Coal-fired unit combustion stabilizer

Abstract

This invention discloses a combustion stabilization device for coal-fired power units. The device includes a burner and a stabilizer, which are connected to the burner and extend along a first direction. The stabilizer includes a shell and a pulverized coal pipe assembly. The shell includes a cavity, and at least a portion of the pulverized coal pipe assembly is disposed within the cavity. The outer circumferential surface of the pulverized coal pipe assembly is sealed to the shell. The pulverized coal pipe assembly contains a first channel and a second channel, which are spaced apart within the assembly and both communicate with the cavity. The outlet of the first channel is adjacent to the inlet end of the pulverized coal pipe assembly relative to the outlet of the second channel. Therefore, the combustion stabilization device for coal-fired power units according to this invention has advantages such as good combustion stability, good environmental performance, and low production cost.

Description

Technical Field

[0001] This invention relates to the field of pulverized coal combustion technology, specifically to a combustion stabilization device for coal-fired power units. Background Technology

[0002] To improve the stable combustion capability of coal-fired power plants during low-load and variable-load operation, it is usually necessary to add ignition devices or introduce auxiliary fuel. In related technologies, ignition devices are commonly used, often employing diesel fuel. This consumes a large amount of diesel during ignition, increasing operating costs and generating significant amounts of sulfur-containing waste gas, resulting in poor environmental performance. Furthermore, pulverized coal combustion is often incomplete, leading to low combustion efficiency. Summary of the Invention

[0003] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a combustion stabilization device for coal-fired power units that offers good combustion stability and environmental benefits.

[0004] The coal-fired power unit combustion stabilization device of this invention includes:

[0005] A burner and a flame stabilizer, wherein the flame stabilizer is connected to the burner and extends along a first direction, the first direction including a first sub-direction and a second sub-direction opposite to the first sub-direction, and the direction from the inlet end of the flame stabilizer to the outlet end of the flame stabilizer is the first sub-direction;

[0006] The flame stabilizer includes:

[0007] A housing, the housing including a cavity;

[0008] A pulverized coal pipe assembly, at least a portion of which is disposed within the cavity, wherein the outer peripheral surface of the pulverized coal pipe assembly is sealed to the housing; the pulverized coal pipe assembly is provided with a first channel and a second channel, which are spaced apart within the pulverized coal pipe assembly, and both the first channel and the second channel communicate with the cavity, wherein the outlet of the first channel is adjacent to the inlet end of the pulverized coal pipe assembly relative to the outlet of the second channel;

[0009] A condenser is disposed inside the pulverized coal pipe assembly. The condenser can split the primary air pulverized coal gas flow entering the pulverized coal pipe assembly into a first sub-gas flow and a second sub-gas flow. The pulverized coal concentration of the first sub-gas flow is less than that of the second sub-gas flow. The first channel is used for the passage of the first sub-gas flow, and the second channel is used for the passage of the second sub-gas flow.

[0010] A secondary air duct, which is connected to the cavity.

[0011] Therefore, the coal-fired power unit combustion stabilization device of the present invention has the advantages of good combustion stability, good environmental protection effect and low production cost.

[0012] In some embodiments, the burner includes:

[0013] A feeding tube assembly, comprising a first feeding tube and a second feeding tube arranged sequentially and at intervals in the first sub-direction, wherein the first feeding tube is provided with a first flow path.

[0014] A combustion tube assembly is provided, wherein a combustion chamber is provided within the combustion tube assembly, and a feeding pipe assembly is connected to the combustion tube assembly. The combustion tube assembly extends along a first direction and is provided with a second flow path and a third flow path. The first flow path, the second flow path, and the third flow path are all connected to the combustion chamber. The first flow path, the second flow path, and the third flow path are spaced apart in the first direction. The second feeding pipe is connected to both the second flow path and the third flow path. The outlet end of the combustion tube assembly is adapted to be connected to a combustion furnace. The outlet end of the flame stabilizer extends through the side wall of the first feeding pipe into the first flow path so as to communicate with the combustion chamber.

[0015] In some embodiments, the pulverized coal pipe assembly includes a first inlet, a first outlet, and a second outlet. The first inlet, the first outlet, and the second outlet are all disposed on the pulverized coal pipe assembly and arranged sequentially and at intervals along a first sub-direction. The first inlet and the first outlet are connected through the first channel, and the first inlet and the second outlet are connected through the second channel. The openings of the first outlet and the second outlet are both disposed facing the inlet end of the pulverized coal pipe assembly.

[0016] In some embodiments, the pulverized coal pipe assembly includes:

[0017] The first tube has a first inlet at its inlet end;

[0018] The second tube and the condenser are both disposed inside the first tube. The condenser and the second tube are arranged sequentially and at intervals in the first sub-direction. The inner peripheral wall of the first tube and the outer peripheral wall of the second tube define a first sub-channel, and the inner peripheral wall of the second tube defines a second channel.

[0019] In some embodiments, the pulverized coal pipe assembly further includes:

[0020] The first return element is sleeved on the outer periphery of the second tube and connected to the outlet end of the second tube. The outlet end of the first tube extends between the first return element and the second tube, so that the inner peripheral wall of the first return element and the outer peripheral wall of the first tube define a return channel communicating with the first sub-channel, and the opening of the return channel faces the inlet end of the first tube to form the first outlet.

[0021] The second return element is arranged sequentially and at intervals in the first sub-direction, with a portion of the second return element sleeved on the outer periphery of the first return element to form the second outlet.

[0022] In some embodiments, the housing includes a first segment, a second segment, a third segment, and a fourth segment connected sequentially in the first direction. The first segment and the third segment are both cylindrical. The cross-sectional area of ​​the second segment gradually increases along the first sub-direction, and the cross-sectional area of ​​the fourth segment gradually decreases along the first sub-direction. The first outlet is located in the second segment, and the second outlet is located in the third segment.

[0023] In some embodiments, the concentrator is annular and its inner peripheral wall defines a concentration adjustment channel. The outer peripheral wall of the concentrator is in contact with the inner peripheral wall of the first tube. The concentrator includes a tapering section and a expanding section arranged sequentially along the first sub-direction. The cross-sectional area of ​​the tapering section gradually increases along the first sub-direction, and the cross-sectional area of ​​the expanding section gradually decreases along the first sub-direction, so that the cross-sectional area of ​​the concentration adjustment channel first gradually decreases and then gradually increases along the first sub-direction.

[0024] In some embodiments, the combustion tube assembly includes an inner tube with a cavity to form the combustion chamber. The inner tube includes a first combustion section and a second combustion section, which are arranged sequentially and communicate with each other in the first sub-direction. The outlet end of the first combustion section extends into the inlet end of the second combustion section, such that the outer peripheral wall of the first combustion section and the inner peripheral wall of the second combustion section define the second flow path.

[0025] In some embodiments, the combustion tube assembly further includes an outer tube, which is sleeved outside the inner tube and the inner peripheral wall of the outer tube is spaced apart from the outer peripheral wall of the inner tube. The outer tube includes a rectifier section and a guide section arranged sequentially along the first sub-direction. The inlet end of the rectifier section is sealed to the inlet end of the first combustion section, and the inner peripheral wall of the guide section and the outer peripheral wall of the second combustion section define a third flow path.

[0026] In some embodiments, the first feed tube includes:

[0027] A first transition section is connected to the first combustion section, the first transition section extends along the first direction, and the cross-sectional area of ​​the first transition section gradually decreases along the first sub-direction;

[0028] The first feeding section has an inlet end that extends along a second direction, which is orthogonal to the first direction, and an outlet end that extends along the first direction. The first feeding section is connected to the first transition section, and the first feeding section and the first transition section are connected to form the first flow path. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of the coal-fired power unit combustion stabilization device according to an embodiment of the present invention.

[0030] Figure 2 This is a schematic diagram of the structure of the combustion stabilizer in the coal-fired power unit combustion stabilization device according to an embodiment of the present invention.

[0031] Figure 3 yes Figure 2 The left view.

[0032] Figure 4 This is a schematic diagram of the internal airflow direction of the combustion stabilization device for coal-fired power units according to an embodiment of the present invention.

[0033] Figure 5 This is a schematic diagram of the internal airflow direction of the combustion stabilizer in the combustion stabilization device of a coal-fired power unit according to an embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram of the internal airflow direction of the burner in the combustion stabilization device of a coal-fired power unit according to an embodiment of the present invention.

[0035] Figure 7 This is a schematic diagram of the air supply pipe of the burner in the combustion stabilization device of a coal-fired power unit according to an embodiment of the present invention.

[0036] Figure 8 This is a schematic diagram of the structure of another air supply pipe of the burner in the combustion stabilization device of the coal-fired power unit according to an embodiment of the present invention.

[0037] Figure label:

[0038] Flame stabilizer 100; Pulverized coal pipe assembly 11; First pipe 111; First inlet 1111; Concentrator 1112; Converging section 11121; Expanding section 11122; Second pipe 112; First return section 113; Second return section 114; First outlet 115; Second outlet 116; First channel 117; Second channel 118; Return channel 119; Shell 12; First section 121; Second section 122; Third section 123; Fourth section 124; Flame stabilizer outlet 125; Secondary air duct 13;

[0039] Burner 200; Combustion tube assembly 21; Inner tube 211; First combustion section 2111; Second combustion section 2112; Outer tube 212; Rectifying section 2121; Guide section 2122; Second flow path 213; Third flow path 214; First flow path 215; Feed pipe assembly 22; First feed pipe 221; First feed section 2211; First transition section 2212; Second feed pipe 222; Second transition section 2221; Tertiary air duct 23; First nozzle 231; Second nozzle 232; Blade 234; Third nozzle 233. Detailed Implementation

[0040] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0041] like Figure 1-8 As shown, the coal-fired power unit combustion stabilization device of this embodiment includes a burner 200 and a combustion stabilizer 100.

[0042] The flame stabilizer 100 is connected to the burner 200. The flame stabilizer 100 extends along a first direction, which includes a first sub-direction and a second sub-direction opposite to the first sub-direction. The direction from the inlet end of the flame stabilizer 100 to the outlet end of the flame stabilizer 100 is the first sub-direction.

[0043] The flame stabilizer 100 includes a housing 12, a pulverized coal pipe assembly 11, a secondary air duct 13, and a concentrator 1112.

[0044] The housing 12 includes a cavity.

[0045] At least a portion of the pulverized coal pipe assembly 11 is disposed within the cavity. The outer peripheral surface of the pulverized coal pipe assembly 11 is sealed to the housing 12. The pulverized coal pipe assembly 11 is provided with a first channel 117 and a second channel 118. The first channel 117 and the second channel 118 are spaced apart within the pulverized coal pipe assembly 11. Both the first channel 117 and the second channel 118 are connected to the cavity, and the outlet of the first channel 117 is adjacent to the inlet end of the pulverized coal pipe assembly 11 relative to the outlet of the second channel 118.

[0046] The condenser 1112 is installed inside the pulverized coal pipe assembly 11. The condenser 1112 can split the primary air pulverized coal airflow entering the pulverized coal pipe assembly 11 into a first sub-airflow and a second sub-airflow. The pulverized coal concentration of the first sub-airflow is less than that of the second sub-airflow. The first channel 117 is used to allow the first sub-airflow to pass through, and the second channel 118 is used to allow the second sub-airflow to pass through.

[0047] Secondary air duct 13 is connected to the cavity.

[0048] For example, for ease of description, the following will use... Figure 1 The left and right directions are taken as the first direction, with the right being the first sub-direction and the left being the second sub-direction.

[0049] For example, the housing 12 has a cavity, the pulverized coal pipe assembly 11 extends in the left and right direction, the center line of the pulverized coal pipe assembly 11 coincides with the center line of the housing 12, the left end of the pulverized coal pipe assembly 11 is located outside the housing 12, and the right end of the pulverized coal pipe assembly 11 is located inside the housing 12.

[0050] A sealing plate is provided at the left end of the housing 12, and an installation port is provided in the middle of the sealing plate. The pulverized coal pipe assembly 11 is fixed inside the housing 12 through the installation port, and the outer peripheral wall of the pulverized coal pipe assembly 11 is sealed to the inner peripheral wall of the installation port. A flame stabilizer outlet 125 is provided at the right end of the housing 12.

[0051] The pulverized coal pipe assembly 11 is provided with a first channel 117 and a second channel 118, which are spaced apart. Both the first channel 117 and the second channel 118 are connected to the cavity. The outlet of the first channel 117 is located to the left of the outlet of the second channel 118.

[0052] The secondary air duct 13 contains a secondary air channel, which can be connected to the cavity to introduce secondary air into the cavity.

[0053] When the stabilizer 100 of the coal-fired power unit stabilization device of this embodiment is working, the primary air flow provided by the pulverized coal gas source enters the pulverized coal pipe assembly 11. After being concentrated by the condenser 1112, the primary air pulverized coal flow is split into a first sub-flow and a second sub-flow. The pulverized coal concentration of the first sub-flow is less than that of the second sub-flow. The first sub-flow flows from the first channel 117 into the cavity, and the second sub-flow flows from the second channel 118 into the cavity.

[0054] At the same time, the secondary air is injected into the cavity at high speed along the secondary air duct 13. It gradually flows to the right in the cavity and forms a high-speed rotating airflow. Because the secondary air has a large rotational tangential velocity at this time, a low-pressure area is formed in the central area of ​​the secondary air during the high-speed rotating flow.

[0055] As the secondary wind gradually flows to the right, some of it will flow into the low-pressure area, thus forming a high-speed recirculation zone within the shell 12.

[0056] Because the outlet of the second channel 118 is located near the high-speed recirculation zone, the second sub-gas flow is injected near the high-speed recirculation zone. This makes it easier for the second sub-gas flow to be entrained into the high-speed recirculation zone during its flow, igniting some of the coal powder in the second sub-gas flow. This allows the second sub-gas flow to swirl and burn, releasing heat, thereby igniting all the coal powder in the second sub-gas flow and forming a dense-phase high-temperature recirculation zone. This will help promote the rapid heating and ignition of the second sub-gas flow and release more heat, ensuring stable combustion of the coal powder in the dense-phase high-temperature recirculation zone. At the same time, the first sub-gas flow is injected into the cavity at a certain distance to the left of the second sub-gas flow. The first sub-gas flow is blocked and carried by the secondary wind in the swirling state, thus changing its direction. The first sub-gas flow enters the dense-phase high-temperature recirculation zone between the secondary wind in the swirling state and the second sub-gas flow.

[0057] In this process, although the coal powder concentration in the first sub-gas stream is low and not easily ignited, on the one hand, the low concentration of coal powder in the first sub-gas stream is subjected to convective and radiative heat transfer in the high-temperature reflux zone, which can promote the heating and ignition of the first sub-gas stream. On the other hand, the outlet position of the first channel 117 is located to the left of the outlet position of the second channel 118, so that the first sub-gas stream enters the cavity to the left of the second sub-gas stream, thereby giving the first sub-gas stream a longer residence time relative to the second sub-gas stream within the shell 12. These two aspects will jointly promote the ignition and burnout effect of the first sub-gas stream. At this time, the first sub-gas stream is preheated, rapidly heats up and ignites, and releases a large amount of heat, forming a light-phase high-temperature reflux zone outside the dense-phase high-temperature reflux zone.

[0058] Meanwhile, since the second sub-gas flow is injected at a certain distance from the first sub-gas flow, it helps to delay the mixing of rich and lean gas flows. This promotes overall burnout and enhances the rich and lean combustion effect of pulverized coal, thereby reducing NOx formation.

[0059] Then, the flame is ejected at high speed from the burner outlet 125 and then enters the burner 200.

[0060] The flame stabilizer 100 of the coal-fired power unit combustion stabilization device according to the embodiments of the present invention has the following advantages:

[0061] (1) Significant economic advantages.

[0062] Compared to traditional micro-oil igniters and plasma igniters, this invention offers significant economic advantages. This invention only requires igniting a portion of the pulverized coal in the second sub-gas stream to achieve the effect of igniting most of the surrounding pulverized coal with a small amount of coal. It completely replaces traditional micro-oil igniters and plasma igniters, using coal as fuel for direct ignition. This achieves the goal of igniting a large amount of surrounding pulverized coal with a small amount of coal, improving the economy of coal-fired power units during ignition and peak-shaving processes, and reducing production costs.

[0063] (2) Rapid ignition and strong low-load stable combustion capability

[0064] This invention, by constructing a coal-fired power unit with both rich and lean combustion and secondary coal ignition preheating inside the combustion stabilizer 100 without combustion aid, helps to achieve rapid ignition during the start-up process of coal-fired power units and stable combustion during flexible peak shaving, while also promoting the burnout effect of coal during combustion.

[0065] (3) Reduce NOx generation

[0066] By constructing a coal-pulverized coal enrichment and lean combustion system and a two-stage high-temperature reduction zone inside the combustion stabilizer 100 without combustion aid, the formation of fuel-type NOx is reduced. Furthermore, the presence of multiple high-temperature zones results in a more uniform overall temperature distribution within the combustion stabilizer 100, which helps reduce the formation of thermal NOx and improves environmental performance.

[0067] Therefore, the coal-fired power unit combustion stabilization device of the present invention has the advantages of good combustion stability, good environmental protection effect and low production cost.

[0068] Optionally, such as Figure 2 and Figure 3 As shown, the secondary air duct 13 is located on the outer periphery of the first section 121 and connected to the first section 121. The air outlet direction of the secondary air duct 13 is tangent to the inner periphery of the first section 121. There are multiple secondary air ducts 13, which are arranged at intervals along the circumference of the first section 121.

[0069] For example, secondary air duct 13 is located on the outer periphery of the first section 121 and connected to the first section 121. The air outlet direction of the secondary air duct 13 is tangent to the inner peripheral wall of the first section 121. In other words, a secondary air channel is provided inside the secondary air duct 13, and the secondary air channel is tangent to the inner peripheral wall of the first section 121. There are multiple secondary air ducts 13, such as two to six. Optionally, there are two, three, or six secondary air ducts 13.

[0070] In the combustion stabilizer 100 of the coal-fired power unit combustion stabilizer of this embodiment of the invention, the air outlet direction of the secondary air duct 13 is tangent to the inner peripheral wall of the shell 12, so that the secondary air rotates and flows at high speed, forming a low-pressure zone in the central region of the secondary air.

[0071] In some embodiments, such as Figure 1 As shown, the burner 200 includes a feed tube assembly 22 and a combustion tube assembly 21.

[0072] The feeding tube assembly 22 includes a first feeding tube 221 and a second feeding tube 222 arranged sequentially and at intervals in the first sub-direction, and the first feeding tube 221 is provided with a first flow path 215.

[0073] The combustion tube assembly 21 has a combustion chamber inside. The feeding pipe assembly 22 is connected to the combustion tube assembly 21. The combustion tube assembly 21 extends along a first direction. The combustion tube assembly 21 has a second flow path 213 and a third flow path 214 inside. The first flow path 215, the second flow path 213 and the third flow path 214 are all connected to the combustion chamber. The first flow path 215, the second flow path 213 and the third flow path 214 are spaced apart in the first direction. The second feeding pipe 222 is connected to the second flow path 213 and the third flow path 214. The outlet end of the combustion tube assembly 21 is adapted to be connected to the combustion furnace. The outlet end of the flame stabilizer 100 passes through the side wall of the first feeding pipe 221 and extends into the first flow path 215 so as to communicate with the combustion chamber.

[0074] For example, the feed pipe assembly 22 is used to supply fuel to the combustion pipe assembly 21. The feed pipe assembly 22 is provided with a first flow path 215. The right end of the combustion pipe assembly 21 is adapted to be connected to the combustion furnace so that the flame in the combustion chamber can enter the combustion furnace.

[0075] The combustion tube assembly 21 extends in the left-right direction. The combustion tube assembly 21 is also provided with a second flow path 213 and a third flow path 214. The first flow path 215 is located to the left of the second flow path 213, and the second flow path 213 is located to the left of the third flow path 214. The connection between the first flow path 215 and the combustion chamber is located to the left of the connection between the second flow path 213 and the combustion chamber, and the connection between the second flow path 213 and the combustion chamber is located to the left of the connection between the third flow path 214 and the combustion chamber.

[0076] For ease of description, the first feed pipe 221 provides a second airflow to the combustion chamber. In other words, the first flow path 215 provides a second airflow to the combustion chamber, and the second feed pipe 222 provides a third airflow to the combustion chamber. The third airflow is divided into a third sub-airflow and a fourth sub-airflow. The third sub-airflow enters the combustion chamber from the second flow path 213, and the fourth sub-airflow enters the combustion chamber from the third flow path 214.

[0077] A through hole is provided on the side wall of the first feeding pipe 221. The flame stabilizer 100 is installed in the through hole, and the housing 12 of the flame stabilizer 100 is sealed to the through hole. The inlet end of the flame stabilizer 100 is located outside the first feeding pipe 221, and the outlet end of the flame stabilizer 100 passes through the through hole and extends into the first flow path 215 inside the first feeding pipe 221. The housing 12 of the flame stabilizer 100 is spaced apart from the inner peripheral wall of the first feeding pipe 221 so that the coal powder gas flow in the first flow path 215 passes between the housing 12 of the flame stabilizer 100 and the inner peripheral wall of the first feeding pipe 221.

[0078] When the coal-fired power unit combustion stabilization device of this invention is working, the first gas flow is burned in the combustion stabilizer 100 to form a primary flame and a high-temperature combustion zone.

[0079] Then, the primary flame ejected from the burner outlet 125 enters the first flow path 215. At this time, the primary flame first mixes with the second airflow conveyed in the first feed pipe 221. The coal powder carried by the second airflow is preheated by the primary flame ejected from the burner 100 and quickly ignites after mixing with the high-temperature flame ejected from the burner 100. It is then subjected to secondary preheating and forms a secondary flame and a high-temperature zone in the combustion chamber.

[0080] Next, the secondary flame continues to flow to the right. At this time, the second feed pipe 222 delivers the third gas flow to the combustion tube assembly 21 and splits it into the third sub-gas flow and the fourth sub-gas flow. The third sub-gas flow enters the combustion chamber from the second flow path 213 and then meets the secondary flame. At this time, the third sub-gas flow directly mixes and preheats with the secondary flame from the upstream, causing the third sub-gas flow to ignite quickly and be preheated by the third stage, forming a tertiary flame and a high-temperature zone.

[0081] Finally, the fourth sub-gas flow passes through the third flow path 214 and enters the combustion chamber, where it mixes and preheats with the third-stage flame from upstream, causing the fourth sub-gas flow to ignite rapidly and be preheated by the fourth stage, forming the fourth-stage flame and high-temperature zone.

[0082] In operation, the coal-fired power unit combustion stabilization device of this invention utilizes the combustion stabilizer 100 to perform primary combustion of pulverized coal. The first flow path 215, the second flow path 213, and the third flow path 214 deliver pulverized coal fuel to the combustion chamber to mix with the upstream flame, thereby forming multiple high-temperature combustion zones within the device. This allows the pulverized coal to burn sequentially, ensuring complete combustion and improving fuel combustion efficiency. Furthermore, due to the presence of multiple high-temperature zones, the overall temperature distribution inside the multi-stage preheating burner 200 is more uniform, which helps reduce the formation of thermal NOx and improves environmental protection.

[0083] Therefore, the coal-fired power unit combustion stabilization device of the present invention has advantages such as good combustion effect and good environmental protection effect.

[0084] In some embodiments, such as Figure 2 As shown, the pulverized coal pipe assembly 11 includes a first inlet 1111, a first outlet 115, and a second outlet 116. The first inlet 1111, the first outlet 115, and the second outlet 116 are all provided on the pulverized coal pipe assembly 11 and are arranged sequentially and at intervals along the first sub-direction. The first inlet 1111 and the first outlet 115 are connected through a first channel 117, and the first inlet 1111 and the second outlet 116 are connected through a second channel 118. The openings of the first outlet 115 and the second outlet 116 are both set towards the inlet end of the pulverized coal pipe assembly 11.

[0085] For example, the pulverized coal pipe assembly 11 is provided with a first inlet 1111, a first outlet 115, and a second outlet 116, which are arranged sequentially in the left-right direction. The first inlet 1111 is located on the left side of the pulverized coal pipe assembly 11 and outside the housing 12. The first inlet 1111 is connected to the first outlet 115 and also to the second outlet 116. The first outlet 115 and the second outlet 116 are both located inside the housing 12 and are connected to the cavity.

[0086] The openings of the first outlet 115 and the second outlet 116 both face to the left, so that the initial direction of the first sub-airflow and the second sub-airflow entering the cavity is both to the left, so as to form a high-temperature recirculation zone with the secondary air.

[0087] In some embodiments, such as Figure 2 As shown, the pulverized coal pipe assembly 11 includes a first pipe 111 and a second pipe 112. The inlet end of the first pipe 111 is provided with a first inlet 1111. The second pipe 112 and the concentrator 1112 are both disposed inside the first pipe 111. The concentrator 1112 and the second pipe 112 are arranged sequentially and at intervals in a first sub-direction. The inner peripheral wall of the first pipe 111 and the outer peripheral wall of the second pipe 112 define a first sub-channel. The inner peripheral wall of the second pipe 112 defines a second channel 118.

[0088] For example, the first pipe 111 extends in a left-right direction, with its inlet end being the left end and its outlet end being the right end. The left end of the first pipe 111 is open to form the first inlet 1111. The second pipe 112 is located inside the first pipe 111, and the condenser 1112 is located to the left of the second pipe 112 and spaced apart from it. After passing through the condenser 1112, the primary air pulverized coal gas flow is split into a first sub-flow and a second sub-flow. The inner peripheral wall of the first pipe 111 and the outer peripheral wall of the second pipe 112 are spaced apart to form a first sub-channel, and the inner peripheral wall of the second pipe 112 defines a second channel 118. The first outlet 115 is located to the left of the second outlet 116, so that when the first and second sub-flows enter the cavity, the first sub-flow is to the left of the second sub-flow. Thus, by spaced apart, the first sub-channel and the second channel 118 are defined, facilitating the passage of the pulverized coal gas flow.

[0089] Optionally, the left end of the first tube 111 extends out of the housing 12 to the left, and the concentrate 1112 is located at the part of the first tube 111 that extends out of the housing 12, so as to facilitate the replacement of the concentrate 1112.

[0090] In some embodiments, such as Figure 2As shown, the pulverized coal pipe assembly 11 also includes a first return element 113 and a second return element 114. The first return element 113 is sleeved on the outer periphery of the second pipe 112 and connected to the outlet end of the second pipe 112. The outlet end of the first pipe 111 extends between the first return element 113 and the second pipe 112, so that the inner peripheral wall of the first return element 113 and the outer peripheral wall of the first pipe 111 define a return channel 119 that communicates with the first sub-channel, and the opening of the return channel 119 faces the inlet end of the first pipe 111 to form a first outlet 115.

[0091] In the first sub-direction, the first return element 113 and the second return element 114 are arranged sequentially and at intervals, and a part of the second return element 114 is sleeved on the outer periphery of the first return element 113 to form a second outlet 116.

[0092] For example, the outlet end of the second pipe 112 is the right end of the second pipe 112. The first return member 113 is connected to the right end of the second pipe 112 and sleeved on the outer periphery of the second pipe 112. The outlet end of the first pipe 111 is the right end of the first pipe 111. The right end of the first pipe 111 is located between the first return member 113 and the second pipe 112. The outer periphery of the first pipe 111 and the inner periphery of the first return member 113 are spaced apart to form a return channel 119. The right end face of the first pipe 111 is spaced apart from the right end of the first return section, so that the return channel 119 and the first sub-channel can be connected. The opening of the return channel 119 faces to the left to form the first outlet 115.

[0093] The second return element 114 is located on the right side of the first return element 113. A portion of the second return element 114 is sleeved on the outer periphery of the first return element 113 so that a second outlet 116 with an opening facing to the left is formed between the inner peripheral wall of the second return element 114 and the outer peripheral wall of the first return element 113.

[0094] Therefore, the first sub-gas flow, after entering the first sub-channel, is blocked by the first return element 113 and deflected into the return channel 119, and then discharged from the first outlet 115. The second sub-gas flow, after entering the second channel 118, is blocked by the second return element 114 and deflected, and then discharged from the second outlet 116. The burner stabilizer 100 of the coal-fired power unit combustion stabilization device of this embodiment utilizes the first return element 113 and the second return element 114 to ensure that the initial flow direction of both the first and second sub-gas flows into the cavity is to the left, thereby facilitating the formation of a high-temperature combustion zone and improving the stability of the burner stabilizer 100.

[0095] Optionally, such as Figure 2As shown, the first return component 113 includes a first cylindrical part and a first end. The first cylindrical part is sleeved on the outer periphery of the first tube 111, and the first end is used to connect the first cylindrical part and the second tube 112. In the first direction, the first end is spaced apart from the end face of the outlet end of the first tube 111 so that the first sub-channel and the return channel 119 are connected to form the first channel 117.

[0096] For example, the first end is an annular plate-shaped piece, the inner peripheral wall of the first end is connected to the second pipe 112, and the outer peripheral wall of the first end is connected to the first cylindrical part, which extends from the left side of the first end to the left. The outlet end of the first pipe 111 is the right end of the first pipe 111, and the right end of the first pipe 111 is spaced apart from the first end so that the first sub-channel and the return channel 119 can be connected, thereby forming the first channel 117.

[0097] Therefore, the first return element 113 of the combustion stabilizer 100 of the coal-fired power unit combustion stabilization device in this embodiment of the invention has a simple structure and is easy to process.

[0098] Optionally, such as Figure 2 As shown, the second return member 114 includes a second end and a second cylindrical portion. The second end and the first end are spaced apart in a first direction. The second cylindrical portion extends from the surface of the second end toward the direction where the first end is located. The second cylindrical portion is sleeved on the outer peripheral side of the first cylindrical portion so that a second outlet 116 with an opening facing the inlet end of the pulverized coal pipe assembly 11 is formed between the inner peripheral wall of the second cylindrical portion and the outer peripheral wall of the first cylindrical portion.

[0099] For example, the second end is a circular plate-shaped piece, the second cylindrical part extends from the left side of the second end to the left and is fitted onto the outer peripheral wall of the first cylindrical part, the first cylindrical part and the second cylindrical part are spaced apart to form a second outlet 116, the opening of the second outlet 116 facing the left side.

[0100] Therefore, the first return element 113 of the combustion stabilizer 100 of the coal-fired power unit combustion stabilization device in this embodiment of the invention has a simple structure and is easy to process.

[0101] In some embodiments, such as Figure 2 As shown, the housing 12 includes a first segment 121, a second segment 122, a third segment 123 and a fourth segment 124 connected in sequence in a first direction. The first segment 121 and the third segment 123 are both cylindrical. The cross-sectional area of ​​the second segment 122 gradually increases along the first sub-direction, and the cross-sectional area of ​​the fourth segment 124 gradually decreases along the first sub-direction. The first outlet 115 is located in the second segment 122, and the second outlet 116 is located in the third segment 123.

[0102] For example, the first section 121, the second section 122, the third section 123, and the fourth section 124 are arranged sequentially from left to right. The secondary air duct 13 is located on the outer periphery of the first section 121. The first section 121 and the third section 123 are both cylindrical; in other words, the cross-sectional areas of the first section 121 and the third section 123 remain constant. The cross-sectional area of ​​the second section 122 gradually increases from left to right, and the cross-sectional area of ​​the fourth section 124 gradually decreases from left to right. The right end of the fourth section 124 is provided with a flame stabilizer outlet 125. The fourth section 124 can concentrate the flame in the flame stabilizer 100 and increase the flame velocity.

[0103] In the combustion stabilizer 100 of the coal-fired power unit combustion stabilizer of the present invention, since the cross-sectional area of ​​the second section 122 gradually increases from left to right, the flow velocity of the secondary air decreases and the static pressure gradually increases during the process of the secondary air flowing through the second section 122, so as to form a high recirculation zone.

[0104] In some embodiments, such as Figure 2 As shown, the concentrator 1112 is annular and the inner peripheral wall of the concentrator 1112 defines a concentration adjustment channel. The outer peripheral wall of the concentrator 1112 is in contact with the inner peripheral wall of the first tube 111. The concentrator 1112 includes a tapered section 11121 and a widening section 11122 arranged sequentially along the first sub-direction. The cross-sectional area of ​​the tapered section 11121 gradually increases along the first sub-direction, and the cross-sectional area of ​​the widening section 11122 gradually decreases along the first sub-direction, so that the cross-sectional area of ​​the concentration adjustment channel first gradually decreases and then gradually increases along the first sub-direction.

[0105] For example, the concentrator 1112 is an annular component, with a concentration regulating channel in the middle. The primary air pulverized coal gas flow can pass through the concentration regulating channel. The outer peripheral wall of the concentrator 1112 is fitted to the inner peripheral wall of the first pipe 111, so that the primary air pulverized coal gas flow can only pass through the concentration regulating channel. The tapering section 11121 is located to the left of the expanding section 11122, adjacent to the first outlet 115. The cross-section of the tapering section 11121 is annular, and the cross-sectional area of ​​the tapering section 11121 gradually increases from left to right, so that the cross-sectional area of ​​the concentration regulating channel defined by the inner peripheral wall of the tapering section 11121 gradually decreases from left to right.

[0106] The cross-section of the expanding section 11122 is also annular, and the cross-sectional area of ​​the expanding section 11122 gradually decreases from left to right, so that the cross-sectional area of ​​the concentration regulation channel defined by the inner peripheral wall of the expanding section 11122 gradually increases from left to right.

[0107] When the stabilizer 100 of the coal-fired power unit stabilization device of this embodiment is working, the primary air-coal powder gas flow first encounters the condenser 1112. During the collision of the coal powder particles in the primary air-coal powder gas flow with the condenser 1112, in the converging section 11121, the primary air-coal powder gas flow gradually gathers near the center line of the first pipe 111, so that the coal powder concentration near the center line of the first pipe 111 gradually increases. In the expanding section 11122, the primary air-coal powder gas flow gradually diffuses near the pipe wall of the first pipe 111. Since the distance between the condenser 1112 and the second pipe 112 is short, even if the primary air-coal powder gas flow diffuses near the pipe wall of the first pipe 111, there is not enough time for the coal powder concentration near the pipe wall of the first pipe 111 to reach the coal powder concentration near the center line of the first pipe 111.

[0108] Therefore, when the primary air pulverized coal gas flows through the concentration adjustment channel, it is subjected to inertial separation, resulting in concentration separation. This forms a first sub-gas flow with a lower pulverized coal concentration near the inner wall of the first pipe 111, and a second sub-gas flow with a higher pulverized coal concentration near the centerline of the first pipe 111. The first sub-gas flow then enters the first channel 117 outside the second pipe 112, and the second sub-gas flow enters the second channel 118 inside the second pipe 112.

[0109] Optionally, such as Figure 2 As shown, the second tube 112 and the first return component 113 are integrally formed. Therefore, the second tube 112 and the first return component 113 are easy to process.

[0110] In some embodiments, such as Figure 1 As shown, the combustion tube assembly 21 includes an inner tube 211, which has a cavity to form a combustion chamber. The inner tube 211 includes a first combustion section 2111 and a second combustion section 2112. The first combustion section 2111 and the second combustion section 2112 are arranged sequentially and connected in a first sub-direction. The outlet end of the first combustion section 2111 extends into the inlet end of the second combustion section 2112, so that the outer peripheral wall of the first combustion section 2111 and the inner peripheral wall of the second combustion section 2112 define a second flow path 213.

[0111] For example, the inner tube 211 includes a first combustion section 2111 and a second combustion section 2112. The first combustion section 2111 is located to the left of the second combustion section 2112. The combustion chamber includes a first combustion chamber and a second combustion chamber. The first combustion chamber is located in the first combustion section 2111 and the second combustion chamber is located in the second combustion section 2112.

[0112] The left end of the first combustion section 2111 is connected to the first flow path 215, and the right end of the first combustion section 2111 can extend into the second combustion section 2112. The outer peripheral wall of the first combustion section 2111 and the inner peripheral wall of the second combustion section 2112 are spaced apart to define the second flow path 213.

[0113] In some embodiments, such as Figure 1 As shown, the combustion tube assembly 21 also includes an outer tube 212, which is sleeved on the outside of the inner tube 211 and the inner peripheral wall of the outer tube 212 is spaced apart from the outer peripheral wall of the inner tube 211. The outer tube 212 includes a rectifier section 2121 and a guide section 2122 arranged sequentially along the first sub-direction. The inlet end of the rectifier section 2121 is sealed to the inlet end of the first combustion section 2111. The inner peripheral wall of the guide section 2122 and the outer peripheral wall of the second combustion section 2112 define a third flow path 214.

[0114] For example, the outer tube 212 extends in the left and right direction, the rectifier section 2121 is located on the left side of the guide section 2122, and the guide section 2122 and the second combustion section 2112 are arranged at intervals so that the inner peripheral wall of the guide section 2122 and the outer peripheral wall of the second combustion section 2112 define a third flow path 214.

[0115] It should be noted that the left side of the rectifying section 2121 is sealed to the left side of the first combustion section 2111, and the right end of the rectifying section 2121 is sealed to the left end of the guide section 2122. The rectifying section 2121 is fitted onto the outside of the first combustion section 2111 to form a rectifying cavity between the outer peripheral wall of the first combustion section 2111 and the inner peripheral wall of the rectifying section 2121. The left end of the second flow path 213 is connected to the rectifying cavity, the right end of the second flow path 213 is connected to the inlet end of the second combustion chamber, the left end of the third flow path 214 is connected to the rectifying cavity, and the right end of the third flow path 214 is connected to the outlet end of the second combustion chamber.

[0116] The second flow path 213 and the third flow path 214 are both located in the guide section 2122. The right end of the first combustion section 2111 extends to the right into the guide section 2122 so as to form a flow channel between the rectifying section 2121 and the first combustion section 2111, thereby facilitating the airflow in the rectifying cavity to enter the second flow path 213 and the third flow path 214 along the flow channel.

[0117] Therefore, the burner 200 of the coal-fired power unit stable combustion device of the present invention defines the rectifier cavity by setting the rectifier section 2121, so that the coal powder airflow in the second feed pipe 222 can be adjusted in the rectifier cavity to form a stable flow before entering the combustion chamber, thereby facilitating the stable combustion of the coal powder airflow in the combustion chamber and improving the stability of the multi-stage preheating burner 200.

[0118] In some embodiments, such as Figure 1 As shown, the first feeding pipe 221 includes a first transition section 2212 and a first feeding section 2211. The first transition section 2212 is connected to the first combustion section 2111. The first transition section 2212 extends along a first direction, and the cross-sectional area of ​​the first transition section 2212 gradually decreases along the first sub-direction.

[0119] The inlet end of the first feeding section 2211 extends along the second direction, which is orthogonal to the first direction. The outlet end of the first feeding section 2211 extends along the first direction. The first feeding section 2211 is connected to the first transition section 2212, and the first feeding section 2211 and the first transition section 2212 are connected to form the first flow path 215.

[0120] For example, for ease of description, the following will use... Figure 1 The vertical direction is the second direction.

[0121] The first transition section 2212 extends in the left-right direction, and its right end is connected to the first combustion section 2111. The cross-sectional area of ​​the first transition section 2212 gradually decreases from left to right. Thus, the first transition section 2212 can be easily adapted to the first combustion section 2111 for connection.

[0122] The inlet end of the first feeding section 2211 faces downwards, and the outlet end of the first feeding section 2211 faces to the right; in other words, the centerline of the first feeding section 2211 is arc-shaped. The pulverized coal gas flow passes sequentially through the first feeding section 2211 and the first transition section 2212 before entering the first combustion section 2111. The cavities within the first feeding section 2211 and the first transition section 2212 are connected to form the first flow path 215.

[0123] In some embodiments, such as Figure 1 As shown, the second feeding section includes a second transition section 2221, which is connected to the rectifier section 2121, and the cross-sectional area of ​​the second transition section 2221 gradually increases along the second direction.

[0124] For example, the second transition section 2221 is located below the rectifying section 2121, and the cross-sectional area of ​​the second transition section 2221 gradually increases from bottom to top, thereby facilitating the improvement of the efficiency of the pulverized coal gas flow into the rectifying section 2121.

[0125] In some embodiments, such as Figure 7 As shown, the multi-stage preheating burner 200 also includes an air supply pipe. The multi-stage preheating burner 200 is a four-corner tangent circular DC multi-stage preheating burner 200, and the air supply pipe is sleeved on the outer periphery of the guide section 2122.

[0126] For example, when the multi-stage preheating burner 200 is a direct-flow multi-stage preheating burner 200 with tangent corners, an air supply pipe can be arranged on the outer periphery of the guide section 2122. The air supply pipe is equipped with a direct-flow first nozzle 231 to provide an oxygen-containing flow into the burner, which is used to supply the oxygen required for subsequent combustion of pulverized coal in stages. This promotes the complete combustion of pulverized coal and achieves staged combustion of air to reduce NOx generation. In this case, the cross-sectional shape of the first combustion section 2111, the second combustion section 2112, and the guide section 2122, which are perpendicular to the axial direction of the multi-stage preheating burner 200, are all rectangular.

[0127] For a DC multi-stage preheating burner 200 with tangent corners, the oxygen-containing flow can be arranged at certain intervals around the multi-stage preheating burner 200 and injected directly, that is, the nozzle is a cylindrical structure with a circular or rectangular cross-section.

[0128] In some embodiments, such as Figure 8 As shown, the multi-stage preheating burner 200 also includes an air supply pipe. The multi-stage preheating burner 200 is a wall-mounted counter-current swirl multi-stage preheating burner 200. The air supply pipe includes a first pipe 111 and a second pipe 112. The first pipe 111 is sleeved on the outer periphery of the guide section 2122, and the second pipe 112 is sleeved on the outer periphery of the second pipe 112.

[0129] For example, when the multi-stage preheating burner 200 is a wall-mounted, counter-flow swirl multi-stage preheating burner 200, an air supply duct can be arranged outside the guide section 2122. The air supply duct includes an annular third nozzle 233 and a second nozzle 232. The second nozzle 232 is located on the outer periphery of the third nozzle 233 to provide oxygen-containing flow to the multi-stage preheating burner 200. Swirl blades 234 are uniformly arranged circumferentially inside the third nozzle 233 and the second nozzle 232 to guide the direct current airflow into a high-speed rotating jet at the outlet. In this case, the cross-sectional shapes of the first combustion section 2111, the second combustion section 2112, and the guide section 2122, which are perpendicular to the axial direction of the multi-stage preheating burner 200, are all circular.

[0130] For the wall-mounted counter-current swirl multi-stage preheating burner 200, this tertiary air can be injected in two annular swirls around the multi-stage preheating burner 200, and two annular nozzles, inner and outer, are provided. The outlet swirl intensity of the airflow in the two nozzles can be adjusted by adjusting the blade angle 234. While realizing air classification, the oxygen-containing airflow injected by the swirl will also help to form a low-pressure zone at the outlet of the multi-stage preheating burner 200, forming a high-temperature flue gas recirculation, promoting further combustion and stable ignition of pulverized coal.

[0131] The following is based on the appendix Figure 1-8 A specific embodiment of the present invention is described below.

[0132] First, by adjusting the concentrator, the coal powder concentrations of the first, second, and third airflows are reduced sequentially.

[0133] Secondly, the first airflow is introduced into the pulverized coal pipe assembly 11 from the first inlet 1111, so that the first airflow meets the concentrator 1112. During the collision of the pulverized coal particles in the first airflow with the concentrator 1112, they are subjected to inertial separation, which will cause the first airflow to be separated into concentrated and diluted states. This causes the pulverized coal to accumulate near the center line of the first pipe 111, thereby forming a first sub-airflow with a lower pulverized coal concentration near the inner wall of the first pipe 111, and a second sub-airflow with a higher pulverized coal concentration near the center line of the first pipe 111.

[0134] Then, the first sub-airflow enters the first channel 117 and, under the action of the first return flow member 113, enters the return flow channel 119, causing the first sub-airflow to flow into the second section 122 in a right-to-left direction. The second sub-airflow enters the second channel 118 and, under the action of the second return flow member 114, causes the second sub-airflow to flow into the third section 123 in a right-to-left direction, and gradually flows to the left into the second section 122.

[0135] Simultaneously, secondary air is injected at high speed into the cavity along the secondary air duct 13, forming a high-speed rotating airflow within the first section 121. This airflow then flows into the area near the inner wall of the second section 122. Due to the large tangential velocity of the secondary air at this point, a low-pressure zone is formed in the central region of the secondary airflow during its high-speed rotating flow. Furthermore, as the cross-sectional area of ​​the second section 122 gradually increases from left to right, the flow velocity of the secondary air decreases while the static pressure gradually increases as it flows through the second section 122.

[0136] In summary, a low-pressure area forms in the central region of the secondary wind, the flow velocity of the secondary wind decreases and the static pressure gradually increases. Under the influence of these two factors, as the secondary wind gradually flows to the right, some of the secondary wind will flow into the low-pressure area, thus forming a high-speed recirculation zone in the second segment 122 and the third segment 123.

[0137] Because the second outlet 116 is located near the high-speed recirculation zone, the second sub-gas flow is injected near the high-speed recirculation zone, making it easier for the second sub-gas flow to be entrained into the high-speed recirculation zone during its flow. The second sub-gas flow swirls and burns in the high-speed recirculation zone, releasing heat and forming a dense phase high-temperature recirculation zone. This will help promote the rapid heating and ignition of the second sub-gas flow and release more heat, forming a dense phase high-temperature recirculation zone.

[0138] At the same time, the first sub-flow is injected at a certain distance to the left of the second sub-flow. The first sub-flow is blocked and carried by the secondary wind in the swirling state, thus changing direction. The first sub-flow enters the dense phase high-temperature recirculation zone between the secondary wind in the swirling state and the second sub-flow.

[0139] In this process, although the coal powder concentration in the first sub-gas stream is low and not easily ignited, on the one hand, the low concentration of coal powder in the first sub-gas stream is subjected to convective and radiative heat transfer in the high-temperature reflux zone, which can promote the heating and ignition of the first sub-gas stream. On the other hand, the first outlet 115 is located to the left of the second outlet 116, which allows the first sub-gas stream to have a relatively longer residence time in the shell 12 compared to the second sub-gas stream. These two aspects will jointly promote the ignition and burnout effect of the first sub-gas stream. At this time, the first sub-gas stream is preheated, rapidly heats up and ignites, and releases a large amount of heat, forming a light-phase high-temperature reflux zone.

[0140] Meanwhile, since the second sub-gas flow is injected at a certain distance from the first sub-gas flow, it helps to delay the mixing of rich and lean gas flows. This promotes overall burnout and enhances the rich and lean combustion effect of pulverized coal, thereby reducing NOx formation.

[0141] Then, the airflow in the dense phase high-temperature reflux zone and the light phase high-temperature reflux zone together form a first-stage flame. After being gathered and accelerated by the fourth stage 124, the first-stage flame is ejected at high speed from the burner outlet 125.

[0142] After passing through the first feeding section 2211 and the first transition section 2212, the second airflow enters the first combustion chamber. That is, the second airflow enters the first combustion chamber from the first flow path 215, and then mixes with the primary flame ejected from the burner outlet 125 in the first transition section 2212 and the first combustion chamber. The pulverized coal carried by the second airflow is preheated by the primary flame ejected from the burner 100, and after mixing with the high-temperature flame ejected from the burner 100, it is quickly ignited and subjected to secondary preheating to form a secondary flame and a high-temperature zone.

[0143] Meanwhile, the third airflow enters the rectifying section 2121 after passing through the second transition section 2221. After being stabilized by the rectifying cavity, the third airflow flows to the right and splits into a third sub-airflow and a fourth sub-airflow. The third sub-airflow enters the second combustion tube from the second flow path 213, and the fourth sub-airflow enters the second combustion tube from the third flow path 214.

[0144] After passing through the second flow path 213, the third sub-gas flow flows near the inner peripheral wall of the second combustion tube. At this time, the third sub-gas flow directly mixes and preheats with the secondary flame from the upstream, causing the third sub-gas flow to ignite rapidly and be preheated by the third stage, forming the third stage flame and high-temperature zone.

[0145] After passing through the third flow path 214, the fourth sub-flow directly mixes and preheats with the third-stage flame from upstream, causing the fourth sub-flow to ignite rapidly and be preheated by the fourth stage, forming the fourth-stage flame and high-temperature zone.

[0146] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0147] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0148] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0149] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0150] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0151] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A combustion stabilization device for coal-fired power units, characterized in that, include: A burner and a flame stabilizer, wherein the flame stabilizer is connected to the burner and extends along a first direction, the first direction including a first sub-direction and a second sub-direction opposite to the first sub-direction, and the direction from the inlet end of the flame stabilizer to the outlet end of the flame stabilizer is the first sub-direction; The flame stabilizer includes: A housing, the housing including a cavity; A pulverized coal pipe assembly, at least a portion of which is disposed within the cavity, wherein the outer peripheral surface of the pulverized coal pipe assembly is sealed to the housing; the pulverized coal pipe assembly is provided with a first channel and a second channel, which are spaced apart within the pulverized coal pipe assembly, and both the first channel and the second channel communicate with the cavity, wherein the outlet of the first channel is adjacent to the inlet end of the pulverized coal pipe assembly relative to the outlet of the second channel; A condenser is disposed inside the pulverized coal pipe assembly. The condenser can split the primary air pulverized coal gas flow entering the pulverized coal pipe assembly into a first sub-gas flow and a second sub-gas flow. The pulverized coal concentration of the first sub-gas flow is less than that of the second sub-gas flow. The first channel is used for the passage of the first sub-gas flow, and the second channel is used for the passage of the second sub-gas flow. A secondary air duct, which is connected to the cavity; The burner includes: A feeding tube assembly, comprising a first feeding tube and a second feeding tube arranged sequentially and at intervals in the first sub-direction, wherein the first feeding tube is provided with a first flow path. A combustion tube assembly is provided, wherein a combustion chamber is provided within the combustion tube assembly, and a feeding pipe assembly is connected to the combustion tube assembly. The combustion tube assembly extends along a first direction and is provided with a second flow path and a third flow path. The first flow path, the second flow path, and the third flow path are all connected to the combustion chamber. The first flow path, the second flow path, and the third flow path are spaced apart in the first direction. The second feeding pipe is connected to both the second flow path and the third flow path. The outlet end of the combustion tube assembly is adapted to be connected to a combustion furnace. The outlet end of the flame stabilizer extends through the side wall of the first feeding pipe into the first flow path so as to communicate with the combustion chamber.

2. The coal-fired power unit combustion stabilization device according to claim 1, characterized in that, The pulverized coal pipe assembly includes a first inlet, a first outlet, and a second outlet. The first inlet, the first outlet, and the second outlet are all located on the pulverized coal pipe assembly and are arranged sequentially and at intervals along a first sub-direction. The first inlet and the first outlet are connected through the first channel, and the first inlet and the second outlet are connected through the second channel. The openings of the first outlet and the second outlet are both oriented towards the inlet end of the pulverized coal pipe assembly.

3. The coal-fired power unit combustion stabilization device according to claim 2, characterized in that, The pulverized coal pipe assembly includes: The first tube has a first inlet at its inlet end; The second tube and the condenser are both disposed inside the first tube. The condenser and the second tube are arranged sequentially and at intervals in the first sub-direction. The inner peripheral wall of the first tube and the outer peripheral wall of the second tube define a first sub-channel, and the inner peripheral wall of the second tube defines a second channel.

4. The coal-fired power unit combustion stabilization device according to claim 3, characterized in that, The pulverized coal pipe assembly also includes: The first return element is sleeved on the outer periphery of the second tube and connected to the outlet end of the second tube. The outlet end of the first tube extends between the first return element and the second tube, so that the inner peripheral wall of the first return element and the outer peripheral wall of the first tube define a return channel communicating with the first sub-channel, and the opening of the return channel faces the inlet end of the first tube to form the first outlet. The second return element is arranged sequentially and at intervals in the first sub-direction, with a portion of the second return element sleeved on the outer periphery of the first return element to form the second outlet.

5. The coal-fired power unit combustion stabilization device according to any one of claims 2-4, characterized in that, The housing includes a first segment, a second segment, a third segment, and a fourth segment connected sequentially in the first direction. The first segment and the third segment are both cylindrical. The cross-sectional area of ​​the second segment gradually increases along the first sub-direction, and the cross-sectional area of ​​the fourth segment gradually decreases along the first sub-direction. The first outlet is located in the second segment, and the second outlet is located in the third segment.

6. The coal-fired power unit combustion stabilization device according to claim 3, characterized in that, The concentrator is annular, and its inner peripheral wall defines a concentration adjustment channel. The outer peripheral wall of the concentrator is in contact with the inner peripheral wall of the first tube. The concentrator includes a tapering section and a expanding section arranged sequentially along the first sub-direction. The cross-sectional area of ​​the tapering section gradually increases along the first sub-direction, and the cross-sectional area of ​​the expanding section gradually decreases along the first sub-direction, so that the cross-sectional area of ​​the concentration adjustment channel first gradually decreases and then gradually increases along the first sub-direction.

7. The coal-fired power unit combustion stabilization device according to claim 1, characterized in that, The combustion tube assembly includes an inner tube with a cavity to form the combustion chamber. The inner tube includes a first combustion section and a second combustion section, which are arranged sequentially and connected in the first sub-direction. The outlet end of the first combustion section extends into the inlet end of the second combustion section, so that the outer peripheral wall of the first combustion section and the inner peripheral wall of the second combustion section define the second flow path.

8. The coal-fired power unit combustion stabilization device according to claim 7, characterized in that, The combustion tube assembly further includes an outer tube, which is sleeved outside the inner tube and the inner peripheral wall of the outer tube is spaced apart from the outer peripheral wall of the inner tube. The outer tube includes a rectifier section and a guide section arranged sequentially along the first sub-direction. The inlet end of the rectifier section is sealed to the inlet end of the first combustion section, and the inner peripheral wall of the guide section and the outer peripheral wall of the second combustion section define a third flow path.

9. The coal-fired power unit combustion stabilization device according to claim 8, characterized in that, The first feed tube includes: A first transition section is connected to the first combustion section, the first transition section extends along the first direction, and the cross-sectional area of ​​the first transition section gradually decreases along the first sub-direction; The first feeding section has an inlet end that extends along a second direction, which is orthogonal to the first direction, and an outlet end that extends along the first direction. The first feeding section is connected to the first transition section, and the first feeding section and the first transition section are connected to form the first flow path.

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