Pulverized Coal Stable Combustion Burner and Operation Method

Abstract

The present invention discloses a pulverized coal stable combustion burner, which comprises a body, a pulverized coal pipe and a coal discharging member. One end of the body has a chamber, and one end of the pulverized coal pipe extends into the chamber. The pulverized coal pipe has a first flow channel and a second flow channel, and the second flow channel is sleeved outside the first flow channel. Both the first flow channel and the second flow channel are communicated with the chamber, and pulverized coal can be introduced into the chamber through the first flow channel and the second flow channel. The coal discharging member is arranged at one end of the pulverized coal pipe. The coal discharging member has a first channel, a second channel and a coal discharging port. One end of the first channel is communicated with the first flow channel, one end of the second channel is communicated with the second flow channel, and the other ends of the first channel and the second channel are both communicated with the coal discharging port. There is an included angle a between the flowing direction of the pulverized coal flowing out through the first channel and the flowing direction of the pulverized coal flowing out through the second channel, and the size of the included angle a is adjustable. The pulverized coal stable combustion burner according to the embodiment of the present invention is applicable to different coal types, has strong adaptability and stable combustion.

Description

Technical Field

[0001] The present invention relates to the technical field of flame stabilizers, and in particular, to a pulverized coal flame stabilizer and an operation method thereof. Background Art

[0002] The deep peak shaving operation of coal-fired power units is an important measure to promote the construction of a new energy system. In this context, there is an urgent need to develop low-load stable combustion technologies with good operation economy and reliability. Compared with the commonly used plasma ignition, oil injection for combustion assistance and other ignition and stable combustion technologies, the technology of using a small amount of pulverized coal to burn first to ignite and stabilize the main pulverized coal air flow (abbreviated as the "coal igniting coal" technology) is considered to have obvious advantages in terms of economy and reliability.

[0003] In related technologies, the reverse injection combustion technology is adapted to the technical idea of "coal igniting coal", that is, a high-temperature recirculation zone is constructed inside the combustion chamber to strengthen the rapid temperature rise and ignition of pulverized coal and stable combustion. However, when using different coal types in the reverse injection combustion technology, due to different fuel characteristics, the operation of the flame stabilizer is prone to fluctuations and the reliability is low. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems in the related technologies to some extent.

[0005] Therefore, an embodiment of the present invention provides a pulverized coal flame stabilizer and an operation method thereof.

[0006] The pulverized coal flame stabilizer according to the embodiment of the present invention includes:

[0007] A body, one end of the body has a chamber, and a recirculation zone is provided inside the chamber;

[0008] A pulverized coal pipe, one end of the pulverized coal pipe extends into the chamber, the pulverized coal pipe has a first flow channel and a second flow channel, the second flow channel is sleeved outside the first flow channel, both the first flow channel and the second flow channel are communicated with the chamber, and pulverized coal can be introduced into the chamber through the first flow channel and the second flow channel;

[0009] A coal discharging member, the coal discharging member is arranged at one end of the pulverized coal pipe, the coal discharging member has a first channel, a second channel and a coal discharging port, one end of the first channel is communicated with the first flow channel, one end of the second channel is communicated with the second flow channel, the other ends of the first channel and the second channel are both communicated with the coal discharging port, the coal discharging port is located in the recirculation zone and the coal discharging port is opened towards the other end of the pulverized coal pipe, and the pulverized coal in the first flow channel and the pulverized coal in the second flow channel flow into the recirculation zone through the coal discharging port,

[0010] There is an included angle α between the flow direction of the pulverized coal flowing out through the first channel and the flow direction of the pulverized coal flowing out through the second channel. By adjusting the amount of pulverized coal in the first flow channel and the amount of pulverized coal in the second flow channel, the flow direction of the pulverized coal flowing out through the first channel and the flow direction of the pulverized coal flowing out through the second channel are changed, so that the magnitude of the included angle α is adjustable.

[0011] In the pulverized coal stable combustion device according to the embodiment of the present invention, by providing the first flow channel and the second flow channel, pulverized coal of different coal types can be separately stored. The pulverized coal in the first channel and the pulverized coal in the second channel meet near the coal outlet, and then converge into a stream of pulverized coal and jet out from the coal outlet. During this process, by adjusting the amount of pulverized coal in the first flow channel and the amount of pulverized coal in the second flow channel, the jet momentum ratio of the two pulverized coal airflows at the coal outlet can be adjusted, so as to change the mutual entrainment effect between the two pulverized coal jets, so that the magnitude of the included angle α between the two pulverized coal jets is adjustable.

[0012] When the included angle α increases, the radial velocity component of the pulverized coal jet flowing radially around at the coal outlet increases, and the axial velocity component decreases, so that the velocity attenuation of the pulverized coal jet from one end of the pulverized coal pipe to the other end of the pulverized coal pipe is accelerated. After turning earlier, it flows from the other end of the pulverized coal pipe to one end of the pulverized coal pipe, so as to achieve the purpose of reducing the axial length of the recirculation zone in the chamber. When the included angle α decreases, the radial velocity component of the pulverized coal jet flowing radially around at the coal outlet decreases, and at the same time the axial velocity component increases, so that the velocity attenuation of the pulverized coal jet from one end of the pulverized coal pipe to the other end of the pulverized coal pipe is slowed down. After delaying the turning, it flows from the other end of the pulverized coal pipe to one end of the pulverized coal pipe, so as to achieve the purpose of increasing the axial length of the recirculation zone in the chamber, thereby flexibly constructing the recirculation zone distribution suitable for stable combustion of different coal types, and improving the coal type adaptability of the pulverized coal stable combustion device and the stability during the operation of the pulverized coal stable combustion device.

[0013] In some embodiments, the value range of the included angle α is: 0≤α<90°.

[0014] In some embodiments, the pulverized coal pipe includes:

[0015] A first pulverized coal pipe, one end of the first pulverized coal pipe extends into the chamber, and the first flow channel is formed in the first pulverized coal pipe;

[0016] A second pulverized coal pipe, the second pulverized coal pipe is sleeved outside the first pulverized coal pipe, one end of the second pulverized coal pipe extends into the chamber, one end of the first pulverized coal pipe extends out of one end of the second pulverized coal pipe, and the second flow channel is formed between the inner peripheral surface of the second pulverized coal pipe and the outer peripheral surface of the first pulverized coal pipe.

[0017] In some embodiments, the central axis of the first flow channel is collinear with the central axis of the second flow channel.

[0018] In some embodiments, the coal discharging member includes:

[0019] A protruding portion, one end of the protruding portion is arranged at one end of the second pulverized coal pipe and is arranged around the circumferential direction of the second pulverized coal pipe, and the other end of the protruding portion extends in a first direction away from the second pulverized coal pipe;

[0020] A first guiding portion and an extending portion, one end of the first guiding portion is arranged at one end of the first pulverized coal pipe and is arranged around the circumferential direction of the first pulverized coal pipe, the other end of the first guiding portion extends outward along the circumferential direction of the first pulverized coal pipe, the other end of the first guiding portion is located outside the protruding portion, one end of the extending portion is arranged around the other end of the first guiding portion, the other end of the extending portion extends in the first direction towards the protruding portion, the extending portion is located outside the protruding portion, and the second channel is formed between the outer peripheral surface of the protruding portion and the inner peripheral surfaces of the first guiding portion and the extending portion;

[0021] A second guiding portion, one end of the second guiding portion is connected to the outer peripheral surface of the second pulverized coal pipe, the coal discharging port is formed at one end of the second guiding portion and is opened in the first direction, the second guiding portion has an inner cavity, the protruding portion, the first guiding portion and the extending portion are located in the inner cavity, and the first channel is formed between the outer peripheral surfaces of the first guiding portion and the extending portion and the inner peripheral surface of the second guiding portion.

[0022] In some embodiments, the outer peripheral surface of the protruding portion is an inclined surface extending in the first direction and gradually away from the second pulverized coal pipe from the other end of the protruding portion to one end of the protruding portion.

[0023] In some embodiments, the inner peripheral surface of the extending portion is an inclined surface and is adapted to the outer peripheral surface of the protruding portion, so that an included angle a is formed between the central axis of one end of the second channel adjacent to the coal discharging port and the central axis of the coal discharging port, and the central axis of one end of the first channel adjacent to the coal discharging port is parallel to the central axis of the coal discharging port.

[0024] In some embodiments, the central axes of the protruding portion, the first guiding portion and the second guiding portion are collinear.

[0025] In some embodiments, the pulverized coal stabilizer further includes a branch pipe, the branch pipe is arranged at the other end of the second pulverized coal pipe, the central axis of the branch pipe is orthogonal to the central axis of the second pulverized coal pipe, and the other end of the first pulverized coal pipe extends out of the other end of the second pulverized coal pipe.

[0026] The operation method of the pulverized coal stabilizer according to the embodiment of the present invention includes:

[0027] Coal powder is introduced into the first coal powder pipe, and the coal powder in the first coal powder pipe flows into the first channel and flows out from the coal outlet.

[0028] Coal powder is introduced into the second coal powder pipe, and the coal powder in the second coal powder pipe flows into the second channel and flows out from the coal outlet.

[0029] By adjusting the amount of coal powder introduced into the first coal powder pipe and the amount of coal powder introduced into the second coal powder pipe, the size of the included angle a can be adjusted.

[0030] In the operation method of the coal powder stabilizer according to the embodiment of the present invention, when the included angle a increases, the radial velocity component of the coal powder jet flowing around at the coal outlet increases, and the axial velocity component decreases, so that the overall flow velocity attenuation of the coal powder jet from one end of the coal powder pipe to the other end of the coal powder pipe is accelerated. After early turning, it flows from the other end of the coal powder pipe to one end of the coal powder pipe, so as to achieve the purpose of reducing the axial length of the recirculation zone in the chamber. When the included angle a decreases, the radial velocity component of the coal powder jet flowing around at the coal outlet decreases, and at the same time the axial velocity component increases, so that the overall flow velocity attenuation of the coal powder jet from one end of the coal powder pipe to the other end of the coal powder pipe is slowed down. After delaying turning, it flows from the other end of the coal powder pipe to one end of the coal powder pipe, so as to achieve the purpose of increasing the axial length of the recirculation zone in the chamber, thereby flexibly constructing the recirculation zone distribution suitable for stable combustion of different coal types, improving the coal type adaptability of the coal powder stabilizer, and moreover, the operation process is simple and the adjustment efficiency is high. Description of the Drawings

[0031] Figure 1 is a sectional view of the coal powder stabilizer according to the embodiment of the present invention.

[0032] Figure 2 is a schematic diagram of the coal outlet part of the coal powder stabilizer according to the embodiment of the present invention.

[0033] Reference numerals: 1, body; 11, chamber; 111, recirculation zone; 2, coal powder pipe; 21, first coal powder pipe; 211, first flow channel; 22, second coal powder pipe; 221, second flow channel; 3, coal outlet part; 31, protruding part; 32, first guiding part; 33, extending part; 34, second guiding part; 341, inner cavity; 35, first channel; 36, second channel; 37, coal outlet; 4, branch pipe. Detailed Embodiments

[0034] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0035] As Figure 1-2As shown, the pulverized coal stabilizer of the embodiment of the present invention includes a main body 1, a pulverized coal pipe 2, and a coal discharging member 3. One end of the main body 1 extending in the first direction (such as the left-right direction shown in Figure 1 ), for example, the right end of the main body 1 shown in Figure 1 has a chamber 11, and there is a reflux zone 111 in the chamber 11. As shown in Figure 1 , the length of the reflux zone 111 is L. One end of the pulverized coal pipe 2 (such as the right end of the pulverized coal pipe 2 shown in Figure 1 ) extends into the chamber 11. The pulverized coal pipe 2 has a first flow channel 211 and a second flow channel 221. The second flow channel 221 is sleeved outside the first flow channel 211. Both the first flow channel 211 and the second flow channel 221 are communicated with the chamber 11. Pulverized coal can be introduced into the chamber 11 through the first flow channel 211 and the second flow channel 221.

[0036] The coal discharging member 3 is arranged at the right end of the pulverized coal pipe 2. The coal discharging member 3 has a first channel 35, a second channel 36, and a coal discharging port 37. One end of the first channel 35 is communicated with the first flow channel 211, one end of the second channel 36 is communicated with the second flow channel 221, the other ends of both the first channel 35 and the second channel 36 are communicated with the coal discharging port 37. The coal discharging port 37 is located in the reflux zone 111 and the coal discharging port 37 is opened towards the other end of the pulverized coal pipe 2 (such as the left end of the pulverized coal pipe 2 shown in Figure 1 ). Specifically, the central axis of the coal discharging port 37 extends in the first direction. The pulverized coal in the first flow channel 211 and the pulverized coal in the second flow channel 221 flow into the reflux zone 111 through the coal discharging port 37 to burn in the reflux zone 111, and the temperature in the reflux zone 111 rises. Specifically, the cross-sectional area of the outlet of the second channel 36 is equal to the cross-sectional area of the outlet of the first channel 35.

[0037] There is an included angle a between the flow direction of the pulverized coal flowing out through the first channel 35 and the flow direction of the pulverized coal flowing out through the second channel 36. By adjusting the amount of pulverized coal in the first flow channel 211 and the amount of pulverized coal in the second flow channel 221, the flow direction of the pulverized coal flowing out through the first channel 35 and the flow direction of the pulverized coal flowing out through the second channel 36 can be changed, so that the magnitude of the included angle a is adjustable.

[0038] The pulverized coal stabilizer according to the embodiment of the present invention can store pulverized coal of different coal types separately by providing a first flow channel 211 and a second flow channel 221. The flow direction of the pulverized coal flowing out of the second channel 36 forms an included angle a with the flow direction of the pulverized coal flowing out of the first channel 35. Under the combined action of the second channel 36 and the first channel 35, the pulverized coal airflows flowing through them respectively will meet near the outlets of the second channel 36 and the first channel 35, and then converge into an annular pulverized coal jet and spray out at a high speed. During this process, the flow rates of the pulverized coal airflows in the first flow channel 211 and the second flow channel 221 can be adjusted respectively to change the jet momentum ratio of the two pulverized coal airflows, so as to change the momentum ratio of the pulverized coal airflows flowing out of the second channel 36 and the first channel 35 respectively. According to Bernoulli's principle, the mutual entrainment effect between the two pulverized coal jets can be changed, and finally the expansion angle of the overall pulverized coal jet formed after the convergence of the two pulverized coal jets can be flexibly adjusted between 0° and a°.

[0039] It can be understood that with the total amount of pulverized coal fixed, when the flow rate of the pulverized coal airflow in the second channel 36 is increased while the flow rate of the pulverized coal airflow in the first channel 35 is decreased, the expansion angle of the overall pulverized coal jet formed after convergence gradually approaches a°. With the total amount of pulverized coal fixed, when the flow rate of the pulverized coal airflow in the second channel 36 is decreased while the flow rate of the pulverized coal airflow in the first channel 35 is increased, the expansion angle of the overall pulverized coal jet formed after convergence gradually approaches 0°.

[0040] When the expansion angle of the overall pulverized coal jet increases, the radial velocity component of the pulverized coal jet flowing around will increase, and at the same time the axial velocity component will decrease, resulting in an accelerated attenuation of the flow velocity of the pulverized coal jet from right to left as a whole. After turning earlier, it flows from left to right, so as to achieve the purpose of reducing the axial length of the high-temperature recirculation zone 111. When the expansion angle of the overall pulverized coal jet decreases, the radial velocity component of the pulverized coal jet flowing around will decrease, and at the same time the axial velocity component will increase, resulting in a slower attenuation of the flow velocity of the pulverized coal jet from right to left as a whole. After delaying the turning, it flows from left to right, so as to achieve the purpose of increasing the axial length of the high-temperature recirculation zone 111, thereby flexibly constructing the distribution of the recirculation zone 111 suitable for the stable combustion of different coal types, and improving the coal type adaptability of the pulverized coal stabilizer and the stability during the operation of the pulverized coal stabilizer.

[0041] In some embodiments, the value range of the included angle a is: 0 ≤ a < 90°.

[0042] Specifically, when no pulverized coal is discharged from the coal outlet 37 in the second flow channel 221 and pulverized coal is discharged from the coal outlet 37 in the first flow channel 211, the pulverized coal jets in the first direction, and at this time the included angle a is 0. When pulverized coal is discharged from the coal outlet 37 in the second flow channel 221 and no pulverized coal is discharged from the coal outlet 37 in the first flow channel 211, the pulverized coal jets along the central axis direction of the outlet of the second channel 36, and at this time 0 < a < 90°.

[0043] In some embodiments, the pulverized coal pipe 2 includes a first pulverized coal pipe 21 and a second pulverized coal pipe 22. One end of the first pulverized coal pipe 21 (such as Figure 1 the right end of the first pulverized coal pipe 21 shown) extends into the chamber 11, and a first flow channel 211 is formed inside the first pulverized coal pipe 21. The second pulverized coal pipe 22 is sleeved outside the first pulverized coal pipe 21. One end of the second pulverized coal pipe 22 (such as Figure 1 the right end of the second pulverized coal pipe 22 shown) extends into the chamber 11. The right end of the first pulverized coal pipe 21 extends out of the right end of the second pulverized coal pipe 22, and a second flow channel 221 is formed between the inner circumferential surface of the second pulverized coal pipe 22 and the outer circumferential surface of the first pulverized coal pipe 21.

[0044] Specifically, both the first pulverized coal pipe 21 and the second pulverized coal pipe 22 are slender straight pipe structures. The inner diameter of the second pulverized coal pipe 22 is larger than the outer diameter of the first pulverized coal pipe 21, and the first pulverized coal pipe 21 and the second pulverized coal pipe 22 are coaxially arranged so that the second flow channel 221 formed between the inner circumferential surface of the second pulverized coal pipe 22 and the outer circumferential surface of the first pulverized coal pipe 21 is an annular flow channel. Through the above arrangement, the structure of the pulverized coal pipe 2 is simple and the manufacturing cost is saved.

[0045] In some embodiments, the central axis of the first flow channel 211 is collinear with the central axis of the second flow channel 221, so that the pulverized coal is annular when flowing out of the second flow channel 221, ensuring the uniformity of the pulverized coal flow in the second flow channel 221 and improving the flow efficiency of the pulverized coal in the second flow channel 221.

[0046] In some embodiments, the pulverized coal stabilizer further includes a branch pipe 4. The branch pipe 4 is arranged at the other end of the second pulverized coal pipe 22 (such as Figure 1 the left end of the second pulverized coal pipe 22 shown). The central axis of the branch pipe 4 is orthogonal to the central axis of the second pulverized coal pipe 22. The other end of the first pulverized coal pipe 21 (such as Figure 1 the left end of the first pulverized coal pipe 21 shown) extends out of the other end of the second pulverized coal pipe 22.

[0047] Specifically, the left end of the second pulverized coal pipe 22 is a closed end, and the left end of the first pulverized coal pipe 21 passes through the left end of the second pulverized coal pipe 22. The branch pipe 4 is a circular short pipe. Valves (not shown) are provided at the upper end of the branch pipe 4 and the left end of the first pulverized coal pipe 21. By respectively adjusting the valve openings provided at the upper end of the first pulverized coal pipe 21 and the branch pipe 4, the flow rates of the pulverized coal air flow flowing into the first pulverized coal pipe 21 and flowing into the second pulverized coal pipe 22 through the branch pipe 4 are adjusted, which is convenient for operation.

[0048] In some embodiments, the coal discharging member 3 includes a protruding portion 31, a first guiding portion 32, an extending portion 33, and a second guiding portion 34. One end of the protruding portion 31 (such as Figure 2The left end of the protruding portion 31 shown) is provided at the right end of the second pulverized coal pipe 22 and is arranged circumferentially around the second pulverized coal pipe 22. The other end of the protruding portion 31 (such as Figure 2 the right end of the protruding portion 31 shown) extends in a direction away from the second pulverized coal pipe 22 along the first direction and is located on the left side of the right end of the first pulverized coal pipe 21.

[0049] Specifically, the protruding portion 31 is an axisymmetric structure with a central channel, and the inner diameter of the central channel of the protruding portion 31 is the same as the inner diameter of the second pulverized coal pipe 22.

[0050] One end of the first guiding portion 32 is provided at the right end of the first pulverized coal pipe 21 and is arranged circumferentially around the first pulverized coal pipe 21. The other end of the first guiding portion 32 extends outward circumferentially along the first pulverized coal pipe 21, and the other end of the first guiding portion 32 is located outside the protruding portion 31. Specifically, the first guiding portion 32 is an axisymmetric structure with a central channel, and the inner diameter of the central channel of the first guiding portion 32 is the same as the inner diameter of the first pulverized coal pipe 21, and the first guiding portion 32 is in a circular ring shape.

[0051] One end of the extending portion 33 (such as Figure 2 the right end of the extending portion 33 shown) is arranged around the other end of the first guiding portion 32. The other end of the extending portion 33 (such as Figure 2 the left end of the extending portion 33 shown) extends toward the protruding portion 31 along the first direction. The extending portion 33 is located outside the protruding portion 31. The inner circumferential surface of the extending portion 33 and the outer circumferential surface of the protruding portion 31 are arranged at intervals, and the second channel 36 is formed between the outer circumferential surface of the protruding portion 31 and the inner circumferential surfaces of the first guiding portion 32 and the extending portion 33.

[0052] Specifically, the second channel 36 can direct the pulverized coal air flow flowing through it to be ejected at a high speed in a conical annular jet. The diameter of the conical pulverized coal jet gradually increases from right to left, and the flow direction of this part of the conical pulverized coal jet injected into the recirculation zone 111 is opposite to the flow direction of the pulverized coal air flow in the second flow channel 221.

[0053] One end of the second guiding portion 34 (such as Figure 2 the left end of the second guiding portion 34 shown) is connected to the outer circumferential surface of the second pulverized coal pipe 22. The coal outlet 37 is formed at one end of the second guiding portion 34 and is opened along the first direction. The second guiding portion 34 has an inner cavity 341. The protruding portion 31, the first guiding portion 32, and the extending portion 33 are located in the inner cavity 341. The first channel 35 is formed between the outer circumferential surfaces of the first guiding portion 32 and the extending portion 33 and the inner circumferential surface of the second guiding portion 34.

[0054] Specifically, the second guiding portion 34 has a cap-shaped axisymmetric structure. The second guiding portion 34 is coaxially arranged with the first guiding portion 32 and covers the right end of the first guiding portion 32, so that the first channel 35 is formed between the inner peripheral surface of the second guiding portion 34 and the outer peripheral surfaces of the first guiding portion 32 and the extending portion 33. The first channel 35 can guide the pulverized coal air flow flowing through it into an equal-diameter annular jet and eject it at a high speed, and the flowing direction of this part of the equal-diameter annular pulverized coal jet flowing into the recirculation zone 111 is opposite to its flowing direction in the first pulverized coal pipe 21.

[0055] Specifically, there are a plurality of coal outlets 37, and the plurality of coal outlets 37 are arranged at intervals around the circumference of the left end face of the second guiding portion 34.

[0056] In some embodiments, the outer peripheral surface of the protruding portion 31 is an inclined surface extending in the first direction and gradually moving away from the second pulverized coal pipe 22 from the right end to the left end of the protruding portion 31.

[0057] Specifically, the outer peripheral contour of the protruding portion 31 is frustum-shaped, the cross-sectional area of the outer peripheral contour of the protruding portion 31 gradually increases from the right end to the left end of the protruding portion 31, and the diameter of the outer peripheral contour at the left end of the protruding portion 31 is larger than the outer diameter of the second pulverized coal pipe 22.

[0058] In some embodiments, the inner peripheral surface of the extending portion 33 is an inclined surface and is adapted to the outer peripheral surface of the protruding portion 31, so that an included angle a is formed between the central axis of the end of the second channel 36 adjacent to the coal outlet 37 and the central axis of the coal outlet 37, and the central axis of the end of the first channel 35 adjacent to the coal outlet 37 is parallel to the central axis of the coal outlet 37.

[0059] Specifically, the outer peripheral contour of the extending portion 33 is cylindrical, the inner peripheral contour of the extending portion 33 is frustum-shaped, and the cross-section of the inner peripheral contour of the extending portion 33 gradually increases from the right end to the left end of the extending portion 33, so that the inclination degree of the inner peripheral surface of the extending portion 33 is adapted to the outer peripheral surface of the protruding portion 31, so that an included angle can be formed between the flowing direction of the pulverized coal air flow ejected through the second channel 36 and the flowing direction of the pulverized coal air flow ejected from the first channel 35.

[0060] In some embodiments, the central axis of the protruding portion 31, the central axis of the first guiding portion 32, and the central axis of the second guiding portion 34 are collinear, ensuring that the annular pulverized coal jet ejected from the first channel 35 at a high speed and the conical annular pulverized coal jet ejected from the second channel 36 at a high speed are evenly distributed.

[0061] The operation method of the pulverized coal stabilizer according to the embodiment of the present invention includes:

[0062] Pulverized coal is introduced into the first pulverized coal pipe 21, and the pulverized coal in the first pulverized coal pipe 21 flows into the first channel 35 and flows out from the coal outlet 37. Pulverized coal is introduced into the second pulverized coal pipe 22, and the pulverized coal in the second pulverized coal pipe 22 flows into the second channel 36 and flows out from the coal outlet 37. By adjusting the amount of pulverized coal introduced into the first pulverized coal pipe 21 and the amount of pulverized coal introduced into the second pulverized coal pipe 22, the size of the included angle a can be adjusted.

[0063] Specifically, with the total amount of pulverized coal fixed, when the flow rate of the pulverized coal air flow in the second channel 36 is increased while the flow rate of the pulverized coal air flow in the first channel 35 is decreased, the expansion angle of the overall pulverized coal jet formed after convergence gradually approaches a°. With the total amount of pulverized coal fixed, when the flow rate of the pulverized coal air flow in the second channel 36 is decreased while the flow rate of the pulverized coal air flow in the first channel 35 is increased, the expansion angle of the overall pulverized coal jet formed after convergence gradually approaches 0°.

[0064] In the operation method of the pulverized coal stabilizer according to the embodiment of the present invention, when the included angle a increases, the radial velocity component of the pulverized coal jet flowing radially around at the coal outlet 37 increases, and the axial velocity component decreases, causing the flow rate attenuation of the pulverized coal jet as a whole from one end of the pulverized coal pipe 2 to the other end of the pulverized coal pipe 2 to accelerate. After early turning, it flows from the other end of the pulverized coal pipe 2 to one end of the pulverized coal pipe 2, thereby achieving the purpose of reducing the axial length of the recirculation zone 111 in the chamber 11. When the included angle a decreases, the radial velocity component of the pulverized coal jet flowing radially around at the coal outlet 37 decreases, and at the same time the axial velocity component increases, causing the flow rate attenuation of the pulverized coal jet as a whole from one end of the pulverized coal pipe 2 to the other end of the pulverized coal pipe 2 to slow down. After delaying turning, it flows from the other end of the pulverized coal pipe 2 to one end of the pulverized coal pipe 2, thereby achieving the purpose of increasing the axial length of the recirculation zone 111 in the chamber 11, thereby flexibly constructing the distribution of the recirculation zone 111 suitable for stable combustion of different coal types and improving the coal type adaptability of the pulverized coal stabilizer.

[0065] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "right", "left", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 construed as a limitation of the present invention.

[0066] In addition, 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 quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0067] In the present invention, unless otherwise clearly defined and limited, terms such as "mounted", "connected", "connected to", "fixed" and the like shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection or communicable with each other; it may be directly connected, or indirectly connected through an intermediate medium, and may be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, 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 defined and limited, the first feature being "on" or "under" the second feature may be 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, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "below" and "beneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely means that the horizontal height of the first feature is less than that of the second feature.

[0069] In the present invention, terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions 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 a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0070] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A pulverized coal stable combustion burner, characterized in that, Comprising: A body (1), one end of the body (1) having a chamber (11), and a reflux zone (111) being provided in the chamber (11); A pulverized coal pipe (2), one end of the pulverized coal pipe (2) extending into the chamber (11), the pulverized coal pipe (2) having a first flow channel (211) and a second flow channel (221), the second flow channel (221) being sleeved outside the first flow channel (211), both the first flow channel (211) and the second flow channel (221) being in communication with the chamber (11), and pulverized coal can be introduced into the chamber (11) through the first flow channel (211) and the second flow channel (221); A coal discharging member (3), the coal discharging member (3) being provided at one end of the pulverized coal pipe (2), the coal discharging member (3) having a first channel (35), a second channel (36) and a coal discharging port (37), one end of the first channel (35) being in communication with the first flow channel (211), one end of the second channel (36) being in communication with the second flow channel (221), the other ends of both the first channel (35) and the second channel (36) being in communication with the coal discharging port (37), the coal discharging port (37) being located in the reflux zone (111) and the coal discharging port (37) being opened towards the other end of the pulverized coal pipe (2), and the pulverized coal in the first flow channel (211) and the pulverized coal in the second flow channel (221) flow into the reflux zone (111) through the coal discharging port (37), There is an included angle a between the flow direction of the pulverized coal flowing out through the first channel (35) and the flow direction of the pulverized coal flowing out through the second channel (36). By adjusting the amount of pulverized coal in the first flow channel (211) and the amount of pulverized coal in the second flow channel (221), the flow direction of the pulverized coal flowing out through the first channel (35) and the flow direction of the pulverized coal flowing out through the second channel (36) are changed, so that the magnitude of the included angle a is adjustable.

2. The pulverized coal stable combustion burner according to claim 1, wherein, The value range of the included angle a is: 0 ≤ a < 90°.

3. The pulverized coal stable combustion burner according to claim 1, characterized in that, The pulverized coal pipe (2) includes: A first pulverized coal pipe (21), one end of the first pulverized coal pipe (21) extending into the chamber (11), and the first flow channel (211) being formed inside the first pulverized coal pipe (21); A second pulverized coal pipe (22), the second pulverized coal pipe (22) being sleeved outside the first pulverized coal pipe (21), one end of the second pulverized coal pipe (22) extending into the chamber (11), one end of the first pulverized coal pipe (21) protruding from one end of the second pulverized coal pipe (22), and the second flow channel (221) being formed between the inner peripheral surface of the second pulverized coal pipe (22) and the outer peripheral surface of the first pulverized coal pipe (21).

4. The pulverized coal stable combustion burner according to claim 3, characterized in that, The central axis of the first flow channel (211) is collinear with the central axis of the second flow channel (221).

5. The pulverized coal stable combustion burner according to claim 3, characterized in that, The coal discharging member (3) includes: The protruding portion (31), one end of the protruding portion (31) is provided at one end of the second pulverized coal pipe (22) and is arranged circumferentially around the second pulverized coal pipe (22), and the other end of the protruding portion (31) extends in a first direction away from the second pulverized coal pipe (22); The first guiding portion (32) and the extending portion (33), one end of the first guiding portion (32) is provided at one end of the first pulverized coal pipe (21) and is arranged circumferentially around the first pulverized coal pipe (21), the other end of the first guiding portion (32) extends outward circumferentially along the first pulverized coal pipe (21), the other end of the first guiding portion (32) is located outside the protruding portion (31), one end of the extending portion (33) is arranged around the other end of the first guiding portion (32), the other end of the extending portion (33) extends in the first direction toward the protruding portion (31), the extending portion (33) is located outside the protruding portion (31), and the second channel (36) is formed between the outer peripheral surface of the protruding portion (31) and the inner peripheral surfaces of the first guiding portion (32) and the extending portion (33); The second guiding portion (34), one end of the second guiding portion (34) is connected to the outer peripheral surface of the second pulverized coal pipe (22), the coal outlet (37) is formed at one end of the second guiding portion (34) and is opened in the first direction, the second guiding portion (34) has a cavity (341), the protruding portion (31), the first guiding portion (32) and the extending portion (33) are located in the cavity (341), and the first channel (35) is formed between the outer peripheral surfaces of the first guiding portion (32) and the extending portion (33) and the inner peripheral surface of the second guiding portion (34).

6. The pulverized coal stable combustion burner according to claim 5, characterized in that, The outer peripheral surface of the protruding portion (31) is an inclined surface that extends in the first direction and gradually moves away from the second pulverized coal pipe (22) from the other end of the protruding portion (31) to one end of the protruding portion (31).

7. The pulverized coal stable combustion burner according to claim 6, characterized in that, The inner peripheral surface of the extending portion (33) is an inclined surface and is adapted to the outer peripheral surface of the protruding portion (31), so that an included angle a is formed between the central axis of the end of the second channel (36) adjacent to the coal outlet (37) and the central axis of the coal outlet (37), and the central axis of the end of the first channel (35) adjacent to the coal outlet (37) is parallel to the central axis of the coal outlet (37).

8. The pulverized coal stable combustion burner according to claim 5, characterized in that, The central axes of the protruding portion (31), the first guiding portion (32) and the second guiding portion (34) are collinear.

9. The pulverized coal stable combustion burner according to claim 3, characterized in that, It further includes a branch pipe (4), the branch pipe (4) is provided at the other end of the second pulverized coal pipe (22), the central axis of the branch pipe (4) is orthogonal to the central axis of the second pulverized coal pipe (22), and the other end of the first pulverized coal pipe (21) extends out of the other end of the second pulverized coal pipe (22).

10. A method for operating a pulverized coal stable combustion burner according to any one of claims 1-9, characterized in that, Comprising: Pulverized coal is introduced into the first pulverized coal pipe (21), and the pulverized coal in the first pulverized coal pipe (21) flows into the first channel (35) and flows out from the coal outlet (37); Inject pulverized coal into the second pulverized coal pipe (22), and the pulverized coal in the second pulverized coal pipe (22) flows into the second channel (36) and flows out from the coal outlet (37). Adjust the amount of pulverized coal injected into the first pulverized coal pipe (21) and the amount of pulverized coal injected into the second pulverized coal pipe (22), and the size of the included angle a can be adjusted.

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