阅读说明：本技术 一种多段式降低锅炉NOx的方法及设备 (Method and equipment for reducing NOx of boiler in multi-stage mode ) 是由 侯生存 于 2021-07-22 设计创作，主要内容包括：本发明公开了一种多段式降低锅炉NOx的方法及设备,本发明的有益效果是,通过中转控制结构将煤炭进行分流燃烧,分主燃烧区以及补偿燃烧区,在主燃烧区将锅炉的过量空气系数降到0.75-0.9的范围,主燃烧区的缺氧和低温抑制了NOx的生成,补偿燃烧区通过补入过量空气使炉内的煤粉充分燃烧,一般燃尽分量占锅炉总风量的20％-30％,本方案可以大大增加锅炉的燃尽风量,将锅炉的燃尽风量从18％增加到25％以上而降低NOx。(The invention discloses a method and equipment for reducing boiler NOx in a multi-stage mode, and the method and equipment have the advantages that coal is subjected to flow-division combustion through a transfer control structure, the coal is divided into a main combustion area and a compensation combustion area, the excess air coefficient of a boiler is reduced to the range of 0.75-0.9 in the main combustion area, the generation of NOx is inhibited by the oxygen deficiency and the low temperature of the main combustion area, pulverized coal in the boiler is fully combusted in the compensation combustion area through supplementing excess air, the general burnout component accounts for 20% -30% of the total air quantity of the boiler, the burnout air quantity of the boiler can be greatly increased, and the burnout air quantity of the boiler is increased from 18% to more than 25% so as to reduce NOx.)

1. An apparatus for multi-stage boiler NOx reduction, comprising: the multi-section type flow dividing boiler is characterized in that the transfer box is mounted on the multi-section type flow dividing boiler, a transportation combustion structure and a screening structure are mounted in the multi-section type flow dividing boiler, a transfer control structure is mounted on the transfer box, and the transfer control structure is connected to the transportation combustion structure;

the transfer control structure comprises: the device comprises a combustion concave splitter plate, a transfer splitter plate, a pair of horn-shaped collection inner boxes, a high-temperature coiled pipe, a low-temperature coiled pipe, a circulating air pump, an air flow adjusting assembly and a combustion auxiliary assembly;

the utility model discloses a multistage formula flow distribution boiler, including the concave flow distribution plate of burning, the concave flow distribution plate of burning install in the inboard of multistage formula flow distribution boiler, the transfer flow distribution plate install in the inboard of transfer case, it is a pair of loudspeaker type is collected the inner box and is inserted respectively in the inboard of multistage formula flow distribution boiler, and a pair of loudspeaker type is collected the inner box and is located respectively on the both sides of the concave flow distribution plate of burning, high temperature coiled tube and low temperature coiled tube install in the inboard of transfer case, just high temperature coiled tube and low temperature coiled tube connect respectively in a pair on the loudspeaker type is collected the inner box, the circulating air pump install in on the transfer flow distribution plate, just the circulating air pump connect in on high temperature coiled tube and the low temperature coiled tube.

2. The apparatus for multi-stage boiler NOx reduction according to claim 1, wherein the transport combustion structure comprises: the device comprises a concave transportation block, a plurality of transportation rollers, a plurality of transportation chain wheels, a transportation chain, a transportation driving machine, a concave protective sleeve box, a transportation metal belt and a combustion assembly;

a plurality of the transportation cylinder pass through the bearing cartridge in on the concave type transportation piece, the transportation driving machine install in on the concave type transportation piece, a plurality of the transportation sprocket is installed in a plurality of respectively the transportation cylinder and on the drive end of transportation driving machine, the transportation chain suit in a plurality of transport on the sprocket, concave type protection suit case install in on the concave type transportation piece, just concave type protection suit in the transportation driving machine transport chain and a plurality of on the transportation sprocket, the transportation metal belt suit in a plurality of on the transportation cylinder, combustion module install in the inboard of concave type transportation piece, a plurality of burner port has been seted up on the transportation metal belt.

3. The apparatus for multi-stage boiler NOx reduction according to claim 2, wherein the screening structure comprises: the screening and returning plate, the screening net, the drainage funnel and the concave collecting block;

the drainage funnel is inserted into the concave collection block and the multi-section type flow-splitting boiler, the screening return plate is obliquely arranged at the joint between the drainage funnel and the concave collection block, and the screening net is arranged on the screening return plate.

4. The apparatus for multi-stage boiler NOx reduction according to claim 3, wherein the flow conditioning assembly comprises: the high-temperature air pump, the low-temperature air pump, the high-temperature shunt pipe, the low-temperature shunt pipe, the plurality of concave air flow adjusting blocks, the plurality of angular shunt shafts, the plurality of angular shunt plates, the plurality of shunt gears, the plurality of shunt moving plates, the plurality of concave moving limiting blocks, the plurality of shunt clamping strips and the plurality of shunt hydraulic push rods are arranged on the high-temperature air pump;

the high-temperature air pump is arranged on one side of a high-temperature coiling pipe on the transfer box, the low-temperature air pump is arranged on one side of a low-temperature coiling pipe on the transfer box, a plurality of concave airflow regulating blocks are horizontally and parallelly arranged on the inner side of the multi-section flow splitting boiler, the concave airflow regulating blocks are positioned on two sides of the concave combustion flow splitting plate, a plurality of angle flow splitting shafts are respectively inserted on the concave airflow regulating blocks through bearings, a plurality of angle flow splitting plates are respectively arranged on the angle flow splitting shafts, a plurality of splitting gears are respectively arranged on the angle flow splitting shafts, a plurality of concave movement limiting blocks are arranged on the inner side of the multi-section flow splitting boiler, a plurality of concave movement limiting blocks are respectively positioned on the side walls of the movable plates of the concave airflow regulating blocks, and a plurality of splitting gears are respectively movably inserted on the inner sides of the concave movement limiting blocks, a plurality of the reposition of redundant personnel card strip is installed respectively in a plurality of on the reposition of redundant personnel movable plate, and a plurality of the reposition of redundant personnel card strip respectively with a plurality of reposition of redundant personnel gear wheel toothing, a plurality of reposition of redundant personnel hydraulic rod installs respectively in a plurality of on the concave type removal stopper, and a plurality of reposition of redundant personnel hydraulic rod propelling end is connected respectively in a plurality of on the reposition of redundant personnel movable plate, the high temperature shunt tubes install in on the high temperature aspiration pump, just the high temperature shunt tubes connect in on the concave type air current regulating block of multistage formula reposition of redundant personnel boiler discharge gate department, the low temperature shunt tubes install in on the low temperature aspiration pump, just the low temperature shunt tubes connect in on the concave type air current regulating block of multistage formula reposition of redundant personnel boiler feed gate department.

5. The apparatus for multi-stage boiler NOx reduction according to claim 4, wherein the combustion assisting assembly comprises: the gas-fired boiler comprises a gas tank, a gas extraction pump, a gas split-flow drainage pipe, a gas valve, a plurality of gas disks and a gas bracket;

the gas jar install in on the lateral wall of multistage formula reposition of redundant personnel boiler, the gas aspiration pump install in on the gas jar, the gas valve install in on the gas aspiration pump, the gas support mounting in on the concave type transport block, a plurality of the gas dish install in on the gas support, the gas reposition of redundant personnel drainage tube install in on the gas aspiration pump, just the gas reposition of redundant personnel drainage tube is connected in a plurality of on the gas dish.

6. The apparatus for multi-stage NOx reduction for a boiler according to claim 5, wherein the burner assembly comprises: the circulating shunt pipe and the plurality of circulating bearing blocks;

the circulation shunt tubes are connected to the inner sides of the conveying rollers through a plurality of circulation bearing blocks, and the circulation shunt tubes are connected to the low-temperature coiling pipes.

7. A method and equipment for reducing NOx of a boiler in a multi-stage mode comprise the following operation steps: s1, screening coal raw materials; step S2, transportation and combustion; step S3, conducting high-temperature smoke; step S4, recovering and draining the heat of the high-temperature smoke; step S5, conducting high-temperature and low-temperature airflow; step S6, secondary combustion supporting;

step S1: screening the coal raw material to ensure that the size of the coal is larger than that of a combustion hole on a metal conveying belt;

step S2: burning the coal raw material on the conveying metal belt through a combustion assembly;

step S3: guiding air on one side of the multi-section type flow-dividing boiler screening structure to a high-temperature coiled pipe, a low-temperature coiled pipe and a multi-section type flow-dividing boiler discharge port;

step S4: the air is guided to the inner side of the transfer box, so that the heat on the high-temperature winding pipe and the low-temperature winding pipe is recovered, the loss of the heat is avoided, and the generation of NOX is reduced;

step S5: guiding the preheated gas into the multi-section type flow dividing boiler, and changing the gas flow through the gas flow adjusting assembly so as to change the gas flow in the multi-section type flow dividing boiler;

step S6: and carrying out secondary combustion on coal and gas at the discharge outlet of the multi-section type flow-dividing boiler.

8. The method and apparatus for multi-stage reducing NOx in a boiler according to claim 7, wherein the step S3 is to recover the gas generated by the primary combustion by a circulating air pump, and to dissipate the heat generated by the recovery, so as to reduce the temperature of the gas.

9. The method and apparatus for multi-stage NOx reduction in a boiler according to claim 8, wherein the step S4, the lack of oxygen and the low temperature in the main combustion area suppress the generation of NOx by decreasing the air ratio to the range of 0.75-0.9 during the preliminary combustion.

10. The method and apparatus for multi-stage reducing of NOx in a boiler according to claim 9, wherein in step S6, the post-combustion coal is supplemented with oxygen, and the pulverized coal in the boiler is fully combusted by supplementing excess air in the later stage of combustion.

Technical Field

The invention relates to the technical field of boilers in thermal power plants, in particular to a method and equipment for reducing NOx of a boiler in a multi-section mode.

Background

In order to save conventional energy and reduce pollution, the rational utilization of biomass energy has been increasingly regarded. The biomass and coal-fired coupled power generation has the advantages of high operation efficiency, good economic benefit, low pollution emission, low fuel supply risk and the like, and has important practical significance for reinforcing the complementary advantages of biomass resources and coal-fired power plants, realizing the flexibility of coal-electricity fuels and reducing haze weather caused by open burning of agricultural and forestry waste residues.

The biomass and coal-fired coupled power generation can be realized by direct co-firing, indirect co-firing and parallel co-firing. The indirect biomass co-combustion has the advantages of wide fuel application range, small change to the existing boiler, higher operation flexibility and application to the existing coal-fired boilers of power stations with different capacities, and gets wide attention at home and abroad. The indirect mixed combustion is to gasify the biomass into synthesis gas and then send the synthesis gas into a furnace for combustion. Biomass gasification refers to a process in which biomass fuel is converted into combustible gas through a series of thermochemical reaction processes in the presence of a gasification medium. The main effective components of the combustible gas generated by biomass gasification are CO, H2, CH4 and part of alkane gas.

Therefore, the blending combustion position of the biomass gas must be reasonably selected, so that the biomass gas can be fully combusted, the NOx emission in a reduction region can be reduced, the biomass gas blending combustion can reach the maximum value, and a unit can reach the most economical and optimal operation.

Disclosure of Invention

The technical scheme of the invention for realizing the aim is as follows: an apparatus for multi-stage boiler NOx reduction, comprising: the multi-section type flow distribution boiler comprises a multi-section type flow distribution boiler and a transfer box, wherein the transfer box is arranged on the multi-section type flow distribution boiler, a transportation combustion structure and a screening structure are arranged in the multi-section type flow distribution boiler, a transfer control structure is arranged on the transfer box, and the transfer control structure is connected to the transportation combustion structure;

the transfer control structure comprises: the device comprises a combustion concave splitter plate, a transfer splitter plate, a pair of horn-shaped collection inner boxes, a high-temperature coiled pipe, a low-temperature coiled pipe, a circulating air pump, an air flow adjusting assembly and a combustion auxiliary assembly;

the utility model discloses a multistage formula boiler of dividing is including the concave flow distribution plate of burning, including the concave flow distribution plate of burning install in the inboard of multistage formula reposition of redundant personnel boiler, the reposition of redundant personnel flow distribution plate install in the inboard of transfer case, it is a pair of loudspeaker type collection inner box is inserted respectively in the inboard of multistage formula reposition of redundant personnel boiler, and a pair of loudspeaker type collection inner box is located respectively on the both sides of the concave flow distribution plate of burning, high temperature coiled tube and low temperature coiled tube install in the inboard of transfer case, just high temperature coiled tube and low temperature coiled tube connect respectively in a pair of on the loudspeaker type collection inner box, the circulating air pump install in on the transfer flow distribution plate, just the circulating air pump connect in on high temperature coiled tube and the low temperature coiled tube.

Preferably, the transportation combustion structure comprises: the device comprises a concave transportation block, a plurality of transportation rollers, a plurality of transportation chain wheels, a transportation chain, a transportation driving machine, a concave protective sleeve box, a transportation metal belt and a combustion assembly;

the transportation cylinder pass through the bearing cartridge in on the concave type transportation piece, the transportation driving machine install in on the concave type transportation piece, a plurality of transportation sprocket installs respectively in a plurality of the transportation cylinder and on the drive end of transportation driving machine, the transportation chain suit in a plurality of transport on the sprocket, concave type protection suit case install in on the concave type transportation piece, just concave type protection suit in the transportation driving machine transport chain and a plurality of transport on the sprocket, the transportation metal belt suit in a plurality of transport on the cylinder, burning component install in the inboard of concave type transportation piece, a plurality of burning hole has been seted up on the transportation metal belt.

Preferably, the screening structure comprises: the screening and returning plate, the screening net, the drainage funnel and the concave collecting block;

the drainage funnel is inserted into the concave collection block and the multi-section type flow-splitting boiler, the screening return plate is obliquely arranged at the joint between the drainage funnel and the concave collection block, and the screening net is arranged on the screening return plate.

Preferably, the airflow adjusting assembly comprises: the high-temperature air pump, the low-temperature air pump, the high-temperature shunt pipe, the low-temperature shunt pipe, the plurality of concave air flow adjusting blocks, the plurality of angle shunt shafts, the plurality of angle shunt plates, the plurality of shunt gears, the plurality of shunt moving plates, the plurality of concave moving limiting blocks, the plurality of shunt clamping strips and the plurality of shunt hydraulic push rods;

the high-temperature air pump is arranged on one side of a high-temperature coiled pipe on the transfer box, the low-temperature air pump is arranged on one side of a low-temperature coiled pipe on the transfer box, a plurality of concave airflow adjusting blocks are horizontally and parallelly arranged on the inner side of the multi-section flow dividing boiler, a plurality of concave airflow adjusting blocks are positioned on two sides of the concave combustion flow dividing plate, a plurality of angle flow dividing shafts are respectively inserted on the plurality of concave airflow adjusting blocks through bearings, a plurality of angle flow dividing plates are respectively arranged on the plurality of angle flow dividing shafts, a plurality of flow dividing gears are respectively arranged on the plurality of angle flow dividing shafts, a plurality of concave movement limiting blocks are arranged on the inner side of the multi-section flow dividing boiler, and a plurality of concave movement limiting blocks are respectively positioned on the side walls of the concave airflow adjusting blocks, the plurality of shunt moving plates are respectively movably inserted into the inner sides of the plurality of concave moving limiting blocks, the plurality of shunt clamping strips are respectively arranged on the plurality of shunt moving plates, and a plurality of the shunting clamping strips are respectively meshed with a plurality of the shunting gear pulleys, a plurality of the shunting hydraulic push rods are respectively arranged on a plurality of the concave type movable limiting blocks, and the pushing ends of the shunt hydraulic push rods are respectively connected on the shunt moving plates, the high-temperature shunt tubes are arranged on the high-temperature air pump, the high-temperature shunt pipe is connected to the concave air flow adjusting block at the discharge port of the multi-section shunt boiler, the low-temperature shunt pipe is arranged on the low-temperature air pump, and the low-temperature shunt pipe is connected to the concave airflow adjusting block at the feed inlet of the multi-section shunt boiler.

Preferably, the combustion assistance assembly comprises: the gas-fired boiler comprises a gas tank, a gas extraction pump, a gas split-flow drainage pipe, a gas valve, a plurality of gas disks and a gas bracket;

the gas jar install in on the lateral wall of multistage formula reposition of redundant personnel boiler, the gas air pump install in on the gas jar, the gas valve install in on the gas air pump, the gas support mounting in on the concave type transportation piece, a plurality of the gas dish install in on the gas support, the gas reposition of redundant personnel drainage tube install in on the gas air pump, just the gas reposition of redundant personnel drainage tube connect in a plurality of on the gas dish.

Preferably, the combustion assembly comprises: the circulating branch pipes and the circulating bearing blocks are arranged on the bearing block;

the circulation shunt tubes are connected to the inner sides of the conveying rollers through a plurality of circulation bearing blocks, and the circulation shunt tubes are connected to the low-temperature coiling pipes.

A method and equipment for reducing NOx of a boiler in a multi-stage mode comprise the following operation steps: s1, screening coal raw materials; step S2, transportation and combustion; step S3, conducting high-temperature smoke; step S4, recovering and draining the high-temperature smoke heat; step S5, conducting high-temperature and low-temperature airflow; step S6, secondary combustion supporting;

step S1: screening the coal raw material to ensure that the size of the coal is larger than that of the combustion holes on the transportation metal belt;

step S2: burning the coal raw material on the conveying metal belt through a combustion assembly;

step S3: guiding air on one side of the multi-section type flow-dividing boiler screening structure to a high-temperature coiled pipe, a low-temperature coiled pipe and a multi-section type flow-dividing boiler discharge port;

step S4: the air is guided to the inner side of the transfer box, so that the heat on the high-temperature coil pipe and the low-temperature coil pipe is recovered, the loss of the heat is avoided, and the generation of NOX is reduced;

step S5: guiding the preheated gas into the multi-section type flow dividing boiler, and changing the gas flow through the gas flow adjusting component so as to change the gas flow in the multi-section type flow dividing boiler;

step S6: and carrying out secondary combustion on coal and gas at the discharge outlet of the multi-section type flow-dividing boiler.

And step S3, recovering the gas generated by the primary combustion through a circulating air pump, and dissipating the recovered heat to reduce the temperature of the gas.

The lack of oxygen and the low temperature of the main combustion zone suppress the generation of NOx by reducing the air ratio in the preliminary combustion process to the range of 0.75 to 0.9 at said step S4.

And step S6, performing oxygen supplementation on the coal subjected to secondary combustion, and fully combusting the pulverized coal in the furnace by supplementing excessive air in the later combustion stage.

The method and the equipment for reducing the NOx of the boiler in a multi-section way, which are manufactured by the technical scheme of the invention, carry out flow-dividing combustion on coal through a transfer control structure, divide the coal into a main combustion area and a compensation combustion area, reduce the excess air coefficient of the boiler to the range of 0.75-0.9 in the main combustion area, inhibit the generation of NOx due to the oxygen deficiency and the low temperature of the main combustion area, and ensure that pulverized coal in the boiler is fully combusted in the compensation combustion area by supplementing excess air, wherein the common burnout component accounts for 20-30% of the total air volume of the boiler.

Drawings

FIG. 1 is a schematic diagram of the structure of the multi-stage method and apparatus for reducing NOx in a boiler according to the present invention.

FIG. 2 is a side view of the multi-stage NOx reduction method and apparatus of the present invention.

FIG. 3 is a schematic top view of the multi-stage method and apparatus for reducing NOx in a boiler according to the present invention.

Fig. 4 is an enlarged view of a portion "a" in fig. 1.

Fig. 5 is an enlarged view of a portion "B" in fig. 1.

In the figure: 1. a multi-section split-flow boiler; 2. a transfer box; 3. a combustion concave splitter plate; 4. a middle transfer splitter plate; 5. a horn-shaped collection inner box; 6. a high temperature coiled tubing; 7. a cryogenic coiled tubing; 8. a circulating air pump; 9. a concave transport block; 10. a transport drum; 11. a transport sprocket; 12. a transport chain; 13. a transport drive; 14. a concave protective sleeve box; 15. transporting the metal belt; 16. sieving the returned plates; 17. screening the net; 18. a drainage funnel; 19. a concave collection block; 20. a high temperature air pump; 21. a cryogenic air pump; 22. a high temperature shunt tube; 23. a low temperature shunt tube; 24. a concave air flow regulating block; 25. an angle shunt shaft; 26. an angle splitter plate; 27. a shunt gear; 28. a shunt moving plate; 29. a concave movable limiting block; 30. shunting and clamping strips; 31. and a hydraulic push rod is branched.

Detailed Description

The invention will be described in detail with reference to the accompanying drawings, as shown in fig. 1-5, an apparatus for multi-stage reduction of boiler NOx comprising: the multi-section type flow distribution boiler comprises a multi-section type flow distribution boiler 1 and a transfer box 2, wherein the transfer box 2 is installed on the multi-section type flow distribution boiler 1, a transportation combustion structure and a screening structure are installed in the multi-section type flow distribution boiler 1, a transfer control structure is installed on the transfer box 2, and the transfer control structure is connected to the transportation combustion structure; the transfer control structure comprises: the device comprises a combustion concave-shaped splitter plate 3, a transfer splitter plate 4, a pair of horn-shaped collection inner boxes 5, a high-temperature coiled pipe 6, a low-temperature coiled pipe 7, a circulating air pump 8, an air flow adjusting assembly and a combustion auxiliary assembly; the combustion concave splitter plate 3 is installed on the inner side of the multi-section type splitter boiler 1, the transfer splitter plate 4 is installed on the inner side of the transfer box 2, the pair of horn-shaped collection inner boxes 5 are respectively inserted into the inner side of the multi-section type splitter boiler 1, the pair of horn-shaped collection inner boxes 5 are respectively located on two sides of the combustion concave splitter plate 3, the high-temperature coiled pipe 6 and the low-temperature coiled pipe 7 are installed on the inner side of the transfer box 2, the high-temperature coiled pipe 6 and the low-temperature coiled pipe 7 are respectively connected to the pair of horn-shaped collection inner boxes 5, the circulating air pump 8 is installed on the transfer splitter plate 4, and the circulating air pump 8 is connected to the high-temperature coiled pipe 6 and the low-temperature coiled pipe 7; the transportation combustion structure comprises: the device comprises a concave transport block 9, a plurality of transport rollers 10, a plurality of transport chain wheels 11, a transport chain 12, a transport driving machine 13, a concave protective sleeve box 14, a transport metal belt 15 and a combustion assembly; the transport rollers 10 are inserted into the concave transport block 9 through bearings, the transport driving machine 13 is mounted on the concave transport block 9, the transport chain wheels 11 are mounted on the transport rollers 10 and the drive ends of the transport driving machine 13 respectively, the transport chains 12 are sleeved on the transport chain wheels 11, the concave protective casing 14 is mounted on the concave transport block 9, the concave protective casing 14 is sleeved on the transport driving machine 13, the transport chains 12 and the transport chain wheels 11, the transport metal belts 15 are sleeved on the transport rollers 10, the combustion assembly is mounted on the inner side of the concave transport block 9, and the transport metal belts 15 are provided with combustion holes; the screening structure includes: a sieving return plate 16, a sieving net 17, a drainage funnel 18 and a concave collecting block 19; the concave collecting block 19 is installed on the multi-section type flow-splitting boiler 1, the drainage funnel 18 is inserted into the concave collecting block 19 and the multi-section type flow-splitting boiler 1, the sieving return plate 16 is obliquely installed at the joint between the drainage funnel 18 and the concave collecting block 19, and the sieving net 17 is installed on the sieving return plate 16; the airflow regulating assembly comprises: the high-temperature air pump 20, the low-temperature air pump 21, the high-temperature shunt tube 22, the low-temperature shunt tube 23, a plurality of concave air flow adjusting blocks 24, a plurality of angular shunt shafts 25, a plurality of angular shunt plates 26, a plurality of shunt gears 27, a plurality of shunt moving plates 28, a plurality of concave moving limiting blocks 29, a plurality of shunt clamping strips 30 and a plurality of shunt hydraulic push rods 31; the high-temperature air pump 20 is installed on one side of a high-temperature coiling pipe 6 on the transit box 2, the low-temperature air pump 21 is installed on one side of a low-temperature coiling pipe 7 on the transit box 2, a plurality of concave air flow adjusting blocks 24 are horizontally installed on the inner side of the multi-section diversion boiler 1 in parallel, a plurality of concave air flow adjusting blocks 24 are positioned on two sides of the combustion concave diversion plate 3, a plurality of angle diversion shafts 25 are respectively inserted on the plurality of concave air flow adjusting blocks 24 through bearings, a plurality of angle diversion plates 26 are respectively installed on the plurality of angle diversion shafts 25, a plurality of diversion gears 27 are respectively installed on the plurality of angle diversion shafts 25, a plurality of concave movement limiting blocks 29 are installed on the inner side of the multi-section diversion boiler 1, and a plurality of concave movement limiting blocks 29 are respectively positioned on the side walls of the plurality of concave air flow adjusting blocks 24, the plurality of shunting moving plates 28 are respectively movably inserted inside the plurality of concave moving stoppers 29, the plurality of shunting clamping strips 30 are respectively installed on the plurality of shunting moving plates 28, and a plurality of the shunting clamping strips 30 are respectively engaged with a plurality of the shunting gears 27, a plurality of the shunting hydraulic push rods 31 are respectively arranged on a plurality of the concave type movable limiting blocks 29, the pushing ends of the plurality of shunting hydraulic push rods 31 are respectively connected to the plurality of shunting moving plates 28, the high-temperature shunting pipe 22 is arranged on the high-temperature air pump 20, the high-temperature shunt pipe 22 is connected to the concave air flow adjusting block 24 at the discharge port of the multi-section shunt boiler 1, the low-temperature shunt pipe 23 is installed on the low-temperature air pump 21, the low-temperature shunt pipe 23 is connected to the concave airflow adjusting block 24 at the feed inlet of the multi-section shunt boiler 1; the combustion assistance assembly includes: the gas-fired boiler comprises a gas tank, a gas extraction pump, a gas split-flow drainage pipe, a gas valve, a plurality of gas discs and a gas support; the gas tank is mounted on the side wall of the multi-section type flow-splitting boiler 1, the gas suction pump is mounted on the gas tank, the gas valve is mounted on the gas suction pump, the gas support is mounted on the concave transport block 9, the plurality of gas disks are mounted on the gas support, the gas flow-splitting drainage pipe is mounted on the gas suction pump, and the gas flow-splitting drainage pipe is connected to the plurality of gas disks; the combustion assembly includes: the circulating shunt pipe and a plurality of circulating bearing blocks; the circulation shunt tubes are connected to the inner sides of the transport drums 10 through a plurality of circulation bearing blocks, and the circulation shunt tubes are connected to the low-temperature coiling tube 7.

A method and equipment for reducing NOx of a boiler in a multi-stage mode comprise the following operation steps: s1, screening coal raw materials; step S2, transportation and combustion; step S3, conducting high-temperature smoke; step S4, recovering and draining the heat of the high-temperature smoke; step S5, conducting high-temperature and low-temperature airflow; step S6, secondary combustion supporting;

step S1: the coal raw material is screened to ensure that the size of the coal is larger than that of the combustion holes on the transportation metal belt 15;

step S2: burning the coal raw material on the conveying metal belt 15 through a combustion assembly;

step S3: guiding air on one side of the screening structure of the multi-section type flow-splitting boiler 1 to a high-temperature coiled pipe 6, a low-temperature coiled pipe 7 and a discharge port of the multi-section type flow-splitting boiler 1;

step S4: the heat on the high-temperature coiled pipe 6 and the low-temperature coiled pipe 7 is recovered by guiding the air to the inner side of the transfer box 2, so that the loss of the heat is avoided, and the generation of NOX is reduced at the same time;

step S5: guiding the preheated gas into the multi-section flow splitting boiler 1, and changing the gas flow through the gas flow adjusting assembly so as to change the gas flow in the multi-section flow splitting boiler 1;

step S6: and carrying out secondary combustion on the coal and the gas at the discharge outlet of the multi-section type flow-splitting boiler 1.

In step S3, the gas generated by the primary combustion is recovered by the air circulation pump 8, and the recovered heat is dissipated, thereby lowering the temperature of the gas.

The lack of oxygen and the low temperature of the main combustion zone suppress the generation of NOx by reducing the air ratio in the preliminary combustion process to the range of 0.75 to 0.9 at said step S4.

And step S6, performing oxygen supplementation on the coal subjected to secondary combustion, and fully combusting the pulverized coal in the furnace by supplementing excessive air in the later combustion stage.

All the electrical components and the adaptive power supply thereof in the present application are connected through a wire by a person skilled in the art, and an appropriate controller should be selected according to actual conditions to meet control requirements, specific connection and control sequence.

Example (b): the coal on the concave transportation block 9 is combusted through a combustion auxiliary assembly in the concave transportation block 9, meanwhile, the boiler is separated through a combustion concave flow distribution plate 3 and is separated into a high-temperature area and a low-temperature area, the high-temperature area is a main combustion area which is connected to a screening structure, coal raw materials are guided to a screening net 17 on a screening return plate 16 through a drainage funnel 18 to screen the coal to a certain extent, the coal with a certain size is guided into a concave collection block 19, a transportation driving machine 13 on the concave transportation block 9 operates to drive a transportation chain wheel 11 on a driving end of a transportation driving machine 13 to rotate, a transportation chain 12 on the transportation chain wheel 11 is driven to rotate through the transportation chain wheel 12, a plurality of transportation chain wheels 11 meshed with the transportation chain wheel are driven to rotate through the transportation chain wheel 11, and a plurality of transportation roller 10 on the transportation chain wheel 11 are driven to rotate respectively, the conveying metal belt 15 on the conveying metal belt is driven by the plurality of conveying rollers 10, the coal sieved on the conveying metal belt 15 is driven by the conveying metal belt 15 to be conveyed, the coal on the conveying metal belt 15 is ignited by the combustion auxiliary assembly, the smoke is guided into the high-temperature coiling pipe 6 by the horn-shaped collecting inner box 5 in the high-temperature area, the smoke in the high-temperature coiling pipe 6 is guided into the low-temperature coiling pipe 7 by the circulating air pump 8, the cooled smoke is guided into the horn-shaped collecting inner box 5 by the low-temperature coiling pipe 7, and the cooled smoke is guided into the low-temperature area of the boiler by the horn-shaped collecting inner box 5; the gas in the high-temperature coiling pipe 6 between the transit diversion plate 4 and the auxiliary combustion box is pumped into the high-temperature diversion pipe 22 by the high-temperature air pump 20, the heat is dissipated to the air shaft by a plurality of high-temperature coiling pipes 6, the high-temperature air is guided to the combustion concave diversion plate 3 and the concave airflow adjusting block 24 in the low-temperature area of the boiler by the high-temperature diversion pipe 22, the diversion hydraulic push rod 31 is pushed to push the diversion moving plate 28 on the end by the operation of the diversion hydraulic push rod 31, the diversion clamping strip 30 on the diversion hydraulic push rod is driven by the diversion moving plate 28, a plurality of diversion gears 27 meshed with the diversion gears are driven to rotate by the diversion clamping strip 30, the angle diversion shafts 25 on the plurality of diversion gears 27 are respectively driven to rotate by the rotation of the plurality of diversion gears 27, the angle diversion plates 26 on the diversion gears are driven by the rotation of the plurality of angle diversion shafts 25, the air flow measured by flowing in the high-temperature flow dividing pipe 22 is respectively subjected to angle adjustment through the rotation of the plurality of angular flow dividing plates 26, so that the effects of controlling the combustion in the boiler and the flow direction of the air flow are achieved, similarly, the low-temperature air in the auxiliary combustion box is pumped to the feed inlet of the boiler through the low-temperature air pump 21, and the coal cannot be completely combusted through the low-temperature and low-flow-rate air, namely, the excess air coefficient of the boiler is reduced to the range of 0.75-0.9 in the main combustion area, the generation of NOx is inhibited by the oxygen deficiency and the low temperature in the main combustion area, the pulverized coal in the boiler is fully combusted through supplementing the excess air in the later stage of combustion, and the general burnout component accounts for 20% -30% of the total air volume of the boiler.

The technical solutions described above only represent the preferred technical solutions of the present invention, and some possible modifications to some parts of the technical solutions will all represent the principles of the present invention, and fall within the protection scope of the present invention.