A low nitrogen gas burner
By designing the internal and external two-layer gas channels and three-stage combustion air channel structure of low-nitrogen gas burner, the multi-stage distribution and hedging injection of gas and air during boiler combustion is realized, and the problem of high nitrogen oxide emissions in the existing technology is solved. , reduce NOx emissions and burner operating costs.
Patent Information
- Application Number
- CN202010869224.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2020-08-26
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2040-08-26
AI Technical Summary
When existing boilers reduce nitrogen oxide emissions, investment costs and equipment operation and maintenance costs are high, and it is difficult to achieve low NOx emissions on the basis of ensuring high combustion efficiency.
Design a low-nitrogen gas burner, adopting two-layer gas channels and three-stage combustion air channel structures, and realize multi-stage distribution and hedging injection of gas and air through the central inner gas gun and the outer multi-gun injection structure, promoting rapid Combustion is uniformly and the combustion temperature is controlled through the rotating airflow structure to reduce nitrogen oxide emissions.
It achieves low NOx emissions on the basis of high combustion efficiency, reduces nitrogen oxide emissions to less than 50mg/Nm3, reduces the investment and maintenance costs of the burner, and ensures the stability of the burner and the temperature field uniformity in the furnace.
Smart Images
Figure CN112032714B_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a low-nitrogen gas burner, belonging to the technical field of boiler design and manufacturing. Background Art
[0002] With the increasing attention paid to environmental issues, the emission limits of air pollutants from boilers are becoming increasingly stringent. Beijing DB11 / 139-2015 "Boiler Air Pollutant Emission Standards" requires that the nitrogen oxide emissions of newly built gas boilers after April 1, 2017 be reduced to 30mg / m 3 Shanghai DB31 / 387-2018 "Boiler Air Pollutant Emission Standard" stipulates that from October 1, 2020, gas boiler nitrogen oxide emissions will be implemented at 50mg / m 3 standard limit.
[0003] Therefore, the technical problem that urgently needs to be solved in this technical field is how to reduce the investment cost of denitrification after boiler combustion and the equipment operation and maintenance costs. By analyzing the nitrogen oxide generation mechanism of gas boilers and adopting reasonable structural design, the purpose of emission reduction in boiler combustion can be achieved, and low NOx emissions can be achieved on the basis of ensuring high combustion efficiency. Summary of the invention
[0004] The purpose of the present invention is to solve the technical problem of how to achieve low NOx emissions on the basis of ensuring high combustion efficiency.
[0005] In order to achieve the purpose of solving the above-mentioned problems, the technical solution adopted by the present invention is to provide a low-nitrogen gas burner, including a gas channel, a combustion-supporting air channel and a bellows; the gas channel is arranged in two layers, inner and outer, and the gas channel is arranged in the combustion-supporting air channel; a combustion-supporting air channel is arranged between the inner and outer layers of the gas channels; the combustion-supporting air channel is connected to the bellows, and an air duct inlet is arranged in the bellows.
[0006] Preferably, the combustion-supporting air channel comprises a central primary air channel, an inner secondary air channel and an outer secondary air channel; the central axes of the central primary air channel, the inner secondary air channel and the outer secondary air channel coincide with each other.
[0007] Preferably, the inner gas channel of the gas channel is provided with a central inner gas gun; the central inner gas gun is sleeved inside the central primary air channel.
[0008] Preferably, an inclined surface is provided at an end of the central inner layer gas gun close to one end in the furnace, and an angle is formed between the inclined surface and the central axis of the central inner layer gas gun; and an air injection hole is provided on the inclined surface.
[0009] Preferably, an inner secondary air channel is provided on the outer periphery of the central primary air channel, and a swirl blade is provided at an outlet of one end of the inner secondary air channel close to the furnace.
[0010] Preferably, an outer secondary air channel is provided on the outer periphery of the inner secondary air channel; and an outer layer gas channel of the gas channel is provided in the outer secondary air channel.
[0011] Preferably, the outer gas channel is configured as an outer gas gun connected to a gas collecting box; one end of the outer gas gun close to the furnace is adjacent to an outlet of the inner secondary air channel close to the furnace.
[0012] Preferably, the outer gas gun is provided with a T-shaped or / and L-shaped nozzle at one end close to the furnace; and a gas spray hole is provided on the nozzle.
[0013] Preferably, the central primary air channel is set as a DC air channel, the inner secondary air channel is set as a swirl air channel, and the outer secondary air channel is set as a DC air channel.
[0014] Preferably, the outer gas gun is provided with a nozzle which can form a counter-flow between the outer gas and the swirl wind in the inner secondary air channel and can rotate at any angle around the center axis of the outer gas gun itself.
[0015] Compared with the prior art, the present invention has the following beneficial effects:
[0016] The present invention provides a novel low-nitrogen gas burner, wherein the burner gas is divided into two layers, the inner and outer layers, the combustion-supporting air is divided into three levels, the central inner layer gas is located in the central primary air channel, and the outer layer gas is a multi-gun injection structure, which is located in the secondary air channel. The multi-level distribution of fuel and air and the multi-gun counter-injection injection enable the gas and the combustion-supporting air to be mixed evenly and burned quickly, while dispersing the fuel, so as to achieve the purpose of controlling the overall and local combustion temperature and reducing nitrogen oxide emissions. The central primary air channel is a direct current air channel, and the air supply is used to meet the air distribution of the inner layer gas to ensure the stable combustion requirements of the burner. A plurality of gas spray holes are arranged at the end of the T-shaped or / and L-shaped spray gun of the outer layer gas gun, and the gas of the spray hole is sprayed at multiple angles perpendicular to the outlet cross section, and finally forms a counter-injection airflow structure with the rotating airflow formed at the outlet of the inner secondary air duct, so as to promote the rapid mixing and combustion requirements of the gas and air. The flame of the burner of the present invention can well adapt to the requirements of the furnace design, and the outer layer gas gun rotates the appropriate injection angle, so that the gas can be quickly and evenly mixed with the air after being sprayed out, and the temperature field in the furnace is uniform, thereby achieving efficient combustion and low nitrogen oxide emission requirements. Using pure air to assist combustion, nitrogen oxides can be less than 50mg / Nm without the production of carbon monoxide. 3 . BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 This is a schematic diagram of the structure of a low-nitrogen gas burner of the present invention;
[0018] Figure numerals: 1. Central primary air channel; 2. Inner secondary air channel; 3. Outer secondary air channel; 4. Wind box; 5. Central inner layer gas gun; 6. Gas collecting box; 7. Outer layer gas gun; 8. Nozzle; 9. Swirl blade. DETAILED DESCRIPTION
[0019] In order to make the present invention more clearly understood, a preferred embodiment is described in detail with reference to the accompanying drawings as follows:
[0020] like Figure 1 As shown, the present invention provides a low-nitrogen gas burner, including a gas channel, a combustion-supporting air channel and a wind box 4; the gas channel is provided with an inner and outer layer, and the gas channel is provided in the combustion-supporting air channel; a combustion-supporting air channel is provided between the inner and outer layers of the gas channel; the combustion-supporting air channel is connected to the wind box 4, and an air duct inlet is provided in the wind box 4. The combustion-supporting air channel includes a central primary air channel 1, an inner secondary air channel 2 and an outer secondary air channel 3; the central axes of the central primary air channel 1, the inner secondary air channel 2 and the outer secondary air channel 3 coincide. The inner layer gas channel of the gas channel is provided with a central inner layer gas gun 5; the central inner layer gas gun 5 is sleeved inside the central primary air channel 1. An inclined surface is provided at the end of the central inner layer gas gun 5 close to one end in the furnace, and an angle is provided between the inclined surface and the central axis of the central inner layer gas gun; and a jet hole is provided on the inclined surface. An inner secondary air channel 2 is provided on the outer periphery of the central primary air channel 1, and a swirl blade 9 is provided at the outlet of one end of the inner secondary air channel 2 close to the furnace. An outer secondary air channel 3 is provided on the periphery of the inner secondary air channel 2; an outer gas channel of the gas channel is provided in the outer secondary air channel 3. The outer gas channel is provided as an outer gas gun 7 connected to the gas collecting box 6; the end of the outer gas gun 7 close to the furnace is adjacent to the outlet of the inner secondary air channel 2 close to the furnace. A nozzle 8 of T-shaped or / and L-shaped structure is provided at the end of the outer gas gun 7 close to the furnace; a gas spray hole is provided on the nozzle 8. The central primary air channel 1 is provided as a direct current air channel, the inner secondary air channel 2 is provided as a swirl air channel, and the outer secondary air channel 3 is provided as a direct current air channel. The outer gas gun 7 is provided with a nozzle 8 which can form a counter-flow airflow with the swirl wind in the inner secondary air channel 2 and can rotate at any angle around the center axis of the outer gas gun itself. The present invention allows the gas and air to be evenly mixed and burned quickly at the nozzle, and avoids the occurrence of local high-temperature areas, and has low nitrogen oxide emission performance.
[0021] Example
[0022] like Figure 1A gas low-nitrogen burner is shown, comprising a gas channel, a combustion-supporting air channel and a wind box 4. The gas channel is arranged in two layers, inner and outer, and the combustion-supporting air channel is divided into a coaxial central primary air channel 1, an inner secondary air channel 2 and an outer secondary air channel 3. The air duct inlets are all arranged in the wind box 4. The inner layer gas is located at the center of the primary air channel 1, and the outer layer gas is arranged in the outer secondary air channel 3; the inner layer gas is sprayed into the furnace through the central inner layer gas gun 5, the inclined surface at the end of the spray gun forms a certain angle with the circumference, and 4-12 gas injection holes are evenly arranged on the inclined surface, and the inner layer gas accounts for 5-15% of the total gas; the outer layer gas is connected to a plurality of outer layer gas guns 7 through a gas collecting box 6, and the head of the spray gun is a T-shaped or / and L-shaped nozzle 8, and a plurality of gas injection holes are opened at the head of the nozzle 8. The number of spray guns and spray holes is determined according to the power of the burner. The number of outer gas guns 7 is generally 4-20, and the number of spray holes of a single gun is generally 4-10; the central primary air channel 1 is a DC air channel, the inner secondary air channel 2 is a swirl air channel, and the outer secondary air channel 3 is a DC air channel; a swirl blade 9 is arranged at the outlet of the inner secondary air channel 2; the nozzle 8 of the outer gas gun 7 can rotate at any angle around its own axis, and the gas from the outer spray hole is sprayed in the opposite direction of the inner secondary air swirl to form a counter-flow airflow with the swirl wind.
[0023] The present invention provides a novel low-nitrogen gas burner, which is a circular structure and includes: a central primary air channel 1, an inner secondary air channel 2, an outer secondary air channel 3, a wind box 4, a central inner layer gas gun 5, an outer layer gas gas collecting box 6 and an outer layer gas gun 7, a nozzle 8 with a T-shaped or / and L-shaped structure at the end of the outer layer gas gun, and an inner secondary air swirl blade 9. The gas channel is divided into two layers, and the combustion-supporting air channel is divided into three levels. The central inner layer gas is located in the central primary air channel 1, and the outer layer gas is located in the outer secondary air channel 3. The multi-level distribution of fuel and air and the multi-gun injection counter-flow structure enable the gas and air to be mixed evenly and burned quickly, while dispersing the fuel, so as to meet the purpose of controlling the combustion temperature and reducing the emission of nitrogen oxides. The central primary air channel 1 and the outer secondary air channel 3 are direct current air channels, the inner secondary air channel 2 is a swirl air channel, and the outlet of the inner secondary air channel 2 is arranged with swirl blades. The air supply of the central direct current channel of the central primary air channel 1 meets the initial air distribution requirements of the inner layer gas, ensuring the ignition and stable combustion of the center of the burner. A number of gas spray holes are arranged on the T-shaped or / and L-shaped nozzle 8 at the end of the outer gas gun. The gas from the spray holes can be sprayed at multiple angles perpendicular to the outlet cross section, and the outer gun is rotated to a suitable spray angle, and finally forms a counter-flow structure with the swirl wind at the outlet of the inner secondary air duct 2, so as to promote the rapid mixing and combustion of the gas and air and achieve the purpose of low nitrogen emissions.
[0024] The above is only a preferred embodiment of the present invention, and is not any formal or substantial limitation of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and supplements without departing from the present invention, and these improvements and supplements should also be regarded as the protection scope of the present invention. Any technician familiar with this profession, without departing from the spirit and scope of the present invention, can make some changes, modifications and equivalent changes made by using the technical content disclosed above, which are equivalent embodiments of the present invention; at the same time, any changes, modifications and evolutions of any equivalent changes made to the above embodiments based on the essential technology of the present invention are still within the scope of the technical solution of the present invention.
Claims
1. A low nitrogen gas burner, characterized in that: It includes a gas channel, a combustion-supporting air channel and a wind box; the gas channel is provided with an inner and outer layer, and the gas channel is provided in the combustion-supporting air channel; a combustion-supporting air channel is provided between the inner and outer layers of the gas channels; the combustion-supporting air channel is connected to the wind box, and an air duct inlet is provided in the wind box; The combustion-supporting air channel includes a central primary air channel, an inner secondary air channel and an outer secondary air channel; the central axes of the central primary air channel, the inner secondary air channel and the outer secondary air channel coincide with each other; The inner gas channel of the gas channel is provided with a central inner gas gun; the central inner gas gun is sleeved inside the central primary air channel; the end of the central inner gas gun close to one end in the furnace is provided with an inclined surface, and an angle is formed between the inclined surface and the central axis of the central inner gas gun; and an injection hole is provided on the inclined surface; An inner secondary air channel is arranged at the periphery of the central primary air channel, and a swirl blade is arranged at the outlet of one end of the inner secondary air channel close to the furnace; an outer secondary air channel is arranged at the periphery of the inner secondary air channel; an outer gas channel of the gas channel is arranged in the outer secondary air channel; the outer gas channel is arranged as an outer gas gun connected to the gas collecting box; one end of the outer gas gun close to the furnace is adjacent to the outlet of the inner secondary air channel close to one end of the furnace; The outer layer gas gun is provided with a T-shaped or / and L-shaped nozzle at one end close to the furnace; and a gas spray hole is provided on the nozzle.
2. A low nitrogen gas burner according to claim 1, characterized in that: The central primary air channel is set as a DC air channel, the inner secondary air channel is set as a swirl air channel, and the outer secondary air channel is set as a DC air channel.
3. A low nitrogen gas burner as claimed in claim 2, characterized in that: The outer gas gun is provided with a nozzle which can make the outer gas and the swirling wind in the inner secondary air channel form a counter-flow, and can rotate around the center axis of the outer gas gun at any angle.