CN2603295Y - Central powder fed vortex coal powder burner - Google Patents

Abstract

The utility model relates to a central feeding rotary flow coal powder inflamer, which belongs to inflamer particularly to an inflamer which burns coal powder. Center of an inflamer shell (13) is vertically provided a primary wind tube (8). One end of the primary wind tube (8) in the inflamer shell (13) is provided with a burner port (2). A powder conveying tube (9) is connected with the primary wind tube (8). A tapered separating ring (3) is arranged in the primary wind tube (8). Small end of the separating ring (3) directs to the burner port (2). A plurality of separating ring (3) can also be arranged in the primary wind tube (8) and along a central line K. Diameter of the separating rings directing to the burner port (2) reduces in turn. The utility model is a rotary flow coal powder inflamer with high combustion efficiency and low NOx emission.

Description

A kind of center powder-feeding cyclone burner for pulverized coal

Technical field: the utility model relates to a kind of burner, and particularly a kind of is the burner of fuel with the coal dust.

Background technology: nitrogen oxide (NOx) is the primary pollution source that causes atmosphere pollution, and it destroys ecological environment except forming acid rain, can also form photochemical fog, harm humans health.Coal burning is one of main source of NOx, pollute in order to control serious day by day NOx, State Bureau of Environmental Protection has issued " thermal power plant's atmosphere pollutants emission standards " (GB13223-26) on March 7th, 1996, has stipulated clearly in the standard that 300MW and above unit dry ash extraction coal-powder boiler NOx discharge capacity must not surpass 650mg/m ³If, do not take the low NOx drainage measure, be difficult to satisfy the emission request of NOx." The Law of the People's Republic of China on the Prevention and Control of Atmospheric Pollution " carried out on September 1st, 2000 also proposed the requirement to the NOx control emission.NOx control mainly contains two kinds of approach, and the one, adopt the generation of low NO technology minimizing NOx, the 2nd, from flue gas, remove NOx.Under the present economic level of China, the former is comparatively effective, economically viable method; The latter's subject matter is to invest too highly, is not suitable for the national conditions of China.Turbulent burner occupies certain ratio at China's station boiler and other coal dust application.Adopt the large coal powder boiler of turbulent burner that its unique advantage is arranged: first-selection can avoid adopting the thermal deviation in the superheater district that the DC burner corner tangential firing produces; Next is that the burner hearth shape is not had strict requirement, needn't be necessarily near square, and this brings great convenience for the layout of afterbody convection heating surface.Turbulent burner relies on high temperature recirculation zone as stable thermal source, make breeze airflow timely the smooth combustion of fighting, common turbulent burner primary and secondary air is mixed strong, the temperature peak height, the NOx growing amount is big.Along with China's unit day by day to the development of big capacity, the development of spiral-flow powdered coal burning technology has been proposed urgent requirement.Therefore, research low NOx cyclone pulverized coal combustion all is that crucial meaning is arranged to the development of China's power industry and whole national economy.

The utility model content: for solving is the too high problem of burner NOx discharge capacity of fuel with the coal dust at present, and the utility model is developed a kind of center powder-feeding cyclone burner for pulverized coal.The purpose of this utility model realizes in the following manner: be vertically arranged with one time airduct 8 in the center of burner shell 13, the end that airduct 8 is positioned at burner shell 13 is nozzles 2, pulverized coal feed pipe 9 is connected with an airduct 8, be provided with the eseparation ring 3 of conical ring in an airduct 8, the small end of eseparation ring 3 is towards nozzles 2.The utility model can also be provided with a plurality of eseparation rings 3 along center line K in an airduct 8, a plurality of eseparation rings 3 reduce successively towards nozzles 2 direction diameters.The main points that the utility model is created are: central tube is not set, and airduct 8 of burner is positioned at the center of burner, and taper eseparation ring 3 is installed in airduct of burner.After the coal dust air of sending here from wind pulverized coal feed pipe flowed into taper eseparation ring 3 in wind passage of burner 8, coal dust was concentrated in the center of burner, sprayed into burner hearth 1 by middle the heart channel of Hang-Shaoyin nozzles 2 of burner.Spray into the center recirculating zone core of position over against burner.The coal dust amount of therefore passing through the recirculating zone, center increases, the crossing time of coal dust prolongs, coal dust is burnt under reducing atmosphere, prolong the time of staying of coal dust in reducing atmosphere, can control burning type NOx, the recirculating zone, center is hypoxemia reducing atmosphere district, therefore, can effectively control the formation of burning type NOx.Secondary wind enters separated into two parts behind the burner by secondary air duct 11, they enter burner hearth 1 through secondary air duct 7 in the outer secondary air duct 6 of burner, the burner respectively, the aperture of damper baffle plate 10,12, can change the ratio of inside and outside swirl secondary air, make the rotation of secondary wind by outer cyclone 4, interior cyclone 5, form the recirculating zone, center in the central area of burner.Because secondary wind has been divided into inside and outside two parts, thereby has formed fractional combustion, combines to powder with the center, has realized low NOx drainage.Because recirculating zone, center temperature height, the initial stage of coal dust firing is the dynamic combustion device, is increased in the coal dust amount of the recirculating zone, center of high temperature, prolong the time of staying of coal dust in the recirculating zone, center of high temperature, the after-flame that helps coal dust, therefore, the utility model also can be realized higher efficiency of combustion.The utility model is a kind of swirling pulverized coal combustion device of efficient, low NOx drainage.

Description of drawings: Fig. 1 is a structural representation of the present utility model.

The specific embodiment: consult Fig. 1, present embodiment is made up of burner shell 13, body of heater 1, nozzles 2, eseparation ring 3, outer cyclone 4, interior cyclone 5, airduct 8, pulverized coal feed pipe 9, interior air door baffle plate 10, an outer damper plate 12.Burner shell 13 is connected with body of heater 1.An airduct 8 is arranged on the center of burner shell 13, and the end that airduct 8 is positioned at burner shell 13 is nozzles 2, and pulverized coal feed pipe 9 is arranged on the outside of burner shell 13, and pulverized coal feed pipe 9 is connected with an airduct 8.3, three eseparation rings 3 of eseparation ring that are provided with three tapers in an airduct 8 reduce successively towards nozzles 2 direction diameters, and the small end of each eseparation ring 3 is towards nozzles 2.In the outside of an airduct 8 secondary air duct 11 is arranged, the dividing plate 11-1 by tubular in the secondary air duct 11 is divided into interior secondary air duct 7 and outer secondary air duct 6.In in interior secondary air duct 7 and outer secondary air duct 6, being respectively arranged with cyclone 5 and outside cyclone 4, interior secondary air duct 7 with outside the air inlet place of secondary air duct 6 also be provided with in air door baffle plate 10 with outside damper plate 12.Secondary wind part-structure of the present utility model can be varied, as secondary wind in can adopting is the form of eddy flow, outer secondary wind is direct current, adjust swirl strength by the ratio of adjusting inside and outside secondary wind, it is eddy flow that the size of recirculating zone, change center also can adopt inside and outside secondary wind, swirl strength is adjusted in angle by regulating outer secondary wind cyclone or the position in the secondary air channel outside, changes the size of recirculating zone, center.

Claims (4)

1, a kind of center powder-feeding cyclone burner for pulverized coal, it is characterized in that being vertically arranged with an airduct (8) in the center of burner shell (13), the end that an airduct (8) is positioned at burner shell (13) is nozzles (2), pulverized coal feed pipe (9) is connected with an airduct (8), be provided with the eseparation ring (3) of conical ring in an airduct (8), the small end of eseparation ring (3) is towards nozzles (2).

2, a kind of center according to claim 1 powder-feeding cyclone burner for pulverized coal is characterized in that being provided with a plurality of eseparation rings (3) along center line K in an airduct (8), and a plurality of eseparation rings (3) reduce successively towards nozzles (2) direction diameter.

3, a kind of center according to claim 1 and 2 powder-feeding cyclone burner for pulverized coal, it is characterized in that in the outside of an airduct (8) secondary air duct (11) being arranged, the dividing plate (11-1) by tubular in the secondary air duct (11) is divided into interior secondary air duct (7) and outer secondary air duct (6).

4, a kind of center according to claim 3 powder-feeding cyclone burner for pulverized coal, it is characterized in that interior secondary air duct (7) and outside be respectively arranged with in the secondary air duct (6) interior cyclone (5) and outside cyclone (4), interior secondary air duct (7) and outside the air inlet place of secondary air duct (6) also be provided with in air door baffle plate (10) and outside damper plate (12).

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