How to process highly magnetic iron ore?

At present, there are about 300 kinds of iron-containing minerals found in nature. According to their chemical composition, iron ore can be divided into magnetite, hematite, limonite and siderite; and iron ore is often classified according to its chemical composition. Depending on the specific magnetization coefficient of the substance, iron ore is divided into strongly magnetic and weakly magnetic minerals.

01 Single magnetite

Most of the iron minerals in a single magnet ore are magnetite. Because magnetite ore has a simple composition, strong magnetism, and is easy to grind and separate, weak magnetic separation methods are often used.

When the grinding particle size is greater than 0.2mm, most iron ore magnetic separation plants usually use one stage of grinding-magnetic separation;

When the grinding particle size is less than 0.2mm, two stages of grinding-magnetic separation are used;

If qualified tailings are separated in the coarse grinding stage, the iron ore magnetic separation plant should adopt the staged grinding-magnetic separation process;

For dry and water-scarce areas, iron ore concentrators may consider adopting dry grinding-dry magnetic separation process.

02  Polymetallic magnetite

Gangue minerals containing polymetallic magnetite often contain silicate and carbonate minerals, cobalt pyrite, chalcopyrite or apatite, etc. It is recommended to use a weak magnetic separation-flotation combined process, that is, using weak magnetic separation The process first recovers iron, and then uses the flotation process to recover sulfide or apatite, which is conducive to obtaining higher mineral processing indicators.

Usually, the combined process of weak magnetic separation and flotation is also divided into two types: weak magnetic separation-flotation, and flotation-weak magnetic separation. The difference between these two processes is that the conjoined destinations of magnetite and sulfide are different.

When using the weak magnetic separation-flotation process, conjoined organisms mainly enter the iron concentrate.

When using the flotation-weak magnetic separation process, the conjoined bodies enter the sulfide concentrate.

This shows that under the same grinding particle size, the combined process of first flotation and then magnetic separation can obtain iron concentrate with low sulfide content and sulfide concentrate with high recovery rate.