CN203099814U - a pulverized coal burner - Google Patents

Abstract

The utility model discloses a pulverized coal burner. A secondary bellow is divided into an inner secondary air chamber and an outer secondary air chamber. An inner secondary air pipe is arranged in the inner secondary air chamber. A primary air pipe is arranged in the inner secondary air pipe. A central pipe is arranged in the primary air pipe. A light oil gun and an ignition electrode are mounted in the central pipe. A group of vanes are further annularly disposed in the inner secondary air chamber. The vanes blow air flow of the inner secondary air chamber into an inner secondary air duct between the inner secondary air pipe and the primary air pipe. A pre-combustion chamber is wrapped in the outer secondary air chamber. A swirler is disposed in the primary air pipe. A combustion stabilizer is disposed at an outlet of the primary air pipe. The pulverized coal burner is fast in temperature rising, low in operation cost, low in NOx emission, even in pulverized coal distribution, thorough in pulverized coal combustion and the like.

Description

a pulverized coal burner

technical field

The utility model relates to a pulverized coal burner, in particular to a swirl burner suitable for use in industrial pulverized coal boilers with stable combustion and low NO _x emission.

technical background

my country's energy structure is still dominated by coal, and industrial coal-fired boilers account for a large proportion of energy consumption. Most of the existing coal-fired industrial boilers are layer-fired boilers with chain grates, and the operating efficiency is low. The pulverized coal industrial boiler fired in the suspension chamber has a very high energy utilization rate. In traditional pulverized coal combustion devices, it is mostly used in large boilers for power generation boilers, and cannot be directly used in small and medium-sized industrial pulverized coal boilers. The development of a pulverized coal burner suitable for small and medium-sized industrial pulverized coal boilers that can stably and efficiently organize pulverized coal combustion and has low _NOx emissions is in line with the national energy policy and is also urgently needed by the market.

Contents of the invention

In view of the above problems, the utility model aims to solve the above defects in the prior art, and aims to provide a pulverized coal burner suitable for industrial boilers with stable combustion, high efficiency and low _NOx emissions.

To achieve the above object, the utility model takes the following technical solutions:

A pulverized coal burner, comprising a secondary air box, characterized in that the secondary air box is divided into an inner secondary air chamber and an outer secondary air chamber; the inner secondary air chamber is provided with a secondary air The air inlet, the inner secondary air duct is provided in the inner secondary air duct, the primary air duct is provided in the inner secondary air duct, the central pipe is provided in the primary air duct, and the central pipe It is equipped with a light oil gun and an ignition electrode; the inner secondary air chamber is also provided with a set of annular blades, and the blades blow the airflow of the inner secondary air chamber into the inner secondary air pipe and the primary air The inner secondary air channel between the pipes; the outlet end of the inner secondary air channel is connected to the pre-combustion chamber; the pre-combustion chamber is wrapped in the outer secondary air chamber; the inner secondary air The room and the external secondary air chamber are communicated through the damper; the primary air pipe is provided with a swirler; the outlet of the primary air pipe is provided with a burner; the light oil gun is connected to an oil pump; The ignition electrode is connected to the ignition transformer.

Because the utility model adopts the above-mentioned body scheme, it has the following advantages:

1. Because the utility model has a pre-combustion chamber, the combustion space is small, and the temperature rises quickly. It only needs a little oil and a short time to ignite the pulverized coal, realizes ignition with less oil or less oil, and effectively reduces operating costs.

2. The utility model separates the secondary air box into inner and outer air chambers, forms double air ducts, and realizes graded air supply, so that pulverized coal undergoes oxygen-deficient combustion in the pre-combustion chamber, so that the combustion environment is in a reducing atmosphere, which can effectively reduce NO _x Generate, achieve low _NOx emissions, and meet environmental protection requirements.

3. The inner secondary air chamber of the utility model is provided with blades, so that the passing airflow generates a swirling flow. The swirling flow is conducive to the generation of the recirculation zone, the entrainment of high-temperature flue gas, the rapid ignition of pulverized coal fuel, and the rapid start and stop of the boiler.

4. The uniform distribution of pulverized coal in the primary air flow is the key to stable combustion. The utility model is provided with a swirler in the primary air duct, so that the passing primary air pulverized coal airflow is rotated, thereby eliminating the uneven circumferential distribution of pulverized coal caused by the turning of the primary air duct, but at the same time producing radial airflow due to centrifugal force. uneven distribution.

5. The pre-combustion chamber of the utility model is covered in the outer secondary air chamber, which can realize the cooling of the pre-combustion chamber and prevent the pre-combustion chamber from coking and being burned out. The outlet of the external secondary air is set outside the outlet of the pre-combustion chamber, and the external secondary air cuts into the flame ejected from the burner in the boiler furnace in the form of direct flow, so as to supplement the oxygen required for the complete combustion of pulverized coal and realize the complete combustion of pulverized coal fuel. combustion.

As a further improvement of the utility model, the damper is adjusted through a damper pull rod.

As a further improvement of the utility model, the pre-combustion chamber includes an inlet expanding cone section, a middle cylinder and an outlet contracting section, and the outlet is smaller than the inlet, so that the flame in the pre-chamber is rotated and ejected at a high speed, thus taking away the pre-combustion chamber. The ash in the combustion chamber is self-cleaning. The cone angle of the inlet expansion cone of the pre-combustion chamber is 15°-20°, and the cone angle of the outlet contraction section is 20°-30°.

As a further improvement of the utility model, the light oil gun and the ignition electrode can realize automatic ignition through program control. The light oil gun and the ignition electrode can automatically advance and retreat through program control, automatically extend into the furnace when ignited, and automatically retreat into the burner center tube after ignition is completed.

As a further improvement of the utility model, the angle of inclination of the blades is adjustable, and the adjustment is made through the handle mechanism to make the passing air flow generate swirling flows of different intensities.

As a further improvement of the utility model, the burner is in the shape of an expanding cone, and the inlet end is provided with a gear ring, so that the coarser particles are refracted into the center of the flame due to the blocking of the teeth of the burner, and the finer coal powder The particles gather in the vortex area formed behind the teeth, so that the pulverized coal particles have a better distribution in the flame area, thereby realizing the temperature combustion of the pulverized coal.

Description of drawings

Fig. 1 is the structural representation of the utility model.

Fig. 2 is a view along the line A-A of Fig. 1 .

Fig. 3 is a B-B arrow view of Fig. 1 .

In the figure: 1. Ignition transformer, 2. Ignition electrode, 3. Center tube, 4. Primary air pipe, 5. Outer secondary air door adjustment rod, 6. Blade, 7. Inner secondary air chamber, 8. Secondary air Inlet, 9. Inner secondary air pipe, 10. Outer secondary air door, 11. Outer secondary air chamber, 12. Pre-combustion chamber, 13. Outer secondary air outlet, 14. Stabilizer, 15. Light oil gun , 16, primary air cyclone, 17, secondary air blade adjustment handle, 18, oil pump, 19-primary air duct, 20-inner secondary air duct, 20-gear ring, 1201-inlet expansion cone section, 1202- Middle cylinder, 1203-exit shrinkage section, 1401-gear ring.

Detailed ways

In order to describe the structure and features of the present utility model in detail, the following preferred embodiments are given and illustrated with accompanying drawings.

As shown in Figure 1, a pulverized coal burner of the present utility model includes a secondary air box, and the secondary air box is divided into an inner secondary air chamber 7 and an outer secondary air chamber 11; The secondary air chamber 7 is provided with a secondary air inlet 8, the inner secondary air chamber 7 is provided with an inner secondary air duct 9, and the inner secondary air duct 9 is provided with a primary air duct 4, The primary air duct 4 is provided with a central pipe 3, and the central pipe 3 is equipped with a light oil gun 15 and an ignition electrode 2; the inner secondary air chamber 7 is also provided with a group of annularly arranged blades 6, The blade 6 blows the airflow of the inner secondary air chamber 7 into the inner secondary air duct 20 between the inner secondary air duct 9 and the primary air duct 4; the outlet of the inner secondary air duct 9 The end is connected to the pre-chamber 12; the pre-chamber 12 is wrapped in the outer secondary air chamber 11; the inner secondary air chamber 7 and the outer secondary air chamber 11 communicate through the damper 10, so The damper 10 is adjusted through the damper pull rod 5; the primary air pipe 4 is provided with a swirler 16; the outlet of the primary air pipe 4 is provided with a burner 14; the light oil gun 15 is connected to An oil pump 18; the ignition electrode 2 is connected to the ignition transformer 1.

The air intake speed of the damper 10 is adjustable, and is adjusted through the damper pull rod 5 .

The pre-chamber 12 includes an inlet expanding cone section 1201, a middle cylinder 1202 and an outlet constricting section 1203, and the outlet is smaller than the inlet. The cone angle of the inlet expanding cone section 1201 of the pre-chamber 12 is 15°-20°, and the cone angle of the outlet constricting section 1203 is 20°-30°.

The light oil gun 15 and the ignition electrode 2 realize automatic ignition through program control. The light oil gun 15 and the ignition electrode 2 realize automatic advance and retreat through program control, and automatically extend into the furnace when ignited; automatically retreat into the central tube 3 of the burner after the ignition is completed.

Referring to FIG. 2 , the angle of inclination of the blade 6 is adjustable, and is adjusted through the handle mechanism 17 .

Referring to FIG. 3 , the burner 14 is in the shape of an expanding cone, and the inlet end is provided with a gear ring 1401 .

When the utility model is installed, the entire burner is flanged to the burner mounting seat of the boiler, the primary air pipe 4 is connected to the pulverized coal conveying pipe (not shown in Fig. 1 ), and the secondary air inlet 8 is connected to a A blower (not shown in Figure 1) is connected.

The working process of the present utility model is as follows:

First, turn on the boiler induced draft fan and blower for pre-purging, and adjust the fan to the required furnace negative pressure. Start the oil pump 18 and the ignition transformer 1, so that the fuel is sprayed out through the nozzle of the light oil gun 15 and ignited by the ignition electrode 2. When starting the oil pump 18 and the ignition transformer 1, the light oil gun 15 and the ignition electrode 2 stretch out from the center pipe 3 automatically. After the fuel oil is ignited for 10 seconds, start the pulverized coal conveying device (not shown in Figure 1), and the pulverized coal is transported by the primary air through the primary air duct 19 between the primary air pipe 4 and the central pipe 3 and passes through the cyclone 16 is ejected at stabilizer 14 places after generating rotation, and is ignited by fuel oil flame. At the same time, the secondary air enters from the secondary air inlet 8, and is divided into two internal and external secondary air flows through the two separated air chambers. The internal secondary air is rotated by the blades 6 and enters the pre-combustion through the internal secondary air duct 20. Chamber 12 participates in the combustion of pulverized coal. The primary air and internal secondary air are not enough to support the complete combustion of pulverized coal in the pre-combustion chamber 12, so that it is in an oxygen-poor reducing environment, which effectively suppresses the generation of _NOx . After the pulverized coal is ignited and co-combusted with the fuel oil for 10 to 30 seconds, turn off the light oil gun and burn completely by the pulverized coal. The light oil gun and ignition electrode are automatically retracted into the center tube to prevent them from being burned out. Both the primary air and the internal secondary air are swirling. At the same time, the pre-chamber 12 adopts an inlet and an outlet with a cone angle, and the outlet is smaller than the inlet, so that the flame in the pre-chamber 12 is rotated and ejected at a high speed, thereby taking away the pre-combustion chamber. The ash in the combustion chamber 12 realizes self-cleaning. The outer secondary air chamber 11 is wrapped outside the pre-combustion chamber 12, and the external secondary air can cool the pre-combustion chamber to prevent the pre-combustion chamber from coking and being burned out. The external secondary air outlet 13 is set outside the outlet of the pre-combustion chamber 12, and the external secondary air cuts into the flame ejected from the burner in the boiler furnace in the form of direct flow, so as to supplement the oxygen required for the complete combustion of pulverized coal and realize the combustion of pulverized coal fuel. of complete combustion.

It should be understood that: the above-mentioned embodiment is only an illustration of the utility model, rather than a limitation of the utility model, and any utility model creation within the scope of the essential spirit of the utility model all falls within the protection scope of the utility model .

Claims (8)

1. a coal burner comprises secondary air box, it is characterized in that described secondary air box is separated into interior secondary air chamber (7) and outer secondary air chamber (11); Secondary air chamber (7) is provided with secondary wind air inlet (8) in described, be provided with interior secondary air channel (9) in the secondary air chamber (7) in described, be provided with an airduct (4) in the secondary air channel (9) in described, be provided with central tube (3) in the described airduct (4), light oil rifle (15) and ignitor (2) are housed in the described central tube (3); Also be provided with the blade (6) that one group of annular is provided with in described in the secondary air chamber (7), described blade (6) with the air-flow of interior secondary air chamber (7) be blown into described in interior secondary air duct (20) between secondary air channel (9) and the airduct (4); The port of export of secondary air duct (9) connects precombustion chamber (12) in described; Described precombustion chamber (12) is wrapped in the described outer secondary air chamber (11); Secondary air chamber (7) and outer secondary air chamber (11) are by air door (10) UNICOM in described; Be provided with a cyclone (16) in the described airduct (4); The exit of a described airduct (4) is provided with stabilizer (14); Described light oil rifle (15) connects an oil pump (18); Described ignitor (2) connects ignition transformer (1).

2. a kind of coal burner as claimed in claim 1 is characterized in that described air door (10) regulates by choker rod (5).

3. a kind of coal burner as claimed in claim 1 it is characterized in that described precombustion chamber (12) comprises import reamer section (1201), middle cylinder (1202) and outlet contraction section (1203), and outlet is less than import.

4. a kind of coal burner as claimed in claim 3, the cone angle that it is characterized in that the import reamer section (1201) of described precombustion chamber (12) is 15 ° ~ 20 °, the cone angle of outlet contraction section (1203) is 20 ° ~ 30 °.

5. a kind of coal burner as claimed in claim 1 is characterized in that described light oil rifle (15) and ignitor (2) are by programme-control realization igniting automatically.

6. a kind of coal burner as claimed in claim 5 is characterized in that described light oil rifle (15) and ignitor (2) by the automatic advance and retreat of programme-control realization, put in burner hearth automatically during igniting; After finishing, igniting is retracted into automatically in the central tube (3) of burner.

7. a kind of coal burner as claimed in claim 1 is characterized in that described blade (6) tilt adjustable, and regulates by handle mechanism (17).

8. as any one described a kind of coal burner of claim 1-7, it is characterized in that described stabilizer (14) is reamer shape, entrance point is provided with ring gear (1401).

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