Usually, a ball mill
has a range of output, and the output is normal in this range. If the output of the bead mill suddenly drops, 80% is due to "saturation." "Saturation" is a common abnormal phenomenon in the operation of ore ball mill
. The direct reason is that the amount of feed and discharge is out of balance. In a short time, the amount of material in the memory is too much.
I. Causes of "saturation"
1. Too much feed, grinding capacity of the grinding body cannot adapt.
2. The size of the material entering the mill becomes larger and the hardness becomes larger. The feed is not reduced in time, and a large amount of uncrushed materials are caught in the caulking of the silo panel, resulting in clogging, so that the material cannot be discharged in time.
3. The water content of the material entering into the mill is too large (2.0% or more), and the ventilation is poor, and the water vapor and fine materials generated during the grinding process cannot be brought out of the ball mill in time, resulting in the material adhering to the lining of the steel ball due to high humidity. The surface of the plate reduces the grinding efficiency, and at the same time, due to the increase of the wet material, the flow rate is slowed down and the discharge is difficult. The "saturation" phenomenon caused by this reason is more common.
4. The ball grading is unreasonable, too many balls, the average diameter is too small, or the filling rate is too low, resulting in reduced grinding.
5. The partition board or quilting is blocked by debris, and the boring hole becomes smaller, causing "saturation."
6. In the closed-circuit system, the powder separator's powder separation efficiency is greatly reduced, too much material is returned, and the amount of feed material is not reduced. The grinding capacity of the mill cannot be adapted to cause blockage.
7. Partial or breakage of one or two of the bulkhead plates results in grinding of the grinding body and the grinding ability is greatly reduced.
Second, "saturation" processing method
The following treatment methods can be used for the reason that the ball mill “saturation”:
1. Reduce the amount of feeding, if the effect is not obvious, you need to immediately stop feeding, so that the ball mill is running under less or no material, in order to produce more heat, so that moisture evaporates, thereby reducing the ball and the compartment board Clogging phenomenon.
2. In the case of stopping the feeding, add grinding materials to the grinding mill (the raw material grinding plus dry coal or quicklime, cement grinding and dry slag or dry slag), after grinding close to normal, feed a small amount of material, Then gradually increase the amount of feed until normal feeding.
3. Increase the ventilation of the ball mill, so that the fine material discharged as soon as possible, observe whether the increase of the main motor current, if the current increases, indicating that the phenomenon of full grinding has been eliminated, then you can gradually increase the amount of feed.
4. If the above method is not valid, stop the machine and open the mill door to check the partition board and sampan board to see if it is blocked.
Matters needing attention: When the ball mill is fully ground, stop grinding can only be used as the last means, because when the grinding is completed, the load of the ball mill becomes large. Once it is stopped in full grinding, it may cause the ball mill to fail to start.
5. When the sizing is very serious, sometimes need to use the method of shutting down the grinding, the specific method is as follows: pour out the ball and material in the hopper, thoroughly sculpt the lining board and the crust on the steel ball, clear the quilt of the septum board Clogs, then reconfigure the ball or load the poured ball.