Industry Reports

Operating precautions for slag vertical mill

  • By
  • Mar 14, 2019  UTC+8
  • Views:
  • Tags: slag vertical mill slag grinding mill cost

An important member of the slag vertical mill type slag treatment equipment, the appearance of the slag vertical mill will turn the slag into a treasure, improve the environment and save resources, and is a major contributor to modern environmental protection equipment. So what do we need to pay attention to when operating the slag vertical mill.
vertical roller mill

First, stable a material bed

The slag vertical mill (slag mill and steel slag vertical mill) is ground by a material bed, so a stable layer is essential for the safe operation of the slag vertical mill. Under normal conditions, the thickness of the upper layer of the grinding disc is about 30-60 mm. At this time, the mill runs smoothly, the grinding sound is soft, and the amount of circulating materials inside and outside the mill remains basically unchanged. The material layer is too thin, the mill vibration is large; the material layer is too thick, the mill load is large and the grinding efficiency is low, and severe vibrations are also caused in severe cases.

Second, the balance of materials

In the operation of the slag grinding mill, the feeding amount, the grinding capacity, the airflow conveying amount, the slagging amount or the outer circulation should be in an equilibrium state. In the case of a certain amount of feed, if the grinding capacity is insufficient, a large amount of slag will be caused, and more slag is discharged. At this time, the working pressure of the hydraulic station should be appropriately increased (adjust the relief pressure of the relief valve) In order to enhance the grinding ability or reduce the feeding amount properly; if the grinding ability is too strong, the material layer will gradually thin and eventually cause the mill to vibrate. At this time, the working pressure of the hydraulic station or the feeding amount should be appropriately lowered. In another case, if the grinding ability is appropriate and the airflow conveying capacity is insufficient, the same amount may cause a large amount of spit, wherein the fine powder content is large, and at this time, the air volume should be increased and the conveying capacity should be enhanced. Therefore, in the operation process of the slag vertical mill, the material balance principle is used to pre-discover the problems in the vertical mill operation, so that corresponding measures are taken to prevent unnecessary shutdown and debugging failure.

Third, the appropriate wind temperature and air volume

The slag vertical mill generally adopts negative pressure operation, and a large amount of hot air is required for material transportation, grading and drying. The air volume should first meet the requirements of conveying materials. If the air volume is too small, a large amount of qualified fine powder can not be transported out in time; excessive air volume not only causes energy waste, but also causes the product to run rough. The temperature of the wind should be determined according to the moisture content of the material being ground. If the water is too large, the air temperature should be increased. If the water is small, the air temperature should be lowered, but the inlet air temperature should be less than 350 °C. (Excessive air temperature will cause damage to the vertical mill.) In addition, in order to prevent dew condensation (condensation) of the mill bag filter, the wind temperature should be controlled within the range of 80-100 °C.