1. Conventional discharge particle size range

Basic range: In most cases, the beneficiation ball mill can grind the material to 0.074–0.45 mm (40–200 mesh).

Fine grinding limit: Some equipment can reach micron level (1–10 microns) or submicron level (<200 nanometers) by optimizing design (such as wet overflow type) and adjusting parameters.

2. Typical grinding fineness of different ores

Ore type Particle size requirement (mesh) Corresponding millimeter range Application scenario

Gold ore 200–400 mesh 0.074–0.038 mm Improve gold recovery rate ‌

Copper ore 200–325 mesh 0.074–0.045 mm Flotation process requirements ‌

Iron ore 100–200 mesh 0.15–0.074 mm Conventional beneficiation process ‌

Lead-zinc/nickel ore 200–325 mesh 0.074–0.045 mm Meet flotation or leaching requirements ‌

3. Key factors affecting particle size ‌Equipment type ‌

Grate ball mill ‌: Suitable for medium-coarse grinding, the output particle size is relatively coarse ‌. ‌

Overflow ball mill ‌: Better fine grinding effect, suitable for micron-level grinding ‌. ‌

Adjustment of operating parameters

Speed: Increasing the speed can enhance grinding efficiency, but energy consumption and wear need to be balanced.

Grinding media: Small-sized steel balls or ceramic balls are easier to obtain fine particles.

Feed speed: Reducing the feed speed can extend the grinding time and improve the fineness.

Ore characteristics

Ores with high hardness (such as anthracite) require longer grinding time and higher energy consumption.

The smaller the feed particle size, the finer the final output, and the processing efficiency is improved.

4. Precautions

Process matching: It is not the finer the better, and it needs to be combined with the economic requirements of subsequent mineral processing processes (such as flotation and leaching).

Energy consumption and cost: Ultrafine grinding may significantly increase equipment wear and energy consumption, and the benefits need to be comprehensively evaluated.