The magnetic separator made of permanent magnets is called permanent magnetic separator. Magnetic separation is based on the magnetic difference of mineral particles. When the mineral particles and gangue particles pass through the magnetic field of the magnetic separator, due to the different magnetic properties of the mineral particles, they move in different ways under the action of the magnetic field. Magnetic ore particles are attracted by the magnetic force and adhere to the cylinder of the magnetic separator. After being brought to a certain height with the cylinder, they leave the magnetic field.
The magnetic field is divided into uniform magnetic field and non-uniform magnetic field. In a uniform magnetic field, the magnitude and direction of the magnetic field at any point are the same, and the magnetic force acting on the magnetic ore particles is uniform. At this time, the ore particles are in a balanced state, so the purpose of separation cannot be achieved. In a non-uniform magnetic field, the magnitude and direction of the magnetic field strength are different. At this time, the magnetic force acting on the magnetic ore particles is not uniform, so the magnetic ore particles move under the action of the magnetic force to achieve the purpose of separation.
The magnetic separator only uses a non-uniform magnetic field. In a non-uniform magnetic field, the magnetic force acting on the magnetic mineral particles is proportional to the degree of non-uniformity. The more uneven the magnetic field, the greater the magnetic force acting on the magnetic mineral particles. The inhomogeneity of the magnetic field strength is usually expressed by the magnetic field gradient, and the unit is Oersted/cm.
The magnetic separator is one of the most widely used and most versatile models in the industry, and is suitable for reusing powdered granules to remove iron powder. Magnetic separators are widely used for resource recovery in wood industry, mining, ceramics, chemical, food and other factories. The magnetic separator is suitable for wet or dry magnetic separation of manganese ore, magnetite, pyrrhotite, roasted ore, ilmenite and other materials with a particle size of less than 3mm. It is also used for the deironing of coal, non-metallic minerals, building materials and other materials.
The magnetic system of the magnetic separator is mostly made of high-quality ferrite material or composited with rare earth magnet steel. The average magnetic induction intensity of the cylinder surface was 800-4000mT before. Due to the development of technology, the magnetic separator can be made into a roll shape, and the magnetic field strength has also been increased to 8000mT, which is the highest magnetic field strength ever measured.