Tempering nozzle with air heating function and combustor

Abstract

The utility model provides a tempering nozzle with an air heating function and a combustor, and relates to the technical field of pulverized coal combustion equipment. The outer cylinder is coaxially arranged on the outer side of the inner cylinder in a sleeving mode, an air inlet cavity is formed between the inner cylinder and the outer cylinder, an air inlet hole communicated with the air inlet cavity is formed in the outer cylinder, one end of the outer cylinder is connected with an air return part, and the other end of the outer cylinder is connected with the inner cylinder through an air injection part; the air return part penetrates through the air inlet cavity and an inner cavity of the inner cylinder; and the air injection part penetrates through the inner cavity of the inner barrel, and the injection direction of the air injection part deviates from the air return part, so that the technical problem that the stable combustion performance is influenced by lower temperature of normal-temperature compressed air is solved, the heat exchange area and the temperature of the compressed air are increased, and a better stable combustion effect is achieved.

Description

Technical Field

[0001] This utility model relates to a tempering nozzle and burner with air heating, belonging to the technical field of pulverized coal combustion equipment. Background Technology

[0002] Currently, the installation of flame extraction devices in burners greatly improves the stable combustion of pulverized coal in boilers under low-load operation. However, conventional flame extraction devices often use ambient temperature compressed air as the power source. The inventors have found that conventional flame extraction devices cannot effectively achieve stable combustion of pulverized coal. On the contrary, the compressed air used in the flashback device has a higher temperature, which is more conducive to stable combustion of pulverized coal. In other words, the temperature of the compressed air has a greater impact on ignition. In addition, the compressed air in the traditional flame extraction device is ejected from inside the flame extraction tube, and there are pulverized coal flames both inside and outside the flame extraction tube, which poses a significant safety hazard. Utility Model Content

[0003] This utility model addresses the shortcomings of existing technologies by providing a tempering nozzle with air heating, comprising:

[0004] Inner cylinder; outer cylinder, the outer cylinder being coaxially sleeved on the outside of the inner cylinder, an air intake cavity being formed between the inner cylinder and the outer cylinder, the outer cylinder having an air intake hole communicating with the air intake cavity, one end of the outer cylinder being connected to a return air section, and the other end being connected to the inner cylinder through a jet air section; the return air section communicating with the inner cavity of the air intake cavity and the inner cylinder; the jet air section communicating with the inner cavity of the inner cylinder and the jet air section being sprayed in a direction opposite to the return air section.

[0005] Furthermore, the jet unit includes a nozzle and a nozzle pipe. One end of the nozzle pipe connects the inner cylinder to the outer cylinder, and the other end is tapered and connected to the nozzle at the tapered position. The nozzle is a circular tube, and the tube wall of the circular tube is provided with several air outlet holes. The inner hole of the circular tube and each air outlet hole are in communication with the inner cavity of the inner cylinder and parallel to the axis of the circular tube. The diameter of the air outlet hole is smaller than the inner diameter of the circular tube.

[0006] Furthermore, the nozzle constriction position is provided with a plurality of air jets, which are connected to the inner cavity of the inner cylinder and are parallel to the nozzle axis.

[0007] Furthermore, the air inlet is located at the end away from the tempering section.

[0008] Furthermore, the tempering section is provided with a cooling hole at its central axis and / or on the outer cylinder that communicates with the air intake cavity.

[0009] In another aspect, this utility model also provides a burner, which includes any of the above-mentioned flashback nozzles; it also includes an extraction tube, the extraction side of which has a funnel-shaped opening, and the nozzle of the jet unit facing the extraction side of the extraction tube; a flashback shield, which is disposed at the outlet of the extraction tube; an igniter, the ignition position of which is located on the side of the flashback shield away from the extraction tube; and a combustion chamber, in which the extraction tube, the flashback nozzle, the flashback shield, and the igniter are all fixed inside the combustion chamber and are all coaxially arranged with the combustion chamber.

[0010] Furthermore, the tempering shield is a cone, and the bottom surface of the cone has a groove that is the same as the axis of the cone, with the groove facing the exhaust pipe.

[0011] The beneficial effects of this utility model include:

[0012] (1) After compressed air enters the intake chamber through the intake port, it enters the jet section through the return section and is ejected by the nozzle; the arrangement of the outer cylinder and the inner cylinder provides a large heat exchange area, and the temperature of the compressed air ejected by the regenerating nozzle in the combustion chamber can be effectively increased.

[0013] (2) The compressed air ejected from this flashover nozzle has a higher temperature, which is more conducive to the stable combustion of pulverized coal and has a better stable combustion effect;

[0014] (3) In traditional fire extraction devices, compressed air is sprayed out from inside the fire extraction pipe, and there are coal powder flames inside and outside the fire extraction pipe, which poses a significant safety hazard. The compressed air chamber of the backfire nozzle provided by this utility model has no flame combustion inside, which improves the safety performance of the device. Attached Figure Description

[0015] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of the tempering nozzle provided in an embodiment of the present invention;

[0017] Figure 2 This is a schematic diagram of the burner provided in an embodiment of the present invention.

[0018] Reference numerals: 1. Inner cylinder; 2. Outer cylinder; 21. Air inlet; 3. Air inlet chamber; 4. Jet jet; 41. Nozzle; 412. Jet nozzle; 42. Nozzle head; 422. Air outlet; 5. Return gas section; 51. Cooling hole; 6. Exhaust pipe; 7. Tempering shield; 71. Groove; 8. Ignition device; 9. Combustion tube. Detailed Implementation

[0019] The specific embodiments of this utility model are described in detail below. This utility model can be implemented in many ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed herein.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used is for describing particular embodiments only and is not intended to limit the scope of this invention.

[0021] This invention provides a tempering nozzle with air heating, such as... Figure 1 As shown, it includes: an inner cylinder 1; an outer cylinder 2, the outer cylinder 2 being coaxially sleeved on the outside of the inner cylinder 1, an air intake cavity 3 being formed between the inner cylinder 1 and the outer cylinder 2, the outer cylinder 2 being provided with an air intake hole 21 communicating with the air intake cavity 3, one end of the outer cylinder 2 being connected to a return air section 5, and the other end being connected to the inner cylinder 1 through a jet air section 4; the return air section 5 communicating with the inner cavity of the air intake cavity 3 and the inner cavity of the inner cylinder 1; the jet air section 4 communicating with the inner cavity of the inner cylinder 1 and the jet direction of the jet air section 4 being opposite to the return air section 5.

[0022] This embodiment provides a tempering nozzle with air heating. Compressed air enters the air inlet chamber 3 through the air inlet 21, then enters the jet section 4 through the return air section 5, and is ejected by the nozzle 42. The arrangement of the outer cylinder 2 and the inner cylinder 1 provides a large heat exchange area, which can effectively increase the temperature of the compressed air ejected from the tempering nozzle. The high temperature of the compressed air ejected from this tempering nozzle is more conducive to the stable combustion of pulverized coal. There is no flame combustion inside the compressed air chamber of this device, which improves the safety performance of the device.

[0023] Specifically, the jet unit 4 includes a nozzle 42 and a nozzle pipe 41. One end of the nozzle pipe 41 connects the inner cylinder 1 and the outer cylinder 2, and the other end is constricted and connected to the nozzle 42 at the constricted position. The nozzle 42 is a circular tube, and the tube wall of the circular tube is provided with a plurality of air outlet holes 422. The inner hole of the circular tube and each of the air outlet holes 422 are connected to the inner cavity of the inner cylinder 1 and are parallel to the axis of the circular tube. The diameter of the air outlet hole 422 is smaller than the inner diameter of the circular tube.

[0024] This embodiment provides a specific structure of the jet nozzle 42. A conventional nozzle 42 has only one jet hole, resulting in low jet efficiency. The nozzle 42 provided in this embodiment achieves a jet efficiency that is much higher than that of a conventional nozzle 42 by setting an exhaust hole 422.

[0025] Specifically, the nozzle 41 is provided with a plurality of air jets 412 at the constriction position, and the air jets 412 are in communication with the inner cavity of the inner cylinder 1 and are parallel to the axis of the nozzle 41.

[0026] The jet nozzles of nozzle 41 form a two-stage jet, further improving the jetting efficiency, and the ejected compressed air forms a vortex with the oncoming coal dust. Preferably, the jet nozzles 412 are evenly arranged around the nozzle 42, and each jet nozzle 412 is at the same distance from the nozzle 42.

[0027] Specifically, the air inlet 21 is located at the end away from the tempering section.

[0028] The farther the air inlet 21 is from the tempering section, the longer it takes for the compressed air to reach the tempering section, all other things being equal, which is more beneficial for the heat exchange of the compressed air. Placing the air inlet 21 at the end furthest from the tempering section is more conducive to increasing the heat exchange area and heat exchange efficiency.

[0029] Specifically, the tempering section is provided with a cooling hole 51 at the center axis position and / or on the outer cylinder 2, which communicates with the air intake cavity 3.

[0030] The regenerating nozzle is placed in the flame for a long time, which causes the temperature of the outer cylinder 2 and the return air section 5 to remain high for a long time, which can easily damage the regenerating nozzle. The setting of the cooling hole 51 can accelerate the flow speed of compressed air in the air inlet chamber 3 and the return air section 5, which has the effect of ventilation and cooling for the regenerating nozzle, especially the outer cylinder 2 and the return air section 5.

[0031] In another aspect, this utility model also provides a burner, which includes the flashback nozzle described in any of the above claims; it also includes an extraction pipe 6, the extraction side of which has a funnel-shaped opening, and the nozzle 42 of the jet section 4 facing the extraction side of the extraction pipe 6; a flashback shield 7, which is disposed at the outlet of the extraction pipe 6; an igniter 8, the ignition position of which is located on the side of the flashback shield 7 away from the extraction pipe 6; and a combustion cylinder 9, in which the extraction pipe 6, the flashback nozzle, the flashback shield 7, and the igniter 8 are all fixed inside the combustion cylinder 9 and are all coaxially arranged with the combustion cylinder 9.

[0032] During the ignition phase, the igniter 8 ignites the continuously entering pulverized coal in the combustion chamber. When the flame passes the flashback shield 7 and the outside of the extraction pipe 6 to reach the extraction side of the extraction pipe 6, the compressed air rapidly ejected by the nozzle 42 forms a relative negative pressure at the inlet of the extraction side of the extraction pipe 6. The compressed air and the pulverized coal flame at the inlet of the extraction pipe 6 form a vortex. The flame and flame vortex around the extraction side inlet of the extraction end are drawn into the extraction pipe 6, and the flame follows the compressed air to the space between the extraction pipe 6 and the flashback shield 7, igniting the continuously entering pulverized coal. After the flame here ignites the pulverized coal from the direction of the flashback shield 7, it follows the pulverized coal airflow to the combustion boiler. After a period of time, more and more flames are drawn between the extraction pipe 6 and the backfire shield 7, which can ignite more coal powder. When the drawn flame can stably ignite the continuously entering coal powder, the ignition of the igniter 8 is stopped. In addition, the extraction side of the extraction pipe 6 is set as a funnel-shaped opening, which can improve the extraction efficiency. The compressed air blown out of the air outlet 422 forms a vortex with the oncoming coal powder flame on the funnel-shaped opening side. The extraction pipe 6 can draw the coal powder flame vortex into the outlet pipe, further improving the extraction efficiency.

[0033] Furthermore, the tempering shield 7 is a cone, and the bottom surface of the cone is provided with a groove 71 that is the same as the axis of the cone, and the groove 71 faces the exhaust pipe 6.

[0034] The conical shape of the tempering shield 7 facilitates the dispersion of incoming pulverized coal. The groove 71 allows the flame drawn back by the exhaust pipe 6 to better ignite the incoming pulverized coal, which then follows the pulverized coal airflow into the combustion furnace, forming a better extraction and circulation. Preferably, the tempering shield 7 has a compressed air cavity structure, with a through hole on the axial side of the tempering shield 7 facing the igniter 8. The compressed air injected from the through hole provides some protection to the tempering shield 7, reducing wear from the pulverized coal.

[0035] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are exhaustively listed. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0036] For those skilled in the art, various modifications and improvements can be made without departing from the concept of this utility model, and these modifications and improvements are all within the protection scope of this utility model. The protection scope of this utility model is defined by the appended claims.

Claims

1. A tempering nozzle with air heating, characterized in that, include: Inner cylinder; An outer cylinder is coaxially sleeved on the outside of the inner cylinder, and an air intake cavity is formed between the inner cylinder and the outer cylinder. An air intake hole communicating with the air intake cavity is provided on the outer cylinder. One end of the outer cylinder is connected to the air return section, and the other end is connected to the inner cylinder through the air jet section. The return air section connects the air intake cavity and the inner cavity of the inner cylinder; The jet nozzle penetrates the inner cavity of the inner cylinder, and the jet direction of the jet nozzle is opposite to that of the return air nozzle.

2. The tempering nozzle according to claim 1, characterized in that, The jet unit includes a nozzle and a nozzle pipe. One end of the nozzle pipe connects the inner cylinder to the outer cylinder, and the other end is tapered and connected to the nozzle at the tapered position. The nozzle is a circular tube, and the tube wall of the circular tube is provided with several air outlet holes. The inner hole of the circular tube and each air outlet hole are connected to the inner cavity of the inner cylinder and are parallel to the axis of the circular tube. The diameter of the air outlet hole is smaller than the inner diameter of the circular tube.

3. The tempering nozzle according to claim 2, characterized in that, The nozzle has several air jets at its constriction position, and the air jets are connected to the inner cavity of the inner cylinder and are parallel to the nozzle axis.

4. The tempering nozzle according to claim 1, characterized in that, The air inlet is located at the end furthest from the air return section.

5. The tempering nozzle according to claim 1, characterized in that, The return air section is provided with a cooling hole at its central axis and / or on the outer cylinder, which communicates with the air intake cavity.

6. A burner, characterized in that, The burner includes the flashback nozzle according to any one of claims 1-5; it also includes a flame extraction tube, wherein the flame extraction side of the flame extraction tube has a funnel-shaped opening, and the nozzle of the jet unit faces the flame extraction side of the flame extraction tube. A flashback shield is provided at the flame outlet of the exhaust pipe; An igniter, wherein the ignition position of the igniter is located on the side of the flashback shield away from the exhaust tube; The combustion chamber, the extraction pipe, the flashback nozzle, the flashback shield and the igniter are all fixed inside the combustion chamber and are all coaxially arranged with the combustion chamber.

7. The burner according to claim 6, characterized in that, The tempering shield is a cone, and the bottom surface of the cone has a groove that is the same as the axis of the cone, with the groove facing the exhaust pipe.

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