A combined biomass gas burner

Abstract

A combined biomass gas burner provided by the present invention includes an air supply pipeline, a biomass gas supply pipeline, an igniter, an air swirler, a tar dispersion plate, and a combustion mixing flower plate. A biomass gas supply pipeline and an igniter are coaxially arranged in the air supply pipeline. An air swirler is coaxially arranged at the outer ring outlet of the air supply pipeline. There is a gap between the air swirler and the biomass gas supply pipeline. A tar dispersion plate is arranged at the central outlet of the air supply pipeline. A combustion mixing flower plate is arranged on the tar dispersion plate. The combustion mixing flower plate is evenly provided with holes for evenly dispersing and distributing the mixed gas and assisting in full combustion. The inclination angle of the air swirler blades in the outer ring pipeline of the air supply pipeline is between 30° and 45°, and the dispersion angle of the tar dispersion plate is between 110° and 130°. By reasonably controlling the mixing of air and biomass gas, the combustion efficiency is improved, the nitrogen emission is reduced, and the environmental pollution is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of low-nitrogen combustion of biomass gas, and particularly relates to a combined biomass gas burner. Background Art

[0002] With the green transformation of the energy structure and the proposal of the carbon neutrality goal, biomass energy is the fourth energy source after fossil energy, natural energy (solar energy, tides, wind energy, etc.) and nuclear energy. Biomass is inexhaustible and renewable. Biomass energy has the characteristics of high volatile content, low ash content, low sulfur content, etc. Since the growth environment absorbs CO 2 , 2 , 2 amount equivalent to the CO 2 emitted during combustion, the net CO 2 emission during the energy conversion process is approximately zero, which is beneficial to improving the greenhouse effect. Research and development of technologies for efficient utilization of biomass energy, conservation of conventional fossil energy, and optimization of the energy structure are of great significance. Biomass gas is a combustible gas generated by gasifiers from crop straws and forestry waste, and it is a way for the development of biomass energy towards large-scale industrial applications. Currently, biomass gas burners are gradually being promoted and utilized.

[0003] Due to the characteristics of biomass gas itself, most biomass gas generally has a high tar content and cannot be fully cracked. It burns incompletely in existing burners, resulting in a reduction in combustion efficiency and easy environmental pollution. At the same time, due to incomplete combustion in existing burners, the generation amount of nitrogen oxides during the combustion process of biomass gas is difficult to meet the ultra-low nitrogen emission requirements, causing serious environmental pollution problems; at the same time, the resistance of the burner channel is slightly large, which will cause rapid accumulation of tar, easily cause tar blockage of the burner, and is very difficult to clean. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a combined biomass gas burner, which improves the combustion efficiency, reduces nitrogen emissions, and reduces environmental pollution.

[0005] The present invention is achieved through the following technical solutions:

[0006] A combined biomass gas burner includes an air supply pipeline, a biomass gas supply pipeline, an igniter, an air swirler, a tar dispersion plate, and a combustion mixing flower plate. The biomass gas supply pipeline and the igniter are coaxially arranged in the air supply pipeline. An air swirler is coaxially arranged at the outer outlet of the air supply pipeline. There is a gap between the air swirler and the biomass gas supply pipeline. A tar dispersion plate is arranged at the central outlet of the air supply pipeline. A combustion mixing flower plate is arranged on the tar dispersion plate. The combustion mixing flower plate is evenly provided with holes for evenly dispersing and distributing the mixed gas and assisting in full combustion. The inclination angle of the air swirler blades in the outer pipeline of the air supply pipeline is between 30° and 45°, and the dispersion angle of the tar dispersion plate is between 110° and 130°.

[0007] The air supply pipeline mentioned above includes a primary air duct, a primary air inlet pipeline, and a central air duct. An air swirler is installed at the outlet of the primary air duct. A primary air inlet pipeline is arranged on the primary air duct. The central air duct is coaxially arranged in the primary air duct. A tar dispersion plate is arranged at the outlet of the central air duct.

[0008] The biomass gas supply pipeline includes a biomass gas inlet pipeline and a biomass gas pipe. The biomass gas inlet pipeline is connected to the biomass gas pipe. There is a gap between the air swirler and the biomass gas pipe. The biomass gas pipe is arranged in the primary air duct. The central air duct is arranged in the center of the biomass gas pipe. The igniter is arranged in the central air duct. The primary air duct, the central air duct, the biomass gas pipe, the igniter, and the air swirler are coaxially arranged.

[0009] The inclination angle of the blades of the air swirler in the primary air duct is between 30° and 45°.

[0010] The diameter ratio of the primary air duct to the biomass gas pipe is 5:4.

[0011] There is a gap of 4 - 6 mm between the air swirler and the biomass gas pipe.

[0012] There is a gap of 5 mm between the air swirler and the biomass gas pipe.

[0013] The dispersion angle of the tar dispersion plate is 120°.

[0014] As mentioned above, a tar dispersion plate is arranged at the outlet of the central air duct through a connecting plate, and the tar dispersion plate is connected to the combustion mixing flower plate through a fixing plate.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects:

[0016] The combined biomass gas burner provided by the present invention is used to solve the problem that the generation amount of nitrogen oxides during the combustion of biomass gas is difficult to meet the requirements of ultra-low nitrogen emissions; the burner includes an air supply pipeline, a biomass gas supply pipeline, a tar dispersion plate, and a combustion mixing flower plate. Among them, the primary air duct, the central air duct, the biomass gas duct, the igniter, and the air swirler are coaxially arranged; the tar dispersion plate and the combustion mixing flower plate are arranged at the outlet of the biomass gas duct, and there is a gap between the air swirler and the primary air duct; through fuel staging combustion, swirl combustion, and dispersed jet combustion technologies, the mixing of air and biomass gas is reasonably controlled, so that the biomass gas fully reacts with oxygen in the boiler, burns out the tar, improves the combustion efficiency, prevents tar from coking in the burner and the boiler, reduces the cleaning workload, and at the same time reduces the environmental pollution, achieving the purpose of low NOx combustion of the gas.

[0017] The combined biomass gas burner provided by the present invention solves the problem that the generation amount of nitrogen oxides during the combustion of biomass gas is difficult to meet the requirements of ultra-low nitrogen emissions and causes serious environmental pollution; reasonably controls the mixing of air and biomass gas, so that the biomass gas fully reacts with oxygen in the boiler, burns out the tar, improves the combustion efficiency, prevents tar from coking in the burner and the boiler, reduces the cleaning workload, and at the same time reduces the environmental pollution. Brief Description of the Drawings

[0018] Figure 1 It is a schematic cross-sectional view of the combined biomass gas burner provided by the present invention;

[0019] Figure 2 It is a schematic diagram of the combined biomass gas burner provided by the present invention.

[0020] Among them, 1 is the primary air duct; 2 is the primary air inlet pipeline; 3 is the central air duct; 4 is the igniter; 5 is the biomass gas inlet pipeline; 6 is the biomass gas duct; 7 is the air swirler; 8 is the connecting plate; 9 is the tar dispersion plate; 10 is the combustion mixing flower plate; 11 is the fixing plate. Detailed Description of the Invention

[0021] The following further elaborates on the present invention in detail with specific embodiments, which is an explanation rather than a limitation of the present invention.

[0022] See Figures 1 to 2, a combined biomass gas burner, comprising an air supply pipeline, a biomass gas supply pipeline, an igniter 4, an air swirler 7, a tar dispersion plate 9 and a combustion mixing flower plate 10; in the air supply pipeline, a biomass gas supply pipeline and an igniter 4 are coaxially arranged, an air swirler 7 is coaxially arranged at the outer ring outlet of the air supply pipeline, a gap is left between the air swirler 7 and the biomass gas supply pipeline, a tar dispersion plate 9 is arranged at the central outlet of the air supply pipeline, a combustion mixing flower plate 10 is arranged on the tar dispersion plate 9, and holes for uniformly dispersing and distributing the mixed gas and assisting in full combustion are evenly arranged on the combustion mixing flower plate 10. The inclination angle of the blades of the air swirler 7 in the outer ring pipeline of the air supply pipeline is between 30° and 45°, and the dispersion angle of the tar dispersion plate 9 is 110° - 130°.

[0023] Specifically, the air supply pipeline includes a primary air duct 1, a primary air inlet pipeline 2 and a central air duct 3; an air swirler 7 is installed at the outlet of the primary air duct 1, a primary air inlet pipeline 2 is arranged on the primary air duct 1, a central air duct 3 is coaxially arranged in the primary air duct 1, and a tar dispersion plate 9 is arranged at the outlet of the central air duct 3 through a connecting plate 8. The tar dispersion plate 9 is connected to the combustion mixing flower plate 10 through a fixing plate 11; the biomass gas supply pipeline includes a biomass gas inlet pipeline 5 and a biomass gas pipe 6; the biomass gas inlet pipeline 5 is connected to the biomass gas pipe 6, and a gap of 4 - 6 mm is left between the air swirler 7 and the biomass gas pipe 6; the biomass gas pipe 6 is arranged in the primary air duct 1, the central air duct 3 is arranged in the center of the biomass gas pipe 6, an igniter 4 is arranged in the central air duct 3, and the primary air duct 1, the central air duct 3, the biomass gas pipe 6, the igniter 4 and the air swirler 7 are coaxially arranged; the inclination angle of the blades of the air swirler 7 in the primary air duct 1 is between 30° and 45°, and the diameter ratio of the primary air duct 1 to the biomass gas pipe 6 is 5:4.

[0024] Preferably, a gap of 5 mm is left between the air swirler 7 and the biomass gas pipe 6, and the dispersion angle of the tar dispersion plate 9 is 120°.

[0025] Embodiment 2

[0026] A combined biomass gas burner, comprising an air supply pipeline, a biomass gas supply pipeline, a tar dispersion plate 9, a combustion mixing flower plate 10, an igniter 4 and an air swirler 7;

[0027] The air supply pipeline includes a primary air duct 1, a primary air inlet duct 2, and a central air duct 3; the air swirler 7 is installed at the outlet of the primary air duct 1, and there is a gap between the air swirler 7 and the biomass gas duct 6; the tar dispersion plate 9 is connected to the central air duct 3 through a connecting plate 8 at the outlet of the central air duct 3, and the combustion mixing flower plate 10 is connected to the tar dispersion plate 9 through a fixing plate 11.

[0028] The biomass gas supply pipeline includes a biomass gas inlet duct 5 and a biomass gas duct 6; the biomass gas inlet duct 5 is connected to the biomass gas duct 6 for transporting biomass gas. The primary air duct 1 is provided with the biomass gas duct 6, and the central air duct 3 is arranged in the center of the biomass gas duct 6. An igniter 4 is arranged in the central air duct 3. The primary air duct 1, the central air duct 3, the biomass gas duct 6, the igniter 4, and the air swirler 7 of the entire burner are coaxially arranged.

[0029] The further improvement of the present invention lies in:

[0030] The inclination angle of the swirler blades in the primary air duct is between 30° and 45°, and the inclination angle of the swirler blades in the main combustion gas passage at the front end of the inlet of the biomass gas inlet duct 5 of this burner is between 10° and 20°. It should be noted that the main combustion gas passage does not belong to the present invention and is a front-end component of the present invention. The tar dispersion plate is arranged outside the central air duct, and the dispersion angle is 120°.

[0031] The working principle of the present invention:

[0032] 1. The primary air is sent into the combustion chamber at the rear end of the burner of the present invention through the primary air duct 1. The air swirler 7 located inside the outlet of the primary air duct 1 divides the primary air into direct current air and swirling air. The direct current air can ensure that the fuel ignites and burns in time at the initial stage of combustion, improving the flame stability. The swirling air can enhance the turbulence of the air and strengthen the rapid mixing of the air and the biomass gas. During the post-combustion mixing, a negative pressure area will be formed at the flame center, causing the high-temperature flue gas to flow back and gather. At this time, the central air duct 3 arranged in the center of the biomass gas duct 6 sends part of the pressurized air into the combustion chamber from the flame center, creating an oxygen-rich atmosphere that can ensure the burnout rate of the gas and improve the combustion efficiency of the burner.

[0033] 2. Biomass gas enters the biomass gas pipe 6 through the biomass gas inlet pipe 5. After being accelerated and diverted, it shoots towards the tar dispersion plate 9 set at the outlet of the central air pipe 3. There are two purposes for this. One is to evenly disperse the biomass gas and fully mix it with the air coming out of the air swirler 7 to optimize combustion. The other is to shoot the tar substances carried in the biomass gas at high speed towards the tar dispersion plate 9 to further atomize it fully. Then, together with the pressurized central air ejected from the central air pipe 3, it shoots towards the combustion mixing flower plate 10 in front of the tar dispersion plate 9. The combustion mixing flower plate 10 is evenly arranged with holes to evenly disperse and distribute the mixed gas to assist in full combustion. This dispersed jet technology eliminates the gas aggregation area and avoids the formation of local high-temperature areas, which can effectively reduce the generation of thermal NOx. At the same time, the gas dispersed jet technology speeds up the mixing of gas and air and can effectively inhibit the generation of prompt NOx.

[0034] 3. When the burner is operating, both the tar dispersion plate 9 and the combustion mixing flower plate 10 work in a high-temperature environment. Their adsorbed heat can be instantly transferred to the biomass combustible gas and the tar molecules contained therein, better causing the pyrolysis combustion of the two.

[0035] 4. The biomass gas burner of the present invention fully considers the characteristics of biomass gas, such as generally low calorific value, large density, difficult to ignite by itself, slow flame propagation speed, and high tar content. It reasonably organizes the flow field structure and reasonably controls the mixing of air and biomass gas to ensure that the biomass gas can be completely burned and avoid tar blockage, thereby ensuring the stable and safe operation of the equipment.

[0036] The combined biomass gas burner provided by the present invention is used to solve the problem that the generation amount of nitrogen oxides during the combustion of biomass gas is difficult to meet the requirements of ultra-low nitrogen emissions. The burner includes an air supply pipe, a biomass gas supply pipe, a tar dispersion plate, and a combustion mixing flower plate. Among them, the primary air pipe, the central air pipe, the biomass gas pipe, the igniter, and the air swirler are coaxially arranged. The tar dispersion plate and the combustion mixing flower plate are arranged at the outlet of the biomass gas pipe, and there is a gap between the air swirler and the primary air pipe. Through fuel staged combustion, swirl combustion, and dispersed jet combustion technologies, the mixing of air and biomass gas is reasonably controlled, so that the biomass gas fully reacts with oxygen in the boiler, burns out the tar, improves the combustion efficiency, prevents tar from coking in the burner and the boiler, reduces the cleaning workload, and at the same time reduces the pollution to the environment, achieving the purpose of low NOx combustion of the gas.

[0037] The combined biomass gas burner provided by the present invention solves the problem that the generation amount of nitrogen oxides during the combustion of biomass gas is difficult to meet the requirements of ultra-low nitrogen emissions, causing serious environmental pollution; reasonably controls the mixing of air and biomass gas, enables the biomass gas to fully react with oxygen in the boiler, burns out the tar, improves the combustion efficiency, prevents the tar from coking in the burner and the boiler, reduces the cleaning workload, and at the same time reduces the environmental pollution.

[0038] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A combined biomass gas burner, characterized in that, it includes an air supply pipeline, a biomass gas supply pipeline, an igniter (4), an air swirler (7), a tar dispersion plate (9), and a combustion mixing flower plate (10); the biomass gas supply pipeline and the igniter (4) are coaxially arranged in the air supply pipeline, the air swirler (7) is coaxially arranged at the outer ring outlet of the air supply pipeline, there is a gap between the air swirler (7) and the biomass gas supply pipeline, the tar dispersion plate (9) is arranged at the central outlet of the air supply pipeline, the combustion mixing flower plate (10) is arranged on the tar dispersion plate (9), and holes for uniformly dispersing and distributing the mixed gas and assisting in full combustion are evenly arranged on the combustion mixing flower plate (10), the inclination angle of the blades of the air swirler (7) in the outer ring pipeline of the air supply pipeline is between 30° and 45°, and the dispersion angle of the tar dispersion plate (9) is 110° to 130°.

2. The combined biomass gas burner according to claim 1, characterized in that, the air supply pipeline includes a primary air duct (1), a primary air inlet pipeline (2), and a central air duct (3); the air swirler (7) is installed at the outlet of the primary air duct (1), the primary air inlet pipeline (2) is arranged on the primary air duct (1), the central air duct (3) is coaxially arranged in the primary air duct (1), and the tar dispersion plate (9) is arranged at the outlet of the central air duct (3); the biomass gas supply pipeline includes a biomass gas inlet pipeline (5) and a biomass gas pipe (6); the biomass gas inlet pipeline (5) is connected to the biomass gas pipe (6), and there is a gap between the air swirler (7) and the biomass gas pipe (6); the biomass gas pipe (6) is arranged in the primary air duct (1), the central air duct (3) is arranged in the center of the biomass gas pipe (6), the igniter (4) is arranged in the central air duct (3), and the primary air duct (1), the central air duct (3), the biomass gas pipe (6), the igniter (4), and the air swirler (7) are coaxially arranged; the inclination angle of the blades of the air swirler (7) in the primary air duct (1) is between 30° and 45°.

3. The combined biomass gas burner according to claim 2, characterized in that, the diameter ratio of the primary air duct (1) to the biomass gas pipe (6) is 5:

4.

4. The combined biomass gas burner according to claim 2, characterized in that, there is a gap of 4 - 6 mm between the air swirler (7) and the biomass gas pipe (6).

5. The combined biomass gas burner according to claim 4, characterized in that, there is a gap of 5 mm between the air swirler (7) and the biomass gas pipe (6).

6. The combined biomass gas burner according to claim 1, characterized in that, the dispersion angle of the tar dispersion plate (9) is 120°.

7. The combined biomass gas burner according to claim 1, characterized in that, As described above, a tar dispersion plate (9) is provided at the outlet of the central air duct (3) through a connecting plate (8), and the tar dispersion plate (9) is connected to the combustion mixing flower plate (10) through a fixing plate (11).

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