Ultra-low nitrogen gas burner

Abstract

The present invention is an ultra-low nitrogen gas burner, comprising a burner housing, a flame tube, a central gas distributor assembly, a bypass ignition gun assembly, a central gun mechanism, a damper adjustment mechanism assembly and a burner control box, wherein the flame tube is installed at the front end of the burner housing through a rotating flange assembly, the central gas distributor assembly is arranged at the center of the inner cavity of the rotating flange assembly, the bypass ignition gun assembly is fixedly installed on the central gas distributor assembly, the central gun mechanism is arranged at the center of the inner cavity of the central gas distributor assembly, the damper adjustment mechanism assembly is arranged on one side of the burner housing, the gas burner control box is arranged on the other side of the burner housing, the first gas supply channel is connected to the central gas distributor assembly, the second gas supply channel is connected to the central gun mechanism through a central metal hose, and the third gas supply channel is connected to the bypass ignition gun assembly through a bypass ignition metal hose. Beneficial effect: The furnace temperature can be reduced, thereby reducing the generation of NOX.

Description

Technical Field

[0001] The invention relates to the technical field of burners, and in particular to an ultra-low nitrogen gas burner. Background Art

[0002] With the rapid development of society, mankind has entered a period of transition from the industrial civilization era to the ecological civilization era. We should vigorously advocate low-carbon economy and build ecological civilization. my country will face the dual tasks of industrialization and ecologization, and the contradiction between energy demand and environmental pollution will become more and more prominent. The new flue gas emission standards reduce the concentration of smoke, CO, NO X , SO2 emissions. For example, local standards in Beijing and Hebei require that boiler tail gas NO X Less than 30mg; local standards such as Shanghai, Jiangsu, and Zhejiang require boiler tail gas NO X Less than 50mg. Due to the improvement of national policy on emission requirements and the extensive application of various fuel gases, the development of low-nitrogen burners will become an urgent need for energy conservation and environmental protection.

[0003] The mixing head in the gas burner is the key core component of the ultra-low nitrogen burner. At present, in the burner industry at home and abroad, the combustion method adopts diffusion combustion. In order to ensure sufficient combustion of the fuel, the design idea of ​​better mixing of fuel and air is generally adopted. In this combustion method, the flame is more concentrated, the flame temperature is high, and it is easy to produce NO X As the temperature increases, the thermal NO X The amount of NO generated will increase geometrically. X The burner that reduces emissions while meeting national and local standards and ensuring full combustion of fuel and little change in boiler thermal efficiency is a difficult problem that urgently needs to be solved by technicians around the world. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide an ultra-low nitrogen gas burner designed with a graded and segmented flue gas internal circulation combustion structure.

[0005] The technical solution is as follows: an ultra-low nitrogen gas burner, characterized in that it includes a burner housing, a flame tube, a central gas distributor assembly, a bypass ignition gun assembly, a central gun mechanism, a damper adjustment mechanism assembly and a burner control box, wherein the flame tube is installed at the front end of the burner housing through a rotating flange assembly, the central gas distributor assembly is arranged at the center of the inner cavity of the rotating flange assembly, and its front end extends toward the front end of the flame tube, the bypass ignition gun assembly is fixedly installed on the central gas distributor assembly, the central gun mechanism is arranged at the center of the inner cavity of the central gas distributor assembly, and passes through the central gas distributor assembly, the damper adjustment mechanism assembly is arranged on one side of the burner housing, and the gas burner control box is arranged on the other side of the burner housing, the ultra-low nitrogen gas burner also includes a first gas supply channel, a second gas supply channel and a third gas supply channel, the first gas supply channel is connected to the central gas distributor assembly, the second gas supply channel is connected to the central gun mechanism through a central metal hose, and the third gas supply channel is connected to the bypass ignition gun assembly through a bypass ignition metal hose.

[0006] As a further improvement, the central gas distributor assembly includes a central gas ring, a plurality of gas distribution pipes, a first gas spray gun, a second gas spray gun and a flame stabilizing disk. The central gas ring is connected to the first gas supply channel. The plurality of gas distribution pipes are evenly arranged around the outer surface of the central gas ring and enclose a space. The first gas spray gun and the second gas spray gun are staggered on the front end of the gas distribution pipe. The flame stabilizing disk is arranged in the space. A central gun protection tube is provided through the central gas ring, and the front end of the central gun protection tube extends toward the flame stabilizing disk. The central gun mechanism is arranged in the central gun protection tube.

[0007] As a further improvement, the first gas spray gun includes a first spray gun pipe, a first spray hole group is arranged on the outer side of the first spray gun pipe, and a right-angle nozzle is arranged on the inner side of the first spray gun pipe, and the nozzle of the right-angle nozzle is arranged forward.

[0008] As a further improvement, the second gas spray gun includes a second spray gun pipe, a second spray hole group is provided on the outer side of the first spray gun pipe, and a straight nozzle is provided on the inner side of the second spray gun pipe, and the nozzle of the straight nozzle is set into the space.

[0009] As a further improvement, the center gun mechanism includes a center gun air pipe, three center gun air pipes, a swirl disk and a center gun ignition needle. The three center gun air pipes are evenly arranged around the outer surface of the front end of the center gun air pipe. A center gun injection hole is provided on the inside, outside, top and bottom of each of the center gun air pipes. The swirl disk is movably mounted on the center gun air pipe, and the center gun ignition needle is fixedly installed on the front end of the center gun air pipe.

[0010] As a further improvement, the swirl disk is composed of a plurality of fan-shaped swirl plates staggered and spiraled on a sleeve, and a through hole is provided in the center of each swirl plate.

[0011] As a further improvement, three support columns are further provided at the front end of the central gun air pipe, and the three support columns are evenly arranged on the central air pipe.

[0012] As a further improvement, it also includes a flame detector, an air pressure switch, a smoke circulation butterfly valve assembly and an ignition transformer assembly, the flame detector is mounted and fixed on the rotating flange assembly through a flame detection protection cover, the air pressure switch is mounted on the burner housing, the smoke circulation butterfly valve assembly is mounted on the air door adjustment mechanism assembly, and the ignition transformer assembly is mounted on the burner housing.

[0013] Beneficial Effects

[0014] The beneficial effects are: 1. Flame segmentation: the combustion flame is divided into multiple small flame areas, thereby increasing the flame heat dissipation area, reducing the temperature of the center flame peak, and reducing thermal NO X The generation of ultra-low nitrogen burner gas nozzle sprays fuel at multiple angles and levels, forming a multi-flame distribution state in the flame shape, effectively reducing the temperature of the flame root and making the entire flame temperature tend to be evenly distributed.

[0015] 2. Flue gas internal circulation combustion technology: By using a swirler to generate an airflow with tangential velocity, the specific rotating airflow strengthens the turbulent mixing of fuel and air, and at the same time causes a large amount of flue gas to reflux inside the central recirculation zone of the swirl to generate a vortex. The appropriate vortex intensity will produce sufficient radial and axial gradients in the airflow, which will cause the airflow to reverse and produce an annular recirculation area in the center of the flame. The high-temperature gas in the central recirculation area will return to the burner throat, which ensures the ignition of cold unburned gas and reduces NO by lowering the flame temperature and reducing the oxygen partial pressure. X generate.

[0016] 3. Staged combustion: Under the premise that the total air supply of the burner remains unchanged, the air and fuel are sent to the nozzle in stages and layers from the axial and radial directions, so that the combustion produces multiple areas such as the center, axial flow, and swirl flow. The fuel in the central combustion area is in an oxygen-deficient state, and the incompletely burned fuel encounters air and burns again when it diffuses to the periphery. This staged combustion can reduce the peak and average value of the flame temperature. It can reduce the furnace temperature, thereby reducing NO X Generation of.

[0017] 4. Electronic proportional regulation: Through the direct connection between the servo motor and the damper active shaft, the damper opening is accurately controlled to reduce the excess oxygen in the flue gas during the combustion process, thereby inhibiting NO X The precise design of the mixing center gas path allows air and fuel to be mixed most effectively and timely, allowing the combustion process to run as close to the theoretical air volume as possible. This is the most direct and effective way to reduce NO X Reducing excess oxygen in flue gas can inhibit NO X This is the most direct and effective way to reduce NO X Method of emission.

[0018] 5. External circulation of flue gas: The flue gas temperature at the extraction point of the recirculated flue gas should be between 120℃ and 180℃, and the mixed gas temperature at the mixing point of the blower inlet should be less than 55℃. Excess air volume at the furnace inlet is necessary, and reducing the excess air volume is conducive to reducing NO X Generation of. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention is further described below with reference to the accompanying drawings and implementation examples.

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 It is a schematic diagram of the top view of the structure of the present invention;

[0022] Figure 3 for Figure 2 A magnified view of part A;

[0023] Figure 4 It is a schematic diagram of the structure of the central gas distributor assembly of the present invention;

[0024] Figure 5 It is a schematic structural diagram of a bypass ignition gun assembly of the present invention;

[0025] Figure 6 It is a schematic diagram of the structure of the center gun mechanism of the present invention;

[0026] Figure 7 It is a schematic diagram of the structure of the air door adjustment mechanism assembly of the present invention.

[0027] Numbers in the figure:

[0028] 1. Burner housing 2. Flame tube 3. Central gas distributor assembly

[0029] 301, central gas ring 302, gas distribution pipe 303, first gas spray gun

[0030] 3031, first spray gun pipe 3032, right angle nozzle 304, second gas spray gun

[0031] 3041, second spray gun tube 3042, second spray hole group 3043, straight nozzle

[0032] 305, flame stabilizing plate 306, center gun protection tube 4, bypass ignition gun assembly

[0033] 401, double row ignition needles 402, ignition needle pressure plate 403, ignition tube

[0034] 404, ion rod 5, center gun mechanism 501, center gun air pipe

[0035] 502, center gun air pipe 503, swirl disc 5031, swirl sheet

[0036] 5032, sleeve 504, center gun ignition needle 505, support column

[0037] 6. Air door adjustment mechanism assembly 601, servo adjustment motor 602, servo motor bracket

[0038] 603, coupling 604, damper frame assembly 605, air adjustment rod assembly

[0039] 606, connecting block 607, damper shaft 608, damper plate

[0040] 7. Gas burner control box 8. Rotating flange assembly 9. First gas supply channel

[0041] 10. Gas butterfly valve assembly 11. Central metal hose 12. Bypass ignition metal hose

[0042] 13. Flame detector 14. Air pressure switch 15. Smoke circulation butterfly valve assembly

[0043] 16. Ignition transformer assembly DETAILED DESCRIPTION

[0044] In order to have a further understanding and recognition of the structural features and the effects achieved by the present invention, a preferred embodiment and accompanying drawings are used for detailed description as follows:

[0045] like Figure 1-3 As shown, an ultra-low nitrogen gas burner includes a burner housing 1, a flame tube 2, a central gas distributor assembly 3, a bypass ignition gun assembly 4, a central gun mechanism 5, a damper adjustment mechanism assembly 6 and a burner control box 7. The flame tube 2 is installed at the front end of the burner housing 1 through a rotating flange assembly 8. The central gas distributor assembly 3 is arranged at the center of the inner cavity of the rotating flange assembly 8, and its front end faces the flame tube 2. The front end is extended, and the bypass ignition gun assembly 4 is fixedly mounted on the central gas distributor assembly 3. The central gun mechanism 5 is arranged at the center of the inner cavity of the central gas distributor assembly 6 and passes through the central gas distributor assembly 6. The damper adjustment mechanism assembly 6 is arranged on one side of the burner housing 1, and the gas burner control box 7 is arranged on the other side of the burner housing 1. The ultra-low nitrogen gas burner also includes a first gas supply channel 9, a second gas supply channel and a third gas supply channel. The first gas supply channel 9 is connected to the central gas distributor assembly 3 and supplies gas to the central gas distributor assembly separately. A gas butterfly valve assembly 10 is provided on the first gas supply channel 9 to control the entry and blocking of gas. The second gas supply channel is connected to the central gun mechanism 5 through a central metal hose 11 to supply gas to the central gun mechanism 5 separately. The third gas supply channel is connected to the bypass ignition gun assembly 4 through a bypass ignition metal hose 12 to supply gas to the bypass ignition gun 4 separately. The ultra-low nitrogen gas burner also includes a flame detector 13, an air pressure switch 14, a smoke circulation butterfly valve assembly 15 and an ignition transformer assembly 16. The flame detector 13 is fixed on the rotating flange assembly 8 through a fire detection protective cover. The condensed water generated by the flue gas recirculation is blocked outside by the fire detection protective cover, thereby ensuring the long-term normal operation of the combustion equipment. The air pressure switch 14 is installed on the burner housing 1, the smoke circulation butterfly valve assembly 15 is installed on the air door adjustment mechanism assembly 6, and the ignition transformer assembly 16 is installed on the burner housing 1. The burner of the present invention supplies gas to the central gas distributor assembly, the central gun mechanism and the bypass ignition gun assembly through three air supplies, respectively, to achieve graded and segmented combustion. Under the premise that the total air supply of the burner remains unchanged, air and fuel are sent to the nozzle in an axial and radial graded and layered manner, so that the combustion produces multiple areas such as the center, axial flow, and swirl. The fuel in the central combustion area is in an oxygen-deficient state, and the incompletely burned fuel encounters air and burns again when it diffuses to the periphery. This graded and segmented combustion can reduce the peak and average value of the flame temperature. The furnace temperature can be lowered, thereby reducing the generation of NOX.

[0046] Specifically, Figure 4As shown, the central gas distributor assembly 3 includes a central gas ring 301, a plurality of gas distribution pipes 302, a first gas spray gun 303, a second gas spray gun 304 and a flame stabilizing disk 305. The central gas ring 301 is connected to the first gas supply channel 9. The plurality of gas distribution pipes 301 are evenly arranged around the outer surface of the central gas ring and enclose a space. The first gas spray gun 303 and the second gas spray gun 304 are staggered on the front end of the gas distribution pipe. The flame stabilizing disk 305 is arranged in the space. A central gun protection tube 306 is provided through the central gas ring 301, and the front end of the central gun protection tube 306 extends toward the flame stabilizing disk 305. The central gun mechanism 6 is arranged in the central gun protection tube 306.

[0047] The first gas spray gun 303 includes a first spray gun pipe 3031, on the outer side of which a first spray hole group (not shown in the figure) is provided, and on the inner side of the first spray gun pipe 3031 a right-angle nozzle 3032 is provided, and the nozzle of the right-angle nozzle 3032 is arranged forward. The second gas spray gun 304 includes a second spray gun pipe 3041, on the outer side of the first spray gun pipe 3041 a second spray hole group 3042 is provided, and on the inner side of the second spray gun pipe 3041 a straight nozzle 3043 is provided, and the nozzle of the straight nozzle 3043 is arranged inwardly, and the natural gas sprayed from different angles and directions of the first gas spray gun 303, the second gas spray gun 304, the right-angle nozzle 3032 and the straight nozzle 3043 is fully premixed and layered by the swirl effect of the combustion-supporting air through the flame stabilizing plate 305, and ignited and ignited in the bypass to form a main flame.

[0048] like Figure 5 As shown, the bypass ignition gun assembly 4 is fixed to the central gas distributor assembly 3 by screws through the fixing bracket I 405 and the fixing bracket II 406. The bypass ignition gun assembly 4 includes a double-row ignition needle 401, an ignition needle pressure plate 402, an ignition tube 403 and an ion rod 404. The double-row ignition needle 401 is fixed to the front end of the ignition tube through the ignition needle pressure plate 402. The ion rod 404 is connected to the front end of the double-row ignition needle 401, and its function is to ignite the main fire; the ion rod includes an ignition needle and a ceramic rod. The ignition needle is installed inside the ceramic rod to ensure that the high voltage electricity is disconnected from the outside when the ignition needle is working. One end of the ignition needle is connected through a high-voltage hidden plug and a high-voltage wire, and the other end passes through the cable lock on the fixed burner housing and extends to be fixed on the ignition transformer assembly 15.

[0049] like Figure 6As shown, the center gun mechanism 5 includes a center gun air pipe 501, three center gun air pipes 502, a swirl disk 503 and a center gun ignition needle 504. The three center gun air pipes are evenly arranged around the outer surface of the front end of the center gun air pipe. Center gun injection holes 5021 are provided on the inner side, outer side, top and bottom of each center gun air pipe 502. The swirl disk 503 is movably mounted on the center gun air pipe 501, and the position of the swirl disk 503 can be adjusted forward and backward as needed. The center gun ignition needle 504 is fixedly installed at the front end of the center gun air pipe 501. The function of the center gun mechanism is to fully premix the combustion-supporting air entering from the center pipe through the swirl disk 503 and the natural gas injected from the center gun injection hole 5021 on the center gun air pipe 502, and then ignite it from the bypass ignition point to form a center flame in the center area. The swirl disk 503 is composed of a plurality of fan-shaped swirl plates 5031 staggered and swirled on a sleeve 5032, and a through hole is provided at the center of each swirl plate 5031. Three support columns 505 are also provided at the front end of the central gun gas pipe 501. The three support columns are evenly arranged on the central gas pipe 501 to ensure that the central gun mechanism is located at the center of the central gas distributor assembly 3 when installed. The above structure divides the combustion flame into multiple small flame areas, thereby increasing the flame heat dissipation area, reducing the peak temperature of the central flame, and reducing the thermal NO X Generation; The ultra-low nitrogen burner gas nozzle sprays fuel at multiple angles and levels, forming a multi-flame distribution state in the flame shape, effectively reducing the temperature of the flame root and making the entire flame temperature tend to be evenly distributed. By using a swirl disk to generate an airflow with a tangential velocity, the specific rotating airflow enhances the turbulent mixing of the fuel and the air, and at the same time causes a large amount of flue gas to reflux inside the central recirculation zone of the swirl to generate a vortex. The appropriate vortex intensity will produce sufficient radial and axial gradients in the airflow, which will cause the airflow to reverse and produce an annular recirculation area in the center of the flame. The high-temperature gas in the central recirculation area will return to the burner throat, which ensures the ignition of the cold unburned gas, while reducing NO by lowering the flame temperature and reducing the oxygen partial pressure. X generate.

[0050] like Figure 7As shown, the damper adjustment mechanism assembly 6 includes a servo adjustment motor 601, a servo motor bracket 602, a coupling 603, a damper frame assembly 604, an air adjustment rod assembly 605, a connecting block 606, a damper shaft 607, and a damper plate 608. During installation, the diamond bearing is first fixed to the damper frame assembly 604, and the damper shaft 607 passes through the diamond bearing. After adjusting the position of the damper shaft 607, the screws on the diamond bearing are tightened, and then the damper plate 608 is fixed to the damper shaft 607. The servo adjustment motor 601 is connected to the damper shaft 607 through the coupling 603 and fixed to the damper frame assembly 604; the air adjustment rod assembly 605 connects the two damper shafts 607 through the connecting block 606 and the connecting screws. The damper plate is controlled to be in a horizontal position by slightly adjusting the length of the air adjustment rod, and at the same time, it is ensured that the damper rotates freely without being stuck. The servo motor is directly connected to the damper active shaft to accurately control the damper opening, reduce the excess oxygen in the flue gas during the combustion process, and thus inhibit NO X The precise design of the mixing center gas path allows air and fuel to be mixed most effectively and timely, allowing the combustion process to run as close to the theoretical air volume as possible. This is the most direct and effective way to reduce NO X Reducing excess oxygen in flue gas can inhibit NO X This is the most direct and effective way to reduce NO X Method of emission.

[0051] The operation procedure of the ultra-low nitrogen gas burner of the present invention is as follows: boiler operation condition verification → gas pressure verification → gas valve group leak detection → large air door furnace purge → air door runs to ignition position → ignition transformer works → ignition solenoid valve runs → ignition flame verification (ignition transformer stops) → main gas valve opens → main fire flame verification (ignition solenoid valve stops) → load ratio adjustment → normal shutdown → furnace post-purge. The flow control valve on the upper part of the burner can continuously deliver gas from small to large to the nozzle to achieve combustion ratio adjustment. The flow control valve is driven by an independent servo motor, and the air door adjustment mechanism is driven by an independent servo motor. The three servo motors are used to automatically adjust the air and gas ratio through the LMV52 Siemens controller.

[0052] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. All equivalent changes and modifications to the shapes, structures, features and spirits described in the claims of the present invention should be included in the scope of the claims of the present invention.

Claims

1. An ultra-low nitrogen gas burner, characterized in that: The invention comprises a burner housing, a flame tube, a central gas distributor assembly, a bypass ignition gun assembly, a central gun mechanism, a damper adjustment mechanism assembly and a burner control box. The flame tube is installed at the front end of the burner housing through a rotating flange assembly. The central gas distributor assembly is arranged at the center of the inner cavity of the rotating flange assembly, and its front end extends toward the front end of the flame tube. The bypass ignition gun assembly is fixedly installed on the central gas distributor assembly. The central gun mechanism is arranged at the center of the inner cavity of the central gas distributor assembly and passes through the central gas distributor assembly. The damper adjustment mechanism The assembly is arranged on one side of the burner housing, and the burner control box is arranged on the other side of the burner housing. The ultra-low nitrogen gas burner also includes a first gas supply channel, a second gas supply channel and a third gas supply channel. The first gas supply channel is connected to the central gas distributor assembly, the second gas supply channel is connected to the central gun mechanism through a central metal hose, and the third gas supply channel is connected to the bypass ignition gun assembly through a bypass ignition metal hose. The central gas distributor assembly includes a central gas ring, a plurality of gas distribution pipes, a first gas spray gun, a second gas spray gun and a flame stabilizing disk. The central gas ring The central air ring is connected to the first air supply channel, the plurality of gas distribution pipes are evenly arranged around the outer surface of the central air ring and enclose a space, the first gas spray gun and the second gas spray gun are staggered on the front end of the gas distribution pipe, the flame stabilizing disk is arranged in the space, a central gun protection tube is arranged through the central air ring, and the front end of the central gun protection tube extends toward the flame stabilizing disk, and the central gun mechanism is arranged in the central gun protection tube; the central gun mechanism includes a central gun air pipe, three central gun air pipes, a swirl disk and a central gun ignition needle, and the three central gun air pipes are arranged around the front end of the central gun air pipe. The outer surface of the end is evenly arranged around, and center gun injection holes are provided on the inner side, outer side, top and bottom of each center gun air pipe. The swirl disk is movably sleeved on the center gun air pipe, and the center gun ignition needle is fixedly installed at the front end of the center gun air pipe; the swirl disk is composed of a plurality of fan-shaped swirl sheets staggered and spiraled on a sleeve, and a through hole is provided in the center of each swirl sheet. The first gas spray gun includes a first spray gun pipe, a first injection hole group is provided on the outer side surface of the first spray gun pipe, and a right-angle nozzle is provided on the inner side surface of the first spray gun pipe, and the nozzle of the right-angle nozzle is arranged forward.

2. The ultra-low nitrogen gas burner according to claim 1, characterized in that: The second gas spray gun comprises a second spray gun pipe, a second spray hole group is arranged on the outer side of the first spray gun pipe, and a straight nozzle is arranged on the inner side of the second spray gun pipe, and the nozzle of the straight nozzle is arranged in the space.

3. The ultra-low nitrogen gas burner according to claim 1, characterized in that: Three support columns are also provided at the front end of the central gun air pipe, and the three support columns are evenly arranged on the central air pipe.

4. The ultra-low nitrogen gas burner according to claim 1, characterized in that: It also includes a flame detector, an air pressure switch, a smoke circulation butterfly valve assembly and an ignition transformer assembly. The flame detector is fixed on the rotating flange assembly through a flame detection protection cover, the air pressure switch is installed on the burner housing, the smoke circulation butterfly valve assembly is installed on the air door adjustment mechanism assembly, and the ignition transformer assembly is installed on the burner housing.

Images