CN212108382U - Multi-nozzle air distribution low-nitrogen combustor - Google Patents

Multi-nozzle air distribution low-nitrogen combustor Download PDF

Info

Publication number
CN212108382U
CN212108382U CN202020301948.1U CN202020301948U CN212108382U CN 212108382 U CN212108382 U CN 212108382U CN 202020301948 U CN202020301948 U CN 202020301948U CN 212108382 U CN212108382 U CN 212108382U
Authority
CN
China
Prior art keywords
gas
combustion
nozzle
burner
supporting air
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202020301948.1U
Other languages
Chinese (zh)
Inventor
梁龙
雍占锋
常春梅
贾刚建
邱康萍
张举乐
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
XUZHOU COMBUSTION CONTROL RESEARCH INSTITUTE CO LTD
Original Assignee
XUZHOU COMBUSTION CONTROL RESEARCH INSTITUTE CO LTD
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by XUZHOU COMBUSTION CONTROL RESEARCH INSTITUTE CO LTD filed Critical XUZHOU COMBUSTION CONTROL RESEARCH INSTITUTE CO LTD
Priority to CN202020301948.1U priority Critical patent/CN212108382U/en
Application granted granted Critical
Publication of CN212108382U publication Critical patent/CN212108382U/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Abstract

The utility model discloses a low NOx burner of multi-nozzle air distribution, 1% ~ 7% gas pass through the nozzle tangential and spout and form the flame on duty on the central burner block, 10% ~ 30% gas advance combustion-supporting wind advance between 100 ~ 500mm before furnace in advance mix in advance and form rarefied premixed gas and spout furnace, about 70% ~ 90% gas spout furnace through 5 ~ 25 gas spray guns. Most of the combustion-supporting air is divided into 5-25 parts and is sprayed into the hearth through the contraction-shaped nozzles, and the direction of the contraction-shaped nozzles stretching into the hearth is vector, so that the combustion-supporting air is enabled to be divided into 5-25 partsPossessing axial velocity, tangential velocity and radial velocity. The utility model discloses flame stabilization even do not use the flue gas extrinsic cycle, also can control NOx emission at 20mg/Nm during the burning natural gas3Left and right.

Description

Multi-nozzle air distribution low-nitrogen combustor
Technical Field
The utility model relates to a low NOx burner technical field especially relates to a low NOx burner of multiinjector air distribution.
Background
With the continuous and steady development of economy in recent years, environmental problems are receiving more and more attention. With the increasing prominence of environmental issues, the requirements of national and local governments on pollutant emissions will become more stringent. The requirement for NOx emission concentration of gas-fired boilers is gradually from 50mg/Nm3Down to 30mg/Nm3. The research and development of the gas low-nitrogen burner which meets the national conditions of China is urgent. Unlike pulverized coal burners, the nitrogen oxides produced by gas burners are mainly of the thermal type NOx. Therefore, considering the generation mechanism of NOx, the gas burner should reasonably organize the mixing process of gas and combustion air, so as to avoid the occurrence of a local high-temperature area in the furnace and reduce the average temperature of flame in the furnace. Meanwhile, the convection heat exchange quantity and the radiation heat exchange quantity of the flame are enhanced. At present, the main means for reducing NOx are staged combustion, dense-dilute combustion, premixed combustion, flue gas recirculation and the like. The flue gas external circulation technology can effectively reduce the emission value of NOx, and is also the most common method for most equipment manufacturers. But the boiler efficiency is reduced, the gas consumption is increased, the boiler vibrates, the steam in the flue gas corrodes in a combustor, the flame is unstable, the boiler output is reduced and the like after the flue gas is added for external circulation. Therefore, further reduction of NOx emissions without the use of flue gas recirculation is a challenge that technicians are required to overcome.
SUMMERY OF THE UTILITY MODEL
The technical problem is as follows: in order to overcome the weak point that exists among the prior art, the utility model provides a low NOx burner of multiinjector air distribution can reduce the nitrogen oxide that the gas produced when burning under the condition that does not use the flue gas extrinsic cycle, reaches energy-concerving and environment-protective requirement.
The technical scheme is as follows: a multi-nozzle air distribution low-nitrogen burner comprises a burner shell, wherein a combustion-supporting air inlet and a combustion-supporting air nozzle are arranged on the burner shell, and the combustion-supporting air nozzle is a plurality of small nozzles; a main gas chamber, an on-duty gas chamber and a central air duct are arranged in the combustor shell; the main gas chamber is provided with a main gas inlet pipe and a plurality of main gas guns, the main gas guns are provided with a plurality of premixed gas jet holes at the inner side of a combustion-supporting air nozzle, and the outlets of the main gas guns are provided with main gas gun heads; the on-duty gas chamber is provided with an on-duty gas inlet pipe and a plurality of on-duty gas guns; the outlet of the central wind cylinder is provided with a rotational flow combustion stabilizing cover, and the part of the central wind cylinder in the combustor shell is provided with a plurality of air inlets.
Furthermore, the combustion-supporting air nozzles are 5-25 small nozzles distributed on the same reference circle, the outlets of the combustion-supporting air nozzles are contraction-shaped nozzles, the contraction angle is 20-45 degrees, and the optimal contraction angle is 22-33 degrees.
Furthermore, the direction of the combustion-supporting air nozzle extending into the hearth is a vector, so that the combustion-supporting air has axial speed, tangential speed and radial speed; an included angle alpha between the outer expansion of the combustion-supporting air nozzle and the central shaft of the combustor is 10-30 degrees; the rotation angle beta of the combustion-supporting air nozzle relative to the central shaft of the inlet of the combustion-supporting air nozzle is 15-45 degrees.
Furthermore, a plurality of premixed gas jet holes are formed in the position, which is 100-500 mm away from the position where combustion-supporting air enters a hearth interface, of the main gas gun, part of gas is jetted into a combustor shell as premixed gas, and is mixed with the combustion-supporting air and then is fed into the hearth; the premixed gas amount is 10-30% of the total gas amount, and the gas concentration after the premixed gas and the combustion-supporting air are mixed is below the lower explosion limit.
Furthermore, the tail end of the gas gun on duty is provided with a plurality of gas jet holes for gas on duty; after 1% -7% of gas is sprayed out through the gas jet holes on duty, a part of the gas is tangentially sprayed onto the burner block to heat the burner block and stabilize flame for combustion, and a part of the gas is sprayed outwards to the periphery of the burner, so that the diameter of the flame on duty is increased, the length of the flame on duty is shortened, the heat exchange in the furnace at the outlet of the burner is enhanced, and the average temperature of the flame is reduced.
Furthermore, a part of the central air duct is arranged in the combustor shell, and a part of the central air duct extends out of the combustor shell; the part of the central wind cylinder in the combustor shell is provided with a plurality of air inlets, 5% -30% of combustion-supporting air enters the central wind cylinder from the air inlets, the central air is changed into rotational flow air from direct current air through the rotational flow combustion stabilizing cover and then is sent into a hearth, and the mixing between the combustion-supporting air and fuel gas is enhanced; the outside of the part of the central wind barrel extending out of the burner shell is sleeved with a burner block for stable combustion.
Furthermore, the tail end of the main gas gun head is provided with a plurality of main gas jet holes, so that the main gas can be combusted in a small range in a grading manner, and the included angle between the main gas jet holes and the central axis of the combustor is different from 0 degree to 30 degrees.
Has the advantages that: the utility model discloses a multi-nozzle air distribution low-nitrogen combustor has introduced the notion that the part mixes in advance, sprays 10% -30% gas in advance in the combustion-supporting wind and send into furnace after with the combustion-supporting wind intensive mixing, and the excess air coefficient when this part gas combustion is great, and gas and combustion-supporting wind mix gas concentration under the explosion lower limit, can not form visible flame, and slow oxidation has reduced the oxygen content in the flue gas when high temperature.
The utility model discloses creative hierarchical delivery with combustion-supporting wind changes the form of arranging a plurality of little nozzles around combustor a week into by the cyclic annular hierarchical delivery of prior art, and the quantity of little spout is 5-25, little spout can realize becoming the export sectional area to reach and improve combustion-supporting wind speed when the low-load, strengthen the mixing of combustion-supporting wind and gas.
The gas and the combustion-supporting air respectively form jet entrainment to the flue gas through the ingenious design of the positions of the gas spray gun and the combustion-supporting air nozzle, so that high-temperature low-oxygen combustion is realized.
The utility model discloses a multiinjector air distribution low NOx burner through above means, produced nitrogen oxide of effectual reduction gas when burning under the condition that does not use the flue gas extrinsic cycle technique. Compared with the existing gas low-nitrogen burner in the market, the burner not only eliminates the adverse factors caused by the external circulation of the flue gas, but also realizes the ultra-low emission of nitrogen oxides. Have wide applicability in the field.
Drawings
FIG. 1 is a cross-sectional view of an example of a multi-nozzle air-distribution low-nitrogen combustor in accordance with the present invention;
FIG. 2 is a right side view of FIG. 1;
FIG. 3 is an enlarged schematic view of FIG. 1 at A;
FIG. 4 is a schematic structural view of the outlet of the gas gun on duty of the present invention;
FIG. 5 is a schematic structural view of a main gas burner head;
wherein: the burner comprises a burner shell, 2 combustion-supporting air inlets, 3 on-duty gas inlet pipes, 4 main gas inlet pipes, 5 combustion-supporting air nozzles, 501 elbow parts, 502 necking parts, 6 burner blocks, 7 on-duty gas chambers, 8 main gas chambers, 9 central air ducts, 901 air inlets, 10 cyclone stable combustion covers, 11 on-duty gas guns, 1101 on-duty gas jet holes, 12 main gas guns, 1200 pre-mixed gas jet holes, 13 main gas gun heads and 1300 main gas jet holes.
Detailed Description
The invention will be further described with reference to an embodiment shown in the drawings.
As shown in fig. 1, the multi-nozzle air distribution low-nitrogen burner comprises a burner shell 1, a combustion-supporting air inlet 2, an on-duty gas inlet pipe 3, a main gas inlet pipe 4, a combustion-supporting air nozzle 5, a burner block 6, an on-duty gas chamber 7, a main gas chamber 8 and a central air duct 9, wherein the on-duty gas chamber 7, the main gas chamber 8 and the central air duct 9 are arranged in the burner shell 1; a rotational flow combustion stabilizing cover 10 is arranged in the outlet of the central wind barrel 9; the duty gas chamber 7, the main gas chamber 8 and the central wind barrel 9 are arranged along the central line of the burner; the on-duty gas chamber 7 leads the on-duty gas to the outer side of the burner shell 1 for combustion through a plurality of on-duty gas guns 11 arranged in the burner shell; the main gas chamber 8 guides the main gas to the outer side of the burner shell 1 through a plurality of main gas guns 12 arranged in the burner shell 1, and the main gas is divided by main gas gun heads 13 and then injected into a hearth for combustion.
As shown in fig. 1, the combustion-supporting air is divided into two stages, namely, central air and combustion-supporting air, so that the preliminary graded distribution of the combustion-supporting air is realized; the central wind barrel 9 is provided with a plurality of air inlets 901 at the inner part of the burner shell 1, 5% -30% of combustion-supporting air enters the central wind barrel 9 from the air inlets 901, the central air is changed into rotational flow air from direct flow air through the rotational flow combustion stabilizing cover 10 and then is sent into a hearth, and the mixing of the combustion-supporting air and fuel gas is enhanced.
As shown in fig. 1 and 2, the combustion-supporting air nozzles 5 are 5 to 25 small nozzles distributed on the same reference circle, so that further graded distribution of combustion-supporting air is realized, and the effect of reducing NOx is achieved; the outlet of the combustion-supporting air nozzle 5 is a contraction nozzle, so that the air speed of the combustion-supporting air is improved, and the mixing of the fuel gas and the air is more uniform; the direction of the combustion-supporting air nozzle 5 extending into the hearth is a vector, so that the combustion-supporting air has axial speed, tangential speed and radial speed; an included angle between the outer expansion of the combustion-supporting air nozzle and a central shaft of the combustor is 10-30 degrees, preferably 15 degrees, so that flame is hollowed, a high-temperature region of the flame is led away from the axis of the combustor, the peak temperature of the flame is reduced, and the generation of NOx is reduced; the contact between the combustion-supporting air and the secondary fuel gas is delayed through the design of the included angle, so that the combustion-supporting air and the fuel gas can be fully mixed with the flue gas, and the effect of enhancing the internal circulation of the flue gas is achieved; the combustion-supporting air nozzle 5 rotates 15-45 degrees relative to the central shaft of the inlet of the combustion-supporting air nozzle, so that the combustion-supporting air integrally generates rotational flow.
The combustion-supporting air nozzles 5 are welded on the outlet panel of the burner, and combustion-supporting air is uniformly distributed to a plurality of combustion-supporting open nozzles 5 to be sprayed into a hearth through the combustion-supporting air inlet and the burner shell.
As shown in fig. 1 and 3, the fuel gas is divided into three stages, namely, premixed fuel gas, duty fuel gas and main fuel gas, so that fuel can be effectively distributed in a grading manner; the main gas gun 12 is provided with a plurality of premixed gas jet holes 1200 within 100-500 mm before the combustion-supporting air enters the hearth interface, part of gas is used as premixed gas to be jetted into the burner shell 1, and the premixed gas is mixed with the combustion-supporting air and then is fed into the hearth; the premixed gas amount is 10-30% of the total gas amount, and the gas concentration after the premixed gas and the combustion-supporting air are mixed is below the lower limit of the explosion range; the excess air coefficient of the part of fuel gas is large during combustion, visible flame cannot be formed, the fuel gas is slowly oxidized at high temperature, and the oxygen content in the flue gas is reduced.
As shown in fig. 1 and 4, the tail end of the on-duty gas gun 11 is provided with a plurality of on-duty gas injection holes 1101; after 1% -7% of the gas is sprayed out through the gas spraying holes 1101 on duty, a part of the gas is tangentially sprayed to the burner block 6 to stabilize flame combustion, and a part of the gas is sprayed to the periphery of the burner, so that the diameter of the flame on duty is increased, the length of the flame on duty is shortened, the heat exchange in the furnace at the outlet of the burner is enhanced, and the average temperature of the flame is reduced; the combustor does not provide independent air distribution for on-duty gas, low-speed low-oxygen combustion is carried out by means of residual oxygen in backflow smoke, and generation of NOx is further reduced.
As shown in fig. 5, the end of the main gas burner head 13 is provided with a main gas jet hole 1300, so that the main gas can be combusted in a small range in a staged manner, and the generation of NOx is further reduced.
The embodiment of the present invention discloses a preferred embodiment, but not limited thereto, and those skilled in the art can easily understand the spirit of the present invention according to the above embodiment, and make different extensions and changes, but do not depart from the spirit of the present invention, all of which are within the protection scope of the present invention.

Claims (7)

1. A multi-nozzle air distribution low-nitrogen combustor is characterized by comprising a combustor shell (1), wherein a combustion-supporting air inlet (2) and a combustion-supporting air nozzle (5) are formed in the combustor shell (1); a main gas chamber (8), a duty gas chamber (7) and a central wind barrel (9) are arranged in the burner shell (1); a main gas inlet pipe (4) and a plurality of main gas guns (12) are arranged on the main gas chamber (8), a plurality of premixed gas jet holes (1200) are formed in the main gas guns (12) in front of a combustion-supporting air nozzle in the combustor shell (1), and main gas gun heads (13) are arranged at the outlets of the main gas guns (12); the on-duty gas chamber (7) is provided with an on-duty gas inlet pipe (3) and a plurality of on-duty gas guns (11); the outlet of the central wind barrel (9) is provided with a rotational flow combustion stabilizing cover (10), and the part of the central wind barrel (9) in the combustor shell (1) is provided with a plurality of air inlets (901).
2. A multi-nozzle air-distribution low-nitrogen burner according to claim 1, characterized in that the combustion-supporting air nozzles (5) comprise 5-25 small nozzles arranged on the same reference circle; the outlet of the combustion-supporting air nozzle (5) is a contraction-shaped nozzle, and the contraction angle is 20-45 degrees.
3. The multi-nozzle air distribution low-nitrogen burner according to claim 2, characterized in that the direction of the combustion-supporting air nozzles (5) extending into the hearth is vector, so that the combustion-supporting air has axial velocity, tangential velocity and radial velocity; the combustion-supporting air nozzle (5) is expanded outwards, and an included angle alpha between the combustion-supporting air nozzle and the central shaft of the combustor is 10-30 degrees; the rotation angle beta of the combustion-supporting air nozzle (5) relative to the central shaft of the inlet of the nozzle is 15-45 degrees.
4. The multi-nozzle air distribution low-nitrogen burner according to claim 1, characterized in that the main gas gun (12) is provided with a plurality of premixed gas jet holes (1200) within the burner shell (1) and within 100-500 mm from the combustion-supporting air to the interface of the furnace chamber, part of the gas is injected into the burner shell (1) as premixed gas and is mixed with the combustion-supporting air and then is fed into the furnace chamber; the premixed gas amount is 10% -30% of the total gas amount, and the gas concentration after the premixed gas and the combustion-supporting air are mixed is below the lower explosion limit.
5. The multi-nozzle air distribution low-nitrogen burner as claimed in claim 1, wherein one end of the central wind cylinder (9) extends to the outside of the burner housing (1), a burner block (6) is sleeved outside the part of the central wind cylinder (9) extending out of the burner housing, and the combustion-supporting air entering from the wind inlet (901) accounts for 5% -30% of the total combustion-supporting air.
6. The multi-nozzle air distribution low-nitrogen burner as claimed in claim 1, wherein the end of the on-duty gas gun (11) is provided with a plurality of on-duty gas jet holes (1101), after part of the gas is jetted out through the on-duty gas jet holes (1101), a part of the gas is jetted onto the burner block (6) tangentially to heat the burner block, and a part of the gas is jetted to the periphery of the burner, and the amount of the on-duty gas is 1-7% of the total gas amount.
7. The multi-nozzle air distribution low-nitrogen combustor as claimed in claim 1, wherein the end of the main gas gun head (13) is provided with a plurality of main gas jet holes (1300), and the included angles between the main gas jet holes (1300) and the central axis of the combustor are different from 0 degree to 30 degrees.
CN202020301948.1U 2020-03-12 2020-03-12 Multi-nozzle air distribution low-nitrogen combustor Active CN212108382U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202020301948.1U CN212108382U (en) 2020-03-12 2020-03-12 Multi-nozzle air distribution low-nitrogen combustor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202020301948.1U CN212108382U (en) 2020-03-12 2020-03-12 Multi-nozzle air distribution low-nitrogen combustor

Publications (1)

Publication Number Publication Date
CN212108382U true CN212108382U (en) 2020-12-08

Family

ID=73634645

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202020301948.1U Active CN212108382U (en) 2020-03-12 2020-03-12 Multi-nozzle air distribution low-nitrogen combustor

Country Status (1)

Country Link
CN (1) CN212108382U (en)

Similar Documents

Publication Publication Date Title
CN208920103U (en) The axially staged combustion chamber of gas turbine
CN212108382U (en) Multi-nozzle air distribution low-nitrogen combustor
CN107543160A (en) A kind of ultralow nitrogen gas burner
CN210004388U (en) kinds of low-nitrogen burner
CN107461742B (en) Graded flameless low-nitrogen combustion head
CN212005662U (en) Fuel side flue gas recirculation low-nitrogen combustor
CN204901756U (en) Partly mix low NOx burner in advance
CN211424389U (en) Gas burner
CN209926348U (en) Low-nitrogen combustor system with flue gas double-path circulation and combustion area division
WO2021027094A1 (en) Combustion apparatus for upper combustion chamber of sleeve kiln
CN211902870U (en) High-temperature flue gas multi-stage backflow low-nitrogen combustor
CN109442411B (en) Low-nitrogen burner for gas fuel
CN211650224U (en) Gas burner
CN215336318U (en) Low-pollution burner head structure
CN211040961U (en) Ultralow nitrogen gas burner
CN214275709U (en) Hierarchical low-nitrogen combustor
CN212408648U (en) Flue gas self-circulation low-nitrogen combustion head
CN211399780U (en) Ultralow NOx gas shower nozzle device based on flue gas extrinsic cycle technique
CN215001584U (en) Novel mixed combustor for coal, gas and oil
CN212929987U (en) Vortex nozzle device for reducing nitrogen oxide emission in low-nitrogen combustor
CN111121023A (en) Fuel side flue gas recirculation nitrogen combustor and combustion method thereof
CN212430861U (en) High-stable-combustion afterburning burner device
CN212565756U (en) Low-nitrogen combustor
CN210165376U (en) Low-nitrogen combustor and low-nitrogen combustion system
CN210179628U (en) Ultralow-nitrogen combustion system for low-calorific-value gas

Legal Events

Date Code Title Description
GR01 Patent grant
GR01 Patent grant