038] Referring to Figures 1 to 3 According to some embodiments of the present application, the combined nozzle includes a first nozzle 320, a second nozzle 330, a third nozzle 340 and a fourth nozzle 350 which are in communication with the first chamber 110, and the first nozzle 320, the second nozzle 330, the third nozzle 340 and the fourth nozzle 350 are arranged from the center to the outer circle of the fire cap 300. The first nozzle 320 and the second nozzle 330 are both in a spiral shape, which can expand the area of the combustion air injection, the third nozzle 340 is a plurality of circular nozzles which are arranged in a circumferential direction and are inclined towards the direction of the central nozzle 310, and the fourth nozzle 350 is a plurality of strip-shaped nozzles which are arranged in a circumferential direction. It can be understood that when the burner is used in a boiler, the combined nozzle composed of multiple nozzles of different forms can use the high-speed jet of the burner to form jets of different angles at the outer side of the fire cap 300 to suck the flue gas in the boiler, so that the flue gas circulates and diffuses in the boiler, which can reduce the oxygen concentration in the combustion area, thereby reducing the combustion temperature and reducing the generation of NOx.

[0039] Referring to Figure 3 According to some embodiments of the present application, the fuel injection pipe 400 includes a first injection pipe 410 and a second injection pipe 420, the length of the nozzle of the first injection pipe 410 from the fire cap 300 is greater than the length of the nozzle of the second injection pipe 420 from the fire cap 300, that is, the first injection pipe 410 is a long injection pipe and the second injection pipe 420 is a short injection pipe. In some embodiments, the first injection pipe 410 is four and is arranged in a circumferential direction around the ignition device, and the second injection pipe 420 is eight, two second injection pipes 420 are arranged uniformly between adjacent two first injection pipes 410, the ignition device ignites the ignition gas as primary combustion, after the ignition source is stable, the eight second injection pipes 420 are ignited as secondary combustion, and finally the four first injection pipes 410 are ignited as tertiary combustion, so that the burner disperses the concentrated torch combustion of the traditional burner into multiple small flame multi-point combustion through the structure of grading fuel and grading air, thereby forming a larger flame volume, reducing the combustion temperature and reducing the generation of NOx.

[0040] Referring to Figure 1 and Figure 4 , according to some embodiments of the present application, the direction of the nozzle of the fuel injection pipe 400 is inclined towards the central nozzle 310, so that the high-speed jet of the burner can cause the smoke backflow of the combustion area, the oxygen concentration of the combustion area can be reduced, the combustion area can be expanded, and the combustion temperature can be reduced, thereby reducing the generation of NOx. The nozzle of the fuel injection pipe 400 is provided with a plurality of first injection holes 440, and the outer wall of the fuel injection pipe 400 near the nozzle is circumferentially provided with a plurality of second injection holes 450. By injecting fuel through the plurality of holes, the flame volume can be further expanded, and the combustion temperature can be further reduced, thereby reducing the generation of NOx.

[0041] Referring to Figure 1 and Figure 6 , according to some embodiments of the present application, the ignition device is a fuel injection gun 500, which is installed on the rear cover 200, extends through the first chamber 110, and has an air inlet end outside the shell 100. The fuel injection gun 500 comprises a second chamber 510 provided with an ignition gas pipe 520, and an air inlet pipe 530 communicating with the ignition gas pipe 520, so that the ignition gas can enter the ignition gas pipe 520 through the air inlet pipe 530. The nozzle of the ignition gas pipe 520 communicates with the central nozzle 310, and the second chamber 510 is provided with an igniter 540, and the ignition electrode of the igniter 540 is arranged at the nozzle of the ignition gas pipe 520, so that the ignition gas jetted out of the ignition gas pipe 520 can be ignited by the ignition electrode to form an ignition source. In the embodiments of the present application, the connecting member can be a clip or a plate member of other shapes, and the connection mode can be buckling, screwing, welding or the like, which will not be described here.

[0042] Referring to Figure 1 and Figure 6 , according to some embodiments of the present application, the air inlet end of the fuel injection gun 500 is provided with a second air passage 550 communicating with the second chamber 510, the nozzle end of the fuel injection gun 500 is provided with a third injection hole 560, and the outer peripheral wall of the ignition gas pipe 520 is uniformly provided with a plurality of second through holes 521 communicating with the second chamber 510. It can be understood that the ignition air enters the second chamber 510 through the second air passage 550, and the high-speed airflow generated by the high-speed jet of the ignition gas in the ignition gas pipe 520 can bring the ignition air into the ignition gas pipe 520 through the second through holes 521, so that the ignition gas and the ignition air are mixed, and oxygen is provided for the combustion of the ignition gas. The remaining ignition air can be diffused to the central nozzle 310 through the third injection hole 560. Referring to Figure 6In some embodiments, the third injection hole 560 is inclined towards the direction of the nozzle end of the ignition gas pipe 520, so as to facilitate the ignition air to supplement the subsequent oxygen for the ignition source, and the ignition gas can be stopped after the ignition source is stably combusted, while the ignition air is kept supplied, so that the ignition air can be part of the combustion air, and the influence of the high-temperature combustion air on the fuel injection lance 500 can be effectively blocked.

[0043] Further, with reference to Figure 6 According to some embodiments of the present application, the nozzle end of the ignition gas pipe 520 is provided with a plurality of fourth injection holes 570 and fifth injection holes 580, the fourth injection holes 570 extend along the axial direction of the ignition gas pipe 520, and the fifth injection holes 580 are perpendicular to the fourth injection holes 570. It can be understood that by arranging the fourth injection holes 570 and the fifth injection holes 580 in multiple directions perpendicular to each other, the diffusion area of the ignition gas can be increased, so that the ignition gas can be more easily mixed with the ignition combustion air, so that the ignition gas can be fully and stably combusted while the combustion area of the ignition gas is expanded.

[0044] With reference to Figure 1 and Figure 6 According to some embodiments of the present application, the fuel injection lance 500 is provided with a flame detector 590, which is integrated with the ignition gas pipe 520 in the form of a concentric sleeve, and the flame detector 590 is used to detect the combustion condition in real time according to the combustion characteristics of the flame, so as to ensure the normal operation of the combustor. With reference to Figure 2 In some embodiments, the fire cover 300 is further provided with two symmetrically arranged flame detection holes 360, and the combustor is provided with a flame detector 590 (not shown in the figure) aligned with the flame detection holes 360, and the combustor is further provided with a combustor control circuit, which includes a flameout control circuit connected with a gas electric control valve for controlling the supply of ignition gas, and the above-mentioned flame detector 590 is connected with the combustor control circuit through wires, when the combustion flame formed outside the flame detection hole 360 is extinguished due to poor supply of ignition gas or occlusion of the flow path of the ignition gas pipe, etc., the flame detector 590 will transmit the flameout signal to the flameout control circuit, and then the flameout control circuit will control the gas electric control valve to be closed to cut off the supply of ignition gas.

[0045] With reference to Figure 1According to some embodiments of the present application, the first air passage 120 is provided with two air inlets, one of which is connected with an air pipeline and can input combustion-supporting air, and the other of which is connected with a return air pipeline, which is used to connect with a waste gas treatment device of the boiler and can extract and transport part of the boiler flue gas into the first air passage 120, so that the boiler flue gas is mixed with the combustion-supporting air to form mixed combustion-supporting gas with low oxygen concentration, and then is input into the first chamber 110 for combustion support. By using the mixed combustion-supporting gas with low oxygen concentration to reduce the oxygen concentration of the combustion area of the burner, the combustion reaction speed is reduced, the combustion temperature is reduced, and the generation of NOx is reduced.

[0046] The above describes the embodiments of the present application in detail in combination with the drawings, but the present application is not limited to the above-described embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the present application.

Claims

1. A burner, characterized in that, include: The housing is connected to a rear cover and a flame cap, the rear cover and the flame cap are arranged opposite to each other, the housing, the rear cover and the flame cap surround a first chamber, the rear cover is provided with a diversion chamber, the rear cover is connected to a main gas pipe communicating with the diversion chamber, the flame cap is provided with a central nozzle and a combined nozzle, and the housing is provided with a first air passage communicating with the first chamber. An ignition device is located at the center of the first chamber, the ignition device is connected to the flame cap, and is connected to the central nozzle; Multiple fuel nozzles are evenly distributed around the ignition device and one end of each nozzle is connected to the flow divider chamber. The other end of each fuel nozzle passes through the burner cap and is provided with a nozzle. The nozzles of the multiple fuel nozzles are located outside the combined nozzle. Each fuel nozzle is provided with multiple first through holes connecting to the first chamber. The central nozzle, the combined nozzle, and the nozzles of the fuel nozzles are arranged sequentially from the center of the burner cap to the outer ring. The combined nozzle includes a first nozzle, a second nozzle, a third nozzle, and a fourth nozzle that connect to the first chamber. The first nozzle, the second nozzle, the third nozzle, and the fourth nozzle are arranged sequentially from the center of the burner cap to the outer ring. The first nozzle and the second nozzle are both swirling. The third nozzle is a plurality of circumferentially evenly distributed circular nozzles that are inclined toward the central nozzle. The fourth nozzle is a plurality of circumferentially evenly distributed strip nozzles.

2. The burner according to claim 1, characterized in that, The fuel nozzle includes a first nozzle and a second nozzle, wherein the distance from the nozzle of the first nozzle to the flame cap is greater than the distance from the nozzle of the second nozzle to the flame cap.

3. The burner according to claim 2, characterized in that, There are four first nozzles, which are evenly distributed around the ignition device. There are eight second nozzles, with two second nozzles evenly arranged between two adjacent first nozzles.

4. The burner according to claim 3, characterized in that, The nozzle of the fuel injector is inclined toward the central nozzle, and the nozzle of the fuel injector is provided with a plurality of first nozzle holes, and the outer wall of the fuel injector near the nozzle is provided with a plurality of second nozzle holes in a circumferential manner.

5. The burner according to claim 1, characterized in that, The ignition device is a fuel spray gun, which includes a second chamber. The second chamber is provided with an ignition gas pipe. The fuel spray gun is provided with an air inlet pipe that connects to the ignition gas pipe. The nozzle of the ignition gas pipe is connected to the central nozzle. The second chamber is provided with an igniter, and the ignition electrode of the igniter is located at the nozzle of the ignition gas pipe.

6. The burner according to claim 5, characterized in that, The fuel injector is mounted on the rear cover, extends through the first chamber, and has its air inlet located outside the housing.

7. The burner according to claim 6, characterized in that, The fuel injector has a second air passage at its inlet end that connects to the second chamber, a third nozzle at its nozzle end, and a plurality of second through holes that connect to the second chamber are evenly distributed on the outer peripheral wall of the ignition gas pipe.

8. The burner according to any one of claims 1 to 7, characterized in that, The first air passage connects both an air pipeline and a return air pipeline. The air pipeline is used to input outside air, and the return air pipeline is used to connect to the boiler's exhaust gas treatment equipment.

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