JPH0975774A - Magnetic separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic separator in which magnetic separation efficiency is prevented from lowering due to the coexistence of granular substances of differential particle size in magnetic separators in which granular substances are made to fall into a magnetic field to separate them by differences in magnetic susceptibility. SOLUTION: In a magnetic separator, pulverized coal consisting of particles 3, 5 of organic matter of small magnetic susceptibility and particles 4, 6 of sulfur and ash of large magnetic susceptibility is made to fall into a magnetic field and is separated by differences in magnetic susceptibility. The pulverized coal to be separated is classified by a classifier 7 for separating it every particle size of the same order, and two magnetic separators 1, 1 for magnetically separating the classified granular substances every particle size are installed. A device of such constitution that a pulverizer for pulverizing the pulverized coal to be magnetically separated to particle size of high separation efficiency is provided is also provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic separation device in which a powder or granular material is dropped into a magnetic field and separated according to a difference in magnetic susceptibility.

[0002]

2. Description of the Related Art Materials each have a unique magnetic susceptibility and can be separated by utilizing the difference in magnetic susceptibility. FIG. 4 shows a conventional example of a magnetic separation device based on this principle. A magnetic field gradient is generated in the magnetic separation unit 1 by providing the magnetic field generation device 2 outside the magnetic separation unit 1.

When the powder particles are dropped from the supply unit 10 into this magnetic field, the small-diameter particles 4 and the large-diameter particles 6 of the powder particles having a high magnetic susceptibility are outwardly moved in the magnetic separation unit 1 by the magnetic field gradient. The track is bent outward due to the magnetic force. On the other hand, the small-diameter particles 3 and the large-diameter particles 5 having a small magnetic susceptibility do not receive a magnetic force or only a weak magnetic force, and therefore their trajectories do not change.

As a result, in the downstream portion of the magnetic separation device, the particles 4 and 6 having a high magnetic susceptibility gather in the outer portion, and the particles 3 and 5 having a low magnetic susceptibility gather near the center. Here, the collecting portion 12 for the particles 4 and 6 having a high magnetic susceptibility and the particles 3 and 5 having a low magnetic susceptibility are used.
The respective particles are separated and collected by providing the collecting unit 11 of. The above-mentioned conventional techniques are in the stage of being examined at the laboratory level.

[0005]

In the prior art, there were the following problems because particles having a large particle size and particles having a small particle size were simultaneously supplied to the magnetic separation device.

(1) Large particles collide with small particles,
Due to this, the particles having a large magnetic susceptibility and the particles having a small magnetic susceptibility agglomerate to reduce the magnetic separation efficiency.

(2) In magnetic separation, as shown in FIG. 3, there is an optimum particle size that maximizes the separation efficiency at a certain particle size. However, in the prior art, the particles are supplied to the magnetic separation section in a non-uniform size. Since there are many particles having a particle diameter far from the optimum particle diameter, the separation efficiency decreases.

According to the present invention, in a magnetic separation device in which powder particles are dropped into a magnetic field and separated according to the difference in magnetic susceptibility, the powder particles having different particle diameters are mixed to reduce the magnetic separation efficiency. It is an object of the present invention to provide a magnetic separation device that prevents the above.

[0009]

In order to solve the above-mentioned problems in a magnetic separation device in which a powder or granular material is dropped into a magnetic field and separated according to the difference in magnetic susceptibility, the present invention provides the following (1) and ( Adopt the configuration of 2).

(1) A classifier for separating powders and granules to be magnetically separated into particles of similar size, and a magnetic separation for magnetically separating the powders and granules of each particle size classified by the classifier. With a machine.

(2) A structure provided with a crusher for crushing powder particles to be magnetically separated into particles having high separation efficiency.

In the magnetic separation device having the above-mentioned configuration (1), the particles to be separated are divided into particles of approximately the same size by the classifier before being supplied to the magnetic separation section, and then, respectively. It is supplied to the magnetic separation unit for each of the particles having the particle size of.

Since the powder particles thus supplied have the same particle size, it is possible to prevent a decrease in separation efficiency due to collision or agglomeration that occurs when particles having different particle sizes are magnetically separated at the same time. it can.

On the other hand, the powder particles to be magnetically separated have an optimum particle size that maximizes the separation efficiency depending on the particle size of the particles to be separated. This optimum particle size differs depending on the type of particles to be separated, and each has a unique value.

Therefore, according to the above-mentioned constitution (2), particles having different particle diameters are made into particles having the same size as the optimum particle diameter of the target particles by the pulverizer and supplied to the magnetic separation section, so that the separation efficiency is high. Separation can be performed.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION A magnetic separator according to the present invention will be specifically described below based on the illustrated embodiments. In the following embodiments, the same components as those of the conventional device shown in FIG. 4 are designated by the same reference numerals for simplification of description.

(First Embodiment) First, an apparatus according to the first embodiment shown in FIG. 1 will be described. In FIG. 1, 7 is a classifier for classifying powder particles to be magnetically separated into small particle particles 3 and 4 and large particle particles 5 and 6. 8 is a transfer part.

In this embodiment, the granular material to be separated is pulverized coal, and the pulverized coal which is the particle to be separated is an organic substance which is an effective component (which has a small magnetic susceptibility, so in FIG.
Particles (corresponding to particles 3 and 5) and sulfur / ash (having a relatively large magnetic susceptibility and corresponding to particles 4 and 6 in FIG. 1).

Sulfur / ash particles 4 and 6 having high magnetic susceptibility
The falling trajectory is bent outward due to the influence of the magnetic field and magnetic field gradient generated by the magnetic generator 2 in the magnetic separation unit 1. Since the magnetic susceptibility of one of the organic particles 3 and 5 is small, the influence of the magnetic field and magnetic field gradient is large. It can be separated because it falls almost directly below without receiving it.

The size of the pulverized coal particles to be separated is such that particles of various sizes are mixed up to a maximum particle size of about 1 mm. In this state, when magnetic separation is performed in the magnetic separation unit 1, the organic particles 3 and 5 having different particle sizes and the particles 4 and 6 of sulfur and ash collide and aggregate, so that the separation efficiency is not good.

Therefore, before supplying pulverized coal to the magnetic separation unit 1 as in the apparatus shown in FIG. 1, particles of the same size are divided by the classifier 7 into sizes and supplied to the magnetic separation unit 1. It is possible to prevent collision and agglomeration of the organic particles 3 and 5 and the sulfur / ash particles 4 and 6 which are generated due to the difference, and to improve the separation efficiency.

(Second Embodiment) Next, an apparatus according to the second embodiment shown in FIG. 2 will be described. In FIG. 2, a crusher 9 functions to crush the pulverized coal to be separated into particles having a desired particle size.

In magnetic separation, as shown in FIG. 3, there is an optimum particle size that maximizes the separation efficiency depending on the particle size of the particles to be separated. This optimum particle size differs depending on the type of particles to be separated, and each has a unique value.

Therefore, as in the apparatus shown in FIG. 2, particles having different particle sizes are made uniform by the crusher 9 into particles having a size similar to the optimum particle size of the target particles and are supplied to the magnetic separation section 1. Separation can be performed with high separation efficiency.

That is, since particles of various sizes are present in the pulverized coal, if it is supplied to the magnetic separation unit as it is, the separation efficiency is low. Therefore, a pulverizer 9 is installed upstream of supplying pulverized coal to the magnetic separation unit 1 to pulverize pulverized coal having various particle sizes into a particle size having a maximum separation efficiency and supply the pulverized coal to the magnetic separation unit. Of.

The present invention has been specifically described above based on the illustrated embodiments, but the present invention is not limited to these embodiments, and various configurations are possible within the scope of the present invention shown in the claims. It goes without saying that changes may be made.

For example, in the first embodiment, the pulverized coal is classified into two particle groups, but this may be classified into three or more particles and magnetic separation may be performed for each particle. Good.

[0028]

As described above, according to the magnetic separation apparatus of the present invention, a classifier that separates powder particles to be magnetically separated into particles of similar size, and a classifier that classifies the particles. By having a magnetic separator that magnetically separates powder particles of different particle sizes, it is possible to avoid collisions and agglomeration between particles that occur due to the difference in particle size of the objects to be separated, and improve magnetic separation efficiency. be able to.

Further, according to the present invention, in the constitution in which the pulverizer for pulverizing the granular material to be magnetically separated into the particle diameter having the high separation efficiency is provided, the particle sizes can be made to be near the optimum particle diameter. The separation efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a magnetic separation device according to a first embodiment of the present invention.

FIG. 2 is a conceptual diagram of a magnetic separation device according to a second embodiment of the present invention.

FIG. 3 is an explanatory diagram of a relationship between a magnetic separation efficiency of powder and granular material and an optimum particle diameter.

FIG. 4 is a conceptual diagram of a magnetic separation device according to a conventional example.

[Explanation of symbols]

 1 Magnetic Separation Part 2 Magnetic Field Generator 3 Particles with Small Magnetic Susceptibility (Small Particle Size) 4 Particles with Large Magnetic Susceptibility (Small Particle Size) 5 Particles with Small Magnetic Susceptibility (Large Particle Size) 6 Particles with Large Magnetic Susceptibility (Large Particle) Diameter 7 Classifier 8 Transfer device 9 Crusher 10 Supply unit 11 Recovery unit for particles with low magnetic susceptibility 12 Recovery unit for particles with high magnetic susceptibility

Claims (2)

[Claims] 1. A magnetic separation device in which a powder or granular material is dropped into a magnetic field and separated according to a difference in magnetic susceptibility,
Characterized by having a classifier that separates the particles to be magnetically separated into particles of similar size, and a magnetic separator that magnetically separates the particles of each particle size that have been classified by the classifier. And a magnetic separation device. 2. A magnetic separation device in which powder particles are dropped into a magnetic field and separated according to the difference in magnetic susceptibility,
A magnetic separation device comprising a crusher for crushing the particles to be magnetically separated into particles having high separation efficiency.