Pulverized coal stable combustion device

Abstract

The invention provides a pulverized coal stable combustion device which comprises a combustor and a combustion stabilizer, and at least part of the combustion stabilizer is located in the combustor. The combustion stabilizer comprises a housing, a backflow cylinder, an acceleration cylinder and a pulverized coal pipe assembly, the housing covers the outer side of the backflow cylinder, and a reinforcing layer is arranged between the housing and the backflow cylinder; the backflow cylinder and the acceleration cylinder are connected to define a stable combustion cavity, the pulverized coal pipe assembly is provided with a pulverized coal feeding port, and the pulverized coal feeding port is formed in the stable combustion cavity so as to convey pulverized coal fluid into the stable combustion cavity. According to the pulverized coal stable combustion device, the structural strength and durability of equipment are effectively enhanced, the combustion efficiency and stability of pulverized coal are greatly improved, and a brand new solution and technical breakthrough are brought to the field of industrial combustion.

Description

Technical Field

[0001] The invention relates to the technical field of coal powder combustion, and in particular to a coal powder combustion stabilizing device. Background Art

[0002] As one of the key equipment in thermal power plants and other industrial furnaces, the operating performance of pulverized coal combustion equipment directly affects the energy efficiency and safety of the entire system. However, during the use of pulverized coal combustion equipment, the stabilizer is in the high-temperature combustion chamber of the burner for a long time, which is prone to high-temperature wear, affecting the structural strength of the stabilizer, and thus reducing the service life of the stabilizer. Summary of the invention

[0003] The present invention is based on the inventor's discovery and understanding of the following facts and problems:

[0004] As a key component of pulverized coal combustion equipment, the flame stabilizer is designed to stabilize the flame and ensure that the pulverized coal burns evenly and efficiently in the combustion chamber. It is usually directly exposed to the high-temperature combustion chamber of the burner, and is subjected to extremely high temperatures and complex thermal stress environments. Under such extreme conditions, the flame stabilizer material is very susceptible to high-temperature oxidation, thermal fatigue, and mechanical wear, which not only weakens the structural strength of the flame stabilizer, but may also cause its shape to change, thereby affecting the stability of the flame and the combustion efficiency.

[0005] In the long run, high-temperature wear will seriously shorten the service life of the flame stabilizer, increase the frequency and cost of equipment maintenance, and may even cause unstable combustion, flameout or more serious safety accidents due to failure of the flame stabilizer, posing a threat to the stable operation of the entire system.

[0006] To this end, an embodiment of the present invention proposes a coal powder combustion stabilization device, which includes a burner and a flame stabilizer, at least part of which is located in the burner; the flame stabilizer includes a cover shell, a reflux cylinder, an acceleration cylinder and a coal powder pipe assembly, the cover shell is arranged on the outside of the reflux cylinder, and a reinforcement layer is provided between the cover shell and the reflux cylinder; the reflux cylinder and the acceleration cylinder are connected to define a combustion stabilization chamber, and the coal powder pipe assembly has a powder delivery port, which is arranged in the combustion stabilization chamber to transport the coal powder fluid into the combustion stabilization chamber.

[0007] In summary, the pulverized coal combustion stabilization device in the embodiment of the present invention not only effectively enhances the structural strength and durability of the equipment, but also greatly improves the combustion efficiency and stability of the pulverized coal, bringing new solutions and technological breakthroughs to the field of industrial combustion.

[0008] In some embodiments, the acceleration cylinder has a first end and a second end that are relatively set, the diameter of the first end is smaller than the diameter of the second end, and the first end is provided with a jet port; the reflux cylinder has a third end and a fourth end that are relatively set, the diameter of the third end is larger than the diameter of the fourth end, and the third end of the reflux cylinder is connected to the second end of the acceleration cylinder.

[0009] In some embodiments, the outer side of the housing is provided with a wear-resistant coating;

[0010] And / or, the reinforcement layer is made of thermal insulation cotton.

[0011] In some embodiments, the pulverized coal pipe assembly includes a first reflow channel and a second reflow channel, and the powder delivery port includes a first reflow port located in the first reflow channel and a second reflow port located in the second reflow channel, the first reflow port and the second reflow port are connected, the opening of the first reflow port and the opening of the second reflow port are both set toward the inner wall of the reflow cylinder, and the straight line where the opening direction of the first reflow port is located and the straight line where the opening direction of the second reflow port is located intersect, so as to spray the pulverized coal fluid into the stable combustion chamber.

[0012] In some embodiments, the pulverized coal pipe assembly includes a reflux cap and a guide plate, the first reflux channel and the second reflux channel are coaxially arranged in the reflux cap, the first reflux channel is located on the outside of the second reflux channel, the guide plate is arranged at the connection point between the first reflux port and the second reflux port, and the guide plate is provided with an inclined surface on the side facing the second reflux channel.

[0013] In some embodiments, the pulverized coal pipe assembly includes a supply pipe, in which a first channel and a second channel are provided, the first channel is connected to the first return channel, the second channel is connected to the second return channel, and the first channel and the second channel are used to transport different types of pulverized coal fluids into the combustion stabilization chamber.

[0014] In some embodiments, a secondary air component is also included, and the secondary air component includes a plurality of independent air ducts, and the air ducts have air supply ports, and the air supply ports are arranged at one end of the reflux tube, and the powder delivery ports are arranged at the other end of the reflux tube, and the air supply ports are staggered relative to the powder delivery ports in the radial direction of the combustion stabilization chamber.

[0015] In some embodiments, the secondary air component further includes a plurality of regulating valves, and the plurality of regulating valves are disposed one by one on the air duct, and the regulating valves are used to adjust the flow rate of the air flow in the air duct.

[0016] In some embodiments, the secondary air assembly further includes a plurality of rotor vanes, each of which is disposed at an air supply port of the air duct, and the rotor vanes are used to guide the airflow transported by the air duct to form a rotating airflow in the combustion stabilization chamber.

[0017] In some embodiments, the air duct and the pulverized coal pipe assembly are coaxially arranged, the air duct is arranged on the outside of the pulverized coal pipe assembly, and an annular blunt body is arranged between the air duct and the pulverized coal pipe assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a front schematic diagram of a pulverized coal combustion stabilizing device provided in an embodiment of the present invention.

[0019] Figure 2 It is a side schematic diagram of a pulverized coal combustion stabilization device provided in an embodiment of the present invention.

[0020] Figure 3 yes Figure 2 The schematic cross-sectional view of the pulverized coal combustion stabilization device along AA is shown.

[0021] Figure 4 It is a structural schematic diagram of the pulverized coal combustion stabilizing device provided in an embodiment of the present invention at the reflux cap.

[0022] Figure 5 It is a flow diagram of the coal powder fluid at the reflux cap of the coal powder stabilizing combustion device provided in an embodiment of the present invention.

[0023] Figure 6 It is a schematic diagram of fluid flow in a pulverized coal pipe assembly, a cleaning assembly and a secondary air assembly in a pulverized coal combustion stabilization device provided in an embodiment of the present invention.

[0024] Reference numerals: 100, pulverized coal combustion stabilizing device;

[0025] 10. Combustion stabilization chamber; 11. Acceleration tube; 111. First end; 112. Second end; 113. Injection port; 114. High-temperature acceleration zone; 12. Recirculation tube; 121. Third end; 122. Fourth end; 123. High-temperature recirculation zone; 13. Strengthening layer; 15. Cover shell;

[0026] 30. Cleaning assembly; 311. Air outlet; 312. Reduced diameter section; 313. Rectification channel; 314. Straight pipe section; 315. Wear-resistant coating;

[0027] 50. Pulverized coal pipe assembly; 51. Powder delivery port; 511. First return port; 512. Second return port; 52. Return cap; 521. First return channel; 522. Second return channel; 523. Guide plate; 53. Supply pipe; 531. First channel; 532. Second channel; 533. Inner pipe; 534. Outer pipe; 535. Side branch pipe;

[0028] 70. Secondary air assembly; 71. Air duct; 711. Air outlet; 721. Inner tube; 722. Middle tube; 723. Outer tube; 724. Air supply main tube; 725. Axial tube; 726. Radial tube; 73. Control valve; 74. Rotary vane; 75. Annular blunt body; 76. End plate. DETAILED DESCRIPTION

[0029] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0030] like Figures 1 to 6 As shown, an embodiment of the present invention provides a pulverized coal combustion stabilization device 100, which includes a burner and a stabilizer, at least part of which is located in the burner. The stabilizer includes an acceleration cylinder 11, a reflux cylinder 12, a cover 15, and a pulverized coal pipe assembly 50, wherein the cover 15 is disposed on the outside of the reflux cylinder 12, and a reinforcement layer 13 is disposed between the cover 15 and the reflux cylinder 12. The reflux cylinder 12 and the acceleration cylinder 11 are connected to define a stabilization chamber 10, and the pulverized coal pipe assembly 50 has a powder delivery port 51, which is disposed in the stabilization chamber 10 to deliver the pulverized coal fluid into the stabilization chamber 10.

[0031] Specifically, the cover 15, as an external protective layer, is tightly wrapped around the periphery of the reflux tube 12, which not only provides necessary protection for the entire flame stabilizer, but also helps to guide the reasonable distribution of airflow. In addition, a reinforcement layer 13 is added between the cover and the reflux tube 12, which not only significantly enhances the overall structural strength of the flame stabilizer, enabling it to withstand the high temperature and high pressure environment generated during the combustion process, but also effectively reduces the risk of material wear caused by long-term high-temperature operation and extends the service life of the equipment. The reflux tube 12 and the acceleration tube 11 jointly define a stable combustion chamber 10, and the powder delivery port 51 of the pulverized coal pipe assembly 50 is arranged in the stable combustion chamber 10, ensuring that the pulverized coal fluid can be delivered to the area in the best state, and then under the synergistic effect of the reflux tube 12 and the acceleration tube 11, the pulverized coal is fully mixed and efficiently burned.

[0032] In summary, the pulverized coal combustion stabilization device 100 in the embodiment of the present invention not only effectively enhances the structural strength and durability of the equipment, but also greatly improves the combustion efficiency and stability of the pulverized coal, bringing new solutions and technological breakthroughs to the field of industrial combustion.

[0033] In this embodiment, a wear-resistant coating 315 is provided on the outer side of the cover 15, so as to improve the wear resistance of the cover, extend the service life of the equipment, and reduce the cost and inconvenience caused by frequent replacement or maintenance.

[0034] Furthermore, the reinforcing layer 13 is made of heat-insulating cotton, which can prevent excessive heat from being lost from the recirculation tube 12 to the housing and make it too hot; on the other hand, it can maintain a relatively high temperature in the recirculation tube 12, promote rapid ignition and stable combustion of the coal powder, and improve the structural strength of the recirculation tube 12.

[0035] like Figure 1 , Figure 2 and Figure 3 As shown, in some embodiments, the acceleration cylinder 11 has a first end 111 and a second end 112 that are arranged oppositely, the diameter of the first end 111 is smaller than the diameter of the second end 112, and the first end 111 is provided with a jet port 113; the reflow cylinder 12 has a third end 121 and a fourth end 122 that are arranged oppositely, the diameter of the third end 121 is larger than the diameter of the fourth end 122, and the third end 121 of the reflow cylinder 12 is connected to the second end 112 of the acceleration cylinder 11. In other words, the acceleration cylinder 11 and the reflow cylinder 12 are both arranged in a similar cone-shaped structure, so that the stable combustion chamber can be a cylindrical structure with a large diameter in the middle and small diameters at both ends, so that the pulverized coal fluid injected through the powder delivery port 51 is rotated in the flow cylinder and smoothly ejected through the jet port 113 of the acceleration cylinder 11.

[0036] Furthermore, the combustion stabilization chamber 10 can be divided into a high-temperature reflux zone 123 located in the reflux cylinder 12 and a high-temperature acceleration zone 114 located in the acceleration cylinder 11. The powder delivery port 51 is located at the connection between the reflux cylinder 12 and the acceleration cylinder 11, and the opening of the powder delivery port 51 is set toward the high-temperature reflux zone 123, so that the pulverized coal fluid moves toward the high-temperature reflux zone 123, and after rotating in the high-temperature reflux zone 123, it flows toward the high-temperature acceleration zone 114, and then flows out through the injection port 113.

[0037] like Figure 3 , Figure 4 and Figure 5 As shown, in some embodiments, the pulverized coal pipe assembly 50 includes a first return channel 521 and a second return channel 522, and the powder delivery port 51 includes a first return port 511 located in the first return channel 521 and a second return port 512 located in the second return channel 522, the first return port 511 and the second return port 512 are connected, the opening of the first return port 511 and the opening of the second return port 512 are both set toward the inner wall of the return tube 12, and the straight line where the opening direction of the first return port 511 and the straight line where the opening direction of the second return port 512 are located intersect, so as to spray the pulverized coal fluid into the stable combustion chamber.

[0038] The opening direction of the first reflow port 511 is parallel to the axis of the reflow tube 12, and the opening direction of the second reflow port 512 is inclined from the center to the edge along the radial direction of the reflow tube 12. It can be imagined that the flow rate of the pulverized coal fluid in the first reflow channel 521 and the second reflow channel 522 can be adjusted as needed to change the injection angle of the pulverized coal fluid to meet different usage requirements.

[0039] Furthermore, the pulverized coal pipe assembly 50 also includes a reflux cap 52 and a guide plate 523. The first reflux channel 521 and the second reflux channel 522 are coaxially arranged in the reflux cap 52. The first reflux channel 521 is located on the outside of the second reflux channel 522. The guide plate 523 is arranged at the connection point between the first reflux port 511 and the second reflux port 512. The guide plate 523 is provided with an inclined surface on the side facing the second reflux channel 522, so that the pulverized coal fluid in the second reflux channel 522 fits the inclined surface of the guide plate 523 and is drained to the connection point between the first reflux port 511 and the second reflux port 512, and then the pulverized coal fluid in the first reflux channel 521 and the pulverized coal fluid in the second reflux channel 522 merge to form a stream of pulverized coal fluid, which is sprayed toward the combustion stabilization chamber 10.

[0040] In this embodiment, the angle between the straight line where the opening direction of the first return port 511 is located and the straight line where the opening direction of the second return port 512 is located can be set to β°. The pulverized coal fluid in the first return channel 521 can be the first fluid, and the pulverized coal fluid in the second return channel 522 can be the second fluid. The first fluid and the second fluid can converge at the connection point between the first return port 511 and the second return port 512, and then converge into a pulverized coal mixed fluid for jet ejection. In the above process, the jet momentum ratio of the first fluid and the second fluid can be changed by adjusting the flow rate of the first fluid and the second fluid, and the mutual induced effect between the first fluid and the second fluid can be changed, so that the ejection angle of the pulverized coal mixed fluid formed after the first fluid and the second fluid converge is finally made between 0° and β°. Among them, Figure 5 The arrow D indicates the flow direction of the first fluid, and the arrow E indicates the flow direction of the second fluid.

[0041] Among them, when the total amount of coal powder in the first return channel 521 and the second return channel 522 remains unchanged, if the flow rate of the first fluid is increased and the flow rate of the second fluid is reduced, the injection angle of the coal powder mixed fluid formed by the convergence will gradually approach β°; if the flow rate of the first fluid is reduced and the flow rate of the second fluid is increased, the injection angle of the coal powder mixed fluid formed by the convergence will gradually approach 0°.

[0042] It should be noted that when the injection angle of the pulverized coal mixed fluid increases, the radial velocity component of the pulverized coal mixed fluid flowing around will increase, and the axial velocity component will decrease, so that the overall flow velocity of the pulverized coal mixed fluid from right to left will decay faster, and it will turn early and flow from left to right, thereby achieving the purpose of reducing the axial length of the high-temperature recirculation zone 123. Similarly, when the injection angle of the pulverized coal mixed fluid decreases, the radial velocity component of the pulverized coal mixed fluid flowing around will decrease, and the axial velocity component will increase, so that the overall flow velocity of the pulverized coal mixed fluid from right to left will decay slower, and it will turn later and flow from left to right, thereby achieving the purpose of increasing the axial length of the high-temperature recirculation zone 123.

[0043] like Figure 3 As shown, in this embodiment, the pulverized coal pipe assembly 50 further includes a supply pipe 53, in which a first channel 531 and a second channel 532 are provided, the first channel 531 and the second channel 532 are independent of each other, the first channel 531 is connected to the first return channel 521, and the second channel 532 is connected to the second return channel 522, and the first channel 531 and the second channel 532 are used for conveying different types of pulverized coal fluids to the combustion stabilization chamber 10. It should be noted that different types of pulverized coal fluids may have different flow rates or different concentrations of pulverized coal fluids. In this embodiment, the pulverized coal fluids have different flow rates.

[0044] Furthermore, the supply pipe 53 includes an inner pipe 533 and an outer pipe 534. The inner pipe 533 is hollow to form a first channel 531. The outer pipe 534 is sleeved on the outside of the inner pipe 533. A second channel 532 is formed between the outer pipe 534 and the inner pipe 533, thereby ensuring that the two channels are independent of each other and do not interfere with each other, and providing a strong guarantee for the stable transportation of the coal powder fluid.

[0045] Furthermore, the supply pipe 53 further includes a side branch pipe 535 connected to the second channel 532 . The side branch pipe 535 is cylindrical, and the axis of the side branch pipe 535 is perpendicular to the axis of the outer pipe 534 . The side branch pipe 535 is used to transport the pulverized coal fluid to the second channel 532 .

[0046] like Figure 3As shown, in some embodiments, the coal powder stabilizing combustion device 100 also includes a secondary air component 70, and the secondary air component 70 includes a plurality of independent air ducts 71, and the air duct 71 has an air supply port 711, and the air supply port 711 is arranged at one end of the reflow tube 12, and the first reflow port 511 and the second reflow port 512 are arranged at the other end of the reflow tube 12, and the air supply port 711 is relative to the first reflow port 511 and the second reflow port 512, and the air supply port 711 is staggered in the radial direction of the stabilizing combustion chamber 10 relative to the first reflow port 511 and the second reflow port 512, which can not only adjust the radial width of the coal powder fluid in the high-temperature reflow zone 123, but also provide assistance to the coal powder fluid in the high-temperature reflow zone 123, thereby accelerating the flow speed of the coal powder fluid toward the injection port 113.

[0047] Specifically, the multiple air ducts 71 are not simply arranged side by side or randomly distributed, but are coaxially arranged and mutually nested. Due to the mutual nesting between the air ducts 71, the corresponding air supply ports 711 also present the characteristics of being annularly arranged and mutually nested. This means that when the airflow passes through these air supply ports 711, they will be evenly blown into the high-temperature recirculation zone 123 in the form of an annular wind. This annular wind design not only improves the coverage of the airflow, but also makes the distribution of the airflow in the recirculation tube 12 more uniform, thereby further improving the combustion efficiency and stability of the coal powder.

[0048] Moreover, the central axis of the air supply port 711 completely coincides with the axis of the return tube 12, which not only ensures that the airflow can be evenly distributed along the axis of the return tube 12, but also avoids the deviation or turbulence of the airflow during the transportation process. Such a layout not only improves the transportation efficiency of the airflow, but also makes the combustion process more stable and controllable.

[0049] In this embodiment, three air ducts 71 are provided. The pulverized coal-free pipe assembly 50 may include an inner layer pipe 721, a middle layer pipe 722 and an outer layer pipe 723, which are arranged in sequence along the radial direction of the stable combustion chamber 10, and three air ducts 71 are provided correspondingly between the inner layer pipe 721, the middle layer pipe 722 and the outer layer pipe 723. Among them, the inner layer pipe 721 is sleeved on the outer side of the outer pipe 534 of the pulverized coal pipe, and the outer layer pipe 723 is penetrated in the housing, so that the overall structure can be made more compact.

[0050] Furthermore, the secondary air assembly 70 further includes an air supply main pipe 724, which is connected to the air duct 71, so as to provide a stable airflow for the air duct 71. In addition, the inner layer pipe 721, the middle layer pipe 722 and the outer layer pipe 723 all include an axial pipe 725 and a radial pipe 726, the axial pipe 725 is extended along the axial direction of the return cylinder 12, the radial pipe 726 is extended along the radial direction of the return cylinder 12, and the radial pipe 726 is connected between the axial pipe 725 and the air supply main pipe 724, so that the air duct 71 is arranged in a Z shape, making the overall structure more compact.

[0051] Furthermore, the secondary air assembly 70 further includes a plurality of regulating valves 73, which are arranged one by one on the air duct 71, and the regulating valves 73 are used to adjust the flow rate of the airflow in the air duct 71. And the airflow in the air duct 71 can be opened and closed by opening and closing the regulating valves 73, so that the radial width of the pulverized coal mixed fluid in the high-temperature recirculation zone 123 can be changed. In other words, the secondary air assembly 70 can provide a multi-layer airflow wrapped from the inside to the outside, and the radial width of the multi-layer airflow in the recirculation tube 12 can be changed by closing or reducing the regulating valves 73 on the inner tube 721, the middle tube 722 and the outer tube 723, so that the radial width of the high-temperature recirculation zone 123 can be adjusted.

[0052] In some embodiments, the secondary air assembly 70 further includes a plurality of rotor blades 74, which are arranged one by one at the air outlet 711 of the air duct 71, and the rotor blades 74 are used to guide the airflow delivered by the air duct 71 to form a rotating airflow in the stable combustion chamber 10. The rotor blades 74 are a plurality of guide vane structures uniformly arranged along the circumference of the air duct 71, and each guide vane is arranged at an angle with the axial direction of the air duct 71, and the angle can be set to 30° to 80°, so that the airflow flowing through the rotor blades 74 can be a rotating fluid with an axial velocity and a tangential velocity, and then sprayed into the high-temperature reflow zone 123 of the reflow cylinder 12.

[0053] In some embodiments, the air duct 71 and the pulverized coal pipe assembly 50 are coaxially arranged, the air duct 71 is arranged outside the pulverized coal pipe assembly 50, an annular bluff 75 is arranged between the air duct 71 and the pulverized coal pipe assembly 50, and the annular bluff 75 is located at the first end 111 of the return tube 12. The annular bluff 75 can be arranged between the inner layer tube 721 and the outer tube 534 of the pulverized coal pipe assembly 50.

[0054] Furthermore, the secondary air assembly 70 also includes an end plate 76, which is a circular flat plate structure. The left ends of the outer tube 534, the inner tube 721, the middle tube 722 and the outer tube 723 are connected to the end plate 76 to realize the connection between the pulverized coal pipe assembly 50 and the secondary air assembly 70.

[0055] In some embodiments, the coal powder stabilizing combustion device 100 also includes a cleaning assembly 30, which includes a cleaning flow channel located between the cover and the reflux cylinder 12, and the cleaning flow channel has an air outlet 311, and the air outlet 311 is arranged at the second end 112 of the acceleration cylinder 11. The opening of the air outlet 311 is arranged toward the inner wall of the acceleration cylinder 11, so that the airflow in the cover can be ejected toward the inner wall of the acceleration cylinder 11, so that the gas in the cover can clean the inner wall of the stabilizing combustion chamber 10 to avoid coking.

[0056] Specifically, the cleaning component 30 sprays air toward the inner wall of the acceleration cylinder 11 through the air outlet 311 toward the inner wall of the acceleration cylinder 11, so that the airflow impacts the inner wall of the acceleration cylinder 11, and effectively removes foreign matter such as coal powder particles adhered to the inner wall of the acceleration cylinder 11, which not only avoids the influence of coal powder adhesion on the performance of the acceleration cylinder 11, but also accelerates the mixed fluid again through the flushing effect of the airflow, so that the flow speed of the mixed fluid at the injection port 113 is further improved.

[0057] In some embodiments, a plurality of openings are provided between the reflow cylinder 12 and the acceleration cylinder 11 to form an air outlet 311 for the airflow in the housing to flow into the combustion stabilization chamber 10. The housing 15 includes a reduced diameter section 312, which is connected to the second end 112 of the acceleration cylinder 11. A rectifier channel 313 is provided between the reduced diameter section 312 and the reflow cylinder. The flow gap of the rectifier channel 313 is reduced to guide the airflow in the housing so that the airflow can flow smoothly and orderly to the inner wall of the acceleration cylinder 11, thereby avoiding the turbulence and eddy current that may occur during the flow of the airflow. At the same time, the gap between the reduced diameter section 312 and the reflow cylinder 12 becomes smaller, which can also increase the resistance along the flow of the airflow, making the airflow ejected through the air outlet 311 more uniform, and can also increase the jet velocity of the airflow, so that the airflow flows forward along the inner wall of the acceleration cylinder 11 with a high momentum.

[0058] Furthermore, the cover, the reflow cylinder 12 and the acceleration cylinder 11 are all configured to be cylindrical, and a plurality of openings are evenly arranged along the cylinder wall of the acceleration cylinder 11, so that the airflow ejected from the cover through the air outlet 311 is more evenly distributed on the cylinder wall of the acceleration cylinder 11, thereby avoiding the problem of excessive local flushing or insufficient cleaning caused by uneven airflow distribution, and ensuring that every area of ​​the inner wall of the acceleration cylinder 11 can be adequately cleaned and covered by airflow.

[0059] Furthermore, the housing includes a straight pipe section 314, which is connected to the reduced diameter section 312, and the straight pipe section 314 is sleeved on the outside of the reflux tube 12. On the one hand, it provides a stable and smooth channel for the airflow in the housing, avoiding the problems of increased airflow resistance and reduced flow rate caused by pipe bending or deformation, and ensuring that the airflow in the housing can flow smoothly to the acceleration tube 11 at a higher speed, thereby improving the cleaning effect and the acceleration performance of the gas. On the other hand, the straight pipe section 314 is sleeved on the outside of the reflux tube 12, making the structure of the entire coal powder stabilizing combustion device 100 more compact and efficient, which not only improves the space utilization, but also reduces the overall size and weight of the equipment, making the coal powder stabilizing combustion device 100 more convenient and flexible during installation and operation.

[0060] like Figure 6 As shown, arrow D indicates the flow direction of the pulverized coal fluid in the first channel; arrow E indicates the flow direction of the pulverized coal fluid in the second channel; arrow F indicates the flow direction of the airflow in the secondary air assembly; arrow G indicates the flow direction of the airflow in the cleaning assembly; arrow H indicates the rotation direction of the pulverized coal fluid in the high-temperature recirculation zone; length M is the axial length of the high-temperature recirculation zone; length N is the radial length of the high-temperature recirculation zone. During the use of the above-mentioned pulverized coal combustion stabilizing device 100, one of the two pulverized coal fluids flows toward the first reflow port 511 through the first channel 531 and the first reflow channel 521, and the other of the two pulverized coal fluids flows toward the second reflow port 512 through the second channel 532 and the second reflow channel 522. The two pulverized coal fluids converge into a pulverized coal mixed fluid at the connection point between the first reflow port 511 and the second reflow port 512, and are sprayed into the high-temperature reflow zone 123 in the reflow tube 12 from right to left along the axial direction of the reflow tube 12;

[0061] At the same time, the secondary air assembly 70 divides the secondary air into three air streams through the air supply main pipe 724, and injects them into the inner tube 721, the middle tube 722 and the outer tube 723 respectively, and then injects them into the high-temperature recirculation zone 123 of the recirculation tube 12 from left to right under the rotation and guidance of the rotary vane 74 and along the axial direction of the recirculation tube 12, so that three layers of rotating airflow wrapped from inside to outside can be formed on the left side of the recirculation tube 12, which can not only provide oxygen for coal powder combustion, but also enhance the entrainment effect of high-temperature airflow by constructing a low-pressure zone inside the rotating airflow, and further promote the formation and maintenance of the high-temperature recirculation zone 123. At the same time, the radial width of the multi-layer airflow in the recirculation tube 12 can be changed by closing or reducing the regulating valves 73 on the inner tube 721, the middle tube 722 and the outer tube 723, so that the radial width of the high-temperature recirculation zone 123 can be adjusted.

[0062] In addition, the airflow in the cleaning component 30 can be injected into the acceleration cylinder 11 from left to right along the axial direction of the reflow cylinder 12 through the cleaning air duct 71 and the air outlet 311, and flow at high speed along the inner wall of the acceleration cylinder 11, thereby wrapping and carrying the jet flame located in the center to flow out, ensuring the good rigidity of the center flame.

[0063] When the acceleration cylinder 11 and the injection port 113 are cleverly arranged inside the burner, these high-temperature flames can quickly ignite the coal powder airflow around the injection port 113, thereby achieving efficient and stable combustion of the coal powder.

[0064] In summary, under the joint action of the pulverized coal pipe assembly 50, the secondary air assembly 70 and the cleaning assembly 30, a high-temperature recirculation zone 123 can be formed inside the reflux cylinder 12, and a high-temperature flame can be generated. Then, under the acceleration action of the acceleration cylinder 11, a high-temperature jet flame is ejected at high speed through the injection port 113 to form the pulverized coal airflow that has not yet been burned around the injection port 113 in the burner, thereby realizing efficient and continuous combustion of the pulverized coal.

[0065] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0066] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0067] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0068] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0069] In the present invention, the terms "one embodiment", "some embodiments", etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0070] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A pulverized coal combustion stabilization device, characterized in that: It includes a burner and a flame stabilizer, at least part of which is located inside the burner; the flame stabilizer includes a cover, a reflux cylinder, an acceleration cylinder and a pulverized coal pipe assembly, the cover is arranged on the outside of the reflux cylinder, and a reinforcement layer is provided between the cover and the reflux cylinder; the reflux cylinder and the acceleration cylinder are connected to define a stabilizing combustion chamber, and the pulverized coal pipe assembly has a powder delivery port, which is provided in the stabilizing combustion chamber to deliver the pulverized coal fluid into the stabilizing combustion chamber.

2. The pulverized coal combustion stabilization device according to claim 1, characterized in that: The acceleration cylinder has a first end and a second end that are arranged opposite to each other, the diameter of the first end is smaller than the diameter of the second end, and the first end is provided with a jet port; the reflux cylinder has a third end and a fourth end that are arranged opposite to each other, the diameter of the third end is larger than the diameter of the fourth end, and the third end of the reflux cylinder is connected to the second end of the acceleration cylinder.

3. The pulverized coal combustion stabilization device according to claim 1, characterized in that: The outer side of the cover shell is provided with a wear-resistant coating; And / or, the reinforcement layer is made of thermal insulation cotton.

4. The pulverized coal combustion stabilization device according to claim 1, characterized in that: The pulverized coal pipe assembly includes a first reflow channel and a second reflow channel, and the powder delivery port includes a first reflow port located in the first reflow channel and a second reflow port located in the second reflow channel. The first reflow port and the second reflow port are connected, and the opening of the first reflow port and the opening of the second reflow port are both arranged toward the inner wall of the reflow cylinder. The straight line where the opening direction of the first reflow port is located and the straight line where the opening direction of the second reflow port is located intersect, so as to spray the pulverized coal fluid into the stable combustion chamber.

5. The pulverized coal combustion stabilization device according to claim 4, characterized in that: The pulverized coal pipe assembly includes a reflux cap and a guide plate. The first reflux channel and the second reflux channel are coaxially arranged in the reflux cap. The first reflux channel is located on the outside of the second reflux channel. The guide plate is arranged at the connection point between the first reflux port and the second reflux port. The guide plate is provided with an inclined surface on the side facing the second reflux channel.

6. The pulverized coal combustion stabilization device according to claim 4, characterized in that: The pulverized coal pipe assembly includes a supply pipe, in which a first channel and a second channel are provided. The first channel is connected to the first return channel, and the second channel is connected to the second return channel. The first channel and the second channel are used to transport different types of pulverized coal fluids into the combustion stabilization chamber.

7. The pulverized coal combustion stabilization device according to claim 4, characterized in that: It also includes a secondary air component, which includes a plurality of independent air ducts, each of which has an air supply port, wherein the air supply port is arranged at one end of the reflux cylinder, and the powder supply port is arranged at the other end of the reflux cylinder, and the air supply port is staggered relative to the powder supply port in the radial direction of the combustion stabilization chamber.

8. The pulverized coal combustion stabilization device according to claim 7, characterized in that: The secondary air component further includes a plurality of regulating valves, which are arranged on the air duct in a one-to-one correspondence, and the regulating valves are used to adjust the flow rate of the air flow in the air duct.

9. The pulverized coal combustion stabilization device according to claim 7, characterized in that: The secondary air component also includes a plurality of rotors, which are arranged one by one at the air supply port of the air duct. The rotors are used to guide the airflow transported by the air duct to form a rotating airflow in the combustion stabilization chamber.

10. The pulverized coal combustion stabilization device according to claim 7, characterized in that: The air duct and the pulverized coal pipe assembly are coaxially arranged, the air duct is arranged outside the pulverized coal pipe assembly, and an annular blunt body is arranged between the air duct and the pulverized coal pipe assembly.

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