KR101522363B1 - method and apparatus for recovering iron from slag - Google Patents

Abstract

The present invention relates to a method and an apparatus to recover iron from slag and, more specifically, relates to a method and an apparatus to recover iron with ease and recycling the iron from the slag created during a steel-making process. The method to recover iron from the slag of the present invention comprises: a first grinding step to firstly grind the agglomerated slag created during the steel making process by placing it in the first grinder; a first granularity selection step to select a first group particle with a size of 0.1-5 mm, and a second group particle with a size of over 5 mm out of the materials ground during the above first grinding step; a first magnetic force selection step to select the magnetic particles from the above first group particles using the magnetic force; the second grinding step to secondly grind the above second group particles by placing it in the second grinder; a second granularity selection step to select a third group particles with the size of 0.1-5 mm from the materials ground during the above second grinding step; a third granularity selection step to select a fourth group particles with the size of 5-25 mm and a fifth group particles with the size of over 25 mm from the materials ground during the above second grinding step; a second magnetic force selection step to select the magnetic materials from the above fourth group particles using the magnetic force; a third magnetic force selection step to select the magnetic materials from an above fifth group particles using the magnetic force.

Description

[0001] METHOD AND APPARATUS FOR RECOVERING IRON FROM SLAG [0002]

The present invention relates to a method for recovering iron from slag and an iron recovery apparatus for the same, and more particularly, to an iron recovery method and a recovering apparatus capable of easily recovering and recycling iron from slag generated in a steelmaking or steelmaking process .

The steel industry consumes a large amount of raw materials and energy to produce steel, and it produces a large amount of various kinds of by-products and wastes through complicated connection production systems such as raw materials, milling, steelmaking and rolling. These by-products and wastes amount to 65% of steel, which is the main product. Of these, about 80% of the by-products and waste in solid state are slag, and the rest is generated in the form of dust or sludge.

Generally, slag generated in a steel mill is divided into blast furnace slag generated in a blast furnace process and steel slag generated in a steelmaking process. In addition, there are pre-treated slag generated in the pre-treatment process of steelmaking, slag generated in oxidation and reduction of electric furnace, refining furnace slag in stainless steel manufacturing process, and the like.

The slag thus discharged contains a large amount of iron powder. However, when the iron powder is recovered, it can still be usefully used as a source of iron. However, since the slag itself is difficult to find a particular application, the iron powder is recovered from the slag, Landfill or some other uses.

The iron recovery process uses a method of separating the slag and the iron powder by crushing the slag using the property that the adhesion between the slag as the mineral phase and the iron powder as the metal phase is not easy, and then attaching only the iron powder to the magnetic separator.

Korean Patent Laid-Open No. 10-2013-0058831 discloses an aggregate production apparatus capable of classifying iron-containing slag aggregates.

The present invention relates to a slag aggregate aggregate, and more particularly, to a slag aggregate slurry aggregate aggregate slurry aggregate aggregate slag aggregate aggregate slag aggregate aggregate slag aggregate aggregate slag aggregate slag aggregate slag aggregate A first conveying device for conveying the slag aggregate to the vibration discriminating device, and a magnetic separator disposed in the first conveying device for filtering out the iron content contained in the crushed slag aggregate.

However, since the above-described technique uses a jaw crusher as a crusher, it is difficult to finely crush the slag. Therefore, there is a problem that the content of iron is lowered because the shape of the pulverized particles is irregular, has a relatively large surface area, and has a rough surface shape.

Korean Patent Laid-Open No. 10-2013-0058831: Slag aggregate containing iron component capable of classifying aggregate manufacturing apparatus

It is an object of the present invention to provide a method for recovering iron from slag capable of recovering a large amount of recovered iron and finely grinding the slag, and an iron recovery apparatus for the same.

In order to accomplish the above object, there is provided a method for recovering iron from slag according to the present invention, comprising: a primary pulverizing step of charging a massive slag generated in a steelmaking or steelmaking process into a first mill, Wherein the pulverized material pulverized in the first pulverization step is subjected to a first boring step of selecting a first group particle having a size of 0.1 to 5 mm and a second group particle having a size of more than 5 mm; A primary magnetic force selecting step of selecting the cohesive particles from the first group particles by using a magnetic force; A second pulverizing step of putting the second group particles into a second pulverizer to secondarily pulverize the second group particles; Selecting a third group of particles having a size of 0.1 to 5 mm in the pulverized product in the second pulverization step; A third grouping step of sorting the fourth group particles having a size of 5 to 25 mm and the fifth group particles having a size of more than 25 mm in the pulverized product in the second pulverization step; A secondary magnetic force selecting step of selecting the coarse particles from the fourth group grains using a magnetic force; And a tertiary magnetic force selecting step of selecting the coarse particles from the fifth group particles by using a magnetic force.

Wherein the second pulverizing step of the second pulverizing step pulverizes the second group particles by a pulverizing medium flowing inside the rotating drum and separates the separated particles from the pulverizing medium by the pulverizing medium, And then charged into a second rotary mill to carry out the second milling step.

A first filtering unit formed at one side of the drum with a sieve having a size of 5 mm so as to discharge the third group particles to the outside of the drum and a second filtering unit disposed adjacent to the first filtering unit, And a second filtering unit formed of a sieve having a size of 25 mm so as to discharge the discharged water to the outside of the drum.

And a weight member for applying an impact to the massive slag is installed inside the first rotary pulverizer.

In order to accomplish the above object, the iron recovery apparatus from slag may be used to grind massive slag generated in a steelmaking or steelmaking process to first and second group particles having a size of 0.1 to 5 mm and larger than 5 mm A first mill; A first magnetic separator for sorting the particles by applying a magnetic force to the first group particles discharged from the first pulverizer; A third group particle having a size of 0.1 to 5 mm while having the second group particles discharged from the first mill are secondarily pulverized using the adhered particles selected by the first magnetic separator as a pulverizing medium, A second grinder for selecting a fifth group particle having a diameter of more than 25 mm; A second magnetic separator for sorting the particles by applying a magnetic force to the fourth group particles discharged from the second pulverizer; And a third magnetic separator for sorting the particles by applying a magnetic force to the fifth group particles discharged from the second pulverizer.

The first pulverizer includes a cylindrical drum having an inlet formed at one side thereof and an outlet formed at the other side thereof, a driving part for rotating the drum, and a body formed adjacent to the discharge port side of the drum and having an eye size of 5 mm, And a spherical weight member which hits the inside of the drum to collide with the massive slag injected into the drum and impacts.

As described above, the present invention can finely grind slag by using the first and second mills to easily separate the particles by size, and the recovery rate of iron is high by selecting the magnetic force of each particle separated by size. In addition, a large amount of recovered water can be processed in a continuous operation process.

1 is a block diagram showing a method of recovering iron from slag of the present invention,
FIG. 2 is a schematic view showing the iron recovery apparatus applied to FIG. 1; FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an iron recovery method and an iron recovery apparatus according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 and 2, a method for recovering iron from slag according to an embodiment of the present invention includes a first crushing step, a first boring selecting step, a first magnetic force selecting step, a second crushing step, and a second crushing step A boring degree selection step, a third borrowing degree selection step, a second magnetic force selection step, and a third magnetic force selection step. Each step will be examined in detail.

1. Primary grinding step

First, in the first pulverization step, the massive slag is charged into the first pulverizer (10) and pulverized first.

The slag used in the present invention is a slag generated in a steel making process or a steel making process of a steel mill. Slag generated in steel mills is divided into blast furnace slag generated in blast furnace and steel slag generated in steelmaking process. In addition, there are pre-treated slag generated in the pre-treatment process of steelmaking, and slag generated in oxidation and reduction of electric furnace. The slags can be applied to all of the present invention.

The slag to be crushed is kept in a certain place and then introduced into the hopper (1). The slag injected into the hopper 1 may be a mixture of massive slag of various sizes. In this case, bulk slag of about 10 mm or more can be included. For example, bulk slags of 10 to 200 mm in size are included.

As a pretreatment process before charging the hopper 1, the massive slag can be passed through a conventional magnetic separator. In this case, only the cohesive slag having a high iron content can be put into the hopper 1.

A rotary mill can be used as the first mill. The first crusher 10 is composed of a cylindrical drum 11 and a driving unit for rotating the drum 11. Although not shown, the driving unit may be a driving motor connected to the drum and a chain or belt or gear.

The drum 11 has an inlet through which the slag flows into one side and an outlet through which the pulverized slag can be discharged from the other side. The outlet is provided with a door that can open and close the outlet.

The drum 11 is installed so that one side where the inlet is formed is higher than the other side where the outlet is formed. A plurality of ribs (not shown) can be formed on the inner circumferential surface of the drum 11 at predetermined intervals in the left-right direction. The ribs are formed protruding in the direction of the rotation center of the drum 11. Therefore, when the drum 11 rotates, the slag does not slide along the inner circumferential surface of the drum 11 but goes up to a certain height and then falls downward, so that the crushing effect of the slag can be enhanced.

In order to prevent the wear of the drum 11, one or more liner may be provided on the inner circumferential surface of the drum.

Inside the drum 11, the slag is crushed by collision with each other and collision with the inner circumferential surface of the drum 11. In order to increase the crushing effect, a weight member 13 capable of impacting the slag is provided inside the drum 11. It is preferable that the weight member 13 is formed of a metal material having a large specific gravity and excellent strength. The weight member 13 may be formed in a spherical shape. At least one weight member 13 is provided in the drum 11. The weight member 13 can be connected to the wire 14 provided on the inner circumferential surface of the drum 11. When the drum 11 rotates, the weight member 13 collides with the slag while flowing inside the drum 11, and crushes the slag finely.

On the side of the drum 11, a filtering section 15 is formed. The filtering section (15) is provided adjacent to the discharge port side. The filtering section 15 is formed as a body having an eye size of 5 mm. This is to select a slag having a particle size of 5 mm or less among the pulverized slag pulverized in the drum 11.

The slag discharged from the hopper 1 and conveyed through the conveying conveyor 5 is introduced into the drum 11 of the first crusher 10. Inside the rotating drum 11, the slag is pulverized and gradually moved toward the discharge port.

2. a step of selecting the first borrowing;

The first-order inlet sorting step selects the crushed slag from the first crusher as a first group of particles having a size of 0.1 to 5 mm and the second group of particles having a size of more than 5 mm. This primary input selection process is performed through the filtering unit 15 installed in the drum 11. [

That is, the slag injected into the drum 11 is crushed and gradually moved toward the discharge port. Then, the slag pulverized material having a size of 0.1 to 5 mm is discharged to the outside of the drum 11 through the sieve. At this time, the discharged first group grains fall on the chute 20 provided at the lower portion of the filtering section 15 and are stored in the chute.

On the other hand, the second group particles exceeding 5 mm remain inside the drum 11 and are discharged to the outside through the opening of the door.

3. Primary magnetic force selection stage

The first group of particles are stored in the chute 20 and then discharged to the conveying conveyor 50. The first group particles conveyed by the conveying conveyor 50 are separated from the first magnetic separator 55 by the high-iron content cohesive particles and the low-iron content non-magnetic particles.

A conventional one can be used as the first magnetic force selector. The illustrated first magnetic force separator 55 includes a magnetic belt 57 for generating magnetic force, a plurality of rollers 59 for supporting the magnetic belt 57 and a magnetic belt 57 for contacting the magnetic particles 57, And a scrubber (not shown) for separating the gas. The magnetic belt 57 is moved in an endless track by the roller 59 and attaches only the iron-rich particles among the first group of particles conveyed through the conveying conveyor. Adhered particles adhered to the magnetic belt 57 are separated by a scrubber and stored in a separate storage device. The separated 5 mm or less adhered particles are used as a pulverizing medium in a second pulverization step to be described later. The non-magnetic particles having a low iron content of 5 mm or less are stored in the chute 60 installed on one side of the conveying conveyor 50. These non-magnetic particles can be used as aggregates of 5 mm or less.

4. 2nd crushing step

The second grinding step is a step of putting the second group particles discharged from the first grinder 10 into the second grinder 30 and pulverizing them in a second order. The second crusher (30) is installed adjacent to the outlet of the first crusher (10).

The second crusher 30 finely crushes the second group of particles by the crushing medium flowing inside the rotating drum 31.

The second crusher 30 is composed of a cylindrical drum 31 and a driving unit for rotating the drum 31. Although not shown, the driving unit may be a driving motor connected to the drum and a chain or belt or gear.

Although not shown, an inlet is formed in the drum 31 to allow the slag to be introduced into one side, and an outlet is formed in the other side to discharge the pulverized slag. A door (not shown) is installed at the inlet and outlet, respectively.

The drum 31 is installed so that one side where the inlet is formed is high and the other side where the outlet is formed is inclined. In order to prevent the wear of the drum 31, one or more liners may be provided on the inner circumferential surface of the drum 31.

The drum 31 is provided with a first filtering section 35 and a second filtering section 37, respectively.

The first filtering section 35 is formed as a body having an eye size of 5 mm. The second filtering section 37 is formed of a sieve having a size of 25 mm. The second filtering section 37 is provided adjacent to the first filtering section 35.

The pulverized medium for pulverizing the second group particles introduced into the drum 31 uses the particles separated in the first magnetic force selecting step. The selected particles in the primary magnetic force selecting step are 0.1 to 5 mm in size and have a very high strength. In addition, it is spheronized in the process of pulverization in the first crusher 10, and is formed into a spherical shape. Therefore, such adherent particles can be used as a bulk material of a ball used in a conventional crusher.

Adhesive particles having a diameter of 5 mm or less inserted into the second mill 30 easily cause desorption of the non-adherent components formed on the surface of the second group grains while causing a countless collision with the second group grains.

Adhesive particles of 5 mm or less used as a milling medium can be injected into the drum 31 through a nozzle 33 provided inside the drum 31. In this case, the adhered particles can be injected into the drum 31 at a constant speed using air pressure.

The second group particles discharged from the first crusher (10) are introduced into the second crusher (30) through the inlet of the second crusher (30). When a certain amount of the second group particles is injected into the second mill 30, the drum 31 is rotated while the door of the inlet is closed to crush the second group particles. At this time, the inside of the drum 310 collides with the second group of particles while spraying particles of 5 mm or less as the pulverizing medium.

The second group grains are finely crushed in the drum 31 and gradually move toward the discharge port.

5. Step for Selecting 2 Lines

The second borrowing step selects a third group of particles having a size of 0.1 to 5 mm in the pulverized product in the second pulverizing step. This sorting process is performed through the first filtering section 35 provided on the drum 31. [

That is, within the drum 31, the second group particle is gradually pulverized and moves gradually toward the discharge port. Then, the slag crushed material having a size of 5 mm or less is discharged to the outside of the drum 31 through the sieve. The slag pulverized material discharged to the outside through the first compaction section (35) is a third group particle. The third group of particles fall on the chute 40 provided below the first filtering portion 35. The third group of particles collected in the chute 40 is again introduced into the second crusher 30 and used as a crushing medium. In this case, the third group particle before the introduction into the second mill is separated into the non-magnetic particles having a high content of iron and the non-magnetic particles having a high content of iron, and then only the particles of the third group can be introduced into the second pulverizer.

6. The step of selecting the third borrowing;

The third boring degree sorting step is performed through the second kneading section 37 provided on the drum 31. The slag crushed material that has passed through the first compaction section 35 and reaches the second compaction section 37 is particles having a size of 5 mm or more. These particles are sorted through a second filtering section 37 into a fourth group particle having a size of 5 to 25 mm and a fifth group particle having a size of more than 25 mm. That is, the fourth group particles having a size of 5 to 25 mm pass through the sieve of the second filtering section 37 and are discharged to the outside of the drum 31. At this time, the discharged fourth group particles fall on the chute 45 provided below the second filtering portion 37.

On the other hand, the fifth group particles exceeding 25 mm remain in the drum 31 to the end and are discharged to the outside through the discharge port.

7. Second magnetic force selection stage

The fourth group grains discharged from the drum 31 are stored in the chute 45 and then discharged to the conveying conveyor 70. The fourth group particles conveyed by the conveying conveyor 70 are separated from the second magnetic separator 75 by the high-iron content cohesive particles and the low-iron content non-magnetic particles.

The second magnetic force selector (75) is identical in construction to the first magnetic force selector (55). Therefore, the magnetic belt is attached to only the particles having a high iron content among the fourth group particles which are conveyed through the conveying conveyor while traveling in an endless track. Adhered particles attached to the magnetic belt are separated by a scrubber and stored in a separate storage device. Adhesive particles of 5 to 25 mm apart are the final objects to be recovered in the present invention. The separated 5 to 25 mm of the adhered particles have an iron component content of about 60 to 90% by weight and are put into a steel making process.

And the 5 to 25 mm non-magnetic particles having a low iron content are stored in the chute 80 installed on one side of the conveying conveyor 70. These nonmagnetic particles can be used as aggregates of 5 to 25 mm.

8. Third magnetic force selection stage

The fifth group particle discharged to the outside through the discharge port of the drum 31 is conveyed by the conveying conveyor 90. [ The fifth group particles conveyed by the conveying conveyor 90 are separated by the third magnetic separator 95 into the non-magnetic particles having a high iron content and the non-magnetic particles having a low iron content.

The third magnetic force selector 95 has the same configuration as the first magnetic force selector 55. Therefore, the magnetic belt is attached to only the particles of high iron content among the fifth group particles that are conveyed through the conveying conveyor 90 while traveling in an endless track. Adhered particles attached to the magnetic belt are separated by a scrubber and stored in a separate storage device. Separated 25 mm excess adherent particles are the final objects to be recovered in the present invention. The separated 25 mm-thick adherent particles have an iron component content of about 60 to 90% by weight, and are put into a steel making process.

And, the non-magnetic particles exceeding 25 mm in which the iron content is low are stored in the chute 100 installed on one side of the conveying conveyor 90. These non-magnetic particles can be used as aggregates of more than 25 mm.

As described above, according to the present invention, it is possible to finely grind slag by using the first and second mills to easily separate the particles by size, and the recovery rate of iron is high by selecting the magnetic force of each particle separated by size. In addition, a large amount of recovered water can be processed in a continuous operation process.

On the other hand, the first and second pulverizers may be integrally formed as shown in FIG. That is, a partition for bisecting one drum is provided. The drum in the left space is used as the first crusher with respect to the partition, and the drum in the right space is used as the second crusher. At this time, the door is provided on the partition wall, and the slag crushed in the first crusher is introduced into the second crusher through the door opening.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, and that various modifications and equivalent embodiments may be made by those skilled in the art. Accordingly, the true scope of protection of the present invention should be determined only by the appended claims.

1: hopper 10: first crusher
20: Chute 30: Second crusher
35: first filtering section 37: second filtering section
55: magnetic separator

Claims (6)

delete A primary pulverizing step of pulverizing primary slag produced in a steelmaking or steelmaking process into a primary pulverizer;
Wherein the pulverized material pulverized in the first pulverization step is subjected to a first boring step of selecting a first group particle having a size of 0.1 to 5 mm and a second group particle having a size of more than 5 mm;
A primary magnetic force selecting step of selecting the cohesive particles from the first group particles by using a magnetic force;
A second pulverizing step of putting the second group particles into a second pulverizer to secondarily pulverize the second group particles;
Selecting a third group of particles having a size of 0.1 to 5 mm in the pulverized product in the second pulverization step;
A third grouping step of sorting the fourth group particles having a size of 5 to 25 mm and the fifth group particles having a size of more than 25 mm in the pulverized product in the second pulverization step;
A secondary magnetic force selecting step of selecting the coarse particles from the fourth group grains using a magnetic force;
And a tertiary magnetic force selecting step of selecting the coarse particles from the fifth group particle by using a magnetic force,
The second mill of the second milling step pulverizing the second group of granules by a milling media flowing inside the rotating drum,
And the secondary pulverization step is carried out by injecting the adhered particles selected in the primary magnetic force selection step into the second pulverizer with the pulverizing medium. The drum washing machine according to claim 2, wherein the drum has a first filtering part formed in a shape of 5 mm in size so that the third group particles can be discharged to the outside of the drum, And a second filtering unit formed of a sieve having a size of 25 mm so that the fourth group particles can be discharged to the outside of the drum. A primary pulverizing step of pulverizing primary slag produced in a steelmaking or steelmaking process into a primary pulverizer;
Wherein the pulverized material pulverized in the first pulverization step is subjected to a first boring step of selecting a first group particle having a size of 0.1 to 5 mm and a second group particle having a size of more than 5 mm;
A primary magnetic force selecting step of selecting the cohesive particles from the first group particles by using a magnetic force;
A second pulverizing step of putting the second group particles into a second pulverizer to secondarily pulverize the second group particles;
Selecting a third group of particles having a size of 0.1 to 5 mm in the pulverized product in the second pulverization step;
A third grouping step of sorting the fourth group particles having a size of 5 to 25 mm and the fifth group particles having a size of more than 25 mm in the pulverized product in the second pulverization step;
A secondary magnetic force selecting step of selecting the coarse particles from the fourth group grains using a magnetic force;
And a tertiary magnetic force selecting step of selecting the coarse particles from the fifth group particle by using a magnetic force,
Wherein a weight member for applying an impact to the massive slag is provided in the first mill. delete A first grinder for sorting first group particles having a size of 0.1 to 5 mm and second group particles having a size of more than 5 mm while pulverizing the massive slag generated in a steelmaking or steelmaking process;
A first magnetic separator for sorting the particles by applying a magnetic force to the first group particles discharged from the first pulverizer;
A third group particle having a size of 0.1 to 5 mm while having the second group particles discharged from the first mill are secondarily pulverized using the adhered particles selected by the first magnetic separator as a pulverizing medium, A second grinder for selecting a fifth group particle having a diameter of more than 25 mm;
A second magnetic separator for sorting the particles by applying a magnetic force to the fourth group particles discharged from the second pulverizer;
And a third magnetic force sorter for sorting the particles by applying magnetic force to the fifth group particles discharged from the second pulverizer,
The first pulverizer includes a cylindrical drum having an inlet formed at one side thereof and an outlet formed at the other side thereof, a driving part for rotating the drum, and a body formed adjacent to the discharge port side of the drum and having an eye size of 5 mm, And a spherical weight member which hits the inside of the drum to impinge on the massive slag injected into the drum and impacts the slag. .

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