Gas Burner

Abstract

The present invention provides a gas burner, comprising: a combustion chamber, which is a cylindrical structure with two ends open, and the combustion chamber has an inner cavity; an annular flow sleeve, which is a stepped structure and is located in the inner cavity, the large diameter section of the annular flow sleeve abuts against the inner wall of the first end of the combustion chamber, and a plurality of premixing chambers for connecting input air are arranged on the large diameter section, the first end of the small diameter section is connected to the large diameter section, the second end of the small diameter section is open and opposite to the second end of the combustion chamber, an annular space is arranged between the small diameter section and the inner wall of the combustion chamber, the premixing chamber is connected to the annular space, and a flue gas port group is arranged on the outer periphery of the small diameter section; a plurality of first-stage gas spray guns, each premixing chamber is correspondingly penetrated with a first-stage gas spray gun; a second-stage gas spray gun is axially penetrated in the annular flow sleeve, and the outlet end of the second-stage gas spray gun is placed outside the annular flow sleeve and faces the second end of the combustion chamber. This embodiment retains the original characteristics of high-speed combustion, which is to enhance convection heating, and at the same time has a low-nitrogen combustion effect.

Description

Technical Field

[0001] The invention relates to the field of industrial heating and heat treatment, and in particular to a gas burner. Background Art

[0002] High-speed burners have the characteristics of compact structure, high convection heat transfer coefficient, good automation, etc., and are widely used in various heat treatment furnaces and heating furnaces. As the current increasingly serious atmospheric environmental pollution problem forces all parts of the country to implement more stringent ultra-low pollutant emission standards, achieving clean low-nitrogen combustion in industrial heating and heat treatment equipment is of great significance for green and sustainable development.

[0003] Traditional high-speed burners focus on fully mixing fuel and air in the combustion chamber to obtain high-intensity combustion in a compact combustion volume, thereby achieving high-speed jet air velocity and ensuring the convection heat transfer coefficient in the furnace to meet the needs of many processes. However, traditional high-speed burners are difficult to meet the increasingly stringent ultra-low emission requirements of current emission standards.

[0004] In recent years, there have been many high-speed burners that use various types of staged combustion technologies to achieve low pollution emissions. However, the essence of these so-called high-speed burners is to allow part of the fuel to enter the furnace before burning, thereby reducing the combustion intensity in the combustion chamber. Although this can achieve the effect of low-nitrogen combustion, it sacrifices the airflow ejection speed of high-speed combustion, affects the convective heat transfer effect, and is not conducive to uniform heating and energy saving. Summary of the invention

[0005] The present invention provides a gas burner to achieve the purpose of reducing the generation of pollutants while ensuring the ejection speed.

[0006] The technical solution adopted by the present invention to solve its technical problems is: a gas burner, comprising: a combustion chamber, which is a cylindrical structure with openings at both ends, and the combustion chamber has an inner cavity; a circulating sleeve, which is a stepped structure and is located in the inner cavity, the large-diameter section of the circulating sleeve abuts against the inner wall of the first end of the combustion chamber, and a plurality of premixing chambers for connecting input air are arranged on the large-diameter section, the first end of the small-diameter section is connected to the large-diameter section, the second end of the small-diameter section is open and opposite to the second end of the combustion chamber, an annular space is provided between the small-diameter section and the inner wall of the combustion chamber, the premixing chamber is connected to the annular space, and a flue gas port group is arranged on the outer periphery of the small-diameter section; a plurality of primary gas spray guns, each premixing chamber correspondingly penetrated with a primary gas spray gun; a secondary gas spray gun, which is axially penetrated in the circulating sleeve, and the outlet end of the secondary gas spray gun is placed outside the circulating sleeve and faces the second end of the combustion chamber.

[0007] Furthermore, the plurality of premixing chambers are evenly spaced along the circumference of the large diameter section.

[0008] Furthermore, there are multiple smoke outlet groups, and the multiple smoke outlet groups correspond one-to-one to the positions of the multiple premixing chambers.

[0009] Furthermore, each smoke inlet group includes a main smoke flow hole and a secondary smoke flow hole, which are arranged at intervals along the axial direction of the circulation sleeve, and the aperture of the main smoke flow hole is larger than that of the secondary smoke flow hole.

[0010] Furthermore, the main smoke guide hole is located at the first end of the small diameter section, and there are multiple secondary smoke guide holes, which are evenly spaced between the main smoke guide hole and the second end of the small diameter section.

[0011] Furthermore, the diameter of the first section opening of the combustion chamber is larger than the diameter of the second end opening of the combustion chamber, and an arc-shaped guide structure is provided at the connection between the second end opening of the combustion chamber and the inner cavity wall.

[0012] Furthermore, the nozzle flow rate of the first-stage gas spray gun is 40m / s to 200m / s, and the proportion of primary gas at the first-stage gas spray gun is 50 to 90%.

[0013] Furthermore, the nozzle flow rate of the secondary gas spray gun is 60m / s to 150m / s, and the proportion of secondary gas at the secondary gas spray gun is 10 to 50%.

[0014] Furthermore, the gas burner also includes an air pipeline connected to the multiple premixing chambers.

[0015] Furthermore, the gas burner also includes a gas pipeline connected to the secondary gas spray gun and multiple primary gas spray guns.

[0016] The beneficial effect of the present invention is that high-speed flue gas is formed by combustion at the first-stage gas spray gun. After entering the annular space of the combustion chamber, a circulation effect is formed around the circulation sleeve under the guidance of the circulation sleeve, thereby reducing the peak temperature of the primary combustion and inhibiting nitrogen oxides. Under the reduction effect of the gas sprayed from the second-stage gas spray gun, the flue gas is completely burned and sprayed from the second end of the combustion chamber, forming an ultra-low emission high-speed spray airflow. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 is a structural diagram of an embodiment of the present invention;

[0019] Figure 2 It is the layout diagram of the first-stage gas spray gun of the present invention;

[0020] Figure 3It is a structural diagram of the annular flow sleeve of the present invention.

[0021] Reference numerals in the figure: 1. air pipeline; 2. gas pipeline; 3. primary gas spray gun; 4. premixing chamber; 5. secondary gas spray gun; 6. combustion chamber; 7. flue gas outlet; 8. circulating sleeve; 9. main flue gas guide hole; 10. secondary flue gas guide hole. DETAILED DESCRIPTION

[0022] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0023] like Figures 1 to 3 As shown, an embodiment of the present invention provides a gas burner, including a combustion chamber 6, an annular sleeve 8, a plurality of primary gas spray guns 3 and a secondary gas spray gun 5. The combustion chamber 6 is a cylindrical structure with two ends open, and the combustion chamber 6 has an inner cavity. The annular sleeve 8 is a stepped structure and is located in the inner cavity. The large diameter section of the annular sleeve 8 abuts against the inner wall of the first end of the combustion chamber 6. The large diameter section is provided with a plurality of premixing chambers 4 for connecting the input air. The first end of the small diameter section is connected to the large diameter section. The second end of the small diameter section is open and opposite to the second end of the combustion chamber 6. There is an annular space between the small diameter section and the inner wall of the combustion chamber 6. The premixing chamber 4 is connected to the annular space, and a flue gas port group is provided on the outer periphery of the small diameter section. A primary gas spray gun 3 is correspondingly penetrated in each premixing chamber 4. The secondary gas spray gun 5 is axially penetrated in the annular sleeve 8, and the outlet end of the secondary gas spray gun 5 is placed outside the annular sleeve 8 and faces the second end of the combustion chamber 6.

[0024] The high-speed flue gas is burned at the primary gas spray gun 3. After entering the annular space of the combustion chamber 6, it forms a circulation effect around the circulation sleeve 8 under the guidance of the circulation sleeve 8, thereby reducing the primary combustion temperature peak and suppressing nitrogen oxides. Under the reduction effect of the gas sprayed from the secondary gas spray gun 5, it is completely burned and sprayed from the second end of the combustion chamber 6, forming an ultra-low emission high-speed spray airflow (nitrogen oxides are less than 150mg / m 3 ).

[0025] The primary combustion at the first-stage gas spray gun 3 uses a premix of gas and excess air. Since the primary gas is in a premixed lean combustion state, it can ensure stable flame combustion while being diluted by excess air. The peak temperature of the combustion flame is low, avoiding the large-scale generation of high-temperature thermal nitrogen oxides in the primary combustion.

[0026] The number of the first-stage gas spray guns 3 can be increased as needed, and they are distributed in a circular array along the circumference. The outlets of the first-stage gas spray guns 3 are all placed in the annular space, that is, the combustion area is located in the annular space formed by the inner surface of the combustion chamber 6 and the outer side of the annular sleeve 8, and the positions of the multiple premixing chambers 4 correspond to the positions of the first-stage gas spray guns 3. After the high-temperature flue gas generated by the primary combustion flows out of the annular space, a part of the flue gas flows back from the inner side of the annular sleeve 8 due to the effect of the induced negative pressure, and flows back into the annular space at the position of the flue gas port group, thereby further diluting the oxygen concentration and gas concentration in the combustion area, reducing the intensity of the combustion reaction, and further reducing the generation of nitrogen oxides.

[0027] Another part of the flue gas is ejected at high speed from the second end opening of the combustion chamber 6 (the flue gas outlet 7) and enters the furnace space, while part of the fuel gas ejected from the secondary gas spray gun 5 can continue to burn before the high-temperature flue gas is ejected. At this time, the oxygen concentration in the high-temperature flue gas is greatly reduced, so the combustion reaction is relatively mild, and a large amount of pollutants can also be avoided. At the same time, the intermediate products such as CO and H2 produced by this part of the fuel reaction can also reduce the nitrogen oxides produced in the combustion chamber, thereby further reducing the pollutants produced in the combustion chamber.

[0028] It should be noted that the nozzle shape of the primary gas spray gun 3 can be circular or non-axisymmetric special-shaped nozzle. The nozzle shape of the secondary gas spray gun 5 can be circular or non-axisymmetric special-shaped nozzle, and the number of nozzle openings of the secondary gas spray gun 5 can be one or more combinations.

[0029] Specifically, there are multiple smoke outlet groups, and the multiple smoke outlet groups correspond one to one with the positions of the multiple premixing chambers 4. The correspondence between the smoke outlet groups and the premixing chambers 4 can allow the smoke to flow back into the annular space, thereby further diluting the oxygen concentration and fuel gas concentration in the combustion area, reducing the intensity of the combustion reaction, and further reducing the generation of nitrogen oxides.

[0030] like Figure 1 and Figure 3 As shown, in the embodiment of the present invention, each smoke outlet group includes a main smoke flow hole 9 and a secondary smoke flow hole 10, and the main smoke flow hole 9 and the secondary smoke flow hole 10 are arranged at intervals along the axial direction of the annular sleeve 8, and the aperture of the main smoke flow hole 9 is larger than that of the secondary smoke flow hole 10. The main smoke flow hole 9 and the secondary smoke flow hole 10 are arranged to increase the smoothness of smoke reflux and prevent smoke from being ejected from the outlet due to slow reflux.

[0031] Preferably, the main smoke flow hole 9 is located at the first end of the small diameter section, and there are multiple secondary smoke flow holes 10, which are evenly spaced between the main smoke flow hole 9 and the second end of the small diameter section. The main smoke flow hole 9 is set at the first end of the small diameter section so that most of the smoke starts to dilute the oxygen concentration and gas concentration in the combustion area at the starting position of the annular space, thereby reducing the intensity of the combustion reaction. The main smoke flow hole 9 and the secondary smoke flow hole 10 can be circular, rectangular or other shapes.

[0032] like Figure 1 As shown, the diameter of the first section opening of the combustion chamber 6 is larger than the diameter of the second end opening of the combustion chamber 6, and an arc-shaped guide structure is provided at the connection between the second end opening of the combustion chamber 6 and the inner cavity wall. The arc-shaped guide structure is provided to correspond to the position of the annular space, and can guide the smoke ejected at high speed from the annular space to facilitate the smoke reflux.

[0033] The nozzle velocity of the primary gas spray gun 3 is 40m / s-200m / s, and the primary gas ratio at the primary gas spray gun 3 is 50-90%. The nozzle velocity of the secondary gas spray gun 5 is 60m / s-150m / s, and the secondary gas ratio at the secondary gas spray gun 5 is 10-50%.

[0034] The gas burner further comprises an air pipeline 1 connected to the plurality of premixing chambers 4. The gas burner further comprises a gas pipeline 2 connected to the secondary gas spray gun 5 and the plurality of primary gas spray guns 3.

[0035] In the embodiment of the present invention, the air pipeline 1 and the gas pipeline 2 are provided to respectively provide air and gas to the combustion chamber, and the amount of air and gas can be controlled separately, so as to facilitate the adjustment of the gas ratio.

[0036] From the above description, it can be seen that the above-mentioned embodiments of the present invention achieve the following technical effects: the present invention not only retains the original characteristics of high-speed combustion by blowing and enhancing convection heating, but also has the effect of low-nitrogen combustion, realizes high-intensity and low-pollution combustion in a compact combustion space, and adapts to the low-pollution emission requirements of various heat treatment furnaces and heating furnaces that rely on convection heat exchange.

[0037] The above is only a specific embodiment of the present invention, and cannot be used to limit the scope of the invention. Therefore, the replacement of equivalent components, or equivalent changes and modifications made according to the scope of protection of the patent of the present invention, should still fall within the scope of this patent. In addition, the technical features of the present invention can be freely combined with each other, with each other, and with each other.

Claims

1. A gas burner, characterized in that: include: The combustion chamber (6) is a cylindrical structure with openings at both ends, and the combustion chamber (6) has an inner cavity; A circulation sleeve (8) having a stepped structure and being located in the inner cavity, wherein a large diameter section of the circulation sleeve (8) abuts against an inner wall of a first end of the combustion chamber (6), a plurality of premixing chambers (4) for connecting input air are arranged on the large diameter section, a first end of a small diameter section of the circulation sleeve (8) is connected to the large diameter section, a second end of the small diameter section is open and opposite to the second end of the combustion chamber (6), an annular space is provided between the small diameter section and the inner wall of the combustion chamber (6), the premixing chamber (4) is in communication with the annular space, and a flue gas outlet group is arranged on the outer periphery of the small diameter section; A plurality of first-stage gas spray guns (3), each of the premixing chambers (4) being provided with a corresponding first-stage gas spray gun (3); A secondary gas spray gun (5) is axially inserted into the circulation sleeve (8), and an outlet end of the secondary gas spray gun (5) is located outside the circulation sleeve (8) and faces the second end of the combustion chamber (6); The diameter of the first section opening of the combustion chamber (6) is larger than the diameter of the second end opening of the combustion chamber (6), and an arc-shaped guide structure is provided at the connection between the second end opening of the combustion chamber (6) and the inner cavity wall; The plurality of premixing chambers (4) are evenly spaced along the circumference of the large diameter section.

2. The gas burner according to claim 1, characterized in that: There are a plurality of smoke outlet groups, and the positions of the plurality of smoke outlet groups correspond one-to-one to the positions of the plurality of premixing chambers (4).

3. The gas burner according to claim 2, characterized in that: Each of the smoke inlet groups comprises a main smoke flow hole (9) and a secondary smoke flow hole (10); the main smoke flow hole (9) and the secondary smoke flow hole (10) are arranged at intervals along the axial direction of the circulation sleeve (8); the aperture of the main smoke flow hole (9) is larger than that of the secondary smoke flow hole (10).

4. The gas burner according to claim 3, characterized in that: The main smoke guide hole (9) is located at the first end of the small diameter section, and the secondary smoke guide holes (10) are multiple, and the multiple secondary smoke guide holes (10) are evenly spaced between the main smoke guide hole (9) and the second end of the small diameter section.

5. The gas burner according to claim 1, characterized in that: The nozzle flow rate of the first-stage gas spray gun (3) is 40m / s to 200m / s, and the primary gas ratio at the first-stage gas spray gun (3) is 50% to 90%.

6. The gas burner according to claim 1, characterized in that: The nozzle flow rate of the secondary gas spray gun (5) is 60m / s to 150m / s, and the proportion of secondary gas at the secondary gas spray gun (5) is 10 to 50%.

7. The gas burner according to claim 1, characterized in that: The gas burner also includes an air pipeline (1) connected to each of the plurality of premixing chambers (4).

8. The gas burner according to claim 1, characterized in that: The gas burner further comprises a gas pipeline (2) connected to both the secondary gas spray gun (5) and the plurality of primary gas spray guns (3).

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