Burners that adapt fuel supply based on changes in combustion air flow

Abstract

The present invention discloses a burner that adapts to fuel supply based on changes in combustion-supporting air flow rate, comprising a flame nozzle, a combustion-supporting air pipe and a fuel supply pipe, wherein one end of the flame nozzle is a flame injection port, and the flame nozzle is a mixed combustion chamber, and the lead-out end of the combustion-supporting air pipe is connected to the tail end of the mixed combustion chamber; the fuel lead-out port of the fuel supply pipe extends into the mixed combustion chamber; a coal powder dispersion unit is provided in the ventilation channel in the combustion-supporting air pipe, and the coal powder dispersion unit evenly disperses the coal powder in the ventilation channel, and can stabilize the ratio of the flow rate of the combustion-supporting air to the amount of coal powder introduced within a reasonable range.

Description

Technical Field

[0001] The invention belongs to the field of burners. Background Art

[0002] Flame-throwing burners that use liquid or gaseous energy sources such as natural gas and ethanol as their primary fuel are widely used in the industrial sector. While pulverized coal is inexpensive, due to its solid nature, it cannot be quantitatively fed through fluid pipelines, making it difficult to use as the sole fuel in flame-throwing burners. In burners, pulverized coal is typically fed at a uniform rate into a pipeline used to deliver combustion-supporting air through a feeding mechanism. This allows the pulverized coal to be carried into the combustion chamber along with the combustion air and combusted in combination with the gas or liquid fuel in the combustion chamber, thereby reducing the consumption of relatively expensive fuels such as natural gas and ethanol.

[0003] In this existing mixed burner structure, there is no mutual constraint between the flow rate of combustion air and the amount of coal powder introduced. If the flow rate of combustion air increases, it will not lead to an increase in the amount of coal powder introduced, which will cause an imbalance in the ratio of the flow rate of combustion air and the amount of coal powder introduced. Summary of the Invention

[0004] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a burner that adapts to the supply of fuel based on changes in the combustion air flow rate, which can stabilize the ratio of the combustion air flow rate to the coal powder introduction amount within a reasonable range.

[0005] Technical solution: To achieve the above-mentioned purpose, the burner of the present invention includes a flame nozzle, a combustion-supporting air pipe and a fuel supply pipe. One end of the flame nozzle is a flame injection port, and the flame nozzle is a mixed combustion chamber. The lead-out end of the combustion-supporting air pipe is connected to the tail of the mixed combustion chamber; the fuel lead-out port of the fuel supply pipe extends into the mixed combustion chamber; a coal powder dispersion unit is provided in the ventilation channel in the combustion-supporting air pipe, and the coal powder dispersion unit evenly disperses the coal powder in the ventilation channel.

[0006] Furthermore, a blower is provided at the air inlet end of the combustion air pipe.

[0007] Furthermore, the power of the coal powder discharging mechanism on the coal powder dispersion unit is driven by the upward airflow of the ventilation channel.

[0008] Furthermore, the combustion air flow rate in the ventilation channel is positively correlated with the coal powder discharge rate of the coal powder dispersion unit.

[0009] Furthermore, the pulverized coal dispersion unit includes a fixed pulverized coal temporary storage box, which contains a pulverized coal temporary storage bin; and also includes a pulverized coal feed pipe, the discharge end of which is connected to the pulverized coal temporary storage bin;

[0010] A batching ring wall is integrated at the lower end of the temporary storage box for pulverized coal, and a bearing sleeve is fixedly connected to the lower end of the batching ring wall coaxially. A disc-shaped gyroscope-shaped impeller is coaxially arranged below the bearing sleeve, and a wind pressure cylinder is coaxially integrated with the axis of the impeller. A linkage shaft is fixedly connected coaxially to the upper end of the wind pressure cylinder, and the linkage shaft rotates with the bearing sleeve through a bearing. A center wheel is fixedly connected coaxially to the upper end of the linkage shaft, and a number of axial flow wind blades are distributed in a circular array on the lower surface of the impeller.

[0011] Furthermore, an annular guide cover is coaxially arranged on the outer periphery of the batching ring wall, and the upper end contour of the annular guide cover is integrally connected to the outer wall of the pulverized coal temporary storage box, forming a pulverized coal dispersion annular cavity between the annular guide cover and the impeller;

[0012] The coal powder transfer bin is enclosed within the range of the batching ring wall. The side walls of the batching ring wall are hollowed out in a circular array with a number of side openings. Each side opening is movably filled with a columnar follower wheel with a vertical axis. The bearing hole at the axis of the columnar follower wheel is rotatably mounted on the fixed shaft through a bearing. The center wheel and each columnar follower wheel are in rolling cooperation, and the rotation of the center wheel drives the rotation of each columnar follower wheel.

[0013] One side of each columnar follower wheel protrudes into the coal powder transfer bin, and the other side of each columnar follower wheel protrudes into the coal powder dispersion annular cavity; a circle of sunken annular groove is provided on the contour edge of the upper surface of each columnar follower wheel, and a number of dividing strips extending in the radial direction are distributed in a circular array in the sunken annular groove, and a fan-shaped unit groove is formed between any two adjacent dividing strips; an annular coal powder outlet is formed between the lower end contour of the annular guide cover and the outer contour of the impeller.

[0014] Furthermore, the annular coal powder outlet and the ventilation channel form a narrow annular ventilation channel around the coal powder dispersion unit, and the annular ventilation channel is connected to the coal powder dispersion annular cavity through the annular coal powder outlet; the wind pressure cylinder is a wind pressure channel with an open lower end, and the upper end of the wind pressure channel is connected to the longitudinal area of ​​the coal powder dispersion annular cavity through a number of connecting holes on the side wall; the upper surface of the impeller is provided with a number of swirl centrifugal blades distributed in a circular array, and the rotation of the impeller causes the number of swirl centrifugal blades to drive the gas in the coal powder dispersion annular cavity to form a swirl.

[0015] Furthermore, the bearing hole at the axis center of the columnar follower wheel is rotatably mounted on the fixed shaft through the bearing; the upper and lower ends of each fixed shaft are fixedly connected to the upper and lower walls of the side opening respectively.

[0016] Beneficial effects: From the structural principle, it can be seen that the rotational speed of the cylindrical follower wheel of the present invention is basically proportional to the amount of coal powder thrown into the coal powder dispersion annular cavity, and the rotational speed of the cylindrical follower wheel is proportional to the rotational speed of the impeller, and the rotational speed of the impeller is positively correlated with the air flow rate in the ventilation channel. It can be seen that in this method, the flow rate of the combustion air in the ventilation channel is highly positively correlated with the mass of the entrained coal powder, which ensures the stability of the ratio of combustion air to coal powder in the ventilation channel at different flow rates, thereby stabilizing the combustion efficiency in the mixed combustion chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Attachment Figure 1 Schematic diagram of the overall structure;

[0018] Attachment Figure 2 is a cross-sectional view of the burner;

[0019] Attachment Figure 3 It is a cross-sectional view of the structure of the pulverized coal dispersion unit;

[0020] Attachment Figure 4 This is a schematic diagram of the three-dimensional structure of the coal powder dispersion unit;

[0021] Attachment Figure 5 It is a three-dimensional cross-sectional view of the coal powder dispersion unit;

[0022] Attachment Figure 6 This is a disassembly diagram of the pulverized coal dispersion unit;

[0023] Attachment Figure 7 For attachment Figure 6 sectional view of

[0024] Attachment Figure 8 This is a schematic diagram of the structure of the temporary storage box for pulverized coal;

[0025] Attachment Figure 9 Schematic diagram of the structure of a single cylindrical follower wheel. DETAILED DESCRIPTION

[0026] The present invention will be further described below with reference to the accompanying drawings.

[0027] As attached Figures 1 to 9 The burner shown is adapted to supply fuel based on the change of combustion air flow rate, such as Figure 1 and 2, including a horizontal flame nozzle 18, a vertical combustion-supporting air pipe 1 and a fuel supply pipe 21. The fuel supplied by the fuel supply pipe 21 can be natural gas. One end of the flame nozzle 18 is a flame injection port 23. The flame nozzle 18 has a conical mixed combustion chamber 22. The air outlet end at the upper end of the combustion-supporting air pipe 1 is connected to the tail of the mixed combustion chamber 22 through a bend pipe; the fuel outlet 20 of the fuel supply pipe 21 extends into the mixed combustion chamber 22, and an ignition device is provided in the mixed combustion chamber 22; a centrifugal blower is provided at the air inlet end of the combustion-supporting air pipe 1 to form an ascending airflow in the fuel supply pipe 21; a coal powder dispersion unit 25 is provided in the ventilation channel 24 in the combustion-supporting air pipe 1, and the coal powder dispersion unit 25 evenly disperses the coal powder in the ventilation channel 24. The coal powder dispersed in the ventilation channel 24 flows into the mixed combustion chamber 22 together under the wind flow of the ventilation channel 24, thereby achieving the purpose of reducing the consumption of relatively expensive fuels such as natural gas and ethanol.

[0028] The power of the coal powder discharging mechanism on the coal powder dispersion unit 25 is driven by the upward airflow of the ventilation channel 24, so that the combustion air flow in the ventilation channel 24 is positively correlated with the coal powder discharging rate of the coal powder dispersion unit 25, so that the flow rate of the combustion air and the amount of coal powder introduced are mutually constrained, and the ratio of the combustion air and coal powder in the ventilation channel is stabilized at different flow rates, thereby stabilizing the combustion efficiency in the mixed combustion chamber.

[0029] The specific structure of the pulverized coal dispersion unit 25 is as follows:

[0030] like Figure 3 、 4 , 5, 6, 7, and 8 show that the coal powder dispersion unit 25 includes a funnel-shaped coal powder temporary storage box 3 that is coaxial with the combustion-supporting air pipe 1, and the coal powder temporary storage box 3 contains a coal powder temporary storage bin 7; the coal powder temporary storage box 3 is fixedly connected to the combustion-supporting air pipe 1 through a support arm 19; and also includes a coal powder feed pipe 5, the discharge end of the coal powder feed pipe 5 is connected to the coal powder temporary storage bin 7.

[0031] The lower end of the temporary storage box 3 of coal powder is integrated with a material ring wall 32, and the lower end of the material ring wall 32 is coaxially fixedly connected to a bearing sleeve 33, and a disc-shaped gyroscope-shaped impeller 16 is coaxially provided below the bearing sleeve 33. The interior of the impeller 16 of this embodiment is hollow 13 to reduce the overall weight. The axis of the impeller 16 is coaxially integrated with a wind pressure cylinder 41, and the upper end of the wind pressure cylinder 41 is coaxially fixedly connected to a linkage shaft 26. The linkage shaft 26 rotates with the bearing sleeve 33 through a bearing, and the upper end of the linkage shaft 26 is coaxially fixedly connected to a center wheel 6 with a pointed cone at the upper end. A plurality of axial flow pneumatic blades 12 are distributed in a circular array on the lower surface of the impeller 16; the continuous upward flow in the ventilation channel 24 will drive the impeller 16 to rotate at high speed through a plurality of axial flow pneumatic blades 12.

[0032] An annular guide hood 8 is coaxially arranged on the outer periphery of the batching ring wall 32, and the upper end contour of the annular guide hood 8 is integrally connected to the outer wall of the coal powder temporary storage box 3, and a coal powder dispersion annular cavity 17 is formed between the annular guide hood 8 and the impeller 16; the coal powder transfer bin 35 is enclosed within the range of the batching ring wall 32, and a plurality of side openings 31 are hollowed out in a circular array on the side wall of the batching ring wall 32, and each side opening 31 is movably filled with a columnar follower wheel 2 with a vertical axis, and the bearing hole 27 at the axis center of the columnar follower wheel 2 is rotatably mounted on the fixed shaft 30 through a bearing; the center wheel 6 is in rolling cooperation with each columnar follower wheel 2, and the rotation of the center wheel 6 drives each columnar follower wheel 2 to rotate; the specific structure of the columnar follower wheel 2 is as follows Figure 9 shown.

[0033] like Figure 8 , the upper and lower ends of each fixed shaft 30 are fixedly connected to the upper and lower walls of the side opening 31; Figure 5 and 7 , one side of each columnar follower wheel 2 protrudes into the coal powder transfer bin 35, and the other side of each columnar follower wheel 2 protrudes into the coal powder dispersion annular cavity 17; a circle of sunken annular groove 28 is provided on the contour edge of the upper surface of each columnar follower wheel 2, and a plurality of dividing strips 29 extending in the radial direction are distributed in a circumferential array in the sunken annular groove 28, and a fan-shaped unit groove 53 is formed between any two adjacent dividing strips 29; when the fan-shaped unit groove 53 is in the coal powder transfer bin 35, the fan-shaped unit groove 53 will be naturally filled with the coal powder in the coal powder transfer bin 35. During the continuous rotation of the columnar follower wheel 2, the upper side of the columnar follower wheel 2 Each fan-shaped unit groove 53 will periodically move from the coal powder transfer bin 35 to the coal powder dispersion annular cavity 17. Each fan-shaped unit groove 53 will temporarily store a certain amount of coal powder every time it arrives at the coal powder transfer bin 35. Each fan-shaped unit groove 53 will temporarily store a certain amount of coal powder every time it arrives at the coal powder dispersion annular cavity 17. The coal powder temporarily stored in the fan-shaped unit groove 53 will be thrown into the coal powder dispersion annular cavity 17 under the centrifugal force of the rotation of the columnar follower wheel 2 itself. As the columnar follower wheels 2 continue to rotate, each fan-shaped unit groove 53 will continuously throw the coal powder from the coal powder transfer bin 35 into the coal powder dispersion annular cavity 17.

[0034] An annular pulverized coal outlet 10 is formed between the lower end contour of the annular guide cover 8 and the outer contour of the impeller 16. The annular pulverized coal outlet 10 and the ventilation channel 24 form a narrow annular ventilation channel 24.1 around the coal powder dispersion unit 25, resulting in a higher flow rate of the rising balloon at the annular ventilation channel 24.1 than in other areas of the ventilation channel 24. According to the Bernoulli equation of fluid mechanics, the greater the flow rate, the lower the pressure, thereby forming a low-pressure environment at the narrow ventilation channel 24.1. The annular pulverized coal outlet 1 is connected to the coal powder dispersion annular cavity 17 through the annular pulverized coal outlet 1. 0 connection; the wind pressure cylinder 41 contains a wind pressure channel 14 with an open lower end, and the upper end of the wind pressure channel 14 is connected to the axial area of ​​the coal powder dispersion annular cavity 17 through a plurality of connecting holes 15 on the side wall. The upward wind pressure in the ventilation channel 24 is transmitted to the coal powder dispersion annular cavity 17 through the wind pressure channel 14 and the plurality of connecting holes 15, so that the mixed gas of air and coal powder in the coal powder dispersion annular cavity 17 is pressurized; the upper surface of the impeller 16 has a plurality of swirl centrifugal blades 9 distributed in a circumferential array. The rotation of the impeller 16 causes the plurality of swirl centrifugal blades 9 to drive the gas in the coal powder dispersion annular cavity 17 to form a swirl.

[0035] An appropriate amount of pulverized coal is introduced into the temporary pulverized coal storage bin 7 in real time through the pulverized coal feed pipe 5. The pulverized coal entering the temporary pulverized coal storage bin 7 slides down to the pulverized coal transfer bin 35 under the action of gravity, so that the pulverized coal transfer bin 35 is always filled with a certain amount of pulverized coal. The blower is started, so that the combustion air continuously flows upward in the ventilation channel 24 under the action of the wind pressure of the blower, and finally merges with the liquid or gaseous fuel discharged from the fuel outlet 20 of the fuel supply pipe 21 in the mixed combustion chamber 22, and is ignited by the igniter. The flame in the mixed combustion chamber 22 is finally ejected from the flame injection port 23 into the furnace.

[0036] On the basis of the above process, the following process will also occur:

[0037] The continuous upward flow in the ventilation channel 24 will drive the impeller 16 to rotate at high speed through a number of axial flow wind blades 12, and the center wheel 6 will rotate synchronously with the impeller 16. The rotation of the center wheel 6 will drive each column follower wheel 2 to rotate continuously. Since one side of the column follower wheel 2 protrudes from the coal powder transfer bin 35 and the other side protrudes from the coal powder dispersion annular cavity 17, during the continuous rotation of the column follower wheel 2, each fan-shaped unit groove 53 on the upper side of the column follower wheel 2 will periodically move from the coal powder transfer bin 35 to the coal powder dispersion annular cavity 17. Each fan-shaped unit groove 53 will temporarily store a certain amount of coal powder every time it reaches the coal powder transfer bin 35. Each time the element groove 53 reaches the coal powder dispersion annular cavity 17, the coal powder temporarily stored in the sector-shaped unit groove 53 will be thrown into the coal powder dispersion annular cavity 17 under the centrifugal force of the rotation of the columnar follower wheel 2 itself. As each columnar follower wheel 2 continues to rotate, each sector-shaped unit groove 53 will continuously throw the coal powder from the coal powder transfer bin 35 into the coal powder dispersion annular cavity 17; the rotation of the impeller 16 causes the plurality of swirl centrifugal blades 9 to drive the gas in the coal powder dispersion annular cavity 17 to form a swirl flow, and the coal powder thrown from each sector-shaped unit groove 53 into the coal powder dispersion annular cavity 17 is evenly dispersed in the coal powder dispersion annular cavity 17 under the action of the swirl flow in the coal powder dispersion annular cavity 17;

[0038] At the same time, the upward wind pressure in the ventilation channel 24 is transmitted to the coal powder dispersion annular cavity 17 through the wind pressure channel 14 and a plurality of connecting holes 15, so that the mixed gas of air and coal powder in the coal powder dispersion annular cavity 17 is pressurized. Since the coal powder dispersion unit 25 in the center occupies the central part of the channel in the ventilation channel 24, the ventilation channel 24 forms a narrow annular ventilation channel 24.1 around the coal powder dispersion unit 25, resulting in a higher flow rate of the rising balloon at the annular ventilation channel 24.1 than other areas of the ventilation channel 24. According to the Bernoulli equation of fluid mechanics, the greater the flow rate, the higher the pressure. The smaller the pressure, the lower the pressure, thus forming a low-pressure environment in the narrow ventilation passage 24.1. The pulverized coal and air mixture uniformly dispersed in the pulverized coal dispersion annular cavity 17 and in a high-pressure environment is continuously sucked out through the annular pulverized coal outlet 10 into the narrow ventilation passage 24.1 in a low-pressure environment, so that the ventilation passage 24 continuously and evenly carries the pulverized coal upward. Ultimately, the combustion-supporting air uniformly carrying the pulverized coal and the liquid or gaseous fuel discharged from the fuel outlet 20 of the fuel supply pipe 21 merge in the mixing combustion chamber 22 to form a mixed fuel, which is finally ejected from the flame injection port 23 into the furnace in the form of a flame.

[0039] In the above process, the rotation speed of the columnar follower wheel 2 is basically proportional to the amount of coal powder thrown into the coal powder dispersion annular cavity 17, and the rotation speed of the columnar follower wheel 2 is proportional to the rotation speed of the impeller 16, and the rotation speed of the impeller 16 is positively correlated with the air flow rate in the ventilation channel 24. Combining the above directions, it can be seen that in this method, the flow rate of the combustion air in the ventilation channel 24 is highly positively correlated with the mass of the entrained coal powder, which ensures the stability of the ratio of combustion air to coal powder in the ventilation channel 24 at different flow rates, thereby stabilizing the combustion efficiency in the mixed combustion chamber 22.

[0040] The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A burner that adapts fuel supply based on changes in combustion air flow, characterized in that: It comprises a flame nozzle (18), a combustion-supporting air pipe (1) and a fuel supply pipe (21), wherein one end of the flame nozzle (18) is a flame injection port (23), the flame nozzle (18) contains a mixing combustion chamber (22), the lead-out end of the combustion-supporting air pipe (1) is connected to the rear end of the mixing combustion chamber (22); the fuel lead-out port (20) of the fuel supply pipe (21) extends into the mixing combustion chamber (22); a pulverized coal dispersion unit (25) is provided in the ventilation channel (24) in the combustion-supporting air pipe (1), and the pulverized coal dispersion unit (25) evenly disperses the pulverized coal in the ventilation channel (24); The combustion air flow rate in the ventilation channel (24) is positively correlated with the coal powder discharge rate of the coal powder dispersion unit (25); The pulverized coal dispersion unit (25) includes a fixed pulverized coal temporary storage box (3), and the pulverized coal temporary storage box (3) contains a pulverized coal temporary storage bin (7); The lower end of the temporary coal powder storage box (3) is integrally provided with a batching ring wall (32), the lower end of the batching ring wall (32) is coaxially fixedly connected to a bearing sleeve (33), a disc-shaped gyroscope-shaped impeller (16) is coaxially provided below the bearing sleeve (33), the axis of the impeller (16) is coaxially integrated with a wind pressure cylinder (41), the upper end of the wind pressure cylinder (41) is coaxially fixedly connected to a linkage shaft (26), the linkage shaft (26) is rotatably matched with the bearing sleeve (33) through a bearing, the upper end of the linkage shaft (26) is coaxially fixedly connected to a center wheel (6), and a plurality of axial flow wind blades (12) are distributed in a circular array on the lower surface of the impeller (16).

2. The burner capable of adaptively supplying fuel based on changes in combustion air flow rate according to claim 1, characterized in that: The air inlet end of the combustion-supporting air pipe (1) is provided with a blower; the power of the coal powder discharging mechanism on the coal powder dispersion unit (25) is driven by the upward airflow in the ventilation channel (24).

3. The burner capable of adaptively supplying fuel based on changes in combustion air flow rate according to claim 1, characterized in that: An annular flow guide hood (8) is coaxially arranged on the outer periphery of the batching ring wall (32), and the upper end contour of the annular flow guide hood (8) is integrally connected to the outer wall of the coal powder temporary storage box (3), and a coal powder dispersion annular cavity (17) is formed between the annular flow guide hood (8) and the impeller (16); the coal powder transfer bin (35) is enclosed within the batching ring wall (32), and the side wall of the batching ring wall (32) is hollowed out to have a plurality of side openings (31), and each side opening (31) is movably filled with a columnar follower wheel (2); the center wheel (6) and each columnar follower wheel (2) are in rolling cooperation, and the rotation of the center wheel (6) drives each columnar follower wheel (2) to rotate; One side of each columnar follower wheel (2) protrudes into the coal powder transfer bin (35), and the other side protrudes into the coal powder dispersion annular cavity (17); a circle of sunken annular grooves (28) is provided on the contour edge of the upper surface of each columnar follower wheel (2), and a plurality of dividing strips (29) extending in the radial direction are distributed in a circumferential array in the sunken annular groove (28), and a fan-shaped unit groove (53) is formed between any two adjacent dividing strips (29); an annular coal powder outlet (10) is formed between the lower end contour of the annular guide cover (8) and the outer contour of the impeller (16).

4. The burner capable of adaptively supplying fuel based on changes in combustion air flow rate according to claim 3, characterized in that: The ventilation channel (24) forms a narrow annular ventilation channel (24.1) around the coal powder dispersion unit (25), and the annular ventilation channel (24.1) is connected to the coal powder dispersion annular cavity (17) through the annular coal powder outlet (10); the wind pressure cylinder (41) contains a wind pressure channel (14) with an open lower end, and the upper end of the wind pressure channel (14) is connected to the axial center area of ​​the coal powder dispersion annular cavity (17) through a plurality of connecting holes (15) on the side wall; the upper surface of the impeller (16) is provided with a plurality of swirl centrifugal blades (9) distributed in a circumferential array, and the rotation of the impeller (16) causes the plurality of swirl centrifugal blades (9) to drive the gas in the coal powder dispersion annular cavity (17) to form a swirl.

5. The burner capable of adaptively supplying fuel based on changes in combustion air flow rate according to claim 4, characterized in that: The bearing hole (27) at the axis of the columnar follower wheel (2) is rotatably mounted on the fixed shaft (30) via a bearing; the upper and lower ends of each fixed shaft (30) are respectively fixedly connected to the upper and lower walls of the side opening (31).

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