Plasma burner

Abstract

The invention belongs to the field of plasma ignition combustors, and particularly discloses a plasma combustor which comprises a furnace body, a second combustion cavity is formed in the top of the furnace body, a first combustion cavity communicating with the second combustion cavity is formed in the furnace body, and a plasma igniter is arranged at the lower end of the surface of the furnace body. One end of the plasma igniter extends into the first combustion cavity, a recycling pipe is arranged in the second combustion cavity, the lower end of the recycling pipe penetrates out of the furnace body, and a first air inlet assembly is arranged on the surface of the furnace body. By arranging the second gas inlet assembly, gas film protection can be formed in the communication section of the first combustion chamber and the second combustion chamber, and a gas film can cool the wall surface and physically block contact between molten ash and the furnace wall, so that adhesion and accumulation of the ash in the area are prevented, the slag bonding risk is fundamentally reduced, and the service life of the furnace is prolonged. And long-term continuous and stable operation of the boiler is ensured.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of plasma ignition burners, and specifically discloses a plasma burner. BACKGROUND

[0002] Coal combustion technology is widely used in the industrial fields of electric power, metallurgy, chemical industry and the like, and its combustion efficiency and operation stability are directly related to energy utilization rate and production cost. As an advanced ignition and stable combustion technology, the plasma igniter has been widely used in coal-fired boilers, and particularly exhibits significant advantages when igniting low-volatile coal; In the combustion process of coal, the ash contained in the coal is melted into a liquid state at high temperature. In the traditional straight-flow or weakly swirling burner, the molten ash is easily impacted by airflow and adheres to the heated surface such as the water-cooled wall of the furnace, and with the passage of time, the adhering matter continuously accumulates to form hard slag. The slag not only reduces the heat conduction efficiency in the furnace and affects the output of the boiler, but also even needs to be stopped for slag removal, which greatly increases the maintenance cost and operation risk. Therefore, the plasma burner is proposed by the person skilled in the art to solve the above problems. SUMMARY

[0003] Therefore, the technical problem to be solved by the present application is to provide a plasma burner to solve the problem of ash adhesion and difficulty in cleaning in the prior art.

[0004] To achieve the above purposes, the present application provides a plasma burner, which comprises a furnace body, a second combustion chamber is formed at the top of the furnace body, a first combustion chamber is formed in the interior of the furnace body and communicates with the second combustion chamber, a plasma igniter is arranged at the lower end of the surface of the furnace body, one end of the plasma igniter extends into the interior of the first combustion chamber, a recovery pipe is arranged in the interior of the second combustion chamber, the lower end of the recovery pipe penetrates out of the furnace body, a first air inlet assembly is arranged on the surface of the furnace body, a second air inlet assembly is arranged above the first air inlet assembly, and the upper end of the recovery pipe is arranged in a funnel shape. The second air inlet assembly comprises a fixed block fixedly connected to the surface of the furnace body, a connecting cavity is formed in the interior of the fixed block, an exhaust hole is formed in the inner wall of the connecting cavity, a communication section is formed at the communication position of the first combustion chamber and the second combustion chamber, an exhaust passage is formed in the inner wall of the communication section and communicates with the exhaust hole, the inner diameter of the exhaust passage at the opening is larger than the inner diameter of the exhaust hole, and the inner diameter of the exhaust passage gradually decreases with the distance from the exhaust hole until the inner diameter of the exhaust passage is equal to and communicates with the inner diameter of the exhaust hole.

[0005] In the above technical scheme, preferably, the inner wall of the connecting cavity is slidingly connected with an adjusting ring, the surface of the adjusting ring is provided with uniformly distributed air holes, a spring is fixedly connected between the bottom of the adjusting ring and the inner wall of the connecting cavity, and the top of the adjusting ring is fixedly connected with a connecting column corresponding to the exhaust hole.

[0006] In the above technical scheme, preferably, the inner wall of the exhaust hole is fixedly connected with a mounting ring, the inner diameter of the mounting ring is greater than the diameter of the connecting column, the upper end of the connecting column penetrates through the mounting ring and is fixedly connected with a connecting plate, and the surface of the connecting plate is provided with annularly distributed connecting holes.

[0007] In the above technical scheme, preferably, the inner wall of the connecting section is fixedly connected with a flow guide shell, the inner side of the flow guide shell forms a drainage section, and the opening height of the exhaust passage is lower than the setting height of the flow guide shell.

[0008] In the above technical scheme, preferably, the surface of the furnace body is fixedly connected with a fixed shell, the surface of the fixed shell is provided with an import groove in communication with the second combustion cavity, the inner side wall of the import groove is arranged in the tangential direction of the fixed shell, the inner wall of the fixed shell is rotatably connected with a rotating ring, the bottom of the rotating ring is provided with an electric push rod, the output shaft of the electric push rod is ball-hinged with a push rod, and the upper end of the push rod is rotatably connected with the bottom of the rotating ring.

[0009] In the above technical scheme, preferably, the top of the rotating ring is fixedly connected with uniformly distributed mounting columns, the surface of the mounting column is rotatably connected with an adjusting rod, the inner wall of the import groove is provided with an adjusting blade, one side of the adjusting blade is tightly attached to one inner side wall of the import groove, one end of the adjusting blade penetrates through the import groove and is rotatably connected with the inner top wall of the fixed shell, the other end of the adjusting rod is hinged with a sliding seat, and the surface of the sliding seat is slidingly connected with the adjusting blade.

[0010] In the above technical scheme, preferably, the surface of the fixed shell is provided with a shunt pipe, the shunt pipe is in a U shape, the other end of the shunt pipe is in communication with the connecting cavity, and a secondary air injection pipe is in communication with the middle of the surface of the shunt pipe.

[0011] In the above technical scheme, preferably, the first air inlet assembly comprises an air inlet pipe in communication with the first combustion cavity, the other end of the air inlet pipe is in communication with a mounting shell, the other end of the mounting shell is in communication with a converging pipe, and the other end of the converging pipe is in communication with an import pipe for importing primary air and coal powder.

[0012] In the above technical scheme, preferably, the inner wall of the mounting shell is fixedly connected with uniformly distributed mounting plates, the surface of the mounting plate is provided with uniformly distributed through holes, and the through holes provided on the surfaces of two adjacent mounting plates are arranged alternately.

[0013] Compared with the prior art, the present application has the following beneficial effects: By setting the second air inlet assembly, an air film protection can be formed in the communication section of the first combustion chamber and the second combustion chamber. The air film not only cools the wall surface, but also physically prevents the molten ash from contacting the furnace wall, thereby preventing the adhesion and accumulation of the ash in this area, fundamentally reducing the risk of slagging, and ensuring the long-term continuous and stable operation of the boiler.

[0014] By setting the second air inlet assembly, a rotating air flow can be formed in the second combustion chamber, which enhances the mixing intensity of air and combustible gas, ensures the complete combustion of the pulverized coal, and uses the centrifugal force generated by the rotating air flow to drive the unburned ash particles to stay in the combustion zone for further reaction, so as to promote the molten ash to gather, aggregate and grow towards the center high-temperature area of the furnace, and finally overcome the centrifugal force under the action of gravity and fall into the bottom funnel-shaped recovery pipe to be efficiently discharged.

[0015] By setting the first air inlet assembly, the pulverized coal and the primary air can be well mixed. The use of the converging section reduces the pressure and increases the kinetic energy, so as to break up the coal powder clusters. After entering the inside of the installation shell, the air flow passes through the through holes on the installation plates in turn. Due to the staggered arrangement of the through holes on the surfaces of two adjacent installation plates, the air flow is cut and mixed multiple times, which improves the mixing effect and is beneficial to subsequent ignition. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a structural schematic view of the present application; Figure 2 is a sectional view of the present application; Figure 3 is a schematic view of the opening of the guide groove of the present application; Figure 4 is a schematic view of the distribution of the through holes of the present application; Figure 5 is a schematic view of the connection of the electric push rod and the rotating ring of the present application; Figure 6 is a schematic view of the distribution of the installation ring, the connecting column and the connecting plate of the present application; Figure 7 is a structural schematic view of the guide shell of the present application; Figure 8 is a schematic view of the distribution of the exhaust holes and the exhaust passages of the present application.

[0017] In the diagram: 1. Furnace body; 101. Plasma igniter; 102. First combustion chamber; 103. Second combustion chamber; 2. Recovery pipe; 3. First air intake assembly; 301. Air intake pipe; 302. Mounting shell; 303. Contraction pipe; 304. Inlet pipe; 305. Through hole; 306. Mounting plate; 4. Second air intake assembly; 401. Inlet groove; 402. Flow guide shell; 403. Adjusting ring; 404. Vent hole; 405. Spring; 406. Fixed shell; 407. Electric push rod; 408. Adjusting blade; 409. Adjusting rod; 410. Mounting column; 411. Connecting hole; 412. Connecting plate; 413. Mounting ring; 414. Connecting column; 415. Flow guide section; 416. Exhaust hole; 417. Exhaust channel; 418. Fixing block; 419. Rotating ring. Detailed Implementation

[0018] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] Numerous specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the invention is not limited to the specific embodiments disclosed below.

[0020] like Figures 1-8 The plasma burner shown includes a furnace body 1. A second combustion chamber 103 is provided on the top of the furnace body 1. A first combustion chamber 102 is provided inside the furnace body 1 and communicates with the second combustion chamber 103. A plasma igniter 101 is provided at the lower end of the surface of the furnace body 1. One end of the plasma igniter 101 extends into the interior of the first combustion chamber 102. A recovery pipe 2 is provided inside the second combustion chamber 103. The lower end of the recovery pipe 2 passes through the furnace body 1. A first air intake assembly 3 is provided on the surface of the furnace body 1. A second air intake assembly 4 is provided on the surface of the furnace body 1 above the first air intake assembly 3. The upper end of the recovery pipe 2 is funnel-shaped. The second air intake assembly 4 includes a fixing block 418 fixedly connected to the surface of the furnace body 1. The fixing block 418 has a connecting cavity inside, and the inner wall of the connecting cavity has an exhaust hole 416. The connection between the first combustion chamber 102 and the second combustion chamber 103 forms a connecting section. The inner wall of the connecting section has an exhaust channel 417 that communicates with the exhaust hole 416. The inner diameter of the opening of the exhaust channel 417 is larger than the inner diameter of the exhaust hole 416. The inner diameter of the exhaust channel 417 gradually decreases as the distance to the exhaust hole 416 decreases until it is equal to the inner diameter of the exhaust channel 417 and they are connected.

[0021] The recovery pipe 2 is used to recover the ash and slag produced after combustion in the furnace body 1. The plasma igniter 101 is a relatively mature technical component in existing applications, and will not be described in detail here.

[0022] As Figures 1-8 shown, the inner wall of the connecting cavity is slidingly connected with an adjusting ring 403, the surface of the adjusting ring 403 is provided with uniformly distributed air holes 404, the bottom of the adjusting ring 403 is fixedly connected with a spring 405 between the inner wall of the connecting cavity, and the top of the adjusting ring 403 is fixedly connected with a connecting column 414 corresponding to the exhaust hole 416.

[0023] The inner wall of the exhaust hole 416 is fixedly connected with a mounting ring 413, the inner diameter of the mounting ring 413 is greater than the diameter of the connecting column 414, the upper end of the connecting column 414 penetrates through the mounting ring 413 and is fixedly connected with a connecting plate 412, and the surface of the connecting plate 412 is provided with annularly distributed connecting holes 411.

[0024] The inner wall of the communication section is fixedly connected with a flow guide shell 402, the inner side of the flow guide shell 402 forms a drainage section 415, and the opening height of the exhaust passage 417 is lower than the setting height of the flow guide shell 402.

[0025] After the secondary air is shunted, part of it is introduced into the inside of the connecting cavity, and due to the setting of the spring 405, the secondary air in the connecting cavity needs to overcome the elastic force of the spring 405 to pass through the air holes 404, and due to the fact that the inner diameter of the mounting ring 413 is greater than the inner diameter of the connecting column 414, the gap therebetween can push the connecting plate 412 to move upward, so that the connecting plate 412 is separated from the mounting ring 413 and then passes through the connecting holes 411 to pass through the exhaust hole 416 and finally passes through the exhaust passage 417 to be discharged. Due to the setting of the spring 405, the secondary air entering the inside of the connecting cavity needs to lift the mounting ring 413 before the connecting plate 412 and the mounting ring 413 are separated, which can ensure that the air pressure of the air flow discharged through the exhaust passage 417 is equal, thereby achieving the purpose of uniform discharge. The discharged air flow can be driven to form an air film along the inner wall of the furnace body 1 under the action of the drainage section 415 in the inner side of the flow guide shell 402, thereby reducing the adhesion of the ash formed by the incomplete combustion in the first combustion cavity 102 to the inner wall of the furnace body 1 after the ash enters the second combustion cavity 103 with the primary air, and affecting the subsequent combustion in the second combustion cavity 103.

[0026] As Figures 1-8 shown, the surface of the furnace body 1 is fixedly connected with a fixed shell 406, the surface of the fixed shell 406 is provided with a guide slot 401 communicating with the second combustion cavity 103, the inner side wall of the guide slot 401 is arranged in the tangential direction of the fixed shell 406, the inner wall of the fixed shell 406 is rotatably connected with a rotating ring 419, the bottom of the rotating ring 419 is provided with an electric push rod 407, the output shaft of the electric push rod 407 is ball-hinged with a push rod, and the upper end of the push rod is rotatably connected with the bottom of the rotating ring 419.

[0027] The top of the rotating ring 419 is fixedly connected with uniformly distributed mounting columns 410, the surface of the mounting column 410 is rotationally connected with an adjusting rod 409, the inner wall of the guide-in groove 401 is provided with an adjusting blade 408, one side of the adjusting blade 408 is in close contact with an inner side wall of the guide-in groove 401, one end of the adjusting blade 408 penetrates through the guide-in groove 401 and is rotationally connected with the inner top wall of the fixed shell 406, the other end of the adjusting rod 409 is hingedly connected with a sliding seat, and the sliding seat is slidingly connected with the surface of the adjusting blade 408.

[0028] The surface of the fixed shell 406 is provided with a shunt pipe, the shunt pipe is in a U shape, the other end of the shunt pipe is in communication with the connecting cavity, and the surface of the shunt pipe is in communication with a secondary air injection pipe at the middle part.

[0029] The secondary air injection pipe is used for guiding the secondary air to be introduced and respectively introduced into the connecting cavity and the interior of the fixed shell 406 through the shunt pipe; By starting the electric push rod 407, the rotating ring 419 can be driven to rotate, and then the adjusting rod 409 is driven to adjust the position of the adjusting blade 408 under the action of the mounting column 410, so that the injection angle of the secondary air is changed by tilting, and specifically, the injection angle is adjustable in the range of 40°-60°, and the burning effect in the second combustion cavity 103 can be changed according to actual conditions.

[0030] After the secondary air enters the interior of the fixed shell 406, it can enter the interior of the second combustion cavity 103 along the tangential direction of the furnace body 1 through the guide-in groove 401, and in this process, a rotating upward airflow can be formed, so that the secondary air is extremely fully mixed with the air, ensuring complete combustion of the pulverized coal, and in this process, lighter ash can be gathered to the center under the action of centrifugal force to form larger ash, and then the larger ash can overcome the centrifugal force and fall downward under the action of gravity to be discharged through the recovery pipe 2, and the funnel-shaped arrangement of the upper end of the recovery pipe 2 can better collect the ash, and the residence and accumulation in the furnace are minimized.

[0031] As shown in the figure, Figures 1-8 The first air inlet assembly 3 includes an air inlet pipe 301 in communication with the first combustion cavity 102, the other end of the air inlet pipe 301 is in communication with a mounting shell 302, the other end of the mounting shell 302 is in communication with a converging pipe 303, and the other end of the converging pipe 303 is in communication with a guide-in pipe 304 for guiding the primary air and the pulverized coal.

[0032] The inner wall of the mounting shell 302 is fixedly connected with uniformly distributed mounting plates 306, the surface of the mounting plate 306 is provided with uniformly distributed through holes 305, and the through holes 305 provided on the surfaces of two adjacent mounting plates 306 are arranged in a staggered manner; The arrangement of the first air inlet assembly 3 can accelerate the airflow when the pulverized coal and primary air enter the converging pipe 303, so that the pressure is reduced, the kinetic energy is increased, the coal lumps are broken up, and then the pulverized coal passes through the through holes 305 on the mounting plates 306 in sequence, and due to the staggered arrangement of the through holes 305 on the surfaces of two adjacent mounting plates 306, the mixing effect is improved through multiple cutting and mixing, which is beneficial to subsequent ignition.

[0033] Working principle: The pulverized coal and primary air are introduced into the interior of the first combustion chamber 102 through the first air inlet assembly 3 and ignited by the plasma igniter 101. In this process, the pulverized coal and primary air are fully mixed to facilitate ignition. After preliminary combustion, they enter the interior of the second combustion chamber 103 for full combustion. In this process, the second air inlet assembly 4 can reduce the adhesion and residue of ash in the furnace body 1, avoid the adhesion of ash in the furnace body 1 affecting the subsequent combustion effect, and form a gas film protection connecting section under the action of the second air inlet assembly 4 to avoid the adhesion of ash during the process of entering the interior of the second combustion chamber 103, reduce the processing difficulty, and the secondary air enters the interior of the fixed shell 406 and then enters the interior of the second combustion chamber 103 along the tangential direction of the furnace body 1 through the introduction groove 401. In this process, a rotating upward airflow is formed, which can mix the secondary air and air extremely fully, ensure the complete combustion of the pulverized coal, and in this process, the lighter ash can be gathered to the center under the centrifugal force to form larger ash and then fall downward under the action of gravity to be discharged through the recovery pipe 2. The funnel-shaped arrangement of the upper end of the recovery pipe 2 can better collect the ash and maximize the reduction of residence and accumulation in the furnace.

[0034] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above embodiments, and the above embodiments and descriptions in the specification are only the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection claimed by the present application is defined by the appended claims and their equivalents.

Claims

1. A plasma burner, comprising a furnace body (1), characterized in that, The furnace body (1) has a second combustion chamber (103) at the top and a first combustion chamber (102) connected to the second combustion chamber (103) inside. A plasma igniter (101) is provided at the lower end of the surface of the furnace body (1), and one end of the plasma igniter (101) extends into the interior of the first combustion chamber (102). A recovery pipe (2) is provided inside the second combustion chamber (103), and the lower end of the recovery pipe (2) passes through the furnace body (1). A first air intake assembly (3) is provided on the surface of the furnace body (1), and a second air intake assembly (4) is provided on the surface of the furnace body (1) above the first air intake assembly (3). The upper end of the recovery pipe (2) is funnel-shaped. The second air intake assembly (4) includes a fixing block (418) fixedly connected to the surface of the furnace body (1). The fixing block (418) has a connecting cavity inside, and the inner wall of the connecting cavity has an exhaust hole (416). The connection between the first combustion chamber (102) and the second combustion chamber (103) forms a connecting section. The inner wall of the connecting section has an exhaust channel (417) connected to the exhaust hole (416). The inner diameter of the opening of the exhaust channel (417) is larger than the inner diameter of the exhaust hole (416). The inner diameter of the exhaust channel (417) gradually decreases as the distance to the exhaust hole (416) decreases until it is equal to and connected to the inner diameter of the exhaust channel (417).

2. The plasma burner according to claim 1, characterized in that, An adjusting ring (403) is slidably connected to the inner wall of the connecting cavity. The surface of the adjusting ring (403) is provided with evenly distributed vent holes (404). A spring (405) is fixedly connected between the bottom of the adjusting ring (403) and the inner wall of the connecting cavity. A connecting post (414) corresponding to the exhaust hole (416) is fixedly connected to the top of the adjusting ring (403).

3. The plasma burner according to claim 2, characterized in that, An installation ring (413) is fixedly connected to the inner wall of the exhaust hole (416). The inner diameter of the installation ring (413) is larger than the diameter of the connecting column (414). The upper end of the connecting column (414) passes through the installation ring (413) and is fixedly connected to a connecting plate (412). The surface of the connecting plate (412) is provided with annularly distributed connecting holes (411).

4. The plasma burner according to claim 3, characterized in that, The inner wall of the connecting section is fixedly connected to a flow guide shell (402), and a flow guide section (415) is formed on the inner side of the flow guide shell (402). The opening height of the exhaust channel (417) is lower than the setting height of the flow guide shell (402).

5. The plasma burner according to claim 4, characterized in that, A fixed shell (406) is fixedly connected to the surface of the furnace body (1). The surface of the fixed shell (406) is provided with an inlet groove (401) that communicates with the second combustion chamber (103). The inner wall of the inlet groove (401) is tangential to the fixed shell (406). A rotating ring (419) is rotatably connected to the inner wall of the fixed shell (406). An electric push rod (407) is provided at the bottom of the rotating ring (419). The output shaft of the electric push rod (407) is ball-jointed with a push rod. The upper end of the push rod is rotatably connected to the bottom of the rotating ring (419).

6. The plasma burner according to claim 5, characterized in that, The top of the rotating ring (419) is fixedly connected with uniformly distributed mounting columns (410), and the surface of the mounting columns (410) is rotatably connected with an adjusting rod (409). The inner wall of the guide groove (401) is provided with an adjusting blade (408), and one side of the adjusting blade (408) is in close contact with one inner side wall of the guide groove (401). One end of the adjusting blade (408) passes through the guide groove (401) and is rotatably connected to the inner top wall of the fixed shell (406). The other end of the adjusting rod (409) is hinged with a sliding seat, and the sliding seat is slidably connected to the surface of the adjusting blade (408).

7. The plasma burner according to claim 6, characterized in that, The surface of the fixed shell (406) is provided with a diversion pipe, which is U-shaped. The other end of the diversion pipe is connected to the connecting cavity, and a secondary air injection pipe is connected to the middle of the surface of the diversion pipe.

8. The plasma burner according to claim 1, characterized in that, The first air intake assembly (3) includes an air intake pipe (301) connected to the first combustion chamber (102), the other end of the air intake pipe (301) is connected to a mounting shell (302), the other end of the mounting shell (302) is connected to a shrink tube (303), and the other end of the shrink tube (303) is connected to an inlet tube (304) for introducing primary air and pulverized coal.

9. The plasma burner according to claim 8, characterized in that, The inner wall of the mounting shell (302) is fixedly connected with uniformly distributed mounting plates (306), and the surface of the mounting plates (306) is provided with uniformly distributed through holes (305), and the through holes (305) on the surfaces of two adjacent mounting plates (306) are staggered.

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