Separator technology continues to progress in the development of today's society

Magnetic materials handling technology is one of the foundations, the past 30 years, magnetic separation has made great progress. The advantage of magnetic material is its wide range of applications. Magnetic separation process innovation power and can achieve great success also lies in the process can be used in different industrial sectors. This paper will present situation and future development of magnetic direction of development is reviewed.
Generating the magnetic field and the magnetic field gradient
Although the permanent magnet used for decades to generate a magnetic field in the magnetic separator, however, until cheap to produce high energy product and high coercive force of the ferrite magnet appeared before they get further permanent magnet application. Recently, the development of a strong rare earth permanent magnet materials, a new generation of permanent magnet roller drum magnetic separator appears. In such a roll is generated on the surface of the magnetic induction up to 1.9T and a high magnetic field gradient strength. Early, with the electromagnet core generates a magnetic field in the magnetic separator. Although this magnet still plays an important role, but, as the permanent magnets and the resistor of the air core coils and superconducting rotating air core coils spin occurs it has lower importance. The main disadvantage of the magnet core, which can be achieved by a magnetic field strength of the magnetic induction saturation magnetization of iron restriction. And, this magnet is restricted enlarged scale. Even moderate working gap, the magnet makes the amplification reduces the magnetic induction field, increase the weight of the separator. This magnet produces a magnetic flux density of not more than 1T.
On the contrary, there is resistance in the larger spiral magnet workspace produce up to 2T magnetic induction. This allows the manufacture of large magnet strong magnetic separator, its processing capacity can reach 100t / h. Superconducting magnet magnetic induction intensity can increase to 5T or higher, though, the most frequently applied magnetic separator magnetic induction is generally not more than 2T. pot magnets
There are two ways to generate the magnetic field gradient method, as seen from formula (1) is seen, the magnetic field gradient is also very important. By proper arrangement of permanent magnet blocks, or the magnet properly sharpened, or is reasonably arranged magnet poles, the magnetic induction intensity of the magnetic field may change and generating a magnetic field from the magnets as a function of the distance. This is called open gradient magnetic field gradient, in most drum magnetic separator, magnetic separator roller and plate separator machine is the application of the magnetic field gradient. In the hanging magnet magnetic field gradient is generally to 1T / m, in the rare earth permanent magnet roller separator machine, magnetic field gradients up to 100T / m.
The ferromagnetic objects (balls, mesh or steel wool) into the magnetic separator magnetic field can greatly improve the magnetic field gradient. The magnetization object (often referred to as media) can be produced when the magnetization of up to 5 * 104T / m local magnetic induction gradient. This innovation can greatly increase the range of magnetic force, so, can handle a lot of weak magnetic separator and even anti-magnetic fine particles. magnetic separation