CN101936529B - Sidewall gas burner capable of reducing emission of nitrogen oxides - Google Patents
Sidewall gas burner capable of reducing emission of nitrogen oxides Download PDFInfo
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- CN101936529B CN101936529B CN 201010296282 CN201010296282A CN101936529B CN 101936529 B CN101936529 B CN 101936529B CN 201010296282 CN201010296282 CN 201010296282 CN 201010296282 A CN201010296282 A CN 201010296282A CN 101936529 B CN101936529 B CN 101936529B
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Abstract
The invention provides a sidewall gas burner capable of reducing the emission of nitrogen oxides. The sidewall gas burner mainly comprises a silencing cover (1), a secondary air damper (2), a primary air damper (3), an air inlet pipe (4), a fuel nozzle (5), an injector (6), a primary nozzle (7), a secondary nozzle (8) and a nozzle brick (9), wherein a part of fuel gas injects primary combustion air through the injector (6) and is mixed with the primary combustion air and then sprayed into a hearth for combustion through the primary nozzle (7); secondary combustion air enters the hearth for combustion through clearance between the nozzle brick (9) and the primary nozzle (7); and the rest part of fuel gas is sprayed into the hearth through the secondary nozzle (8) extended through the primary nozzle (7), so that secondary fuels are mixed with smoke before entering a combustion area. The sidewall gas burner has the advantages of particular suitability for a cracking furnace, wall-adherent flame combustion, good combustion status, low noise, convenient maintenance and the realization of the low emission of the nitrogen oxides.
Description
Technical field
The present invention relates to a kind of side-wall gas burner that reduces discharged nitrous oxides, particularly a kind of is adherent flame, low noise, the low NOx gas burner of fuel with fuel gas, is specially adapted on the ethane cracking furnace.
Background technology
Burner is one of critical piece of ethane cracking furnace, and most of pyrolysis furnaces have adopted the mode of radiant wall burner and base burning device combined heat, and this configuration mode can obtain boiler tube axial temperature distribution uniformly.Along with the pay attention to day by day to environmental protection, the height of NOx content becomes one of important indicator of weighing the burner combustion performance, and burner manufacturer has also developed various types of low-NOx combustors in succession.
The low-NOx combustor that uses at present mainly contains three kinds.First kind is the classification air burner, makes combustion air shunting setting up first combustion zone of oxygen deprivation, thereby reduces the formation of NOx, in second combustion zone air of remainder is introduced, thereby is accomplished whole combustion process.Second kind is the classification fuel burner, and combustion air is once all introduced first combustion zone, but has only part of fuel to be burnt in first combustion zone, and remaining fuel is introduced in second combustion zone, utilizes the superfluous oxygen in first combustion zone to burn.In this burner, the superfluous air in first combustion zone has diluted fuel, and ignition temperature is lower, thereby reduces the formation of NOx.The third is the flue gas recirculation burner, and the low-pressure area that utilizes combustion air or fuel gas stream to produce makes flue gas recirculation in the combustion zone, and inertia flue gas cooling flame reduces partial pressure of oxygen, thereby reduces the formation of NOx.
The technology in early stage and burner are being obtained success in various degree aspect the reduction NOx discharging; But be applied to the base burning device usually; For radiant wall burner; Also need some improvement, except environmental requirement, many factors such as flame profile, flame diameter, heat flow density distribution and regular maintenance of going back the oppose side wall burner have very harsh requirement.
CN00247075.6 discloses a kind of side-wall gas burner; Mainly form by fuel gas inlet tube, injector, burner; Characteristics be outside the air inlet end is provided with, interior muffler and look fire hole, the port of export of fuel gas inlet tube is provided with the gas spray head that places in the injector, the injector front end is connected to burner; The burner head is bowl-shape, and its bowl portion periphery has several rectangle spray orifices; Injector, burner periphery are provided with burner block, are provided with secondary combustion air adjuster between outer muffler and the burner block.The adherent burning of this flame in gas burner, combustion position is good, and long service life is easy to operate, and noise is low, but owing to do not adopt low NOx combusting technology, the NOx discharging is higher relatively.Along with base burning device utilization new technology has reduced the NOx discharging, radiant wall burner becomes the capital equipment that influences ethane cracking furnace NOx discharging.
Summary of the invention
The object of the present invention is to provide a kind of side-wall gas burner that reduces discharged nitrous oxides; Particularly a kind of being applicable on the ethane cracking furnace is adherent flame, low noise, the low NOx gas burner of fuel with fuel gas; It not only can satisfy environmental requirement; Can also obtain good radiant wall burner flame profile, flame diameter and heat flow density and distribute, and be convenient to safeguard.
The objective of the invention is to realize like this:
A kind of side-wall gas burner that reduces discharged nitrous oxides; Mainly form by silencer cover 1, secondary air register 2, main air intake 3, air inlet pipe 4, fuel nozzle 5, injector 6, one-level burner 7, secondary burner 8, burner block 9; The port of export that it is characterized in that air inlet pipe 4 is with fuel nozzle 5 outward, and fuel nozzle 5 places in the injector 6, and fuel nozzle has several one-level fuel jet orifices 10 on 5 other end outers; Make a part of fuel gas of introducing from air inlet pipe 4 spray into injector 6 through one-level fuel jet orifice 10; Injector 6 ports of export are connected to one-level burner 7, and one-level burner 7 inner central tube chambeies 12 are with secondary burner 8, and outer chamber and injector 6 cavitys join; The central lumen 12 of one-level burner 7 expands outwardly into bowl-shape in the exit; The edge extends outside the burner block internal face, and bowl portion periphery has fire hole 11, and the fire hole direction is parallel with the burner block internal face; , fuel nozzle 5 these ends are with secondary burner 8 in going back; Secondary burner 8 is made up of secondary fuel distributing pipe 14 and secondary fuel shower nozzle 15; And in the porch of secondary burner 8 secondary fuel distributing pipe 14, be provided with secondary fuel spray orifice 18; Another part fuel gas that air inlet pipe 4 is introduced gets into secondary burner 8 through fuel nozzle 5, secondary fuel spray orifice 18, and the secondary fuel shower nozzle 15 of secondary burner 8 passes one-level burner 7 central lumen, and the bowl-type root has secondary fuel discharge orifice 16 in the exit.
The side-wall gas burner that the present invention can reduce discharged nitrous oxides adopts classification fuel and flue gas recirculation combustion technology; Part fuel gas is through injector 6 injection primary airs and mixing is after one-level burner 7 sprays into the burner hearth burning with it, and the secondary combustion air gets into burner hearth through the annular space between burner block 9 and the one-level burner 7 and participates in burning.The fuel gas of remainder sprays into secondary burner 8 by secondary fuel spray orifice 18, gets into burner hearth through the secondary fuel discharge orifice on the secondary fuel shower nozzle 15 16, and secondary fuel was mixed with flue gas earlier before getting into the combustion zone.In other words, fuel gas gets into from air inlet pipe, and one-level fuel sprays into injector by the one-level fuel jet orifice, and through injector injection primary air, one-level fuel gets into furnace combustion zone with after primary air mixes through the one-level burner in injector.The secondary combustion air that gets into burner hearth through annular space between burner block and the one-level burner is also participated in burning in the combustion zone.Remaining secondary fuel sprays into the secondary burner by the secondary fuel spray orifice; Get in the burner hearth apart from the position enough far away that is separated by, combustion zone through the discharge orifice on the secondary fuel shower nozzle; Secondary fuel was mixed with flue gas earlier before getting into the combustion zone; The low-pressure area that utilizes the secondary fuel air-flow to produce makes flue gas recirculation in the combustion zone.
More specifically give an example, 3～8 one-level fuel jet orifices 10 that are uniformly distributed along the circumference can be arranged on the fuel nozzle 5, the angle of one-level fuel jet orifice and fuel nozzle axis is 5～10 °.Be provided with central lumen 12 in the one-level burner 7 and be convenient to secondary burner 8 and extend through it, central lumen 12 outlets also can have polygon groove 13, and the polygon boss 17 that is complementary with polygon groove 13 is arranged on the secondary fuel shower nozzle 15 of secondary burner 8.The secondary fuel shower nozzle can have 3～8 secondary fuel discharge orifices 16 on the 15 outlet end outers; The secondary fuel discharge orifice can circumferentially be uniformly distributed with in the face of claiming layout or edge along the vertical axis of secondary fuel shower nozzle; Secondary fuel discharge orifice countershaft wire clamp angle β is 45～120 °, and the angle γ of secondary fuel discharge orifice and secondary fuel shower nozzle axis is 60～80 °.
It is cotton that silencer cover 1 inside preferably is lined with two-layer noise reduction in the side-wall gas burner of the present invention.
When use is of the present invention, preferably adopt computational fluid dynamics (CFD) method to carry out the design of injector 6, one-level burner 7 and secondary burner 8 runners; Adopt computational fluid dynamics (CFD) method to confirm the fire hole 11 of one-level fuel jet orifice 10, secondary fuel spray orifice 18, one-level burner, quantity, layout and the orientation of secondary fuel discharge orifice 16, thereby obtain gratifying flame and heat flux distribution.The fire hole 11 of one-level burner (preferably rectangle fire hole) edge is 4～10mm far from burner block 9 inner wall edges, is preferably 5mm.The burning load of one-level burner 7 preferably accounts for 50%～80% of total fuel; The burning load of secondary burner 8 preferably accounts for 50%～20% of total fuel.
The present invention is the improvement of CN00247075.6; In order to reduce discharged nitrous oxides; The present invention has adopted fuel staging and flue gas recirculation combustion technology, and fuel is divided into secondary and injects the combustion zone, and one-level fuel and whole combustion airs are in furnace combustion zone mixed combustion; Superfluous combustion air has cooled off flame temperature, thereby reduces the generation of NOx.Remaining secondary fuel mixes with flue gas earlier before getting into the combustion zone, and the low-pressure area that utilizes the secondary fuel air-flow to produce makes flue gas recirculation in the combustion zone; Accomplish burning with the combustion air of surplus; Because the inertia flue gas has cooled off flame, and has reduced partial pressure of oxygen, thereby reduce the generation of NOx.Compare with the side-wall gas burner of CN00247075.6, NOx discharging of the present invention can reduce more than 50%, is lower than 40ppmvd.
Side-wall gas burner of the present invention is particularly suitable on pyrolysis furnace, using, the adherent burning of flame, and combustion position is good, and noise is low, and realizes low-nitrogen oxide discharging; And burner of the present invention safeguard and control on simpler, regulate than the ratio of minimum load (the burner peak load with) and can reach 5:1, the operator who allows pyrolysis furnace optimize and stable heat flux characteristics under operate.
Of the present invention other with further target, feature and advantage through further describing in the following specific embodiment and the accompanying drawing.
Description of drawings
Fig. 1 is the structural representation of burner of the present invention;
Fig. 2 is the cutaway view of burner fuel nozzle of the present invention;
Fig. 3 is that the A of Fig. 2 is to view;
Fig. 4 is the cutaway view of burner one-level burner of the present invention;
Fig. 5 is the cutaway view of burner secondary burner of the present invention;
Fig. 6 is that the B of Fig. 5 is to view.
The specific embodiment
As shown in Figure 1 is a kind of low noise, low NOx side-wall gas burner that is used for ethane cracking furnace of the present invention of using, and mainly is made up of silencer cover 1, secondary air register 2, main air intake 3, air inlet pipe 4, fuel nozzle 5, injector 6, one-level burner 7, secondary burner 8, burner block 9.It only is a kind of form of the present invention, and the present invention is not limited to this.
Consult Fig. 1; Fuel gas gets into from air inlet pipe 4; Part sprays into the one-level fuel of injector 6 through fuel nozzle 5, through injector 6 injection primary airs with after one-level fuel mixes in the annular space of 8 of injector 6 and secondary burners, through one-level burner 7 entering furnace combustion zone.The secondary combustion air that gets into burner hearth through annular space between burner block 9 and the one-level burner 7 is also participated in burning in the combustion zone.The secondary fuel of remainder gets into through fuel nozzle 5 and extends through the secondary burner 8 of one-level burner 7 and spray into burner hearth, and the low-pressure area that the secondary fuel air-flow produces can make flue gas recirculation in the combustion zone, the final completing combustion of fuel.
Consult Fig. 1,2,3; Fuel nozzle 5 is arranged in the injector 6, is with air inlet pipe 4 in the one of which end, is with secondary burner 8 in the other end; 3 one-level fuel jet orifices 10 that are uniformly distributed with are arranged on the fuel nozzle 5, and one-level fuel jet orifice 10 is 9 ° with the angle of fuel nozzle 5 axis.
Consult Fig. 1,4, establish in the one-level burner 7 and be convenient to secondary burner 8 and extend through its central lumen 12 and polygon groove 13, central lumen expands outwardly into bowl-shape in the exit, and bowl portion periphery has several rectangle fire holes 11.
Consult Fig. 4,5,6, secondary burner 8 is made up of secondary fuel distributing pipe 14 and secondary fuel shower nozzle 15, has one and the polygon boss 17 that is complementary of the polygon groove 13 of one-level burner on the secondary fuel shower nozzle 15.
Consult Fig. 5,6; Secondary fuel distributing pipe 14 arrival ends have secondary fuel spray orifice 18; 3 secondary fuel discharge orifices 16 are arranged on the secondary fuel shower nozzle 15, and secondary fuel discharge orifice 16 countershaft wire clamp angle β are 45 °, and secondary fuel discharge orifice 16 is 70 ° with the angle γ of secondary fuel shower nozzle 15 axis.
The design of the runner of injector 6, one-level burner 7, secondary burner 8 adopts computational fluid dynamics (CFD) method to carry out among Fig. 1.
The design of one-level fuel jet orifice 10, one-level burner fire hole 11, secondary fuel spray orifice 18, secondary fuel discharge orifice 16 among Fig. 2,3,4,5,6, layout, quantity and orientation adopt computational fluid dynamics (CFD) method to design.
This side-wall gas burner NOx discharging is lower than 40ppmvd, and flame is adherent, convenient operating maintenance.
Claims (7)
1. side-wall gas burner that can reduce discharged nitrous oxides; Mainly form by silencer cover (1), secondary air register (2), main air intake (3), air inlet pipe (4), fuel nozzle (5), injector (6), one-level burner (7), secondary burner (8), burner block (9); The port of export that it is characterized in that air inlet pipe (4) is with fuel nozzle (5) outward; Fuel nozzle (5) places in the injector (6); Have several one-level fuel jet orifices (10) on fuel nozzle (5) other end outer, make a part of fuel gas of introducing from air inlet pipe (4) spray into injector (6) through one-level fuel jet orifice (10), injector (6) port of export is connected to one-level burner (7); One-level burner (7) inner central tube chamber (12) is with secondary burner (8); Outer chamber and injector (6) cavity joins, and the central lumen (12) of one-level burner (7) expands outwardly into bowl-shape in the exit, and the edge extends outside the burner block internal face; Bowl portion periphery has fire hole (11), and the fire hole direction is parallel with the burner block internal face; Be with secondary burner (8) at this end of fuel nozzle (5) in also; Secondary burner (8) is made up of secondary fuel distributing pipe (14) and secondary fuel shower nozzle (15); And in the porch of secondary burner (8) secondary fuel distributing pipe (14), be provided with secondary fuel spray orifice (18); Another part fuel gas that air inlet pipe (4) is introduced gets into secondary burner (8) through fuel nozzle (5), secondary fuel spray orifice (18), and the secondary fuel shower nozzle (15) of secondary burner (8) passes one-level burner (7) central lumen, and the bowl-type root has secondary fuel discharge orifice (16) in the exit.
2. side-wall gas burner according to claim 1 is characterized in that the one-level fuel jet orifice (10) that has 3～8 to be uniformly distributed along the circumference on the fuel nozzle (5), and one-level fuel jet orifice (10) is 5～10 ° with the angle of fuel nozzle (5) axis.
3. side-wall gas burner according to claim 1; It is characterized in that being provided with in the one-level burner (7) central lumen (12); Be with secondary burner (8) in the central lumen (12), the central lumen outlet also has polygon groove (13), and the exit expands outwardly into bowl-shape then; The secondary fuel shower nozzle (15) of secondary burner (8) is provided with the polygon boss (17) that is complementary with the polygon groove of one-level burner (13); The secondary fuel shower nozzle (15) of secondary burner (8) passes one-level burner (7) central lumen, and boss is embedded in the groove.
4. side-wall gas burner according to claim 3; The bowl-type root has 3～8 secondary fuel discharge orifices (16) in the exit to it is characterized in that secondary fuel shower nozzle (15), and secondary fuel discharge orifice (16) circumferentially is uniformly distributed with in the face of claiming layout or edge along the vertical axis of secondary fuel shower nozzle (15).
5. side-wall gas burner according to claim 4 is characterized in that secondary fuel discharge orifice (16) countershaft wire clamp angle β is 45～120 °, and secondary fuel discharge orifice (16) is 60～80 ° with the angle γ of secondary fuel shower nozzle (15) axis.
6. side-wall gas burner according to claim 1 is characterized in that silencer cover (1) inside is lined with two-layer noise reduction cotton.
7. side-wall gas burner according to claim 1, fire hole (11) edge that it is characterized in that the one-level burner is far from burner block (9) inner wall edge 4～10mm.
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201010296282 CN101936529B (en) | 2010-09-29 | 2010-09-29 | Sidewall gas burner capable of reducing emission of nitrogen oxides |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201010296282 CN101936529B (en) | 2010-09-29 | 2010-09-29 | Sidewall gas burner capable of reducing emission of nitrogen oxides |
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| CN101936529A CN101936529A (en) | 2011-01-05 |
| CN101936529B true CN101936529B (en) | 2012-05-23 |
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105570936A (en) * | 2016-01-08 | 2016-05-11 | 上海梓扬机电设备有限公司 | Gas stove energy saving and noise reduction device |
| CN106838900A (en) * | 2017-02-20 | 2017-06-13 | 海湾环境科技（北京）股份有限公司 | Burner and fuel gas buring method |
| CN106989387A (en) * | 2017-02-22 | 2017-07-28 | 北京航空航天大学 | The low NOx gas burners of side wall fractional combustion and its combustion method |
| CN111594832A (en) * | 2020-05-09 | 2020-08-28 | 江苏焱鑫科技股份有限公司 | Negative-pressure self-suction type low-nitrogen combustor with internal circulation of flue gas and working method thereof |
| CN113932613A (en) * | 2021-10-29 | 2022-01-14 | 咸宁南玻玻璃有限公司 | Connecting structure of kiln nozzle brick and kiln nozzle |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000130716A (en) * | 1998-10-23 | 2000-05-12 | Mitsubishi Heavy Ind Ltd | Burner ignition torch |
| CN200955740Y (en) * | 2006-09-15 | 2007-10-03 | 金永纯 | Gas burner |
| CN101251264A (en) * | 2008-03-27 | 2008-08-27 | 烟台海融电力技术有限公司 | Two-stage flame generator |
| CN101634451A (en) * | 2008-07-21 | 2010-01-27 | 上海凌云瑞升燃烧设备有限公司 | Low NOx stepped and staged combustion device |
| CN201547785U (en) * | 2009-12-03 | 2010-08-11 | 成庆刚 | Oil-saving and stable combustion pulverized coal burner with low NOx emission |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201819214U (en) * | 2010-09-29 | 2011-05-04 | 中国石油化工股份有限公司 | Sidewall gas burner capable of reducing nitrogen oxide emission |
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- 2010-09-29 CN CN 201010296282 patent/CN101936529B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000130716A (en) * | 1998-10-23 | 2000-05-12 | Mitsubishi Heavy Ind Ltd | Burner ignition torch |
| CN200955740Y (en) * | 2006-09-15 | 2007-10-03 | 金永纯 | Gas burner |
| CN101251264A (en) * | 2008-03-27 | 2008-08-27 | 烟台海融电力技术有限公司 | Two-stage flame generator |
| CN101634451A (en) * | 2008-07-21 | 2010-01-27 | 上海凌云瑞升燃烧设备有限公司 | Low NOx stepped and staged combustion device |
| CN201547785U (en) * | 2009-12-03 | 2010-08-11 | 成庆刚 | Oil-saving and stable combustion pulverized coal burner with low NOx emission |
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| CN101936529A (en) | 2011-01-05 |
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Address after: 100728 Beijing, Chaoyangmen, North Street, No. 22, No. Patentee after: Sinopec Corp. Patentee after: Tianhua Institute of Chemical Machinery & Automation Co., Ltd. Address before: 100728 Beijing, Chaoyangmen, North Street, No. 22, No. Patentee before: Sinopec Corp. Patentee before: Tianhua Chemical Machinery & Automation Research Inst. |