Long and short flame combined flameless burner

Abstract

The utility model belongs to the technical field of combustors, and discloses a long and short flame combined flameless combustor which is provided with a wind shell, a fuel gas inlet channel and an air inlet channel are arranged outside the wind shell, and a long flame air inlet channel and a short flame air inlet channel are arranged in the wind shell. A long flame gas spray gun is arranged in the long flame air inlet channel, a first gas mixing device is arranged on the burner block between the right end of the long flame air inlet channel and the long flame gas spray gun, and a short flame gas spray gun is arranged in the short flame air inlet channel. A second gas mixing device is arranged between the right end of the short flame air inlet channel and the short flame gas spray gun; the long flame capacity and the short flame capacity are convenient to adjust, the wide furnace profile is more uniform in furnace temperature in the furnace width direction, the combustion stability is better, the preheating air temperature is 500 DEG C or below, and NOx can be discharged at the furnace temperature of 1300 DEG C; the NOx emission result of the existing steel rolling heating furnace is met; 150 mg / m < 3 >.

Description

Technical Field

[0001] This utility model belongs to the field of burner technology, and in particular discloses a flameless burner that combines long and short flames. It features convenient adjustment of long and short flame capabilities, a wide furnace shape for more uniform furnace temperature across the furnace width, better combustion stability, and NOx emissions of <120mg / m³ at a furnace temperature of 1300℃ when the preheated air temperature is 500℃ or below. 3 This meets the requirement of NOx emissions <150mg / m³ for existing steel rolling heating furnaces. 3 Require. Background Technology

[0002] Currently, in some industries, heating furnaces and heat treatment furnaces often suffer from uneven central temperatures due to the wide furnace width and insufficient flame length of most burners. This results in variations in the heating temperature of steel components. Therefore, it is necessary to install flat-flame burners on the furnace top to create a uniform temperature field over a relatively large area. However, installing flat-flame burners on the furnace top has both advantages and disadvantages. The larger burner bricks make the burners very heavy, requiring structural reinforcement. Furthermore, the higher temperature at the furnace top prevents workers from operating there, hindering real-time burner operation and adjustment. Additionally, the installation of flat-flame burners on the furnace top increases heat loss. Based on these reasons, our company has designed and developed a flameless burner combining long and short flames, which eliminates the need for flat-flame burners on the furnace top, meeting the combustion and heating requirements of wide-furnace designs.

[0003] In the prior art, CN115727328A discloses a gas fuel burner with both long and short flames, its control method, and a heating furnace. This gas fuel burner with both long and short flames includes an air intake main pipe, a fuel intake main pipe, a short flame gas nozzle, a short flame air nozzle, a long flame gas nozzle, and a long flame air nozzle. The air intake main pipe is connected to the short flame air nozzle and the long flame air nozzle, and the fuel intake main pipe is also connected to the short flame gas nozzle and the long flame gas nozzle.

[0004] The above-mentioned existing technology has the following defects: 1. It cannot observe the flame status in the furnace in real time; 2. The fuel regulating baffle is located on the main fuel inlet pipe and cannot separately regulate the flow rate of the gas in the first gas inlet branch pipe and the second gas inlet branch pipe. The air regulating baffle is located on the main air inlet pipe and cannot separately regulate the flow rate of the air in the long flame air chamber and the short flame air chamber. Utility Model Content

[0005] To address the aforementioned problems, the purpose of this invention is to disclose a flameless burner combining long and short flames. The long flame, designed according to the furnace width, selects the required air and fuel gas pressures to achieve flameless combustion. Simultaneously, the long flame airflow can entrain low-oxygen furnace gas, reducing NOx formation and enabling flameless combustion at high temperatures. The short flame compensates for the combustion space created by the flameless combustion of the long flame, while also providing root ignition for stable combustion. This is achieved through the following technical solution.

[0006] A flameless burner combining long and short flames has a wind shell, with a gas intake passage and an air intake passage outside the wind shell, and a long flame air intake passage and a short flame air intake passage inside the wind shell. The left ends of the long flame air intake passage and the left ends of the short flame air intake passage are respectively connected to the same end of the air intake passage.

[0007] A long flame gas nozzle is provided in the long flame air intake channel, and a first gas mixing device is provided between the right end of the long flame air intake channel and the long flame gas nozzle. A short flame gas nozzle is provided in the short flame air intake channel, and a second gas mixing device is provided between the right end of the short flame air intake channel and the short flame gas nozzle.

[0008] The left ends of the long-flame gas nozzle and the short-flame gas nozzle are respectively connected to the same end of the gas intake channel.

[0009] The aforementioned flameless burner combining long and short flames comprises a first mixing device consisting of a long flame air small-angle swirl plate and a positioning sleeve. The right end of the long flame air intake channel is fixed to the long flame gas nozzle via the positioning sleeve. The long flame gas nozzle is located in the middle of the long flame air intake channel. A long flame air small-angle swirl plate is provided inside the positioning sleeve, and the long flame air small-angle swirl plate is connected to the long flame gas nozzle bushing.

[0010] The aforementioned flameless burner combining long and short flames includes a second mixing device consisting of a short flame air secondary air eyelet brick and a short flame air primary air swirl plate. The short flame air secondary air eyelet brick is fixed to the short flame air inlet channel, and the short flame air primary air swirl plate is located in the middle of the short flame air secondary air eyelet brick. The short flame air secondary air eyelet brick is provided with an eyelet that connects the short flame air inlet channel and the short flame air-fuel mixture channel. The short flame air primary air swirl plate is connected to the short flame gas nozzle bushing.

[0011] The aforementioned flameless burner combining long and short flames has a burner brick at the right end of the air casing. Inside the burner brick is a long flame air-fuel mixture channel that is connected to the right end of the long flame air intake channel and has an airflow contraction shape, and a short flame air-fuel mixture channel that is connected to the right end of the short flame air intake channel. The short flame air-fuel mixture channel has a flame diffusion funnel shape.

[0012] The aforementioned flameless burner combining long and short flames also includes an auxiliary ignition burner on the left side of the air casing, which is connected to the air-fuel mixture passage of the short flame.

[0013] The aforementioned flameless burner combining long and short flames has an L-shaped air intake channel for both the long and short flames. The horizontal sections of the long and short flame air intake channels are parallel. The long flame gas nozzle is located within the horizontal section of both the long and short flame air intake channels. The left end of the long flame gas nozzle is connected to the lower end of the gas intake channel via an L-shaped long flame gas channel, and the left end of the short flame gas nozzle is connected to the lower end of the gas intake channel via an L-shaped short flame gas channel. A long flame gas regulating valve is installed in the vertical section of both the long and short flame gas channels.

[0014] The aforementioned flameless burner combining long and short flames has a viewing hole at the left end of the horizontal section of the long flame gas passage and at the left end of the horizontal section of the short flame gas passage.

[0015] The air pressure of the aforementioned flameless burner combining long and short flames is selected from 2000Pa to 6000Pa based on the furnace width and the design pressure of the pipeline system.

[0016] The aforementioned flameless burner combining long and short flames has a gas pressure of 4000Pa~20000Pa selected according to the furnace width and pipeline system design pressure.

[0017] The aforementioned flameless burner combining long and short flames has an air temperature design range of room temperature to 550℃.

[0018] The aforementioned flameless burner combining long and short flames has a gas temperature design range of ambient temperature to 250℃.

[0019] The aforementioned flameless burner combining long and short flames can be supplied with low-calorific-value blast furnace gas, producer gas, mixed gas, coke oven gas, or high-calorific-value natural gas and liquefied petroleum gas through its gas inlet channel.

[0020] This application has the following beneficial effects:

[0021] 1. The long flame forms a flameless combustion state, and the long flame airflow can entrain low oxygen furnace gas in the furnace, reducing NOx generation. Flameless combustion can be achieved when the furnace temperature is above 900℃, and the furnace temperature is more uniform.

[0022] 2. A short flame can compensate for the combustion space created by the ignition of a long flame, while also providing root ignition for stable combustion.

[0023] 3. It features convenient adjustment of flame length and shape, and its wide furnace design ensures more uniform furnace temperature and better combustion stability. With preheated air temperatures of 500℃ or below, NOx emissions are kept below 120 mg / m³ at a furnace temperature of 1300℃. 3 This meets the requirement of NOx emissions <150mg / m³ for existing steel rolling heating furnaces. 3 Require.

[0024] 4. No flat flame burners are installed on the furnace top, resulting in less heat loss from the furnace top. The furnace top structure and construction are simple, and installation and use are convenient.

[0025] 5. The system employs a long-flame air small-angle swirl plate, a short-flame air secondary air eye brick, and a short-flame air primary air swirl plate to achieve combined combustion of the fuel gas on the short-flame side and the fuel gas on the long-flame side, resulting in uniform temperature across the furnace width.

[0026] 6. The burner is equipped with an integrated ignition gun and a peep hole to facilitate automated production.

[0027] 7. Equipped with long flame air regulating valve, short flame air regulating valve, long flame gas regulating valve and short flame gas regulating valve, so that the combustion capacity ratio of the long flame side and the short flame side can be easily adjusted according to requirements. Attached Figure Description

[0028] Figure 1 This is a front view of an embodiment of the present utility model.

[0029] Figure 2 This is a schematic cross-sectional view of BB of an embodiment of the present invention.

[0030] Figure 3 This is a schematic cross-sectional view of an embodiment of the present invention.

[0031] Figure 4 This is a left view of an embodiment of the present utility model.

[0032] Figure 5 This is a schematic diagram of the internal structure of an embodiment of the present invention during operation.

[0033] In the figure, the corresponding names of the attached figures are as follows: 1. Gas intake channel, 2. Short flame air-gas mixture channel, 3. Air intake channel, 4. Long flame air intake channel, 5. Long flame air regulating valve, 6. Short flame air intake channel, 7. Short flame air regulating valve, 8. Auxiliary ignition burner, 9. Long flame gas nozzle, 10. Air casing, 11. Long flame gas channel, 12. Short flame gas nozzle, 14. Positioning sleeve, 15. Long flame small angle air swirl plate, 16. Long flame gas nozzle, 17. Long flame air-gas mixture channel, 18. Burner brick, 19. Short flame gas channel, 20. Short flame secondary air eyelet brick, 21. Short flame primary air swirl plate, 22. Short flame gas nozzle, 23. Long flame gas regulating valve, 24. Short flame gas regulating valve, 25. Flame viewing hole. Detailed Implementation

[0034] Example: Figures 1 to 4 A flameless burner combining long and short flames has a wind shell 10, a gas intake channel 1 on the upper left side of the wind shell 10, an air intake channel 3 on the top of the wind shell 10, and a burner brick 18 on the right side of the wind shell 10.

[0035] The air casing 10 has an L-shaped long flame air intake channel 4 and an L-shaped short flame air intake channel 6. The horizontal sections of the long flame air intake channel 4 and the short flame air intake channel 6 are parallel. The left ends of the long flame air intake channel 4 and the short flame air intake channel 6 are connected to the lower end of the air intake channel 3. The long flame air intake channel 4 is equipped with a long flame air regulating valve 5 for adjusting the air flow rate in the long flame air intake channel 4. The short flame air intake channel 6 is equipped with a short flame air regulating valve 7 for adjusting the air flow rate in the short flame air intake channel 6.

[0036] The burner brick 18 has a long flame air-fuel mixture channel 17 connected to the right end of the long flame air intake channel 4 and in the shape of airflow contraction, and a short flame air-fuel mixture channel 2 connected to the right end of the short flame air intake channel 6. The short flame air-fuel mixture channel 2 is in the shape of a flame diffusion funnel.

[0037] A long flame gas nozzle 9 is provided in the horizontal section of the long flame air intake channel 4. The long flame gas nozzle 9 is located in the middle of the horizontal section of the long flame air intake channel 4. The long flame gas nozzle 16 at the right end of the long flame gas nozzle 9 extends into the long flame air-fuel mixture channel 17. A positioning sleeve 14 for fixing the long flame gas nozzle 9 is provided at the right end of the long flame air intake channel 4. A long flame air small angle swirl disk 15 is provided in the positioning sleeve 14. The long flame air small angle swirl disk 15 is connected to the shaft sleeve of the long flame gas nozzle 9.

[0038] A short flame gas nozzle 12 is provided in the horizontal section of the short flame air intake channel 6. The short flame gas nozzle 12 is located in the middle of the horizontal section of the short flame air intake channel 6. The short flame gas nozzle 22 at the right end of the short flame gas nozzle 12 extends into the short flame air-fuel mixture channel 2. A short flame air secondary air vent brick 20 is fixed at the right end of the short flame air intake channel 6. The short flame air secondary air vent brick 20 is provided with an vent that connects the short flame air intake channel 6 and the short flame air-fuel mixture channel 2. A short flame air primary air swirl plate 21 is provided in the middle of the short flame air secondary air vent brick 20. The short flame air primary air swirl plate 21 is connected to the short flame gas nozzle 22 with a bushing.

[0039] The left end of the long flame gas nozzle 9 is connected to the right end of an L-shaped long flame gas channel 11, and the left end of the short flame gas nozzle 12 is connected to the right end of an L-shaped short flame gas channel 19. The long flame gas channel 11 and the short flame gas channel 19 are located on the left side of the air casing 10. The left ends of the long flame gas channel 11 and the short flame gas channel 19 are both connected to the lower end of the gas intake channel 1. The vertical section of the long flame gas channel 11 is provided with a long flame gas regulating valve 23, and the vertical section of the short flame gas channel 19 is provided with a short flame gas regulating valve 24. The left end of the horizontal section of the long flame gas channel 11 and the left end of the horizontal section of the short flame gas channel 19 are each provided with a sighting hole 25.

[0040] On the left side of the air casing 10, there is also an auxiliary ignition burner 8 that is connected to the short flame air-fuel mixture channel 2.

[0041] The aforementioned flameless burner combining long and short flames has an air pressure of 3000 Pa.

[0042] The aforementioned flameless burner combining long and short flames has a gas pressure of 7000 Pa.

[0043] The aforementioned flameless burner combining long and short flames has an air temperature of 450℃.

[0044] The aforementioned flameless burner, which combines long and short flames, uses gas at room temperature.

[0045] The aforementioned flameless burner combining long and short flames has natural gas introduced into the gas intake channel 1.

[0046] Working principle: Short flame burner principle: Gas enters from gas inlet channel 1 and splits into two paths. One path passes through short flame gas regulating valve 24 and enters short flame gas nozzle 12, and is ejected from short flame gas nozzle 22. Air enters from air inlet channel 3 and is also split into two paths. One path passes through short flame air regulating valve 7 and enters short flame air inlet channel 6, where it is further split into two paths. One path is ejected from short flame primary air swirl plate 21, and the other path is ejected from short flame secondary air eyelet brick 20. After the gas and air are ejected through short flame gas nozzle 22, short flame secondary air eyelet brick 20, and short flame primary air swirl plate 21, they are fully mixed and burned in the short flame air-gas mixture channel 2 of burner brick 18 before entering the furnace.

[0047] The principle of long flame burner: After entering through the gas inlet channel 1, the gas passes through the long flame gas regulating valve 23 and enters the long flame gas nozzle 9, and is ejected from the long flame gas nozzle 16. After entering through the air inlet channel 3, the air passes through the long flame air regulating valve 5 and enters the long flame air inlet channel 4, and is ejected from the long flame air small angle swirl plate 15. Because the gas and air have a high velocity after being ejected from the long flame gas nozzle 9 and the long flame air small angle swirl plate 15, they are mixed in a small amount in the long flame air-gas mixing channel 17 of the burner brick 18 and then directly enter the furnace, forming a flameless combustion state. At the same time, the long flame airflow can entrain low oxygen furnace gas in the furnace, reducing NOx generation.

[0048] The auxiliary ignition burner 8 can serve as an ignition source, igniting the short flame burner when the burner starts, thus ensuring the combustion stability of the short flame burner during the heating phase.

[0049] like Figure 5In use, first activate the auxiliary ignition burner 8. Once the auxiliary ignition burner 8 is working normally, open the air and gas valves. Air and gas are injected into the furnace through their respective channels inside the burner. Due to the auxiliary ignition burner 8, the short flame burner ignites first. The flame is ejected from the nozzle of the short flame air-gas mixture channel 2 and mixes near the nozzle in the furnace to form a torch. The flame length of the short flame burner can be adjusted by the short flame gas regulating valve 24 and the short flame air regulating valve 7. At the same time, the air and gas from the long flame burner are also ejected into the furnace through their respective channels inside the burner. However, due to the high flow velocity at the nozzle of the long flame burner, the air and gas enter the furnace at high speed and then come into contact with the torch of the short flame burner to start combustion. Therefore, the flame length formed in the furnace can be longer, ensuring that the temperature at the center of the furnace remains uniform even without using the flat flame burner at the top. Because the gas from the long-flame burner enters the furnace at high speed and diffuses for combustion, when the furnace temperature reaches above 900℃, the flame shape is not visible in the furnace through the sight hole 25, and the entire furnace appears red, forming a flameless combustion state. However, when the furnace temperature is below 900℃, the pale blue torch shape of the short-flame burner can be clearly seen in the furnace through the sight hole 25.

[0050] This application has the following beneficial effects: 1. The long flame forms a flameless combustion state, and at the same time, the long flame airflow can entrain low oxygen furnace gas in the furnace, reducing NOx generation. Flameless combustion can be achieved when the furnace temperature is above 900℃, and the furnace temperature is more uniform.

[0051] 2. A short flame can compensate for the combustion space created by the ignition of a long flame, while also providing root ignition for stable combustion.

[0052] 3. It features convenient adjustment of flame length and shape, and its wide furnace design ensures more uniform furnace temperature and better combustion stability. With preheated air temperatures of 500℃ or below, NOx emissions are kept below 120 mg / m³ at a furnace temperature of 1300℃. 3 This meets the requirement of NOx emissions <150mg / m³ for existing steel rolling heating furnaces. 3 Require.

[0053] 4. No flat flame burners are installed on the furnace top, resulting in less heat loss from the furnace top. The furnace top structure and construction are simple, and installation and use are convenient.

[0054] 5. The system employs a long-flame air small-angle swirl plate, a short-flame air secondary air eye brick, and a short-flame air primary air swirl plate to achieve combined combustion of the fuel gas on the short-flame side and the fuel gas on the long-flame side, resulting in uniform temperature across the furnace width.

[0055] 6. The burner is equipped with an integrated ignition gun and a sight hole, facilitating automated production.

[0056] 7. Equipped with long flame air regulating valve, short flame air regulating valve, long flame gas regulating valve and short flame gas regulating valve, so that the combustion capacity ratio of the long flame side and the short flame side can be easily adjusted according to requirements.

[0057] The above embodiments are merely preferred technical solutions of this utility model and should not be considered as limitations on this utility model. The protection scope of this utility model should be the technical solution described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the protection scope of this utility model.

Claims

1. A flameless burner combining long and short flames, having a wind casing (10), characterized in that: The outer side of the wind shell (10) is provided with a gas intake passage (1) and an air intake passage (3). Inside the wind shell (10) is a long flame air intake passage (4) and a short flame air intake passage (6). The left end of the long flame air intake passage (4) and the left end of the short flame air intake passage (6) are respectively connected to the same end of the air intake passage (3). A long flame gas nozzle (9) is provided in the long flame air intake channel (4), and a first gas mixing device is provided between the right end of the long flame air intake channel (4) and the long flame gas nozzle (9). A short flame gas nozzle (12) is provided in the short flame air intake channel (6), and a second gas mixing device is provided between the right end of the short flame air intake channel (6) and the short flame gas nozzle (12). The left end of the long flame gas nozzle (9) and the left end of the short flame gas nozzle (12) are respectively connected to the same end of the gas inlet channel (1).

2. The flameless burner combining long and short flames according to claim 1, characterized in that: The first mixing device consists of a long flame air small angle swirl plate (15) and a positioning sleeve (14). The right end of the long flame air intake channel (4) is fixed to the long flame gas nozzle (9) through the positioning sleeve (14). The long flame gas nozzle (9) is located in the middle of the long flame air intake channel (4). A long flame air small angle swirl plate (15) is provided inside the positioning sleeve (14). The long flame air small angle swirl plate (15) is connected to the bushing of the long flame gas nozzle (9).

3. A flameless burner combining long and short flames according to claim 2, characterized in that: The second mixing device consists of a short flame air secondary air eyelet brick (20) and a short flame air primary air swirl plate (21). The short flame air secondary air eyelet brick (20) is fixed to the short flame air intake channel (6). The short flame air primary air swirl plate (21) is located in the middle of the short flame air secondary air eyelet brick (20). The short flame air secondary air eyelet brick (20) is provided with an eyelet that connects the short flame air intake channel (6) and the short flame air-fuel mixture channel (2). The short flame air primary air swirl plate (21) is connected to the short flame gas nozzle (22) with a bushing.

4. A flameless burner combining long and short flames according to claim 3, characterized in that: The right end of the air casing (10) is provided with a burner brick (18). Inside the burner brick (18) is a long flame air-fuel mixture channel (17) that is connected to the right end of the long flame air intake channel (4) and has an airflow contraction shape, and a short flame air-fuel mixture channel (2) that is connected to the right end of the short flame air intake channel (6). The short flame air-fuel mixture channel (2) is in the shape of a flame diffusion funnel.

5. A flameless burner combining long and short flames according to claim 4, characterized in that: An auxiliary ignition burner (8) is also provided on the left side of the air casing (10) and is connected to the short flame air-fuel mixture passage (2).

6. A flameless burner combining long and short flames according to claim 5, characterized in that: The long flame air intake channel (4) is L-shaped, and the short flame air intake channel (6) is L-shaped. The horizontal sections of the long flame air intake channel (4) and the short flame air intake channel (6) are parallel. The long flame gas nozzle (9) is located in the horizontal section of the long flame air intake channel (4), and the short flame gas nozzle (12) is located in the horizontal section of the short flame air intake channel (6). The left end of the long flame gas nozzle (9) is connected to the lower end of the gas intake channel (1) through an L-shaped long flame gas channel (11), and the left end of the short flame gas nozzle (12) is connected to the lower end of the gas intake channel (1) through an L-shaped short flame gas channel (19). The vertical section of the long flame gas channel (11) is equipped with a long flame gas regulating valve (23), and the vertical section of the short flame gas channel (19) is equipped with a short flame gas regulating valve (24).

7. A flameless burner combining long and short flames according to claim 6, characterized in that: A viewing hole (25) is provided at the left end of the horizontal section of the long flame gas passage (11) and at the left end of the horizontal section of the short flame gas passage (19).

8. A flameless burner combining long and short flames according to claim 7, characterized in that: The air pressure is selected from 2000Pa to 6000Pa based on the furnace width and the design pressure of the pipeline system, and the gas pressure is selected from 4000Pa to 20000Pa based on the furnace width and the design pressure of the pipeline system.

9. A flameless burner combining long and short flames according to claim 8, characterized in that: The design temperature range for air is room temperature to 550℃, and the design temperature range for gas is room temperature to 250℃.

10. A flameless burner combining long and short flames according to claim 9, characterized in that: The gas introduced into the gas intake channel (1) is gaseous fuel.

Images