阅读说明：本技术 一种适用于褐煤的煤粉浓淡分离的旋流燃烧器 (Cyclone burner suitable for pulverized coal concentration separation of lignite ) 是由 韩升利 王通 黄莺 王静杰 徐彦辉 祝令昆 于 2020-04-16 设计创作，主要内容包括：一种适用于褐煤的煤粉浓淡分离的旋流燃烧器,属于锅炉燃烧器技术领域,以解决现有的燃用褐煤的旋流燃烧器一次风风煤比与一次风率较大,二次风率较小,造成一次风与二次风的动量比与燃用烟煤相比产生较大差别,影响燃烧器的流场与燃烧过程控制,使燃烧器燃烧过程不易控制,火焰回流区稳定性差,产生较高的NO<Sub>x</Sub>污染物的问题。本发明包括中心风管、一次风管、二次风管、二次风旋流叶片、文丘里煤粉浓缩管、淡相旋流叶片、浓淡分离隔筒和煤粉浓淡分离装置,中心风管、浓淡分离隔筒、一次风管和二次风管由内向外套设在一起,且相邻两者之间间隔设置,浓淡分离隔筒和一次风管之间设置有多个沿一次风管圆周方向均匀分布的淡相旋流叶片。(The utility model provides a pulverized coal shade separation's cyclone burner suitable for brown coal, belongs to boiler burner technical field to solve current cyclone burner that fires brown coal, the wind-coal ratio of the wind of one time is great with primary air rate, the overgrate air rate is less, cause the momentum ratio of primary air and overgrate air to compare with burning bituminous coal and produce great difference, influence the flow field and the combustion process control of combustor, make the combustor combustion process be difficult to control, flame backward flow district stability is poor, produce higher NO x The problem of contamination. The invention comprises a central air pipe, a primary air pipe, a secondary air swirl vane, a Venturi pulverized coal concentration pipe, a light phase swirl vane, a shade separation barrel and a pulverized coal shade separation device, wherein the central air pipe, the shade separation barrel, the primary air pipe and the secondary air pipe are sleeved together from inside to outside, and are arranged at intervals between the two adjacent air pipes, a plurality of air pipes are arranged between the shade separation barrel and the primary air pipe along the circumferential direction of the primary air pipeEvenly distributed light phase rotational flow blades.)

1. The utility model provides a cyclone burner suitable for rich-lean separation of buggy of brown coal, includes central tuber pipe (1), air hose (2), secondary air pipe (3), overgrate air whirl blade (12) and venturi pulverized coal concentrator (6), its characterized in that: it also comprises a dilute phase cyclone blade (4), a thick-thin separation barrel (5) and a coal powder thick-thin separation device (13), wherein the central air pipe (1), the thick-thin separation barrel (5), the primary air pipe (2) and the secondary air pipe (3) are sleeved together from inside to outside, and the two are arranged at intervals, a plurality of light phase cyclone blades (4) which are uniformly distributed along the circumferential direction of the primary air pipe (2) are arranged between the thick and thin separation barrel (5) and the primary air pipe (2), a plurality of secondary air cyclone blades (12) which are uniformly distributed along the circumferential direction of the primary air pipe (2) are arranged between the primary air pipe (2) and the secondary air pipe (3), a coal powder thick and thin separation device (13) is arranged on the inner wall of the primary air pipe (2), a Venturi coal powder concentration pipe (6) is arranged on the inner wall of the thick and thin separation barrel (5), and the concentration separation barrel (5) is arranged at the primary air downstream of the pulverized coal concentration separation device (13) on the primary air pipe (2).

2. The cyclone burner for the separation of pulverized coal from lignite according to claim 1, wherein: the air outlet of each of the thick-thin separating cylinder (5), the primary air pipe (2) and the secondary air pipe (3) is provided with a flaring.

3. The cyclone burner for the concentration separation of pulverized coal applicable to lignite according to claim 2, wherein a flare angle (α) of the concentration separation barrel (5) is 10-15 °.

4. The cyclone burner for the concentration separation of pulverized coal applicable to lignite according to claim 2, wherein the flaring angle (β) of the primary air pipe (2) is 25-30 °.

5. The cyclone burner for the separation of pulverized coal of lignite according to any one of claims 1 to 4, wherein: a plurality of stable combustion teeth (1-1) which are uniformly distributed along the circumferential direction are arranged at the air outlet of the central air pipe (1).

6. The cyclone burner for the separation of pulverized coal from lignite according to claim 1, wherein: and the secondary air pipe (3) is provided with an air adjusting door (7).

7. The cyclone burner for the separation of pulverized coal from lignite according to claim 1, wherein: the secondary air box comprises a secondary air box panel (8) and a blade adjusting mechanism (9), wherein the blade adjusting mechanism (9) comprises a sleeve (9-1), a guide sleeve (9-2), an adjusting rod (9-3), a handle (9-4), rollers (9-5), a first connecting rod (9-6), a second connecting rod (9-7) and rotating shafts (9-8), each secondary air swirling blade (12) is rotatably arranged on the side wall of the secondary air pipe (3) through one rotating shaft (9-8), each rotating shaft (9-8) is fixedly connected with the first connecting rod (9-6), two ends of the second connecting rod (9-7) are respectively hinged with the first connecting rod (9-6) and the sleeve (9-1), the sleeve (9-1) is sleeved on the secondary air pipe (3), and the sleeve (9-1) is rotatably provided with four rollers along the inner wall of the circumferential direction, the four rollers are in contact with the outer surface of the secondary air pipe (3), the adjusting rod (9-3) is fixedly connected with the sleeve (9-1), the guide sleeve (9-2) is fixedly connected on the secondary air box panel (8), the adjusting rod (9-3) is arranged in the guide sleeve (9-2) in a sliding mode, and the end portion of the adjusting rod (9-3) is fixedly provided with the handle (9-4).

8. The cyclone burner for the separation of pulverized coal from lignite according to claim 1, wherein: the coal powder concentration and dilution separation device (13) comprises two groups of check blocks (13-1), wherein the two groups of check blocks (13-1) are respectively and uniformly fixedly connected to the inner wall of the primary air pipe (2) along the circumferential direction of the primary air pipe (2), the two groups of check blocks (13-1) are arranged in a certain interval in a staggered mode, and the certain interval is formed between each group of check blocks (13-1) and the outer wall of the central air pipe (1).

9. The cyclone burner for the separation of pulverized coal from lignite according to claim 8, wherein: the longitudinal section of each block (13-1) in the two groups of blocks (13-1) is isosceles trapezoid, and the cross section of each block (13-1) in the two groups of blocks (13-1) is fan-shaped.

10. The cyclone burner for the separation of pulverized coal from lignite according to claim 9, wherein: the included angle (gamma) between the windward side (H) of each block (13-1) in the two groups of blocks (13-1) and the side wall of the primary air pipe (2) is 25-35 degrees.

Technical Field

The invention relates to a boiler burner, in particular to a cyclone burner for lignite, and belongs to the technical field of boiler burners.

Background

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.

Due to the fact that the types of fire coal are various, the physical and chemical properties of various coal qualities are greatly different, and the structure of the combustor needs to be designed in a targeted mode according to the coal quality difference.

At present, most of cyclone burners are developed on the basis of bituminous coal, are mainly suitable for bituminous coal, and are provided with internal secondary air. Compared with a bituminous coal burner, the lignite burner has the advantages that the primary air-coal ratio is higher than the primary air ratio, the burnout air is separated from the total secondary air, the secondary air ratio entering the burner is smaller, the momentum ratio (the ratio of direct current air to rotational flow air) of the primary air to the secondary air of the lignite burner is larger, the flow field and the combustion process of the lignite burner are affected, the stability of a flame backflow area is poor, and higher NO is generated_xA contaminant.

Disclosure of Invention

The invention aims to solve the problems that the existing cyclone burner has larger primary air-coal ratio and primary air rate and smaller secondary air rate, so that the momentum ratio of primary air and secondary air generates larger difference, the flow field and the combustion process of the burner are influenced and are difficult to control, and a flame backflow area has poor stability to generate higher NO_xThe problem of pollutants, and provides a cyclone burner suitable for the coal dust concentration separation of lignite.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a cyclone burner suitable for the concentration and dilution separation of pulverized coal of lignite comprises a central air pipe, a primary air pipe, a secondary air cyclone blade, a Venturi pulverized coal concentration pipe, a dilute phase cyclone blade, a concentration and dilution separation barrel and a pulverized coal concentration and dilution separation device, wherein the central air pipe, the concentration and dilution separation barrel, the primary air pipe and the secondary air pipe are sleeved together from inside to outside, and the two are arranged at intervals, a plurality of light phase cyclone blades which are uniformly distributed along the circumferential direction of the primary air pipe are arranged between the concentration and dilution separation barrel and the primary air pipe, a plurality of secondary air cyclone blades which are uniformly distributed along the circumferential direction of the primary air pipe are arranged between the primary air pipe and the secondary air pipe, a coal powder concentration and dilution separation device is arranged on the inner wall of the primary air pipe, a Venturi coal powder concentration pipe is arranged on the inner wall of the concentration and dilution separation barrel, and the concentration separation barrel is arranged at the primary air downstream of the pulverized coal concentration separation device on the primary air pipe.

Compared with the prior art, the invention has the following beneficial effects:

firstly, the invention cancels the inner secondary air with lower flow velocity (usually, the swirl burner is provided with the inner secondary air), therefore, all the secondary air of the invention can obtain higher secondary air velocity, and the momentum of the swirl air is improved.

And secondly, the primary air is divided into a thick phase and a thin phase, the thin phase primary air is weak rotational flow (generally, the whole primary air of the rotational flow combustor is direct current air), the thin phase primary air and the secondary air provide the rotational momentum of the combustor, the thick phase primary air is direct current air, and the rotational flow design of the thin phase primary air increases the air volume and momentum of the rotational flow air and reduces the air volume and momentum of the direct current primary air, the momentum proportion of the rotational flow air and the direct current air is more reasonable, a larger central backflow area is obtained, the flow field of the combustor is more stable, the combustion is fast ignited, the burnout rate of pulverized coal is high, and the unburned heat loss is smaller.

Thirdly, as shown in fig. 8, due to the swirling action of the burner, a stable central backflow area is formed outside the nozzle of the burner, the backflow area reflows the burnt high-temperature flue gas to the root of the primary air, the pulverized coal in the concentrated-phase primary air enters the backflow area due to the inertia effect, an environment (a P area in the figure) with high pulverized coal concentration and high temperature is formed at the edge of the backflow area, and the high reactivity of the lignite ensures the volatile component release of the pulverized coal in the fuel-rich area. The coal powder is rapidly heated by the high-temperature flue gas to reach an ignition point and ignited, and light-phase coal powder is ignited from inside to outside, so that oxygen contained in primary air is rapidly consumed, a reducing product (a Q area in the figure) is generated, NOx generated at the early stage is reduced in a reducing atmosphere, and the low level (a W area in the figure) of a flue gas pollutant NOx is ensured. The gradual mixing process of the secondary air is controlled, and the residual coke is burnt out under a high-temperature environment (an R area in the figure).

Drawings

FIG. 1 is a schematic view of the present invention;

FIG. 2 is an enlarged view of a portion of FIG. 1 at I;

fig. 3 is a plan view of the blade adjusting mechanism 9;

FIG. 4 is a view from the direction A of FIG. 1;

FIG. 5 is a cross-sectional view B-B of FIG. 1;

FIG. 6 is a cross-sectional view C-C of FIG. 1;

FIG. 7 is a schematic longitudinal sectional view of a stopper 13-1 of the pulverized coal concentration and dilution separation device 13;

FIG. 8 is a graph of the combustion effect at the nozzle of the present invention, with the arrows indicating the direction of combustion flow.

Detailed Description

The invention will be described in further detail below with reference to the accompanying drawings: the present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation is given, but the scope of the present invention is not limited to the following embodiments.