Premixing device and burner

Abstract

The present invention relates to a premixing device and a burner thereof, wherein the premixing device comprises: an air chamber, a fuel chamber, a fuel dispersion pipe and a nozzle, wherein the air chamber is provided with an air inlet, the fuel chamber is arranged circumferentially around the air chamber, the fuel chamber is provided with a fuel inlet, the fuel dispersion pipe and the nozzle are both multiple, the multiple fuel dispersion pipes are connected to the fuel chamber, each nozzle is connected to a plurality of the fuel dispersion pipes, the multiple nozzles are arranged at intervals along the circumference of the fuel chamber, one end of the nozzle is connected to the air chamber, and the other end of the nozzle has an outlet for spraying mixed gas. The premixing device of the present invention can fully mix the fuel and the air, with a low probability of backfire and high safety.

Description

Technical Field

[0001] The present invention relates to the technical field of burners, and in particular to a premixing device and a burner thereof. Background Art

[0002] With the continuous growth of global energy demand and the frequent occurrence of extreme weather, it is urgent to develop clean, low-carbon and renewable energy and reduce greenhouse gas emissions. In order to further reduce the emission of greenhouse gases such as carbon dioxide and improve combustion efficiency, it is crucial to explore sustainable energy supply channels in the power generation, industry and transportation sectors. In this context, hydrogen has been widely studied as a good energy carrier. For example, blending a high proportion of hydrogen into natural gas for hydrogen-rich blending and pure hydrogen combustion is an important application approach.

[0003] In the relevant technology, there are significant challenges in the combustion and utilization of rich hydrogen and pure hydrogen. On the one hand, the flame propagation speed of hydrogen is extremely high, the flame distance is shorter, and there is a risk of ablation in the combustion nozzle. On the other hand, hydrogen has a wide flammable range and a fast flame propagation speed, and it is very easy to flash back under the traditional premixed combustion method. In addition, the thermoacoustic amplitude level and frequency of hydrogen combustion are different from those of traditional natural gas. Traditional natural gas burners used for high-proportion hydrogen combustion may have unstable and insufficient combustion, and lead to more pollutant emissions, and reduce the safety of burner use. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, an embodiment of the present invention proposes a premixing device that can fully mix fuel and air, has a low probability of backfire, and is safer.

[0006] An embodiment of the present invention further provides a burner.

[0007] The premixing device of an embodiment of the present invention includes: an air chamber, which is provided with an air inlet; a fuel chamber, which is arranged circumferentially around the air chamber and is provided with a fuel inlet; a fuel dispersion pipe and a nozzle, wherein there are multiple fuel dispersion pipes and nozzles, and the multiple fuel dispersion pipes are connected to the fuel chamber, each of the nozzles is connected to several fuel dispersion pipes, and the multiple nozzles are arranged at intervals along the circumference of the fuel chamber, one end of the nozzle is connected to the air chamber, and the other end of the nozzle has an outlet hole for spraying the mixed gas.

[0008] According to the premixing device of the embodiment of the present invention, air can enter the air chamber from the air inlet. Since one end of the nozzle is connected to the air chamber, the air in the air chamber can be dispersed and passed into multiple nozzles. Fuel can enter the fuel chamber from the fuel inlet. Since the fuel chamber is connected to the nozzle through multiple fuel dispersion pipes, the fuel can be dispersed into the nozzle through the fuel dispersion pipes and mixed with the air in the nozzle, and finally discharged from the air outlet. Therefore, the premixing device of the embodiment of the present invention can fully mix the fuel and air, reduce the probability of backfire, and has higher safety.

[0009] In some embodiments, the fuel chamber includes a feed chamber and multiple fuel distribution chambers, the feed chamber is provided with the fuel inlet and is connected to the multiple fuel distribution chambers, the multiple fuel distribution chambers are all annular, the axes of the multiple fuel distribution chambers are parallel and nested with each other, the nozzle is provided between two adjacent fuel distribution chambers, and the fuel dispersion pipe is connected to the nozzle and the fuel distribution chamber.

[0010] In some embodiments, the fuel distribution chamber includes at least a first distribution chamber and a second distribution chamber, the second distribution chamber is arranged on the inner side of the first distribution chamber, part of the nozzle is arranged between the first distribution chamber and the second distribution chamber, and is arranged circumferentially around the first distribution chamber, and the fuel dispersion pipe includes a first dispersion pipe and a second dispersion pipe, one end of the first dispersion pipe is connected to the first distribution chamber, and the other end of the first dispersion pipe is connected to the nozzle, one end of the second dispersion pipe is connected to the second distribution chamber, and the other end of the second dispersion pipe is connected to the nozzle.

[0011] In some embodiments, the premixing device further comprises a plurality of main fuel distribution pipes, which are disposed between the first distribution chamber and the second distribution chamber and are spaced apart along the circumference of the first distribution chamber. One end of the main fuel distribution pipe is connected to the first distribution chamber, and the other end of the main fuel distribution pipe is connected to the second distribution chamber. The feed chamber is connected to the outermost fuel distribution chamber.

[0012] In some embodiments, the first dispersing pipe and the second dispersing pipe communicated with the same nozzle are arranged opposite to each other along the radial direction of the nozzle.

[0013] In some embodiments, some of the fuel dispersion pipes are spaced apart along the axial direction of the nozzle, and a spacing between the fuel dispersion pipes along the axial direction of the nozzle is greater than or equal to 5 mm and less than or equal to 15 mm.

[0014] In some embodiments, the inner diameter of the fuel dispersion pipe is greater than or equal to 0.1 mm and less than or equal to 0.5 mm.

[0015] In some embodiments, the inner diameter of the nozzle is greater than or equal to 6 mm and less than or equal to 12 mm; and / or, the length of the nozzle is greater than or equal to 20 mm and less than or equal to 100 mm; and / or, the spacing between two adjacent nozzles is greater than or equal to 5 mm and less than or equal to 60 mm.

[0016] In some embodiments, the distance between the fuel distribution pipe closest to the air outlet and the air outlet is greater than or equal to 25 mm and less than or equal to 100 mm; and / or, the nozzle has an air inlet hole connected to the air chamber, and the distance between the fuel distribution pipe closest to the air inlet hole and the air inlet hole is greater than or equal to 15 mm and less than or equal to 35 mm.

[0017] A burner according to another embodiment of the present invention comprises the premixing device described in any one of the embodiments of the present invention.

[0018] According to the burner of the embodiment of the present invention, air can enter the air chamber from the air inlet. Since one end of the nozzle is connected to the air chamber, the air in the air chamber can be dispersed and passed into multiple nozzles; fuel can enter the fuel chamber from the fuel inlet. Since the fuel chamber is connected to the nozzle through a plurality of fuel dispersion pipes, the fuel can be dispersed into the nozzle through the fuel dispersion pipes and mixed with the air in the nozzle, and finally discharged from the air outlet. Therefore, the premixing device of the burner of the embodiment of the present invention can fully mix the fuel and the air, reduce the probability of flashback, and have higher safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 1 is an isometric view of a premixing device according to an embodiment of the present invention.

[0020] Figure 2 It is an isometric view from another perspective of the premixing device of the embodiment of the present invention.

[0021] Figure 3 It is a front view of the premixing device according to an embodiment of the present invention.

[0022] Figure 4 yes Figure 3 Cross-sectional view of AA.

[0023] Figure 5 2 is a cross-sectional view of a premixing device according to an embodiment of the present invention.

[0024] Figure 6 2 is a side view of a premixing device according to an embodiment of the present invention.

[0025] Reference numerals:

[0026] 1. Air chamber; 11. Air inlet;

[0027] 2. Fuel chamber; 21. Feed chamber; 211. Fuel inlet; 22. Fuel distribution chamber; 221. First distribution chamber; 222. Second distribution chamber; 223. Third distribution chamber;

[0028] 3. fuel dispersion pipe; 31. first dispersion pipe; 32. second dispersion pipe;

[0029] 4. Nozzle; 41. Air inlet; 42. Air outlet;

[0030] 5. Fuel distribution supervisor. DETAILED DESCRIPTION

[0031] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0032] Please refer to the following Figures 1 to 6 A premixing device and a burner thereof according to an embodiment of the present invention are described.

[0033] like Figures 1 to 6 As shown, the premixing device according to the embodiment of the present invention comprises: an air chamber 1, a fuel chamber 2, a fuel dispersion pipe 3 and a nozzle 4. The air chamber 1 is provided with an air inlet 11, the fuel chamber 2 is arranged around the circumference of the air chamber 1, the fuel chamber 2 is provided with a fuel inlet 211, the fuel dispersion pipe 3 and the nozzle 4 are both multiple, the multiple fuel dispersion pipes 3 are connected to the fuel chamber 2, each nozzle 4 is connected to a plurality of fuel dispersion pipes 3, the multiple nozzles 4 are arranged at intervals along the circumference of the fuel chamber 2, one end of the nozzle 4 is connected to the air chamber 1, and the other end of the nozzle 4 has an outlet hole 42 for spraying the mixed gas.

[0034] It can be understood that the fuel chamber 2 can be arranged around the inner periphery of the air chamber 1, or around the outer periphery of the air chamber 1. In the example of the present application, the fuel chamber 2 is arranged around the outer periphery of the air chamber 1.

[0035] For example, the fuel chamber 2 and the air chamber 1 are located on the same axis and are in a double-layer sleeve-like structure. The fuel inlet 211 is located at one end of the fuel chamber 2 in the axial direction, the air inlet 11 is located at one end of the air chamber 1 in the axial direction, and the fuel inlet 211 and the fuel outlet are located on the same side of the premixing device, thereby facilitating the connection of the premixing device with an external fuel source and air source.

[0036] According to the premixing device of the embodiment of the present invention, air can enter the air chamber 1 through the air inlet 11, and since one end of the nozzle 4 is connected to the air chamber 1, the air in the air chamber 1 can be dispersed and passed into multiple nozzles 4; fuel can enter the fuel chamber 2 through the fuel inlet 211, and since the fuel chamber 2 is connected to the nozzle 4 through multiple fuel dispersion pipes 3, the fuel can be dispersed into the nozzle 4 through the fuel dispersion pipes 3, and mixed with the air in the nozzle 4, and finally discharged from the air outlet 42. Therefore, the premixing device of the embodiment of the present invention can fully mix the fuel and the air, reduce the probability of backfire, and has higher safety.

[0037] The inventors of the present application have found through experimental research that when the fuel is hydrogen-rich / pure hydrogen, the mixing effect of the fuel and the air can be significantly improved to ensure lower NOx emissions. That is, the fuel and the air can be strongly mixed in the premixing device, which plays an important role in reducing NOx emissions and effectively avoids the risk of flashback in a hydrogen-rich environment.

[0038] Of course, the premixing device of the embodiment of the present invention can also be applied to fuels such as natural gas and liquefied gas, and the present application does not specifically limit the fuel introduced into the premixing device.

[0039] In other words, the plurality of nozzles 4 are arranged at intervals along the circumference of the fuel chamber 2, and the wall of each nozzle 4 is connected to the fuel chamber 2 through a plurality of fuel dispersion tubes 3, so that the fuel in the fuel chamber 2 can be dispersed into each nozzle 4 through the fuel dispersion tubes 3. Since one end of the nozzle 4 is connected to the air chamber 1, the air entering the nozzle 4 can be mixed with the fuel entering the nozzle 4, and then discharged through the air outlet 42 at the other end of the nozzle 4.

[0040] In some embodiments, the fuel chamber 2 includes a feed chamber 21 and a plurality of fuel distribution chambers 22. The feed chamber 21 is provided with a fuel inlet 211 and is connected to the plurality of fuel distribution chambers 22. The plurality of fuel distribution chambers 22 are all annular, and the axes of the plurality of fuel distribution chambers 22 are parallel and mutually nested. The nozzle 4 is provided between two adjacent fuel distribution chambers 22, and the fuel dispersion pipe 3 is connected to the nozzle 4 and the fuel distribution chamber 22. It can be understood that after the fuel enters the feed chamber 21, it can be dispersed into each fuel distribution chamber 22, and then passed into the nozzle 4 between two adjacent fuel distribution chambers 22 through the fuel dispersion pipe 3, thereby further dispersing the fuel and improving the premixing effect of the premixing device.

[0041] For example, the feed chamber 21 may be connected to the outermost fuel distribution chamber 22, one axial end of the feed chamber 21 is provided with a fuel inlet 211, and the other axial end of the feed chamber 21 is connected to the outermost fuel distribution chamber 22. Adjacent fuel distribution chambers 22 are connected to each other through the fuel dispersion pipe 3.

[0042] Optionally, the plurality of nozzles 4 may be arranged in an orthogonal array, a square array or a circular array. For example, the nozzles 4 are arranged in multiple circles from the inside to the outside. In other words, one or more circles of nozzles 4 are arranged between each two adjacent fuel distribution chambers 22.

[0043] In a specific example, the fuel distribution chamber 22 at least includes a first distribution chamber 221 and a second distribution chamber 222, the second distribution chamber 222 is arranged inside the first distribution chamber 221, part of the nozzle 4 is arranged between the first distribution chamber 221 and the second distribution chamber 222, and is arranged circumferentially around the first distribution chamber 221, and the fuel dispersion pipe 3 includes a first dispersion pipe 31 and a second dispersion pipe 32, one end of the first dispersion pipe 31 is connected to the first distribution chamber 221, the other end of the first dispersion pipe 31 is connected to the nozzle 4, one end of the second dispersion pipe 32 is connected to the second distribution chamber 222, and the other end of the second dispersion pipe 32 is connected to the nozzle 4. It can be understood that the first distribution chamber 221 is the outermost fuel distribution chamber 22, the feed chamber 21 is connected to the first distribution chamber 221, and the first distribution chamber 221, the first dispersion pipe 31, the nozzle 4 (between the first distribution chamber 221 and the second distribution chamber 222), the second dispersion pipe 32 and the second distribution chamber 222 are connected in sequence. This allows the fuel and air to be mixed in stages and strata, so as to further improve the uniformity of the premixing of the fuel and air.

[0044] In order to improve the flow efficiency of fuel between adjacent fuel distribution chambers 22, the premixing device also includes a plurality of fuel main distribution pipes, which are arranged between the first distribution chamber 221 and the second distribution chamber 222 and are arranged at intervals along the circumference of the first distribution chamber 221. One end of the fuel main distribution pipe is connected to the first distribution chamber, and the other end of the fuel main distribution pipe is connected to the second distribution chamber. It can be understood that the diameter of the fuel main distribution pipe is thicker than the diameter of the fuel dispersion pipe 3, so that the fuel can be quickly distributed to each fuel distribution chamber 22 to achieve stratified and graded mixing of fuel and air.

[0045] Specifically, the fuel distribution chamber 22 also includes a third distribution chamber 223, which is arranged on the inner periphery of the second distribution chamber 222 and is separated from the second distribution chamber 222. It can be understood that the connection mode between the second distribution chamber 222 and the third distribution chamber 223 is similar to the connection mode between the first distribution chamber 221 and the second distribution chamber 222. That is, a circle of nozzles 4 is also arranged between the second distribution chamber 222 and the third distribution chamber 223, and fuel is also transmitted between the second distribution chamber 222 and the third distribution chamber 223 through the fuel main distribution pipe and the fuel dispersion pipe 3. In this way, the uniformity of the premixing of fuel and air can be further improved.

[0046] In other examples, an independent fuel inlet 211 is provided at one axial end of each fuel distribution chamber 22, that is, fuels of multiple different components can be introduced into each fuel distribution chamber 22 respectively without affecting each other. Thus, multiple fuels of different components can be mixed in one premixing device at the same time, significantly expanding the application range of the premixing device for fuels.

[0047] In some embodiments, the first dispersion pipe 31 and the second dispersion pipe 32 connected to the same nozzle 4 are arranged opposite to each other along the radial direction of the nozzle 4. It can be understood that the pipe opening of the first dispersion pipe 31 and the pipe opening of the second dispersion pipe 32 are arranged opposite to each other, thereby the fuel entering the nozzle 4 can be dispersed to improve the premixing effect of the fuel and the air.

[0048] Optionally, some fuel dispersion pipes 3 are arranged at intervals along the axial direction of the nozzle 4, and the interval between the fuel dispersion pipes 3 along the axial direction of the nozzle 4 is greater than or equal to 5 mm and less than or equal to 15 mm. Further, the inner diameter of the fuel dispersion pipe 3 is greater than or equal to 0.1 mm and less than or equal to 0.5 mm.

[0049] For example, 2-6 groups of fuel dispersion tubes 3 may be provided, and the spacing of the fuel dispersion tubes 3 along the axial direction of the nozzle 4 is 5 mm, 8 mm, 10 mm, 12 mm, or 15 mm. The inventor of the present application has found through experimental research that the spacing of the fuel dispersion tubes 3 along the axial direction of the nozzle 4 in the above parameter range is conducive to more complete mixing of the air and fuel in the nozzle 4.

[0050] It is understandable that the inner diameter of the fuel dispersion tube 3 of 0.1-0.5 mm can ensure that the ratio of the fuel jet momentum to the air jet momentum is in a better momentum ratio range, so as to achieve the best uniform mixing of the fuel and the air. In addition, the more groups of dispersion tubes there are, the more graded mixing of the fuel can be achieved, which plays an important role in the uniform mixing of the fuel and the air. However, the more groups the better, and the appropriate fuel jet momentum must also be ensured. Therefore, the spacing between adjacent fuel dispersion tubes 3 is designed to be 5-15 mm, which can provide a suitable mixing space for the fuel sprayed from each group of fuel dispersion tubes 3 and the air to mix, so as to improve the mixing effect.

[0051] Optionally, the inner diameter of the nozzle 4 is greater than or equal to 6 mm and less than or equal to 12 mm, and the length of the nozzle 4 is greater than or equal to 20 mm and less than or equal to 100 mm. Among them, the inner diameter of the nozzle 4 is designed to be 6-12 mm, which can effectively prevent the flashback of the hydrogen-rich / pure hydrogen flame on the one hand, and on the other hand, it can ensure that the internal flow state is turbulent flow, thereby improving the mixing effect. The length of the nozzle 4 is designed to be 20-100 mm, which can effectively ensure that the fuel and air can be evenly mixed in the premixing device, thereby ensuring lower NOx emissions. In addition, the nozzle 4 adopts the above-mentioned micro-mixing tube with a smaller inner diameter, which is to strengthen the strong mixing of fuel and air in a micro environment, which plays an important role in reducing NOx emissions. At the same time, it also effectively avoids the risk of flashback in a hydrogen-rich environment.

[0052] The spacing between two adjacent nozzles 4 is greater than or equal to 5 mm and less than or equal to 60 mm. The inventor of the present application has found through experimental research that the spacing between two adjacent nozzles 4 cannot be too small, otherwise it is easy to cause the phenomenon of concentrated combustion flames, excessively high combustion temperatures, and excessively high NOx emissions. Of course, the spacing between two adjacent nozzles 4 cannot be too large, otherwise it is difficult to form a stable combustion flame. Therefore, the embodiment of the present application uses the above-mentioned parameter design for the spacing between two adjacent nozzles 4, which can both reduce NOx emissions and form a stable combustion flame.

[0053] Optionally, the distance between the fuel dispersion tube 3 closest to the air outlet 42 and the air outlet 42 is greater than or equal to 25 mm and less than or equal to 100 mm, the nozzle 4 has an air inlet 41 connected to the air chamber 1, and the distance between the fuel dispersion tube 3 closest to the air inlet 41 and the air inlet 41 is greater than or equal to 15 mm and less than or equal to 35 mm, thereby allowing the air flow to fully develop in the nozzle 4 to ensure the premixing effect of fuel and air.

[0054] Optionally, the extension direction of the nozzle 4 may be parallel to or have a certain angle with the axial direction of the air chamber 1 or the fuel chamber 2. For example, the extension direction of the nozzle 4 may have an angle of 0-60° with the axial direction of the air chamber 1 or the fuel chamber 2 to meet the use requirements of most burners.

[0055] A burner according to another embodiment of the present invention comprises the premixing device of the present invention.

[0056] According to the burner of the embodiment of the present invention, air can enter the air chamber 1 through the air inlet 11. Since one end of the nozzle 4 is connected to the air chamber 1, the air in the air chamber 1 can be dispersed and passed into multiple nozzles 4; fuel can enter the fuel chamber 2 through the fuel inlet 211. Since the fuel chamber 2 is connected to the nozzle 4 through multiple fuel dispersion pipes 3, the fuel can be dispersed into the nozzle 4 through the fuel dispersion pipes 3 and mixed with the air in the nozzle 4, and finally discharged from the air outlet 42. Therefore, the premixing device of the burner of the embodiment of the present invention can fully mix the fuel and the air, reduce the probability of flashback, and have higher safety.

[0057] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0058] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0059] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0060] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0061] In the present invention, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0062] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. A premixing device, characterized in that: include: An air chamber, wherein the air chamber is provided with an air inlet; A fuel chamber, the fuel chamber is arranged around the circumference of the air chamber, the fuel chamber is provided with a fuel inlet, and the fuel is hydrogen-rich or pure hydrogen fuel; A fuel dispersion pipe and a nozzle, wherein the fuel dispersion pipe and the nozzle are multiple, the multiple fuel dispersion pipes are connected to the fuel chamber, each nozzle is connected to a plurality of the fuel dispersion pipes, the multiple nozzles are arranged at intervals along the circumference of the fuel chamber, one end of the nozzle is connected to the air chamber, and the other end of the nozzle has an outlet hole for spraying the mixed gas; The fuel chamber comprises a feed chamber and a plurality of fuel distribution chambers, the feed chamber is provided with the fuel inlet and is connected with the plurality of fuel distribution chambers, the plurality of fuel distribution chambers are annular, the axes of the plurality of fuel distribution chambers are parallel and mutually nested, the nozzle is provided between two adjacent fuel distribution chambers, and the fuel dispersion pipe is connected with the nozzle and the fuel distribution chamber; The fuel distribution chamber at least includes a first distribution chamber and a second distribution chamber, the second distribution chamber is arranged inside the first distribution chamber, part of the nozzle is arranged between the first distribution chamber and the second distribution chamber, and is arranged at intervals around the circumference of the first distribution chamber, the fuel dispersion pipe includes a first dispersion pipe and a second dispersion pipe, one end of the first dispersion pipe is connected to the first distribution chamber, the other end of the first dispersion pipe is connected to the nozzle, one end of the second dispersion pipe is connected to the second distribution chamber, the other end of the second dispersion pipe is connected to the nozzle, the first dispersion pipe and the second dispersion pipe connected to the same nozzle are arranged opposite to each other along the radial direction of the nozzle, and the inner diameter of the fuel dispersion pipe is greater than or equal to 0.1 mm and less than or equal to 0.5 mm; It also includes a plurality of main fuel distribution pipes, which are arranged between the first distribution chamber and the second distribution chamber and are spaced apart along the circumference of the first distribution chamber. One end of the main fuel distribution pipe is connected to the first distribution chamber, and the other end of the main fuel distribution pipe is connected to the second distribution chamber. The feed chamber is connected to the outermost fuel distribution chamber.

2. The premixing device according to claim 1, characterized in that: Some of the fuel dispersion pipes are arranged at intervals along the axial direction of the nozzle, and the interval between the fuel dispersion pipes along the axial direction of the nozzle is greater than or equal to 5 mm and less than or equal to 15 mm.

3. The premixing device according to claim 1, characterized in that: The inner diameter of the nozzle is greater than or equal to 6 mm and less than or equal to 12 mm; And / or, the length of the nozzle is greater than or equal to 20 mm and less than or equal to 100 mm; And / or, the distance between two adjacent nozzles is greater than or equal to 5 mm and less than or equal to 60 mm.

4. The premixing device according to claim 1, characterized in that: The distance between the fuel dispersing pipe closest to the gas outlet and the gas outlet is greater than or equal to 25 mm and less than or equal to 100 mm; And / or, the nozzle has an air inlet hole connected to the air chamber, and the distance between the fuel distribution pipe closest to the air inlet hole and the air inlet hole is greater than or equal to 15 mm and less than or equal to 35 mm.

5. A burner, characterized in that: The invention comprises the premixing device according to any one of claims 1 to 4.

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