How should the preheater system be adjusted?
Date：2019-09-04 16:11 Source：cementepcViews:
The operation of predecomposing kiln should be both before and after, the predecomposing system should be considered in combination with the firing of kiln head, and the fast turning rate should be improved.
1.Adjustment of the spreader Angle
The spreader is generally placed at the bottom of the discharge tube of the cyclone drum.Experience tells us that the material through the flap valve is a group, a share.This kind of lump or crudate material, the air current cannot take up but directly falls into the cyclone tube to cause the short circuit.The function of the sputtering board is to spread out the cluster-like or crud-like materials so that the materials are evenly dispersed into the airflow of the inlet pipe of the next level cyclone tube.In the preheater system, the heat transfer between airflow and evenly dispersed materials is mainly carried out in the pipeline.
Although the structure of the preheater system is quite different, the following set of data are basically the same.In general, the difference between the inlet and outlet gas temperature of the cyclone tube is mostly about 20℃, and the material temperature out of the cyclone tube is about 10℃ lower than the outlet gas temperature.This shows that the heat exchange between material and gas in the cyclone tube is very little.
Therefore, the extent to which the spreading board spreads the material determines the heating area of raw materials and directly affects the heat exchange efficiency.The spreader Angle is too small, and the dispersion effect of materials is not good.On the contrary, it is easy to be burned out, and when the bulk material collapses, it is easy to produce blockage due to the small section area of pipeline.So the production debugging period should be repeatedly adjusted its Angle.At the same time, pay attention to observe the temperature difference between the inlet and outlet of the cyclone cylinder at all levels until it is adjusted to the best position.
2.Adjustment of balance bar Angle and counterweight of plate flip valve
The blanking pipe of each stage cyclone tube in the preheater system is provided with a flap valve.In general, the higher the swing frequency of the flap valve, the more uniform the material in the intake pipe of the next stage cyclone tube, the less the possibility of air short-circuit.The swing flexibility of the flip valve mainly depends on the Angle of the balance bar and its counterweight.According to experience, the position of the tilting valve balance bar should be below the horizontal line, and the Angle between the horizontal line is less than 30 degrees.Someone has done the calculation, the best can be adjusted to about 15 degrees.At this time, the displacement of center of gravity line of balance bar and counterweight is very small, and the space between center of gravity and valve plate drive shaft increases with the increase of valve plate opening.Torque increases, the time required for disc resetting is shortened, and the flexibility of valve swing can be improved.As for counterweight, should be in the cold state when the initial adjustment, adjustment to lift the balance bar with your fingers gently up, a release on the balance bar reset.In hot state, it only needs to make micro adjustment to individual tilting valve.
3 compressed air blocking purge device purge time adjustment
In the preheater system, according to its position, internal temperature and material performance, each stage cyclone cylinder is usually equipped with 1 ~ 3 circles of compressed air blocking and scavenging device in the cone.Air pressure is generally controlled at 0.6-0.8mpa.When the system is running normally, the computer will perform automatic purging regularly.Purge time can be set manually as needed.Generally, the whole system will be purged every 20min or so.Sweep 3 -- 5s per cyclone drum.When the pressure fluctuation of the preheater system is large or abnormal conditions such as material collapse frequently occur, the purging time interval can be shortened at any time, or even it can be fixed on a first-stage cyclone drum for a long time of continuous purging.Of course, there are no abnormal circumstances, should not take this method of purging.Because blowing a lot of cold air will destroy the normal thermal system of the system, reduce the thermal efficiency and increase the thermal consumption of the system.
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