A swirl burner for co - firing NH3 and pulverized coal

Abstract

The present invention discloses a swirl burner for simultaneously burning NH3 and pulverized coal, which comprises a primary air passage (1), an annular inner secondary air passage (2), an annular NH3 combustion passage (4) and an annular outer secondary air passage (3) arranged in sequence from inside to outside. When the swirl burner operates, NH3 and air burn in the porous medium combustion passage, releasing heat and heating the inner secondary air and the outer secondary air. The excessive NH3 can react with NO in the flue gas in the combustion zone, thereby removing part of the NOx. The present invention can reduce the consumption of coal and can reduce the generation of NOx during the coal combustion process.

Description

Technical Field

[0001] The present invention belongs to the field of combustion technology, and particularly relates to a swirl burner for simultaneously burning NH3 and pulverized coal. Background Art

[0002] In recent years, the world's energy consumption has been increasing continuously. While the consumption of fossil fuels brings social and economic benefits, it will be accompanied by a series of environmental problems. It is required to find other alternative fuels to reduce CO2 emissions. NH3 is regarded as a promising clean energy carrier and storage medium. NH3 can be obtained from biomass or other renewable resources, with a relatively low unit storage energy cost, a relatively high volume energy density, and good safety and reliability. Therefore, using NH3 to replace part of the coal combustion can reduce CO2 emissions. At the same time, NH3 can be synthesized by electric energy. By burning NH3, new energy electricity can be stored, and NH3 can be used as an energy storage material with low price and easy access. Summary of the Invention

[0003] The purpose of the present invention is to provide a swirl burner for simultaneously burning NH3 and pulverized coal, which can simultaneously burn NH3 and pulverized coal. During the combustion process of NH3, heat is released to heat the air required for the combustion of pulverized coal. After the excessive NH3 enters the combustion zone of the boiler furnace, it can reduce NOx in the flue gas, thereby reducing the generation of NOx during the boiler combustion process. By burning NH3, the coal consumption required for the boiler to carry the load is reduced.

[0004] The present invention has the advantage of being able to simultaneously burn NH3 and pulverized coal. It can use the combustion of NH3 to replace part of the pulverized coal, thereby reducing coal consumption and reducing the generation of NOx during the combustion process.

[0005] The present invention is implemented by the following technical solutions:

[0006] A swirl burner for simultaneously burning NH3 and pulverized coal, comprising a primary air passage, an annular inner secondary air passage, an annular NH3 combustion passage, and an annular outer secondary air passage arranged in sequence from the inside to the outside.

[0007] A further improvement of the present invention is that the primary air carries pulverized coal and enters the primary air passage through the primary air inlet, and the flow rate of the primary air and pulverized coal is controlled by a primary air valve.

[0008] A further improvement of the present invention is that the inner secondary air enters the annular inner secondary air passage through the inner secondary air inlet, and the flow rate of the inner secondary air is controlled by an inner secondary air valve.

[0009] A further improvement of the present invention is that the outer secondary air enters the annular outer secondary air passage through the outer secondary air inlet, and the flow rate of the outer secondary air is controlled by an outer secondary air valve.

[0010] A further improvement of the present invention is that NH3 and air enter the annular NH3 combustion channel through the NH3 inlet, and the flow rates of NH3 and air are controlled by the NH3 valve and the air control valve respectively.

[0011] A further improvement of the present invention is that the annular NH3 combustion channel includes a premixing chamber at the front end and a porous medium combustion zone at the rear end.

[0012] A further improvement of the present invention is that the porous medium combustion zone uses a metal porous medium with good heat transfer characteristics.

[0013] A further improvement of the present invention is that the flow rates of NH3 and air are controlled by the NH3 valve and the air control valve, and after entering the premixing chamber through the NH3 inlet for sufficient premixing, premixed combustion occurs in the porous medium combustion zone. Heat is released during the combustion process, and the heat is used to heat the inner secondary air in the annular inner secondary air channel and the outer secondary air in the outer secondary air channel.

[0014] A further improvement of the present invention is that the ratio of NH3 to air controlled by the NH3 valve and the air control valve is 1:2.975 to 1:3.571.

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

[0016] (1) The burner of the present invention can burn part of NH3 and release heat to replace coal. Since no CO2 is generated after the combustion of NH3, the use of the burner of the present invention can help reduce CO2 emissions.

[0017] (2) During the combustion of gaseous NH3 in the annular NH3 combustion channel distributed between the inner secondary air channel and the outer secondary air channel, heat is released, and the heat is transferred to the inner secondary air in the inner secondary air channel and the outer secondary air in the outer secondary air channel through heat conduction, increasing the temperature of the inner secondary air and the outer secondary air, which can improve the stability of pulverized coal ignition and promote the ignition and burnout of pulverized coal. Therefore, the burner of the present invention is particularly suitable for difficult-to-combust coal types with low volatile content and high ignition point.

[0018] (3) In the burner of the present invention, during the combustion of NH3 and air, NH3 is in a slightly excessive state. After the unburned NH3 enters the pulverized coal combustion area, it will react with NO in the flue gas to generate N2 and H2O, thereby removing part of the NOx in the flue gas and achieving the purpose of reducing NOx emissions. Description of the Drawings

[0019] Figure 1 It is the front view of the swirl burner of the present invention.

[0020] Figure 2 It is the top view of the swirl burner of the present invention.

[0021] Description of Reference Numerals:

[0022] 1 - Primary air passage; 2 - Annular inner secondary air passage; 3 - Annular outer secondary air passage; 4 - Annular NH3 combustion passage; 5 - Premixing chamber; 6 - Porous medium combustion zone; 7 - Primary air valve; 8 - Inner secondary air valve; 9 - Outer secondary air valve; 10 - NH3 valve; 11 - Air control valve. Detailed Embodiments

[0023] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be completely conveyed to those skilled in the art. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0024] As Figure 1 and Figure 2 shown, a swirl burner for simultaneously burning NH3 and pulverized coal provided by the present invention includes a circular primary air passage 1, an annular inner secondary air passage 2 outside the primary air passage 1, an annular NH3 combustion passage 4 outside the annular inner secondary air passage 2, and an annular outer secondary air passage 3 outside the annular NH3 combustion passage 4.

[0025] Preferably, the primary air carrying pulverized coal enters the primary air passage 1 through the primary air inlet 12, and the flow rates of the primary air and the pulverized coal are controlled by the primary air valve 7.

[0026] Preferably, the inner secondary air enters the annular inner secondary air passage 2 through the inner secondary air inlet 13, and the flow rate of the inner secondary air is controlled by the inner secondary air valve 8.

[0027] Preferably, the outer secondary air enters the annular outer secondary air passage 3 through the outer secondary air inlet 14, and the flow rate of the outer secondary air can be controlled by the outer secondary air valve 9.

[0028] Preferably, NH3 and air enter the annular NH3 combustion passage 4 through the NH3 inlet 15, and the flow rates of NH3 and air are respectively controlled by the NH3 valve 10 and the air control valve 11.

[0029] Preferably, the annular NH3 combustion passage 4 includes a premixing chamber 5 at the front end and a porous medium combustion zone 6 at the rear end

[0030] Preferably, the porous medium combustion zone 6 uses a metal porous medium with good heat transfer characteristics.

[0031] Preferably, the flow rates of NH3 and air are controlled by the NH3 valve 10 and the air control valve 11, and after entering the premixing chamber 5 through the NH3 inlet 15 for sufficient premixing, premixed combustion is carried out in the porous medium combustion zone 6. The combustion process releases heat, and the heat is used to heat the inner secondary air in the annular inner secondary air channel 2 and the outer secondary air in the outer secondary air channel 3.

[0032] Preferably, the NH3 valve 10 and the air control valve 11 control the ratio of NH3 to air to be 1:2.975 to 1:3.571.

[0033] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made thereto based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A swirl burner for simultaneously burning NH3 and pulverized coal, characterized in that, It includes a primary air passage (1), an annular inner secondary air passage (2), an annular NH3 combustion passage (4), and an annular outer secondary air passage (3) arranged successively from the inside to the outside; NH3 and air enter the annular NH3 combustion passage (4) through the NH3 inlet (15), and the flow rates of NH3 and air are controlled by the NH3 valve (10) and the air control valve (11) respectively; the annular NH3 combustion passage (4) includes a premixing chamber (5) at the front end and a porous medium combustion zone (6) at the rear end; the porous medium combustion zone (6) uses a metal porous medium with good heat transfer characteristics; the ratio of NH3 to air controlled by the NH3 valve (10) and the air control valve (11) is 1:2.975 to 1:3.571; The primary air carries pulverized coal and enters the primary air passage (1) through the primary air inlet (12), and the flow rate of the primary air and the pulverized coal is controlled by the primary air valve (7).

2. A swirl burner for simultaneously burning NH3 and pulverized coal according to claim 1, characterized in that, The inner secondary air enters the annular inner secondary air passage (2) through the inner secondary air inlet (13), and the flow rate of the inner secondary air is controlled by the inner secondary air valve (8).

3. A swirl burner for simultaneously burning NH3 and pulverized coal according to claim 1, characterized in that, The outer secondary air enters the annular outer secondary air passage (3) through the outer secondary air inlet (14), and the flow rate of the outer secondary air is controlled by the outer secondary air valve (9).

4. A swirl burner for simultaneously burning NH3 and pulverized coal according to claim 1, characterized in that, NH3 and air are controlled in flow rate by the NH3 valve (10) and the air control valve (11), enter the premixing chamber (5) through the NH3 inlet (15) for sufficient premixing, and then undergo premixed combustion in the porous medium combustion zone (6). Heat is released during the combustion process, and the heat is used to heat the inner secondary air in the annular inner secondary air passage (2) and the outer secondary air in the annular outer secondary air passage (3).

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