CN2869593Y - Staged Combustion Swirl Pulverized Coal Burner - Google Patents

Abstract

The utility model discloses a graded combustion swirling pulverized coal burner, which comprises a primary air elbow, an igniter, a diversion pipe with a flare, a double-cone flare, a pulverized coal classifier with a flare, a primary air The splitter tube, the inner primary air passage, the outer primary air passage, the flare of the guide pipe is located at the air inlet of the primary air elbow, the flare of the pulverized coal classifier faces away from the fire side, and the smallest inner diameter of the double-cone flare is larger than The diameter of the flared opening of the pulverized coal classifier is the largest, and the diameter of the primary air splitter is equal to or smaller than the smallest diameter of the pulverized coal classifier. It is also possible to set multiple pulverized coal classifiers along the centerline (K) in the primary air elbow, and the diameters of the multiple pulverized coal classifiers decrease in turn toward the fire side, and the maximum flare diameter of the latter pulverized coal classifier is equal to Or smaller than the smallest diameter of the previous pulverized coal classifier. The utility model is a swirl pulverized coal combustion device with high efficiency and low NOx emission, and also has the functions of saving fuel and preventing coking.

Description

The fractional combustion vortex burner

Technical field

The utility model relates to a kind of burner, and especially relating to a kind of is the burner of fuel with the coal dust.

Background technology

Nitrogen oxide (Nox) is the major pollutants that cause atmosphere pollution, and it destroys ecological environment except forming acid rain, can also form photochemical fog, is detrimental to health.By new GB 13223-2003 " thermal power plant's atmosphere pollutants emission standards ", require coal-burning boiler from January 1st, 2004, need satisfy Vdaf＞20%, its Nox＜450mg/Nm3,10%＜Vdaf＜20%, its Nox＜650mg/Nm3, Vdaf＜10%, its Nox＜1100mg/Nm3; And under concentration of emission prerequisite up to standard, to charge,, have tangible economic advantages for the operating cost that alleviates denitrification apparatus so reduce the Nox amount that produces when burning as far as possible to the Nox total emission volumn.

In power station equipment, the quadrangle tangential circle boiler is because the cigarette temperature deviation that its residual rotation produces has caused the temperature deviation, therefore along with station boiler develops to big capacity, high parameter, high efficiency direction, adopt the swirl flow combustion technology of swirl flow combustion to obtain market approval widely.But traditional turbulent burner has following drawback: its wind, secondary wind mix strong, cause temperature peak higher, make the Nox output big; And near coking water-cooling wall easily, bring harm to safe operation of the boiler; Primary air system does not carry out fractional combustion, so when its igniting and underload, need to consume a large amount of fuel oils.Therefore, research Nox discharging is low, and the low-load combustion-stabilizing ability is strong, and is can fuel-efficient swirl flow combustion technology during igniting great to realizing the harmonious development of China's economy, create to save the property social effect.

Summary of the invention

The utility model mainly is to solve the high technical problem of existing in prior technology burner Nox discharging.

The utility model also solves the indifferent and igniting of existing in prior technology burner underload simultaneously, the technical problem of the big and easy coking of boiler water wall of fuel consumption etc. when surely firing.

Above-mentioned technical problem of the present utility model is mainly solved by following technical proposals: comprise windbend pipe 1 one time, be positioned at the igniter 3 at windbend pipe 1 a straight section part center, the mozzle 12 that also comprises the band enlarging that the radian that is positioned at described windbend pipe 1 a sweep center and described windbend pipe 1 sweep adapt, be positioned at the biconial enlarging 2 behind the described mozzle 12, be positioned at the coal dust clasfficiator 15 of the band enlarging after the described biconial enlarging 2, be arranged at a wind shunting tube 6 behind the described coal dust clasfficiator 15, interior wind passage 14, an outer wind passage 13, the enlarging of described mozzle 12 is positioned at the air inlet of a described windbend pipe 1, the fiery dorsad side of the enlarging of described coal dust clasfficiator 15, the minimum place of the internal diameter of described biconial enlarging 2 is greater than the enlarging diameter maximum of described coal dust clasfficiator 15, and the diameter of described wind shunting tube 6 is equal to or less than the minimum place of diameter of described coal dust clasfficiator 15.

As preferably, in a windbend pipe 1, be provided with a plurality of coal dust clasfficiators 15 along center line K, a plurality of coal dust clasfficiators 15 reduce successively towards fiery side direction diameter, and the diameter of the enlarging maximum of a back coal dust clasfficiator 15 is equal to or less than the minimum place of diameter of previous coal dust clasfficiator 15.

As preferably, secondary air duct 10 and outer secondary air duct 17 in the outside of a windbend pipe 1 has, before being divided into by the dividing plates 18 of tubular in the described outer secondary air duct 17 secondary air duct 9 with after secondary air duct 11.

As preferably, be provided with cyclone 4 in a wind passage 13 outside, 9 are provided with cyclone 16 in the described preceding secondary air duct, and the air inlet place of secondary air duct 17 is provided with air door baffle plate 7 outside.

As preferably, dividing plate 18 be outside equipped with can slide along described dividing plate 18 front and back the guide shell 5 of band enlarging, the enlarging of described guide shell 5 is towards fiery side, and described guide shell 5 is fixedlyed connected with control lever 8, and the described guide shell 5 of described control lever 8 controls slides before and after described dividing plate 18 outer walls.

As preferably, described coal dust clasfficiator 15 is 2 to 4, flaring angle be 15 degree to 60 degree, the fiery face inclination angle of described guide shell 5 is that 30 degree are to 60 degree.

As preferably, the structure of described biconial enlarging 2 is the relative taper enlargings in inwall two sides.

Therefore, the utlity model has characteristics such as rational in infrastructure, easy to use, after especially the mozzle 12 of mounting strap enlarging, biconial enlarging 2, coal dust clasfficiator 15 and a wind are shunted tube 6 in windbend pipe 1 of burner.Improved the coal powder density of recirculating zone, center, just the easier local reduction atmosphere zone that occurs; Its momentum is big more, and its inertia of the easier dependence of its pulverized coal particle keeps stroke, and the time that stops in the reducing zone is longer, easy more ignition of coal dust and steady combustion, and the generation of Nox all can effectively be controlled in this two aspect.Owing to realize the coal dust classification, heat required when making coal powder ignition has been realized fuel-economizing or has been saved other igniting energy much smaller than the burner that does not carry out classification; Owing to be provided with the guide shell 5 that slides before and after carrying out along dividing plate 18, can regulate the air quantity of front and back secondary wind, thereby realize the minimizing of coking on the water-cooling wall 20.

Description of drawings

Accompanying drawing 1 is a kind of structural representation of the present utility model;

The specific embodiment

Below by embodiment, and in conjunction with the accompanying drawings, the technical solution of the utility model is described in further detail.

Consult Fig. 1, present embodiment comprises windbend pipe 1 one time, be positioned at the igniter 3 at windbend pipe 1 a straight section part center, be positioned at the radian at windbend pipe 1 a sweep center and the mozzle 12 of the band enlarging that windbend pipe 1 sweep adapts, be positioned at the biconial enlarging 2 behind the mozzle 12, be arranged at a wind shunting tube 6 behind the coal dust clasfficiator 15, interior wind passage 14, an outer wind passage 13, the enlarging of mozzle 12 is positioned at the import of a windbend pipe 1, the fiery dorsad side of the enlarging of coal dust clasfficiator 15, the minimum place of the internal diameter of biconial enlarging 2 is greater than the enlarging diameter maximum of coal dust clasfficiator 15, and the diameter of a wind shunting tube 6 is less than the minimum place of the diameter of coal dust clasfficiator 15.15,2 the coal dust clasfficiators 15 of 2 coal dust clasfficiators that are provided with that are positioned at after the biconial enlarging 2 reduce successively towards fiery side direction diameter, and the diameter of the enlarging maximum of a back coal dust clasfficiator 15 is less than the minimum place of the diameter of previous coal dust clasfficiator 15.Secondary air duct 10 and outer secondary air duct 17 in the outside of a windbend pipe 1 has, before being divided into by the dividing plates 18 of tubular in the described outer secondary air duct 17 secondary air duct 9 with after secondary air duct 11.Be provided with cyclone 4 in a wind passage 13 outside, 9 are provided with cyclone 16 in preceding secondary air duct, and the air inlet place of secondary air duct 17 is provided with air door baffle plate 7 outside.Dividing plate 18 be outside equipped with can slide along dividing plate 18 front and back the guide shell 5 of band enlarging, the enlarging of guide shell 5 is towards fiery side, guide shell 5 is fixedlyed connected with control lever 8, the slip before and after dividing plate 18 outer walls of control lever 8 control guide shells 5.

In use, after the coal dust air of sending here from wind pulverized coal feed pipe enters windbend pipe 1, diversed pipe 12 carries out preliminary classification, concentrates, be interior dense outer light two crural ring shape air-flows with breeze airflow by inertial separation through biconial enlarging 2 and coal dust clasfficiator 15 again, at last by shunting tube 6, breeze airflow is divided into an interior wind 14 and outer wind 13 two parts, and an interior wind sprays into burner hearth 19 after nozzles 21 are lighted.Spray into the center recirculating zone core of position over against burner.Because an interior wind breeze airflow is along the increase of its flow process, its coal powder density near center line K is more and more denseer.Coal powder density is high more, just the easier local reduction atmosphere zone that occurs; Its momentum is big more, and its inertia of the easier dependence of its pulverized coal particle keeps stroke, and the time that stops in the reducing zone is longer, easy more ignition of coal dust and steady combustion, and the generation of burning type Nox all can effectively be controlled in this two aspect.Make outer wind rotation through cyclone 4, form the recirculating zone, center in the central area of burner.Because dense outer light two parts in a time wind has been divided into, thereby formed fractional combustion, realized the discharging of low Nox, discharge when high at Nox, can pass through damper baffle plate 7, the flow of swirl secondary air in the secondary air duct 9 before reducing, the flow of direct current secondary wind in the secondary air duct 11 after increasing, swirl secondary air and the mixed of a wind are weakened, so just can reduce Nox; Because realize the coal dust classification, heat required when making coal powder ignition significantly reduces, thereby realized fuel-economizing or saved other igniting energy; Simultaneously,, be increased in the coal dust amount of the recirculating zone, center of high temperature, prolong coal dust, help the after-flame of coal dust, can realize the smooth combustion of different quality coals in the time of staying of the recirculating zone, center of high temperature owing to recirculating zone, center temperature height.When using the coal of coking trend, removable shunting tube 5 is to close water-cooling wall 20 sides, and also removable simultaneously baffle plate 7 is secondary wind 9 sides forward, the speed and the air quantity of back secondary wind 11 are increased, water-cooling wall is purged, form the wind screen simultaneously, avoid pulverized coal particle collision water-cooling wall.

The utility model mainly is suitable for the burner as big-and-middle-sized coal-burning boiler.Many parameters in the utility model all can change as the flaring angle of biconial enlarging, the flaring angle of coal dust clasfficiator and the parameters such as angle at fiery face inclination angle, can adjust accordingly different coals and operating mode.This burner has lower Nox discharge capacity, can realize combustion with reduced pollutants.Simultaneously, the steady right property of the underload of this burner is strong, can conveniently stably burner be regulated under the situation of operating mode and coal variation.

Claims (9)

1. A staged combustion swirl pulverized coal burner, comprising a primary air elbow (1), an igniter (3) positioned at the center of the straight section of the primary air elbow (1), characterized in that: it also includes a The radian of the center of the curved part of the primary air elbow (1) is adapted to the curved part of the primary air elbow (1) with a flared diversion pipe (12), and a double Conical flaring (2), a pulverized coal classifier (15) with flaring behind the double conical flaring (2), and a primary air splitter arranged behind the pulverized coal classifier (15) (6), the inner primary air channel (14), the outer primary air channel (13), the flaring of the guide pipe (12) is located at the air inlet of the primary air elbow (1), and the pulverized coal is classified The flaring of the device (15) faces away from the fire side, and the minimum inner diameter of the biconical flare (2) is larger than the largest flaring diameter of the pulverized coal classifier (15), and the primary air splitter ( 6) The diameter is equal to or smaller than the minimum diameter of the pulverized coal classifier (15). 2. The staged combustion swirl pulverized coal burner according to claim 1, characterized in that: said primary air elbow (1) is provided with a plurality of pulverized coal classifiers (15) along the central line (K) , the diameters of a plurality of pulverized coal classifiers (15) decrease successively toward the fire side, and the diameter of the largest flared part of the latter pulverized coal classifier (15) is equal to or smaller than the smallest diameter of the previous pulverized coal classifier (15) place. 3. The staged combustion swirl pulverized coal burner according to claim 1 or 2, characterized in that: there are inner secondary air passages (10) and outer secondary air ducts (10) on the outside of the primary air elbow (1). Road (17), the outer secondary air passage (17) is separated into a front secondary air passage (9) and a rear secondary air passage (11) by a cylindrical partition (18). 4. The staged combustion swirl pulverized coal burner according to claim 3, characterized in that: said outer primary air passage (13) is provided with a swirler (4), said front secondary air passage (9) A cyclone (16) is provided, and an air door baffle (7) is provided at the air inlet of the outer secondary air duct (17). 5. The staged combustion swirl pulverized coal burner according to claim 3, characterized in that: outside the said partition (18), there is a belt flare that can slide back and forth along the partition (18). The guide tube (5), the flare of the guide tube (5) faces the fire side, the guide tube (5) is fixedly connected with the control rod (8), and the control rod (8) controls the The guide tube (5) slides back and forth along the outer wall of the partition (18). 6. The staged combustion swirl pulverized coal burner according to claim 4, characterized in that: outside the said partition (18), there is a belt flare that can slide back and forth along the partition (18). The guide tube (5), the flare of the guide tube (5) faces the fire side, the guide tube (5) is fixedly connected with the control rod (8), and the control rod (8) controls the The guide tube (5) slides back and forth along the outer wall of the partition (18). 7. The staged combustion swirl pulverized coal burner according to claim 5, characterized in that: there are 2 to 4 said pulverized coal classifiers (15), the flaring angle is 15 degrees to 60 degrees, and the guide The fire surface inclination angle of flow tube (5) is 30 degree to 60 degree. 8. The staged combustion swirl pulverized coal burner according to claim 6, characterized in that: there are 2 to 4 pulverized coal classifiers (15), the flaring angle is 15 degrees to 60 degrees, and the guide The fire surface inclination angle of flow tube (5) is 30 degree to 60 degree. 9. The staged combustion swirling pulverized coal burner according to claim 1, characterized in that: the structure of the double-cone flare (2) is a conical flare with two opposite sides of the inner wall.