CN108361690B - Anti-slagging low NOx burner with remote over-fire air - Google Patents
Anti-slagging low NOx burner with remote over-fire air Download PDFInfo
- Publication number
- CN108361690B CN108361690B CN201810084060.4A CN201810084060A CN108361690B CN 108361690 B CN108361690 B CN 108361690B CN 201810084060 A CN201810084060 A CN 201810084060A CN 108361690 B CN108361690 B CN 108361690B
- Authority
- CN
- China
- Prior art keywords
- air
- remote over
- fire
- pipe
- inner secondary
- 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
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D1/00—Burners for combustion of pulverulent fuel
- F23D1/02—Vortex burners, e.g. for cyclone-type combustion apparatus
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N3/00—Regulating air supply or draught
- F23N3/007—Regulating air supply or draught using mechanical means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D2201/00—Burners adapted for particulate solid or pulverulent fuels
- F23D2201/20—Fuel flow guiding devices
Abstract
The invention discloses a slag-bonding prevention type low NOx burner with remote over-fire air, which comprises a burner body, a precombustion chamber and a remote over-fire air pipe, wherein a remote over-fire air baffle is arranged in the remote over-fire air pipe, the burner body is communicated with an inlet of the precombustion chamber, an outlet of the remote over-fire air pipe and an outlet of the precombustion chamber are communicated with an inlet of a hearth, and the burner prevents slag bonding at a nozzle of the precombustion chamber of the burner.
Description
Technical Field
The invention belongs to the technical field of pulverized coal combustion, and relates to an anti-slagging low NOx burner with remote over-fire air.
Background
Coal as a leading energy resource in China cannot be changed in a medium-long term, and a coal-fired power plant and an industrial boiler as a leading coal combustion utilization mode cannot be changed. However, with the increasing severity of environmental pollution, nitrogen oxides, sulfur oxides and particulate matters discharged in the coal combustion process are receiving wide attention from countries all over the world.
Coal-fired power plants and industrial boilers are the main sources of emission of coal-fired atmospheric pollutants, especially nitrogen oxides. Therefore, optimizing the burner design as the most direct economic way to reduce NOx is the hot spot of current pulverized coal combustion and NOx abatement research. The low primary air rate carries coal powder to enter a combustor, and the coal powder is pyrolyzed and devolatilized under the low-oxygen and low-temperature condition and is subjected to anoxic combustion to form a local low-temperature reducing atmosphere to reduce the NOx precursor into N2Fuel-type and thermal-type NOx generation is reduced. Meanwhile, the concentration separation of the coal dust can further promote the ignition of coal dust airflow and reduce the generation of NOx.
Coal quality variability is an important challenge facing pulverized coal boilers under market economic conditions. Coal quality is changeable and directly influences the characteristics of pulverized coal ignition, stable combustion, NOx generation and the like. The inner secondary air rotational flow enables high-temperature flue gas at the rear part of the combustor to flow back to the root part of the combustor, and ignition and subsequent stable combustion of pulverized coal airflow are promoted. When the coal quality is poor, the rotational flow strength needs to be increased, the entrainment of high-temperature flue gas is promoted, and the ignition and stable combustion of the pulverized coal are ensured; if the coal quality is good, the rotational flow strength or the oxygen content can be properly reduced, a low-oxygen low-temperature environment is formed, and the generation of NOx is reduced. Therefore, under the condition of variable coal quality, the adaptability of the coal type of the combustor can be obviously enhanced by adjusting the internal secondary air quantity and the rotational flow strength, and the efficiency and the reliability of the boiler and the economical efficiency of a power plant are ensured.
The biomass, the east Junggar coal and other alkali metal enriched fuels contain high volatile components, and the generation of NOx can be remarkably reduced by pre-combustion; however, the high alkali metal content results in lower ash melting point and severe slag bonding. Along with the promulgation of biomass mixed combustion policy, the development and application of low-price high-reserve east-oriented coal and the variable coal quality condition, slag bonding at the root of a combustor frequently occurs. When coal powder ignition and low NOx generation are ensured, cold direct-current remote over-fire air is introduced to the periphery of a nozzle of a combustor precombustion chamber to isolate peripheral high-temperature flue gas from flowing back, a cooling effect is achieved, the temperature of the nozzle of the combustor can be obviously reduced, and slagging is prevented.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a slag-forming-prevention low NOx burner with remote over-fire air, which prevents slag formation of a burner pre-combustion chamber nozzle.
In order to achieve the purpose, the anti-slagging low NOx burner with the remote over-fire air comprises a burner body, a pre-combustion chamber and a remote over-fire air pipe, wherein a remote over-fire air baffle is arranged in the remote over-fire air pipe, the burner body is communicated with an inlet of the pre-combustion chamber, and an outlet of the remote over-fire air pipe and an outlet of the pre-combustion chamber are communicated with an inlet of a hearth.
The burner body comprises a central pipe, a primary air pipe, an inner secondary air pipe and an outer secondary air pipe;
the central tube, the primary air duct, the inner secondary air duct and the outer secondary air duct are distributed from inside to outside in sequence, the end part of the inner secondary air duct is provided with an inner secondary air annular channel flaring, the primary air duct is internally provided with a pulverized coal concentrator, the central tube is internally provided with an ignition oil gun and an igniter, and the central tube, the primary air duct, the inner secondary air annular channel flaring and the outer secondary air duct are all communicated with an inlet of the precombustion chamber.
The remote over-fire air duct is sleeved on the outer wall of the precombustion chamber.
An inner secondary air baffle is arranged in an inlet channel of the inner secondary air pipe, an outer secondary air baffle is arranged in an inlet channel of the outer secondary air pipe, the inner secondary air baffle and the outer secondary air baffle are coaxially linked, and the inner secondary air baffle and the outer secondary air baffle are vertically arranged.
The pulverized coal concentrator is of an annular trapezoidal structure.
A plurality of fixed tangential rotational flow blades are arranged in the inlet pipeline of the inner secondary air pipe along the circumferential direction.
The invention has the following beneficial effects:
the anti-slagging low NOx burner with the remote over-fire air comprises a burner body, a precombustion chamber and a remote over-fire air pipe, wherein direct-current remote over-fire air is injected into a hearth at a high speed through the remote over-fire air pipe to isolate the backflow of high-temperature flue gas around the precombustion chamber, so that the outlet of the precombustion chamber is cooled, the jet of the precombustion chamber is in a low-temperature environment, the slagging of a nozzle of the precombustion chamber of the burner is prevented, and the burner is simple in structure, convenient to operate and extremely strong in usability.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic structural view of a stationary tangential swirl vane of the present invention.
Wherein, 1 is a primary air pipe, 2 is a fixed tangential swirl vane, 3 is an inner secondary air baffle, 4 is an outer secondary air baffle, 5 is an inner secondary air pipe, 6 is an outer secondary air pipe, 7 is a remote over-fire air baffle, 8 is a remote over-fire air pipe, 9 is a precombustion chamber, 10 is an inner secondary air annular channel flaring, 11 is a pulverized coal concentrator, 12 is a central pipe, 13 is an igniter, and 14 is an ignition oil gun.
Detailed Description
The invention is described in further detail below with reference to the accompanying drawings:
referring to fig. 1 and 2, the anti-slagging low NOx burner with remote overfire air comprises a burner body, a precombustion chamber 9 and a remote overfire air duct 8, wherein a remote overfire air baffle 7 is arranged in the remote overfire air duct 8, the burner body is communicated with an inlet of the precombustion chamber 9, and an outlet of the remote overfire air duct 8 and an outlet of the precombustion chamber 9 are communicated with an inlet of a hearth.
The burner body comprises a central pipe 12, a primary air pipe 1, an inner secondary air pipe 5 and an outer secondary air pipe 6; the central tube 12, the primary air duct 1, the inner secondary air duct 5 and the outer secondary air duct 6 are sequentially distributed from inside to outside, an inner secondary air annular channel flaring 10 is arranged at the end part of the inner secondary air duct 5, a pulverized coal concentrator 11 is arranged in the primary air duct 1, an ignition oil gun 14 and an igniter 13 are arranged in the central tube 12, and the central tube 12, the primary air duct 1, the inner secondary air annular channel flaring 10 and the outer secondary air duct 6 are all communicated with an inlet of the precombustion chamber 9.
The remote over-fire air duct 8 is sleeved on the outer wall of the precombustion chamber 9; an inner secondary air baffle 3 is arranged in an inlet channel of the inner secondary air pipe 5, an outer secondary air baffle 4 is arranged in an inlet channel of the outer secondary air pipe 6, wherein the inner secondary air baffle 3 is coaxially linked with the outer secondary air baffle 4, and the inner secondary air baffle 3 is vertically arranged with the outer secondary air baffle 4.
The pulverized coal concentrator 11 is of an annular trapezoidal structure; a plurality of fixed tangential rotational flow blades 2 are arranged in the inlet pipeline of the inner secondary air duct 5 along the circumferential direction.
The working principle of the invention is as follows:
the invention adopts the configuration of inner secondary air, outer secondary air and remote over-fire air, controls the low-oxygen environment in the precombustion chamber 9 by adjusting the proportion of the secondary air and the remote over-fire air, directly injects the direct-current remote over-fire air into the hearth to isolate high-temperature flue gas at the periphery of the outlet of the precombustion chamber 9, cools the outlet position of the precombustion chamber 9, and reduces the temperature at the outlet of the precombustion chamber 9 to prevent and treat slagging. A plurality of fixed tangential swirl vanes 2 are arranged in the inlet channel of the inner secondary air duct 5 along the circumferential direction, the inner secondary air is changed into the inner secondary air of the swirl through the fixed tangential swirl vanes 2, the inner secondary air of the swirl sucks high-temperature flue gas at the rear part of the precombustion chamber 9 after entering the precombustion chamber 9 through the flaring 10 of the annular channel of the inner secondary air, and the primary air pulverized coal airflow is promoted to catch fire in time. Under the condition of ensuring that the air volume ratio of the secondary air to the remote over-fire air is not changed, the air volume ratio of the secondary air in the rotational flow to the direct-current external secondary air is adjusted by adjusting the opening degrees of the inner secondary air baffle 3 and the outer secondary air baffle 4, and the intensity of the rotation and the smoke entrainment are controlledAnd thus the temperature of the prechamber 9. The primary air pulverized coal airflow is pyrolyzed to remove volatile components and is subjected to anoxic combustion in the precombustion chamber 9 to generate a local reducing atmosphere, so that NOx is reduced to N2. Meanwhile, the low-oxygen low-temperature environment in the pre-combustion chamber 9 is favorable for inhibiting the generation of thermal NOx, ensures that pulverized coal airflow is quickly ignited and stably combusted, effectively reduces the generation of NOx, and simultaneously prevents and controls the nozzle slagging of the combustor.
The specific working process of the invention is as follows:
the outer secondary air baffle 4 is opened to purge the precombustion chamber 9, the purging time is more than or equal to 2min, the igniter 13 is opened again to ensure the normal work of the igniter 13, the igniter 13 is inserted and ignited, then the mixture of primary air and pulverized coal is introduced, after the pulverized coal is ignited, the inner secondary air baffle 3 and the remote over-fire air baffle 7 are opened, the pulverized coal is quickly preheated in the precombustion chamber 9, the pulverized coal is pyrolyzed to generate volatile matters for ignition, and the precombustion chamber 9 mainly maintains the high temperature thereof by means of volatile matter combustion. The oxygen amount in the precombustion chamber 9 is controlled by controlling the opening of the remote over-fire air baffle 7, the opening of the inner secondary air baffle 3 and the opening of the outer secondary air baffle 4, the swirl strength of the inner secondary air is controlled by adjusting the circumferential rotation scheduling of the inner secondary air baffle 3 and the outer secondary air baffle 4, and further the temperature of the precombustion chamber 9 is controlled below 1000 ℃, so that nitrogen-containing compounds generated by coal powder pyrolysis are reduced into N2(ii) a The preheated gas and coal powder mixture is directly sprayed into the hearth and then mixed with the remote over-fire air for combustion. When the temperature of the hearth is lower than 1200 ℃, the proportion of the inner secondary air is at least 30 percent, when the temperature of the hearth is higher than 1200 ℃, the air quantity of the inner secondary air is reduced, the entrainment of flue gas is reduced, the pulverized coal is combusted in a low-temperature low-oxygen reducing atmosphere, the generation of thermal NOx is reduced, and meanwhile, the NOx is reduced into N by a local reducing atmosphere2And the NOx generation amount is reduced.
The above-mentioned contents are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical idea of the present invention falls within the protection scope of the claims of the present invention.
Claims (3)
1. The anti-slagging low NOx burner with the remote over-fire air is characterized by comprising a burner body, a pre-combustion chamber (9) and a remote over-fire air duct (8), wherein a remote over-fire air baffle (7) is arranged in the remote over-fire air duct (8), the burner body is communicated with an inlet of the pre-combustion chamber (9), an outlet of the remote over-fire air duct (8) and an outlet of the pre-combustion chamber (9) are communicated with an inlet of a hearth, the remote over-fire air duct (8) is sleeved on the outer wall of the pre-combustion chamber (9), direct-current remote over-fire air is jetted into the hearth at a high speed through the remote over-fire air duct (8), and the opening degree of the remote over-fire air baffle (7) can control the amount of direct-current remote over-fire air;
the central pipe (12), the primary air pipe (1), the inner secondary cyclone air pipe (5) and the outer secondary direct-current air pipe (6) are distributed in sequence from inside to outside.
2. The anti-slagging low-NOx burner with remote over-fire air according to claim 1, characterized in that the burner body comprises a central pipe (12), a primary air duct (1), an inner secondary cyclone air duct (5) and an outer secondary direct-flow air duct (6);
the end part of the inner secondary cyclone air pipe (5) is provided with an inner secondary cyclone air annular channel flaring opening (10), the inner edge of the primary air pipe (1) is circumferentially provided with a trapezoidal pulverized coal concentrator (11), the central pipe (12) is internally provided with an ignition oil gun (14) and an igniter (13), and the central pipe (12), the primary air pipe (1), the inner secondary cyclone air annular channel flaring opening (10) and the outer secondary direct-current air pipe (6) are all communicated with the inlet of the precombustion chamber (9).
3. The anti-slagging low NOx burner with remote over-fire air is characterized in that an inner secondary cyclone air baffle (3) is arranged in an inlet channel of an inner secondary cyclone air pipe (5), an outer secondary direct-flow air baffle (4) is arranged in an inlet channel of an outer secondary direct-flow air pipe (6), wherein the inner secondary cyclone air baffle (3) and the outer secondary direct-flow air baffle (4) are coaxially linked, the inner secondary cyclone air baffle (3) and the outer secondary direct-flow air baffle (4) are vertically arranged, and a plurality of fixed tangential cyclone blades (2) are circumferentially arranged in an inlet pipeline of the inner secondary cyclone air pipe (5).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810084060.4A CN108361690B (en) | 2018-01-29 | 2018-01-29 | Anti-slagging low NOx burner with remote over-fire air |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810084060.4A CN108361690B (en) | 2018-01-29 | 2018-01-29 | Anti-slagging low NOx burner with remote over-fire air |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108361690A CN108361690A (en) | 2018-08-03 |
| CN108361690B true CN108361690B (en) | 2020-01-10 |
Family
ID=63007493
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810084060.4A Active CN108361690B (en) | 2018-01-29 | 2018-01-29 | Anti-slagging low NOx burner with remote over-fire air |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108361690B (en) |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IT1231511B (en) * | 1989-09-08 | 1991-12-07 | Ente Naz Energia Elettrica | IMPROVEMENTS IN A FUEL BURNER FOR A BOILER |
| US5199866A (en) * | 1992-03-30 | 1993-04-06 | Air Products And Chemicals, Inc. | Adjustable momentum self-cooled oxy/fuel burner for heating in high temperature environments |
| CN101725969B (en) * | 2010-01-19 | 2011-08-17 | 中国计量学院 | Low-NOx pulverized coal burner |
| CN201680364U (en) * | 2010-04-06 | 2010-12-22 | 山西蓝天环保设备有限公司 | Efficient low NOx pulverized coal burner for small and medium-sized industrial boilers |
| CN205690390U (en) * | 2016-05-24 | 2016-11-16 | 北京中标新亚节能工程股份有限公司 | Low NO |
| CN106287667B (en) * | 2016-10-08 | 2018-10-30 | 西安交通大学 | A kind of high temperature gases recirculating preheating type low-NOx combustor equipped with SOFA |
-
2018
- 2018-01-29 CN CN201810084060.4A patent/CN108361690B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN108361690A (en) | 2018-08-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110822423B (en) | Multi-purpose burner with fins and different-diameter gas self-rotating premixing function | |
| CN208154470U (en) | A kind of remote burnout degree second level eddy flow wide regulating ratio low-NOx combustor | |
| CN107525067B (en) | Central powder feeding rotational flow pulverized coal combustion device capable of preventing slag bonding of water-cooled wall | |
| CN110793195B (en) | Hot-blast furnace equipment suitable for low-heating-value fuel low-oxygen combustion | |
| CN204042867U (en) | A kind of low-NO_x burner system | |
| CN110425520B (en) | Flameless combustion system for semi-coke type flame-retardant fuel | |
| CN208779450U (en) | A kind of ultralow NOX combustion system and its burner of low-load combustion-stabilizing | |
| CN113339789A (en) | Coking-prevention pulverized coal burner with horseshoe-shaped turbulence teeth | |
| CN108413382B (en) | Burner for single combustion or mixed combustion of biomass and natural gas | |
| CN110848667B (en) | Low-calorific-value nitrogen-containing gas combustion system and method | |
| CN109931597B (en) | Fuel staged gasification and low NOXCombustion boiler | |
| CN208418734U (en) | A kind of low-NOx combustor for natural gas and coal dust | |
| CN108361690B (en) | Anti-slagging low NOx burner with remote over-fire air | |
| CN109442411B (en) | Low-nitrogen burner for gas fuel | |
| CN101666490B (en) | Burning system for directly burning low-volatilization powder carbocoal by using high-temperature air | |
| CN208418701U (en) | A kind of low-NOx combustor for biomass and combustion of natural gas | |
| WO2023071260A1 (en) | Turbulent burner capable of simultaneously burning nh3 and pulverized coal | |
| CN104154532A (en) | Center air ring concentrated type turbulent burner | |
| CN211781036U (en) | Low-nitrogen combustion device for enhancing pulverized coal gasification | |
| CN108397774A (en) | It is a kind of to be used for natural gas and the coal dust individually burner of burning or multifuel combustion | |
| CN210050797U (en) | Pollutant ultra-low discharge cyclone pulverized coal burner | |
| CN110848692B (en) | Air shunting spinning part premixing dual-fuel low NOx burner | |
| CN210291864U (en) | Industrial pulverized coal boiler burner with secondary air axial blades with adjustable angle | |
| CN110887037A (en) | Low-nitrogen combustion device for enhancing pulverized coal gasification | |
| CN101334162A (en) | Station boiler anthracite powder combustion plant |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| EE01 | Entry into force of recordation of patent licensing contract |
Application publication date: 20180803 Assignee: Ningxia Xingjian boiler and vessel Co.,Ltd. Assignor: XI'AN JIAOTONG University Contract record no.: X2020610000006 Denomination of invention: Anti-slagging low-NOx burner with remote over-fire air Granted publication date: 20200110 License type: Common License Record date: 20200715 |
|
| EE01 | Entry into force of recordation of patent licensing contract |