KR20240021048A - Apparatus for recovering valuable metals from used battery pack and method for the same - Google Patents

Abstract

In order to further increase the efficiency of recovering valuable metals, a flotation step of preparing pretreated powdered raw materials from waste batteries, flotation and removal of graphite at least once from a solution mixed with the prepared raw materials, and leaching of valuable metals. A method for recovering valuable metals from waste batteries is provided, including a leaching step and a filtering step for recovering valuable metals by filtering them.

Description

Waste battery valuable metal recovery method and recovery equipment {APPARATUS FOR RECOVERING VALUABLE METALS FROM USED BATTERY PACK AND METHOD FOR THE SAME}

The present disclosure relates to methods and equipment for recovering valuable metals from waste batteries.

Generally, batteries that can be charged and discharged are used in mobile products such as mobile phones and electric vehicles. As battery usage increases, discarded batteries are emerging as a social problem.

During the battery disposal process, various hazardous substances are emitted and valuable metals are lost. Accordingly, technologies are being researched to more effectively recover and recycle these valuable metals from waste batteries.

In order to recover valuable metals from batteries that have reached the end of their life, the waste batteries are shredded, fired and dissolved, and then the valuable metals are recovered.

However, the conventional structure has a problem in that the recovery rate of valuable metals is reduced due to graphite, an impurity contained in the battery.

For example, in the case of lithium-ion batteries, in addition to the positive electrode active material composed of metal oxide, it contains a large amount of graphite as the positive and negative electrode materials. In order to increase the recovery rate of valuable metals, the graphite contained in the valuable metals must be separated and removed.

However, in the conventional case, it is not easy to separate and remove graphite, which reduces the recovery rate of valuable metals, and graphite is not collected and discharged, which causes environmental pollution and wastes valuable resources to be recycled.

Therefore, improving the conventional valuable metal recovery technology to effectively and environmentally friendly recovery of valuable metals from waste batteries can provide many advantages to users.

This project is to provide a method and recovery facility for valuable metals from waste batteries that can increase the efficiency of valuable metal recovery.

This project is to provide a method and recovery facility for valuable metals from waste batteries that can additionally recover graphite contained in waste batteries.

This project is to provide a method and recovery facility for valuable metals from waste batteries that can reduce the load in post-processing and shorten processing time by recovering valuable metals after removing graphite.

The method for recovering valuable metals of this embodiment includes the steps of preparing raw materials in the form of pretreated powder from waste batteries, a flotation step of floating and screening graphite at least once to remove graphite from a solution mixed with the prepared raw materials, and removing valuable metals leached into the solution. It may include a filtering step of filtering and recovering.

The valuable metal recovery method may further include the step of recovering graphite suspended and sorted through a flotation step.

The preparation step may include a pulverizing step of pulverizing the waste battery and processing it into particles, and a sintering step of baking the pulverized particles and processing them into powder form.

In the flotation step, the particle size of the raw materials mixed into the solution may be greater than 0 and less than or equal to 0.25 mm.

In the firing step, the firing temperature may be 650 to 700°C.

The flotation step includes a first flotation step in which graphite is removed by first flotation from a solution mixed with raw materials, and a second flotation step in which the solution that has passed through the first flotation step is again flotation and sorted to remove graphite. can do.

In the flotation step, the content of valuable metals and graphite in the solution may be 5 to 35%.

In the flotation step, the pH of the solution may be 7 to 10.

In the flotation step, the solution may be NaOH, Na2CO3, or H2SO4 aqueous solution.

The flotation step may include a step of introducing a foaming agent to suspend graphite.

The foaming agent may be at least one selected from MIBC (methyl isobutyl carbinol), pine oil, cresolic acid, alcohol, and kerosene.

In the flotation step, a step of adding a catcher to adsorb graphite to the bubbles may be included.

The catcher may be at least one selected from xantate and aerofloat.

In the flotation step, a step of adding a floating inhibitor to prevent floating of valuable metals may be further included.

The floating inhibitor may be at least one selected from starch, water, and glass.

The valuable metal recovery facility of this embodiment includes a supply unit that supplies raw materials in the form of powder prepared by pre-treating waste batteries, and at least one flotation machine that is connected to the supply unit and floats and selects to remove graphite from a mixed solution of the supplied raw materials. , It may include a filtering unit connected to the flotation machine to filter and recover valuable metals leached in the solution discharged from the flotation machine.

The supply unit may include a pulverizer that crushes the waste battery and processes it into particles, and a sintering machine connected to the pulverizer that sinters the pulverized particles and processes them into powder.

It may further include a graphite recovery unit connected to the flotation machine to recover the graphite suspended and sorted from the flotation machine.

The flotation machine may include a first flotation machine connected to the supply unit to float and separate graphite, and a second flotation machine connected to the output side of the first flotation machine to float and separate the solution discharged from the first flotation machine to remove graphite. You can.

According to this embodiment, graphite is removed through a flotation process before the valuable metal leaching process and valuable metals are leached and recovered, thereby reducing the amount to be processed in the post-process, thereby reducing the load and shortening the processing time.

Productivity can be maximized by increasing the recovery efficiency of valuable metals.

In addition, by additionally recovering the graphite contained in the waste battery through the flotation process, it is possible to reduce costs and minimize pollution through recycling of discarded resources.

1 is a schematic diagram showing a waste battery valuable metal recovery facility according to this embodiment.
Figure 2 is a schematic diagram showing a process for recovering valuable metals from waste batteries according to this embodiment.

Hereinafter, embodiments of the present invention will be described in detail. However, this is presented as an example, and the present invention is not limited thereby, and the present invention is only defined by the scope of the claims to be described later. The embodiments described below may be modified into various forms without departing from the concept and scope of the present invention. As much as possible, identical or similar parts are indicated using the same reference numerals in the drawings.

The terminology used below is only for referring to specific embodiments and is not intended to limit the invention. As used herein, singular forms include plural forms unless phrases clearly indicate the contrary. As used in the specification, the meaning of "comprising" is to specify a specific characteristic, area, integer, step, operation, element and/or component, and to specify another specific property, area, integer, step, operation, element, component and/or group. It does not exclude the existence or addition of .

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. However, the following example is only a preferred example of the present invention and the present invention is not limited to the following example.

Hereinafter, this embodiment will be described as an example of a structure for recovering valuable metals from a lithium-ion battery (Li-ion battery). The present invention can be applied to all batteries that use graphite as a negative electrode material (or positive electrode material) in addition to lithium ion batteries.

In the following description, valuable metals are metal oxides used as cathode active materials and may refer to metals that are subject to recovery for recycling, including lithium. For example, valuable metals may be Cu, Mn, Ni, Co, Li, Fe, and Al.

Figure 1 schematically shows a waste battery valuable metal recovery facility of this embodiment.

As shown in FIG. 1, the recovery facility of this embodiment has a supply unit 10 that supplies raw materials in powder form manufactured by preprocessing waste batteries, and is connected to the supply unit 10 to extract graphite from a solution mixed with the supplied raw materials. It may include at least one flotation machine 20 that selects and removes flotation, and a filtering unit 30 connected to the flotation machine 20 to filter and recover valuable metals leached in the solution discharged from the flotation machine 20. You can.

Accordingly, before leaching and recovering the valuable metals, the graphite contained in the solution is removed by flotation using the flotation machine 20, thereby increasing the content of the valuable metals precipitated in the solution. Therefore, by reducing the overall throughput in the recovery process of valuable metals leached in solution, it is possible to reduce the load on filtering and increase productivity.

Waste batteries are largely composed of an anode, a cathode, and a separator, and contain components such as lithium oxide as a cathode active material, graphite as a cathode active material, and synthetic resins such as polyethylene or polypropylene used as a separator. Accordingly, the raw materials obtained by preprocessing waste batteries contain graphite, etc. in addition to the valuable metals that make up the positive electrode active material.

The supply unit 10 preprocesses the waste batteries into powdered raw materials and supplies them to the flotation machine 20.

In this embodiment, the supply unit 10 may include a pulverizer 12 that crushes the waste battery and processes it into particles, and a sintering machine 14 connected to the pulverizer 12 to sinter the pulverized particles and process them into powder. You can. Alternatively, the supply unit 10 may be a simple hopper structure that stores preprocessed raw materials provided from the outside and supplies them to the flotation machine 20 when necessary.

The shredder 12 can turn waste batteries into small-sized particles through a mechanical processing process. For example, the crusher 12 can reduce the size of waste batteries in the form of lumps into small particles through several stages such as crushing, shredding, or grinding. The shredder 12 can be modified in various ways as long as it can shred waste batteries to a set particle size.

The calciner 14 heat-treats particles obtained by pulverizing waste batteries to remove organic substances and manufactures them in powder form. Waste battery particles that have passed through the calciner 14 are removed by volatilizing organic substances such as synthetic resin forming the separator at high temperature, and are produced in the form of a powder that can be mixed into a solution.

The raw material in powder form produced through the calciner 14 is supplied to the flotation machine 20. The raw material supplied to the flotation machine 20 through the calciner 14 may have a particle size of more than 0 and less than or equal to 0.25 mm. Accordingly, the raw materials supplied to the flotation machine 20 can be effectively mixed with the solution contained in the flotation machine 20.

The flotation machine 20 of this embodiment removes graphite, which is an impurity, from the raw material supplied from the supply unit 10 and leaches valuable metals into the solution.

The raw materials supplied to the flotation machine (20) are mixed with the solution contained within the flotation machine (20). Among the raw materials, valuable metals are mixed in the solution and precipitate to the bottom, and graphite floats on the water surface along with air bubbles.

The flotation machine 20 contains a regulator for adjusting the hydrogen ion concentration (pH), a foaming agent for floating graphite, a catcher for adsorbing graphite to bubbles, or a floating inhibitor to prevent floating of valuable metals to float graphite. It may further include a component for supplying necessary ingredients for selection. Accordingly, if necessary, a control agent, foaming agent, catcher, flotation inhibitor, etc. can be added into the solution to create a graphite floating screening environment.

The flotation machine 20 may be equipped with a stirring blade 21 therein to generate bubbles by rotating the solution. Bubbles are generated in the solution by the rotational drive of the stirring blade 21, and the graphite floating in the solution floats on the water surface along with the bubbles due to the difference in specific gravity and can be selectively separated from the solution.

The equipment of this embodiment may further include a graphite recovery unit 40 that is connected to the flotation machine 20 and recovers the graphite suspended and sorted from the flotation machine 20. The graphite recovery unit 40 can be applied to any structure that separates graphite from air bubbles floating on the flotation machine 20.

Graphite suspended in the upper part of the flotation machine 20 by the graphite recovery unit 40 can be separated from the flotation machine 20 and recovered separately. Accordingly, by separately recovering graphite from waste batteries, it is possible to increase economic efficiency and minimize environmental pollution through recycling of resources that are not recycled and discarded.

In this way, by floating and removing graphite, which is an impurity, in a solution mixed with raw materials, it is possible to increase the content of valuable metals leached in the solution. Therefore, it is possible to filter valuable metals in the post-process and reduce the amount of sediment to be recovered, thereby reducing the process load and increasing the efficiency of valuable metal recovery, thereby maximizing productivity.

In this embodiment, the flotation machine 20 has a structure equipped with two flotation machines (hereinafter referred to as the first flotation machine 22 and the second flotation machine 24 for convenience of explanation) arranged sequentially. . The first flotation machine 22 and the second flotation machine 24 are arranged sequentially, so that the task of removing graphite, which is an impurity, can be performed continuously.

The second flotation machine 24 can be selectively driven when necessary. Accordingly, by operating only the first flotation machine 22 to remove graphite, or by additionally operating the second flotation machine 24 to further remove graphite as an impurity, the content of valuable metals in the precipitate of the solution can be further increased. .

This embodiment is not limited to a structure having two flotation machines, the first flotation machine 22 and the second flotation machine 24, and a structure in which three or four or more flotation machines are sequentially connected can also be applied.

Hereinafter, a structure in which the flotation machine 20 of this embodiment includes two first flotation machines 22 and two flotation machines 24 will be described as an example. The term flotation machine 20 may refer to both the first flotation machine 22 and the second flotation machine 24.

The first flotation machine 22 and the second flotation machine 24 may have the same structure. The first flotation machine 22 is connected to the supply unit 10 and can primarily float and sort graphite from the raw material supplied from the supply unit 10. The second flotation machine 24 is connected to the outlet side of the first flotation machine 22 and can secondaryly flotate graphite from the solution discharged from the first flotation machine 22.

The first flotation machine 22 and the second flotation machine 24 are connected to the graphite recovery unit 40, and the graphite suspended in the first flotation machine 22 and the second flotation machine 24 is transferred to the graphite recovery unit ( 40) and can be recovered.

In addition, the output sides of the first flotation machine 22 and the second flotation machine 24 are connected to the filtering unit 30, and the solution from which graphite is removed from the first flotation machine 22 or the second flotation machine 24 Can be supplied to the filtering unit 30.

The filtering unit 30 filters and recovers valuable metals from the sediment of the solution discharged from the flotation machine.

For example, the filtering unit 30 may include a filtration filter that filters out precipitates from the solution and may have a structure that filters valuable metals by pressurizing the solution with a filtration filter. Accordingly, as the solution supplied to the filtering unit 30 passes through the filter of the filtering unit 30, valuable metals that are precipitates do not pass through the filter and can be filtered and recovered. The filtering unit 30 may be modified in various ways as long as it filters the solution and filters out valuable metals precipitated in the solution.

As mentioned, the total amount of sediment to be filtered can be further reduced in the solution supplied to the filtering unit 30 in a state in which graphite, which is an impurity, has been removed. Accordingly, it is possible to reduce the load on the filtering unit 30 and maximize the efficiency of recovering valuable metals.

Hereinafter, the recovery process of this embodiment will be described with reference to FIG. 2.

Figure 2 shows a waste battery valuable metal recovery process according to this embodiment.

As shown, the valuable metal recovery process of this embodiment includes the steps of preparing raw materials in the form of powder pretreated from waste batteries, a flotation step of floating and screening the prepared raw materials at least once to remove graphite from the mixed solution, and the solution. It may include a filtering step of filtering and recovering valuable metals leached.

In the raw material preparation step, the raw materials may be prepared through a pulverizing step of pulverizing waste batteries and processing them into particles, and a sintering step of baking the pulverized particles and processing them into powder form.

In this embodiment, the raw material supplied to the flotation process may have a particle size of more than 0 and less than or equal to 0.25 mm. Preferably, the particle size of the raw material may be 0.1 to 0.2 mm. When the raw material particle size is 0.1 to 0.2 mm, graphite, an impurity, may float evenly in the solution. If the particle size of the raw material is outside the above appropriate range, it may affect the actual yield of valuable metals.

If the particle size of the raw material is smaller than 0.1 mm, the effect of mixing with the solution is not significant, and there is a problem that a lot of cost and time are spent on crushing the raw material during the raw material preparation process. If the particle size of the raw material exceeds 0.2mm, impurities and valuable metals cannot be separated. Accordingly, there is a problem in which the floating separation of graphite, which is an impurity, cannot be properly performed.

In the sintering step, the sintering temperature of the pulverized particles may be 650 to 700° C. When the firing temperature is less than 650°C, there is a problem of insufficient removal of organic substances from the active material. If the firing temperature exceeds 700°C, the active material is fired, which has a negative effect on the subsequent leaching process and reduces the leaching rate.

The flotation step may be performed multiple times. For example, the flotation step includes a first flotation step in which graphite is removed by first flotation from a solution mixed with raw materials, and a second flotation step in which graphite is removed by floating and sorting the solution that has passed through the first flotation step again. It can be included.

In the flotation stage, the content of valuable metals and graphite in the solution may be 5 to 35%. If the content of valuable metals and graphite in the solution is less than 5%, not only does the volume of the equipment increase and investment costs increase, but the amount of wastewater generated also increases. If the content of valuable metals and graphite in the solution exceeds 35%, there is a problem in that the graphite particles are not enough to be stirred with the solution and are not adsorbed to the bubbles.

Additionally, the pH of the solution in the flotation step may be 7 to 10. In this example, the pH of the solution can be adjusted by adding NaOH, Na2CO3, or H2SO4. If the pH of the solution is outside the above range, a problem may occur that reduces the activation of the graphite surface and prevents adsorption to bubbles.

In addition, in the flotation stage, a foaming agent for floating graphite, a catcher for adsorbing graphite to bubbles, or a floating inhibitor to prevent floating of valuable metals may be further added into the solution.

In this embodiment, the foaming agent may be at least one selected from MIBC (methyl isobutyl carbinol), pine oil, cresolic acid, alcohol, and kerosene.

The catcher may be at least one selected from xantate, aerofloat.

Additionally, the floating inhibitor may be at least one selected from starch, water, and glass.

By adding a foaming agent, catcher, or flotation inhibitor to the solution during the flotation process, the flotation and sorting effect of graphite can be further improved.

Through the flotation process, graphite mixed in the solution floats on the water surface and can be selectively removed. Graphite suspended in the flotation process can be recovered through a separate collection process.

Once the flotation process is completed, the impurity graphite is removed and the solution containing the valuable metals precipitated is transferred to a filtering process. Through the filtering process, valuable metals precipitated in the solution are recovered.

In this way, by flotation and removal of graphite mixed in raw materials before leaching and recovery of valuable metals from a solution mixed with waste battery powder according to this embodiment, valuable metals can be recovered more easily and effectively from the solution from which graphite has been removed. You can do it.

Although exemplary embodiments of the present invention have been shown and described as described above, various modifications and other embodiments will occur to those skilled in the art. These modifications and other embodiments are to be considered and included in the appended claims without departing from the true spirit and scope of the present invention.

10: supply unit 12: crusher
14: Calciner 20: Flotation machine
21: stirring wing 22: first flotation machine
24: second flotation machine 30: filtering unit
40: Graphite recovery unit

Claims (7)

Preparing raw materials in powder form pretreated from waste batteries,
A flotation step in which graphite is removed by flotation and screening at least once from a solution in which the prepared raw materials are mixed, and
Filtering step to filter and recover valuable metals leached in solution
Method for recovering valuable metals from waste batteries including. According to claim 1,
The flotation step includes a first flotation step in which graphite is removed by first flotation from a solution mixed with raw materials, and a second flotation step in which the solution that has passed through the first flotation step is again flotation and sorted to remove graphite. How to recover valuable metals from waste batteries. The method of claim 1 or 2,
In the flotation step, a method of recovering valuable metals from a waste battery, including the step of adding a catcher to adsorb graphite to the bubbles. According to claim 3,
A method of recovering valuable metals from a waste battery, wherein the catcher is at least one selected from xantate and aerofloat. A supply unit that supplies raw materials in the form of powder manufactured by pre-processing waste batteries,
At least one flotation machine connected to the supply unit to float and remove graphite from a solution mixed with the supplied raw materials, and
A filtering unit connected to the flotation machine to filter and recover valuable metals leached in the solution discharged from the flotation machine.
Waste battery valuable metal recovery equipment including. According to claim 5,
A waste battery valuable metal recovery facility further comprising a graphite recovery unit connected to the flotation machine to recover the graphite suspended and sorted from the flotation machine. According to claim 5,
The flotation machine includes a first flotation machine connected to the supply unit to float and sort the graphite, and a second flotation machine connected to the output side of the first flotation machine to float and sort the solution discharged from the first flotation machine to remove graphite. Waste battery valuable metal recovery facility.