CN2372555Y - Pulverized coal burner - Google Patents

Abstract

The utility model relates to a pulverized coal burner belonging to a coal fired boiler device. The utility model is composed of an upper air pipe, a lower air pipe, a reflux space, a suction mouth for external reflux, and a shell body. The utility model is characterized in that the reflux space is formed between both sides of the upper air pipe and an external shell; the shell body which is arranged at the external side of the reflux space is provided with the suction mouth for external reflux. When air flow of pulverized coal is ejected from the upper air pipe and the lower air pipe, negative pressure with the action of entrainment is generated at the root part of a jet nozzle. High temperature flue gas in the burner is sucked into the reflux space through the suction mouth for external reflux so that external reflux is formed, and the flue gas is mixed with air flow of pulverized coal so as to realize heating the pulverized coal. The utility model has the advantages of no abrasion, no burning loss, preferable effect of stable burn for inferior coal and other types of coal which is difficult to burn.

Description

A kind of coal burner

The utility model relates to coal-burning boiler equipment.

There is difficulty and the combustion instability problem of lighting in the boiler combustion colm, and the method for solution is used coal burner that inner flue gas of the stove is refluxed to heat breeze airflow usually, makes breeze airflow can obtain as early as possible that enough heats are lighted and smooth combustion.Existing coal burner is made up of bluff body, secondary bluff body, jet, water diversion part, rectification passage and a return flow line.A bluff body is the isoceles triangle body, and its drift angle limit and two waists are divided into left and right sides two-way with breeze airflow, and the triangle body base is a concave curved surface, forms water diversion part, and the both sides, base angle are the breeze airflow jet; Breeze airflow by the spray of this jet toward secondary bluff body both sides the time, because rectification feeder connection outer side edges and same plane, jet outer side edges place and rectification feeder connection are greater than jet, like this under the breeze airflow jet-action, in the inboard return flow line formation of rectification passage high-temperature flue gas from inside to outside, reflux, reflux in this high-temperature flue gas and flow to the concave curved surface of triangle body through the return flow line, by concave curved surface guiding both sides rectification passage, after the breeze airflow Hybrid Heating, in stove, reach combustion-supporting purpose through the spray of rectification passage.This coal burner exists heavy wear and combustion damage problem because the major part of its secondary bluff body must be placed in the high-temperature flue gas stream during operation, make the burner lost of life, and combustion efficiency reduces.

The purpose of this utility model is, a kind of boiler coal-ash combustor is provided, and it does not does not wear and tear, and not burning not only can make the boiler coal-ash air-flow can obtain enough hot refluxs rapidly, and unburnable coals such as colm are had surely fires effect preferably.

Coal burner of the present utility model is mainly by upcast ventilation pipe, lower air conduit, the backflow space, exteenal reflux suction inlet and housing are formed, main feature is, described upcast ventilation pipe is a square tube, the wall of this square tube is trapezoidally formed piecing together by four, inlet is for being wider than high rectangle, outlet is for tall and big in wide rectangle, the rectangular tube butt joint that this outlet is identical with the cross section, upcast ventilation pipe exports between the two walls outside and the burner housing and forms the backflow space, described lower air conduit is the rectangular tube that the cross section equals the upcast ventilation pipe entrance section, the lower edge of the upper limb of its inlet and upcast ventilation pipe inlet joins, on, the lower air conduit inlet is in same plane, the lower air conduit outlet communicates with the backflow space, has the exteenal reflux suction inlet outside the backflow space on two side bodies, and backflow top of space shell is provided with the secondary air channel of cooling usefulness.

When breeze airflow sprays in stove by this burner under certain pressure, at first be divided into two-way by last lower air conduit, because lower air conduit [4] is short than upcast ventilation pipe [1], following spout [6] is prior to last spout [3] ejection breeze airflow.The flow at high speed of breeze airflow, has the negative pressure of the effect of entrainmenting in following spout [6] jet root generation, this negative pressure makes the pressure in lower air conduit [6] the two side reflux spaces [8] be lower than the pressure of the outer furnace high-temperature flue gas of both sides exteenal reflux suction inlet [9], the swabbing action that this pressure forms makes the furnace high-temperature flue gas form an exteenal reflux from outside to inside by backflow space [8], exteenal reflux enters backflow space [8] and mixes with the primary wind and powder that following spout [6] sprays, thereby has realized the heating to coal dust.Last spout [3] also entrainments effect by the negative pressure that its root sprays, and the negative pressure acting in conjunction that produces with following spout [6] is in the furnace high-temperature flue gas, in backflow space [8] formation exteenal reflux, make breeze airflow rapid fire burns.

When the breeze airflow wind speed of spout ejection instantly is 26m/s, when the coal dust wind speed of last spout is 28m/s, the exteenal reflux flow velocity that enters a backflow space and a wind Hybrid Heating by suction inlet is 6m/s, the ratio m=1.3 of exteenal reflux amount and amount, be equivalent to exteenal reflux rate e=0.3, suck the exteenal reflux temperature-averaging and exceed interior the backflow 100 ℃～200 ℃.Therefore, the coal dust that makes that only leans on the effect of entrainmenting of the root negative pressure of a wind of spout injection up and down just can suck capacity is able to clean-burning exteenal reflux.

Though the last lower air conduit length difference of the utility model burner, spout is the  type and arranges not on same vertical plane up and down, can not only increase suction inlet section and backflow space, and can keep the rigidity of a wind, makes combustion efficiency reach optimum state.

Accompanying drawing is a specific embodiment of the utility model.

Fig. 1 is a profilograph of the present utility model.

Fig. 2 is the right view of Fig. 1.

Fig. 3 is the left view of Fig. 1.

Fig. 4 is the vertical view of Fig. 1.

Fig. 5 is the side view of Fig. 1.

Among Fig. 1-Fig. 5, [1] is upcast ventilation pipe, and this pipe is deformed into tall and big in wide rectangle outlet [3] by being wider than high rectangle entrance [2].[4] be lower air conduit, this pipe is the rectangle tetrahedron, and its inlet [5] equates with the inlet [2] of upcast ventilation pipe [1] and coplane that [6] are the lower air conduit outlet.Form backflow space [8] between upcast ventilation pipe outlet [3] and the shell [7].After upcast ventilation pipe outlet [3] and lower air conduit outlet [6] spray breeze airflow, because [3] entrainment effect with the negative pressure that [6] root produces, produce the high-temperature flue gas exteenal reflux of ecto-entad in backflow space [8], enter backflow space [8] behind the exteenal reflux suction inlet [9] on this exteenal reflux process shell [7], breeze airflow Hybrid Heating with wind tube outlet [3] up and down, [6] ejection, in stove, realize heating through burner outlet [10] spray, reach combustion-supporting effect breeze airflow.[11] be the secondary air channel of cooled enclosure top [12].

Claims (1)

1. boiler coal-ash combustor, by upcast ventilation pipe, lower air conduit, the backflow space, exteenal reflux suction inlet and housing constitute, it is characterized in that, described upcast ventilation pipe is a square tube, the wall of this square tube is trapezoidal to piecing together by four, make the upcast ventilation pipe inlet for being wider than high rectangle, and outlet is for tall and big in wide rectangle, this outlet rectangular tube identical with the cross section joins, described backflow space is respectively by constituting between upcast ventilation pipe outlet both sides outer wall and the burner housing, have the exteenal reflux suction inlet on the housing of the outside, backflow space, the lower edge of described lower air conduit inlet upper limb and upcast ventilation pipe inlet joins, and the lower air conduit outlet communicates with the backflow space.

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