KR101316940B1 - Valuables Recovering Method from Waste Carbon Brush - Google Patents

Abstract

The present invention relates to a method for recovering valuable resources from the waste carbon brush, the recovery method according to the invention comprises the steps of crushing the waste carbon brush; Separating the Cu lead wire from the crushed waste carbon brush using sieving; And separating and recovering carbon and copper from the waste carbon brush from which the Cu lead wire is separated using floating screening.

Description

Valuables Recovering Method from Waste Carbon Brush

The present invention relates to a method for recovering valuable resources from waste carbon brushes, and more particularly, to a recovery method for recovering copper wire, copper powder, and carbon powder from waste carbon brushes in high purity.

The basic functions of the carbon brush are energization and sliding (sliding movement), and the constituent materials are Cu powder to secure electrical conductivity, natural graphite to secure lubricity and wear resistance, and a binder (mainly phenol) to combine them. It is.

Most of the carbon brushes are made of carbonaceous, graphite, electrographite and metallic graphite materials. In general, the brush is attached with a pigtail made by twisting a thin interlocking wire for supplying power.

Carbon brush is an important component that plays a role of energizing and rectifying by contacting the surface of the commutator of various rotating machines such as cross-flow machines for electric machines or the rotating part of the slip ring, as in Korean Patent Publication No. 2009-0090238, as a material of ceramic system. It has rich lubricity and high conductivity, heat resistance, arc resistance and low friction characteristics. It also plays an important role in reversibly transferring electricity between the rotor and the stationary body.

In order to maintain a constant contact state, the carbon brush is required to follow, low friction, atmosphere of the place of use, and these characteristics vary depending on the number of revolutions, load, atmosphere, use, etc. Brushes are developed and sold.

Such carbon brushes are recovered in small amounts for the purpose of recovering copper wire only when lead wires are attached, and about 300 tons or more of waste carbon brushes are discarded annually in Korea.

  Carbon brushes are not recyclable because they have different properties for different types of brushes and brushes. In addition, reliability is important because the environment used is used in a harsh atmosphere. Therefore, the importance of recycling carbon brushes, which are disposed of entirely, has emerged as an important issue.

Republic of Korea Patent Publication No. 2009-0090238

It is an object of the present invention to provide a method for recovering valuable resources from waste carbon brushes that can reduce the cost of manufacturing and recycle high value-added materials by minimizing and recycling the amount of carbon brushes that are discarded.

Specifically, it is an object of the present invention to provide a method for recovering valuable resources including particulate carbon, copper wire and particulate copper from waste carbon brushes, and having a purity of 96% (by weight percent). The present invention provides a method for recovering copper having a purity of 97% (quality based on weight percent) and a copper lead wire having a purity of 98% (quality based on weight percent), respectively.

Recovery method of valuable resources from the waste carbon brush according to the present invention comprises the steps of crushing the waste carbon brush; Separating the Cu lead wire from the crushed waste carbon brush using sieving; And separating and recovering carbon and copper from the waste carbon brush from which the Cu lead wire is separated using floating screening.

A recovery method according to an embodiment of the present invention includes a) a crushing step of crushing the waste carbon brush using a crusher (crusher); b1) a lead wire separating step of separating and recovering the Cu lead wire from the waste carbon brush crushed using a sieve having a size of 1 mm to 10 mm; b2) a lead wire crushing step of separating the Cu lead wires and the impurities including carbon bonded to the Cu lead wires separated and recovered by using a grinder; b3) a lead wire re-separation step of sieving the product obtained by the lead wire crushing step with a sieve of 15 to 30 mesh to separate and recover the lead wires; c1) a carbon brush single separation step of separating the carbon and copper contained in the waste carbon brush from which the Cu lead wire is separated and removed in the lead wire separation step using a grinder; And c2) separating and recovering carbon and copper by flotation of the pulverized waste carbon brush obtained in the carbon brush single separation step.

In the recovery method according to an embodiment of the present invention, step c2) is sifted through a sieve of 150 to 250 mesh (sieve) of the pulverized waste carbon brush obtained in the c3) carbon brush single separation step, passing through the sieve Separating and separating the first and second products that have not passed through the sieve; And c4) separating and recovering carbon and copper by flotation for each of the first product and the second product.

In the recovery method according to an embodiment of the present invention, the second product is a sedimentation step before sedimentation, after mixing and stirring the second product and water is performed, and the sedimentation product for the sedimentation product of the sedimentation step This can be done.

In the recovery method according to an embodiment of the present invention, before the flotation of the first product, the step of separating the carbon and copper contained in the first product by a grinder may be further performed.

In the recovery method according to an embodiment of the present invention, during the flotation, 15 to 20 cc of sodium silicate (Na ₂ SiO ₃ ) as a dispersant per ton of mineral liquid (pine oil) 50 to foaming agent 150 g and 80 to 120 g of kerosene (Kerosene) can be added as a collecting agent.

In the recovery method according to an embodiment of the present invention, the flotation for the sedimentation product of the sedimentation step includes a barge and a line, and the line can be performed three to four times.

In the recovery method according to an embodiment of the present invention, the grinding of the lead wire grinding step and the carbon brush single separation step may be performed using a load mill, respectively.

The recovery method according to the present invention has the advantage of recovering valuable resources including carbon, copper, and copper wire from the waste carbon brush, which is almost entirely disposed of, and uses carbon with a purity of 96% (degrees by weight). The copper powder can be recovered, and the copper powder can be recovered at a purity of 97% (weight percent based on weight) or higher, and the copper lead wire can be recovered at a purity of 98% (weight percent based on weight).

1 is a view showing a process diagram of a recovery method according to an embodiment of the present invention,
2 is a view showing a process diagram of a recovery method according to another embodiment of the present invention,
3 is a view showing a process of the recovery method according to another embodiment of the present invention,
4 is a view showing a process of the recovery method according to another embodiment of the present invention,
5 is a stereomicrograph of a raw material used in the preparation example,
6 is a view showing the results of X-ray diffraction analysis of the raw material used in the preparation example,
FIG. 7 is a diagram showing the results of energy dispersive spectroscopy (SEM-EDS) attached to a scanning electron microscope of a raw material used in the preparation example.

Hereinafter, the recovery method of the present invention will be described in detail with reference to the accompanying drawings. The drawings introduced below are provided by way of example so that the spirit of the invention to those skilled in the art can fully convey. Therefore, the present invention is not limited to the following drawings, but may be embodied in other forms, and the following drawings may be exaggerated in order to clarify the spirit of the present invention. Hereinafter, the technical and scientific terms used herein will be understood by those skilled in the art without departing from the scope of the present invention. Descriptions of known functions and configurations that may be unnecessarily blurred are omitted.

1 is an example showing a process diagram of a recovery method according to an embodiment of the present invention. As shown in Figure 1, the recovery method according to an embodiment of the present invention is a method of recovering valuable resources from the waste carbon brush is a step of crushing the waste carbon brush (s100); Separating the Cu lead wire from the crushed waste carbon brush using sieving (s200); And separating and recovering carbon and copper from the waste carbon brush from which the Cu lead wire is separated using floating screening (s300).

In the present invention, the carbon brush includes metal graphite, metal impregnated graphite, artificial graphite, carbonaceous, carbon graphite or resin binder carbon brush. In addition, in this invention, carbon means the carbon component contained in the waste carbon brush.

As shown in FIG. 1, in the recovery method according to an embodiment of the present invention, the waste carbon brush is crushed and sieved to separate and recover the Cu lead wire from the waste carbon brush. That is, the crushed waste carbon brush is sieved to separate and recover the Cu lead wire which cannot pass through the sieve and the product that passes through the sieve (hereinafter, the lead wire removal product).

Thereafter, the lead wire removal product is sorted by floating to separate and recover carbon (particulate) and copper (particulate) contained in the waste carbon brush.

2 is another example showing a process diagram of a recovery method according to another embodiment of the present invention. As shown in Figure 2, the recovery method according to an embodiment of the present invention a) shredding the waste carbon brush using a crusher (crusher) (s110); b1) a lead wire separation step of separating and recovering the Cu lead wire from the waste carbon brush crushed using a sieve having a size of 1 mm to 10 mm (s210); b2) a lead wire crushing step (s220) for separating the Cu lead wire and the impurities including carbon bonded to the Cu lead wire separated and recovered by using a grinder (s220); b3) a lead wire re-separation step (s230) of sifting the product obtained by the lead wire crushing step with a sieve of 15 to 30 mesh to separate and recover the lead wire; c1) a carbon brush single separation step (s310) for separating the carbon and copper contained in the waste carbon brush from which the Cu lead wire is separated and removed in the lead wire separation step using a grinder; And c2) separating and recovering carbon and copper by flotation of the pulverized waste carbon brush obtained in the carbon brush single separation step (s320).

Mechanisms for grinding or crushing solids can be classified into four principles: compression, impact, abrasion and cutting. It is known that the grinding mechanism not only affects the grinding efficiency, but also affects the characteristics of the grinding products such as particle size distribution and fine powder generation.

The crushing step (s110) for separating and recovering the lead wire from the waste carbon brush is preferably performed by using a crusher, and in particular, by using a jaw crusher or a roll crusher (compressor crusher) It is more preferable to crush the waste carbon brushes by the compression force and the shear force (roll crusher).

After crushing the waste carbon brush as a raw material, a lead wire separation step (s210) of sifting the crushed waste carbon brush using a sieve having a size of 1 mm to 10 mm is performed.

The lead wire separating step (s210) prevents the generation of fine powder by the compressive force (and the shear force), and sifts the crushed waste carbon brushes into sieves having a mesh size of 1 mm to 10 mm, thereby preventing lead wires and sieves from passing through the sieve. It is a step of separating and recovering the product (lead wire removal product) passing through.

In the lead wire separated and recovered by the lead wire separating step s210, impurities attached (coupled) to the lead wire are present, and post-treatment is preferably performed to recover lead wire having a high purity of 90% or more.

Accordingly, crushing using a grinder is performed on the lead wires separated and recovered in the lead wire separating step s210 to perform a lead wire crushing step s220 for separating the lead and the lead wires separately.

It is particularly preferable that the single separation of the lead wire and the impurities attached to the lead wire is performed using a rod mill in which grinding is performed by shearing force. As a result, the single separation between the lead wire and the impurity can be effectively achieved, and the fineness of the impurity separated from the lead wire can be prevented.

After the lead wire crushing step (s220) is made, the product obtained by the lead wire crushing step (s220) is sieved with a sieve of 15 to 30 mesh to prevent the product from passing through the sieve as a lead wire, and the product passes through the sieve. The lead wire re-separation step (s230) of re-isolating and recovering the lead wire as a residual product is performed.

In the recovery method of the present invention, through the above-described lead wire separating step (s210), lead wire crushing step (s220) and lead wire re-separating step (s230), it is possible to recover the copper lead wire having a purity of 98% or more.

As shown in FIG. 2, the flotation screen is performed on the lead wire removal product obtained in the lead wire separation step (S210). Before the flotation screen is performed, the waste carbon brush is removed using a grinder on the lead wire removal product. A carbon brush simple separation step (s310) for separating carbon and copper contained in the (lead wire removal product) into pieces is performed.

In the carbon brush single separation step (s310), the single separation between carbon and copper is particularly preferably performed using a rod mill in which grinding is performed by shearing force. As a result, it is possible to effectively achieve a single separation between carbon and copper, and to prevent micronization that lowers the efficiency of flotation and the purity of the obtained product.

At this time, the carbon brush single separation step (s310) is a load mill is performed on the mixed product including both the lead wire removal product obtained in the lead wire separation step (s210) and the lead wire residual product obtained in the lead wire re-separation step (s230) It is preferable.

This can increase the recovery of carbon and copper from the waste carbon brush, it is possible to minimize the amount of waste discarded.

When performing the rod mill of the carbon brush single separation step (s310), the amount of rod may be 30 to 50% by volume of the volume of the mill, and the mass ratio of the water to the material to be milled may be 1: 0.8 to 1.2. The number can be 50 to 100 rpm and the milling can be performed for 15 to 30 minutes.

After the carbon brush simple separation step (s310) is performed, a flotation screening step (s320) for selectively recovering particulate carbon and particulate copper using a flotation screening is performed.

Float screening is a physicochemical screening method that uses the surface characteristics of solid particles to be separated. In other words, when a bubble is generated by blowing air into a suspended liquid solution (pulp), the hydrophobic material adheres to the bubble and floats on the water surface, while the hydrophilic material remains in the mineral solution.

An activator may be added to form a mineralized froth so that the mineral particles float to the surface. Meanwhile, a depressant is used to settle the floating ore, a foam is used to improve the stability of the bubbles, and an acid and alkali type pH regulator is used to control the pH of the mineral solution. . Flotation screening is a method of separating the target minerals by adding these reagents at a suitable time and process, and the screening efficiency may vary greatly depending on the type of reagent, the type of mineral, and the particle size distribution of the mineral.

In the flotation screening step (s320), in order to recover carbon concentrates with high purity and high efficiency by selective flotation of carbon, 15 to 20 cc of sodium silicate (Na ₂ SiO ₃ ) as a dispersant per ton of mineral liquid, a fine oil as a foaming agent Preference is given to adding 50 to 150 g of pine oil and 80 to 120 g of kerosene as a collecting agent. As a result of flotation with varying amounts of dispersant, foaming agent and trapping agent, if it is out of the above range, the purity of carbon recovered from concentrate and / or the purity of copper recovered from tail is low. It was confirmed that the loss, or the recovery rate is reduced.

3 is another example showing a process diagram of a recovery method according to another embodiment of the present invention.

As shown in FIG. 3, it is preferable that the particle size separation step s315 is performed before the floating screening is performed on the product obtained by the carbon brush single separation step s310.

When waste carbon brush used as raw material is crushed using jaw crusher or roll crusher to remove lead wire, and then crushed using rod mill for single separation, copper It is divided into a product containing a large amount and a product containing a large amount of carbon.

Accordingly, in order to improve the efficiency at the time of flotation and to improve the purity of the valuable resources to be recovered, the pulverized waste carbon brush obtained in the carbon brush simple separation step (s310) is sieved through a sieve of 150 to 250 mesh. Thus, the particle size separation step (s315) of separating and selecting the first product that did not pass through the sieve and the second product that passed through the sieve is preferably performed.

Through the particle size separation step (s315), the first product containing at least 89% by weight of carbon and the second product containing at least 65% by weight of copper may be separated and recovered.

For each of the first product and the second product separated and recovered through the particle size separation step s315, floating screens s321 and s322 are performed independently of each other. In this case, 1 ton of mineral liquid in each screening screen s321 and s322 is performed. 15 to 20 cc of sodium sodium silicate (Na ₂ SiO ₃ ) as a dispersant per ton), 50 to 150 g of pine oil as a foaming agent and 80 to 120 g of kerosene as a collecting agent are preferably added.

Floating screen (s320, s321, s322) includes a fixed line and a bar (cleaning bar), the bar can be performed once to four times.

Figure 4 is another example showing a process diagram of a recovery method according to another embodiment of the present invention.

The second product is composed of finer particles than the first product, and contains a large amount of copper. Accordingly, there is a risk that the efficiency of floating screening is reduced and the purity of valuable resources recovered is reduced. In order to prevent this, before the flotation screening of the second product (s322) is performed, the second product and water are mixed and stirred, and then settled (free settling by gravity) to remove the water on the top of the settling layer. It is preferable that the settling step s400 of recovering the settled sediments is performed, and the floating screening s322 is preferably performed on the recovered sediments.

That is, when separating and recovering copper and carbon only by flotation without performing the sedimentation step (s400), while recovering only copper having a grade of less than 96%, the sedimentation step (s400) is performed and the sediment is subjected to the target. As a flotation screen (s322), preferably shipbuilding and the flotation screen (s322) consisting of three to four times the fine selection, it is possible to recover the copper having a grade of 98% or more.

That is, even if each of the first product and the second product is subjected to flotation, when the flotation is performed without performing the sedimentation step (s400) for the second product in which a large amount of fine particles are present, a scavenging process is performed. Even if performed very many times more than six times, the quality of the copper is only a slight increase in quality compared to once, the recovery rate is significantly reduced as the selection is repeated.

However, by performing the sedimentation step (s400), when the flotation is performed on the sedimented sediment, the tail product Cu may be recovered at a recovery rate of 25.5% by weight or more and 97% by weight or more.

The first product is composed of particles coarser than the second product, and the first product includes particles in which carbon and copper are bonded to each other. Accordingly, after the first product single separation step (s500) for separating the carbon and copper contained in the first product by using a grinder before the flotation (s321) of the first product is performed, the first product is performed. Floating screening (s321) is preferably performed on the product obtained in the product single separation step (s500). At this time, the floating screening (s321) may be performed including shipbuilding and the selection, the number of selection may be performed once to four times.

The first product single separation step (s500) is particularly preferably performed using a rod mill in which the single separation between carbon and copper is carried out by the shearing force. As a result, it is possible to effectively achieve a single separation between carbon and copper, and to prevent micronization that lowers the efficiency of flotation and the purity of the obtained product.

Hereinafter, the present invention will be described based on the actual production examples, which are provided only to help a more general understanding of the present invention, and the present invention is not limited to the following actual recovery examples. Those skilled in the art can make various modifications and variations from this description.

(Production example)

 AVO Korea waste carbon brushes were collected and used as raw materials. FIG. 5 is a stereomicrograph of a raw material, FIG. 6 is a diagram showing an X-ray diffraction analysis result of the raw material, and FIG. 7 is a diagram showing an energy dispersive spectroscopic analysis (SEM-EDS) result attached to a scanning electron microscope. .

5 to 7, the main constituents of the raw material was carbon and copper, it can be seen that the additives for manufacturing the carbon brush (molybdenite, MoS ₂ ) is included. As a result of SEM-EDS analysis, it was found that the raw material was composed of 47.25 wt% of C, 0.67 wt% of Cu, 0.52 wt% of Mo, and 0.35 wt% of S.

Number of leads

After crushing the raw material with a roll crusher and sieving it to 0.5mm, the + 0.5mm product (product that failed to pass the 0.5mm sieve) is the lead wire, and the -0.5mm product (product that passed the 0.5mm sieve) is waste Separated with carbon brush powder.

200 g of Cu lead wire (+0.5 mm product) and 300 ml of water were mixed to separate the carbon and Cu lead wires attached to the lead wire (+0.5 mm product) and milled at 90 rpm for 8 minutes with a rod mill. . After milling, wet sifting to 18 mesh and the + 18mesh product (the product that did not pass the 18mesh sieve) was finally recovered by Cu lead wire. The recovery rate of the finally recovered Cu lead was 97.12% by weight, and Cu quality of the Cu lead was 98.8% as a result of inductively coupled plasma (ICP) analysis. At this time, the -18mesh product (product passing through the sieve of 18mesh) was mixed with the -0.5mm product.

Separation Recovery of Carbon Powder and Copper Powder

In order to separate and recover carbon and copper by using flotation, a -0.5 mm product was ground using a rod mill. 300g of -0.5mm product and 300ml of water were mixed, and the size of wheat was 190 mm 350 mm in inner diameter and 15 mm 320 mm in rod size. The rotation speed was 70 rpm, the load was 40% by volume of the mill volume, and the grinding time was 20 minutes.

After performing a load mill, wet sieve was performed using a 200 mesh sieve. Analysis of +200 products (products that did not pass through 200 mesh sieves) and -200 products (products that passed through 200 mesh sieves) separated by sieving resulted in +200 products containing 89.66% by weight of C, 4.98 wt% Cu, 1.1 wt% Mo, 0.81 wt% S, 3.39 wt% O were found, and in the -200 product, 15.95 wt% C, 67.01 wt% Cu, 0.55 wt% Mo, S 0.01 Wt%, O 16.38 wt% was present.

Float screening was performed for each of the +200 and -200 products.

Before flotation, put into a cylindrical decanation vessel with a sedimentation diameter of 20 cm and a height of 60 cm for -200 products, stir 15 liters of water, settle for 10 minutes, settle the overflow product, and settle Only the products were subjected to flotation experiments.

For the flotation, a laboratory flocculator (Denver sub-A type floataor, Denver Co., USA) was used.In flotation, ₁₅ cc of Na ₂ SiO ₃ per 100 tons of mineral liquid, 100 g of kerosene, and fine oil 72 g was added. As a result of performing barges and three selections, the recovery rate of the tail (Cu) product was 25.74 wt%, and the Cu quality was 97.4 wt%.

Before flotation, milling was performed using a rod mill on the +200 product. The load mill was mixed with 200 g of +200 product and 200 ml of water and run for 20 minutes at 90 rpm.

For the flotation, a laboratory flocculator (Denver sub-A type floataor, Denver Co., USA) was used.In flotation, ₁₅ cc of Na ₂ SiO ₃ per 100 tons of mineral liquid, 100 g of kerosene, and fine oil 72 g was added. As a result of the barge and one time of selection, the recovery of Conc. Product was 90.48% by weight. At this time, the C grade was 92.8% by weight. At this time, the C grade was 96.7% by weight.

  While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Those skilled in the art will recognize that many modifications and variations are possible in light of the above teachings.

Accordingly, the spirit of the present invention should not be construed as being limited to the embodiments described, and all of the equivalents or equivalents of the claims, as well as the following claims, belong to the scope of the present invention .

Claims (8)

delete a) a crushing step of crushing the waste carbon brush using a crusher;
b1) a lead wire separating step of separating and recovering the Cu lead wire from the waste carbon brush crushed using a sieve having a size of 1 mm to 10 mm;
b2) a lead wire crushing step of separating the Cu lead wires and the impurities including carbon bonded to the Cu lead wires separated and recovered by using a grinder;
b3) a lead wire re-separation step of sieving the product obtained by the lead wire crushing step with a sieve of 15 to 30 mesh to separate and recover the lead wires;
c1) a carbon brush single separation step of separating the carbon and copper contained in the waste carbon brush from which the Cu lead wire is separated and removed in the lead wire separation step using a grinder; And
c2) separating and recovering carbon and copper by flotation of the pulverized waste carbon brush obtained in the carbon brush simple separation step;
Recovery method of valuable resources from the waste carbon brush comprising a. The method of claim 2,
c2) steps
c3) sifting the pulverized waste carbon brush obtained in the carbon brush simple separation step into 150-250 mesh sieve to separate and separate the first product that did not pass through the sieve and the second product that passed through the sieve. step; And
c4) separating and recovering carbon and copper by flotation of each of the first and second products;
Recovery method of valuable resources from the waste carbon brush comprising a. The method of claim 3, wherein
The second product is a sedimentation step of precipitating, after mixing and stirring the second product and water is settled, the sedimentation step of the sedimentation product of the sedimentation step of the sedimentation product is a recovery method of valuable resources from the waste carbon brush. The method of claim 3, wherein
Before the flotation of the first product, the step of separating the carbon and copper contained in the first product by using a grinder (grinder) is further performed to recover valuable resources from the waste carbon brush. The method of claim 2,
In the flotation, 15 to 20 cc of sodium sodium silicate (Na ₂ SiO ₃ ) as a dispersant per ton of mineral liquid, 50 to 150 g of pine oil as a foaming agent and 80 to 120 g of kerosene as a collecting agent A method for recovering valuable resources from added carbon brushes. 5. The method of claim 4,
Floating screening for the sedimentation product includes a barge and a line, wherein the line is recovered from the carbon brush is carried out three to four times. The method of claim 2,
The grinding of the lead wire crushing step and the carbon brush single separation step is a method of recovering valuable resources from the carbon brush is carried out using a load mill, respectively.

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