阅读说明：本技术 叶片角度可调式煤粉燃烧器 (Blade angle adjustable pulverized coal burner ) 是由 耿明山 郭豪 郑文学 任乐 芦良 吴启明 于 2021-08-31 设计创作，主要内容包括：本发明为一种叶片角度可调式煤粉燃烧器,包括中心风管、浓淡分离筒、一次风管和二次风管,一次风管的外壁和二次风管的内壁之间构成二次风环空,所述二次风环空靠近二次风管的出口端设有沿周向依次相邻设置多个二次风旋流叶片,各二次风旋流叶片与二次风管的径向截面之间的夹角呈能调整的设置；各二次风旋流叶片能同步摆动改变倾斜角度以改变二次风的旋流方向和喷射横截面积。本发明克服现有技术中存在的问题,其一次风管和二次风管之间设置了能摆动改变倾斜角度的二次风旋流叶片,二次风能够在直流、左旋流、右旋流之间转换和调节,实现高温喷射气体的旋流方向的转换,实现旋流角度的实时在线动态调节,同时实现旋流强度的调节。(The invention relates to a pulverized coal burner with adjustable blade angles, which comprises a central air pipe, a shade separation barrel, a primary air pipe and a secondary air pipe, wherein a secondary air annulus is formed between the outer wall of the primary air pipe and the inner wall of the secondary air pipe; each secondary wind swirling flow blade can synchronously swing to change the inclination angle so as to change the swirling flow direction and the jet cross-sectional area of the secondary wind. The secondary air cyclone blade capable of swinging to change the inclination angle is arranged between the primary air pipe and the secondary air pipe, secondary air can be converted and adjusted among direct current, left cyclone and right cyclone, the conversion of the cyclone direction of high-temperature jet gas is realized, the real-time online dynamic adjustment of the cyclone angle is realized, and the adjustment of the cyclone strength is realized at the same time.)

1. A kind of blade angle adjustable pulverized coal burner, including from inside to outside coaxial and radial interval set up central air hose, shade separation cylinder, primary air hose and secondary air hose, the shade separation cylinder locates at the exit end in the primary air hose, locate at the upstream position of the shade separation cylinder on the inner wall of the primary air hose and have pulverized coal shade separator, there are light phase swirl vanes between outer wall of the shade separation cylinder and inner wall of the primary air hose, there are pulverized coal concentrated pipes on the inner wall of the shade separation cylinder, characterized by that, form the secondary air annulus between outer wall of the primary air hose and inner wall of the secondary air hose, the said secondary air annulus is close to the exit end of the secondary air hose and set up multiple secondary air swirl vanes adjacently sequentially along the circumference, the included angle between radial cross-section of each said secondary air swirl vane and secondary air hose is the setting that can be adjusted; each secondary air swirling blade can synchronously swing to change the inclination angle so as to change the swirling direction and the jet cross-sectional area of secondary air; the coal powder concentration and dilution separation device, the dilute phase cyclone blade and the secondary air cyclone blade are electrically connected with the control part.

2. The pulverized coal burner with adjustable blade angle of claim 1, wherein the outer wall of the secondary air duct is provided with a driving structure, the driving structure is connected with a transmission structure, the driving structure drives each secondary air swirling blade to swing through the transmission structure, and the driving structure is electrically connected with the control part.

3. The pulverized coal burner with adjustable blade angle of claim 2, wherein each of the secondary air swirl blades is disposed in a sector shape, the center of the circle of each of the secondary air swirl blades is located on the central axis of the secondary air duct, the radially outer side of each of the secondary air swirl blades is connected to a first rotating shaft, each of the first rotating shafts is disposed along the radial direction of the secondary air duct, the radially inner side of each of the secondary air swirl blades is connected to a second rotating shaft, each of the second rotating shafts is disposed coaxially with the corresponding first rotating shaft, and each of the second rotating shafts is rotatably connected to the primary air duct; and each first rotating shaft penetrates through the secondary air pipe in a rotating mode and then is connected with the transmission structure, and the driving structure drives each secondary air cyclone blade to swing through the transmission structure and the first rotating shaft.

4. The pulverized coal burner with adjustable blade angle of claim 3, wherein the transmission structure comprises a first transmission shaft and a second transmission shaft which are connected in sequence, the first transmission shaft is connected with the driving structure, one end of the second transmission shaft far away from the first transmission shaft is connected with a driving gear, and one end of the first transmission shaft located outside the secondary air pipe is connected with a blade gear; the secondary air cyclone fan is characterized in that a rack ring is arranged between the driving gear and the blade gear, the rack ring is sleeved on the outer side of the secondary air pipe, a first meshing portion is arranged on one side, close to the driving gear, of the rack ring, a second meshing portion is arranged on one side, close to the blade gear, of the rack ring, the first meshing portion is meshed with the driving gear, each blade gear is meshed with the second meshing portion, and the driving structure drives each secondary air cyclone blade to swing through the first transmission shaft, the second transmission shaft, the driving gear, the first meshing portion, the second meshing portion, the blade gear and the first rotation shaft.

5. The pulverized coal burner with adjustable blade angle of claim 4, wherein the central axis of the driving gear is parallel to the central axis of the secondary air duct, a convex ring portion is disposed at one axial side of the rack ring, the first engaging portion is disposed radially inside the convex ring portion, and the driving gear drives the rack to rotate around the central axis of the secondary air duct through the first engaging portion.

6. The pulverized coal burner with adjustable blade angle as set forth in claim 4, wherein a roller is provided between the rack ring and the outer wall of the secondary air duct.

7. The pulverized coal burner as claimed in claim 4, wherein a driven gear is provided on an outer wall of the secondary duct at a circumferential interval from the driving gear, the driven gear being engaged with the first engaging portion.

8. The pulverized coal burner with adjustable blade angle of claim 4, characterized in that the included angle between each secondary air swirl blade and the radial section of the secondary air duct ranges from-90 ° to 90 °.

9. The pulverized coal burner with adjustable blade angle of claim 4, characterized in that the number of the secondary air swirl blades is 12-36.

10. The pulverized coal burner with adjustable blade angle of claim 3, wherein the outlet end of the rich-lean separation barrel is provided with a first flaring with gradually increasing diameter, the outlet end of the primary air pipe is provided with a second flaring with gradually increasing diameter, and the outlet end of the secondary air pipe is provided with a third flaring with gradually increasing diameter.

11. The blade angle adjustable pulverized coal burner of claim 10, wherein the first flare has a flare angle in the range of 10 ° to 15 ° and the second flare has a flare angle in the range of 25 ° to 30 °.

Technical Field

The invention relates to the technical field of spiral-flow type burners, in particular to a pulverized coal burner with adjustable blade angles, which is suitable for the technical field of boiler burners.

Background

With the development of social economy, environmental problems are more and more emphasized by people. The treatment of air pollution is an important component of environmental treatment, and people increasingly pay more attention to environmental problems and atmospheric environmental protection problems along with the development of industry and the improvement of living standard. With the increasing emphasis on environmental issues, the requirements for emissions will become more stringent.

Nitrogen oxides (NOx) are a major class of atmospheric pollutants and are one of the major contributors to the formation of acid rain, photochemical smog, and PM2.5 pollution. NOx is to N₂O、NO₂、NO、N₂O₅And nitrogen oxides such as PAN.

At present, the industrial source NOx emission in China accounts for more than 70% of the total NOx emission amount, and the technology for controlling the emission of NOx in industrial flue gas mainly comprises a combustion control technology and a post-combustion control technology. The combustion control techniques include low nitrogen combustion techniques, reburning techniques, and flue gas recirculation techniques. Among the post-combustion control technologies, Selective Catalytic Reduction (SCR), selective non-catalytic reduction (SNCR), and SCR-SNCR hybrid technologies are the main technologies. The combustion control technology has the advantages of wide application range, good economic benefit, high denitrification efficiency, simple equipment and the like; although the post-combustion control technology can greatly reduce the NOx emission, the equipment is expensive, the operation cost is high, and the arrangement requirement is high. From the technical and economic aspects, the low NOx combustion technology is always the most widely applied measure for controlling the NOx emission of the coal-fired boiler, and even if the flue gas denitration technology after combustion with huge investment and operation cost has to be used for meeting the emission standard, the low NOx combustion technology is still required to be adopted for reducing the NOx concentration at the inlet of the flue gas purification device, so that the aim of saving the operation cost is fulfilled.

The national statistical bureau carries out primary accounting, wherein the total energy consumption of 2020 years is 49.8 hundred million tons of standard coal, the coal consumption accounts for 56.8 percent of the total energy consumption, and the clean energy consumption of natural gas, hydropower, nuclear energy, wind power and the like accounts for 24.3 percent of the total energy consumption.

The acidic pollution gas discharged from the boiler of the coal-fired power plant mainly comprises SOx, NOx and CO₂And the like. During the combustion of coal, the NOx formation is mainly NO and NO₂. According to the mechanism of formation of NOx, it can be classified into thermal NOx, fuel NOx and rapid NOx. The thermal NOx is generated by oxidizing nitrogen in air in the combustion process when the temperature of a hearth is higher than 1350 ℃, so that the generation amount of fuel gas with low calorific value is very small and can be generally ignored; the fuel type NOx is generated by oxidizing nitrogen compounds in fuel in the combustion process, and accounts for more than 90% of the NOx generation amount in the whole combustion process; the rapid NOx is formed by premixing and burning hydrocarbon in fuel and nitrogen in air at the initial stage of combustion, and the formation time is extremely short, and the formation amount is less than 5%, which can be ignored generally.

Currently, low NO is often used_XThe combustion technology mainly comprises the following steps:

first, the low excess air combustion technique allows the combustion process to be performed as close to the theoretical air amount as possible, and NOx production can be suppressed as the excess oxygen in the flue gas decreases. This is one of the simplest methods of reducing NOx emissions.

Secondly, the air staged combustion technology divides the combustion air into the hearth to establish a first combustion area with poor oxygen, and the fuel generates CO and H under the condition of poor oxygen₂Reducing gas, NO is inhibited_XIs generated in the firstThe two combustion zones are filled with excess air to ensure that the fuel is completely combusted, thereby controlling NO in the whole combustion process_XThe amount of production.

Thirdly, the fuel staged combustion technology is adopted, partial fuel is introduced into the first combustion area, and the rest fuel is introduced into the second combustion area or the third combustion area in sequence, so that the fuel is distributed as uniformly as possible in the whole combustion area, the peak temperature of flame is reduced, and the thermal NO is reduced_XThe amount of production.

Fourthly, the smoke recycling technology extracts partial smoke from the air preheater, directly sends the partial smoke into the hearth or enters the hearth through the burner after being mixed with secondary air, reduces the oxygen concentration of the hearth and reduces the temperature of the hearth, thereby reducing NO_xThe emission of (2) and the effective prevention of slagging, but the circulation rate of flue gas recirculation has a large influence on the stability of combustion and is difficult to regulate.

Fifth, low NO_xThe combustor technology applies the air classification and fuel classification principles to the design of a combustor, and reduces the oxygen concentration and the temperature of an ignition region as much as possible so as to achieve the purpose of controlling the generation amount of NOx, and the specially designed combustor is a low NOx combustor and can generally reduce the emission concentration of NOx by 30-60%.

The burner is an important device of the boiler, and ensures stable ignition of fuel, complete combustion of the fuel and the like. The burner performance therefore plays a crucial role in boiler emissions.

Due to low NO_xThe burner has mature technology, simple application, low investment cost and NO increase of operation cost, and can reduce the NO content_xThe advantages of the technical principles combined together, thus generally used for reducing NO of coal-fired boilers_xThe preferred technology for emissions is also widely used in coal-fired utility boilers. Many documents show low NO_xBurner technology with other NO alone_xCompared with the control technology, the control technology has great advantages in comprehensive consideration of denitration efficiency, investment cost, operation cost, technical maturity and the like.

At present, with domestic NO targeting_xLow NO_xThe application of burners is also becoming more and more widespread, but nowWith low-nitrogen burners on NO_xThe control is far less than that of the reburning of boiler fuel and the three-dimensional air classification or flue gas recirculation, the existing reburning of boiler fuel and the three-dimensional air classification or flue gas recirculation have a plurality of problems in application, and many power plants are expected to have a function of reburning of boiler fuel, three-dimensional air classification or flue gas recirculation, and the system is simple, easy to operate, flexible to adjust and capable of reducing NO_xLow NO emission_xA pulverized coal burner.

The cyclone burner mixes primary air carrying pulverized coal with combustion air (secondary air), and sprays the mixture into a boiler hearth in a cyclone mode to further organize combustion. The cyclone burner is composed of air pipes with nozzles, and mainly comprises a primary air pipe for conveying primary air (namely air flow carrying pulverized coal, also called pulverized coal air flow), a secondary air pipe for conveying secondary air, an ignition device for igniting the primary air and the like. The primary air, the secondary air, and the like rotate when passing through a swirler in the burner, and form a rotating jet when being ejected from a nozzle. The rotary jet flow can form a high-temperature flue gas backflow area, and the size of the high-temperature flue gas backflow area directly influences the ignition and combustion of the pulverized coal.

In order to pursue economic effects in some existing thermal power plants, the used coal is various in types and different in quality, for example, high-volatile coal and low-volatile coal are available. The swirl burner in the prior art has limited adjustment degree aiming at the combustion process of different kinds of coal, and can not adjust a proper combustion process when different kinds of coal are combusted.

In the prior art, there is a swirl vane adjusting device (CN 205299510U) which comprises: the barrel, the inside steel sheet that has of barrel, the steel sheet between have the whirl blade, the whirl blade pass through the hub connection at annular connecting plate, annular connecting plate pass through the axle and be connected with the limiting plate, annular connecting plate and pull rod welding.

The cyclone burner (CN 111442263A) suitable for lignite powder concentration separation comprises a central air pipe, a primary air pipe, a secondary air pipe, secondary air swirl vanes, a Venturi pulverized coal concentration pipe, light-phase cyclone vanes, a concentration separation barrel and a pulverized coal concentration and dilution separation device, wherein the central air pipe, the concentration separation barrel, the primary air pipe and the secondary air pipe are sleeved together from inside to outside, the adjacent two separation barrels are arranged at intervals, and a plurality of light-phase cyclone vanes which are uniformly distributed along the circumferential direction of the primary air pipe are arranged between the concentration separation barrel and the primary air pipe.

The above-described prior art has the following problems:

1. the rotational flow blade adjusting mechanism adopts a pull rod structure, the sleeve is driven by the pull rod to move or rotate, the swinging of a plurality of rotational flow blades is realized, the error is large during assembly, the calibration precision is not enough under the cold condition, and the rotational flow degree is not accurately marked; the temperature is high when the equipment runs, and the connecting rod and the hinge joint are easy to be blocked and even blocked to lose the adjusting function; the adjusting mechanism of the existing rotational flow blade is of a structure such as a pull rod and a rotary sleeve, and cannot be adjusted on line in real time;

2. the adjusting range of the swirl blades is small, the swirl angle can be adjusted only in a small range, the conversion of the swirl direction of the swirl blades cannot be realized, and the conversion of clockwise swirl and anticlockwise swirl cannot be realized; meanwhile, the swing angle of the adjusted blade cannot be accurately detected, the range of the swing angle adjusted by the blade is very small, the combustion requirements of multiple coal types cannot be met, the rotational flow strength and the rotational flow angle cannot be adjusted simultaneously, and the production process requirements under different loads and different coal types cannot be met.

Therefore, the inventor provides the pulverized coal burner with the adjustable blade angle by virtue of experience and practice of related industries for many years so as to overcome the defects in the prior art.

Disclosure of Invention

The invention aims to provide a pulverized coal burner with adjustable blade angle, which overcomes the problems in the prior art, a secondary air cyclone blade capable of swinging to change the inclination angle is arranged between a primary air pipe and a secondary air pipe, secondary air can be converted and adjusted among direct current, left cyclone and right cyclone, the conversion of the cyclone direction of high-temperature jet gas is realized, the real-time online dynamic adjustment of the cyclone angle is realized, and the adjustment of the cyclone strength is realized at the same time.

The invention aims to realize the purpose, and the blade angle-adjustable pulverized coal burner comprises a central air pipe, a shade separation barrel, a primary air pipe and a secondary air pipe which are coaxially arranged from inside to outside and are radially sleeved at intervals, wherein the shade separation barrel is positioned at the outlet end in the primary air pipe; each secondary air swirling blade can synchronously swing to change the inclination angle so as to change the swirling direction and the jet cross-sectional area of secondary air; the coal powder concentration and dilution separation device, the dilute phase cyclone blade and the secondary air cyclone blade are electrically connected with the control part.

In a preferred embodiment of the present invention, a driving structure is disposed on an outer wall of the secondary air duct, the driving structure is connected to a transmission structure, the driving structure drives each secondary air swirl blade to swing through the transmission structure, and the driving structure is electrically connected to the control portion.

In a preferred embodiment of the present invention, each secondary air swirl vane is disposed in a sector shape, a center of the circle of each secondary air swirl vane is located on a central axis of a secondary air duct, a radial outer side of each secondary air swirl vane is connected to a first rotating shaft, each first rotating shaft is disposed along a radial direction of the secondary air duct, a radial inner side of each secondary air swirl vane is connected to a second rotating shaft, each second rotating shaft is disposed coaxially with the corresponding first rotating shaft, and each second rotating shaft is rotatably connected to the primary air duct; and each first rotating shaft penetrates through the secondary air pipe in a rotating mode and then is connected with the transmission structure, and the driving structure drives each secondary air cyclone blade to swing through the transmission structure and the first rotating shaft.

In a preferred embodiment of the present invention, the transmission structure includes a first transmission shaft and a second transmission shaft connected in sequence, the first transmission shaft is connected to the driving structure, one end of the second transmission shaft, which is far away from the first transmission shaft, is connected to a driving gear, and one end of the first transmission shaft, which is located outside the secondary air duct, is connected to a blade gear; the secondary air cyclone fan is characterized in that a rack ring is arranged between the driving gear and the blade gear, the rack ring is sleeved on the outer side of the secondary air pipe, a first meshing portion is arranged on one side, close to the driving gear, of the rack ring, a second meshing portion is arranged on one side, close to the blade gear, of the rack ring, the first meshing portion is meshed with the driving gear, each blade gear is meshed with the second meshing portion, and the driving structure drives each secondary air cyclone blade to swing through the first transmission shaft, the second transmission shaft, the driving gear, the first meshing portion, the second meshing portion, the blade gear and the first rotation shaft.

In a preferred embodiment of the present invention, a central axis of the driving gear is parallel to a central axis of the secondary air duct, a convex ring portion is disposed on one axial side of the rack ring, the first engaging portion is disposed on a radially inner side of the convex ring portion, and the driving gear drives the rack to rotate around the central axis of the secondary air duct through the first engaging portion.

In a preferred embodiment of the present invention, a roller is disposed between the rack ring and the outer wall of the secondary air duct.

In a preferred embodiment of the present invention, a driven gear is disposed on an outer wall of the secondary air duct at a circumferential interval from the driving gear, and the driven gear is engaged with the first engaging portion.

In a preferred embodiment of the present invention, an included angle between each of the secondary air swirl vanes and a radial cross section of the secondary air pipe is in a range of-90 ° to 90 °.

In a preferred embodiment of the present invention, the number of the secondary air swirl vanes is 12 to 36.

In a preferred embodiment of the present invention, the outlet end of the shade separating cylinder is provided with a first flaring having an increasing diameter, the outlet end of the primary air pipe is provided with a second flaring having an increasing diameter, and the outlet end of the secondary air pipe is provided with a third flaring having an increasing diameter.

In a preferred embodiment of the present invention, the flaring angle of the first flaring is in a range of 10 ° to 15 °, and the flaring angle of the second flaring is in a range of 25 ° to 30 °.

From the above, the pulverized coal burner with adjustable blade angle of the invention has the following beneficial effects:

in the pulverized coal burner with the adjustable blade angle, the secondary air swirl blades capable of swinging to change the inclination angle are arranged between the primary air pipe and the secondary air pipe, and the included angle between each secondary air swirl blade and the radial section of the secondary air pipe can be adjusted, so that the swirl direction and the injection cross-sectional area of the secondary air are changed, the secondary air can be converted and adjusted among direct current, left swirl and right swirl, the conversion of the swirl direction of high-temperature injection gas is realized, the real-time online dynamic adjustment of the swirl angle is realized, and the adjustment of the swirl strength is realized at the same time;

the swing angle of the secondary air swirl vane can be adjusted randomly within the circumferential range of 360 degrees, and the angle of the secondary air swirl vane can be adjusted within a large range;

the synchronous adjustment of the plurality of secondary air swirling vanes is realized by utilizing a transmission mode that a rack ring is meshed with a plurality of vane gears in the transmission structure;

according to the invention, the regulation mode of the secondary air swirl blade is changed from manual regulation to automatic regulation through the control part and the driving structure, so that the remote real-time online regulation is realized;

the universal coupling is arranged in the transmission structure, so that the problem that the equipment cannot be adjusted due to local deformation of gears, racks and the like or poor production precision, installation coaxiality and the like in the operation process is solved.

Drawings

The drawings are only for purposes of illustrating and explaining the present invention and are not to be construed as limiting the scope of the present invention. Wherein:

FIG. 1: is a sectional view of the pulverized coal burner with adjustable blade angle of the present invention.

FIG. 2: the top view of the secondary air cyclone blade is coincident with the radial section of the secondary air pipe.

FIG. 3: is a view along a direction in fig. 2.

FIG. 4: the secondary air cyclone blade is a top view when being vertical to the radial section of the secondary air pipe.

FIG. 5: is a view along the direction B in figure 4.

FIG. 6: the top view of the secondary air swirl vane of the invention when rotating clockwise relative to the radial section of the secondary air pipe is shown.

FIG. 7: the top view of the secondary air swirl vane of the invention when rotating anticlockwise relative to the radial section of the secondary air pipe is shown.

FIG. 8: is an enlarged view at I in FIG. 1.

In the figure:

100. a pulverized coal burner with adjustable blade angle;

1. a central air duct; 11. a central tube inlet;

2. a thick-thin separation cylinder; 21. a first flare;

3. a primary air duct; 31. a coal powder concentration and dilution separation device; 32. a second flare; 33. an inlet of a primary air duct;

4. a secondary air duct; 41. a third flaring; 42. an inlet of a secondary air duct;

5. a dilute phase swirl vane;

6. a pulverized coal concentrator tube;

7. a secondary air swirl vane; 71. a first rotating shaft; 72. a second rotation shaft;

8. a drive structure; 81. a drive motor; 82. a speed reducer;

9. a transmission structure; 91. a first drive shaft; 92. a second drive shaft; 93. a driving gear; 94. a blade gear; 95. a rack ring; 951. a first engaging portion; 952. a second engaging portion; 953. a convex ring part; 96. a roller; 97. a driven gear; 98. a universal coupling is provided.

Detailed Description

In order to more clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will now be described with reference to the accompanying drawings.

The specific embodiments of the present invention described herein are for the purpose of illustration only and are not to be construed as limiting the invention in any way. Any possible variations based on the present invention may be conceived by the skilled person in the light of the teachings of the present invention, and these should be considered to fall within the scope of the present invention. It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "mounted," "connected," and "connected" are to be construed broadly and may include, for example, mechanical or electrical connections, communications between two elements, direct connections, indirect connections through intermediaries, and the like. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

As shown in fig. 1 to 8, the present invention provides a pulverized coal burner 100 with adjustable blade angle, which comprises a central air duct 1 and a rich-lean separation tube 2 coaxially and radially sleeved from the inside to the outside at intervals, the device comprises a primary air pipe 3 and a secondary air pipe 4, wherein a shade separation barrel 2 is positioned at the outlet end in the primary air pipe, a pulverized coal shade separation device 31 is arranged at the upstream position of the shade separation barrel 2 on the inner wall of the primary air pipe 3, a light-phase cyclone blade 5 is arranged between the outer wall of the shade separation barrel 2 and the inner wall of the primary air pipe 3, a pulverized coal concentration pipe 6 is arranged on the inner wall of the shade separation barrel 2, a secondary air annular space is formed between the outer wall of the primary air pipe 3 and the inner wall of the secondary air pipe 4, a plurality of secondary air cyclone blades 7 are sequentially and adjacently arranged in the circumferential direction near the outlet end of the secondary air pipe, and the included angle between each secondary air cyclone blade 7 and the radial section of the secondary air pipe 4 can be adjusted; each secondary wind swirl vane 7 can synchronously swing to change the inclination angle so as to change the swirl direction and the jet cross-sectional area of the secondary wind; the coal powder concentration and dilution separation device 31, the dilute phase swirl vane 5 and the secondary air swirl vane 7 are electrically connected with the control part.

The pulverized coal wind enters the primary air pipe 3, when passing through the pulverized coal concentration and dilution separation device 31 in the primary air pipe 3, under the action of inertia force, the pulverized coal carried by the primary air is separated in concentration and dilution, namely, the concentration of the pulverized coal is distributed into inner concentration and outer dilution along the radial direction of the primary air pipe 3, the pulverized coal wind close to the central air pipe 1 is called dense-phase primary air, the pulverized coal wind close to the inner wall of the primary air pipe 3 is called light-phase primary air, the pulverized coal wind enters the concentration and dilution separation cylinder 2 and then separates the inner concentration and the outer concentration of the pulverized coal wind from the light concentration, the pulverized coal concentration pipe 6 is arranged on the inner wall of the concentration and dilution separation cylinder 2, secondary concentration of the primary air dense-phase airflow is realized, and the concentration of the pulverized coal on the inner side of the dense-phase primary air duct is higher.

In the blade angle adjustable pulverized coal burner, the secondary air swirl blades capable of swinging to change the inclination angle are arranged between the primary air pipe and the secondary air pipe, the included angle between each secondary air swirl blade and the radial section of the secondary air pipe (namely the inclination angle of each secondary air swirl blade) can be adjusted, so that the swirl direction and the jet cross-sectional area of the secondary air are changed, the secondary air can be converted and adjusted among direct current, left swirl and right swirl, the conversion of the swirl direction of high-temperature jet gas is realized, the real-time online dynamic adjustment of the swirl angle is realized, and the adjustment of the swirl strength is realized at the same time.

Further, as shown in fig. 1, a driving structure 8 is disposed on an outer wall of the secondary air duct 4, a transmission structure 9 is connected to the driving structure 8, the driving structure 8 drives each secondary air swirl blade 7 to swing through the transmission structure 9, and the driving structure 8 is electrically connected to the control portion.

Further, as shown in fig. 1 and 3, each secondary air swirl vane 7 is disposed in a fan shape (when the secondary air swirl vane 7 rotates to the radial section of the secondary air duct 4, the side edges of both sides in the circumferential direction are disposed along the radial direction of the secondary air duct 4, and the side edges of both sides in the radial direction are arc-shaped respectively), the center of the circle of each secondary air swirl vane 7 is located on the central axis of the secondary air duct 4, the radial outer side of each secondary air swirl vane 7 is connected with a first rotating shaft 71 respectively, each first rotating shaft 71 is disposed along the radial direction of the secondary air duct 4, the radial inner side of each secondary air swirl vane 7 is connected with a second rotating shaft 72 respectively, each second rotating shaft 72 is disposed coaxially with the corresponding first rotating shaft 71, and each second rotating shaft 72 is rotatably connected to the primary air duct 3; each first rotating shaft 71 is connected with the transmission structure 9 after penetrating through the secondary air pipe 4 in a rotating way, and the driving structure 8 drives each secondary air cyclone blade to swing through the transmission structure 9 and the first rotating shaft 71.

As shown in fig. 2, 3, 4, 5, 6, and 7, in the present embodiment, the included angle between each of the secondary air swirling vanes 7 and the radial cross section of the secondary air duct 4 is in the range of-90 ° to 90 °. That is, the swing angle α of each secondary air swirl vane 7 with respect to the radial cross section of the secondary air duct 4 (the plane perpendicular to the central axis of the secondary air duct 4) is in the range of-90 ° to 90 ° (in the present invention, this angle is negative when the secondary air swirl vane 7 rotates counterclockwise, and positive when it rotates clockwise), and the secondary air swirl vanes 7 rotate to open the secondary air annulus fully or circulate swirl or are blocked by the maximum area. The swing angle of the secondary air swirl vanes 7 can be adjusted randomly within a 360-degree circumferential range, and the swing angle range can be determined according to actual requirements.

As shown in fig. 2 and 3, when the secondary air swirl vanes 7 are located on the radial section of the secondary air pipe 4, the secondary air swirl vanes 7 rotate to the parallel and level state, the working surfaces of the secondary air swirl vanes 7 are parallel and level with each other to form an annular surface (annular plate structure), the secondary air swirl vanes 7 have no swirl effect on high-temperature flue gas, most of the secondary air annulus is blocked by the secondary air swirl vanes 7, the air flow is very small, small-flow injection can be realized, and the low-load combustion requirement of the combustor is met.

As shown in fig. 4 and 5, when the secondary air swirl vanes 7 are perpendicular to the radial cross section of the secondary duct 4 (the secondary air swirl vanes 7 are parallel to the central axis of the secondary duct 4), the secondary air annulus is fully open, and the secondary air is injected in a direct manner, so that no swirl effect is produced.

Further, the number of the secondary air swirl vanes 7 is preferably even, and the secondary air swirl vanes are uniformly arranged in the circumferential direction, in the embodiment, the number of the secondary air swirl vanes 7 is 12-36, and the specific number can be determined according to the diameter of the combustor.

Further, as shown in fig. 1 and 8, the transmission structure 9 includes a first transmission shaft 91 and a second transmission shaft 92 connected in sequence, and the first transmission shaft 91 and the second transmission shaft 92 are connected by a universal joint 98; a plurality of fixed support structures are arranged on the outer wall of the secondary air pipe 4, and the first transmission shaft 91 and the second transmission shaft 92 can rotate and can be slidably arranged through the fixed support structures; the universal coupling 98 is arranged in the transmission structure 9, so that the problem that the equipment cannot be adjusted due to the local deformation of gears, racks and the like or the poor production precision, installation coaxiality and the like in the operation process is solved;

the first transmission shaft 91 is connected with the driving structure 8, one end of the second transmission shaft 92, which is far away from the first transmission shaft 91, is connected with a driving gear 93, and one end of the first rotation shaft 71, which is positioned outside the secondary air duct 4, is connected with a blade gear 94; set up rack ring 95 between driving gear 93 and the blade gear 94, the outside of secondary tuber pipe 4 is located to rack ring 95 cover, one side that rack ring 95 is close to driving gear 93 sets up first meshing portion 951, one side that rack ring 95 is close to blade gear 94 sets up second meshing portion 952, first meshing portion 951 and driving gear 93 mesh, each blade gear 94 all meshes with second meshing portion 952, drive structure 8 is through first transmission shaft 91, second transmission shaft 92, driving gear 93, first meshing portion 951, second meshing portion 952, blade gear 94 and the swing of each secondary wind whirl blade 7 of first rotation axis 71 drive.

Further, as shown in fig. 1 and 8, a central axis of the pinion 93 is parallel to a central axis of the secondary air duct 4, a convex ring portion 953 is provided at one axial side of the rack ring 95, a first engaging portion 951 is provided at a radially inner side of the convex ring portion 953, and the pinion 93 drives the rack ring 95 to rotate around the central axis of the secondary air duct 4 through the first engaging portion 951.

A second engaging portion 952 is provided on the other axial side surface of the rack ring 95, the central axis of the vane gear 94 (the first rotary shaft 71) is perpendicular to the central axis of the secondary air duct 4, and the rack ring 95 drives the vane gear 94 to rotate around the first rotary shaft 71 (the radial direction of the secondary air duct 4) via the second engaging portion 952.

The racks of the first engaging portion 951 and the second engaging portion 952 on the rack ring 95 may be directly processed on the rack ring 95, or may be independently processed, and the processed racks are fixed to the rack ring, thereby facilitating maintenance and replacement.

Synchronous adjustment of the plurality of secondary air swirl vanes 7 is realized by a transmission mode of meshing the rack ring 95 with the plurality of vane gears 94.

Further, as shown in fig. 8, rollers 96 are provided between the rack ring 95 and the outer wall of the secondary air duct 4. There is certain radial clearance between rack ring and the secondary tuber pipe outer wall, sets up gyro wheel 96 in the clearance, and gyro wheel 96 can support rack ring 95, also can reduce the friction of rack ring 95 and secondary tuber pipe 4, realizes the smooth and easy rotation of rack ring 95. The number of the rollers 96 is at least 3, preferably 6 to 12.

Further, as shown in fig. 1, a driven gear 97 is provided on an outer wall of the secondary duct 4 at a circumferential interval from the driving gear 93, and the driven gear 97 is engaged with the first engaging portion 951.

The outer wall of secondary tuber pipe 4 sets up two at least driven gear 97, and driven gear 97 passes through first meshing portion 951 meshing with rack ring 95, and the driving gear 93 avoids rack ring 95's eccentric rotation with driven gear 97 common and rack ring 95 meshing transmission. The driving gears 93 and the driven gears 97 are uniformly arranged on the outer wall of the secondary air duct 4 along the circumferential direction, and are located on the circumference of a certain imaginary circle with the center of the circle at the central axis of the secondary air duct 4.

Further, as shown in fig. 1, the driving structure 8 includes a driving motor 81, and the driving motor 81 is connected to the first transmission shaft 91 through a speed reducer 82. The control section adjusts the rotation direction and the number of rotation turns of the driving motor 81, and finally controls the adjustment of the swing angle of the secondary air swirl vane 7. According to the invention, the adjustment mode of the secondary air swirl vanes 7 is changed from manual adjustment to automatic adjustment through the control part and the driving structure, so that the remote real-time online adjustment is realized.

Further, as shown in fig. 1, the outlet end of the shade separating cylinder 2 is provided with a first flaring 21 with gradually increasing diameter, the outlet end of the primary air pipe 3 is provided with a second flaring 32 with gradually increasing diameter, and the outlet end of the secondary air pipe 4 is provided with a third flaring 41 with gradually increasing diameter.

Furthermore, the flaring angle beta of the first flaring 21 is in the range of 10-15 degrees, the flow guiding effect on the primary air light phase can be achieved, and the mixing time of the primary air dense phase and the primary air light phase in the hearth is delayed;

the flaring angle gamma of the second flaring 32 is 25-30 degrees, which plays a role in guiding secondary air and prolongs the mixing time of the secondary air and the primary air in the hearth.

Further, as shown in fig. 1, a central pipe inlet 11 is arranged at an inlet end of the central air pipe 1, a primary air pipe inlet 33 is arranged at an inlet end of the primary air pipe 3, a secondary air pipe inlet 42 is arranged at an inlet end of the secondary air pipe 4, the central pipe inlet 11, the primary air pipe inlet 33 and the secondary air pipe inlet 42 are all connected with a pipeline through flanges, and a flow meter and a regulating valve are arranged on the pipeline.

The working principle of the blade angle adjustable pulverized coal burner 100 of the present invention is as follows:

according to the requirement of the combustion load of the combustor, the air quantities in the central air pipe 1, the primary air pipe 3 and the secondary air pipe 4 are adjusted, according to the shape and the condition of flame combustion on the outlet side of the combustor, the rotating direction and the number of rotating turns of the driving motor 81 are adjusted by a control part (a PLC), the speed reducer is used for driving the transmission structure 9 (a first transmission shaft 91 and a second transmission shaft 92) to rotate, the first transmission shaft 91 and the second transmission shaft 92 drive the driving gear 93 to rotate, the driving gear 93 rotates to drive the rack ring 95 to rotate around the central shaft of the secondary air pipe 4, the rack ring 95 drives the blade gear 94 to rotate through the second meshing part 952, the blade gear 94 drives the secondary air cyclone blades 7 to rotate through the first rotating shaft 71, the change of the included angle of the radial section of the secondary air cyclone blades 7 and the secondary air pipe 4 is realized, the dynamic adjustment of the cyclone angle is realized, and the adjustment of the cyclone strength is realized at the same time. The included angle between the secondary air swirl blades 7 and the radial section of the secondary air pipe 4 is adjusted by using the driving motor, so that the outlet air of the secondary air can be converted and adjusted among direct current, left swirl and right swirl.

From the above, the pulverized coal burner with adjustable blade angle of the invention has the following beneficial effects:

in the pulverized coal burner with the adjustable blade angle, the secondary air swirl blades capable of swinging to change the inclination angle are arranged between the primary air pipe and the secondary air pipe, and the included angle between each secondary air swirl blade and the radial section of the secondary air pipe can be adjusted, so that the swirl direction and the injection cross-sectional area of the secondary air are changed, the secondary air can be converted and adjusted among direct current, left swirl and right swirl, the conversion of the swirl direction of high-temperature injection gas is realized, the real-time online dynamic adjustment of the swirl angle is realized, and the adjustment of the swirl strength is realized at the same time;

the swing angle of the secondary air swirl vane can be adjusted randomly within the circumferential range of 360 degrees, and the angle of the secondary air swirl vane can be adjusted within a large range;

the synchronous adjustment of the plurality of secondary air swirling vanes is realized by utilizing a transmission mode that a rack ring is meshed with a plurality of vane gears in the transmission structure;

according to the invention, the regulation mode of the secondary air swirl blade is changed from manual regulation to automatic regulation through the control part and the driving structure, so that the remote real-time online regulation is realized;

the universal coupling is arranged in the transmission structure, so that the problem that the equipment cannot be adjusted due to local deformation of gears, racks and the like or poor production precision, installation coaxiality and the like in the operation process is solved.

The above description is only an exemplary embodiment of the present invention, and is not intended to limit the scope of the present invention. Any equivalent changes and modifications that can be made by one skilled in the art without departing from the spirit and principles of the invention should fall within the protection scope of the invention.