CN213480213U

CN213480213U - Compact mixes formula ultralow nitrogen combustion device in advance

Info

Publication number: CN213480213U
Application number: CN202022381138.4U
Authority: CN
Inventors: 杨培凯; 朱德辉; 姜赟; 肖楠; 何启理
Original assignee: Guangdong Eacoon Energy Technology Stock Co ltd
Current assignee: Guangzhou Yigao Environmental Protection Equipment Co ltd
Priority date: 2020-10-23
Filing date: 2020-10-23
Publication date: 2021-06-18
Anticipated expiration: 2030-10-23

Abstract

The utility model relates to a burner technical field indicates a compact mixes formula ultralow nitrogen burner in advance especially contains: the device comprises an outer guide pipe, a burner shell, an adjusting device, a primary air pipe, a central gas pipe and a plurality of surrounding combustion assemblies, wherein the burner shell is communicated with the outer guide pipe; the mouth of pipe of play of outer pipe is connected with flue gas water conservancy diversion subassembly, the tuber pipe runs through outer pipe and a tuber pipe cover are established on central gas pipe, the tip of tuber pipe is equipped with the whirl dish, the front end of central gas pipe be equipped with the burner that the whirl dish is adjacent, the burner is equipped with the gas orifice. The utility model discloses thereby combine together air-flue gas in advance and air-fuel in advance two combustion technology in advance on the basis of air, fuel classification technique and further reduce nitrogen oxide's emission.

Description

Compact mixes formula ultralow nitrogen combustion device in advance

Technical Field

The utility model relates to a burner technical field indicates a compact mixes formula ultralow nitrogen burner in advance especially, and it mixes Air-flue Gas in advance and Air-Gas mixes two combustion technology simultaneously and uses in a combustor on Air classification technique (Air staging), Gas classification (Gas staging) technical basis to reduce nitrogen oxide's emission, reach the purpose that the low nitrogen discharged.

Background

Generally, nitrogen oxides (NOx) can be classified into the following: fuel nitrogen oxides (Fuel NOx) formed by oxidation of nitrogen components in the form chemically bound to Fuel during combustion; thermal nitrogen oxides (Thermal NOx) generated by the dissociation of nitrogen in combustion air at high temperatures; and hydrocarbon series fossil fuels rapidly produce fast nitrogen oxides (Prompt NOx) when exposed to high temperature environments in a high concentration state.

Nitrogen oxides (NOx) can negatively affect the atmospheric environment and human life, resulting in frequent occurrence of severe haze polluting weather. Therefore, developers have since long developed low NOx burner technology.

This technology has undergone the following three generations of development:

first generation: the air classification technology is taken as a representative, the air is supplied to the combustion furnace through classification, the rapid oxidation reaction caused by the fuel in the combustion furnace is prevented, the flame temperature is reduced, and the thermal nitrogen oxide is reduced.

And (4) second generation: the gas classification technique is a typical technique in which two streams of injected gas, a central portion (about 5% to 25%) and a peripheral portion (75% to 95%), are separated so that the central portion is in a state where air is excessive and the outside air is insufficient, thereby suppressing an oxidation reaction in the peripheral portion occupying most of the flame, and preventing the temperature of the flame from rising, thereby reducing thermal nitrogen oxides. Although rapid nitrogen oxides may be generated due to the fact that the surrounding flame is in an insufficient state in the air, the flame temperature is ensured to be 1000 ℃ or less by injecting gas to the periphery, so that the function of maintaining the flame and the function of suppressing the generation of rapid NOx can be simultaneously realized.

And a third generation: taking IFGR (internal flue gas Recirculation) as a representative, it is possible to achieve self-Recirculation (Recirculation) of combustion gas in the combustion chamber after primary combustion, allowing the combustion gas and flame to mix, reducing the flame temperature, and thus reducing the thermal nitrogen oxides.

The three technologies are difficult to meet the national requirement of 30mg/Nm3 on ultralow nitrogen emission, and specifically comprise the following steps:

1. the first generation adopts an air staged combustion technology, and the emission of nitrogen oxides of a gas burner is generally about 160mg/Nm 3;

2. the second generation adds fuel and burns the technology in grades on the basis of the air staging combustion technology, the discharge amount of the nitrogen oxide of the gas burner is about 120mg/Nm3 generally;

3. in the third generation, the emission of nitrogen oxides of a gas burner is generally about 80mg/Nm3 on the basis of adopting an air staged combustion technology and fuel staging and an IFGR (internal flue gas recirculation) technology;

today, in the 21 st century, the technologies cannot meet the increasingly strict emission requirements according to the requirements of the national environmental protection law, so that the development of a lower-nitrogen environment-friendly gas combustion technology is needed.

Disclosure of Invention

In order to solve the above problems, an object of the present invention is to provide a compact premixing ultra-low nitrogen combustion apparatus, which combines air-flue gas premixing and air-fuel premixing on the basis of air and fuel classification techniques to further reduce the emission of nitrogen oxides.

In order to achieve the above object, the utility model adopts the following technical scheme:

the utility model provides a compact mixes formula ultralow nitrogen combustion device in advance, its setting on the outer wall of combustion chamber, its characterized in that, compact mixes formula ultralow nitrogen combustion device in advance contains: the device comprises an outer guide pipe, a burner shell, an adjusting device, a primary air pipe, a central gas pipe and a plurality of surrounding combustion assemblies, wherein the burner shell is communicated with the outer guide pipe; wherein,

one end of the outer conduit is inserted into the combustion chamber, and a flue gas guide assembly is connected to an outlet pipe orifice of the outer conduit and is used for introducing air and flue gas into the combustion chamber;

the primary air pipe penetrates through the outer guide pipe and is sleeved on the central gas pipe, a spiral-flow disk is arranged at the end part of the primary air pipe, a combustion head adjacent to the spiral-flow disk is arranged at the front end of the central gas pipe, and the combustion head is provided with a gas spray hole; the fuel gas is jetted from the fuel gas jet hole into a blowpipe to be premixed with air and then jetted into the hearth for combustion;

and the peripheral combustion assemblies penetrate through the outer guide pipe and are uniformly distributed on the periphery of the primary air pipe, and the peripheral combustion assemblies are used for premixing gas and air and injecting the premixed mixed gas into a hearth at a high speed for combustion.

Furthermore, the peripheral combustion assembly comprises an air suction chamber, a mixing pipe and a plurality of peripheral gas pipes, one end of the mixing pipe is inserted into the combustion chamber, the other end of the mixing pipe is communicated with the air suction chamber, and the air suction chamber is provided with a flow guide port;

the peripheral gas pipes are uniformly distributed on the outer ring of the primary air pipe, the front ends of the peripheral gas pipes are provided with reducing gas nozzles, and the gas nozzles are inserted into the air suction chamber.

Further, the flue gas diversion assembly comprises a reducing connecting pipe and a combustor outer ring guide pipe connected with the reducing connecting pipe, and a smoke guide port is arranged between the reducing connecting pipe and the combustor outer ring guide pipe.

Further, the compact premixing type ultralow-nitrogen combustion device further comprises a mounting plate, and the outer guide pipe is fixed on the outer wall of the combustion chamber through the mounting plate.

Further, the compact premixing type ultra-low nitrogen combustion device further comprises a surrounding gas main pipe which is communicated with the surrounding gas pipes.

Furthermore, the flow of the central gas pipe accounts for 10% -15% of the total gas quantity of the whole device, and the flow of the surrounding gas main pipe accounts for 85% -90% of the total gas quantity of the whole device.

Further, the combustion head is a horn-shaped combustion head, and the gas spray holes are formed in the conical inclined edge of the horn-shaped combustion head.

The beneficial effects of the utility model reside in that:

the utility model discloses on air, fuel classification technique basis, with the combustor that air-flue gas mixes technique and air-fuel in advance and mixes the technique and make and fuse, compare with the low nitrogen combustor that adopts IFGR (inside flue gas circulation) technique, can further reduce nitrogen oxide's emission, realize ultralow nitrogen and discharge. The method specifically comprises the following steps:

1. by controlling the mixing ratio of the central gas pipe, the combustion temperature can be lower than the theoretical combustion temperature and also lower than the initial temperature of thermal nitrogen oxide generation, and the generation amount of the nitrogen oxide can be reduced.

2. The flow rate of the gas nozzles of the peripheral gas pipe is controlled, so that the mixed air coefficient is adjustable and less than 1, the combustion temperature is lower than the theoretical combustion temperature and lower than the initial temperature of thermal nitrogen oxide generation, and the generation amount of the nitrogen oxide can be reduced.

3. The flue gas diversion assembly introduces combustion flue gas to form flue gas and air mixed airflow, and reducing atmosphere is formed around the combustion head and around the outlet of the mixing pipe, so that the generation amount of nitrogen oxides is further reduced.

Drawings

Fig. 1 is a schematic side cross-sectional view of the present invention installed on a combustion chamber.

Fig. 2 is a schematic view of the front half of the present invention.

Fig. 3 is a state diagram of the flow of air, fuel gas and combustion flue gas in the present invention.

The reference numbers illustrate: 1. an outer catheter; 2. mounting a plate; 3. a combustion-supporting tuyere; 4. a burner housing; 5. a surrounding gas main; 6. a central gas pipe; 7. an adjustment device; 8. a peripheral gas pipe; 9. a primary air duct; 10. a gas nozzle; 11. a flow guide port; 12. an air suction chamber; 13. a mixing tube; 14. a spinning disk; 15. a burner head; 16. a burner outer ring conduit; 17. a smoke guide port; 18. reducing the diameter of the connecting pipe.

Detailed Description

Referring to fig. 1-3, the present invention relates to a compact premixing ultra-low nitrogen combustion apparatus disposed on an outer wall (furnace wall) of a combustion chamber, the compact premixing ultra-low nitrogen combustion apparatus comprising: an outer conduit 1, a burner housing 4, an adjusting device 7, a primary air pipe 9 and a central gas pipe 6, wherein,

an outer duct 1 having one end inserted into the combustion chamber and the other end communicating with the burner housing 4; the outer conduit 1 is used for introducing secondary air A21 and flue gas C into the combustion chamber;

the combustor shell 4 is provided with a combustion-supporting air port 3, and combustion-supporting air enters the combustor shell 4 through the combustion-supporting air port 3 and is divided into primary air A1 and secondary air A2; wherein, the gas of the primary air A1 and the secondary air A2 are both air;

the primary air pipe 9 penetrates through the outer guide pipe 1, and the adjusting device 7 is used for adjusting the air quantity of primary air A1 entering the primary air pipe 9;

the central gas pipe 6 is inserted into the primary air pipe 9, the end part of the central gas pipe 6 is provided with a horn-shaped combustion head 15, the conical oblique edge of the horn-shaped combustion head 15 is provided with a gas spray hole, and gas is injected into the primary air pipe 9 from the gas spray hole at high speed to realize gas-air premixing; a swirl disk 14 is arranged at the end part of the primary air pipe 9, and the swirl disk 14 is adjacent to the horn-shaped burner head 15; premixed gas and air are injected into the hearth at high speed through the cyclone disk 14 for combustion.

The compact premixing type ultralow-nitrogen combustion device further comprises an air suction chamber 12, a mixing pipe 13 and a plurality of peripheral gas pipes 8, wherein one end of the mixing pipe 13 is inserted into a combustion chamber (also called a hearth), the other end of the mixing pipe 13 is communicated with the air suction chamber 12, and the air suction chamber 12 is provided with a flow guide port 11;

the peripheral gas pipes 8 are uniformly distributed on the outer ring of the primary air pipe 9, the front ends of the peripheral gas pipes 8 are provided with reducing gas nozzles 10, and the gas nozzles 10 are inserted into the air suction chamber 12; the gas is used as an injection medium and is jetted from the gas nozzle 10 to the air suction chamber 12, negative pressure is caused in the air suction chamber 12 due to the rapid flowing of the medium, so that a large amount of ambient air A22 is sucked through the flow guide port 11 and is rapidly mixed with the gas, and the mixed gas and air are jetted into a hearth at a high speed through the mixing pipe 13 for combustion;

in the above solution, the gas nozzle 10 with a reduced diameter can make the gas flow in the mixing pipe 13 fast.

It should be noted that the entire surrounding gas pipe 8 and the mixing pipe 13 extend through the outer pipe 1.

The outlet pipe mouth of the outer conduit 1 is connected with a reducing connecting pipe 18, the reducing connecting pipe 18 is connected with a combustor outer ring conduit 16, a smoke guide port 17 is arranged between the reducing connecting pipe 18 and the combustor outer ring conduit 16, secondary air A21 forms high-speed air flow at the outlet of the reducing connecting pipe 18, negative pressure is caused at the smoke guide port 17, then smoke C around a combustion chamber is sucked in a large amount and is rapidly mixed with air, the pre-mixing of the smoke and the air is realized, and the premixed mixed gas is injected into a hearth at high speed to participate in combustion.

The secondary air a2 may be divided into a secondary air a21 and a secondary air a22 according to the position through which the secondary air flows, the secondary air a21 is located in the diameter-reduced connecting pipe 18, and the secondary air a22 is located around the suction chamber 12.

Further, the compact premixing type ultra-low nitrogen combustion device further comprises a mounting plate 2, and the outer guide pipe 1 is fixed on the outer wall of the combustion chamber through the mounting plate 2.

Further, the compact premixing type ultra-low nitrogen combustion device further comprises a surrounding gas main pipe 5 which is communicated with a plurality of surrounding gas pipes 8.

Further, the flow of the central gas pipe 6 accounts for 10% -15% of the total gas quantity of the whole device, and the flow of the peripheral gas main pipe 5 accounts for 85% -90% of the total gas quantity of the whole device.

The working principle is as follows:

as shown in fig. 3, the combustion air a is divided into primary air a1 and secondary air a2 by the adjusting device 7 in the burner housing 4; the primary air forms primary air flow A1 in the primary air pipe 9, the gas in the central gas pipe 6 forms gas flow B1, the gas flow B1 is jetted into the primary air flow A1 from a gas jet hole at a high speed, two gas flows are mixed to form A1+ B1 and then are jetted into the combustion chamber through the swirling disc 14 at a high speed, the combustion temperature can be lower than the theoretical combustion temperature and lower than the initial temperature of thermal nitrogen oxide generation by controlling the proportion of the primary air A1, meanwhile, the combustion gas of high-speed swirling flow can be wrapped by the combustion smoke around the combustion chamber, and the generation amount of the nitrogen oxide can be further reduced.

The gas in the surrounding gas pipe 8 forms a gas flow B2, a high-speed jet flow is formed at the gas nozzle 10 with the diameter reduced, a large amount of surrounding air A22 is sucked, two gas flows are mixed into A22+ B2 and then are injected into the combustion chamber at a high speed through the mixing pipe 13, the mixed air coefficient is less than 1, the combustion temperature is also lower than the theoretical combustion temperature and lower than the initial temperature for generating thermal nitrogen oxides, and meanwhile, the high-speed combustion gas can be rolled up with the combustion smoke around the combustion chamber, so that the generation amount of the nitrogen oxides can be further reduced.

The overfire air flow a21 in the reducing connection pipe 18 forms a high-speed air flow at the outlet of the reducing connection pipe 18, and largely sucks the combustion flue gas C introduced through the smoke guide 17 to form a flue gas-air mixed flow, and a reducing atmosphere can be formed between the combustion head 15 and the outlet of the mixing pipe 13, thereby further reducing the generation amount of nitrogen oxides.

The utility model has the advantages that:

1. by controlling the mixing ratio of the central gas pipe 6, the combustion temperature can be lower than the theoretical combustion temperature and also lower than the initial temperature of thermal nitrogen oxide generation, and the generation amount of the nitrogen oxide can be reduced.

2. The flow rate of the gas nozzles 10 of the peripheral gas pipe 8 is controlled, so that the mixed air coefficient is adjustable and less than 1, the combustion temperature is lower than the theoretical combustion temperature and lower than the initial temperature of thermal nitrogen oxide generation, and the generation amount of the nitrogen oxide can be reduced.

3. The flue gas diversion assembly introduces combustion flue gas to form a flue gas and air mixed gas flow, and a reducing atmosphere is formed around the combustion head 15 and around the outlet of the mixing pipe 13, so that the generation amount of nitrogen oxides is further reduced.

The above embodiments are only for describing the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention, and various modifications and improvements made by the technical solution of the present invention by those skilled in the art are all within the scope of the present invention as defined by the claims.

Claims

1. The utility model provides a compact mixes formula ultralow nitrogen combustion device in advance, its setting on the outer wall of combustion chamber, its characterized in that, compact mixes formula ultralow nitrogen combustion device in advance contains: the device comprises an outer guide pipe, a burner shell, an adjusting device, a primary air pipe, a central gas pipe and a plurality of surrounding combustion assemblies, wherein the burner shell is communicated with the outer guide pipe; wherein,

2. The compact pre-mixing type ultra-low nitrogen combustion device according to claim 1, wherein the peripheral combustion assembly comprises an air suction chamber, a mixing pipe and a plurality of peripheral gas pipes, one end of the mixing pipe is inserted into the combustion chamber, the other end of the mixing pipe is communicated with the air suction chamber, and the air suction chamber is provided with a flow guide port;

3. The compact pre-mixing type ultra-low nitrogen combustion device according to claim 2, wherein the flue gas guiding assembly comprises a reducing connection pipe and a combustor outer ring conduit connected with the reducing connection pipe, and a smoke guide port is arranged between the reducing connection pipe and the combustor outer ring conduit.

4. The compact pre-mixed ultra-low nitrogen combustion device according to claim 3, further comprising a mounting plate, wherein the outer conduit is fixed to an outer wall of the combustion chamber through the mounting plate.

5. The compact pre-mixed ultra-low nitrogen combustion device according to claim 4, further comprising a peripheral gas main, which is in communication with a plurality of said peripheral gas pipes.

6. The compact pre-mixing type ultra-low nitrogen combustion device according to claim 5, wherein the flow rate of the central gas pipe is 10% -15% of the total gas flow rate of the whole device, and the flow rate of the surrounding gas main pipe is 85% -90% of the total gas flow rate of the whole device.

7. The compact premixed ultra-low nitrogen combustion device according to claim 1, wherein the combustion head is a trumpet-shaped combustion head, and the gas injection holes are arranged on the conical bevel edge of the trumpet-shaped combustion head.