What are the reasons for the decline in the output of ball mills? These 8 factors cannot be ignored!

What are the reasons for the decline in the output of ball mills? These 8 factors cannot be ignored!

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

01)The design of the ball mill is unreasonable

The ball mill can be divided into single compartment and double compartment. The length ratio of each compartment is different. In the case of a single compartment, the length ratio of 1 compartment should be 30%~40%, and the length ratio of 2 compartments should be 60%~ 70%; in the case of double compartments, the length ratio of the 1st and 2nd warehouses is 25%~30%, and the length ratio of the 3rd warehouse is 45%~50%. refer to.)

If the length ratio design is unreasonable, it is very likely to cause the unbalanced ratio of coarse and fine grinding of the ball mill, resulting in the phenomenon of over-coarse or over-fine products, thus affecting the output of the ball mill.

Solution: Choose ball mill equipment produced by regular manufacturers, preferably ball mill manufacturers with design and R&D teams. Do not buy equipment produced by small manufacturers or small workshops without production qualifications, so as not to affect the output.

02)Ball mill ventilation is not good

In the 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, resulting in the generation of water vapor from the water-containing material. On the liner and steel balls of the ball mill, the phenomenon of paste ball or paste grinding is caused.

Solution: Control the ventilation volume of the ball mill, and the effect of passing through the ball mill is good, which can not only bring out qualified fine materials in time, but also effectively reduce the phenomenon of over-grinding and reduce the temperature of the ball mill.

03)The feeding of the ball mill is unreasonable

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 waste of media; if the ball mill is fed too much, the grinding capacity of the ball mill will be insufficient. , leading to saturation.

Solution: It is necessary to strictly follow the feeding standard for feeding.

04)The ball mill enters the grinding particle size is too large

The grinding particle size of the ball mill is too large, and it is difficult to adapt to the impact and effect of the grinding body, and the first chamber of the ball mill will be broken to increase the amount of steel balls to enhance the impact and grinding capacity. condition.

Solution: Under normal circumstances, the grinding particle size of the ball mill is generally controlled below 20mm. For large ball mills, due to the strong crushing ability, the grinding particle size can be adjusted to 25~30mm.

05)The water in the ball mill is too large

When the water content of the ball mill into the grinding material is large, the grinding body and the lining plate will adhere, causing paste grinding, clogging the grate plate, and causing the phenomenon of full grinding. However, containing a small amount of water can effectively reduce the temperature of the ball mill, reduce static electricity, etc. Therefore, the average water content of the ball mill into the grinding is generally controlled at <15%.

Solution: Reasonably control the water entering the mill, and adjust the water ratio according to the properties of different materials.

06)The gradation of steel balls in the ball mill is unreasonable

The grading of steel balls in a ball mill is to achieve impact and grinding of materials with different particle sizes to improve the grinding efficiency. Therefore, the gradation of steel balls in a ball mill is very important. The general gradation range is between 25% and 35%. In the majority of 28% to 32%.

Solution: Scientific and reasonable calculation of steel ball gradation, the specific calculation method can be found in the article: How to correctly add steel balls when the ball mill is first activated.

07)The temperature of the material entering the ball mill is too high

Generally, when the temperature of the material entering the ball mill is too high, the grinding efficiency is easy to reduce. When the temperature of the ball mill exceeds 100 °C, the air film isolated from each other on the surface of the small particles of the material will be destroyed, resulting in adhesion.

Solution: In order to reduce the temperature in the mill and improve the grinding efficiency, a small amount of mist water can be sprayed into the grinding bin to reduce the temperature in the mill to below 50°C.

08)The dosage of grinding aid is unreasonable

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

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