CN220269371U - Heating furnace burner - Google Patents

Abstract

The tube type heating furnace is widely applied to petrochemical industry, natural gas chemical industry and organic chemical industry, and is a continuous operation heating device for combustion. However, the tube heating furnace has extremely high working temperature and is easy to generate a large amount of nitrogen oxides, and the emission amount of the nitrogen oxides is an important technical index for measuring industry. The application provides a heating furnace burner, which ignites a pilot lamp through an ignition gun and then ignites the burner, so that the ignition mode is stable and the ignition success rate is high; the circulating flue gas pipeline is arranged, the flue gas is pumped back into the combustor through the flue gas circulating pipeline, the combustion reaction is carried out again, and the flue gas can reduce the oxygen concentration in the mixed gas during combustion, so that the temperature of flame during combustion is reduced, and the emission of NOx is reduced; the gas pipeline of the burner is divided into two stages, the wind channel is also divided into two stages, and a lean combustion area and a rich combustion area are correspondingly formed above the burner, and the two combustion modes can reduce the temperature during combustion, thereby reducing the emission of NOx.

Description

Heating furnace burner

Technical Field

The application relates to the technical field of petrochemical tubular heating furnaces, in particular to a heating furnace burner.

Background

The original tube type heating furnace is widely applied to petrochemical industry, natural gas chemical industry and organic chemical industry, and is a continuous operation heating device with combustion. The main advantages are high heating temperature, high heat transfer capability and convenient operation and management. The thermal efficiency of the heating furnace affects the safety and economy of the production operation of the device. And the technical transformation of the heating furnace and the daily management of the heating furnace are emphasized, and the improvement of the flue gas quality and the heat efficiency of the heating furnace is the key for meeting the requirements of environmental protection, reducing energy consumption and improving economic benefits. Through reforming transform the combustor, can reduce the emission of pollutant, the heating furnace flue gas nitrogen oxide content after reforming transform reaches the standard, but heating furnace thermal efficiency still has great promotion space.

In the first aspect, with the development of the combustion technology of the tubular furnace burner and the increasing environmental protection requirements, the requirements on the discharge index of the burner are more strict. The highest temperature of the tube heating furnace can reach 1500-1800 ℃, so that a large amount of nitrogen oxides are easy to generate. The new standard prescribes that the NOx emission index in the flue gas is required to be controlled below 50 mu L/L, and the low NOx emission value becomes an important technical index for measuring the burner products nowadays. The high NOx emission value not only pollutes the environment, but also the fuel is not fully combusted, resulting in waste of resources.

In the second aspect, as known by studying the mechanism and influencing factors of the formation of rapid NOx and thermal NOx in the fuel combustion process, the technologies for reducing nitrogen oxides mainly include low NOx combustion technology and flue gas denitration technology 2. The NOx emission concentration of the gas tube type heating furnace is generally maintained at 100-160 mg/Nm < 3 >, the gas tube type heating furnace is close to the emission standard limit value, and the low NOx combustion technology is mainly adopted to reduce the generation of NOx at present because the flue gas denitration technology has the problems of large investment, high operation cost and the like. In order to meet the increasingly strict environmental protection requirements, low NOx combustors are continuously developed in technology, and the generation amount of NOx in the combustion process is reduced mainly through combustion technologies such as air classification, fuel classification, flue gas recirculation and the like. The main purpose of the three technologies is to reduce the temperature of the flame area, avoid the existence of local high temperature area of the flame and reduce thermal NOx. The lower the flame zone temperature, the lower the thermal NOx production. However, as the temperature of the flame area is reduced, the stability of flame combustion is reduced, and potential safety hazards such as flame failure and flameout are very easy to occur.

Disclosure of Invention

The application provides a heating furnace burner, which solves the problems of high NOx emission of the heating furnace and unstable combustion flame of the burner, and improves the combustion efficiency and the combustion stability;

in order to achieve the technical effects, the application adopts the following technical scheme:

a burner for a heating furnace, comprising: the device comprises a pilot burner, a primary gas pipeline, a primary gas nozzle, a secondary gas pipeline, a secondary gas nozzle, a smoke circulation pipeline, a circulating smoke nozzle, a wind baffle plate and a cyclone;

the pilot burner is positioned at the center of the burner, the cyclone is arranged outside the pilot burner, and the primary gas nozzle is arranged at the center of the cyclone; the primary gas spray nozzle is arranged on the inner side of the air baffle plate, and the secondary gas spray nozzle is arranged on the outer side of the air baffle plate; the primary gas nozzle is connected with a primary gas pipeline, and the secondary gas nozzle is connected with a secondary gas pipeline; a primary air channel is formed in a gap between the air baffle plate and the primary gas nozzle, and a secondary air channel is formed in a gap between the air baffle plate and the secondary gas nozzle;

the smoke circulating pipeline is arranged between the primary gas pipeline and the secondary gas pipeline, and the circulating smoke nozzle is formed by opening above the smoke circulating pipeline.

Specifically, the primary gas pipeline and the primary gas nozzle are respectively provided with 4, and the secondary gas pipeline and the secondary gas nozzle are respectively provided with 18.

Specifically, the pilot burner is arranged at the position 140mm below the burner, and the pilot burner is provided with a flame stabilizing cap as a flame stabilizing device, so that the pilot burner is prevented from being influenced by fluctuation of an upstream system and surrounding environment, and flame can be stably combusted upwards for a long time; after the burner has faults such as combustion deviation or extinction caused by external influence, the pilot burner can be ignited for the second time, so that the stable operation of the boiler system is ensured.

Specifically, the main burner further comprises a smoke circulating pipeline and a circulating smoke nozzle; when the fuel reacts with air, a large amount of smoke is generated, part of the smoke is pumped back into the burner through the smoke circulating pipeline and sprayed out from the circulating smoke nozzle, and the combustion reaction is carried out again, so that the temperature of flame during combustion is reduced, and the emission of NOx is reduced.

Specifically, the heating furnace burner is provided with the swirler, through multiple rotational flow modes, the rotational flow intensity of fuel gas is enhanced, the mixing speed and the mixing degree of the fuel gas and combustion air are increased, the flame length after combustion is reasonable, no flame is removed, no backfire is generated, and the combustion is more sufficient.

Specifically, the burner adopts an external mixing type porous jet type structure, the combustion is sufficient, and the space temperature field and the speed field in the hearth are distributed reasonably, so that the temperature distribution requirement in the furnace is met, and meanwhile, the emission of nitrogen oxides meets the low-nitrogen requirement.

Specifically, the gap between the air baffle plate and the primary fuel gas nozzle is a primary air channel, and the gap between the air baffle plate and the secondary fuel gas nozzle is a secondary air channel. The fuel gas can be fully combusted in the shortest time, and local high temperature is not generated, so that the emission of NOx is reduced.

Specifically, the bottom of the heating furnace burner is provided with an air door baffle, the right side of the heating furnace burner is provided with an air ring baffle, and the air door baffle and the air ring baffle are used for adjusting the air flow entering the furnace.

Specifically, the burner is provided with a high-energy igniter; the high energy igniter includes: an ignition gun (19), an explosion-proof junction box, an embedded system and a high-voltage cable; the embedded system consists of a PLC, so that ignition can be automatically controlled, and high energy and high ignition success rate can be realized.

Specifically, the ignition mode adopts a three-stage ignition mode: igniting gun, igniting pilot lamp and burner; the ignition gun is fixed at the position right above the pilot burner, the hearth is a micro negative pressure environment, air distribution is natural air suction, the ignition gun ignites the pilot burner, the pilot burner ignites the burner, and whether the pilot burner ignites is judged through a flame detector arranged on the burner.

Compared with the prior art, the heating furnace burner provided by the application has the following beneficial technical effects:

(1) The heating furnace burner provided by the application adopts an external mixing type porous jet structure, so that the combustion is fully and efficiently performed, and the space temperature field and the speed field in the hearth are distributed reasonably, thereby meeting the temperature distribution requirement in the furnace;

(2) The burner can pump part of the flue gas back into the burner through the flue gas circulation pipeline, and the flue gas is sprayed out from the circulating flue gas nozzle to perform combustion reaction again, so that the temperature of flame during combustion is reduced, the emission of NOx is reduced, and the low-nitrogen requirement of nitrogen oxide emission is met;

(3) When the gas burner is actually used, flame combustion is stable, tempering and flame removal are avoided, the head is not ablated, and the burning area is overheated and overtemperature and the like are avoided;

(4) The burner head is designed with a flame stabilizing device, the flame length is reasonable and stable, and the flame is ensured not to directly contact the heat exchange tube materials and other burners in the furnace;

(5) The ignition and operation adjustment are convenient, safe and reliable.

In addition to the technical problems, features constituting the technical solutions, and advantageous effects brought about by the technical features of the technical solutions described above, other technical problems that can be solved, other technical features included in the technical solutions, and advantageous effects brought about by the technical features are provided in the present application, and further detailed description will be made in the detailed description of the present application.

Drawings

The accompanying drawings are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate the application and together with the embodiments of the application, and not constitute a limitation to the application.

FIG. 1 is a schematic diagram showing a cross-sectional elevation structure of a burner of a heating furnace;

fig. 2 is a top view of a burner of a heating furnace.

Reference numerals:

1. an air inlet flange; 2. a flue gas circulation duct; 3. a secondary gas pipeline; 4. a secondary gas nozzle; 5. a circulating smoke nozzle; 6. a cyclone; 7. a primary gas pipeline; 8. a primary gas nozzle; 9. a firing cap; 10. a wind shielding plate; 11. a wind ring baffle; 12. a baffle; 13. a gas loop; 14. a gas connection pipe; 15. a gas port flange; 16. a bottom plate; 17. flame detector jacks; 18. gas plug of the pilot lamp; 19. igniting the gun; 20. a pilot lamp; 21. an ignition gun socket; 22. and a damper baffle.

Detailed Description

In order to make the above objects, features and advantages of the present application more comprehensible, the following description will make clear and complete description of the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. All other embodiments, based on the embodiments herein, which are within the scope of the protection of the present application, will be within the purview of one of ordinary skill in the art without the exercise of inventive faculty.

As shown in fig. 1-2, an embodiment of the present application provides a burner for a heating furnace, including: the burner comprises a pilot burner 20, a primary gas pipeline 7, a primary gas nozzle 8, a secondary gas pipeline 3, a secondary gas nozzle 4, a flue gas circulation pipeline 2, a circulating flue gas nozzle 5, an air baffle 10 and a cyclone 6;

the pilot burner 20 is positioned at the center of the burner, the pilot burner 20 is externally provided with the cyclone 6, the center of the cyclone 6 is provided with the primary gas spray head 8, the primary gas spray head 8 is arranged at the inner side of the air baffle 10, and the secondary gas spray head 4 is arranged at the outer side of the air baffle 10; the primary gas nozzle 8 is connected with the primary gas pipeline 7, and the secondary gas nozzle 4 is connected with the secondary gas pipeline 3; a primary air channel is formed in a gap between the air baffle plate 10 and the primary gas spray head 8, and a secondary air channel is formed in a gap between the air baffle plate 10 and the secondary gas spray head 4;

the heating furnace burner is provided with a smoke circulating pipeline 2 and a circulating smoke nozzle 5; the flue gas circulation pipeline 2 is arranged between the primary gas pipeline 7 and the secondary gas pipeline 3, and the circulating flue gas nozzle 5 is formed by opening above the flue gas circulation pipeline 2, as shown in fig. 1.

As an example of implementation, the primary gas pipe 7 and the primary gas shower head 8 are each provided with 4, and the secondary gas pipe 3 and the secondary gas shower head 4 are each provided with 18, as shown in fig. 2.

As an example of implementation, the pilot burner is arranged at the position 140mm below the main burner, and by providing the flame stabilizing device with the flame cap 9, the pilot burner 20 can be ensured not to be influenced by external fluctuation and surrounding environment, and can burn stably for a long time; after the burner has failed, such as deviated combustion or extinction, due to external influence, the pilot lamp 20 can be ignited again, so that the stable operation of the boiler system is ensured, as shown in fig. 1.

As an example of implementation, the main burner further comprises a flue gas recirculation duct 2 and a recirculation flue gas spout 5. When the fuel reacts with air, a large amount of smoke is generated, part of the smoke is pumped back into the burner through the smoke circulation pipeline 2 and sprayed out from the circulating smoke nozzle 5 to perform a combustion reaction again, the smoke can reduce the oxygen concentration in the mixed gas during combustion, and the smoke acts as a heat absorber, so that the combustion temperature is not too high, the temperature of flame during combustion is reduced, the generation of nitrogen oxides is inhibited, and the emission of NOx is reduced.

As an example, the heating furnace burner is provided with the cyclone 6, the cyclone strength of the fuel gas is enhanced by various cyclone modes, the mixing speed and the mixing degree of the fuel gas and the combustion air are increased, the flame length after combustion is reasonable, no fire is removed, no backfire is generated, and the combustion is more sufficient.

As an implementation example, the burner adopts an external mixing type porous jet type structure, the combustion is sufficient, and the space temperature field and the speed field in the hearth are distributed reasonably, so that the temperature distribution requirement in the furnace is met, and meanwhile, the emission of nitrogen oxides meets the low-nitrogen requirement.

As an example, the gap between the air barrier 10 and the primary gas nozzle 8 is a primary air passage, and the gap between the air barrier 10 and the secondary gas nozzle 4 is a secondary air passage. The fuel gas can be fully combusted in the shortest time, and local high temperature is not generated, so that the emission of NOx is reduced.

As an example of implementation, a damper baffle 22 is provided at the bottom of the burner of the heating furnace, and a wind ring baffle 11 is provided at the right side, and the damper baffle 22 and the wind ring baffle 11 function to adjust the amount of air flow into the furnace.

As one practical example, the burner is provided with a high-energy igniter; the high energy igniter includes: ignition gun 19, explosion-proof junction box, embedded system, high voltage cable; the embedded system consists of a PLC, so that ignition can be automatically controlled, and high energy and high ignition success rate can be realized.

As one practical example, the ignition mode adopts a three-stage ignition mode: igniting gun 19-igniting pilot lamp 20-igniting burner; the ignition gun 19 is fixed at a position right above the pilot burner 20, the hearth is in a micro negative pressure environment, air distribution is natural air suction, the ignition gun 19 firstly ignites the pilot burner 20, the pilot burner 20 ignites the burner, and whether the pilot burner ignites or not is judged through a flame detector arranged on the burner.

As an example, an air inlet flange 1 is provided at the port of the flue gas circulation pipeline 2, and when the fuel and air react, a great amount of flue gas is generated, and a part of the flue gas is pumped into the flue gas circulation pipeline through the air inlet and then pumped into the burner.

As an implementation example, a gas connection pipe 14 is arranged at the right lower corner of the burner, the gas connection pipe 14 is connected into the burner to be connected with a gas ring pipe 13, and a primary gas pipeline 7 and a secondary gas pipeline 3 are sequentially connected to the gas ring pipe 13; the gas nipple 14 is provided with a gas port flange 15 at the port.

As one practical example, the lowermost end of the pilot burner is provided with a pilot burner gas plug 18 for delivering gas to the pilot burner.

As an example of implementation, the burner lower bottom plate 16 is provided with flame detector jacks 17 for connecting flame detectors; a burning torch socket 21 is provided just below the burner for connecting the burning torch.

The working principle of the heating furnace burner is as follows:

the fuel enters the burner from the gas connecting pipe 14, flows into the gas ring pipe 13, and is ejected from the primary gas nozzle 8 and the secondary gas nozzle 4 respectively through the primary gas pipeline 7 and the secondary gas pipeline 3. At the same time, air enters the combustion furnace from the air door baffle 22 and the air ring baffle 11, and flows out from the primary air channel and the secondary air channel, so that the mixing speed and the mixing degree of combustion air and fuel gas flowing out under the action of the swirler 6 can be increased. The ignition gun 19 firstly ignites the pilot burner 20, the pilot burner 20 ignites the fuel and air mixture sprayed out of the burner, and the cyclone 6 can strengthen the cyclone strength of the fuel and the air, so that the flame length after combustion is reasonable, the flame is not removed from fire, tempering is not carried out, and the combustion is more sufficient. When the fuel reacts with air, a large amount of smoke is generated, part of the smoke is pumped back into the burner through the smoke circulation pipeline 2 and sprayed out from the circulating smoke nozzle 5 to perform a combustion reaction again, the smoke can reduce the oxygen concentration in the mixed gas during combustion, and the smoke acts as a heat absorber, so that the combustion temperature is not too high, the temperature of flame during combustion is reduced, the generation of nitrogen oxides is inhibited, and the emission of NOx is reduced.

The pilot lamp 20 ignites the fuel and air in the primary gas pipeline 7 of the burner, the combustion zone is a primary combustion zone, the fuel is less and the air is more during combustion, and the combustion zone is a lean combustion zone; the secondary gas pipeline 3 burns fuel and air, which is a secondary combustion zone, and the secondary gas pipeline is rich in fuel and low in air excess coefficient, which is a rich combustion zone. The lean combustion area has less fuel and more air, and the air can reduce the flame temperature; the fuel in the rich region is more, the air is less, the fuel cannot be completely combusted at one time, and only partial combustion is insufficient, so that the combustion temperature can be lowered. The lean combustion zone and the rich combustion zone can reduce the temperature of flame during combustion and NO _x Is arranged in the air.

The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (9)

1. A burner for a heating furnace, comprising: the device comprises a pilot burner (20), a primary gas pipeline (7), a primary gas nozzle (8), a secondary gas pipeline (3), a secondary gas nozzle (4), a flue gas circulation pipeline (2), a circulating flue gas nozzle (5), an air baffle plate (10) and a cyclone (6);

the pilot burner (20) is positioned at the center of the burner, the pilot burner (20) is externally provided with the cyclone (6), and the center of the cyclone is the primary gas nozzle (8); the primary gas spray head (8) is arranged on the inner side of the air baffle plate (10), and the secondary gas spray head (4) is arranged on the outer side of the air baffle plate (10); the primary gas spray head (8) is connected with a primary gas pipeline (7), and the secondary gas spray head (4) is connected with a secondary gas pipeline (3); a primary air channel is formed in a gap between the air separation plate (10) and the primary gas nozzle (8), and a secondary air channel is formed in a gap between the air separation plate (10) and the secondary gas nozzle (4);

the flue gas circulation pipeline (2) is arranged between the primary gas pipeline (7) and the secondary gas pipeline (3), and the circulating flue gas nozzle (5) is formed by opening above the flue gas circulation pipeline (2).

2. A furnace burner according to claim 1, characterized in that the primary gas duct (7) and the primary gas burner (8) are each provided with 4, and the secondary gas duct (3) and the secondary gas burner (4) are each provided with 18.

3. Furnace burner according to claim 1, characterized in that there are 4 cyclones, each cyclone (6) being centrally provided with the primary gas burner (8).

4. The furnace burner of claim 1 wherein the furnace burner structure employs an external mix porous jet structure.

5. Furnace burner according to claim 1, characterized in that a flame stabilizing device is provided with a flame cap (9) on the pilot burner (20).

6. The heating furnace burner according to claim 1, characterized in that a damper baffle (22) is provided at the bottom of the heating furnace burner, and a wind ring baffle (11) is provided at the right side; the damper baffle (22) and the wind ring baffle (11) are used for adjusting the air flow into the furnace.

7. The burner of claim 1, further comprising a high energy igniter; the high energy igniter includes: an ignition gun (19), an explosion-proof junction box, an embedded system and a high-voltage cable.

8. The furnace burner of claim 7, wherein the in-line system is comprised of a PLC.

9. Furnace burner according to claim 1, characterized in that an ignition gun (19) is fixed in position directly above the pilot lamp (20).