A combustion system

Abstract

The present invention discloses a combustion system, which is suitable for a rotary kiln. The rotary kiln comprises: a kiln body is provided with a first cavity, the first cavity is used to contain fuel and combustion products; a kiln head cover, the kiln head cover is provided at one end of the kiln body, and the kiln head cover is provided with a second cavity connected to the first cavity; the combustion system comprises: a burner body can move toward the first cavity or away from the first cavity, so that the burner body is in a first state and a second state; a bellows, the bellows is provided on the side of the kiln head cover away from the kiln body, and surrounds the burner body; in the first state, the burner body passes through the bellows and the second cavity and part of the burner body is located in the first cavity, so that the temperature of the combustion product is at the first temperature; in the second state, the burner body passes through the bellows and is located outside the second cavity, and the bellows supplies air into the kiln head cover, so that the temperature of the combustion product is at the second temperature, and the second temperature is lower than the first temperature. The present invention can have both a calcination mode and a hot air roasting mode.

Description

Technical Field

[0001] The invention relates to the field of machinery, and in particular to a combustion system. Background Art

[0002] In the process of calcining minerals in a rotary kiln, the temperature requirements for calcining vary due to the different quality and characteristics of the raw materials. For example, for materials that need to react between 1000 and 1500 degrees Celsius, thermal radiation in the rotary kiln is usually used as the main heating method (i.e., calcination mode), which often requires the shape and size of the flame to be adjusted to suit different material requirements. For materials with a reaction temperature below 1000 degrees Celsius, the impact of thermal radiation should be reduced, and more reliance should be placed on direct contact with hot air (thermal convection) for roasting (i.e., hot air roasting mode).

[0003] In view of this, we urgently need a combustion system that can flexibly switch between these two working modes in order to meet the calcination needs of various materials more efficiently and accurately. Summary of the invention

[0004] The purpose of the present invention is to provide a combustion system having both a calcining mode and a hot air roasting mode. The present invention provides a combustion system having both a calcining mode and a hot air roasting mode.

[0005] In order to solve the above technical problems, the embodiment of the present invention discloses a combustion system, which is applicable to a rotary kiln, wherein the rotary kiln comprises: a kiln body, wherein the kiln body is provided with a first cavity, wherein the first cavity is used to contain fuel and combustion products; a kiln head cover, wherein the kiln head cover is provided at one end of the kiln body, wherein the kiln head cover is provided with a second cavity connected to the first cavity; the combustion system comprises:

[0006] a burner body, the burner body being movable toward the first cavity or away from the first cavity so that the burner body is in a first state and a second state;

[0007] A wind box, the wind box is arranged on a side of the kiln head cover away from the kiln body and surrounds the burner body;

[0008] In the first state, the burner body passes through the wind box and the second cavity and a portion of the burner body is located in the first cavity, so that the temperature of the combustion products is at a first temperature;

[0009] In the second state, the burner body passes through the wind box and is located outside the second cavity, and the wind box supplies air into the kiln head hood to make the temperature of the combustion product at a second temperature, which is lower than the first temperature.

[0010] By adopting the above technical solution, the burner body is used to move toward the first cavity so that the burner body is in a first state. In the first state, the burner body passes through the wind box and the second cavity, and a part of the burner body is located in the first cavity. At this time, the fuel flame is in the first cavity, and the wind introduced into the burner body can stir the volume of fuel and oxygen in the first cavity, so that the mixing time point and mixing ratio of the fuel and oxygen in the first cavity can be controlled. For example, more wind can be introduced to advance the mixing time point of fuel and oxygen or more gas can be introduced to increase the temperature of the combustion product so that it is at a first temperature, for example, 1000°C to 1500°C.

[0011] In the second state, the burner body passes through the bellows and is located outside the second cavity, and the bellows supplies air to the kiln head hood. At this time, the fuel flame is in the second cavity, and the wind introduced into the burner body can stir the volume of fuel and oxygen in the second cavity, so as to control the mixing time and mixing ratio of the fuel and oxygen in the second cavity, for example, delaying the mixing time of the fuel and oxygen or introducing less fuel gas, thereby reducing the temperature of the combustion products. At the same time, the bellows can provide additional cold air to the second cavity, thereby reducing the temperature of the combustion products in the second cavity to a second temperature, for example, less than 1000°C.

[0012] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, in which in the first state, the length of the portion of the burner body located in the first cavity is 1m-1.5m, and in the second state, the distance of the burner body outside the second cavity is 0mm-500mm.

[0013] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, the bellows includes a snap-on portion and an air supply portion, the air supply portion is arranged at the outer periphery of the snap-on portion, and is used to supply air to the kiln head hood, and the snap-on portion surrounds the burner body.

[0014] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, wherein the burner body is provided with a plurality of channels, the plurality of channels are radially spaced apart, and one or more of the plurality of channels are capable of axially moving so that the temperature of the combustion products is at the first temperature or the second temperature.

[0015] By adopting the above technical solution, one or more of the multiple channels are used to move axially to change their length in the first cavity, change the outlet velocity and outlet direction of the output of each channel, control the mixing time and efficiency of air and fuel, and thus control the temperature of the flame to reach the first temperature or the second temperature.

[0016] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, wherein along the center to the outside direction of the burner body, the multiple channels sequentially include a central wind channel, a gas channel and an axial wind channel, the axial wind channel includes an axial wind inner pipe and an axial wind outer pipe, the axial wind inner pipe is used to move axially relative to the axial wind outer pipe, and the gas channel includes a gas inner pipe, and the gas inner pipe is used to move along the axial direction relative to the axial wind inner pipe.

[0017] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, wherein the length of the axial wind inner tube used to move along the axial direction relative to the axial wind outer tube is -20mm-100mm, and the length of the gas inner tube used to move along the axial direction relative to the axial wind inner tube is 0mm-40mm.

[0018] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, wherein along the direction from the center to the outside of the burner body, the multiple channels sequentially include a center wind channel, a pulverized coal channel, a gas channel, a rotational wind channel and an axial wind channel, the axial wind channel includes an axial wind inner pipe and an axial wind outer pipe, the axial wind inner pipe is used to move axially relative to the axial wind outer pipe, the rotational wind channel includes a rotational wind inner pipe, the rotational wind inner pipe is used to move axially relative to the axial wind inner pipe, the gas channel includes a gas inner pipe, the gas inner pipe is used to move axially relative to the rotational wind inner pipe, and the center wind channel includes a center wind inner pipe, the center wind inner pipe is used to move axially relative to the gas inner pipe.

[0019] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, wherein the length of the axial wind inner tube used to move along the axial direction relative to the axial wind outer tube is -20mm-100mm, the length of the rotary wind inner tube used to move along the axial direction relative to the axial wind inner tube is 0mm-40mm, the length of the gas inner tube used to move along the axial direction relative to the rotary wind inner tube is 0mm-40mm, and the length of the central wind inner tube used to move along the axial direction relative to the gas inner tube is -10mm-20mm.

[0020] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, wherein along the direction from the center of the burner body to the outside, the multiple channels sequentially include a center wind channel, a coal powder channel, a rotational wind channel and an axial wind channel, the axial wind channel includes an axial wind inner pipe and an axial wind outer pipe, the axial wind inner pipe is used to move axially relative to the axial wind outer pipe, the rotational wind channel includes a rotational wind inner pipe, the rotational wind inner pipe is used to move along the axial direction relative to the axial wind inner pipe, the center wind channel includes a center wind inner pipe, the center wind inner pipe is used to move along the axial direction relative to the rotational wind inner pipe.

[0021] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, wherein the length of the axial wind inner tube used to move along the axial direction relative to the axial wind outer tube is -20mm-100mm, the length of the rotary wind inner tube used to move along the axial direction relative to the axial wind inner tube is 0mm-40mm, and the length of the central wind inner tube used to move along the axial direction relative to the rotary wind inner tube is -10mm-20mm.

[0022] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, wherein the central wind channel includes an igniter channel, a central gas gun channel and at least one flame detector channel, and the igniter channel, the central gas gun channel and the at least one flame detector channel are arranged at intervals along the circumferential direction and are located inside the central wind channel.

[0023] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, wherein the head of the rotary wind inner tube is provided with a plurality of grooves, the grooves are arranged at intervals along the circumferential direction, and the angle of each groove is 0°-40°.

[0024] According to another specific embodiment of the present invention, an embodiment of the present invention discloses a combustion system, wherein a swirl device is provided in the wind box, and the swirl device includes a plurality of swirl fins arranged at intervals along the circumferential direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram showing the structure of a burner system provided by an embodiment of the present invention is shown;

[0026] Figure 2 A cross-sectional view showing a first type of multiple channels in a burner body provided by an embodiment of the present invention;

[0027] Figure 3 A schematic diagram showing a first structure of multiple channels in a burner body provided by an embodiment of the present invention;

[0028] Figure 4A second cross-sectional view showing a plurality of channels in a burner body provided by an embodiment of the present invention;

[0029] Figure 5 A third cross-sectional view showing a plurality of channels in a burner body provided by an embodiment of the present invention;

[0030] Figure 6 A schematic structural diagram showing the front end of the rotary wind inner tube provided in an embodiment of the present invention;

[0031] Figure 7 A three-dimensional diagram showing a bellows provided by an embodiment of the present invention;

[0032] Figure 8 A cross-sectional view of a bellows provided by an embodiment of the present invention is shown;

[0033] Fig. 9 Show Figure 8 Magnified view of area D in the middle.

[0034] Among them, the figure numerals are: 100, kiln body; 101, first cavity; 200, kiln head cover; 201, second cavity; 300, burner body; 301, central wind channel; 302, coal powder channel; 303, gas channel; 304, cyclone wind channel; 305, axial wind channel; 306, axial wind outer pipe; 307, axial wind inner pipe; 308, cyclone wind inner pipe; 309, gas inner pipe; 310, central wind inner pipe; 311, inner wall of axial wind outer pipe; 312, outer wall of axial wind inner pipe; 313, outer wall of cyclone wind inner pipe; 314, outer wall of central wind inner pipe; 315, swirl sheet; 3 16. Igniter channel; 317. Central gas gun channel; 318. Flame detector channel; 400. Bellows; 401. Buckle; 402. Air supply; 403. Swirl device; 404. Swirl fin; 405. First bolt; 406. First sealing packing; 407. First half flange; 408. Second bolt; 409. Second half flange; 410. Press plate; 411. Third bolt; 412. Gasket; 413. Second sealing packing; 414. Third sealing packing; 415. Inlet flange; 416. Fixed flange; 500. Expansion joint; 501. Jack; 600. Trolley. DETAILED DESCRIPTION

[0035] The following specific embodiments illustrate the implementation of the present invention, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this implementation. On the contrary, the purpose of introducing the invention in conjunction with the implementation is to cover other options or modifications that may extend based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0036] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0037] In the description of this embodiment, it should be noted that the terms "upper", "lower", "inner", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0038] The terms “first”, “second”, etc. are only used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0039] In the description of this embodiment, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this embodiment can be understood according to specific circumstances.

[0040] To make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0041] The embodiment of the present application discloses a combustion system, which can be applied to rotary kiln processes such as lithium carbonate, limestone, pellets, kaolin, titanium dioxide, etc., but is not limited thereto. As long as the rotary kiln process requires both a calcination mode of 1000°C to 1500°C and a hot air roasting mode below 1000°C, the combustion system provided in the embodiment of the present application can be applied. The application in the lithium carbonate process is used as an example for explanation.

[0042] For example, reference Figure 1 The combustion system is suitable for a rotary kiln, and the rotary kiln includes: a kiln body 100 and a kiln head cover 200. The kiln body 100 is provided with a first cavity 101, and the first cavity 101 is used to contain materials (such as the above-mentioned lithium carbonate, limestone, pellets, kaolin, titanium dioxide, etc.) and combustion products (such as nitrogen, carbon dioxide, water, etc.). The first cavity 101 rotates counterclockwise or clockwise at a low speed to turn over the materials in the first cavity 101. The kiln head cover 200 is arranged at one end of the kiln body 100, and the kiln head cover 200 is provided with a second cavity 201 connected to the first cavity 101. The second cavity 201 is used to transfer the calcined / roasted materials to the next process (such as acidification) and provide the space required for combustion in the roasting mode. Exemplarily, in the radial direction, a conveying pipe is provided at the lower end of the second cavity 201, which can convey the combustion products to the next process.

[0043] Exemplarily, the combustion system includes: a burner body 300 and a bellows 400, the burner body 300 is used to move toward the first cavity 101 or away from the first cavity 101, so that the burner body 300 is in a first state and a second state; the bellows 400 is arranged on the side of the kiln head hood 200 away from the kiln body 100, and surrounds the burner body 300, in the first state, the burner body 300 passes through the bellows 400 and the second cavity 201 and a part of the burner body 300 (i.e., the head of the burner body 300) is located in the first cavity 101, so that the temperature of the combustion product is at a first temperature; in the second state, the burner body 300 passes through the bellows 400 and the head of the burner body 300 is located outside the second cavity 201, and the bellows 400 supplies air into the kiln head hood 200, so that the temperature of the combustion product is at a second temperature, and the second temperature is lower than the first temperature.

[0044] By adopting the above technical solution, the burner body 300 is used to move toward the first cavity 101 so that the burner body 300 is in a first state. In the first state, the burner body 300 passes through the bellows 400 and the second cavity 201, and a part of the burner body 300 is located in the first cavity 101. At this time, the fuel flame is in the first cavity 101, so that the mixing time point and mixing ratio of the fuel and oxygen in the first cavity 101 can be controlled, for example, the mixing time point of the fuel and oxygen can be advanced or the amount of fuel gas can be increased, thereby increasing the temperature of the combustion product so that it is at a first temperature, for example, 1000°C to 1500°C.

[0045] In the second state, the burner body 300 passes through the bellows 400 and is located outside the second cavity 201, and the bellows 400 supplies air into the kiln head hood 200. At this time, the fuel flame is in the second cavity 201, so that the mixing time and mixing ratio of the fuel and oxygen in the second cavity 201 can be controlled, for example, the mixing time of the fuel and oxygen can be delayed or the amount of fuel gas can be reduced, thereby reducing the temperature of the combustion products. At the same time, the bellows 400 can provide cold air into the second cavity 201, thereby reducing the temperature of the combustion products in the second cavity 201 to a second temperature, for example, less than 1000°C.

[0046] That is to say, the embodiment of the present application controls the mixing time and mixing ratio of the fuel and oxygen by changing the position of the burner body 300, thereby controlling the temperature of the combustion products so that they reach the two states as described above, namely the first state (also called the calcination mode) and the second state (also called the hot air roasting mode).

[0047] Exemplarily, a trolley 600 is provided at the bottom of the burner body 300 , and the burner body 300 can be moved by the trolley 600 , so that the position of the burner body 300 can be changed.

[0048] For example, in the first state (i.e., the cart 600 is located Figure 1 The position of the solid line in the middle, so that the burner body 300 is located in the first cavity 101), the length of the portion of the burner body 300 located in the first cavity 101 (ie Figure 1 L1) is 1m-1.5m, for example, 1m, 1.2m, 1.25m, 1.36m, 1.5m, etc., that is, the front end of the burner body 300 is located at Figure 1 Point B shown in the second state (i.e., the cart 600 is located at Figure 1 The distance between the burner body 300 and the second cavity 201 is 0 mm to 500 mm, for example, 0 mm, 52 mm, 150 mm, 300 mm, 500 mm, etc., that is, the front end of the burner body 300 is located at Figure 1 Point A shown.

[0049] For example, reference Figures 2 to 5 The burner body 300 is provided with a plurality of channels, for example, the central air channel 301, the gas channel 303 and the axial air channel 305 (i.e. Figure 5 The state shown) or the central wind channel 301, the coal powder channel 302, the gas channel 303, the rotary wind channel 304 and the axial wind channel 305 (i.e. Figure 2 The state shown in the figure) is selected according to the different fuels. The embodiment of the present application does not limit the number and type of channels of the burner body 300.

[0050] For example, in combination Figure 1 , multiple channels along the radial direction (i.e. Figure 2 The X direction shown in the figure) is arranged at intervals, and one or more of the multiple channels can be arranged along the axial direction (i.e. Figure 2 The combustion product is moved in the Y direction (as shown) so that the temperature of the combustion product is at the first temperature or the second temperature.

[0051] For example, in combination Figure 1 The portion of the burner body 300 outside the second cavity 201 is provided with an expansion joint 500 and a jack 501, and the jack 501 is used to push one or more channels of the burner body 300 in the axial direction (i.e. Figure 2 Y direction) movement.

[0052] refer to Figure 5 Combined with Figure 1 When the channels of the burner include the central wind channel 301, the gas channel 303 and the axial wind channel 305, the central wind channel 301, the gas channel 303 and the axial wind channel 305 are sequentially arranged along the center of the burner body 300 to the outside direction (i.e. Figure 5 The axial wind channel 305 includes an axial wind inner tube 307 and an axial wind outer tube 306. The axial wind inner tube 307 is used to move axially relative to the axial wind outer tube 306. The gas channel 303 includes a gas inner tube 309. The gas inner tube 309 is used to move axially relative to the axial wind inner tube 307.

[0053] Among them, the inner wall 311 of the axial wind outer tube and the outer wall 312 of the axial wind inner tube jointly form the axial wind channel 305, the inner wall of the axial wind inner tube 307 and the outer wall of the gas inner tube 309 jointly form the gas channel 303, and the inner wall of the gas inner tube 309 surrounds the central wind channel 301.

[0054] Combination Figure 1 and Figure 2 , taking the front end of the axial wind outer pipe 306 20 mm axially backward as the reference line (i.e. Figure 5 In the EF segment shown in the figure), the length of the axial wind inner tube 307 for axial movement relative to the axial wind outer tube 306 is -20mm-100mm, that is, the axial wind inner tube 307 can be moved to be flush with the front end of the axial wind outer tube 306, that is, -20mm, or it can be moved from a position flush with the front end of the axial wind outer tube 306 to a distance of 120mm therefrom, that is, 100mm.

[0055] Similarly, the length of the gas inner tube 309 for axial movement relative to the axial wind inner tube 307 is 0 mm-40 mm. In other words, the gas inner tube 309 can move to be flush with the front end of the axial wind inner tube 307, that is, 0 mm, or can move from the position flush with the front end of the axial wind inner tube 307 to a distance of 40 mm therefrom.

[0056] Among them, the inner wall 311 of the axial wind outer tube gradually starts to change its diameter at 100 mm from the front end of the axial wind outer tube 306 along the axial direction, and the diameter changes from large to small, and stops changing its diameter at 140 mm from the front end of the axial wind outer tube 306 along the axial direction, that is, from 100 mm to 140 mm from the front end of the axial wind outer tube 306 along the axial direction, the inner wall 311 of the axial wind outer tube has a gradually shrinking structure, that is, along the axial direction, it has a structure that is wide at the front and narrow at the back, that is, it has a certain slope here. The diameter remains unchanged at 140 mm to 200 mm from the front end of the axial wind outer tube 306 along the axial direction, and gradually starts to change its diameter at 200 mm from the front end of the axial wind outer tube 306 along the axial direction, and the diameter changes from small to large.

[0057] The outer wall 312 of the axial wind inner tube gradually starts to change in diameter at a distance of 20 mm in the axial direction from the front end of the axial wind inner tube 307, and the diameter changes from large to small, and stops changing in diameter at a distance of 80 mm in the axial direction from the front end of the axial wind inner tube 307, that is, from 20 mm to 80 mm in the axial direction from the front end of the axial wind inner tube 307, the outer wall 312 of the axial wind inner tube has a tapered structure, that is, along the axial direction, it has a structure that is wide in the front and narrow in the back, that is, it has a certain slope.

[0058] In other words, the axial wind channel 305 formed by the inner wall 311 of the axial wind outer tube and the outer wall 312 of the axial wind inner tube is a variable diameter channel, that is, when the axial wind enters the first cavity 101 of the kiln body 100 from the axial wind channel 305, due to the influence of the variable diameter of the axial wind channel 305, the amount and speed of the axial wind entering the first cavity are changed, so as to adjust and control the temperature of the combustion products in the first cavity, so that the temperature of the combustion products is converted between the first temperature or the second temperature or maintained at the first temperature or the second temperature, thereby ensuring the stability of combustion.

[0059] Therefore, when the axial wind inner tube 307 moves relative to the axial wind outer tube 306 to be flush with the front end of the axial wind outer tube 306, the angle at which the axial wind is finally sprayed into the kiln body 100 is parallel to the axial direction. When the axial wind inner tube 307 moves relative to the axial wind outer tube 306 to be 100 mm away from the front end of the axial wind outer tube 306, due to the change in the diameter of the axial wind channel 305 at this location, the axial wind is located in the structure with an inclined angle of the axial wind channel 305, and finally sprayed into the kiln body 100 at a certain angle, changing the outlet angle and outlet speed of the axial wind, and also changing the outlet direction, so that its wrapping effect on the fuel is different, so as to change the mixing time and efficiency of the fuel and oxygen, change the shape and size of the flame, and finally change the temperature of the combustion products to be at the first temperature or the second temperature.

[0060] At the same time, when the working conditions in the kiln body 100 affect the temperature of the combustion products, such as when there is too much process air or impurities in the fuel, the fuel temperature may drop sharply. At this time, the position of the axial wind inner pipe 307 can be adjusted to adjust the outlet angle and direction of the axial wind, so that the temperature of the combustion products remains relatively constant to ensure the stability of combustion.

[0061] refer to Figure 2 and Figure 3 , when the channels of the burner include the central air channel 301, the pulverized coal channel 302, the gas channel 303, the swirling air channel 304 and the axial air channel 305, the central air channel 301, the pulverized coal channel 302, the gas channel 303, the swirling air channel 304 and the axial air channel 305 are arranged in sequence along the center of the burner body 300 to the outside direction (for the upper half of the burner body 300, that is, Figure 2 The X2 direction shown in FIG. 1 is, for the lower half of the burner body 300, Figure 2 The axial wind inner tube 307 is used to be arranged in the axial direction (i.e., the axial wind outer tube 306) relative to the axial wind inner tube 307. Figure 2 The rotary wind channel 304 includes a rotary wind inner tube 308, which is used to move axially relative to the axial wind inner tube 307. The gas channel 303 includes a gas inner tube 309, which is used to move axially relative to the rotary wind inner tube 308. The central wind channel 301 includes a central wind inner tube 310, which is used to move axially relative to the gas inner tube 309.

[0062] Among them, the inner wall 311 of the axial wind outer tube and the outer wall 312 of the axial wind inner tube jointly form an axial wind channel 305, the inner wall of the axial wind inner tube 307 and the outer wall 313 of the rotary wind inner tube jointly form a rotary wind channel 304, the inner wall of the rotary wind inner tube 308 and the outer wall of the gas inner tube 309 jointly form a gas channel 303, the inner wall of the gas inner tube 309 and the outer wall 314 of the central wind inner tube jointly form a pulverized coal channel 302, and the inner wall of the central wind inner tube 310 forms a central wind channel 301.

[0063] The same as above is that, with the front end of the axial outer air tube 306 20mm axially backward as the reference line, the length of the axial wind inner tube 307 for axial movement relative to the axial outer air tube 306 is -20mm-100mm. In other words, the axial wind inner tube 307 can be moved to be flush with the front end of the axial wind outer tube 306, that is, -20mm, or it can be moved from a position flush with the front end of the axial wind outer tube 306 to a distance of 120mm from it, that is, 100mm.

[0064] The length of the rotatory wind inner tube 308 for axial movement relative to the axial wind inner tube 307 is 0mm-40mm. In other words, the rotatory wind inner tube 308 can move to be flush with the front end of the axial wind inner tube 307, i.e., 0mm, or can move from the position flush with the front end of the axial wind inner tube 307 to a distance of 40mm therefrom, i.e., 40mm.

[0065] The length of the gas inner tube 309 for axial movement relative to the swirling wind inner tube 308 is 0 mm-40 mm. In other words, the gas inner tube 309 can move to be flush with the front end of the swirling wind inner tube 308, i.e., 0 mm, or can move from the position flush with the front end of the swirling wind inner tube 308 to a distance of 40 mm from the front end, i.e., 40 mm.

[0066] The length of the central air inner tube 310 for axial movement relative to the gas inner tube 309 is -10mm-20mm. In other words, the central air inner tube 310 can move to 10mm forward of the front end of the gas inner tube 309, i.e. -10mm, and can also move from the position -10mm forward of the front end of the axial air inner tube 307 to a distance of 30mm, i.e. 20mm.

[0067] Among them, the inner wall 311 of the axial wind outer tube gradually starts to change its diameter at 100 mm from the front end of the axial wind outer tube 306 along the axial direction, and the diameter changes from large to small, and stops changing its diameter at 140 mm from the front end of the axial wind outer tube 306 along the axial direction, that is, from 100 mm to 140 mm from the front end of the axial wind outer tube 306 along the axial direction, the inner wall 311 of the axial wind outer tube has a gradually shrinking structure, that is, along the axial direction, it has a structure that is wide at the front and narrow at the back, that is, it has a certain slope here. The diameter remains unchanged at 140 mm to 200 mm from the front end of the axial wind outer tube 306 along the axial direction, and gradually starts to change its diameter at 200 mm from the front end of the axial wind outer tube 306 along the axial direction, and the diameter changes from small to large.

[0068] The outer wall 312 of the axial wind inner tube gradually starts to change in diameter at a distance of 20 mm in the axial direction from the front end of the axial wind inner tube 307, and the diameter changes from large to small, and stops changing in diameter at a distance of 80 mm in the axial direction from the front end of the axial wind inner tube 307, that is, from 20 mm to 80 mm in the axial direction from the front end of the axial wind inner tube 307, the outer wall 312 of the axial wind inner tube has a tapered structure, that is, along the axial direction, it has a structure that is wide in the front and narrow in the back, that is, it has a certain slope.

[0069] In other words, the axial wind channel 305 formed by the inner wall 311 of the axial wind outer tube and the outer wall 312 of the axial wind inner tube is a variable diameter channel, that is, when the axial wind enters the first cavity 101 of the kiln body 100 from the axial wind channel 305, due to the influence of the variable diameter of the axial wind channel 305, the amount and speed of the axial wind entering the first cavity are changed, so as to adjust and control the temperature of the combustion products in the first cavity, so that the temperature of the combustion products is converted between the first temperature or the second temperature or maintained at the first temperature or the second temperature, thereby ensuring the stability of combustion.

[0070] Therefore, when the axial wind inner tube 307 moves relative to the axial wind outer tube 306 to be flush with the front end of the axial wind outer tube 306, the angle at which the axial wind is finally sprayed into the kiln body 100 is parallel to the axial direction. When the axial wind inner tube 307 moves relative to the axial wind outer tube 306 to be 100 mm away from the front end of the axial wind outer tube 306, due to the change in the diameter of the axial wind channel 305 at this location, the axial wind is located in the structure with an inclined angle of the axial wind channel 305, and finally sprayed into the kiln body 100 at a certain angle, changing the outlet angle of the axial wind and also changing the outlet direction, so that its wrapping effect on the fuel is different, so as to change the mixing time and efficiency of the fuel and oxygen, change the shape and size of the flame, and finally change the temperature of the combustion products to be at the first temperature or the second temperature.

[0071] At the same time, when the working conditions in the kiln body 100 affect the temperature of the combustion products, such as when there is too much process air or impurities in the fuel, the temperature of the combustion products may drop sharply. At this time, the position of the axial wind inner pipe 307 can be adjusted to adjust the outlet angle and direction of the axial wind, so that the temperature of the combustion products remains relatively constant to ensure the stability of combustion.

[0072] The outer wall 313 of the rotary air inner tube gradually starts to change in diameter from a position flush with the front end of the rotary air inner tube 308, and the diameter changes from large to small, and stops changing in diameter at a position 20 mm axially away from the front end of the rotary air inner tube 308, that is, from being flush with the front end of the rotary air inner tube 308 to 20 mm along the axial direction, the outer wall 313 of the rotary air inner tube has a tapered structure, that is, along the axial direction, it has a structure that is wide in front and narrow in the back, that is, it has a certain slope here.

[0073] In other words, the rotary wind channel 304 formed by the inner wall of the axial wind inner tube 307 and the outer wall 313 of the rotary wind inner tube is a variable diameter channel. That is to say, when the rotary wind enters the first cavity 101 of the kiln body 100 from the rotary wind channel 304, due to the influence of the variable diameter of the rotary wind channel 304, the amount and speed of the rotary wind entering the first cavity are changed, so as to adjust and control the temperature of the combustion products in the first cavity, so that the temperature of the combustion products is converted between the first temperature or the second temperature or maintained at the first temperature or the second temperature, thereby ensuring the stability of combustion.

[0074] Therefore, when the rotary wind inner tube 308 moves relative to the axial wind inner tube 307 to be flush with the front end of the axial wind inner tube 307, the angle at which the rotary wind is finally sprayed into the kiln body 100 is parallel to the axial direction. When the rotary wind inner tube 308 moves relative to the axial wind inner tube 307 to be 20 mm away from the front end of the axial wind inner tube 307, due to the change in the diameter of the rotary wind channel 304 at this location, the axial wind is finally sprayed into the kiln body 100 at a certain angle at the structure with an inclined angle of the rotary wind channel 304, which changes the outlet angle of the rotary wind and also changes the outlet direction, so that its wrapping effect on the fuel is different, so as to change the mixing time and efficiency of the fuel and oxygen, change the shape and size of the flame, and finally change the temperature of the combustion products to make them at the first temperature or the second temperature.

[0075] At the same time, when the working conditions in the kiln body 100 affect the temperature of the combustion products, such as when there is too much process air or impurities in the fuel, the temperature of the combustion products may drop sharply. At this time, the position of the axial wind inner pipe 307 can be adjusted to adjust the outlet angle and direction of the axial wind, so that the temperature of the combustion products remains relatively constant to ensure the stability of combustion.

[0076] At the same time, reference Figure 6 Combined with Figure 2Since the front end (i.e., the head) of the swirl wind inner tube 308 is provided with a swirl part, when the swirl wind passes through the front end of the swirl wind inner tube 308, the angle of its wind direction will change. The swirl part is provided at the front end of the swirl wind inner tube 308, and includes a plurality of swirl pieces 315. The plurality of swirl pieces 315 are arranged along the circumferential direction (i.e., Figure 6 C direction as shown in the figure), each swirl blade 315 has a certain angle with the axial direction to form a groove, and the angle of the groove (i.e. Figure 6 The range of a) shown is 0°-40°, for example 0°, 15°, 30°, 40°, etc.

[0077] Among them, the outer wall 314 of the central wind inner tube gradually starts to change its diameter from the position flush with the front end of the central wind inner tube 310, and the diameter changes from large to small, and stops changing its diameter at a position 20 mm axially away from the front end of the central wind inner tube 310, that is, from being flush with the front end of the central wind inner tube 310 to 20 mm along the axial direction, the outer wall 314 of the central wind inner tube has a tapered structure, that is, along the axial direction, it has a structure that is wide in front and narrow in the back, that is, it has a certain slope here.

[0078] In other words, the gas channel 303 formed by the outer wall 314 of the central air inner tube and the inner wall of the gas inner tube 309 is a variable diameter channel, that is, when the gas enters the first cavity 101 of the kiln body 100 from the gas channel 303, due to the influence of the variable diameter of the gas channel 303, the amount and speed of the gas entering are changed, so as to adjust and control the temperature of the combustion products in the first cavity, so that the temperature of the combustion products is converted between the first temperature or the second temperature or maintained at the first temperature or the second temperature, thereby ensuring the stability of combustion.

[0079] Therefore, when the central air inner tube 310 moves relative to the gas inner tube 309 to 10 mm forward of the front end of the gas inner tube 309, i.e. -10 mm, the angle at which the gas is finally sprayed into the kiln body 100 is parallel to the axial direction. When the central air inner tube 310 moves relative to the gas inner tube 309 to a distance of 30 mm, i.e. 20 mm, from the gas inner tube 309, due to the change in the diameter of the gas channel 303 at this location and the structure of the gas channel 303 with an inclined angle, the gas is finally sprayed into the kiln body 100 at a certain angle, which changes the outlet angle of the gas and also changes the outlet direction, so that its wrapping effect on the fuel is different, so as to change the mixing time and efficiency of the fuel and oxygen, change the shape and size of the flame, and finally change the temperature of the combustion products to be at the first temperature or the second temperature.

[0080] At the same time, when the working conditions in the kiln body 100 affect the temperature of the combustion products, such as when there is too much process air or impurities in the fuel, the temperature of the combustion products may drop sharply. At this time, the position of the axial wind inner pipe 307 can be adjusted to adjust the outlet angle and direction of the axial wind, so that the temperature of the combustion products remains relatively constant to ensure the stability of combustion.

[0081] refer to Figure 4 When the channels of the burner include a central wind channel 301, a pulverized coal channel 302, a rotary wind channel 304 and an axial wind channel 305, the central wind channel 301, the pulverized coal channel 302, the rotary wind channel 304 and the axial wind channel 305 are sequentially spaced apart in an outward direction from the center of the burner body 300, the axial wind channel 305 includes an axial wind inner tube 307 and an axial wind outer tube 306, the axial wind inner tube 307 is used to move axially relative to the axial wind outer tube 306, the rotary wind channel 304 includes a rotary wind inner tube 308, the rotary wind inner tube 308 is used to move axially relative to the axial wind inner tube 307, and the central wind channel 301 includes a central wind inner tube 310, the central wind inner tube 310 is used to move axially relative to the rotary wind inner tube 308.

[0082] Different from the above description, the gas channel 303 is missing here, and the other descriptions are the same as above and will not be repeated here.

[0083] For example, reference Figure 2 and Figure 3 The central air passage 301 includes an igniter passage 316, a central gas gun passage 317 and at least one flame detector passage 318. The igniter passage 316, the central gas gun passage 317 and at least one flame detector passage 318 are arranged along the circumferential direction (i.e. Figure 3 C direction) are arranged at intervals and are located inside the central wind channel 301.

[0084] For example, reference Figure 7 The wind box 400 includes a buckle part 401 and two air supply parts 402. The two air supply parts 402 are arranged on the outer periphery of the buckle part 401 and are arranged at intervals along the circumferential direction, but are not limited thereto. There may also be one air supply part 402, three air supply parts 402 or four air supply parts 402. The air supply part 402 is used to supply air to the kiln head cover 200. The buckle part 401 surrounds the burner body 300. A swirl device 403 is arranged in the wind box 400. The swirl device 403 includes a swirl device 403 arranged along the circumferential direction (i.e. Figure 7 A plurality of swirl fins 404 are arranged at intervals (in the C direction as shown).

[0085] For example, reference Figures 7 to 9The axial seal of the buckle portion 401 of the bellows 400 is composed of a first bolt 405, a first sealing packing 406, a first half flange 407, a second bolt 408 and a second half flange 409. The first sealing packing 406 and two half flanges (i.e., the first half flange 407 and the second half flange 409) are combined into a complete sealing flange through the first bolt 405. In other words, the sealing preload bolts and the two half flanges are combined into a complete axial sealing flange through the first bolt.

[0086] For example, reference Figures 7 to 9 The radial seal of the buckle portion 401 of the bellows 400 is composed of a second half flange 409, a pressure plate 410, a third bolt 411, a gasket 412, a second sealing packing 413, and a third sealing packing 414. The two half flanges are combined into a complete radial sealing flange by the first bolt 405. The pressure plate 410 is used to transmit the radial sealing preload force.

[0087] The inlet flange 415 is used to connect the air duct and the wind box 400. The fixing flange 416 is used to fix the wind box 400. The swirl device 403 can be divided into two structures. For example, the swirl device 403 and the wind box 400 are integrated; or the swirl device 403 and the wind box 400 are designed separately, wherein the swirl angle is 0°-30°, such as 0°, 15°, 20°, 25°, 30°, etc.

[0088] In summary, when the burner body 300 of the present application is located in the first cavity 101, the flame length, width, and temperature therein can be adjusted to meet the requirements of rotary kilns with different calcination temperatures. Compared with the hot blast furnace form, the energy utilization rate is significantly improved and the fuel consumption is reduced. When the burner body 300 is located at the wind box 400 position, it meets the requirements of hot blast furnace roasting. Compared with calcination in the kiln, the material yield is significantly improved and overburning is reduced.

[0089] Although the present invention has been illustrated and described with reference to certain preferred embodiments of the present invention, it should be understood by those skilled in the art that the above is a further detailed description of the present invention in conjunction with specific embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. Those skilled in the art may make various changes in form and details, including making several simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A combustion system, applicable to a rotary kiln, comprising: A kiln body, wherein the kiln body is provided with a first cavity, wherein the first cavity is used to contain fuel and combustion products; A kiln head cover, which is arranged at one end of the kiln body and is provided with a second cavity communicating with the first cavity; Characterized in that the combustion system comprises: a burner body, the burner body being movable toward the first cavity or away from the first cavity so that the burner body is in a first state and a second state; A wind box, the wind box is arranged on a side of the kiln head cover away from the kiln body and surrounds the burner body; the wind box comprises a buckle part and an air supply part, the air supply part is arranged on the outer periphery of the buckle part and is used to supply air to the kiln head cover, and the buckle part surrounds the burner body; In the first state, the burner body passes through the wind box and the second cavity and a portion of the burner body is located in the first cavity, so that the temperature of the combustion products is at a first temperature; In the second state, the burner body passes through the wind box and is located outside the second cavity, and the wind box supplies air into the kiln head hood so that the temperature of the combustion product is at a second temperature, which is lower than the first temperature; The burner body is provided with a plurality of channels, the plurality of channels are arranged at intervals in the radial direction, and one or more of the plurality of channels can move in the axial direction so that the temperature of the combustion product is at the first temperature or the second temperature.

2. The combustion system according to claim 1, characterized in that: In the first state, the length of the portion of the burner body located in the first cavity is 1 m-1.5 m, and in the second state, the distance of the burner body located outside the second cavity is 0 mm-500 mm.

3. The combustion system according to claim 1, characterized in that: Along the direction from the center to the outside of the burner body, the multiple channels include a central wind channel, a gas channel and an axial wind channel in sequence. The axial wind channel includes an axial wind inner tube and an axial wind outer tube. The axial wind inner tube is used to move axially relative to the axial wind outer tube. The gas channel includes an inner gas tube. The inner gas tube is used to move axially relative to the axial wind inner tube.

4. The combustion system according to claim 3, characterized in that: The length of the axial wind inner tube for moving relative to the axial wind outer tube along the axial direction is -20mm-100mm, and the length of the gas inner tube for moving relative to the axial wind inner tube along the axial direction is 0mm-40mm.

5. The combustion system according to claim 1, characterized in that: Along the direction from the center to the outside of the burner body, the multiple channels include a center wind channel, a coal powder channel, a gas channel, a rotational wind channel and an axial wind channel in sequence. The axial wind channel includes an axial wind inner tube and an axial wind outer tube. The axial wind inner tube is used to move axially relative to the axial wind outer tube. The rotational wind channel includes a rotational wind inner tube. The rotational wind inner tube is used to move axially relative to the axial wind inner tube. The gas channel includes a gas inner tube. The gas inner tube is used to move axially relative to the rotational wind inner tube. The center wind channel includes a center wind inner tube. The center wind inner tube is used to move axially relative to the gas inner tube.

6. The combustion system according to claim 5, characterized in that The length of the axial wind inner tube used to move along the axial direction relative to the axial wind outer tube is -20mm-100mm, the length of the rotary wind inner tube used to move along the axial direction relative to the axial wind inner tube is 0mm-40mm, the length of the gas inner tube used to move along the axial direction relative to the rotary wind inner tube is 0mm-40mm, and the length of the central wind inner tube used to move along the axial direction relative to the gas inner tube is -10mm-20mm.

7. The combustion system according to claim 1, characterized in that: Along the direction from the center to the outside of the burner body, the multiple channels include a central wind channel, a coal powder channel, a rotary wind channel and an axial wind channel in sequence. The axial wind channel includes an axial wind inner tube and an axial wind outer tube. The axial wind inner tube is used to move axially relative to the axial wind outer tube. The rotary wind channel includes a rotary wind inner tube. The rotary wind inner tube is used to move axially relative to the axial wind inner tube. The central wind channel includes a central wind inner tube. The central wind inner tube is used to move axially relative to the rotary wind inner tube.

8. The combustion system according to claim 7, characterized in that The length of the axial wind inner tube used to move along the axial direction relative to the axial wind outer tube is -20mm-100mm, the length of the rotary wind inner tube used to move along the axial direction relative to the axial wind inner tube is 0mm-40mm, and the length of the central wind inner tube used to move along the axial direction relative to the rotary wind inner tube is -10mm-20mm.

9. The combustion system according to any one of claims 3 to 8, characterized in that: The central wind channel comprises an igniter channel, a central gas gun channel and at least one flame detector channel, wherein the igniter channel, the central gas gun channel and the at least one flame detector channel are arranged at intervals along the circumferential direction and are located inside the central wind channel.

10. The combustion system according to any one of claims 5 to 8, characterized in that: The head of the rotary wind inner tube is provided with a plurality of grooves, which are arranged at intervals along the circumferential direction, and the angle of each groove is 0°-40°.

11. The combustion system according to claim 1, characterized in that: A swirl device is arranged in the wind box, and the swirl device comprises a plurality of swirl fins arranged at intervals along the circumferential direction.

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