How to choose magnetic separator?

Magnetic separation refers to the use of magnetic equipment to separate magnetic materials from other materials based on their magnetic properties. The equipment machinery used for this operation is called magnetic separator, and magnetic separator is generally called magnetic separation equipment. Let's first understand the classification of magnetic separators, so that we can choose the appropriate magnetic separators.

1. Classify according to the strength of the magnetic field.

It can be divided into weak magnetic field magnetic separator, medium magnetic field magnetic separator, strong magnetic field magnetic separator and high gradient magnetic separator.

Weak magnetic field magnetic separator is mainly used for magnetic separation of strong magnetic materials, the specific magnetic susceptibility coefficient is greater than 38×10-6m/kg, such as magnetite, maghemite, titanium magnetite, pyrrhotite, zinc iron tip Ferrimagnetic minerals such as spar. Weak magnetic field magnetic separator is mainly divided into dry weak magnetic field magnetic separator and wet weak magnetic field magnetic separator. Dry weak magnetic field magnetic separator can also be divided into magnetic roller and permanent magnetic roller magnetic separator.

The magnetic field magnetic separator is mainly used for the selection of medium and strong magnetic minerals such as ilmenite and pseudohematite and the removal of iron from non-metallic minerals. The magnetization coefficient is divided into 1.9×10-6m/kg-38×10-6m/kg.

The strong magnetic field magnetic separator mainly adopts a closed magnetic system and a certain shape of the induction pole or magnetic medium, which generates a strong magnetic field force in its partition, which can effectively separate weak magnetic minerals. According to the working form, it can be divided into dry type and wet type. The magnetic susceptibility coefficient of the weak magnetic mineral materials separated by the strong magnetic field magnetic separator is less than 1.9×10-6m/kg.

The high gradient magnetic separator improves the magnetic field force and the processing capacity of the magnetic separator through the interaction between the magnetic medium and the particles, and is mainly used to solve the separation problem of particulate minerals. High gradient magnetic separators are mainly divided into SLON, YKC, SSS-II, GCG, DCH, ZGCX and other series.

2. Classify according to the selected medium.

The magnetic separator is based on the selection of magnetic separator and wet magnetic separator.

Dry magnetic separators and wet magnetic separators have different requirements on the moisture content of materials. The dry magnetic separator requires the feed material to have low moisture content, and the standard is that the surface of the material is dry, has good fluidity, and does not form adhesion and unity. The wet magnetic separator has requirements on the concentration of the ore pulp. There is no obvious limit to the concentration during coarse magnetic separation, but the material concentration should not be too low to effectively control the negative force of the fluid during the beneficiation process, while the concentration of fine particles and fine particle materials is required to be slightly higher. , to ensure the recovery of magnetic minerals.

3. Classify according to the type of magnetic field.

Magnetic separators can be divided into constant magnetic field magnetic separators, rotating magnetic field magnetic separators, alternating magnetic field magnetic separators, and pulsating magnetic field magnetic separators.

The constant magnetic field magnetic separator uses permanent magnetic materials, electromagnets, and screw tubes as magnetic sources. The magnitude and direction of the magnetic field strength vary with time.

The magnetic field magnetic separator uses a magnet as a magnetic source, and the magnetic pole rotates around the axis, and the magnitude and direction of the magnetic field strength change with time.

The alternating magnetic field magnetic separator uses an alternating current electromagnet as a magnetic source, and the magnitude and direction of the magnetic field strength change with time.

The pulsating magnetic field magnetic separator uses an electromagnet that passes both direct current and alternating current as the magnetic source, and the magnetic field strength changes with time, but the direction remains unchanged.

4. According to the magnetic source classification.

It can be divided into permanent magnet magnetic separator and electromagnetic magnetic separator.

The permanent magnet selector uses ferrite, NdFeB and other permanent magnet materials to generate a working magnetic field, while the electromagnetic selector uses electromagnets, screw tubes and magnetizers to generate a magnetic field.

5. According to the classification of magnetic system.

According to the main structure of the magnetic separator, it can be divided into drum magnetic separator, roller magnetic separator, disk magnetic separator, ring magnetic separator, belt magnetic separator and so on.

The cylinder type magnetic separator is designed with a magnetic separation function structure, and most of them are weak magnetic field and medium magnetic field magnetic separators. There is a cylinder outside to protect the internal magnetic system, so it is called cylindrical type;

The magnetic separation working surface of the roller magnetic separator is completed on the round roller of the belt structure, mainly including the induction roller magnetic separator and the permanent magnetic roller magnetic separator with its own magnetic field;

The magnetic material of the disk magnetic separator is finished in the sorting disc;

The magnetic separation medium of the ring magnetic separator is installed in the ring structure, and the ring magnetic separator is developed on the basis of the disk magnetic separator, and its working principle is similar;

The belt-type magnetic separator sends the ore belt into the uneven magnetic field, and the magnetic induction pole absorbs the magnetic particles from the belt, and continuously moves to the second magnetic system to form a continuous discharge of magnetic minerals.

6. Classified according to the number of magnetic coefficients.

Magnetic separators can be divided into single-barrel magnetic separators, double-barrel magnetic separators and combined multi-barrel magnetic separators.

7. Classify according to the movement form of magnetic particles in the magnetic field.

Classified according to the movement form of magnetic particles in the magnetic field, it can be divided into magnetic tumbler and non-magnetic tumbler.

The magnetic separator is designed for magnets where strong magnetic minerals are magnetized into magnetic poles in a magnetic field. This type of magnetic separator can effectively improve the taste of the concentrate, but may cause a small decrease in some recoveries.

Magnetic separator can be used for magnetic separation to remove strong magnetic minerals. Although the strong magnetic minerals are magnetized during the magnetic separation process, the outer cylinder of the system and the magnetic system are fixed on the same bearing, so magnetic reversal does not occur.

8. According to the magnetic structure classification.

According to the classification of magnetic structure, it can be divided into open magnetic separator and closed magnetic separator.

The open magnetic circuit magnetic separator refers to the magnetic system in which the magnetic poles are adjacent on the same side, and there is no inductive magnetic medium between the magnetic poles and the opposite sides of the magnetic poles. Since the magnetic flux starts from the N level, the magnetic flux is scattered, the air gap reluctance is large, the magnetic field strength is low, and the magnetic field gradient is small.

Closed magnetic separator means that the surface of the magnetic pole is opposite to the surface, and the induction magnetic medium of various shapes is often placed between the magnetic poles to become a part of the ferromagnetic circuit. This kind of magnetic system chooses gap or single layer or multi-layer, but the gap is small, the magnetic flux is generally a straight line, the resistance is small, the magnetic flux is concentrated, the magnetic flux density is large, the magnetic field strength is high, and the surface curvature of the induction pole is large, forming a higher magnetic field gradient. Because the magnetic force generated by the magnetic mine is equal to the product of the magnetic field intensity and the magnetic field gradient, the magnetic separation function of the strong magnetic field produces a large magnetic force.

9. Classify according to the way of magnetic mineral selection.

It can be divided into suction magnetic separator, suction magnetic separator and suction magnetic separator.

The concentrate quality of the suction magnetic separator is generally better, and the recovery rate of the suction magnetic separator is generally higher. The suction magnetic separator mainly relies on the gravity of the mineral itself to discharge it into magnetic products.

10. According to the ore feeding method, classify the tank structure type.

Magnetic separators are classified into downstream magnetic separators, countercurrent magnetic separators and semi-countercurrent magnetic separators according to the feeding method and tank structure type.

The mining direction of the downstream magnetic separator is the same as the rotation deviation of the cylinder (magnetic system). The fed slurry is directly under the drum (magnetic system), non-magnetic. Weak magnetic mineral particles are discharged from the gap between the two bottom plates under the drum, and the magnetic mineral particles are adsorbed to the outer surface of the downstream magnetic separator drum, and then rotate with the drum to the discharge area, where they are enriched into the concentrate tank.

Countercurrent magnetic separator means that the input direction of the pulp is opposite to the rotation angle of the drum. The pulp is directly conveyed to the bottom of the drum, non-magnetic. Weak magnetic minerals are discharged from the tailings hole on the bottom plate at the lower left corner, and the magnetic minerals are adsorbed to the reverse feeding direction of the cylinder, brought to the drain end, and discharged into the concentrate tank.

The semi-countercurrent magnetic separator is between forward flow and reverse flow. It can be said that it combines the advantages of both. While obtaining high-grade ore concentrate, it can also obtain a relatively high beneficiation recovery rate. Semi-countercurrent magnetic separators can run multiple units in series and parallel, and adopt multiple scanning and selection process schemes.