The grinding process refers to the path (technical process) through which the slurry flows during the grinding operation. Grinding can be divided into open-circuit grinding and closed-circuit grinding. Open-grinding is the material discharged from the grinding machine and sent directly to the next operation: while the closed-mill grinding material is discharged into the classifier, the fine particles will be Qualified products are dispensed in time and sent to the next operation, while the coarse grade is returned to the mill for re-grinding. This not only improves the processing capacity of the mill, but also avoids over-grinding and reduces muddy phenomenon. Therefore, the closed-circuit process of the combination of the mill and the grading operation is widely used in the selection plant.

Practice has proved that: using one or two stages of grinding process, the ore can be economically ground to the required size of the sorting, without having to use more grinding sections, more than two stages are usually determined by the requirements of the stage selection. .