The beneficiation stage is mainly divided into three stages: pre-separation, separation and post-separation. Grinding is in the pre-separation stage. Therefore, the output of the ball mill has a certain influence on the separation effect, and even the recovery rate and concentrate grade. Therefore, how to ensure the output of the ball mill has become a topic of concern, so what are the reasons that affect the output of the ball mill? Unreasonable ball mill design.

The ball mill can be divided into single compartment and double compartment. The length ratio of each compartment is different. In the case of single compartment, the length ratio of compartment 1 should be 30%-40%, and the length ratio of compartment 2 should be 60%~ 70%; In the case of double compartments, the length ratio of compartment 1 and compartment 2 is 25%~30%, and the length ratio of compartment 3 is 45%~50% (the design ratio of products of various manufacturers may be different, the above data is for reference only.)

If the design of the length ratio is unreasonable, it is very likely that the ratio of coarse and fine grinding of the ball mill will be unbalanced, resulting in the phenomenon of over-thickness or over-fineness of the product, which will affect the output of the ball mill.

Poor ventilation of ball mill

Under normal operation of the ball mill, due to the repeated impact and friction of the medium in the cylinder, the temperature in the mill continues to rise, causing water vapor to be generated by the water-bearing materials. If the ball mill is not well ventilated, the water vapor cannot be discharged in time and adhere to the ball mill liner and steel balls cause paste ball or paste grinding phenomenon.

Unreasonable feeding of ball mill

During the operation of the ball mill, uniform feeding is a necessary condition to ensure the normal operation of the ball mill. If the feeding is too small, the impact of the steel balls of the ball mill will increase, resulting in media waste. If the ball mill feeds too much, the grinding capacity of the ball mill will be insufficient, which will results in saturation.

Large feeding particle size of the ball mill

The feeding particle size of the ball mill is too large, and the impact and action of the grinding body are difficult to adapt. The first chamber of the ball mill need to increase the amount of steel balls to enhance the impact and grinding ability. This situation is likely to cause unreasonable crushing in one chamber.

Grinding high moisture materials

When the water content of the grinding material is large, the grinding body and the liner will stick, causing paste grinding, blocking the grate plate, and causing the full grinding. However, a small amount of water can effectively reduce the temperature of the ball mill and reduce static electricity. Therefore, the average water content of the ball mill is generally controlled at <15%.

Unreasonable grading of steel balls in ball mill

Ball mill steel ball grading is for the impact and grinding of materials with different particle sizes to improve the grinding efficiency. Therefore, the grading of ball mill steel balls is very important. The general grading range is between 25% and 35%, but in actual applications, the gradation is 28%~32% is mostly. The temperature of the material entering the ball mill is too high

Generally, when the temperature of the input material is too high, it is easy to reduce the grinding efficiency. When the temperature in the ball mill exceeds 100℃, the air film isolated between the surface of the small particles of the material will be destroyed, causing adhesion.

Unreasonable dosage of grinding aid

Under the premise of not harming the performance of the product, the ball mill can add a small amount of grinding aid, which can not only accelerate the crack propagation in the material crushing, reduce the mutual adhesion between fine powders, effectively improve the grinding efficiency, but also improve the ball mill efficiency under energy saving.

However, the grinding aids for ball mills need to be added in accordance with national standards. In general cement production process in China, the addition of grinding aids should not exceed 1%. The proportion of grinding aids for other materials can be inquired through national standards.