Common faults and treatment in cement making process chapter two

There are many problems in vertical mill operation, as long as the corresponding treatment measures well done, all failure can be prevent, or avoid, or minimize losses.

1.1.3 Water spray

(1) Water spray is too small; the material layer is not easy to stabilize which causes vibration.

Treatment measures: increase the amount of water.

(2) the amount of water is too large to be greater than 3% with the moisture material contained, the material layer is not easy to stabilize, material layer is too thick, the "plow material" phenomenon will shows up and cause vibration.

Treatment measures: quickly reduce or shut down the water until the material layer is stabilized.

(3) Lack of water. The stability of the material layer is mainly controlled by the humidity of the raw materials. Especially sandstone is used as the siliceous material and the iron ore is used as the iron correction raw material, because the moisture content is low and the humidity is small. Without waste heat power generation, inlet wind temperature is high (about 300 ℃) when lack of water, the stability of the material layer is destroyed and causing the mill vibration.

Treatment measures: quickly find the cause of water lack and given appropriate amount of water.

 1.1.4 Matching of the rollers pressures

Relative to the material size, fragility and moisture, the amount of feed and the roller pressure is proportional. In general, the feed volume is large, the roller pressure is large, and vice versa; but unreasonable roller pressure matching can also cause vibration, the roll relative to the feeding quantity is too high, will cause the material layer thin while then cause vibration.

Treatment measures: given the appropriate roller pressure depend on experience of daily production.

1.1.5 Full grinding

Full grinding caused by vertical mill are generally: feed volume is too large, the separator speeds too fast, the internal circulation is too large, low roll pressure, the cycle load is too large, or a small amount of ventilation, resulting in excessive powder which is more than the carrying capacity of air, and finally material will be buried by the roller causing vibration.

Treatment measures: appropriate to reduce the separator speed, increase the roll pressure, and increase the amount of air, make mill conditions stable.