An ultra-low nitrogen burner head for a horizontally installed vertical combustion burner

Abstract

The present invention discloses an ultra-low nitrogen burner head for a horizontally installed vertical combustion burner, which comprises a burner head assembly, a porous ceramic column and a combined swirl cap. The burner head assembly is composed of an installation flange, an inner air cylinder, a front end plate, an upper plate, a lower plate and a rear end plate assembly. The front end of the inner air cylinder is connected to the installation flange and inserted into the burner head shell through a through hole opened on the front end plate, and is connected to the front end plate. By designing the present invention, partial flue gas reflux will be formed at the outlet of each independent combined swirl cap. The partial high-temperature flue gas reflux is beneficial to the formation of a rotating and stable flame shape. The combustion products participate in the combustion, further reducing pollutant emissions. In addition, its multi-cluster flame shape reduces the high-temperature area, and the overall divergent combustion has a large heat dissipation area and fast heat dissipation, effectively reducing the generation of thermal NOx.

Description

Technical Field

[0001] The present invention relates to the technical field of gas burners, and particularly relates to an ultra-low nitrogen combustion head for a horizontally installed vertical combustion burner. Background Art

[0002] With the increasing prominence of environmental problems, the formulation of relevant gas fuel combustion appliance standards at home and abroad, and the implementation of nitrogen oxide control measures by government environmental protection departments, more and more low-nitrogen combustion technologies have been applied to the combustion technology field. It is recognized at home and abroad in the combustion field that a burner with a combustion product NO X content lower than 30 mg / m³ is called an ultra-low nitrogen burner.

[0003] There are mainly three forms of nitrogen oxide generation during the combustion process, namely thermal NO X , prompt NO X , and fuel NO X . During the combustion process of a natural gas burner mainly composed of methane, thermal NO X is the main form.

[0004] At present, the nitrogen reduction technical measures of ultra-low nitrogen burners on the market mainly adopt flue gas recirculation technology and full premix combustion technology. The combustion head applying flue gas recirculation technology has a complex structure and a large size, and is mainly applied to large gas boilers. While small gas heating furnaces mainly adopt full premix combustion technology. Full premix combustion means that before the combustion of the burner, the gas and all the required air are fully mixed, and then rapid and complete combustion occurs after the fire holes. The NO X reduction technology of full premix combustion is to make the excess air coefficient in the combustion area much greater than 1, so that it burns in an oxygen-rich state. In this way, both the combustion efficiency can be guaranteed, and the combustion temperature can be effectively suppressed, thereby achieving the purpose of controlling the NO X generation amount.

[0005] At present, for vertical heating furnaces with a heat load below 1 MW on the market, some are equipped with simple partial premix gas burners, and some are equipped with forced draft full premix burners. For the former, due to the structural dimensions of the heating furnace and the fact that most of the simple partial premix burners are ejector structures, the primary air supply is insufficient, the secondary air supply is uneven, the flame is long, the flue gas flow rate is fast, and the residence time in the furnace is short, so the NO X generation amount is relatively large, mostly above 100 mg / m³. For the latter, at present, most full premix burners at home and abroad are flat plate type and cylindrical type. Whether it is a flat plate type or a cylindrical type combustion head, the surface is mostly made of metal fiber materials or porous ceramic plate materials, and usually adopts a continuous sheet structure form. This structure form has several disadvantages: one is that the flames are closely connected during the combustion process, and there is a large area of high-temperature region inside; the other is that there is almost no flue gas circulation participating in the combustion in the combustion area to reduce the flame temperature. These two main reasons result in the NO emittedX The content is difficult to be lower than 30mg / m³. Therefore, their applications in heating equipment with a small combustion space and under conditions with ultra-low nitrogen requirements are somewhat limited. Summary of the Invention

[0006] The purpose of the present invention is to provide an ultra-low nitrogen combustion head for a horizontally installed vertical combustion burner that uses natural gas as fuel and applies the full premixed combustion method to solve the technical problems existing in premixed burners.

[0007] To achieve the above purpose, the technical solution adopted by the present invention is as follows.

[0008] An ultra-low nitrogen combustion head for a horizontally installed vertical combustion burner includes a combustion head assembly, a porous ceramic column, and a combined swirl cap. The combustion head assembly is composed of an installation flange, an inner air cylinder, a front end plate, an upper plate, a lower plate, and a rear end plate combination. The front end of the inner air cylinder is connected to the installation flange and inserted into the combustion head housing through a through hole opened on the front end plate, and is connected to the front end plate.

[0009] Furthermore, the upper plate of the combustion head assembly is composed of two surfaces with an included angle. Multiple through holes are evenly distributed on the upper plate surface and at the top of the included angle. Multiple sleeves are provided at corresponding positions, and porous ceramic columns are placed in the sleeves. The combined swirl cap is arranged on each sleeve.

[0010] Furthermore, a plurality of ventilation holes are arranged from the front end to the rear end of the inner air cylinder. The ventilation holes are densely arranged on the surface of the inner air cylinder. The aperture of the ventilation holes gradually decreases along the axis in the direction from the front end plate to the rear end plate. The total opening area of the plurality of ventilation holes is equal to the inlet area of the installation flange.

[0011] Furthermore, the diameter of the ceramic column is between 20 and 40mm, and the height is between 20 and 40mm. Preferably, the diameter of its small holes is between 2 and 3mm.

[0012] Furthermore, the combined swirl cap includes a flame stabilization disk, a swirl vane, and a swirl member housing. The flame stabilization disk has through holes. The swirl vane is arranged between the flame stabilization disk and the swirl member housing. The swirl vane forms a certain angle with the axial gas outlet direction of the combined swirl cap. There are 4 to 16 swirl vanes, and each swirl vane is evenly distributed in a ring outside the flame stabilization disk. The flame stabilization disk is arranged inside the swirl member housing, 5 to 10mm lower than the outer edge of the swirl member housing, and the swirl vane is 5 to 10mm lower than the outer plane of the flame stabilization disk.

[0013] Furthermore, the sleeve is provided with a thread that can be connected to the combined swirl cap. The lower surface of the sleeve is a bevel structure, and when it is arranged together with the upper plate, it forms a certain angle with the contact surface.

[0014] Furthermore, one or more sewage discharge holes are provided on the rear end plate.

[0015] As can be seen from the above technical solutions, the embodiments of the present invention have the following advantages:

[0016] The burner head of the present invention has a compact structure and obvious advantages: First, partial flue gas recirculation will form at the outlet of each independent combined swirl cap. The recirculation of partial high-temperature flue gas is beneficial to the formation of a rotating and stable flame shape, and the combustion products participating in the combustion further reduce pollutant emissions; Second, its multi-cluster flame shape reduces the high-temperature area, has a large overall divergent combustion heat dissipation area, fast heat dissipation, and effectively reduces the generation of thermal NOx.

[0017] The burner head of the present invention can be designed with burner heads of different heat loads according to user needs. The lengths of the upper plate and the lower plate of the burner head can be adjusted, and the corresponding number of sleeves, porous ceramic columns, and combined swirl caps can be configured, with other components remaining unchanged.

[0018] One or more sewage discharge holes are provided on the rear end plate of the burner head of the present invention. When using associated gas from oil fields, oil-water or impurities can be discharged, enabling the burner to operate continuously and stably, and reducing the impact of shutdown on production.

[0019] As can be seen from the above, the burner head of the present invention applies various NOx reduction technical measures such as multi-cluster internal flue gas circulation, oxygen-enriched combustion, and multi-cluster flames to reduce flame temperature, suppress the generation of NOx from the combustion mechanism, effectively reduce NOx emissions, has a stable flame shape, is applicable to self-produced gas from oil fields, and has a wide range of applications. The burner head of the present invention can be used not only in small and medium-sized industrial vertical heating furnaces, but also in civil or commercial heating or hot water furnaces. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments and the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0021] Figure 1 It is a three-dimensional structure schematic diagram of the present invention.

[0022] Figure 2 It is a semi-sectional structure schematic diagram of the burner head assembly of the present invention.

[0023] Figure 3 It is a front view structure schematic diagram of the present invention.

[0024] Figure 4 For the Figure 3 A-A sectional structure schematic diagram of this.

[0025] Figure 5 It is a schematic diagram of the decomposition of the combined swirl cap.

[0026] Figure 6 It is a schematic diagram of the partial flue gas internal circulation flow trajectory line and partial gas swirl trajectory line during the combustion process of a single combined swirl cap.

[0027] In the figure, 1 is the combustion head assembly; 2 is the porous ceramic column; 3 is the combined swirl cap; 11 is the mounting flange; 12 is the inner air duct; 13 is the front end plate; 14 is the upper plate; 15 is the lower plate; 16 is the rear end plate; 17 is the sleeve; 121 is the ventilation hole; 141 is the through hole; 31 is the flame stabilizing disc; 32 is the swirl vane; 33 is the outer shell of the swirl component. Specific implementation mode

[0028] This embodiment is the preferred implementation mode of the present invention. All other embodiments with the same or similar principles and basic structures as this embodiment are within the protection scope of the present invention.

[0029] Please refer to the appendix Figure 1 to appendix Figure 6 The present invention is an ultra-low nitrogen combustion head for a horizontally installed vertical combustion burner, including a combustion head assembly 1, a porous ceramic column 2 and a combined swirl cap 3. The combustion head assembly 1 is composed of a mounting flange 11, an inner air duct 12, a front end plate 13, an upper plate 14, a lower plate 15 and a rear end plate 16. The front end of the inner air duct 12 is connected to the mounting flange 11 and inserted into the combustion head housing 1 through the through hole opened on the front end plate 13, and is connected to the front end plate 13.

[0030] In this embodiment, the upper plate 14 of the combustion head assembly 1 includes two top surfaces forming an angle. A plurality of sleeves 17 are arranged on the upper plate 14 surface and at the top of the angle. Through holes 141 are opened at the corresponding positions of the sleeves 17 for the mixed gas to flow through. Porous ceramic columns 2 are placed in the sleeves 17. The combined swirl cap 3 is arranged on each sleeve 17. The lengths of the upper plate 14 and the lower plate 15, and the numbers of the sleeves 17, the porous ceramic columns 2 and the combined swirl caps 3 are adjusted according to the heat load requirements.

[0031] In this embodiment, a plurality of ventilation holes 121 are arranged from the front end to the rear end of the inner air duct 12. The ventilation holes 121 are densely arranged on the surface of the inner air duct 12. The aperture of the ventilation holes 121 gradually decreases in the direction from the front end plate 13 to the rear end plate 16 along the axis. The total opening area of the plurality of ventilation holes 121 is equivalent to the inlet area of the mounting flange 11. The length of the inner air duct 12 is adjusted according to the heat load requirements.

[0032] In this embodiment, a plurality of small holes are evenly distributed on the porous ceramic column 2. The diameter of the ceramic column 2 is between 20 and 40 mm, and the height is between 20 and 40 mm, so that the diameter of the small holes is between 2 and 3 mm, enabling the mixed gas to flow out evenly. The porous ceramic material is used to minimize the heat transfer from the combustion surface to the inside of the burner head.

[0033] In this embodiment, the combined swirl cap 3 includes a flame stabilizing disc 31, a swirl vane 32, and a swirl member housing 33. The flame stabilizing disc 31 is provided with through holes, and the shapes of the through holes are round holes, square holes, long strip holes, polygon holes, or star-shaped holes; the swirl vane 32 is disposed between the flame stabilizing disc 31 and the swirl member housing 33. The swirl vane 32 forms a certain angle with the axial gas outlet direction of the combined swirl cap 3, preferably 45°, and optionally 30 to 75°. The swirl vane 32 is provided with 4 to 16 pieces, preferably 12 pieces. Each swirl vane 32 is evenly distributed in a ring outside the flame stabilizing disc 31. The flame stabilizing disc 31 is disposed inside the swirl member housing 33, 5 to 10 mm lower than the outer edge of the swirl member housing 33, and the swirl vane 32 is 5 to 10 mm lower than the outer plane of the flame stabilizing disc 31. When the burner operates, partial flue gas recirculation will be formed at the outlet of each independent combined swirl cap 3. The partial high-temperature flue gas recirculation is beneficial to the formation of a rotating and stable flame shape. The combustion products participate in combustion, further reducing pollutant emissions.

[0034] In this embodiment, the sleeve 17 is provided with threads that can be connected to the combined swirl cap 3. The lower surface of the sleeve 17 is a bevel structure. When it is arranged together with the upper plate 14, it forms a certain angle with the contact surface, optionally between 20 and 75°, preferably between 45 and 60°. Different angles can be set for heating furnaces with different diameters to adjust the area of flame divergence. The multi-cluster flame shape reduces the high-temperature area. The overall divergent combustion has a large heat dissipation area and fast heat dissipation, effectively reducing the generation of thermal NOx.

[0035] In this embodiment, the rear end plate 16 is provided with one or more blowdown holes, and the aperture is optionally between 2 and 5 mm, preferably between 3 and 4 mm. When using associated gas in oil fields, oil, water, or impurities can be discharged.

[0036] The first advantage of the present invention is that partial flue gas recirculation will be formed at the outlet of each independent combined swirl cap. The partial high-temperature flue gas recirculation is beneficial to the formation of a rotating and stable flame shape. Part of the flue gas circulates and participates in combustion, reducing the flame temperature, and thus reducing pollutant emissions; the second is that its multi-cluster flame shape reduces the high-temperature area. The overall divergent combustion has a large heat dissipation area and fast heat dissipation, further reducing the generation of thermal NOx.

Claims

1. An ultra-low nitrogen burner head for a horizontally installed vertical combustion burner, characterized in that, It includes a combustion head assembly (1), a porous ceramic column (2), and a combined swirl cap (3). The combustion head assembly (1) includes a mounting flange (11), an inner air duct (12), a front end plate (13), an upper plate (14), a lower plate (15), and a rear end plate (16). The front end of the inner air duct (12) is connected to the mounting flange (11) and inserted into the combustion head assembly (1) through a through hole opened on the front end plate (13), and is connected to the front end plate (13). The upper plate (14) of the combustion head assembly (1) has two surfaces with an included angle. A plurality of through holes (141) are evenly distributed on the upper plate (14) surface and at the top of the included angle. A plurality of sleeves (17) are arranged at corresponding positions. The porous ceramic column (2) is placed inside the sleeve (17). The combined swirl cap (3) is arranged on each sleeve (17). The combined swirl cap (3) includes a flame stabilizing disc (31), a swirl vane (32), and a swirl member housing (33). The swirl vane (32) forms an included angle of 30 - 75° with the axial gas outlet direction of the combined swirl cap (3), and the swirl vane (32) is 5 - 10 mm lower than the outer plane of the flame stabilizing disc (31).

2. The ultra-low nitrogen burner head for a horizontally installed vertical combustion burner according to claim 1, characterized in that, A plurality of ventilation holes (121) are arranged from the front end to the rear end of the inner air duct (12). The ventilation holes (121) are densely arranged on the surface of the inner air duct (12). The aperture of the ventilation holes (121) gradually decreases along the axis in the direction from the front end plate (13) to the rear end plate (16). The total opening area of the plurality of ventilation holes (121) is equal to the inlet area of the mounting flange (11).

3. The ultra-low nitrogen combustion head for a horizontally installed vertical combustion burner according to claim 1, characterized in that, The diameter of the ceramic column (2) is between 20 and 40 mm, the height is between 20 and 40 mm, and the diameter of its small holes is between 2 and 3 mm.

4. The ultra-low nitrogen combustion head for a horizontally-mounted vertical combustion burner according to claim 1, characterized in that, The flame stabilizing disc (31) has through holes. The swirl vane (32) is arranged between the flame stabilizing disc (31) and the swirl member housing (33). There are 4 - 16 swirl vanes (32). Each swirl vane (32) is evenly distributed in a ring outside the flame stabilizing disc (31). The flame stabilizing disc (31) is arranged inside the swirl member housing (33) and is 5 - 10 mm lower than the outer edge of the swirl member housing (33).

5. The ultra-low nitrogen burner head for a horizontally-mounted vertical combustion burner according to claim 1, characterized in that, Threads that can be connected to the combined swirl cap (3) are provided on the sleeve (17). The lower surface of the sleeve (17) is a bevel structure, and when it is arranged together with the upper plate (14), it forms a certain angle with the contact surface.

6. The ultra-low nitrogen combustion head for a horizontally-mounted vertical combustion burner according to claim 1, wherein One or more sewage discharge holes are provided on the rear end plate (16).

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