From mined ore mines, general grade is low. A lot of iron ore iron only 20-30%, for example, only 0.5 1% copper ore containing copper. Such a low grade ore smelting directly, not only technically there are difficulties, also on the economic not worthwhile. So, lean ore of low grade, need to use before smelting ore dressing method, through the mineral processing equipment, separate gangue and useful minerals in the ore, make the grade, the requirements of raw material for smelting. In addition, the ore often contains several useful compounds (such as copper, lead, zinc, or copper, zinc, copper, iron, etc.), must as far as possible to their recycling respectively, to achieve a goal only dressing is very good.

In addition to the composition in the ore, often contain harmful impurities. Harmful impurities into the metal will affect metal smelting, and sometimes will complicate the process of smelting even harder. Such as copper and lead ore genesis, harmful impurities zinc; Zinc ore genesis of harmful impurities of iron; Harmful impurity in the iron ore sulfur and phosphorus. These harmful impurities must be before smelting in ore dressing method, may go out or reduced according to the product quality standard.

So, with the development of metallurgical industry, mineral processing status and role is very important, become the important link of the metallurgical industry must be less.