JP2001212476A - Method for recovering valuable material from used graphite-containing refractory brick - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for recovering valuable materials from used graphite-containing refractory bricks which cost effectively recovers the valuable materials from the used graphite-containing refractory bricks which are heretofore not recycled, for example, bricks stuck with slag and bricks of composite type, without discarding these bricks. SOLUTION: The graphite-containing refractory bricks stuck with the slag and/or metal by use are subjected to a crushing treatment in such a manner that the bricks are mainly composed of grains. The magnetized materials included in the crushed graphite-containing refractory bricks are subjected to a magnetic separation treatment and are thereby removed from the graphite-containing refractory bricks and, thereafter, the graphite-containing refractory bricks subjected to the magnetic separation treatment are classified to heavy materials mainly composed of the valuable materials and lightweight materials mainly composed of the slag by gravity sorting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a used graphite-containing refractory for economically recovering valuable materials from used graphite-containing refractory bricks, such as slag-attached bricks and composite type bricks, which have not been reused. The present invention relates to a method for recovering valuable resources from bricks.

[0002]

2. Description of the Related Art Conventionally, it has been studied to use a used graphite-containing refractory brick as a raw material of a refractory for effective utilization of resources. Therefore, Japanese Patent Application Laid-Open No. 3-7525
As described in JP-A-5, graphite-containing refractory bricks are placed in a cylindrical or conical rotating container and the inner volume ratio of the container is set to 70%.
Fill the container below, and fill the container with a critical rotation speed of 5 to 5
While rotating at 0%, the inside of the container is made to be a high-temperature oxidizing atmosphere, and the graphite or the contained combustion component in the graphite-containing refractory is ashed, so that valuables in the graphite-containing refractory, that is, MgO or C
A method for extracting aO and the like is shown. However, this method has problems in that the apparatus for heating the rotating container becomes large and that energy cost is required. Therefore, as described in Japanese Patent Application Laid-Open No. 9-328354, the infiltrated portion or attached portion of the used graphite-containing refractory brick such as metal and slag is removed in advance, coarsely crushed, and friction is applied to the coarsely crushed particles. Methods have been proposed for applying force, pressing force and / or impact force. As a result, valuable materials, such as MgO, are separated from the graphite, collected, and reused as a refractory raw material.

[0003]

However, the above method has the following problems to be solved. Since the used graphite-containing refractory brick to be treated has previously removed portions where metal or slag has penetrated or adhered, the amount of valuable resources that can be collected is smaller than when all the bricks were treated. In addition, the valuable resources after recovery have the same fine particles as graphite-containing refractory bricks that contained valuable resources because the fine powder of the matrix portion of graphite-containing refractory bricks slightly adhered to the surface. Often used as a recycled material for graphite-containing refractory bricks having a composition, it has been difficult to use it for other purposes. The present invention has been made in view of such circumstances, without discarding used graphite-containing refractory bricks that have not been reused, for example, slag-attached bricks and composite-type bricks, economically recyclable valuables in the bricks. The purpose of the present invention is to provide a method for recovering valuable materials from used graphite-containing refractory bricks which can be used not only as a raw material for refractory bricks containing graphite but also as a raw material for paints and mold release agents. I do.

[0004]

According to the present invention, there is provided a method of recovering valuable materials from used graphite-containing refractory bricks according to the present invention. After crushing the graphite-containing refractory brick, the magnetized material contained in the crushed graphite-containing refractory brick is removed from the graphite-containing refractory brick by magnetic separation treatment. And slag as a main component. As described above, since the graphite-containing refractory brick is subjected to the crushing treatment so as to be mainly composed of particles, the specific gravity can be easily separated. . In addition, graphite-containing refractory bricks to which slag and / or metal has adhered have conventionally been subjected to manual removal of slag or discarded. It becomes possible to collect and reuse heavy materials mainly composed of valuable materials from the contained refractory bricks.

[0005] In the method for recovering valuable materials from used graphite-containing refractory bricks according to the present invention, the graphite-containing refractory brick is preferably composed mainly of alumina graphite and zirconia graphite, and the heavy material is preferably composed of zirconia graphite. . By this, from composite graphite-containing refractory bricks mainly composed of alumina graphite and zirconia graphite, which have not been reused conventionally,
Zirconia graphite, which is a valuable resource, can be economically recovered. In the method for recovering valuable resources from used graphite-containing refractory bricks according to the present invention, it is preferable that the graphite-containing refractory brick is mainly composed of one of magnesia graphite and zirconia graphite. Thus, even for graphite-containing refractory bricks when one of magnesia graphite or zirconia graphite is mainly used, without removing the slag adhered by hand,
It is possible to economically recover valuable resources.

[0006] In the method for recovering valuable resources from used graphite-containing refractory bricks according to the present invention, it is preferable that the crushing treatment is performed through a plurality of steps. Thus, by crushing the graphite-containing refractory brick through a plurality of steps, without crushing the particles to a powder state, it is possible to crush to a composite state of graphite and other substances. . In the method for recovering valuable materials from used graphite-containing refractory bricks according to the present invention, it is preferable that the powder generated by the crushing treatment is treated by flotation to recover the contained valuable materials. By treating the powder generated by the crushing by flotation as described above, it becomes possible to recover the valuable material that has turned into the powder without discarding it.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention. Here, FIG. 1 is a flowchart of a method for recovering valuable materials from used graphite-containing refractory bricks according to an embodiment of the present invention, and FIGS. 2A and 2B are wet-type methods applied to the same method, respectively. Explanatory diagram of the jig ore separator when the piston is lowered, and when the piston is raised, FIG. 3 is a front sectional view of a wet specific gravity separator applicable to the method, FIG.
(A) and (b) are a side sectional view and a front sectional view of a dry specific gravity separator applicable to the method, respectively. FIG. 5 is a front sectional view of a flotation machine applied to the method and FIG. ) And (b) are flowcharts of first and second methods for purifying the recovered valuable material, respectively, and FIG. 7 is a flowchart of a method for recovering the valuable material from the used graphite-containing refractory brick according to the comparative example.

The graphite-containing refractory brick applied to the method for recovering valuable materials from the graphite-containing refractory brick according to the present invention comprises:
For example, a composite brick of alumina graphite and zirconia graphite used for continuous casting, and a brick using zirconia graphite alone without compounding,
Other examples include magnesia graphite brick used for lining the converter. Note that slag and / or metal (for example, iron or stainless steel) is attached to the graphite-containing refractory brick described above.
A method for recovering valuable resources from spent graphite-containing refractory bricks according to one embodiment of the present invention, as a graphite-containing refractory brick, a method for recovering valuable zirconia from a composite brick of alumina graphite and zirconia graphite Will be described with reference to FIG.

First, a graphite-containing refractory brick (hereinafter referred to as a refractory brick) is crushed (primary crushing) by a jaw crusher, which is an example of a crusher, so that particles (for example, a particle size of about 1 to 30 mm) are mainly used. I do. Here, an impeller breaker, a roll crusher, a shearing machine, or the like can be used as the crusher. Next, the magnetically attached matter (for example, iron, stainless steel, etc.) contained in the crushed refractory brick is subjected to magnetic separation by a magnetic separation machine,
Remove from crushed refractory bricks. Then, the refractory brick (non-magnetically adhered) subjected to the magnetic separation process is again subjected to a crushing process (secondary crushing) by a jaw crusher so that the particles (for example, the particle size is about 1 to 10 mm) are mainly used. Therefore, also in this case, it is possible to use the other crushers described above.
In this way, by performing the crushing treatment such that the grains are mainly composed, it is possible to crush each as a composite of zirconia and graphite (zirconia graphite) and a composite of alumina and graphite (alumina graphite). It is possible to make the particle size easy.
Here, again, the magnetically attached matter contained in the crushed refractory brick is removed from the refractory brick by performing a magnetic separation process using a magnetic separator. This magnetically treated refractory brick (non-magnetic material)
By using a classifying (sieving) device (for example, a circular sieve, a trommel sieve, etc.) to obtain a particle size of 1 to 10 mm.
And particles having a particle size of less than 1 mm.

[0010] Next, the particle size of 1 to 1
A method for treating 0 mm particles will be described. Particle size 1-1
The 0-mm particles are separated into heavy, light and intermediate materials by a mineral jig 10 (see FIG. 2) which is an example of a wet jig ore separator described later. Here, the heavy material is a zirconia graphite (true specific gravity 3.23 to
Lightweight material is alumina graphite (true specific gravity of about 2.18 to 2.48).
And slag (with a true specific gravity of about 2.20 to 2.50), and the intermediate is a composite of zirconia graphite and alumina graphite that could not be crushed apart by a crusher. The intermediates generated here are crushed separately into zirconia graphite and alumina graphite, so that the crushing treatment (2
Next crushing). Further, it is possible to recover alumina graphite by treating the light-weight material mainly composed of alumina graphite and slag generated in the purification step.

Next, a method for recovering zirconia graphite recovered as a heavy material as zirconia in a purification step will be described. First, a zirconia graphite is crushed by a hammer mill, which is an example of a pulverizing device, with a particle size of 0.1 to 1 mm.
Grind to about mm. Note that, here, an attrition machine, a tower mill (both grinders), a ball mill, a fret mill, and the like can be used as the pulverizing device in consideration of a processing amount, equipment cost, and the like. The magnetism contained in the pulverized zirconia graphite is removed by magnetic separation using a high magnetic force magnetic separator.

The zirconia graphite thus magnetically treated is treated by a rotary kiln as an example of an incinerator to remove the graphite in the zirconia graphite. Therefore, an electric heating furnace or the like can be used as the incinerator by considering the processing amount and the equipment cost. As a result, zirconia, which is a valuable resource, can be recovered, so that it can be used as a raw material for paints and release agents. In the case where the magnetically treated zirconia graphite is used again as a raw material for a refractory brick having the same composition, the zirconia graphite may be used without being treated in an incinerator, so that energy costs can be reduced, and the raw material can be reduced. The time until the production can be shortened.

Here, a method of pulverizing zirconia graphite and then subjecting the zirconia graphite to magnetic separation using a high magnetic force magnetic separator has been described. However, in order to further improve the quality of zirconia, it is also possible to pulverize zirconia graphite and then treat it in a flotation ore separator 70 (see FIG. 5), which will be described later, to collect zirconia as a sediment and perform magnetic separation. In addition, it is also possible to collect the non-magnetically attached matter after performing a magnetic separation process on the suspended matter generated at the time of the sorting in the flotation by a high magnetic force magnetic separator.

Subsequently, a particle size of 1 m separated by a classification device
A method for treating particles having a particle size of less than m will be described. The powder generated by the crushing process, that is, the particles having a particle size of less than 1 mm, are made of a mixture of zirconia graphite, alumina graphite, alumina precipitated on the surface of the brick or the surface layer of the brick when the refractory brick is used, and slag. . Here, alumina and slag are removed from the mixture by treating the particles having a particle diameter of less than 1 mm by flotation using a flotation ore 70. The mixture (heavy material) from which the alumina and the slag have been removed is separated into a heavy material mainly composed of zirconia graphite and a light material mainly composed of alumina graphite by subjecting the mixture to specific gravity using a mineral jig 10. The selected zirconia graphite can be recovered as zirconia by using the same method as the above-described zirconia graphite purification step.
Alumina can also be recovered from lightweight materials by the same method as in the zirconia graphite purification step described above.

As shown in FIGS. 2A and 2B, the mineral jig 10 includes a tank 11 for storing a solvent, a diaphragm 12 provided on the upper left of the tank 11 for pulsating the solvent, and a A box-shaped material-to-be-separated portion 13 provided at the upper right portion of the tank 11 into which the separation material is charged, a valve 14 for feeding water or a solution into the tank 11, and a valve 1
Tank 1 for sending water or solution from 4 to tank 11
1 and a pipe 15 attached to the central portion. The details will be described below.

The diaphragm 12 includes a piston 16, an eccentric shaft 18 provided on the piston 16 and connected to the piston 16 via a connecting rod 17, and a central portion of the piston 16 that allows the piston 16 to slide. And a shaft 19 provided on the shaft. The solvent in the tank 11 is pulsated by moving the piston 16 up and down by the eccentric shaft 18 via the connecting rod 17. In addition, since the eccentric shaft 18 and the valve 14 are connected, FIG.
As shown in FIG. 7, the piston 16 moves upward and the valve 14 changes from the closed state to the open state. On the other hand, FIG.
As shown in FIG. 8, the piston 16 moves downward and the valve 14 changes from the open state to the closed state. Accordingly, the piston 16 is moved from the lower part to the upper part of the shaft 19 by the eccentric shaft 18, and the valve 14 is opened and the water flows into the tank 11 (see FIG. 2B), while the piston 16 is moved by the eccentric shaft 18. Moves from the upper part of the shaft 19 to the lower part,
The valve 14 closes (see FIG. 2A). Therefore, since the vertical movement of the piston 16 is always transmitted to the solvent in the tank 11, the pressure of the piston 16 is applied to the material-to-be-separated mounting portion 13. The eccentric shaft 18 is driven by a motor. The material placing portion 13 has a mesh body 20 at the lower portion, and is fixed to the tank 11 via a spring member 21 so that the material placing portion 13 can be moved up and down. With such a configuration, the pulsation generated by the vertical movement of the piston 16 is applied to the material-to-be-separated portion 13, the material-to-be-separated portion 13 moves up and down, and the heavy object is moved from the mesh of the mesh body 19. It will fall to the bottom of the tank 11. Here, the heavy object dropped to the bottom of the tank 11 is taken out from the material outlet 22 or the outlet 23 at the lower end of the tank. On the other hand, the light-weight object remains in the material-to-be-separated portion 13.

[0017] In addition to the wet jig separator, specific gravity separation can be performed by the following specific gravity separator (wet specific gravity separator 30, dry specific gravity separator 50). FIG.
As shown in the figure, the wet-type specific gravity separator 30 includes a specific gravity separation case 31 for separating the crushed material, and a specific gravity separation case 3.
1 and a support table 34 for disposing the specific gravity separation case 31 on a base 33 disposed on the floor. The details will be described below. Support table 34
Is installed at an angle to the floor (for example, about 5 to 15 degrees) by adjusting the height of one side of the support base 34 by a height adjustment device 35 provided at one end of the base 33. It becomes possible.

The specific gravity separation case 31 has an angle θ with respect to the floor by a pair of elastically supported support members 36 provided at the upstream and downstream positions on the upper surface of the support table 34, respectively.
(E.g., about 5 to 25 degrees)
Vibration is applied by an eccentric crank 37 provided at the center of the support base 34 and substantially driven back and forth in the axial direction.
Above the specific gravity separation case 31, there are provided, for example, a tub-type shower unit 38 for flowing water, which is a separating means, and a nozzle shower unit 39 for flowing water at an equal pressure. The eccentric crank 37 is driven by a motor 40.

As the material supply device 32, a constant-rate supply device capable of supplying a crushed material (material to be separated) to the specific gravity separation case 31 in a fixed amount is used. With such a configuration, the material to be separated is thrown into the specific gravity separation case 31 by a fixed amount from the material supply device 32, and the light material is removed by the vibration from the eccentric crank 37.
1 moves to the downstream side of the specific gravity separation case 31, respectively. At this time, the surface of the specific gravity separation material is wet by the water supplied from the tub type shower machine 38 onto the specific gravity separation case 31, and dust does not float in the atmosphere.
Further, the light-weight material that has moved to the downstream side of the specific gravity separation case 31 is discharged from one end B of the specific gravity separation case 31 by water from the nozzle shower device 39. On the other hand, the heavy object moved to the upstream side of the specific gravity separation case 31 is discharged from the other end A.

As shown in FIGS. 4A and 4B, a dry-type specific gravity separator 50 includes a specific gravity separation case 52 having a net-shaped vibrating body 51 at an upper portion, and a material provided above the specific gravity separation case 52. It has a supply device 53 and a support table 55 for installing the specific gravity separation case 52 on a base 54 arranged on the floor.
The details will be described below.

The specific gravity separation case 52 is inclined on the support table 55 by elastic support members 56 provided in pairs at the upstream and downstream sides of the support table 55, respectively. An eccentric crank (not shown) that reciprocates substantially vertically and vibrates the specific gravity separation case 52 is provided at the center of the support base 55. The inclination of the specific gravity separation case 52 is an inclination angle α (for example, about 1 to 10 degrees) with respect to the floor. Above the specific gravity separation case 52, air blown uniformly from below the specific gravity separation case 52 by a fan device (not shown) is used.
The mesh vibrator 51 is formed so that the material to be separated on the specific gravity separation case 52 can float. Note that the air flow is equalized by a rectifying member (not shown). The material supply device 53 uses a fixed-quantity supply device capable of supplying a crushed material (material to be separated) in a fixed amount onto the net-shaped vibrating body 51 formed in the specific gravity separation case 52.

The material supply device 53, the specific gravity separation case 52, and the material supply port below the material supply device 53 are surrounded by a casing 57,
7 is connected to a cyclone 59 via a pipe 58.
Thus, dust and the like generated during the operation of the dry-type specific gravity separator 50 are transported from the inside of the casing 57 to the cyclone 59 via the pipe 58 without leaking to the outside of the casing 57. Therefore, the air and dust sent into the casing 57 are separated by the cyclone 59, and the dust is collected. With this configuration, when the fan device is started, air is blown from the fan device into the reticulated vibrator 51, the air passes through the mesh of the reticulated vibrator 51, and the material to be separated is blown up together with the air. When the eccentric crank is driven, the specific gravity separation case 52 is in a vibration state.

The material to be separated which has fallen on the net-like vibrator 51 receives a vibration force due to the vibration of the net-like vibrator 51, and a heavy object is discharged from one end D of the net-like vibrator 51. Then, the light-weight object floats by the air blown up from the mesh of the net-like vibrating body 51 and moves to the downstream side of the net-like vibrating body 51 by the air sliding phenomenon without much influence of the vibration of the net-like vibrating body 51. The light-weight object moved to the downstream side is discharged from the other end C of the mesh vibrator 51. In addition, since air is used here,
It is possible to reduce the inclination angle α.

A flotation machine 70 for performing flotation applied to a method for recovering valuable materials from used graphite-containing refractory bricks according to an embodiment of the present invention will be described. FIG.
As shown in (1), a Fahrenwald type (FW type or Denver SubA type) flotation ore separator 70 stirs a tank 71 that stores a solvent, a powder charged in the solvent, and air blown into the solvent. And a stirring unit 72. The details will be described below. The stirring section 72 includes a stirring blade 73 for mixing and stirring the powder and the air, a rotating shaft 75 connected to the stirring blade 73 at a lower portion for transmitting power to the stirring blade 73, and a motor 74 at an upper portion. And a tubular tube 76 surrounding the shaft 75 and sending air in the atmosphere to the stirring blade 73. Further, a pipe 77 capable of feeding powder from outside the tank 71 to the stirring blade 73 is provided below the pipe 76, and a guide 78 for miniaturizing air is provided around the stirring blade 73. . The air in the atmosphere is blown into the pipe 76 by a compressor (not shown) or the like.
With this configuration, the air sent into the stirring blade 73 from the atmosphere causes the stirring blade 7 to rotate due to the rotation of the stirring blade 73.
Since the size is reduced between the guide 3 and the guide 78, the surface area can be increased. The guide 78 allows the tank 71
Since the influence of the rotation of the stirring blade 73 on the solvent in the tank 71 can be suppressed, there is no possibility that the powder that has settled at the bottom of the tank 71 is scattered at the top.

The principle of separating the material to be separated into powder using the flotation ore separator 70 will be described below. By introducing air into the water (called pulp) in which the material to be separated is suspended and agitating, certain solid particles in the material to be separated become bubbles due to the property that the surface is hardly wetted by water. The other types of solid particles in the material to be separated and adhered to each other remain in the water because they are easily wettable by the water. The particles that have adhered to the bubbles rise to the surface of the pulp due to the buoyancy of the bubbles, forming a foam, or floss, and are separated and discharged. In addition, among the particles suspended in water, those with a surface that is not easily wetted by water selectively adhere to bubbles, while those with a surface that is easily wettable by water stay in water as it is. However, the strength of the tendency of the adhesion is determined by a relation of interfacial energy between three phases of solid (powder), liquid (water), and gas (air). This is very generally represented by the concept of a contact angle. In other words, the important conditions for conducting flotation are, in addition to the type, amount, timing and method of addition of each reagent, the particle size of the powder, pulp concentration, temperature, pH, properties of water, and the intensity of stirring. (Degree of bubble introduction)
And so on.

In the above embodiment, a method of recovering valuable zirconia from refractory bricks obtained by combining alumina graphite and zirconia graphite has been described. However, any material can be used as long as the material can be selected from specific gravity. Therefore, bricks using zirconia graphite alone without being compounded, magnesia graphite bricks (true specific gravity of about 2.80 to 2.87), and slag attached to the bricks are used. Can also be sorted by specific gravity. As a result, it is possible to separate the zirconia graphite and the magnesia graphite from the heavy ones mainly composed of valuable zirconia graphite and magnesia graphite and the lightweight ones mainly composed of slag, thereby recovering the zirconia graphite and the magnesia graphite.

In the above-described embodiment, a case has been described in which the jig ore separator and the flotation separator for specific gravity separation are used one by one, and the material to be separated is subjected to the specific gravity separation and the flotation separation. However, in order to improve the quality of valuable resources to be recovered, for example, by installing 2 to 5 units in series, it is also possible to continuously process sequentially, and one tank can be used.
For example, by dividing into two to five sections, it is also possible to process sequentially. Furthermore, when using a jig ore separator arranged in series or a jig ore separator with one tank divided, it is also possible to separate heavy, intermediate and lightweight objects at each part. is there. Thereby, it becomes easy to collect the heavy, the intermediate, and the lightweight, respectively.

In the above-mentioned embodiment, the case where the specific gravity of the material to be separated is carried out by a wet jig ore separator, but the dry jig or the wet and dry specific gravity separators as well as the specific gravity are used. It is also possible to use a spiral beneficiator, which is a kind of beneficiator. The spiral beneficiator utilizes a centrifugal force generated in a solution comprising a material to be separated and a solvent (for example, water) moving in a spiral tube. Therefore, when the solution is swirled, those having a low specific gravity in the material to be separated receive an outward force together with the solvent, while those having a high specific gravity are greatly affected by gravity and gather at the bottom of the tube. Sort out. And in the said embodiment, although the crushing process was performed through the two processes of the primary crushing and the secondary crushing, since it suffices if it can be crushed to a state where specific gravity can be easily separated, the hardness and strength of the material to be crushed, etc. Depending on physical property values, crystal grain size, valuables content, etc., and the required quality of the valuables to be recovered, it is possible to process through one or more steps (for example, about 3 to 5 steps). It is.

[0029]

EXAMPLES The results of tests conducted by applying the method for recovering valuable materials from used graphite-containing refractory bricks according to the present invention will be described. The used graphite-containing refractory brick to be treated here is a continuous casting nozzle used in the steel making process, and its weight is 65.92 kg. This graphite-containing refractory brick (hereinafter, referred to as a refractory brick) was crushed by a jaw crusher, and then subjected to magnetic separation by a magnetic separator to collect valuable materials using a non-magnetized material as a test sample. In addition, the recovery yield of the non-magnetized material was 91% by weight with respect to the refractory brick. Here, the analysis results of the components of the refractory brick are shown in Table 1.

[0030]

[Table 1]

This test sample was divided so that the compositions did not differ, and two test samples A and B were produced. First, using the sample A, a method of recovering valuable materials from the refractory brick was applied and processed. The refractory brick subjected to the magnetic separation treatment was classified into particles mainly having a particle size of 1 to 10 mm (hereinafter, referred to as a particle size) and particles mainly having a particle size of less than 1 mm (hereinafter, referred to as a powder size) by a circular sieve. At this time, the yield of the grain size with respect to the test sample was 83% by weight. Table 2 shows the particle size distribution.

[0032]

[Table 2]

The particles having the particle size after the classification were separated by specific gravity using a wet jig separator to obtain a heavy product. In addition, the yield of the heavy object with respect to the test sample was 21% by weight, and the analysis results of the components are as shown in Table 3.

[0034]

[Table 3]

The following two methods were used to purify the weight. The first method will be described. FIG.
As shown in (a), the weight obtained by specific gravity sorting is pulverized to less than 1 mm with a ball mill, and then subjected to magnetic separation by magnetic separation, and the magnetically processed weight is fired in an oxidizing atmosphere to obtain a weight. The carbon contained in the material was removed. The firing conditions are a temperature of 900 ° C. and a holding time of 10 minutes. Here, the yield of the fired product (non-magnetically attached matter) with respect to the test sample was 14% by weight. Table 4 shows the analysis results of the components.

[0036]

[Table 4]

As a result, the zirconia recovered at a grade of 98% or more was 8% less than the zirconia in the test sample.
It was found to be 2% by weight. Next, the second method will be described. As shown in FIG. 6 (b), as a result of grinding the heavy material with a ball mill, the particle size distribution after the grinding was as shown in Table 5.
Was the result.

[0038]

[Table 5]

Flotation was performed on the pulverized product.
The conditions of the flotation were adjusted to pH 8.5 to 9, and 2.8 g of kerosene as a collector per 1000 g of flotation raw material,
0.2 g of pine oil # 5 was added as a foaming agent. As a result, the recovery of sediment was 34% by weight of the flotation raw material.
Met. The suspended matter and the sediment were collected, dehydrated, and dried. The dried suspended matter and the sediment were subjected to a magnetic separation treatment with a high magnetic separation machine having a magnetic flux density of 2.8 T (tesla), and non-magnetically attached matter was recovered. Tables 6 and 7 show the analysis results of the non-magnetically attached matter recovered from the suspended matter and the sediment, respectively.
It is.

[0040]

[Table 6]

[0041]

[Table 7]

As a result, the zirconia recovered with a grade of 97% or more was 4% less than the zirconia in the test sample.
It was found to be 1% by weight. Next, a comparative example will be described. Using the sample B, the processing was performed according to the flow shown in FIG. First, the refractory brick subjected to the magnetic separation was pulverized by a fret mill, and after pulverization, classified into a large size and a small size by an air classifier. At this time, the yield of the large-sized side with respect to the test sample was 69% by weight. In addition,
Table 8 shows the particle size distribution.

[0043]

[Table 8]

After the classification, the large-sized side was subjected to specific gravity sorting by a wet specific gravity separator to obtain a heavy material, and the heavy material was subjected to magnetic separation by magnetic separation to recover non-magnetic particles, that is, zirconia. The yield of the heavy object relative to the test sample is 2.
At 4% by weight, the results of analysis of the components are as shown in Table 9.

[0045]

[Table 9]

As a result, the zirconia recovered at a grade of 97% or more was 1% less than the zirconia in the test sample.
It was found to be 3% by weight. From the above, the recovery rate of zirconia when recovering zirconia from the test sample was 82% by weight in the first method of the present invention and 13% by weight in the comparative example. By this, when performing specific gravity separation, it is found that it is more advantageous to stop crushing at a size that is easy to separate and then separate and remove graphite, rather than performing elemental separation, that is, separation of zirconia and graphite, and then separating. Was. In the second method of the application example of the present invention, the recovery rate of zirconia when recovering zirconia from the test sample was 41% by weight. Although this is lower than the zirconia recovery rate of 82% by weight when zirconia is purified by the first method,
It was found that the zirconia recovery of the comparative example was higher than 13% by weight.

[0047]

According to the method for recovering valuable materials from used graphite-containing refractory bricks according to the first to fifth aspects, the graphite-containing refractory brick is crushed so that grains are mainly used, so that specific gravity ore separation becomes easy. In addition, it is possible to recover heavy materials mainly composed of valuable materials at a high recovery rate at the time of specific gravity separation. In addition, graphite-containing refractory bricks to which slag and / or metal adhered have conventionally been manually removed for slag or discarded, but without manually removing slag or the like, and without discarding. In addition, it is possible to collect and reuse heavy materials mainly composed of valuable materials from graphite-containing refractory bricks. This makes it possible to reduce the amount of valuable resources used in refractory resources by adding the collected valuable resources to the blend of refractory bricks of the same material or by adding and reusing them as refractory aggregates. Therefore, raw material costs can be reduced. Further, since the collected valuable resources can be used for paints and mold release agents, raw material costs can be reduced. Further, since it is not necessary to manually collect valuable resources, work efficiency is improved and workability is improved.

In particular, in the method for recovering valuable materials from used graphite-containing refractory bricks according to the present invention, a composite graphite-containing refractory brick mainly composed of alumina graphite and zirconia graphite, which has not been reused, is used. In addition, zirconia graphite, which is a valuable resource, can be economically recovered. As a result, zirconia graphite, which is a valuable resource, can be collected and reused, so that it is possible to further reduce the amount of valuable material used for refractory resources. In the method for recovering valuable resources from used graphite-containing refractory bricks according to claim 3,
Regarding graphite-containing refractory bricks mainly composed of magnesia graphite or zirconia graphite, valuable resources can be economically recovered without manually removing slag and the like attached thereto. Thereby, work efficiency is improved and workability is also improved.

In the method for recovering valuable resources from used graphite-containing refractory bricks according to claim 4, the graphite-containing refractory bricks are crushed through a plurality of steps so that the particles are not pulverized to a powder state. Thus, it is possible to crush to a state of a composite of graphite and another substance. As described above, by collecting valuable resources as a composite of graphite and other substances, specific gravity separation becomes easier, so that heavy substances mainly composed of valuable substances can be recovered at a higher recovery rate during specific gravity separation. It becomes possible. In the method for recovering valuable resources from used graphite-containing refractory bricks according to claim 5, the powder generated by crushing is treated by flotation to recover the valuable resources that have become powder without discarding. It is possible to improve the recovery rate of valuable resources.

[Brief description of the drawings]

FIG. 1 is a flowchart of a method for recovering valuable resources from used graphite-containing refractory bricks according to an embodiment of the present invention.

FIGS. 2 (a) and 2 (b) are an explanatory view when the piston is lowered and an explanatory view when the piston is raised in a wet jig concentrator applied to the same method.

FIG. 3 is a front sectional view of a wet specific gravity separator applicable to the method.

4 (a) and 4 (b) are a side sectional view and a front sectional view of a dry-type specific gravity separator applicable to the same method, respectively.

FIG. 5 is a front sectional view of a flotation machine applied to the method.

FIGS. 6 (a) and (b) are flowcharts of first and second methods for purifying recovered valuable resources, respectively.

FIG. 7 is a flowchart of a method for recovering valuable resources from used graphite-containing refractory bricks according to a comparative example.

[Explanation of symbols]

10: Mineral jig, 11: Tank, 12: Diaphragm, 13: Placement of material to be separated, 14: Valve, 15:
Pipe, 16: piston, 17: connecting rod, 18: eccentric shaft, 1
9: shaft, 20: net, 21: spring member, 22: material outlet, 23: outlet, 30: wet specific gravity separator, 31:
Specific gravity separation case, 32: material supply device, 33: base, 3
4: support base, 35: height adjustment device, 36: support member, 3
7: eccentric crank, 38: tub type shower machine, 39: nozzle shower machine, 40: motor, 50: dry specific gravity sorter, 51: mesh vibrator, 52: specific gravity separation case, 53:
Material supply device, 54: base, 55: support, 56: support member, 57: casing, 58: pipe, 59: cyclone, 70: flotation separator, 71: tank, 72: stirring section,
73: stirring blade, 74: motor, 75: rotating shaft, 76:
Tube, 77: Tube, 78: Guide

Continued on front page F-term (reference) 4D004 AA16 AC05 BA02 BA06 CA04 CA08 CA09 CA10 CA28 CB05 CB09 CB13 4D067 DD02 DD10 DD15 GA08 GB05 4D071 AA12 AA17 AA54 AB13 AB14 AB23 CA01 CA03 CA05 DA15 DA20 4K001 AA10 CA24 DB24

Claims (5)

[Claims] 1. A graphite-containing refractory brick to which slag and / or metal has adhered by use is subjected to a crushing treatment so that grains are mainly contained, and a magnetically adhered substance contained in the crushed graphite-containing refractory brick is subjected to a magnetic separation treatment. After removal from the graphite-containing refractory bricks, the graphite-containing refractory bricks subjected to the magnetic separation are separated into a heavy material mainly composed of valuable materials and a light material mainly composed of slag by specific gravity sorting. A method of recovering valuable materials from refractory bricks. 2. The method for recovering valuable materials from used graphite-containing refractory bricks according to claim 1, wherein the graphite-containing refractory bricks are mainly composed of alumina graphite and zirconia graphite, and the heavy material is composed of zirconia graphite. A method for recovering valuable resources from used graphite-containing refractory bricks, characterized by the following. 3. The method for recovering valuable materials from used graphite-containing refractory bricks according to claim 1, wherein said graphite-containing refractory bricks are valuable from used graphite-containing refractory bricks mainly composed of magnesia graphite or zirconia graphite. How to collect things. 4. The method for recovering valuable resources from used graphite-containing refractory bricks according to claim 1, wherein the crushing treatment is performed through a plurality of steps. Of recovering valuable materials from used graphite-containing refractory bricks. 5. The method for recovering valuable materials from used graphite-containing refractory bricks according to claim 1, wherein the powder generated in the crushing treatment is processed by flotation and included. A method for recovering valuable resources from used graphite-containing refractory bricks, comprising recovering valuable resources.