In a mineral processing plant, grinding is a continuation of the ore crushing process and the final step before ore separation. The task of grinding operations is to completely or substantially separate the useful components in the ore into individual particles, while avoiding over-grinding as much as possible, providing the beneficiation process with a feed slurry of suitable particle size and concentration, creating conditions for better recovery of useful components from the ore. The quality of beneficiation indicators largely depends on the quality of the grinding product. Therefore, the grinding product should meet the particle size requirements of different beneficiation methods to ensure the acquisition of high-quality concentrate and full recovery of useful minerals. If the grinding fineness is insufficient, the various mineral particles will not achieve sufficient individual separation, and the beneficiation indicators will not be high; however, excessive grinding will produce slime, which cannot be effectively recovered by any beneficiation method. For example, it is difficult to recover fine particles smaller than 20.0 μm in gravity separation, and the effective recovery limit for flotation is 5.0–10.0 μm. Over-grinding produces slime, which increases reagent consumption, reduces selectivity in the flotation process, and may even render flotation impossible, creating difficulties for subsequent operations.
Furthermore, the grinding product must meet the concentration requirements of the beneficiation operations. Each beneficiation operation has an appropriate concentration range; too high or too low a concentration is unsuitable. It should be noted that the optimal fineness and concentration of the grinding product are determined through mineral processing tests.