How to improve the processing capacity of mining machines

Methods to improve the processing capacity of ball mills in mines

1. Change the wearability of raw ore

In the grinding process, certain chemicals can be added to improve the grinding effect and increase the grinding efficiency.For example, choosing a suitable agent according to the actual situation can reduce the hardness of the ore and make the ore easier to grind.According to relevant studies, the reasonable addition of chemicals can reduce the wear of the mill liner and steel ball and reduce energy consumption.Another method is to heat the minerals in the ore to change the mechanical properties of the entire ore, thereby reducing the hardness.This method can effectively improve the processing capacity of the ball mill when economic and site conditions permit.

2. More crushing and less grinding

Reducing the particle size of the incoming grinding is an important way to improve the processing capacity of the ball mill.The efficiency of crushing ore is significantly higher than that of grinding ore, and the energy consumption of crushing ore is low, which is about 12% to 25% of the energy consumption of grinding ore.To achieve the specified grinding fineness, if the grinding particle size is large, the workload of the mill will increase, and the energy consumption and power consumption will also increase.Therefore, it is required that the particle size of the crushed ore product should be small, so as to “crush more and grind less”.For example, by optimizing the crushing process, such as strengthening blasting operations and adopting efficient crushing equipment, the particle size of the crusher can be reduced, so that the particle size of the material entering the ball mill is smaller, thereby improving the processing capacity of the ball mill.

3. Reasonable filling rate

The filling rate has an important influence on the processing capacity of the ball mill.Under the condition of a certain speed of the ball mill, the filling rate is large, the steel ball strikes the material many times, the grinding area is large, and the grinding effect is strong, but the power consumption is also large.The filling rate is too high and it is easy to change the movement state of the steel ball, reducing the impact effect on large particulate materials.Conversely, the filling rate is too small and the grinding effect is weak.At present, many mines set the filling rate at 45% to 50%, but strictly speaking, it is not necessarily reasonable, because the actual conditions of each selected plant are different, copying other people's data for ball loading can not achieve the ideal grinding effect, it depends on the situation.For example, a copper and gold mine in Indonesia increased the filling rate of steel balls from 14% to 18%, and the processing capacity of the mill increased by 5% to 10%.

4. Reasonable steel ball size and ratio

Accurate steel ball size and its matching ratio are very important for grinding efficiency and ball mill processing capacity.The ball diameter is too large and the crushing force is also large, causing the ore to be broken in the direction of penetration, which is not in line with the purpose of grinding, and when the filling rate of the steel ball is the same, the ball diameter is too large, resulting in too few steel balls, the probability of crushing is low, the phenomenon of over-crushing is aggravated, and the particle size of the product is uneven.The steel ball is too small, the crushing force on the ore is small, and the grinding efficiency is low.

5. Precise replenishment of the ball

In production, the grinding effect of steel balls and ore will cause the wear of steel balls, resulting in changes in the ratio of steel balls of various sizes, affecting the grinding process and causing changes in the fineness of the polished mineral products.Therefore, a reasonable steel ball replenishment system is needed to stabilize production and maintain a reasonable steel ball ratio to ensure the processing capacity of the ball mill.For example, by changing the steel ball replenishment scheme of Yunnan Phosphating Group Anning Mining, under the premise of ensuring the monomer dissociation of the milled mineral products, the amount of over-grinding of the milled mineral products is effectively reduced, and the grinding efficiency and production capacity are greatly improved.

6. Appropriate grinding concentration

The size of the grinding concentration affects the specific gravity of the slurry, the degree of adhesion of the ore particles around the steel ball, and the fluidity of the slurry.The grinding concentration is low, the slurry flows quickly, and the degree of adhesion of the material around the steel ball is low, so that the impact and grinding effect of the steel ball on the material is weak, the particle size of the ore discharge is unqualified, and the grinding efficiency is not fully utilized; the grinding concentration is high, the degree of adhesion of the material around the steel ball is good, and the impact and grinding effect of the steel ball on the material are good, but the slow flow of the slurry can easily cause the material to be crushed, which is not conducive to increasing the processing capacity of the mill.In production practice, the grinding concentration is often controlled by controlling the ore feed volume, water supply volume, or adjusting the grading effect of the mill.

7. Optimize the grinding process

In actual production, the grinding process can be optimized for the ore properties of the raw ore, such as the inlay particle size of useful minerals, the dissociation degree of monomers, and the inlay particle size of gangue minerals.Such as pre-tail polishing, pre-enrichment, stage grinding, pre-grading and other operations to optimize the grinding system, on the one hand to reduce the amount of grinding, on the other hand to recover useful minerals early.This can improve the processing capacity of the ball mill and improve the mineral processing efficiency at the same time.

8. Improve grading efficiency

The influence of grading efficiency on grinding efficiency and ball mill processing capacity is self-evident.High grading efficiency means that qualified particle grades can be discharged in a timely and efficient manner, while low grading efficiency means that most of the qualified particle grade products are not discharged and returned to the mill for re-grinding, which can easily cause over-grinding, which affects the later sorting effect.The use of two-stage grading or improved grading equipment and other methods can improve the grading efficiency.

9. Automatic control of grinding system

There are many variable parameters in grinding operations, and one change will inevitably cause many factors to change one after another.The automatic control of grinding operations can keep the grinding grading in a stable and suitable state, and improve the grinding efficiency and the processing capacity of the ball mill.According to foreign reports, the automatic control of the grinding grading circuit can increase the production capacity by 2.5% to 10%, and the processing of one ton of ore can save 0.4~1.4kWh/t of power consumption.

In short, the processing capacity of a mine ball mill cannot be generalized. It is necessary to figure out the type of ball mill and the nature of the materials processed.In actual production, some necessary measures should also be taken in accordance with the situation to improve the processing capacity of the ball mill, so that the grinding effect can be doubled with half the effort and economic benefits can be improved.