Four - channel pulverized coal burner structureDate: 2019-07-18 Views:
The rotary kiln pulverized coal burner has been developed from the center to three air ducts, four air ducts and five air ducts burning two or three fuels.The more ducts, the better the performance, but the more complex the structure.The fine performance of the four air pulverized coal burner - secondary air consumption can be generally reduced to 5% ~ 7%, even 3% ~ 4%, can burn high quality coal, but also can burn low quality coal, low volatile coal, anthracite, petroleum coke, coal shale, waste tires and household waste.
Structural characteristics of pulverizer
1 outside style with small nozzle spray technology
1.1 the spray area is stable and not easy to deform
The small nozzle is fixed on the annular thick wall of the outer casing with thread connection, evenly distributed along the circumference.Therefore, the jet area is stable and not easy to deform, so as to ensure the regularity and tunability of the external wind jet, and thus make the flame shape reasonable and the performance meet the requirements.
1.2 convenient replacement, saving maintenance costs
The orifice of the small nozzle can be easily replaced once it is worn out, and the heat-resistant steel at the end of the outer casing can still be used, which can save maintenance cost.If other structure is adopted, all heat-resistant steel parts of outer casing end need to be cut and replaced, which wastes expensive heat-resistant steel and increases the maintenance cost.
1.3 the ejection speed can be greatly changed
Generally, there are three sets of small nozzle with different jet aperture, when the need to significantly change the jet speed inch, you can replace the larger or smaller jet aperture nozzle can, do not need to replace the jet burner tube.
1.4 high temperature secondary wind is easy to invade the pulverized coal layer
These small nozzles are uniformly distributed along the circumference, and there is a gap between the two adjacent small nozzles at the root of the outer wind jet, which forms a gap. Secondary wind can easily pass into the pulverized coal layer, providing oxygen to the center of the flame, improving the wind temperature, and accelerating the oxidation combustion.
2. Adopt closed flame hood technology
In multi-channel pulverized coal burners that do not use this technique, the jet flow is always easy to diverge at the root, which is prone to peak temperature.As a result, the temperature in the front is too high, and the temperature in the back is too low.
Close the flame cover is the front part of the outer sleeve of the outside wind extends a distance, which plays the role of closing the flame.Like the hood of a camera.The burner with this technique produces a "necking" at the base of the flame, which not only makes the temperature distribution reasonable, but also extends the service life of the kiln mouth.
3 adopt flame stabilizer technology
Flame stability is very important to ensure the stability of thermal system. The change of flue gas in the kiln and the unevenness of secondary air entering the kiln will affect the stability of the flame.Therefore, the use of flame stabilizer to stabilize the flames of a great role.
4. The center wind
Using special structural measures, from several small holes on the flame stabilizer, adults to simplify the structure and reduce the weight of the jet burning tube, to prevent the jet burning tube bending plays a great role.