A universal full-time ultra-low nitrogen burner

Abstract

The present invention relates to the technical field of burners, and in particular to a universal full-time ultra-low nitrogen burner, comprising: a combustion assembly, the combustion assembly comprising a combustion tube and an outer tube mounted on its outer layer, the cavity formed between the combustion tube and the outer tube being connected to a return air cavity, a combustion chamber being arranged in the combustion tube, the inlet end of the combustion chamber being respectively connected to a powder inlet, a plasma igniter and a purge assembly; a tempering nozzle, arranged on the inner wall of the combustion chamber outlet end, and its air inlet being connected to the cavity between the combustion tube and the outer tube, and its air outlet being connected to the combustion chamber and opposite to the powder inlet direction; a tempering channel, arranged on the inner wall of the combustion chamber, between the tempering air outlet of the tempering nozzle and the purge air outlet of the purge assembly, and having openings at both ends connected to the combustion chamber, for solving the technical problem in the prior art that the continuous operation of the burner needs to rely on a plasma igniter, resulting in low combustion efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of burners, in particular to a universal full-time ultra-low nitrogen burner. Background Art

[0002] A thermal power plant is a factory that uses fuel to produce electricity. The most commonly used fuel is pulverized coal. A burner is a device that sprays pulverized coal fuel and air in a certain way for mixed combustion. Conventional burners use plasma igniters for ignition. During the combustion process, the plasma igniter needs to keep working continuously to ignite the continuously input pulverized coal and ensure the stable operation of the burner. However, the plasma igniter consumes a lot of energy. Long-term use not only consumes a lot of energy, but also the cathode and anode components of the plasma igniter are consumables. The long service life period and high replacement frequency cause a significant increase in the cost of power generation. If the plasma igniter is replaced, the burner needs to stop and wait, and restarting it will also increase the operating cost of the overall equipment.

[0003] The prior art discloses a pulverized coal internal combustion burner with a self-sustaining stable combustion function, which is a new patent with a publication number of CN216244250U. It discloses a combustion shell and an igniter, wherein one end of the combustion shell is a primary air inlet, and the other end of the combustion shell is a combustion nozzle. An ignition hood and a stable combustion cylinder are installed inside the combustion shell, and the igniter is placed inside the ignition hood, and the outlet of the ignition hood is sleeved in the stable combustion cylinder; a ventilation pipe is installed in the stable combustion cylinder, and regenerative combustion gas is passed through the ventilation pipe, and a nozzle is installed at the air outlet end of the ventilation pipe, and the outlet of the nozzle is opposite to the outlet of the ignition hood, and the air inlet end of the ventilation pipe is located at the outlet end of the stable combustion cylinder, and the outlet of the stable combustion cylinder is opposite to the combustion nozzle. There are still many problems with related technologies including the above-mentioned technical solutions, such as: ① The structure is complex, and it is still easy for coal powder to be insufficiently burned and cause sedimentation. In addition, the internal structure is prone to wind resistance, resulting in poor flow of internal coal powder combustion and increased equipment operating costs; ② The flame spray angle of the flame nozzle cannot be adjusted, and the flame center height of the large furnace cannot be adaptively adjusted. Therefore, when there are many layers of burners, if the flame nozzle cannot be adjusted, the flame nozzle can only be installed in the lower layer. Not only is the installation position limited, but the flame spray center cannot be adjusted, affecting the combustion performance of the burner. Summary of the invention

[0004] The object of the present invention is to provide a universal full-time ultra-low nitrogen burner, which is used to solve the technical problem in the prior art that the continuous operation of the burner needs to rely on a plasma igniter, resulting in low combustion efficiency.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A universal full-time ultra-low nitrogen burner, comprising:

[0007] A combustion assembly, the combustion assembly comprises a combustion tube and an outer tube sleeved on the outer layer thereof, the cavity formed between the combustion tube and the outer tube is connected to the return air cavity, a combustion chamber is arranged in the combustion tube, and the inlet end of the combustion chamber is respectively connected to a powder inlet, a plasma igniter and a purge assembly;

[0008] The tempering nozzle is arranged on the inner wall of the combustion chamber outlet end, and its air inlet is connected with the cavity between the combustion tube and the outer tube, and its air outlet is connected with the combustion chamber and opposite to the powder feeding direction;

[0009] The backfire channel is arranged on the inner wall of the combustion chamber between the backfire air outlet of the backfire nozzle and the purge air outlet of the purge assembly, and the backfire channel is a structure with openings at both ends connected to the combustion chamber, and is used to provide a channel for the backflow air blown out by the backfire nozzle to suck the flame in the combustion chamber and then circulate toward the inlet end of the combustion chamber.

[0010] Furthermore, the tempering air outlet of the tempering nozzle, the tempering channel and the purge air outlet of the purge assembly are all located in the upper half of the combustion chamber, the cross-section of the tempering channel accounts for 1 / 5 to 1 / 2 of the cross-sectional area of ​​the combustion chamber, the outlet of the plasma igniter is located in the lower half of the combustion chamber, and the powder inlet is located at the bottom of the combustion chamber.

[0011] Furthermore, a slit opening is provided at the bottom of the tempering channel, and the slit opening is used to connect the tempering channel and the combustion chamber.

[0012] Furthermore, a cooling cavity is arranged inside the backfire channel, an inlet of the cooling cavity is communicated with the cavity between the combustion tube and the outer tube, and an outlet of the cooling cavity is communicated with the combustion chamber.

[0013] Furthermore, the purge assembly includes a purge air inlet pipe and a buffer air chamber, one end of the buffer air chamber is connected to the purge air inlet pipe, and a guide block is installed at the other end. A channel is provided in the guide block, one end of the channel is connected to the buffer air chamber, and the other end is connected to the combustion chamber through the purge air outlet. The guide block is used to provide guidance for the circulating flame flowing out of the backfire channel outlet.

[0014] Furthermore, an end seat is provided at the inlet end of the outer cylinder for sealing the inlet end of the outer cylinder, the purge air inlet pipe of the purge assembly and the plasma generator bracket both pass through the end seat, a plasma igniter whose outlet is connected to the combustion chamber is installed in the plasma generator bracket, and the buffer air cavity is located in a return air cavity surrounded by the end cover, the combustion cylinder and the outer cylinder.

[0015] Furthermore, a surface of the guide block facing the combustion chamber is configured as a concave arc surface, and the arc surface is used to form a smooth transition between the inner wall of the combustion tube and the outlet of the plasma generator bracket.

[0016] Furthermore, an air chamber is arranged on the outer side wall of the end seat, and the air chamber is provided with an air inlet hole connected to an external air source, and the air chamber is connected to the return air cavity and the inlet of the purge air inlet pipe.

[0017] Furthermore, the burner has a flame nozzle installed at the fire outlet, including:

[0018] A primary air duct, one end of which is connected to the furnace of the burner and is used to discharge the primary air;

[0019] The swing ring plate is mounted on the air outlet of the primary air duct and is swingably installed relative to the primary air duct;

[0020] The secondary air duct is mounted on the outer side of the swing ring plate and fixedly installed relative to the swing ring plate, and a cavity is formed between the secondary air duct and the swing ring plate for discharging the secondary air;

[0021] The swing shaft is fixedly installed relative to the swing ring plate and is installed at the power end of the swing power unit. The swing power unit is used to drive the swing ring plate to swing relative to the primary air duct.

[0022] Furthermore, a connecting shaft is arranged in the middle of the side surface of the swing ring plate, a connecting block is arranged at the corresponding position of the primary air duct, the connecting shaft is rotatably mounted on the connecting block, and the swing shaft is arranged on the upper side or the lower side of the connecting shaft.

[0023] Furthermore, a curved convex portion is arranged on the outer side of the primary air duct, and the curved convex portion takes the center of the connecting shaft as the center of the circle. A curved matching portion is arranged on the end of the swinging ring plate, and the curvature of the curved matching portion is the same as that of the curved convex portion, so that when the swinging ring plate swings, the gap between the swinging ring plate and the primary air duct is always consistent.

[0024] Furthermore, a necking portion and an outward expansion portion are provided at the air outlet of the swing ring plate, wherein the necking portion is an end portion extending in a direction of reducing the diameter, and the outward expansion portion is an end portion extending in a direction of expanding the diameter, and the outward expansion portion protrudes from the necking portion in the axial direction, and an end face extending in the radial direction is formed between the necking portion and the outward expansion portion, and the area formed between the end face and the outward expansion portion and the necking portion is a reflow zone, and the angle between the outward expansion portion and the necking portion is an obtuse angle α, and the value range of the obtuse angle is: 90°<α<135°.

[0025] Furthermore, the swing ring plate and the secondary air duct are relatively fixedly installed through a plurality of connecting parts, or are connected by welding. The outlet ends of the secondary air duct and the swing ring plate are both set to be conical. The connecting part adopts a plate-like structure. The number of connecting parts is eight and is distributed on the four sides of the swing ring plate. One side of the connecting part is vertically fixedly connected to the swing ring plate, and the other side is vertically fixedly connected to the secondary air duct.

[0026] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0027] (1) The present invention arranges a backfire nozzle and a backfire channel in the combustion chamber, so that part of the flame in the combustion chamber is sucked back through the backfire channel to the inlet end of the combustion chamber, and then the pulverized coal continuously fed into the inlet end is ignited, thereby achieving the purpose of full-time low nitrogen. When the burner of the present invention is working, the plasma igniter can stop working after the initial working time. The combustion chamber relies on the coordination of the backfire nozzle, the backfire channel and various components in the combustion chamber to realize the circulation of part of the flame, which can not only ensure the full and stable combustion of the pulverized coal in the combustion chamber, but also greatly reduce the working time of the plasma igniter and reduce the operating cost of the burner;

[0028] (2) The present invention sets a cooling cavity for the backfire channel, a buffer air cavity for the purge assembly, and a guide block. The coordinated cooperation of multiple components greatly reduces the high temperature effect caused by the flame circulation in the combustion chamber, effectively ensuring the normal operation of various components of the burner;

[0029] (3) The present invention provides a purge assembly, which cooperates with the backfire nozzle and the backfire channel, which is beneficial to the flow of flame circulation in the combustion chamber. At the same time, it can also purge and remove the coal slag that sinks from the gap of the backfire channel and the coal slag in the combustion chamber, thereby preventing the coal slag from settling and ensuring the normal operation of the entire burner;

[0030] (4) The present invention achieves synchronous swinging of the swinging ring plate and the secondary air duct by arranging a swinging ring plate between the primary air duct and the secondary air duct, and arranging the swinging ring plate to be able to swing around the primary air duct, thereby achieving adjustment of the outlet angles of the primary air and the secondary air, and thus achieving adjustment of the center height of the burner flame; by arranging the arc convex portion of the primary air duct and the arc matching portion of the swinging ring plate, it can ensure that the swinging ring plate swings along the primary air duct while minimizing the gap between the two, thereby reducing heat energy loss; by arranging the constricted portion and the expanded portion of the swinging ring plate, the nozzle wind speed can be ensured while the primary air can be partially supplemented to the recirculation zone, which is beneficial to improving the sufficiency of the primary air combustion and improving the combustion efficiency; by arranging the outlet ends of the secondary air duct and the swinging ring plate to be conical, it is beneficial to ensure the nozzle wind speed of the burner. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the main cross-sectional structure of the present invention;

[0032] Figure 2 for Figure 1 Schematic diagram of the cross-section structure at AA in the middle;

[0033] Figure 3 for Figure 1 Schematic diagram of the cross-section structure at BB in the middle;

[0034] Figure 4is a cross-sectional schematic diagram of the purge assembly of the present invention;

[0035] Figure 5 It is a schematic diagram of the three-dimensional structure of the flame nozzle of the present invention in the front view direction;

[0036] Figure 6 It is a schematic diagram of the three-dimensional structure of the flame nozzle of the present invention in the rear view direction;

[0037] Figure 7 It is a front view of the flame nozzle of the present invention;

[0038] Figure 8 A top view of the flame nozzle of the present invention;

[0039] Fig. 9 It is a right side view of the flame nozzle of the present invention;

[0040] Fig.10 for Figure 7 Schematic diagram of the cross-section structure at CC in the middle;

[0041] Fig.11 for Figure 8 Schematic diagram of the cross-sectional structure at DD in the middle;

[0042] Fig.12 for Fig.11 The schematic diagram of the local enlarged structure at E in the middle;

[0043] Fig.13 This is a schematic diagram of the actual use state of the present invention.

[0044] In the figure, 100, a plasma generator bracket;

[0045] 200, air chamber; 201, air inlet;

[0046] 300, combustion assembly; 301, combustion tube; 302, outer tube; 303, return air cavity; 304, end seat; 305, combustion chamber;

[0047] 400, purge assembly; 401, observation window; 402, purge air inlet pipe; 403, buffer air cavity; 4031, front baffle; 4032, rear baffle;

[0048] 500, guide block; 501, purge air outlet;

[0049] 600, powder inlet;

[0050] 700, tempering channel; 701, cooling chamber; 702, gap opening;

[0051] 800, tempering nozzle; 801, tempering air duct; 8011, tempering air outlet;

[0052] 900, flame nozzle; 901, primary air duct; 9011, arc surface convex part; 902, secondary air duct; 9021, avoidance hole; 903, swing ring plate; 9031, necking part; 9032, outward expansion part; 9033, arc surface matching part; 904, swing shaft; 905, connecting block; 9051, limit plate; 9052, connecting shaft; 906, connecting part;

[0053] 1010. Furnace. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] The drawings are for illustrative purposes only and should not be construed as limiting the present patent;

[0056] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments and are not intended to limit the embodiments of the present application. The singular forms "a", "the" and "the" used in the embodiments of the present application and the appended claims are not intended to limit the embodiments of the present application.

[0057] "The" is also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items.

[0058] When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.

[0059] In the description of this application, it should be understood that the terms "first", "second", "third", etc. are only used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence, nor can they be understood as indicating or implying relative importance. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0060] In addition, in the description of the present application, unless otherwise specified, "plurality" means two or more. "and / or",

[0061] Describing the association relationship of associated objects, it means that there can be three kinds of relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0062] In order to solve the limitations of the prior art, this embodiment provides a technical solution, and the technical solution of the present invention is further described below in conjunction with the drawings and embodiments.

[0063] The present invention is an improvement on the problems of high energy consumption caused by continuous operation of the plasma igniter and low combustion efficiency caused by the inability to adjust the angle of the flame ejected from the flame nozzle 900 in the burner in the related art.

[0064] See attached Figure 1-3 A universal full-time ultra-low nitrogen burner includes a combustion assembly 300, a tempering nozzle 800 and a tempering channel 700. The tempering nozzle 800 and the tempering channel 700 are both located in a combustion chamber 305 of the combustion assembly 300. The specific structures of each part are as follows:

[0065] A combustion assembly 300, which includes a combustion tube 301 and an outer tube 302 mounted on its outer layer. The following inlet end refers to the end close to the coal powder inlet 600, that is, the end away from the flame outlet. A combustion chamber 305 is arranged in the combustion tube 301, and the combustion chamber 305 is used for coal powder combustion. The inlet end of the combustion chamber 305 is respectively connected to the powder inlet 600, a plasma igniter and a purge assembly 400, wherein a plasma igniter whose outlet is connected to the combustion chamber 305 is installed in the plasma generator bracket 100. An end seat 304 is arranged at the inlet end of the outer tube 302 for sealing the inlet end of the outer tube 302. The purge air inlet pipe 402 of the purge assembly 400 and the plasma generator bracket 100 both pass through the end seat 304. The purge assembly 400 includes a purge air inlet pipe 402 and a buffer air cavity 403. An observation window 401 is installed at the inlet of the purge air inlet pipe 402 for real-time observation. The flame burning state in the combustion chamber 305, one end of the buffer air cavity 403 is the front baffle 4031 connected to the purge air inlet pipe 402, and the other end is the rear baffle 4032 to install the guide block 500, the rear baffle 4032 is set to be semicircular and its edge is sealed and installed with the inner wall of the combustion tube 301, the outlet end of the plasma generator bracket 100 is fixedly connected to the bottom of the rear baffle 4032, the powder inlet 600 is located on the bottom wall of the combustion tube 301 and below the outlet end of the plasma generator, a channel is set in the guide block 500, one end of the channel is connected to the buffer air cavity 403, and the other end is connected to the combustion chamber 305 through the purge air outlet 501, the guide block 500 is used to provide guidance for the circulating flame flowing out of the outlet of the tempering channel 700, and the role of the buffer air cavity 403 here is to cool down the high temperature transmitted by the guide block 500 and the plasma generator bracket 100 to prevent long-term high temperature from reducing the service life. Specifically, the top edge of the guide block 500 is fixedly installed on the inner wall of the combustion tube 301, the back side is installed in contact with the rear baffle 4032 of the buffer air cavity 403, and the bottom is fixedly connected to the outlet of the plasma generator. The side of the guide block 500 facing the combustion chamber 305 is set as a concave arc surface, which is used to form a smooth transition between the inner wall of the combustion tube 301 and the outlet of the plasma generator bracket 100. The annular cavity formed between the combustion tube 301 and the outer tube 302 is connected to the return air chamber 303, and the buffer air chamber 403 is located in the return air chamber 303 surrounded by the end cover, the combustion tube 301 and the outer tube 302. The wind chamber 200 is arranged on the outer wall of the end seat 304, and the wind chamber 200 is provided with an air inlet hole 201 connected to an external wind source. At the same time, the wind chamber 200 is connected to the return air chamber 303 and the entrance of the purge air inlet pipe 402. It can be understood that the entrance end of the combustion chamber 305 is respectively connected to the powder inlet 600, the plasma igniter outlet and the purge air outlet 501, and the wind entering the combustion chamber 305 includes two winds from the purge air outlet 501 of the wind chamber 200 and the return air chamber 303.

[0066] The tempering nozzle 800 is arranged on the inner wall of the outlet end of the combustion chamber 305. Here, the tempering nozzle 800 can be fixed by welding or other methods, and the air inlet of the tempering air duct 801 arranged inside it is connected to the cavity between the combustion tube 301 and the outer tube 302, and the air outlet is connected to the combustion chamber 305 and is opposite to the powder feeding direction. Specifically, the tempering air outlet 8011 of the tempering nozzle 800 is set to be a trumpet shape.

[0067] The backfire channel 700 is arranged on the inner wall of the combustion chamber 305 between the backfire outlet 8011 of the backfire nozzle 800 and the purge outlet 501 of the purge assembly 400, and the backfire channel 700 is a structure with openings at both ends connected to the combustion chamber 305. The cross-sectional shape of the backfire channel 700 can be an arc, a triangle or other special-shaped structures, and is used to provide a channel for the backflow wind blown out by the backfire nozzle 800 to suck the flame in the combustion chamber 305 and then circulate to the inlet end of the combustion chamber 305. It can be understood here that the backfire channel 700 is a guide channel, the purpose of which is to guide the wind ejected from the backfire nozzle 800 to suck the flame and then reflux it to the inlet end, and then guide it downward by the arc surface of the guide block 500 to rejoin the burning coal powder flame, and at the same time, ignite the coal powder entering the powder inlet 600 to form a large cycle, and the backflow wind ejected by the backfire nozzle 800 is the power source of the cycle. A slit opening 702 is provided at the bottom of the backfire channel 700, and the slit opening 702 is used to connect the backfire channel 700 and the combustion chamber 305. The purpose of the slit opening 702 here is to prevent the coal powder in the flame from settling and accumulating on the bottom wall inside the backfire channel 700 to cause blockage, and on the other hand, it can adjust the intensity of the flame flowing through the backfire channel 700, and the flame in the combustion chamber 305 can be sucked into the backfire channel 700, or the flame can be returned to the combustion chamber 305 along the slit opening 702. This process depends on the intensity of the return wind. A cooling chamber 701 is provided inside the backfire channel 700, and the inlet of the cooling chamber 701 is connected to the cavity between the combustion tube 301 and the outer tube 302, and the outlet of the cooling chamber 701 is connected to the combustion chamber 305. The purpose of the cooling chamber 701 here is to prevent the high-temperature flame from circulating back for a long time to reduce the service life of the backfire channel 700.

[0068] It should be noted that the tempering outlet 8011 of the tempering nozzle 800, the tempering channel 700 and the purge outlet 501 of the purge assembly 400 are all located in the upper half of the combustion chamber 305, the cross-section of the tempering channel 700 accounts for 1 / 5 to 1 / 2 of the cross-sectional area of ​​the combustion chamber 305, preferably 1 / 3, the outlet of the plasma igniter is located in the lower half of the combustion chamber 305, and the powder inlet 600 is located at the bottom of the combustion chamber 305. Specifically, the relationship between the distance h between the purge outlet 501 and the top of the inner wall of the combustion chamber 305, the distance L between the lowest end of the tempering channel 700 and the top of the inner wall of the combustion chamber 305, the distance H between the tempering nozzle 800 and the top of the inner wall of the combustion chamber 305, and the radius R of the cross-section of the combustion chamber 305 is: h<H<L<R, and the relationship between the minimum diameter D at the tempering outlet 8011 of the tempering nozzle 800 and the diameter d of the purge outlet 501 is: D=8~16d.

[0069] When the burner disclosed in the present invention is working, coal powder enters the combustion chamber 305 of the combustion tube 301 from the powder inlet 600, and the plasma igniter works to ignite the coal powder. At this time, the flame ignited in the combustion chamber 305 is pushed toward the outlet, and at the same time, the wind of the return air cavity 303 is ejected from the tempering air outlet 8011 of the tempering nozzle 800, sucking and blowing part of the flame in the combustion upward to the tempering channel 700, and flowing back to the inlet end of the combustion chamber 305 through the tempering channel 700, and guided downward by the guide block 500 to re-add the coal powder entering from the powder inlet 600 and ignite the coal powder and continue to push it forward, and the flame in the combustion chamber 305 forms a large cycle, and the plasma igniter can be turned off after it is stable. Long-term use is not only conducive to ensuring stable and sufficient combustion in the combustion chamber 305, but also greatly reduces the energy consumption of the plasma igniter, while extending the service life of the plasma igniter and reducing the frequency of replacement of the plasma igniter.

[0070] See attached Fig.13 In the present invention, the outlet of the burner is connected to the furnace 1010, and the flame is ejected from the combustion tube 301 of the combustion assembly 300, passes through the furnace 1010, and then is ejected from the flame nozzle 900, see the attached Figure 5-12The flame nozzle 900 includes: a primary air duct 901, a swing ring plate 903, a secondary air duct 902 and a swing shaft 904. The outlet ends of the secondary air duct 902 and the swing ring plate 903 are both set to a cone, which is conducive to ensuring the wind speed of the flame nozzle 900 of the burner. Specifically, the primary air duct 901 is a rectangular channel, one end of which is connected to the furnace of the burner for discharging primary air, and the other end is a primary air outlet; the swing ring plate 903 is set at the outlet of the primary air duct 901 and is connected to the primary air duct. 901 is relatively swing-mounted, and the swing ring plate 903 is set in a rectangular parallelepiped shape. It can be understood that a connecting shaft 9052 is set in the middle of the side of the swing ring plate 903, and a connecting block 905 is set at the corresponding position of the primary air duct 901. The connecting shaft 9052 is rotatably mounted on the connecting block 905, and the swing ring plate 903 can be swung up and down along the connecting shaft 9052. The swing shaft 904 is set on the upper side or the lower side of the connecting shaft 9052, and the swing shaft 904 is fixedly installed relative to the swing ring plate 903 and is installed on the swing The power end of the power unit, the swing power unit is used to drive the swing ring plate 903 to swing relative to the primary air duct 901. It can be understood that the swing power unit can use a cylinder or other linear power mechanism to drive the connecting rod to make a linear motion, and the power end of the connecting rod is rotatably installed with the swing shaft 904; the secondary air duct 902 is sleeved on the outside of the swing ring plate 903 and is relatively fixedly installed with the swing ring plate 903. It can be understood that the swing ring plate 903 and the secondary air duct 902 are relatively fixedly installed through a plurality of connecting parts 906, or are welded. In this embodiment, the connecting part 906 adopts a plate-like structure, and the number of connecting parts 906 is eight, which are distributed on the four sides of the swing ring plate 903. One side of the connecting part 906 is vertically fixedly connected to the swing ring plate 903, and the other side is vertically fixedly connected to the secondary air duct 902, which is beneficial to ensure the stability between the swing ring plate 903 and the secondary air duct 902, and at the same time does not hinder the flow of secondary air, and is also beneficial to avoid deformation of both in a high-temperature working environment and affecting normal work. A cavity is formed between the secondary air duct 902 and the swing ring plate 903 for discharging secondary air. Here, the secondary air duct 902 is connected to the external casing of the burner. A limit plate 9051 is arranged on the connecting block 905. The limit plate 9051 is arranged vertically to the connecting block 905. Here, the limit plate 9051 is installed in contact with the inner wall of the casing. The setting of the limit plate 9051 is beneficial to improving the stability during the overall swing. The secondary air duct 902 is provided with an avoidance hole 9021. The avoidance hole 9021 is convenient for installing the connecting shaft 9052 and avoiding the connecting block 905 and the limit plate 9051.

[0071] See attached Figure 7 and 12A curved convex portion 9011 is arranged on the outer side of the primary air duct 901, and the curved convex portion 9011 takes the center of the connecting shaft 9052 as the center of the circle. A curved matching portion 9033 is arranged on the end of the swinging ring plate 903, and the curvature of the curved matching portion 9033 is the same as that of the curved convex portion 9011 so that when the swinging ring plate 903 swings, the gap between the swinging ring plate 903 and the primary air duct 901 is always consistent. It can be understood here that the curved convex portion 9011 is a structure with high middle and low sides, and the overall cross-sectional shape is an arc, and the center of the arc is the center of the connecting shaft 9052. The arrangement here can ensure that the swinging ring plate 903 swings along the primary air duct 901, and at the same time, the gap between the two is minimized, thereby reducing heat energy loss.

[0072] See attached Fig.12 The air outlet of the swing ring plate 903 is provided with a constricted portion 9031 and an outward expansion portion 9032. The constricted portion 9031 is an end portion extending in a direction of reducing the diameter, and the outward expansion portion 9032 is an end portion extending in a direction of expanding the diameter. It can be understood here that the constricted portion 9031 is to reduce the diameter of the air outlet of the swing ring plate 903, and the outward expansion portion 9032 is to provide a guiding surface for outward expansion. However, the outward expansion portion 9032 protrudes from the constricted portion 9031 in the axial direction, and the constricted portion 9031 is to reduce the diameter of the air outlet of the swing ring plate 903. An end face extending radially is formed between the mouth portion 9031 and the outward expansion portion 9032. The area formed by the end face, the outward expansion portion 9032 and the necked portion 9031 is a recirculation zone. The angle between the outward expansion portion 9032 and the necked portion 9031 is an obtuse angle α, and the value range of the obtuse angle is: 90°<α<135°. This is beneficial for ensuring the nozzle wind speed while realizing partial supplement of the primary air to the recirculation zone, which is beneficial for improving the sufficiency of the primary air combustion and improving the combustion efficiency.

[0073] When the flame nozzle of the present invention is installed at the burner outlet, the swing power unit is fixedly installed relative to the primary air duct 901. When the flame ejection angle and direction need to be adjusted, the swing power unit drives the connecting rod, and the connecting rod drives the swing shaft 904 to move, thereby realizing the swing ring plate 903 to rotate along the connecting shaft 9052, thereby realizing the up and down swinging movement of the swing ring plate 903.

[0074] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A universal full-time ultra-low nitrogen burner, characterized in that: include: A combustion assembly (300), the combustion assembly (300) comprising a combustion cylinder (301) and an outer cylinder (302) sleeved on an outer layer thereof, the cavity formed between the combustion cylinder (301) and the outer cylinder (302) being connected to a return air cavity (303), a combustion chamber (305) being arranged in the combustion cylinder (301), and an inlet end of the combustion chamber (305) being respectively connected to a powder inlet (600), a plasma igniter and a purge assembly (400); The tempering nozzle (800) is arranged on the inner wall of the outlet end of the combustion chamber (305), and its air inlet is connected to the cavity between the combustion tube (301) and the outer tube (302), and its air outlet is connected to the combustion chamber (305) and is opposite to the powder feeding direction; A backfire passage (700) is arranged on the inner wall of the combustion chamber (305) between the backfire air outlet (8011) of the backfire nozzle (800) and the purge air outlet (501) of the purge assembly (400), and the backfire passage (700) is a structure with openings at both ends connected to the combustion chamber (305), and is used to provide a passage for the backflow air blown out by the backfire nozzle (800) to entrain the flame in the combustion chamber (305) and then circulate toward the inlet end of the combustion chamber (305).

2. A universal full-time ultra-low nitrogen burner according to claim 1, characterized in that: The tempering air outlet (8011) of the tempering nozzle (800), the tempering channel (700) and the purge air outlet (501) of the purge assembly (400) are all located in the upper half of the combustion chamber (305); the cross section of the tempering channel (700) accounts for 1 / 5 to 1 / 2 of the cross section area of ​​the combustion chamber (305); the outlet of the plasma igniter is located in the lower half of the combustion chamber (305); and the powder inlet (600) is located at the bottom of the combustion chamber (305).

3. A universal full-time ultra-low nitrogen burner according to claim 2, characterized in that: A slit opening (702) is provided at the bottom of the tempering channel (700), and the slit opening (702) is used to connect the tempering channel (700) and the combustion chamber (305). A cooling cavity (701) is provided inside the tempering channel (700), and an inlet of the cooling cavity (701) is connected to the cavity between the combustion tube (301) and the outer tube (302), and an outlet of the cooling cavity (701) is connected to the combustion chamber (305).

4. A universal full-time ultra-low nitrogen burner according to claim 3, characterized in that: The purge assembly (400) comprises a purge air inlet pipe (402) and a buffer air chamber (403); one end of the buffer air chamber (403) is connected to the purge air inlet pipe (402); and a guide block (500) is installed at the other end; a channel is arranged inside the guide block (500); one end of the channel is connected to the buffer air chamber (403); and the other end of the channel is connected to the combustion chamber (305) through a purge air outlet (501); the guide block (500) is used to provide guidance for the circulating flame flowing out of the outlet of the backfire channel (700).

5. A universal full-time ultra-low nitrogen burner according to claim 4, characterized in that: An end seat (304) for sealing the inlet end of the outer cylinder (302) is provided at the inlet end of the outer cylinder (302); the purge air inlet pipe (402) of the purge assembly (400) and the plasma generator bracket (100) both pass through the end seat (304); a plasma igniter whose outlet is connected to the combustion chamber (305) is installed in the plasma generator bracket (100); the buffer air cavity (403) is located in the return air cavity (303) surrounded by the end cover, the combustion cylinder (301) and the outer cylinder (302); an air chamber (200) is provided on the outer side wall of the end seat (304); the air chamber (200) is provided with an air inlet hole (201) connected to an external air source; and the air chamber (200) is connected to the return air cavity (303) and the inlet of the purge air inlet pipe (402).

6. A universal full-time ultra-low nitrogen burner according to claim 5, characterized in that: The surface of the guide block (500) facing the combustion chamber (305) is configured as a concave arc surface, and the arc surface is used to form a smooth transition between the inner wall of the combustion cylinder (301) and the outlet of the plasma generator bracket (100).

7. A universal full-time ultra-low nitrogen burner according to claim 6, characterized in that: The burner has a flame outlet (900) installed thereon, comprising: A primary air duct (901), one end of which is in communication with the furnace of the burner and is used to discharge primary air; A swing ring plate (903) is mounted on the air outlet of the primary air duct (901) and is swingably mounted relative to the primary air duct (901); The secondary air duct (902) is sleeved on the outside of the swing ring plate (903) and fixedly installed relative to the swing ring plate (903), and a cavity is formed between the secondary air duct (902) and the swing ring plate (903) for discharging secondary air; The swing shaft (904) is fixedly mounted relative to the swing ring plate (903) and is mounted at the power end of the swing power unit, and the swing power unit is used to drive the swing ring plate (903) to swing relative to the primary air duct (901).

8. A universal full-time ultra-low nitrogen burner according to claim 7, characterized in that: A connecting shaft (9052) is provided in the middle of the side of the swing ring plate (903), a connecting block (905) is provided at a corresponding position of the primary air duct (901), the connecting shaft (9052) is rotatably mounted on the connecting block (905), and the swing shaft (904) is provided on the upper side or the lower side of the connecting shaft (9052).

9. A universal full-time ultra-low nitrogen burner according to claim 8, characterized in that: A curved convex portion (9011) is arranged on the outside of the primary air duct (901), the curved convex portion (9011) having the center of the connecting shaft (9052) as its center. A curved matching portion (9033) is arranged on the end of the swing ring plate (903), the curved matching portion (9033) having the same curvature as the curved convex portion (9011) so that when the swing ring plate (903) swings, the gap between the swing ring plate (903) and the primary air duct (901) is always consistent.

10. A universal full-time ultra-low nitrogen burner according to claim 9, characterized in that: A constricted portion (9031) and an outwardly expanding portion (9032) are provided at the air outlet of the swing ring plate (903); the constricted portion (9031) is an end portion extending in a direction of reducing the diameter, and the outwardly expanding portion (9032) is an end portion extending in a direction of expanding the diameter; the outwardly expanding portion (9032) protrudes from the constricted portion (9031) in the axial direction; an end face extending in the radial direction is formed between the constricted portion (9031) and the outwardly expanding portion (9032); a region formed between the end face and the outwardly expanding portion (9032) and the constricted portion (9031) is a reflow region; an angle between the outwardly expanding portion (9032) and the constricted portion (9031) is an obtuse angle α, and the value range of the obtuse angle is: 90°<α<135°.

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