There are significant opportunities for the mining and processing of banded magnetite deposits on the African continent. A natural iron-ore deposit is a single deposit with little waste rock mixed into it. With massive iron-ore deposits, the head grade can be 60% to 70%, which means fewer impurities need to be removed before processing the ore into pig iron. The most massive ore bodies consist of hematite, which are the principal and the most stable of the iron oxides. The first step in the comminuting process and liberating a mineral from the ore body begins at the mining stage, with drilling or blasting and excavation used to generate materials that are easily transportable.
Crushers are then used to produce coarse size reduction and grinding mills are used to produce finer particles. As for the crushing process, Sanme crusher is a great option!
The ore mined from massive ore bodies is suitable for use in blast furnaces, they simply need to be crushed into pieces of between 10 mm and 25 mm, and then transported as lumpy ore to iron and steel plants worldwide. The ore is first crushed to size and then passed through a dense media separation process. The dense medium, with a specific gravity of around 3.6 t/m3, is created by mixing water with finely ground ferrosilicon powder. Anything with a specific gravity of less than 3.6 t/m3, for example silica-based rock, which has a density of 2.8 t/m3, will float, while the lumps of hematite iron-ore with a density of around 5.0 t/m3 will sink. What you see coming out of this process are big rocks floating in what looks like black water.
There are several kinds of comminution. In-pit comminution includes blasting, rock breaking and continuous mining; scrubbing, which is used as a polishing agent and not primarily for size reduction; crushing, which includes gyrators, jaw crushers, impactors and mineral screening; and grinding mills, which include the most commonly used semiautogenous grinding (SAG) mills, autogenously grinding (AG) mills, ball mills and rod mills..