CN221172243U

CN221172243U - Burner with a burner body

Info

Publication number: CN221172243U
Application number: CN202322643233.0U
Authority: CN
Inventors: 杨晓远; 常亮; 李永锋; 陶瑜; 王豪杰; 张奎山
Original assignee: Honeywell Youopai Engineering Technology R&d Co ltd
Current assignee: Honeywell Youopai Engineering Technology R&d Co ltd
Priority date: 2023-09-27
Filing date: 2023-09-27
Publication date: 2024-06-18
Anticipated expiration: 2033-09-27

Abstract

The present utility model provides a burner comprising: a refractory brick in which a first gas passage is opened; a bellows disposed below the refractory brick and having a second gas passage provided therein for communication with the first gas passage; a first gas lance, a gas outlet of which is arranged inside the first gas passage and to which a first combustion air passage for supplying combustion air is assigned for burning gas inside the first gas passage; a second gas lance having a gas outlet arranged outside the refractory brick and being provided with a second combustion air passage for supplying combustion air for burning the gas outside the refractory brick; a negative pressure flue gas return device having a flue gas inlet to the outside of the burner and a flue gas outlet to the second combustion air passage for introducing flue gas generated by combustion into the second combustion air passage by negative pressure. The burner has reduced structural complexity and lower NO _X emissions.

Description

Burner with a burner body

Technical Field

The present utility model relates to a burner, and in particular, to a burner having an internal flue gas recirculation function.

Background

For the burner of the industrial furnace, the emission of NO _X nitrogen oxides is always one of the important indexes. In order to achieve the goal of low NO _X emissions, measures to reduce the oxygen content involved in the combustion process or to reduce the combustion temperature may be taken. For example, common measures for reducing NO _X emissions mainly include gas staging, combustion air staging, flue gas recirculation, steam injection, etc. For flue gas recirculation, the oxygen content participating in the combustion process is reduced through the return of the flue gas, so that the emission of NO _X can be controlled, and the method is realized by adding a plurality of high-temperature fans and related pipelines.

However, the specific addition of external devices for the purpose of recycling the flue gases is necessary, which is likely to affect the spatial layout of the industrial kiln or auxiliary facilities and thus increase the structural complexity of the industrial products.

Disclosure of utility model

According to a different aspect, it is an object of the present utility model to provide an improved burner, wherein the burner has a relatively simplified structure while achieving low NO _X emissions.

In addition, the utility model aims to solve or alleviate other technical problems in the prior art.

The present utility model solves the above-described problems by providing a burner, specifically, comprising:

a refractory brick in which a first gas passage is opened;

a bellows disposed below the refractory brick and having a second gas passage provided therein for communication with the first gas passage;

a first gas lance, a gas outlet of which is arranged inside the first gas passage and to which a first combustion air passage for supplying combustion air is assigned for burning gas inside the first gas passage;

A second gas lance having a gas outlet arranged outside the refractory brick and being provided with a second combustion air passage for supplying combustion air for burning gas outside the refractory brick;

A negative pressure flue gas return device having a flue gas inlet to the outside of the burner and a flue gas outlet to the second combustion air passage for introducing flue gas generated by combustion into the second combustion air passage by negative pressure.

Optionally, in the burner according to the utility model, the negative pressure flue gas return device comprises an ejector pipe and an ejector gun for ejecting ejector gas into the ejector pipe, the ejector pipe is communicated to the outside of the burner by one end and is communicated to the second combustion air channel by the other end, wherein the ejector pipe is of a venturi structure.

Optionally, in the burner according to the utility model, the injection gas is compressed combustion air, compressed nitrogen, or compressed inert gas.

Optionally, in the burner according to the utility model, the first and second combustion air channels are in communication with the same combustion air source.

Optionally, in the burner according to the utility model, the second combustion air channel comprises a central air duct passing through the first gas channel in axial direction to deliver combustion air into the outer space above the refractory bricks, wherein the ejector pipe opens into the central air duct to suck flue gas into the central air duct.

Optionally, in the burner according to the utility model, the combustion air outlet of the central duct is flush with the top of the first gas channel.

Optionally, in the burner according to the utility model, the central wind duct also passes through the second gas channel in the axial direction, wherein a first gap space is present between the outer wall of the central wind duct and the wall of the first gas channel, in which first gap space the gas outlet of the first gas lance is arranged, and a second gap space is present between the outer wall of the central wind duct and the wall of the second gas channel, to which the first combustion air channel opens.

Optionally, in the burner according to the present utility model, the burner further includes a mounting plate, the refractory bricks are fixed at the mounting plate, and the injection pipe is arranged between the refractory bricks and the mounting plate.

Optionally, in the burner according to the present utility model, the burner further comprises a sleeve fixed at the mounting plate, the sleeve surrounding a lower portion of the refractory brick and having a plurality of through holes opened in a peripheral wall thereof, through which the flue gas is guided into the ejector tube.

Optionally, in the burner according to the utility model, a damper structure is provided at the combustion air inlet of the first combustion air channel or at the combustion air inlet of the second combustion air channel for adjusting the amount of the combustion air flowing in.

Such a burner may thereby reduce the structural complexity of the relevant mechanisms for internal recirculation of flue gases and may thereby enable lower NO _X emissions.

Drawings

The above and other features of the present utility model will become apparent with reference to the accompanying drawings, in which,

Fig. 1 shows a schematic perspective view of a burner according to an embodiment of the utility model;

Fig. 2 shows a cross-sectional view of the burner according to fig. 1, however with the sleeve removed.

Detailed Description

It is to be understood that, according to the technical solution of the present utility model, those skilled in the art may propose various alternative structural modes and implementation modes without changing the true spirit of the present utility model. Accordingly, the following detailed description and drawings are merely illustrative of the utility model and are not intended to be exhaustive or to limit the utility model to the precise form disclosed.

Terms of orientation such as up, down, left, right, front, rear, front, back, top, bottom, etc. mentioned or possible to be mentioned in the present specification are defined with respect to the configurations shown in the drawings, which are relative concepts, and thus may be changed according to different positions and different use states thereof. These and other directional terms should not be construed as limiting terms. Furthermore, the terms "first," "second," "third," and the like are used for descriptive and distinguishing purposes only and are not to be construed as indicating or implying a relative importance of the corresponding components.

An embodiment of the burner according to the utility model is explained in more detail below with reference to the perspective view in fig. 1 and the sectional view in fig. 2. The burner includes a refractory brick 110, a windbox 120, a first gas lance 130, a second gas lance 140, and a negative pressure flue gas recirculation device 150 disposed below the refractory brick. Here, the center line of the refractory brick 110 or a straight line parallel to the center may be regarded as the axis direction mentioned herein, in particular, as shown in fig. 2, the vertical direction may be regarded as the axis direction mentioned herein. In addition, the top, bottom, base, etc. presented herein also refer to this axis direction.

A first gas channel 111 is provided in the interior of the refractory brick 110, further optionally the refractory brick 110 is hollow and provided with a cylindrical first gas channel 111 in its centre, in which first gas channel there may be or may flow gas, co-gas, flue gas or any mixture of the three. It should be noted here that the first gas channel is not closed, it communicates with the outside of the burner, through which flue gas generated by the combustion process in the first gas channel can flow to the outside of the burner. The bellows 120 is located below the refractory bricks 110 and has a second gas passage 121 provided therein in communication with the first gas passage 111, and further alternatively, the bellows 120 is configured as a hollow cylinder and has a cylindrical second gas passage 121 provided at the center thereof.

The gas outlet of the first gas lance 130 is arranged inside the first gas channel 111 of the refractory brick 110 and is assigned a first combustion air channel 170 for supplying combustion air thereto, while the gas outlet of the second gas lance 140 is arranged outside the refractory brick 110 and is assigned a second combustion air channel 180 for supplying combustion air thereto, wherein both gas lances communicate with a gas source (not shown) via a gas channel 160. In addition, a regulating valve is provided in the passage of the gas passage 160 near the gas source for regulating the amount of the gas flowing in. In this way, staged combustion can be achieved during operation of the burner, that is to say a first combustion process within the first gas channel 111 (hereinafter, the concept of "inner combustion space" is employed for the first combustion process) and a second combustion process outside the refractory brick 110 (correspondingly, the concept of "outer combustion space" is employed for the second combustion process, hereinafter, wherein the outer combustion space is understood to be outside the burner).

In an alternative embodiment, the first gas lance 130 is fixed to the inner wall of the first gas passage 111 and the pilot burner 112 is also arranged on the inner wall of the first gas passage 111, and the second gas lance 140 is fixed to the outer wall of the refractory brick 110. Specifically, the refractory brick 110, as shown in the drawings, includes two parts, an upper part configured as a cone or a truncated cone gradually shrinking in a direction toward the top, and a lower part configured as a cylinder, wherein a boss extending in an axial direction and having the second gas injection lance 140 embedded therein is provided on an outer periphery of the lower part of the refractory brick. In the assembled state, the second gas spray gun 140 protrudes from above with its gas outlet so as to spray gas to the outside of the burner. Here, the refractory block 110 may be an integral piece or assembled from upper and lower portions.

It should be understood here that the number of the first gas injection lances 130 and the second gas injection lances 140 can be selected as required and can be spatially uniformly arranged in the case of a plurality of them.

In order to achieve a low NO _X emission, the burner 100 is according to the utility model provided with a negative pressure flue gas recirculation device 150, which is arranged below the refractory bricks 110, the flue gas inlet of which opens out to the outside of the burner 100 and the flue gas outlet of which opens out to a second combustion air channel 180 of a second gas lance 140 for the outside. During operation of the burner 100, the oxygen content in the external combustion space is reduced by flue gas recirculation, whereby NO _X emissions can be reduced and overall structural complexity can be reduced in lieu of a high temperature fan. This manner of flue gas recirculation may also be referred to herein as flue gas internal recirculation (IFGR, internal flue gas recirculation).

An alternative embodiment of the negative pressure flue gas recirculation device is given here. As shown in the drawings, the negative pressure flue gas return device 150 includes an ejector pipe 151 and an ejector gun 152, wherein one end of the ejector pipe 151 (which serves as the flue gas inlet) is opened to the external combustion space of the burner and the other end (which serves as the flue gas outlet) is opened to the second combustion air passage 180; the injection lance 152 is used to inject injection gas into the injection pipe 151. According to the utility model, the ejector 151 is a venturi tube, into which the ejector gas is injected to automatically introduce the flue gases back into the second combustion air channel via the ejector tube, in order to reduce the oxygen content involved in the second combustion process and thus the nitrogen oxide emissions. In other words, the negative pressure generated by the injection of the injection gas is used as a power source for the internal recirculation of the fumes. The injection gas can be compressed gas for better flue gas return, for example, compressed combustion air, compressed nitrogen, compressed inert gas or other types of gas which are free of oxygen or low in oxygen, optionally selected.

An alternative embodiment is provided in which the injection gas is combustion air. Specifically, the ejector lance 152 injects combustion air (e.g., compressed air) into the ejector tube 151, at which time flue gas outside the burner 100 is automatically drawn into the ejector tube 151 by means of the negative pressure generated at the ejector tube 151 and thereby the oxygen content ratio in the second combustion air passage 180 is reduced. The venturi-type ejector tube further reduces the structural complexity of the burner. In this case, the amount of the combustion-supporting gas injected into the injection pipe 151 is small and the amount of the combustion-supporting air can be adjusted together with the total amount of the combustion-supporting air flowing through the first and second combustion-supporting air passages 170 and 180 so that a preset ratio of the gas to the combustion-supporting air can be achieved.

In an alternative embodiment, the injection lance 152 may be in communication with the same source of combustion air as the first and second combustion air passages 170, 180. In this case, the injection lance 152 may inject the combustion air having the same pressure as the combustion air in the first combustion air passage 170 or the second combustion air passage 180 into the injection pipe 151. Or further alternatively, the injection lance 152 injects the supercharged combustion air (that is, the gas pressure thereof is higher than the gas pressure of the combustion air in the first combustion air passage 170 or the second combustion air passage 180) into the injection pipe 151 through the supercharger. Or the injection lance 152 may be associated with a dedicated compressed combustion air source, such as a compressed air source.

In an alternative embodiment, the second combustion air passage 180 includes a central air duct 181 extending in an axial direction and passing through the first gas passage 111 and the second gas passage 121 to deliver combustion air into the external combustion space at the top of the refractory bricks 110. The central air duct 181 may be configured as a hollow cylinder, and its outer wall is spaced apart from the wall of the first gas passage 111 and the wall of the second gas passage 121, respectively. Specifically, for example, a first clearance space exists between the outer wall of the center duct 181 and the wall portion of the first gas passage 111, in which the gas outlet of the first gas lance 130 is arranged. On the other hand, a second clearance space exists between the outer wall of the center duct 181 and the wall portion of the second gas passage 121, to which the first combustion air passage 170 opens. In this way, an internal combustion space is realized for the first gas lance 130, which is a hollow cylinder, that is to say, which is enclosed by the outer wall of the central air duct 181 and the wall of the first gas channel 111. Compared with the design scheme that all combustion-supporting air passes through the first gas channel, the internal combustion space of the hollow cylinder can realize oxygen-deficient combustion of fuel gas more accurately, so that the emission of nitrogen oxides in the first fuel gas process is further reduced; in addition, such an internal combustion space is advantageous in that smoke gas formed after combustion of the gas therein is entrained into the external combustion space, thereby affecting nitrogen oxides generated upon combustion of the external gas.

In particular, the combustion air outlet above the central air duct 181 may be flush with the top of the first gas channel 111, that is, the central air duct 181 and the first gas channel 111 are aligned above in the axial direction, see in particular fig. 2. In this way, the flue gases generated in the internal combustion space can be better entrained outside the burner and thus facilitate their subsequent suction into the second combustion air channel.

In addition, in order to control the oxygen content involved in combustion more precisely, a damper structure 171 may be provided at the combustion air inlet of the first combustion air passage 170, or a damper structure 182 may be provided at the center wind duct 181 of the second combustion air passage 180 as well. Here, the combustion air quantity involved in the external second combustion process is approximately the sum of the combustion air quantities through the center duct 181 and the ejector 151. It should be understood that the concept of "combustion air" refers to a combustion gas for promoting combustion of gas and is not limited to the gas form now described, which may be, for example, air.

In a further alternative embodiment, a mounting plate 190 is also arranged between the refractory bricks 110 and the underlying bellows 120, wherein the refractory bricks 110 are fastened with their bases to the mounting plate 190 by means of brackets (not shown) and the bellows 120 can be fastened to the mounting plate 190, for example by means of screws. The mounting plate 190 is provided with a through hole, and the first gas passage 111 and the second gas passage 121 are connected to each other through the through hole. A space exists between the bottom of the refractory brick 110 and the mounting plate 190 and thus the injector tube 151 may be disposed between the mounting plate 190 and the bottom of the refractory brick 110. Specifically, the ejector tube 151 is laterally inserted with its ejector outlet into the central air duct 181 and is optionally welded with its outer wall to the wall of the central air duct 181.

In another alternative embodiment, the combustor 100 also has a sleeve 191 that is made of an insulating material and may be referred to as an insulating sleeve. The sleeve 191 partially encloses the refractory block 110, and in particular, the lower portion of the refractory block 110, and is supported and secured with its bottom to the mounting plate 190. In the assembled state, the sleeve covers the ejector tube 151 and the ejector gun 152 associated therewith, so that it is protected from damage due to excessive temperatures. As shown in fig. 1, a plurality of through holes, in particular as many as the injection lances 152, are provided in the peripheral wall of the sleeve 191, through which the flue gas is drawn into the second combustion air channel 180 during operation of the burner due to the negative pressure generated by the venturi tube. The thermal sleeve may be integrally formed with the refractory brick, for example, may be made of a refractory material; or both may be separate and separately secured at the mounting plate.

Finally, the operation of the burner 100 is explained according to the embodiment shown in the drawings. The gas is supplied to the first gas lance 130 located inside the first gas passage and the second gas lance 140 located outside the refractory brick through a gas pipe 160 communicating with a gas source. Meanwhile, the combustion air is supplied to the hollow cylindrical inner combustion space through the first combustion air passage 170 to participate in the first combustion process in the inner combustion space. The combustion air is supplied to the external combustion space above the burner through the second combustion air passage 180 and the center air duct 181, and in addition, a part of the combustion air is injected into the center air duct 181 through the injection lance 152 and the injection pipe 151 to participate in the second combustion process of the outside together. During this time, the flue gases from the combustion pass through the sleeve 191, the ejector tube 151, the central air duct 181 in sequence and thereby affect the second combustion process in the outer combustion space.

In summary, the burner according to the utility model reduces the structural complexity of the relevant mechanisms for internal recirculation of flue gases and thus achieves lower NO _X emissions. In one embodiment, the structural complexity of the burner can be further reduced by adding a venturi. In another embodiment, by retrofitting the first and second combustion air channels (in particular the central duct), the inner and outer combustion spaces can be optimized and thus the combustion process can be further optimized. In another embodiment, the space utilization of the burner can be further optimized by modifying the spatial arrangement of the ejector tube.

It should be understood that all of the above preferred embodiments are exemplary and not limiting, and that various modifications or variations of the above-described specific embodiments, which are within the spirit of the utility model, should be made by those skilled in the art within the legal scope of the utility model.

Claims

1. A burner, comprising:

a refractory brick in which a first gas passage is opened;

2. The burner of claim 1, wherein the negative pressure flue gas return means comprises an ejector tube and an ejector lance for ejecting ejector gas into the ejector tube, the ejector tube leading to the outside of the burner at one end thereof and to the second combustion air passage at the other end thereof, wherein the ejector tube is of venturi construction.

3. The burner of claim 2, wherein the injection gas is compressed combustion air, compressed nitrogen, or compressed inert gas.

4. The burner of claim 2 wherein the first combustion air passage and the second combustion air passage are in communication with the same combustion air source.

5. The burner of claim 2, wherein the second combustion air passage includes a central air duct passing through the first gas passage in an axial direction to deliver combustion air into an external space above the refractory bricks, wherein the ejector tube opens into the central air duct to draw flue gas into the central air duct.

6. The burner of claim 5, wherein the combustion air outlet of the center duct is flush with the top of the first gas passage.

7. The burner of claim 5, wherein the center barrel also passes through the second gas passage in the axial direction, wherein a first clearance space exists between the outer wall of the center barrel and the wall portion of the first gas passage, a gas outlet of the first gas lance is arranged in the first clearance space, and a second clearance space exists between the outer wall of the center barrel and the wall portion of the second gas passage, the first combustion air passage opening into the second clearance space.

8. The burner of claim 2, further comprising a mounting plate, the refractory bricks being secured at the mounting plate, and the injector tube being disposed between the refractory bricks and the mounting plate.

9. The burner of claim 8, further comprising a sleeve secured to the mounting plate, the sleeve surrounding a lower portion of the refractory brick and having a plurality of through holes formed in a peripheral wall of the sleeve through which flue gas is directed into the ejector tube.

10. Burner according to any of claims 1 to 9, characterized in that a damper structure is provided at the combustion air inlet of the first combustion air channel or at the combustion air inlet of the second combustion air channel for adjusting the amount of inflowing combustion air.