The magnetic system of magnetic separation equipment can be divided into open and closed magnetic systems according to the arrangement of magnetic poles. The so-called open magnetic system refers to a magnetic system in which magnetic poles are arranged adjacent to each other on the same side and magnetic ferrites are not induced between magnetic poles. In this kind of magnetic system, the magnetic flux travels through the air gap between the magnetic poles, and the magnetic resistance of the magnetic circuit is large. Therefore, the magnetic field strength and the magnetic field gradient of such a magnetic system are not too high, ie, the magnetic field force is not too high, and it is suitable for weak magnetic field magnetic separation equipment for selecting strong magnetic ores or materials. This kind of magnetic system has a larger selection space, so the magnetic processing equipment using this kind of magnetic system has a higher processing capacity.
The open magnetic system can be divided into three types according to the magnetic pole arrangement characteristics:
1 Plane magnetic system: The magnetic poles are arranged in a plane. For example, tape magnetic separators use such magnetic systems.
2 Surface magnetic system: The magnetic poles are arranged in a cylindrical surface. For example, a magnetic field weakening magnetic separator is used for such a magnetic system.
3 tower magnetic system: magnetic poles arranged in a tower. Some permanent magnetic sludge removal tanks use this type of magnetic system. The magnetic susceptibility of weak magnetic minerals is much smaller than that of ferromagnetic minerals, so the magnetic force required to recover weak magnetic minerals is much larger than that of ferromagnetic minerals. The magnetic field strength and magnetic field gradient of the open magnetic system are small, so the magnetic field force is small, and the requirement for recovering weak magnetic minerals cannot be satisfied. To make the selected magnetic space of the open magnetic system produce a strong magnetic field force, only high magnetic potential, which requires the consumption of a large number of metal wires and magnetic materials with high magnetic energy. This is very uneconomical and unreasonable. In order to solve the above problems, a closed type magnetic system has appeared. The closed type magnetic system refers to a magnetic system in which magnetic poles are arranged opposite to each other, and a special-shaped ferromagnetic medium (such as a round tooth with a toothed surface, toothed Plates, balls, filaments, nets, etc.). If there are ferromagnetic media (such as toothed disks and balls) between open magnetic poles, such magnetic systems may also be referred to as closed magnetic systems. These ferromagnetic media are magnetized in the magnetic field of the magnetic pole and become induction magnetic poles. The air gap between the magnetic poles in this type of magnetic system is small, the path of the magnetic flux through the air gap is short, the magnetic resistance of the magnetic circuit is small, and the magnetic flux leakage is small, so the magnetic field strength of the selected subspace is large, and because the ferromagnetic medium has special The shape, and thus the magnetic field gradient, is suitable for strong field magnetic separation equipment for the selection of weak magnetic ores.