A burner

Abstract

The present invention discloses a burner, comprising a central tube, a swirl air duct, a coal air duct, an inner axial air duct and an outer axial air duct arranged together from the inside to the outside, the coal air duct is formed by rotating and splicing a short tube body at the front end and a long tube body at the rear end, a plurality of V-shaped air guide plates are arranged in an annular direction on the outer wall of the short tube body, the tip of the V-shaped air guide plate faces the long tube body, and the open end faces the burner outlet, and the two plates constituting the V-shaped air guide plate are respectively expanded outward in concave arcs on both sides, and a plurality of isolation plates are arranged in the axial direction on the outer wall of the long tube body, and a plurality of isolation air ducts in the axial direction are isolated by the isolation plates, and the front end of each isolation air duct faces the tip of a V-shaped air guide plate respectively. The burner can fully mix the ejected airflow, and can fully change the flame shape by changing the ejection state of high-speed wind, so that the coal powder can be fully burned under different process conditions and coal quality.

Description

Technical Field

[0001] The invention relates to the field of rotary kiln burners, and in particular to a burner. Background Art

[0002] The burner is used as an ejector in the rotary kiln of cement production. High-speed wind and coal powder are ejected from the burner at the same time and burn at the burner outlet to produce a high-temperature flame. Most of the initial burners were simple single-duct or double-duct coal powder burners. Most of these burners have long black flames and low combustion efficiency. In the 1980s and 1990s, three-duct and four-duct burners were developed successively, which greatly improved the combustion efficiency. However, there are still problems such as unstable air supply and the inability to adjust the flame shape and temperature. When the production environment and process conditions change, or the coal quality changes, the flame shape cannot be adjusted accordingly, resulting in the inability of coal powder to burn completely. Some existing burners are equipped with an axial moving device on the pipeline. The axial movement of the pipeline can change the angle of high-speed wind ejection, thereby realizing the change of the flame shape. However, since the range of axial movement of the pipeline is limited, the degree of flame change is not ideal, and there is still the problem of insufficient combustion of coal powder. Summary of the invention

[0003] The purpose of the present invention is to propose a new burner to address the problem that the flame shape of existing burners is difficult to change. The burner guides the angle and air volume of high-speed air ejected from the burner by arranging an isolation air duct and a V-shaped air guide plate. When the high-speed air is ejected, it can perform vortex-like collision from cross directions to make the airflow mixing more uniform. When the angles of the isolation air duct and the V-shaped air guide plate are changed, the air volume of the high-speed air ejected from different angles can be changed, thereby changing the airflow state after the cross-collision, and then fully changing the flame shape to adapt to changes in process conditions or coal quality and make the coal powder burn more fully.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a burner, comprising a central tube, a swirl air duct, a coal air duct, an inner axial flow air duct and an outer axial flow air duct arranged together from the inside to the outside, a swirler is provided at the front end of the swirl air duct, a plurality of inclined swirl air branches are provided on the swirler, and the inclination angle of the swirl air branches is 20-50°, a telescopic joint is provided at the rear end of the swirl air duct for driving the swirl air duct to expand and contract in the axial direction, the coal air duct is formed by rotating and splicing a short tube body at the front end and a long tube body at the rear end, a plurality of V-shaped air guide plates are evenly provided on the outer wall of the short tube body along the circumferential direction, and the The tip of the V-shaped air guide plate faces the long tube body, and the open end faces the burner outlet. The two plates constituting the V-shaped air guide plate expand outward in concave arcs on both sides. The short tube body, the V-shaped air guide plate and the inner axial flow air duct are fixed as a whole. The long tube body is provided with a plurality of isolation plates along the circumferential direction on the outer wall of one end facing the short tube body. The isolation plates are rectangular plates, which are fixed in a state perpendicular to the tube wall of the long tube body along the axial direction. The isolation plates isolate a plurality of isolation air ducts between the long tube body and the inner axial flow air duct, and the front end outlet of each isolation air duct faces the tip of the V-shaped air guide plate.

[0005] According to one embodiment of the present invention, for the burner, an oil gun channel is formed in the central tube, a swirl air duct is formed between the central tube and the swirl air duct, a coal air channel is formed between the swirl air duct and the coal air duct, an inner axial flow air duct is formed between the coal air duct and the inner axial flow air duct, and an outer axial flow air duct is formed between the inner axial flow air duct and the outer axial flow air duct.

[0006] According to one embodiment of the present invention, for the burner, the outside of the burner is provided with an inner wind inlet, a coal wind inlet and an outer wind inlet which lead into the swirl air duct, the coal wind channel and the inner axial flow air duct respectively, and the inner axial flow air duct is provided with a diversion port which diverts the inner axial flow wind into the outer axial flow air duct.

[0007] According to an embodiment of the present invention, for the burner, the height of the isolation plate is the same as the distance between the coal air duct and the inner axial flow air duct.

[0008] According to an embodiment of the present invention, for the burner, the angle between the two plates constituting the V-shaped air guide plate and the rear end ring opening of the short tube body is 60-75°.

[0009] According to an embodiment of the present invention, the burner is characterized in that a flame retardant portion cast from a high temperature resistant material is provided on the outer periphery of the front end of the outer axial flow air duct.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] The burner provided by the present invention guides the angle and air volume of high-speed wind ejected from the burner by arranging an isolation air duct and a V-shaped air guide plate. When the high-speed wind reaches the tip of the V-shaped air guide plate from the isolation air duct, it is diverted by the V-shaped air guide plate, so that the high-speed wind is divided into two streams, which are ejected from the burner outlet in a forward and reverse rotation state from both sides of the V-shaped air guide plate respectively. The high-speed wind ejected from the opening formed between two adjacent V-shaped air guide plates is vortex-type counter-attacked in a cross manner, so that the airflow is mixed more evenly, and after the long tube body at the rear end of the coal air duct is rotated, the orientation angle of the isolation air duct and the V-shaped air guide plate is changed, which can change the air volume of the high-speed wind ejected from the forward and reverse rotation directions, thereby changing the airflow state after the cross-counterattack, and then fully changing the flame shape to adapt to changes in process conditions or coal quality, so that the coal powder burns more fully. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the present invention;

[0013] Figure 2 It is a schematic diagram of the structure of each pipeline and air duct in the present invention;

[0014] Figure 3 It is a front view of the coal air duct and the inner axial flow air duct in the present invention;

[0015] Figure 4 It is a schematic diagram of the state change of the positive and negative cyclonic air volume before and after the long tube body rotates in the present invention;

[0016] Figure 5 It is a schematic diagram of the structure of the cyclone at the front end of the cyclone air duct before adjustment in the present invention;

[0017] Figure 6 It is a schematic diagram of the structure of the cyclone at the front end of the cyclone air duct after adjustment in the present invention;

[0018] Figure 7 is a schematic diagram of the front end surface of the present invention; DETAILED DESCRIPTION

[0019] 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.

[0020] See also Figure 1-7 The present invention provides a technical solution: a burner, comprising: Figure 1The central tube 1, the swirl air duct 2, the coal air duct 3, the inner axial air duct 4 and the outer axial air duct 5 are arranged together from the inside to the outside. The front end of the swirl air duct 2 is provided with a swirler 21, and the swirler 21 is provided with a plurality of inclined swirl air branches 22. The inclination angle of the swirl air branch 22 is 20-50°. The rear end of the swirl air duct is provided with a telescopic joint for driving the swirl air duct to expand and contract in the axial direction. The coal air duct 3 is formed by rotating and splicing a short tube body 19 at the front end and a long tube body 20 at the rear end. A plurality of V-shaped air guide plates 6 are evenly arranged on the outer wall of the short tube body 19 along the circumferential direction. The tip of the V-shaped air guide plate 6 faces the The long tube body 20 has an open end facing the burner outlet, and the two plates constituting the V-shaped air guide plate 6 expand outward in concave arcs on both sides. The short tube body 19, the V-shaped air guide plate 6 and the inner axial flow air duct 4 are fixed as a whole. The long tube body 20 is provided with a plurality of isolation plates 7 along the annular direction on the outer wall of the end facing the short tube body 19. The isolation plates 7 are rectangular plates, which are fixed in a state perpendicular to the tube wall of the long tube body 20 along the axial direction. The isolation plates 7 isolate a plurality of isolation air ducts 8 between the long tube body 20 and the inner axial flow air duct 4, and the front end outlet of each of the isolation air ducts 8 faces the tip of one of the V-shaped air guide plates 6.

[0021] like Figure 3 As shown, the tip of the V-shaped air guide plate 6 faces the rear end of the burner, and the open end faces the burner outlet, and the V-shaped air guide plate 6, the short tube body 19 and the inner axial flow air duct 4 are fixed as a whole, and a plurality of high-speed air outlets are separated at the front end of the coal air duct 3 and the inner axial flow air duct 4 by the V-shaped air guide plate 6, and each high-speed air outlet is located between two adjacent V-shaped air guide plates 6; the long tube body 20 at the rear end of the coal air duct 3 and the short tube body 19 at the front end are rotatably connected, so the long tube body 20 can rotate freely.

[0022] There is an annular high-speed air duct between the coal air duct 3 and the inner axial flow air duct 4. Figure 4As shown, a plurality of axially isolated air ducts 8 are isolated by a plurality of isolation plates 7 axially arranged on the outer wall of the long tube body 20, and the front end of each isolation air duct 8 faces the tip of a V-shaped air guide plate 6 respectively. The high-speed wind advances in the high-speed air duct between the coal air duct 3 and the inner axial flow air duct 4. When it reaches the isolation plate 7, the high-speed wind enters each of the isolation air ducts 8 respectively, and continues to advance in the isolation air duct 8 until it is ejected from the front end opening of the isolation air duct 8, and the tip of the V-shaped air guide plate 6 faces the front end opening of the isolation air duct 8, so the ejected high-speed wind is divided into two by the V-shaped air guide plate 6, one of which is ejected from the burner outlet in a positive rotation direction along the plate body on one side of the V-shaped air guide plate 6, and the other is ejected from the burner outlet along the V-shaped air guide plate 6. The plate body on the other side of plate 6 is ejected from the burner outlet in a counter-rotating direction. In this case, both positive cyclone and counter-cyclone are ejected from the same high-speed air outlet between the two adjacent V-shaped air guide plates 6, and the two winds are vortex-like collided in a cross manner, so that the airflow can be fully mixed and evenly mixed, and when the long tube body 20 at the rear end of the coal air pipe 3 is rotated, the angle of the isolation air duct 8 changes, and the direction angle of the isolation air duct 8 toward the tip of the V-shaped air guide plate 6 can be changed. In this case, the air volume of the positive cyclone and the counter-cyclone that are diverted will also change, so that the positive cyclone and the counter-cyclone will present different injection states after the cross-collision, and then the shape of the flame can be fully changed to adapt to the changes in process conditions or coal quality, so that the coal powder can be burned more fully.

[0023] like Figure 5 and 6 As shown, a swirler 21 is provided at the front end of the swirl air duct 10, and a plurality of inclined swirl wind branches 22 are provided on the swirler 21. The high-speed wind in the swirl air duct 10 is sent to the swirler 21, enters each swirl wind branch duct 22, and finally is ejected from the burner outlet in a swirl state. The swirler 21 is fixed on the front end of the central tube 1, and a telescopic joint is provided at the rear end of the central tube 1, through which the central tube 1 can be driven to telescope in the axial direction. Figure 5 The state of the central tube 1 before the telescopic adjustment is shown. Figure 6 The state of the central tube 1 after the telescopic adjustment is shown. Figure 5 Hehe Figure 6 From the comparison, it can be seen that the angle of high-speed wind ejected from the burner outlet from the swirl wind branch channel has changed before and after adjustment. By changing the angle of swirl wind ejection, the shape of the flame at the burner outlet can also be adjusted.

[0024] In another embodiment, for the burner, an oil gun channel 9 is formed in the central tube 1, a cyclone air duct 10 is formed between the central tube 1 and the cyclone air duct 2, a coal air channel 11 is formed between the cyclone air duct 2 and the coal air duct 3, an inner axial air duct 12 is formed between the coal air duct 3 and the inner axial air duct 4, and an outer axial air duct 13 is formed between the inner axial air duct 4 and the outer axial air duct 5. The structures of the pipes and air ducts are as follows: Figure 2 shown.

[0025] In another embodiment, for the burner, the outside of the burner is provided with an inner wind inlet 14, a coal wind inlet 15 and an outer wind inlet 16 which respectively lead into the swirl air duct 10, the coal wind channel 11 and the inner axial flow air duct 12, and the inner axial flow air duct 4 is provided with a diversion port for introducing the inner axial flow wind into the outer axial flow air duct 13.

[0026] In another embodiment, for the burner, the height of the isolation plate 7 is the same as the distance between the coal air duct 3 and the inner axial flow air duct 4, so as to achieve full isolation of each isolation air duct 8.

[0027] According to one embodiment of the present invention, for the burner, the angle between the two plates constituting the V-shaped air guide plate 6 and the rear end ring opening of the short tube body 19 is 60-75°. The angle cannot be too large or too small. If the angle is too small, it will affect the ejection speed of the high-speed wind. If the angle is too small, the positive cyclone and the reverse cyclone ejected from the same high-speed wind outlet cannot achieve sufficient cross-offensive.

[0028] In another embodiment, for the burner, the outer periphery of the front end of the outer axial flow air duct 5 is provided with a flame retardant portion 18 cast from a high temperature resistant material.

[0029] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A burner, characterized in that: The invention comprises a central tube, a swirl air duct, a coal air duct, an inner axial air duct and an outer axial air duct which are arranged together from the inside to the outside. A swirler is arranged at the front end of the swirl air duct. The swirler is provided with a plurality of inclined swirl air branches. The inclination angle of the swirl air branches is 20-50°. A telescopic joint is arranged at the rear end of the swirl air duct to drive the swirl air duct to expand and contract in the axial direction. The coal air duct is formed by rotating and splicing a short tube body at the front end and a long tube body at the rear end. A plurality of V-shaped air guide plates are evenly arranged on the outer wall of the short tube body along the circumferential direction. The tip of the V-shaped air guide plate faces the long tube body, and the open end faces the burner outlet. The two plates constituting the V-shaped air guide plate are respectively on both sides. It expands outward in a concave arc, and the short tube body, V-shaped air guide plate and inner axial flow air duct are fixed as a whole. The long tube body is provided with a plurality of isolation plates along the annular direction on the outer wall of one end facing the short tube body. The isolation plates are rectangular plates, which are fixed in a vertical state to the tube wall of the long tube body along the axial direction. The isolation plates isolate a plurality of isolation air ducts between the long tube body and the inner axial flow air duct, and the front end outlet of each isolation air duct faces the tip of one of the V-shaped air guide plates; the height of the isolation plate is the same as the distance between the coal air duct and the inner axial flow air duct; the angle between the two plates constituting the V-shaped air guide plate and the rear end ring opening of the short tube body is 60-75°.

2. The burner according to claim 1, characterized in that An oil gun channel is formed in the central tube, a cyclone air duct is formed between the central tube and the cyclone air duct, a coal air channel is formed between the cyclone air duct and the coal air duct, an inner axial flow air duct is formed between the coal air duct and the inner axial flow air duct, and an outer axial flow air duct is formed between the inner axial flow air duct and the outer axial flow air duct.

3. The burner according to claim 2, characterized in that: The burner is provided with an inner wind inlet, a coal wind inlet and an outer wind inlet respectively leading to the swirl air duct, the coal wind channel and the inner axial flow air duct. The inner axial flow air duct is provided with a diversion port for diverting the inner axial flow air into the outer axial flow air duct.

4. The burner according to claim 1, characterized in that The outer periphery of the front end of the outer axial flow air duct is provided with a flame retardant portion cast by high temperature resistant material.

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