RU1787551C - Electromagnetic separator - Google Patents

Abstract

Usage: separation of materials in a magnetic field, removal of ferromagnetic inclusions from the flow of multicomponent bulk materials in the coal, construction, food and other industries. SUMMARY OF THE INVENTION: An electromagnetic separator consists of pole pieces 1 and 2, a frame of magnetic wire 3. The surfaces of the pole pieces have a toothed shape 4 and 5, and the vertices are directed toward the material being processed. The pole piece 1 is mounted above the conveyor belt transporting the material, and the pole piece 2 above the exit sheet of the conveyor belt from the drum 8 to extract ferromagnetic inclusions from the freely falling stream of the transported material. The separator has a flat magnetic wire 6, located under the upper branch of the belt 7 of the conveyor belt, covering the drum 8. 2 il.

Description

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The invention relates to devices for separating materials in a magnetic field and can be used to remove ferromagnetic inclusions from a stream of multicomponent mixtures, for example, in the food industry.

Known electromagnetic iron, including the electromagnetic system, a wedge-shaped induction pole, made in the form of a set of magnetic plates, separated by gaskets of non-magnetic material.

The disadvantage of this design is the low efficiency of the extraction of ferromagnetic particles from bulk material, due to the fact that the force created by the magnetic field and acting on the ferromagnetic particle is directed to the wedge-shaped inductor pole and presses it to the surface of the tape, which prevents the extraction of ferromagnetic particles from multicomponent mixtures.

An electromagnetic separator is known, consisting of a conveyor belt, a magnetic system with pole pieces located at an angle to the vertical and with mating faces placed parallel to the horizon and made with sharp edges.

The disadvantage of this design is the low efficiency of the extraction of ferromagnetic particles from the bulk material, since in this design there are only two working faces on the pole pieces, the surfaces of which remove the ferromagnetic particles from the bulk material.

An electromagnetic separator adopted for the prototype is also known, which contains an electromagnetic system including a main magnetic circuit, in the grooves of which the main and additional windings and an additional magnetic circuit are laid, in the grooves of which the winding is laid, as well as a transporting body with a conveyor, a metal detector and a receiver of extracted metal objects.

The disadvantage of this design is that the main and additional magnetic circuits are located above the freely falling stream of the transported material, which excludes the passage of the magnetic flux through the multicomponent mixture located on the upper branch of the conveyor belt and removing ferromagnetic inclusions from it.

This is due to the fact that the main part of the magnetic flux created by the windings of the main and additional magnetic wires closes in close proximity to them, which reduces the region

the action of magnetic forces extracting ferromagnetic particles from the mixture.

In addition, in the design adopted for the prototype, the surfaces of the main and additional magnetic circuits facing the freely falling stream of the transported material do not have a gear shape, i.e. create the necessary magnitude of the magnetic attraction due to the magnetic field gradient, which may be insufficient to extract ferromagnetic inclusions from multicomponent mixtures.

The purpose of the invention is to increase the efficiency of extracting ferromagnetic inclusions from bulk material.

This goal is achieved by the fact that in an electromagnetic separator comprising an electromagnetic system with pole pieces, one of which is located above the place where the conveyor belt leaves the drum, to extract ferromagnetic inclusions from the freely falling stream of transported material,

5 according to the invention, another pole piece is mounted above the conveyor belt conveying the material, while the separator is equipped with a flat magnetic wire located underneath the upper

0 by the branch of the belt at the location of the other pole piece, the surfaces of the pole pieces being serrated, the vertices of which are directed to the surface of the material being processed, which allows ferromagnetic inclusions to move several times in the zone of action of the gradient forces created by magnetic by the field.

0 The efficiency of extracting ferromagnetic inclusions from bulk material will depend on the number of prongs made on the pole pieces.

5 in FIG. 1 shows a ferromagnetic particle A moving with under a pole piece on which 4 teeth are made and the distribution of the magnetic field beneath it. Moving with conveyor belt.

Particle A is subjected to the action of gradient forces created by the magnetic field four times, which leads to a high probability of its extraction from the bulk mixture. In FIG. 2 presents the design

5 electromagnetic separator. It consists of pole pieces 1 and 2, fixed to the core of the magnetic circuit 3, the surfaces of which have a toothed shape 4 and 5, and the vertices are directed to the material being processed. Performance

of the surfaces of the pole pieces 1 and 2 with gears 4 and 5, allows you to create an inhomogeneous magnetic field in the zone of passage of bulk material and thereby increase the force acting on the ferromagnetic particle. The implementation of multi-pointed peaks allows the creation of several inhomogeneous zones where a force is applied to extract the particle from the bulk material. To increase the working magnetic flux, a flat magnetic circuit 6 is located under the upper branch of the tape 7, covering the drum 8, made of magnetic material and which is part of the magnetic circuit.

The magnetic flux generated by the electromagnet closes along the path: pole tip 1, teeth 4, flat magnetic circuit 6, drum 8. teeth 5, pole 2, pmo 3.

The magnetic force created by the electromagnet field is directed towards the teeth and tends to attract particles to them. As the magnetic material for the magnetic circuit can be used steel grades: St 0, St 3, St 5, Steel 10. Steel 20 and others.

The operation of the electromagnetic separator is as follows.

A multicomponent bulk mixture with ferromagnetic inclusions moves along the upper branch of the conveyor belt 7. When passing under the prong of an electromagnetic separator, a force acts on each ferromagnetic particle:

F // oMvH where Ts0 4 Gn / m is the magnetic constant:

 particle magnetization; vH is the magnetic field gradient.

This force tends to remove the ferromagnetic particle from the multicomponent mixture and draw it to the teeth. In FIG. Figure 1 shows the passage of a ferromagnetic particle A along a conveyor belt under the serrated surface of the pole piece 2. As can be seen from the field distribution pattern, the maximum magnetic field strength occurs under the tip of the tooth. In our case, particle A passes four times over the sections where the intensity and gradient of the magnetic field are maximum. Thus, a ferromagnetic particle is attracted to the teeth immediately or moves in a loose multicomponent mixture closer to its surface when moving together with the conveyor belt from one tooth to another. The extraction efficiency of a ferromagnetic particle depends both on its magnetization, which can be increased by increasing

the maximum magnetic field strength due to the placement of a flat magnetic circuit in the space between the conveyor belts, which leads to a decrease in the magnetic resistance on the path of the working flux, and due to making the surfaces of the pole pieces multi-pronged, which allows you to create several gradient zones for the extraction of ferromagnetic particles.

The ferromagnetic inclusions remaining in the granular mixture are removed from it by the pole tip 1, from the freely falling flow of the granular material upon transition from the conveyor belt 7 to the conveyor belt 9. Moreover, the ferromagnetic inclusions repeatedly fall into the gradient zones located under each of the tooth tips, which increases the efficiency extracting them from the multicomponent mixture.

When a large number of ferromagnetic particles accumulate on the teeth of the pole pieces, the electromagnet is disconnected from the power source, the magnetization system is demagnetized and the ferromagnetic particles are cleaned with a scraper or brush.

The efficiency of such magnetic separators is 3–10 times higher than the currently known magnetic separators, which is confirmed by their tests. The proposed design of an electromagnetic separator is expediently used, for example, in the food industry for the extraction of ferromagnetic particles from heavy flour.

Claims (1)

SUMMARY OF THE INVENTION An electromagnetic separator comprising an electromagnetic system with pole tips, one of which is located above the exit of the conveyor belt from the drum to extract ferromagnetic inclusions from the freely falling stream of transported material, characterized in that, in order to improve extraction efficiency, the other pole tip is mounted above conveyor belt transporting material, while the separator is equipped with a flat magnetic circuit located under the upper branch of the conveyor tape at the location of the other pole piece, the surfaces of the pole pieces being serrated, the tips of the teeth of which are directed towards the surface of the material being processed. Phi B.I