CN213955298U

CN213955298U - Combustion cylinder for reducing nitrogen oxide

Info

Publication number: CN213955298U
Application number: CN202022903876.0U
Authority: CN
Inventors: 石瑞章; 郭永军; 苏嫄; 李贵利; 秦建党; 李战华; 王利刚
Original assignee: Hebi Baofa Energy Science & Technology Co ltd
Current assignee: Hebi Baofa Energy Science & Technology Co ltd
Priority date: 2020-12-07
Filing date: 2020-12-07
Publication date: 2021-08-13
Anticipated expiration: 2030-12-07

Abstract

The utility model provides a reduce nitrogen oxide's a combustion section of thick bamboo, including one-level fuel pipe, tuber pipe, secondary fuel pipe and flame tube, the tuber pipe sets up in the one-level fuel pipe outside, and the flame tube sets up in the tuber pipe outside, and the secondary fuel pipe sets up between tuber pipe and flame tube, is equipped with the main hole of going out a fire that corresponds with one-level fuel pipe and the secondary hole of going out a fire that corresponds with the secondary fuel pipe on the flame tube; and a graded fuel nozzle pipe fitting is arranged on the primary fuel pipe. The utility model discloses a send into the combustion cylinder with fuel from different regions for fuel divides the region to burn stage by stage, utilizes the space in the combustion cylinder to arrange fuel dispersion, realizes the hierarchical burning of fuel, reduces flame concentration, reduces the temperature of high temperature zone, makes the flue gas local circulation in the stove, forms reducing atmosphere, makes the NO that the part has produced be N2, thereby controls NOx's emission concentration on the total amount.

Description

Combustion cylinder for reducing nitrogen oxide

Technical Field

The utility model relates to a combustor technical field especially relates to a reduce nitrogen oxide's a burning section of thick bamboo.

Background

Nitrogen oxides, mainly NO and NO, produced during combustion of fuel_2，These two nitrogen oxides are commonly referred to as nitrogen oxides NO_X. Nitrogen oxide (NOx), which is harmful to human health, generates chemical smog through sunlight, oxynitride, ozone and the like through a series of physical and chemical reactions in the atmosphere, is also an important cause of acid rain formation, and is an important source of generating particulate matters (PM 2.5) on the surface of the atmosphere.

And (5) displaying the monitoring statistical result of the national fuel industrial boilers. The fuel boiler with the nitrogen oxide emission concentration less than or equal to 200mg/m is only 35% when the method exceeds 150mg/m for carrying out the year up to 43%. The emission reduction of the nitrogen oxides is far from national data. Therefore, the search for a rational low-nitrogen combustion technology has been a problem to be solved, and in particular, improvement of industrial boilers and combustion apparatuses is urgent.

The generation mechanism and type of nitrogen oxides (NOx), and the main NOx generated during the combustion of fuel are: fuel type, thermal type, and rapid type.

Among them, the thermal type: NOx is produced by the oxidation of N2 in air at high temperatures, with higher reaction temperatures giving higher NOx formation rates. Very little NOx is produced at flame temperatures below 1300 c and a multiple NOx increase occurs at temperatures above 1500 c. The higher the oxygen concentration, the greater the amount of NOx produced. The longer the residence time in the high temperature zone, the more NOx is produced.

Quick type: during the combustion process, carbon oxide compounds are decomposed at high temperature to generate CH free radicals, the CH free radicals react with N2 molecules in air to generate HCN and N, and the HCN and the N are further oxidized, wherein the reaction time is only 60 m/s. Quick type: the production of NOx is very rapid, typically less than 5%.

Fuel type: it refers to the nitrogen-containing compound in the fuel produced in the combustion process, and the bonding bond energy is small, and the nitrogen-containing compound is easily decomposed and oxidized into NOx in the combustion process.

When the low-nitrogen combustion technology is improved, the thermal NOx is mainly controlled, and according to the generation mechanism of the thermal NOx, the flame temperature is reduced, the flame peak temperature is mainly reduced, and the range of a flame high-temperature area is narrowed. The specific measures are as follows: fuel air staged combustion technology, flue gas recirculation technology (internal circulation and external circulation), full-premixing surface combustion technology, water-cooling combustion technology, low excess air residue and the like.

SUMMERY OF THE UTILITY MODEL

To foretell technical problem, the utility model provides a reduce a combustion section of thick bamboo of nitrogen oxide for solve the problem that the NOx emission of combustor is high among the prior art.

In order to achieve the above purpose, the technical solution of the present invention is realized as follows:

a combustion cylinder for reducing nitrogen oxides comprises a primary fuel pipe, an air pipe, a secondary fuel pipe and a flame tube, wherein the air pipe is arranged outside the primary fuel pipe; and a graded fuel nozzle pipe fitting matched with the main fire outlet hole is arranged on the primary fuel pipe.

Furthermore, a first fuel nozzle, a second fuel nozzle and a third fuel nozzle are arranged on the grading fuel nozzle pipe fitting.

Further, the graded fuel nozzle pipe fitting comprises a graded main pipe coaxially connected with the primary fuel pipe, a first nozzle extending in the radial direction is arranged on the graded main pipe, and the first fuel nozzle is arranged at the outer end of the first nozzle.

Further, the pipe fitting is spouted to the slope of being responsible for in grades, spout contained angle theta =0~90 degree between pipe fitting and the hierarchical main pipe axis, it is connected with the second nozzle perpendicularly to spout one side that is close to main fire outlet on the pipe fitting, and the second fuel spout sets up at second nozzle tip, the opposite side of spouting the pipe fitting is equipped with third fuel spout.

Furthermore, a smoke suction inlet is arranged on the flame tube.

Furthermore, a left flow guide piece and a right flow guide piece which are matched with the smoke suction inlet are arranged between the secondary fuel pipe and the flame tube, and the left flow guide piece and the right flow guide piece are respectively positioned on two sides of the smoke suction inlet.

Furthermore, a flow guide shrinkage cover matched with the graded fuel nozzle pipe fitting is arranged on the air pipe.

Furthermore, the flow guide shrinkage cover comprises a conical cylinder extending along the axial direction of the air pipe, the large end of the conical cylinder is connected with the air pipe, and the small end of the conical cylinder faces the main fire outlet.

Furthermore, one end of the secondary fuel pipe close to the secondary fire outlet is provided with a secondary nozzle, and the spraying direction of the secondary nozzle extends along the radial direction of the air pipe and faces to the axis of the air pipe.

Furthermore, be equipped with on the flame tube and surely fire the dish, main fire hole and secondary fire hole all set up on surely firing the dish.

The utility model has the advantages that: the utility model discloses a send into the combustion barrel with fuel from different regions for fuel divides the region by stage to burn, utilizes the space in the combustion barrel to arrange fuel dispersion, realizes the hierarchical burning of fuel, reduces flame concentration, reduces the temperature of high temperature zone, impels the flue gas local circulation in the stove, forms reducing atmosphere, makes partial NO that has produced be N2, thereby controls NOx's emission concentration in the total amount; the primary fuel supplied by the primary fuel pipe can be sprayed out in a dispersed mode through the graded fuel nozzle pipe fitting, the flame shape is enlarged, dispersed flames are formed, the flame concentration degree is further avoided, the temperature of the flame center is reduced, the fuel and air are fully mixed, the local high-temperature area is further avoided, and the emission concentration of NOx is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic structural view of the present invention;

fig. 2 is a sectional view of section a-a in fig. 1.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without any creative effort belong to the protection scope of the present invention.

As shown in fig. 1 and fig. 2, the combustion cylinder for reducing nitrogen oxides of the present invention comprises a primary fuel pipe 1, a wind pipe 2, a secondary fuel pipe 3 and a flame tube 4, wherein the wind pipe 2 is disposed outside the primary fuel pipe 1, the inlet end of the primary fuel pipe 1 is connected with a fuel source for inputting the primary fuel to the center of the combustion cylinder, the inlet end of the wind pipe 2 is connected with a fan for introducing air into the combustion cylinder, the flame tube 4 is disposed outside the wind pipe 2 as an outer shell, the secondary fuel pipes 3 are disposed in plural numbers, the plural secondary fuel pipes 3 are uniformly disposed between the wind pipe 2 and the flame tube 4 around the wind pipe 2, and the secondary fuel pipes 3 are connected with the flame tube 4, the inlet end of the secondary fuel pipe 3 is also connected with the fuel source for inputting the secondary fuel to the combustion cylinder by an outer ring; the middle part of the flame tube 4 is provided with a main fire outlet 7 corresponding to the primary fuel pipe 1, the main fire outlet 7 outputs central flame generated by primary fuel, the outer ring of the main fire outlet 7 on the flame tube 4 is provided with a secondary fire outlet 8 corresponding to the secondary fuel pipe 3, the outer ring flame generated by secondary fuel is output from the secondary fire outlet 8, fuel is sent into the combustion tube from different areas, so that the fuel is combusted in stages and areas, the fuel is dispersed and arranged by utilizing the space in the combustion tube, the staged combustion of the fuel is realized, the flame concentration is reduced, the temperature of a high-temperature area is reduced, the local circulation of smoke in the furnace is promoted, a reducing atmosphere is formed, part of generated NO is N2, and the emission concentration of NOx is controlled on the total amount; the primary fuel pipe 1 is provided with a graded fuel nozzle pipe fitting 6 matched with the main fire outlet 7, the graded fuel nozzle pipe fitting 6 enables primary fuel supplied by the primary fuel pipe 1 to be sprayed out in a dispersed mode, the shape of flame is enlarged, dispersed flame is formed, flame concentration is further avoided, the temperature of the flame center is reduced, the fuel and air are mixed fully, a local high-temperature area is further avoided, and the emission concentration of NOx is reduced.

Further, as shown in fig. 1 and fig. 2, the staged fuel nozzle pipe member 6 is provided with a first fuel nozzle 64, a second fuel nozzle 67 and a third fuel nozzle 63, and the primary fuel is sprayed out from three different nozzles to realize distributed flames.

Further, as shown in fig. 1 and 2, the staged fuel nozzle pipe member 6 includes a staged main pipe 61 coaxially connected to the primary fuel pipe 1, a radially extending first nozzle 62 is disposed at an end of the staged main pipe 61, and the first fuel nozzle 64 is disposed at an outer end of the first nozzle 62, so that the primary fuel is ejected toward a side wall of the air duct 2, and thus the fuel and the air can be premixed more, which is beneficial to sufficient mixing and avoids carbon monoxide exceeding the standard.

Further, as shown in fig. 1, a spraying pipe member 65 is obliquely arranged on the main grading pipe 61, the spraying pipe member 65 extends from the end of the main grading pipe 61 toward the main fire outlet 7 and is also oblique toward the side wall close to the air duct 2, the oblique angle is an included angle θ = 0-90 degrees between the spraying pipe member 65 and the axis of the main grading pipe 61, a second nozzle 66 is vertically connected to one side of the spraying pipe member 65 close to the main fire outlet 7, a second fuel nozzle 67 is arranged at the end of the second nozzle 66, and the other side of the spraying pipe member 65 is provided with the third fuel nozzle 63. The angle between the axis of the nozzle member 65 and the axis of the main staging pipe 61 is preferably θ = 15-70 degrees, and in this range, the second nozzle 66 is inclined toward the center of the main staging pipe 61 and toward the main fire outlet 7, so that the fuel of the second fuel nozzle 67 is ejected toward the center of the main staging pipe 61 and obliquely toward the main fire outlet 7, and a large contrast is formed with the fuel ejection direction of the first fuel nozzle 64, thereby enlarging the flame shape, and the third fuel nozzle 63 is disposed on the side of the nozzle member 65 away from the second fuel nozzle 67, and has a large contrast with the fuel ejection direction of the second fuel nozzle 67, thereby further enlarging the flame shape and avoiding the formation of a high temperature zone.

Further, as shown in fig. 1 and 2, a plurality of flue gas suction ports 5 are uniformly distributed on the side wall of the flame tube 4 in the circumferential direction. The flue gas can flow back into the flame tube 4 from the flue gas suction inlet 5, so that the oxygen concentration in the mixed gas is diluted, the combustion time of the fuel is prolonged, and the generation of a high-temperature area is avoided.

Further, as shown in fig. 1, further, as shown in fig. 1 and 2, a left flow guide 10 and a right flow guide 11 which are matched with the flue gas suction port 5 are arranged between the secondary fuel pipe 3 and the flame tube 4, and the left flow guide 10 and the right flow guide 11 are respectively located at two sides of the flue gas suction port 5. The left flow guide part 10 is of an annular structure, the cross section of the left flow guide part 10 is of a Z-shaped structure, one end of the Z-shaped structure is fixed with the inner wall of the flame tube 4, and the other end of the Z-shaped structure is fixed with the secondary fuel pipe 3; the right flow guide part 11 is also of an annular structure, the cross section of the right flow guide part 11 is of an inverted Z-shaped structure, one end of the inverted Z-shaped structure is fixed to the inner wall of the flame tube 4, and a gap is formed between the other end of the inverted Z-shaped structure and one end of the left flow guide part 10, which is fixed to the secondary fuel pipe 3, so that the backflow flue gas is guided to flow towards the fire outlet of the flame tube 4 through the gap.

Further, as shown in fig. 1, a flow guiding shrinkage hood 9 matched with the staged fuel nozzle pipe fitting 6 is arranged on the air pipe 2, and the flow guiding shrinkage hood 9 plays an accelerating role in the mixed primary fuel and air, so that a negative pressure lower than a certain value is formed in the flame tube 4. Under the action of negative pressure, the flue gas can flow into a flame area at the outlet of the flame tube 4 through the flue gas suction inlet 5, so that the oxygen concentration in the mixed gas is diluted, the combustion time of the fuel is prolonged, the combustion intensity is reduced, the generation of a high-temperature area is avoided, and the aim of reducing NOx emission is finally fulfilled. Moreover, through the structure, a circulating flue gas pipeline and a circulating fan are not required to be additionally arranged, so that the investment cost is low.

Further, as shown in fig. 1, the flow guiding shrinking casing 9 comprises a conical cylinder extending along the axial direction of the air duct 2, the large end of the conical cylinder is connected with the air duct 2, and the small end of the conical cylinder faces the main fire outlet 7, so as to play a flow guiding shrinking role on the mixed fuel and air.

Further, as shown in fig. 1, one end of the secondary fuel pipe 3 near the secondary fire outlet 8 is provided with a secondary nozzle 31, and the ejection direction of the secondary nozzle 31 extends along the radial direction of the air pipe 2 and faces the axis of the air pipe 2. In this embodiment, the end of the secondary fuel pipe 3 near the secondary fire outlet 8 is flush with the small end of the conical barrel, and the secondary nozzle 31 is disposed at the end of the secondary fuel pipe 3 and is ejected in the direction of the conical barrel, so that the secondary fuel and the air, i.e., the flue gas, have sufficient mixing time.

Further, as shown in fig. 1, the tip of the flame tube 4 is equipped with the circular shape and surely fires dish 41 and play the effect of surely firing, main fire outlet 7 and inferior fire outlet 8 all set up on surely firing dish 41, and main fire outlet 7 sets up in the middle part of surely firing dish 41, and inferior fire outlet 8 equipartition is around main fire outlet 7.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A combustion cylinder for reducing nitrogen oxides comprises a primary fuel pipe (1), an air pipe (2), a secondary fuel pipe (3) and a flame tube (4), and is characterized in that the air pipe (2) is arranged at the outer side of the primary fuel pipe (1), the flame tube (4) is arranged at the outer side of the air pipe (2), the secondary fuel pipe (3) is arranged between the air pipe (2) and the flame tube (4), and the flame tube (4) is respectively provided with a primary fire outlet (7) corresponding to the primary fuel pipe (1) and a secondary fire outlet (8) corresponding to the secondary fuel pipe (3); and a graded fuel nozzle pipe fitting (6) matched with the main fire outlet hole (7) is arranged on the primary fuel pipe (1).

2. The nox reducing burner cartridge of claim 1, wherein the staged fuel nozzle fitting (6) is provided with a first fuel nozzle (64), a second fuel nozzle (67) and a third fuel nozzle (63).

3. The nox reducing burner cartridge of claim 2, wherein the staged fuel nozzle fitting (6) includes a staged main tube (61) coaxially connected to the primary fuel tube (1), the staged main tube (61) being provided with a radially extending first nozzle (62), the first fuel nozzle (64) being disposed at an outer end of the first nozzle (62).

4. The combustion cylinder for reducing nitrogen oxides as claimed in claim 3, wherein the main grading pipe (61) is provided with an injection pipe member (65) in an inclined manner, the included angle θ = 0-90 degrees between the injection pipe member (65) and the axis of the main grading pipe (61), a second nozzle (66) is vertically connected to one side of the injection pipe member (65) close to the main fire outlet (7), the second fuel nozzle (67) is arranged at the end of the second nozzle (66), and the third fuel nozzle (63) is arranged on the other side of the injection pipe member (65).

5. The combustion cylinder for reducing nitrogen oxides according to any one of claims 1 to 4, wherein the flame tube (4) is provided with a flue gas suction inlet (5).

6. The combustion cylinder for reducing nitrogen oxides according to claim 5, wherein a left guide member (10) and a right guide member (11) which are matched with the flue gas suction inlet (5) are arranged between the secondary fuel pipe (3) and the flame tube (4), and the left guide member (10) and the right guide member (11) are respectively positioned at two sides of the flue gas suction inlet (5).

7. The combustion cylinder for reducing the nitrogen oxides according to any one of claims 1 to 4 and 6, wherein the air duct (2) is provided with a flow guiding shrinkage cover (9) matched with the staged fuel nozzle pipe fitting (6).

8. The nitrogen oxide reduction combustion can according to claim 7, characterized in that the flow guiding shrink hood (9) comprises a conical can extending axially along the flue pipe (2), the large end of the conical can being connected to the flue pipe (2) and the small end of the conical can facing the main fire hole (7).

9. The combustion cylinder for reducing nitrogen oxides as claimed in claim 1 or 8, wherein one end of the secondary fuel pipe (3) close to the secondary fire hole (8) is provided with a secondary nozzle (31), and the ejection direction of the secondary nozzle (31) extends along the radial direction of the air pipe (2) and faces the axis of the air pipe (2).

10. The combustion cylinder for reducing nitrogen oxides according to claim 9, wherein a combustion stabilizing disc (41) is arranged on the flame tube (4), and the main fire outlet (7) and the secondary fire outlet (8) are both arranged on the combustion stabilizing disc (41).