JP7006438B2 - Melting separation device, method for separating aluminum from waste lithium-ion batteries, and method for recovering valuable resources from waste lithium-ion batteries - Google Patents

Description

The present invention relates to a melt separation device, a method for separating aluminum from a waste lithium ion battery using the melt separation device, and a method for recovering valuable resources.

In recent years, lithium-ion batteries have become widespread as lightweight, high-output secondary batteries. A lithium ion battery is a negative electrode material in which a negative electrode active material such as graphite is fixed to a negative electrode current collector made of copper foil inside an outer can made of metal such as aluminum or iron, and a positive electrode current collector made of aluminum foil. Electrolyte containing a positive electrode material to which a positive electrode active material such as lithium nickel oxide or lithium cobalt oxide is fixed, a separator made of a porous organic resin film of polypropylene, and an electrolyte such as lithium hexafluorophosphate (LiPF ₆ ). It has a structure in which a liquid or the like is sealed.

One of the main uses of lithium-ion batteries is hybrid and electric vehicles. The lithium-ion battery used for these becomes a waste lithium-ion battery when the automobile reaches the end of its life or the battery itself reaches the end of its life. Along with the life cycle of automobiles, it is expected that a large amount of lithium-ion batteries installed in automobiles will be discarded in the future.

Many proposals have been made to reuse such used batteries and defective products generated during manufacturing (hereinafter, these are collectively referred to as "waste lithium ion batteries") as resources. For example, in Patent Document 1, a waste lithium ion battery provided with an aluminum outer can is placed on a mesh body and heated at a temperature of about 660 ° C. or higher, which is the melting point of aluminum, to melt the aluminum material and form a mesh. A method has been proposed in which a molten aluminum material and a non-melting material are separated by dropping the aluminum material from the mesh of the body and leaving the non-melting material constituting the battery body on the network. ..

By the way, the waste lithium ion battery contains a lithium hexafluorophosphate solution in the electrolytic solution, and may have a charge remaining, and the heat treatment tends to cause an explosion or ignition. Further, in the case of an explosion, there is a problem that a part of the positive electrode material containing a valuable metal in the outer can is crushed and integrated with the aluminum melted by heating, so that it cannot be separated and recovered.

Further, in the method of dropping molten aluminum from the mesh of the mesh and separating it by using a mesh as in the method described in Patent Document 1, the powder constituting the positive electrode material easily drops from the mesh. May mix with aluminum. If such mixing occurs, recovery loss of valuable nickel and cobalt will occur, and the purity of aluminum will also decrease, which is not preferable for any of them.

Further, when heated at a high temperature exceeding 900 ° C., there is a problem that lithium contained in the electrode body exudes to the outside of the electrode body, adheres to the inside of the furnace, and separates from the electrode body. When the electrode body is to be melted and processed by a dry method in a subsequent step, lithium has the effect of lowering the melting point of the slag, but when the lithium seeps out of the electrode body and is lost, the melting point rises and energy is generated. It is not preferable because the cost increases and the damage of the furnace is promoted.

In this way, when recovering valuable metals from waste lithium-ion batteries, it is necessary to efficiently separate the aluminum that constitutes the exterior without separating valuable resources such as lithium, copper, and nickel contained in the electrode body. There is a need for a pretreatment method that enables it.

Japanese Unexamined Patent Publication No. 2017-4920

The present invention has been proposed in view of such circumstances. For example, when recovering valuable resources contained in an electrode body in a waste lithium ion battery, the components constituting the exterior of the battery and the like are efficiently used. Provided is a method capable of separating and suppressing recovery loss of valuable materials.

As a result of diligent studies to solve the above-mentioned problems, the present inventor uses a specific melting and separating device having a partition plate having an inclined surface inclined in a predetermined direction inside to generate a waste lithium ion battery. We have found that only aluminum can be efficiently separated by heating to melt aluminum, and have completed the present invention.

(1) The first invention of the present invention uses a melting separation device divided into an upper part and a lower part by a partition plate having an inclined surface inclined in a predetermined direction, and waste lithium containing aluminum on the partition plate. The aluminum of the waste lithium ion battery is melted by placing an ion battery and heating the inside of the melting separation device so that the temperature inside the melting separation device is in the range of 700 ° C. or higher and 900 ° C. or lower. It is a method of separating aluminum from a waste lithium ion battery, which separates the aluminum by flowing out from an opening formed at the lowest portion of an inclined surface of a partition plate and collecting the aluminum in the lower part of the melting separation device.

(2) In the second invention of the present invention, in the first invention, the waste lithium ion battery is detoxified and roasted in advance, and the waste lithium ion battery after the detoxification roasting treatment is melt-separated. This is a method for separating aluminum from a waste lithium-ion battery, which is placed on the partition plate of the device.

(3) The third aspect of the present invention is a method for recovering valuable resources from a waste lithium ion battery, which comprises an aluminum separation step for carrying out the method according to claim 1. This is a method for recovering valuable resources from batteries.

(4) The fourth invention of the present invention includes a container having a lid and a partition plate provided inside the container and dividing the container into an upper part and a lower part, and the partition plate is a predetermined one. It has an inclined surface inclined in the direction of the above, an opening is formed at the lowest portion of the inclined surface, a substance containing a component to be melt-separated is placed on the partition plate, and the inside of the container is the inside of the container. The component to be melt-separated is heated to a temperature at which it can be melted, and the component melted by heating flows out from the opening formed on the inclined surface of the partition plate and is recovered at the lower part of the container. , A melting and separating device.

(5) The fifth aspect of the present invention is the melt separation device for melting and separating aluminum contained in a waste lithium ion battery in the fourth invention.

(6) The sixth invention of the present invention is the melting separation device in which the opening is smaller than the minimum width of the substance placed on the partition plate in the fourth or fifth invention.

(7) In the seventh aspect of the present invention, in any one of the fourth to sixth inventions, the lower portion of the container is a melting separation device composed of a dish-shaped body.

(8) In the eighth aspect of the present invention, in any one of the fourth to seventh inventions, the partition plate is a melting separation device having a smooth inclined surface.

(9) The ninth aspect of the present invention is the melting separation device in which in any of the fourth to seventh inventions, the partition plate has striped protrusions formed on the inclined surface.

According to the present invention, for example, when recovering valuable resources contained in an electrode body in a waste lithium ion battery, components such as aluminum constituting the exterior of the battery can be efficiently separated, and the valuable resources can be separated. Recovery loss can be suppressed.

It is a figure which shows the structure of the melting separation apparatus which concerns on 1st Embodiment. It is a figure which shows the structure of the melting separation apparatus which concerns on 2nd Embodiment. It is a figure which shows the structure of the melting separation apparatus which concerns on 3rd Embodiment. It is a figure which shows the structure of the melting separation apparatus which concerns on 4th Embodiment. It is a figure which shows the structure of the melting separation apparatus which concerns on 5th Embodiment.

Hereinafter, a specific embodiment of the present invention (hereinafter, referred to as “the present embodiment”) will be described in detail. The present invention is not limited to the following embodiments, and various modifications can be made without changing the gist of the present invention. Further, in the present specification, the notation "X to Y" (X and Y are arbitrary numerical values) means "X or more and Y or less".

≪1. Overview ≫
The method for separating aluminum according to the present invention is a method for separating aluminum composed of, for example, an exterior material in a waste lithium ion battery. Therefore, this method can also be defined as a method for disassembling a waste lithium ion battery that separates and removes an exterior made of aluminum from the waste lithium ion battery.

Even if the exterior material of the waste lithium ion battery is not composed of aluminum, if aluminum is contained as the internal material of the battery, the separation method according to the present invention is intended to separate the aluminum of the internal material. Can be applied. In that case, aluminum, which is an internal material, can be effectively separated by breaking a part of the exterior and making a hole or the like.

This separation method is used in the aluminum separation step of separating the aluminum constituting the exterior in the process of recovering valuable resources (valuable metals) such as lithium, copper, nickel, and cobalt contained in the electrode body of the waste lithium ion battery. Can be applied.

If aluminum can be effectively separated in the aluminum separation step in the precious metal recovery process, it is a high-purity valuable resource that suppresses the mixing of aluminum when separating and recovering the valuable material from the electrode body in the subsequent step. Can be recovered. Further, in the aluminum separation step, the recovery loss of the valuable material can be reduced by processing while suppressing the separation of a part of the valuable material to be recovered together with the aluminum.

Specifically, in the method for separating aluminum according to the present invention, first, a melting separation device divided into an upper part and a lower part by a partition plate having an inclined surface inclined in a predetermined direction is used, and aluminum is placed on the partition plate. Place a waste lithium-ion battery containing. Next, the aluminum contained in the waste lithium ion battery is melted by heating so that the temperature inside the melting separation device is in the range of 700 ° C. or higher and 900 ° C. or lower. Then, the aluminum melted by heating is discharged from the opening formed at the lowest portion of the inclined surface of the partition plate and collected at the lower part of the melting separation device to separate the aluminum.

According to such a method, the molten aluminum can be efficiently separated and recovered, and valuable resources contained in the electrode body and the like can be prevented from being mixed in the molten aluminum. As a result, in the process of recovering valuable resources from the waste lithium ion battery, the recovery loss of the valuable resources can be effectively reduced.

≪2. Recovery process of valuable resources from waste lithium-ion batteries ≫
First, prior to the description of a more specific aluminum separation method, a process for recovering valuable resources from a waste lithium ion battery to which the separation method can be applied as a pretreatment step (aluminum separation step) will be described.

The valuable resource recovery process includes, for example, a pretreatment step S1 for removing the electrolytic solution and the exterior of the waste lithium ion battery, a crushing step S2 for crushing the contents of the battery into crushed products, and oxidative roasting of the crushed products. It has an oxidative roasting step S3 and a reduction melting step S4 for reducing and melting the oxidative roasted product to form an alloy. The process of recovering valuable resources having each of these steps is merely an example, and is not limited thereto.

Here, this valuable resource recovery process targets a waste lithium-ion battery having an exterior containing aluminum.

[Pretreatment process (aluminum separation process)]
In the pretreatment step S1, the exterior constituting the waste lithium ion battery is removed. As described above, the exterior of the waste lithium-ion battery to be treated is made of aluminum.

As described above, by passing through the pretreatment step S1 for separating and removing the aluminum as the exterior, the aluminum can be recovered as a valuable resource relatively easily. In addition, when recovering valuable resources contained in the electrode body arranged in the exterior in the next step or later, aluminum, which is a physical obstacle to recovery, can be removed. In addition, it is possible to prevent aluminum from being mixed with the valuable resources contained in the electrode body and reduce the purity, and to improve the recovery productivity.

Although the details will be described later, in this pretreatment step S1, the aluminum separation method according to the present invention can be applied. Specifically, aluminum is separated and removed by a separation process using a melting separation device described later. As a result, aluminum can be efficiently separated and removed, and the recovery loss of valuable resources contained in the electrode body can be reduced.

Prior to separating and removing the aluminum on the exterior, the waste lithium ion battery can be subjected to a detoxification roasting treatment by heating it at a predetermined temperature to make it harmless. Further, the battery may be physically opened with a needle-shaped cutting edge to allow the internal electrolytic solution to flow out and be removed. As a result, for example, it is possible to more effectively prevent the occurrence of an explosion or the like caused by the electrolytic solution, and it is possible to enhance safety.

[Crushing process]
In the pulverization step S2, the contents of the battery from which the aluminum on the exterior has been separated and removed through the pretreatment step S1 are pulverized to obtain a pulverized product. The treatment in the crushing step S2 is performed for the purpose of increasing the reaction efficiency in the dry smelting process after the next step, and by increasing the reaction efficiency, the recovery rate of valuable resources such as copper, nickel and cobalt is increased. Can be done. The crushing method is not particularly limited, but can be performed using a conventionally known crusher such as a cutter mixer.

[Oxidation roasting process]
In the oxidative roasting step S3, the pulverized product is oxidatively roasted to obtain an oxidative roasted product. In the oxidative roasting step S3, carbon contained in the contents of the battery is oxidized and removed.

As described above, in the oxidative roasting step S3, carbon contained in the contents of the battery can be removed by oxidatively roasting the pulverized product, and as a result, locally in the reduction melting step S4 of the next step. The generated molten particles of reduced valuables can be aggregated without physical damage due to carbon, and can be recovered as an integrated alloy. Further, in the reduction melting step S4, it is possible to prevent phosphorus contained in the contents of the battery from being reduced by carbon, effectively oxidatively remove phosphorus, and suppress distribution of phosphorus in an alloy of valuable resources. ..

The temperature of the oxidative roasting treatment (oxidative roasting temperature) can be, for example, 600 ° C. or higher. By setting the oxidative roasting temperature to 600 ° C. or higher, carbon contained in the battery can be effectively oxidized and removed. Further, the processing time can be shortened by preferably setting the oxidative roasting temperature to 700 ° C. or higher. Further, the upper limit of the oxidative roasting temperature is preferably 900 ° C. or lower, whereby the heat energy cost can be suppressed and the processing efficiency can be improved.

The oxidative roasting treatment can be performed using a known roasting furnace. As the roasting furnace, all types of kilns can be used, and rotary kilns, tunnel kilns (hearth furnaces) and the like can be preferably used.

[Reduction melting process]
In the reduction melting step S4, the oxidative roasted product obtained in the oxidative roasting step S3 is reduced and melted to obtain an alloy (reduced product) containing slag and valuable resources. In the reduction melting step S4, unnecessary oxides composed of impurities obtained by oxidation in the oxidation roasting treatment remain as oxides, and valuable materials such as copper that have been oxidized in the oxidation roasting treatment. The oxide is reduced and melted, and the reduced product is recovered as an integrated alloy. The alloy obtained as a melt is also referred to as "fused gold".

In the reduction melting step S4, it is preferable to perform the reduction melting treatment in the presence of at least carbon. Carbon is a reducing agent capable of easily reducing valuable resources such as copper, nickel, and cobalt to be recovered. Therefore, by performing reduction melting in the presence of carbon as a reducing agent, valuable resources can be efficiently reduced and an alloy containing the valuable resources can be obtained more effectively.

The temperature of the melting treatment (melting temperature) is, for example, preferably in the range of 1320 ° C. or higher and 1600 ° C. or lower, and more preferably in the range of 1450 ° C. or higher and 1550 ° C. or lower. By melting at a temperature of 1320 ° C. or higher, valuable resources such as copper, nickel, and cobalt can be easily recovered as fused gold. Further, when melted at 1450 ° C. or higher, the fluidity of the fused gold becomes very good, and the separation efficiency between the impurity component and the valuable resource is improved, which is more preferable.

In the reduction melting treatment, it is preferable to use an oxide-based flux. By performing a reduction melting treatment using an oxide-based flux, slag containing an oxide of an impurity component can be dissolved in the flux and removed. Examples of the oxide-based flux include calcium oxide, silicon oxide, magnesium oxide, iron oxide and the like having a melting point of 1500 ° C. or lower. Further, in the reduction melting treatment, calcium fluoride or the like can be added to lower the melting point of the slag, whereby the energy cost can be reduced.

≪3. Aluminum separation method ≫
The method for separating aluminum according to the present invention can be applied to the pretreatment step (aluminum separation step) S1 in the method for recovering valuable resources from the waste lithium ion battery described above, and the aluminum on the exterior constituting the battery. Is melted and separated. The molten aluminum is also referred to as "fused aluminum".

Specifically, the method for separating aluminum is characterized in that it is carried out by using a melting separation device divided into an upper part and a lower part by a partition plate having an inclined surface inclined in a predetermined direction.

<3-1. Melting separation device>
(1) First Embodiment FIG. 1 is a diagram showing the configuration of a melting separation device 1 according to the first embodiment, (A) is a cross-sectional view from the front, and (B) is a partition plate. It is a figure when viewed from the top surface (the figure when the partition plate 12 is seen from the upper part of a container with the lid 11a of a container 11 removed). The waste lithium ion battery containing aluminum to be melt-separated is indicated by reference numeral "B". Further, the molten aluminum obtained by melting by heating is indicated by the reference numeral "M".

The melting separation device 1 includes a container 11 having a lid 11a, and a partition plate 12 provided inside the container 11 for dividing the container 11 into an upper portion and a lower portion. The partition plate 12 has an inclined surface 12s inclined in a predetermined direction, and is characterized in that an opening 12h is formed at the lowest portion of the inclined surface 12s.

[container]
The container 11 is, for example, a heat-resistant container having a cylindrical shape. The container 11 is charged with a waste lithium ion battery B containing aluminum, which is the target of fusion separation, in the exterior. It should be noted that such a waste lithium ion battery B is also referred to as a “charge B” for charging the waste lithium ion battery B into the container 11.

Further, the container 11 is heated from the outside by a heating device or the like, and the temperature inside the container 11 is heated to a predetermined temperature, that is, a temperature at which the outer aluminum contained in the charge can be sufficiently melted. Here, the heating method is not particularly limited, and for example, a method using fuel combustion heat energy, a heating method using an oil burner, a gas burner, a radiant tube, etc., a method using electric energy, and direct energization of a heating element. A method of utilizing the Joule heat generated by the Joule heat generated by the burner and the Joule heat generated by the induced vortex current from the external coil can be mentioned.

The heat-resistant container 11 itself may be a combustion furnace that uses the heat of combustion energy of the fuel or an electric furnace that uses the electric energy. Alternatively, a batch-type heating furnace in which the heat-resistant container 11 is heated in a stationary state in a box-shaped furnace, a trolley-type heating furnace in which the container 11 is placed on a trolley and continuously heated while moving in the furnace, the container 11 It is also possible to heat by using a belt type heating furnace or the like which continuously heats while moving the inside of the furnace by placing the above on a belt.

The container 11 has a lid 11a at the top. When the lid 11a is removed, the upper part of the container 11 is opened, and the charge B can be charged on the partition plate 12 provided inside through the opening. On the other hand, since the container 11 is heated to a predetermined temperature as described above, it is possible to form a closed space by having the lid 11a, and it is possible to improve the heating efficiency. Further, by making the inside of the container 11 a closed space by the lid 11a, it becomes easy to fill the inside with carbon dioxide gas by heating, the oxidation of the molten aluminum is suppressed, and the aluminum can be separated more efficiently. can.

The container 11 is preferably made of a material having high heat resistance. Among them, by constructing the container 11 with austenitic stainless steel, the high temperature strength is increased and deformation due to heating can be suppressed, and deterioration due to corrosion can be suppressed even if it is used multiple times, thereby improving durability. Can be done. Furthermore, since the generation of rust can be suppressed by using austenitic stainless steel, there is no risk that the rust will fall due to deterioration over time and contaminate the molten aluminum. The partition plate 12 and the molten aluminum receiving portion 13, which will be described later, can also be made of the same material.

[Partition plate]
The partition plate 12 is a plate-shaped member provided inside the container 11, and is a disk-shaped member that divides the inside of the cylindrical container 11 into an upper part (upper space) and a lower part (lower space). The partition plate 12 has an inclined surface 12s inclined in a predetermined direction, and is characterized in that an opening 12h is formed at the lowest portion of the inclined surface 12s.

Here, the lowest portion of the inclined surface 12s means a portion where the height in the height direction of the inclined surface 12s inclined in a predetermined direction is the lowest. Further, the opening 12h formed at the lowest portion thereof is smaller than the minimum width of the waste lithium ion battery (charged material) B charged in the container 11 and placed on the partition plate 12. Therefore, after being charged into the container 11, the charged material B does not fall from the partition plate 12 through the opening 12h before the aluminum is melted.

In the partition plate 12, a waste lithium ion battery containing aluminum is placed on the inclined surface 12s, and aluminum melted by heating in a predetermined temperature range is formed on the inclined surface 12 along the inclined direction of the inclined surface 12s. Flows. The inclined surface 12s is, for example, a smooth surface, and can be rephrased as a flow surface in which molten aluminum flows along the inclination. Therefore, the partition plate 12 is different from the reticulated body in which the mesh is regularly arranged.

In the melting separation device 1 according to the first embodiment, the partition plate 12 has an inclined surface 12s inclined in one direction. Specifically, as shown in FIG. 1 (A), the inclined surface 12s of the partition plate 12 is inclined so as to descend from the right side to the left side of FIG. 1 (A). Therefore, the inclination direction of the partition plate 12 is only one direction, and the aluminum placed on the partition plate 12 and melted by heating has a low height of the inclined surface (flow surface) 12s due to gravity (FIG. 1). It falls while flowing in the direction indicated by the arrow in (B). Then, the molten aluminum flows out from the opening 12h formed at the lowest portion of the inclined surface 12s.

The molten aluminum flowing out through the opening 12h falls into the lower space of the container 11 and is collected at the bottom of the lower space (the bottom of the container 11).

Here, for example, when a waste lithium ion battery is placed on a “reticulated body” having a mesh (see Patent Document 1) to melt aluminum, the battery is detoxified and roasted and the electrode body is damaged or the temperature rises. In a battery that explodes or ignites inside, the positive electrode particles generated by the damage of the electrode body easily fall through the mesh due to the flow of molten aluminum or the vibration generated by the movement of the container. .. As a result, even the valuable material contained in the positive electrode grain is separated together with the molten aluminum, resulting in a recovery loss of the valuable material.

On the other hand, in the melting separation device 1, the waste lithium ion battery B is placed on the partition plate 12 having the inclined surface 12s to melt the aluminum, so that the container 11 is immediately generated even if the positive electrode grain is generated. Does not fall into the lower space of. Further, since the charge B is placed on the partition plate 12, the generated positive electrode material grains are caught on the large electrode body while moving on the partition plate 12, and easily reach the opening 12h. There is nothing to do. Therefore, according to such a melting separation device 1, it is possible to effectively reduce the recovery loss of valuable resources.

[Fused aluminum receiving part]
The molten aluminum receiving portion 13 is a receiving member that flows along the inclined surface 12s of the partition plate 12 along the inclined direction and receives the molten aluminum flowing out through the opening 12h formed at the lowest portion of the inclined surface 12s. .. The molten aluminum receiving portion 13 can be formed of, for example, a dish-shaped body.

FIG. 1A shows an example in which the molten aluminum receiving portion 13 is integrally configured with the container 11. As shown in FIG. 1A, the molten aluminum receiving portion 13 is formed of a dish-shaped body, and is fitted to the container 11 at a predetermined position. Further, the molten aluminum receiving portion 13 is not limited to the embodiment integrally configured with the container 11, for example, as in the fusion separation device 4 according to the fourth embodiment described later (see FIG. 4A). The molten aluminum receiving portion 13 made of a dish-shaped body may be provided separately from the container 11, and the container 11 having an open bottom may be fitted inside the molten aluminum receiving portion 13.

(2) Second Embodiment FIG. 2 is a diagram showing the configuration of the melting separation device 2 according to the second embodiment, (A) is a cross-sectional view from the front, and (B) is a partition plate. It is a figure when viewed from the top surface (the figure when the partition plate 12 is seen from the upper part of a container with the lid 11a of a container 11 removed). The functions of the members constituting the melting separation device 2 including the partition plate 12 are the same as the configuration of the melting separation device 1 according to the first embodiment, and the same reference numerals are given to the description thereof. Is omitted.

The melting separation device 2 includes a container 11 having a lid 11a, and a disk-shaped partition plate 12 provided inside the cylindrical container 11 and dividing the container 11 into an upper portion and a lower portion. Further, the partition plate 12 has an inclined surface 12s inclined in a predetermined direction, and an opening 12h is formed at the lowest portion of the inclined surface 12s.

In the melting separation device 2, the partition plate 12 has a so-called tapered shape (FIG. 2A) having an inclined surface 12s that inclines downward toward the central portion when viewed from above (see FIG. 2B). )). Therefore, the central portion of the inclined surface 12s of the partition plate 12 is the lowest portion, and the opening portion 12h is formed in the central portion thereof.

In such a melting separation device 2, the inclination direction of the partition plate 12 is one direction downward from the peripheral edge portion of the partition plate 12 to the central portion, and the charge B is placed on the partition plate 12. The aluminum M melted by heating falls while flowing in the direction in which the height of the inclined surface (flowing surface) 12s is low (the direction indicated by the arrow in FIG. 2B) due to gravity. Then, the molten aluminum M flows out from the opening 12h formed in the lowest portion of the inclined surface 12s (the central portion when the partition plate 12 is viewed from above).

(3) Third Embodiment FIG. 3 is a diagram showing the configuration of the melting separation device 3 according to the third embodiment, (A) is a cross-sectional view from the front, and (B1) and (B2). Is a view when the partition plate is viewed from the upper surface (a view when the partition plate 12 is viewed from the upper part of the container with the lid 11a of the container 11 removed). The functions of the members constituting the melting separation device 3 including the partition plate 12 are the same as the configuration of the melting separation device 1 according to the first embodiment, and the same reference numerals are given to the description thereof. Is omitted.

The melting separation device 3 includes a container 11 having a lid 11a, and a disk-shaped partition plate 12 provided inside the cylindrical container 11 and dividing the container 11 into an upper portion and a lower portion. Further, the partition plate 12 has an inclined surface 12s inclined in a predetermined direction, and an opening 12h is formed at the lowest portion of the inclined surface 12s.

In the melting separation device 3, the partition plate 12 has a mountain-shaped shape (see FIG. 3A) when viewed in cross section, and is downward from the top of the mountain shape toward the peripheral edge of the partition plate 12. It has an inclined surface 12s (12s') that is inclined to. Therefore, the peripheral edge portion of the partition plate 12 becomes the lowest portion of the inclined surface 12s, and the opening portion 12h is formed there.

Here, FIG. 3 (B1) is a top view of the partition plate 12 having a shape that is bent into a mountain shape so as to form a symmetrical half circle. In the partition plate 12 shown in FIG. 3 (B1), the bent portion becomes a linear top portion and has inclined surfaces 12s and 12s' that are directed downward toward the peripheral edge portion. The aluminum M, in which the charge B is placed on the partition plate 12 and melted by heating, has an inclined surface (flow surface) 12s due to gravity in the direction in which the height is low (arrows in FIG. 3 (B1)). It falls while flowing in each direction). Then, the molten aluminum M flows out from the opening 12h formed in the lowest portion (peripheral portion of the partition plate 12) of the inclined surface 12s.

Further, FIG. 3B2 is a top view of the partition plate 12 having a mountain-shaped shape with the central portion as the apex when viewed from above. The partition plate 12 shown in FIG. 3B2 has an inclined surface 12s that downwards from the apex of the mountain shape toward the peripheral edge portion of the partition plate 12. The aluminum in which the charge B is placed on the partition plate 12 and melted by heating is indicated by an arrow in the direction in which the height of the inclined surface (flow surface) 12s is low due to gravity (FIG. 3 (B2)). It falls while flowing in each direction). Then, the molten aluminum flows out from the opening 12h formed in the lowest portion (peripheral portion of the partition plate 12) of the inclined surface 12s.

(4) Fourth Embodiment FIG. 4 is a diagram showing the configuration of the melting separation device 4 according to the fourth embodiment, (A) is a cross-sectional view from the front, and (B) is a partition plate. It is a figure when viewed from the top surface (the figure when the partition plate 12 is seen from the upper part of a container with the lid 11a of a container 11 removed). The functions of the members constituting the melting separation device 4 including the partition plate 12 are the same as the configuration of the melting separation device 1 according to the first embodiment, and the same reference numerals are given to the description thereof. Is omitted.

The melting separation device 4 includes a container 11 having a lid 11a, and a disk-shaped partition plate 12 provided inside the cylindrical container 11 and dividing the container 11 into an upper part and a lower part. Further, the partition plate 12 has an inclined surface 12s and an inclined surface 12s' that are inclined in a predetermined direction, and an opening 12h is formed at the lowest portion of the inclined surface 12s and the inclined surface 12s'.

In the melting separation device 4, the disk-shaped partition plate 12 has a ring-shaped opening 12h on the surface thereof (see FIG. 4B). The partition plate 12 has an inclined surface 12s that inclines downward from the peripheral edge portion toward the opening portion 12h. Further, the partition plate 12 has a mountain-shaped shape with the central portion as the top in the vicinity of the disk-shaped central portion (the portion from the central portion to the opening 12h), and faces the opening 12h from the top of the mountain shape. It has a downwardly inclined surface 12s'. As described above, the partition plate 12 in the melting separation device 4 has two types of inclined surfaces 12s and 12s', and the opening portion 12h formed at the downwardly inclined tip of the inclined surfaces 12s and 12s'. Are common.

In such a melting separation device 4, when the charge B is placed on the inclined surface 12s of the partition plate 12, the aluminum M melted by heating has a direction in which the height of the inclined surface (flow surface) 12s is low due to gravity. That is, it falls while flowing in the direction from the peripheral edge portion toward the opening portion 12h (the direction indicated by the arrow in FIG. 4B). Further, when the charge B is placed on the inclined surface 12s'in the partition plate 12, the aluminum M melted by heating becomes a mountain shape in the direction in which the height of the inclined surface (flow surface) 12s' is low due to gravity. It falls while flowing in the direction from the central portion to the opening 12h (the direction indicated by the arrow in FIG. 4B). Then, the molten aluminum M flows out from the opening 12h (substantially ring-shaped opening 12h) formed at the lowest portion of the inclined surfaces 12s and 12s'.

(5) Fifth Embodiment FIG. 5 is a diagram showing the configuration of the melting separation device 5 according to the fifth embodiment, and (A) and (B) are sectional views from the front. The functions of the members constituting the melting separation device 4 including the partition plate 12 are the same as the configuration of the melting separation device 1 according to the first embodiment, and the same reference numerals are given to the description thereof. Is omitted.

In the melting separation devices 5 and 5', in the partition plate 12, a plurality of striped protrusions are formed on the inclined surface 12s on which the charge B is placed, in other words, the flowing surface on which the molten aluminum M flows along the inclination. (Striped protrusions) 12p are formed (see FIGS. 5A and 5B). For example, such a partition plate 12 can be made of a striped steel plate. The partition plate 12 has, for example, an inclined surface 12s that inclines downward from the peripheral portion (outside) to the central portion (inside), and the surface of the inclined surface 12s has a striped protrusion. It forms 12p.

In such a melting separation device 5, when the charge B is placed on the inclined surface 12s, the aluminum M melted by heating has the gaps between the striped protrusions 12p on the inclined surface 12. It will flow along and flow out from the opening 12h at the end of the downward slope. On the other hand, for example, even if the electrode body is damaged for some reason and the electrode body particles (positive electrode material grains or the like) containing valuable resources are exposed, the generated solid electrode body particles are formed on the inclined surface 12s. It does not easily reach the opening 12h because it gets caught in the striped protrusions 12p and the gaps. Therefore, according to the melting separation device 5 in which the protrusions 12p are formed on the inclined surface 12s, it is possible to prevent the electrode body grains containing valuable resources from being separated together with the molten aluminum M even when the electrode body grains are generated. Therefore, the recovery loss of valuable resources can be reduced more effectively.

Here, FIG. 5A shows an example (melting separation device 5) in which the partition plate 12 is provided so as to be joined to the inner wall of the cylindrical container 11. Further, FIG. 5B shows an example (melting) of the partition plate 12 in which the leg portion 12f is provided and the partition plate (partition plate body) 12 having the leg portion 12f is installed inside the container 11. Separator 5') is shown. Even in the melting separation device 5'shown in FIG. 5B, in the container 11, the upper part (above the inclined surface 12s of the partition plate 12) and the lower part (inclined of the partition plate 12) are provided by the partition plate 12. It is divided into a portion below the surface 12s and surrounded by the legs 12f).

The partition plate 12 having the leg portion 12f shown in FIG. 5B is not limited to the application to the one in which the striped protrusions 12p are formed on the inclined surface 12s, and for example, the above-mentioned first embodiment is applied. The partition plate 12 of the melting separation devices 1 to 4 shown in the fourth embodiment from the embodiment may also have a configuration having the leg portion 12f in the same manner.

<3-2. How to separate aluminum from waste lithium-ion batteries>
As a pretreatment (pretreatment step S1) for recovering valuable resources from the waste lithium ion battery, the aluminum constituting the exterior of the waste lithium ion battery is effectively used in the above-mentioned melting separation device 1 (1 to 5). Can be separated into.

In the following, an example will be shown in which the "melting separation device 1" according to the first embodiment described above is used as the melting separation device, but the present invention is not limited to this.

Specifically, in this aluminum separation method, first, a melting separation device 1 divided into an upper part and a lower part by a partition plate 12 having an inclined surface 12s inclined in a predetermined direction is used, and the aluminum is separated onto the partition plate 12. , A waste lithium-ion battery B containing aluminum is placed.

In the melting separation device 1, as described above, the partition plate 12 that divides the inside of the container 11 is provided with an inclined surface 12s, and the waste lithium ion battery B containing aluminum is on the inclined surface 12s of the partition plate 12. It is placed in. At this time, as the waste lithium ion battery B to be charged into the melt separation device 1, it is preferable to charge the waste lithium ion battery B which has been subjected to the detoxification roasting treatment in advance, and the waste lithium after such the detoxification roasting treatment is preferably charged. The ion battery B is placed on the inclined surface 12s of the partition plate 12. The waste lithium ion battery B after the detoxification roasting treatment is in a state where the aluminum exterior remains almost as it is, and such a waste lithium ion battery B is placed on the partition plate 12.

When the waste lithium ion battery B is placed on the partition plate 12, the waste lithium ion battery B is subjected to a detoxifying roasting treatment to prevent an explosion, ignition, or the like. More specifically, in the melting separation device 1, as will be described later, since the aluminum is heated at a temperature exceeding the melting point, there is a possibility that an explosion or ignition may occur due to such a rapid rise to a high temperature. By performing a detoxification roasting treatment that heats at a predetermined temperature in advance, it is possible to suppress the occurrence of such an explosion or ignition. Further, it is possible to prevent the fusion separation device 1 from being deformed due to an explosion or the like and the fragments of the electrode body constituting the waste lithium ion battery B from being blown off, thereby improving the safety of the separation process and being a valuable resource. It also contributes to the prevention of recovery loss of valuable resources in the recovery process.

Next, in the aluminum separation method, the temperature inside the melting separation device 1 in which the waste lithium ion battery B is charged is heated so as to be in the range of 700 ° C. or higher and 900 ° C. or lower, whereby the waste lithium ion battery is heated. The aluminum constituting the exterior of B and the like is melted.

The aluminum constituting the exterior and the like has a melting point of about 660 ° C., and the waste lithium ion battery inserted by heating the aluminum so that the temperature inside the melting separation device 1 is 700 ° C. or higher, which exceeds the melting point. Aluminum is effectively melted from B. The upper limit of the heat treatment temperature is 900 ° C. or lower. Here, since the melting points of copper, nickel, cobalt, etc., which are valuable resources contained in the electrode body, are 1000 ° C. or higher, the temperature inside the melting separation device 1 should be in the range of 700 ° C. or higher and 900 ° C. or lower. By heating to, while melting aluminum, valuable resources such as copper, nickel, and cobalt can remain as solids.

Then, in the aluminum separation method, the aluminum melted by heating is discharged from the opening 12h formed at the lowest portion of the inclined surface 12s of the partition plate 12 in the melting separation device 1 and collected at the lower part of the melting separation device 1. Separates the aluminum.

As described above, in the melting separation device 1, the inclined surface 12s on which the waste lithium ion battery B is placed is inclined in a predetermined direction. Specifically, as shown in FIG. 1 (A), the inclined surface 12s of the partition plate 12 is inclined so as to descend from the right side to the left side of FIG. 1 (A). Therefore, the aluminum M melted by heating falls while flowing in the direction in which the height of the inclined surface 12s is low (the direction indicated by the arrow in FIG. 1B) due to gravity, and the inclined surface 12s falls. It flows out from the opening 12h formed at the lowest portion of the.

On the other hand, valuable resources such as copper, nickel, and cobalt that are not melted by heating remain on the partition plate 12 as a solid electrode body. In this way, only the aluminum constituting the exterior and the like is separated from the waste lithium ion battery B.

Hereinafter, examples of the present invention will be described in more detail, but the present invention is not limited to the following examples.

<< Examples and Comparative Examples >>
In the examples and comparative examples, the electrode body was formed by using a square waste lithium ion battery (length 140 mm × width 60 mm × thickness 12 mm, substantially rectangular parallelepiped shape) for automobiles so as to have the configuration shown in Table 1 below. A melt removal test was conducted on the aluminum outer can to be stored.

Specifically, a tabletop high-temperature electric furnace (made by Denken Hydental Co., Ltd., KDF-1700) (denoted as "tabletop furnace" in Table 1) using a cantal super as a heating element, or an upper part using a siliconite as a heating element. A large crucible furnace made of brick (denoted as "crucible furnace" in Table 1) is used, and a container (melting separation device) as shown in the schematic diagram of Fig. 1 etc. is installed in those furnaces. The temperature inside the melting separation device was heated to 700 ° C. and held for 30 minutes. In the crucible furnace, the upper opening was covered with a refractory material (RCF free board manufactured by ITM Co., Ltd.) for treatment.

Here, as the waste lithium-ion battery to be processed, the "semi-finished product" assembled by the battery maker until just before the electrode body is inserted into the aluminum outer can and the electrolytic solution is put in, and the electrolytic solution is inserted and charged. Two types of waste batteries, a "detoxified roasted product", in which used waste batteries after repeated discharges were roasted until the electrolytic solution was exhausted, were used.

Further, in the melting and separating device installed in the furnace, as the cylindrical container (reference numeral 11 in FIG. 1), an austenitic SUS304 can, a tin can, and a SUS304 bat were used. Further, as the partition plate (reference numeral 12 in FIG. 1) for dividing the inside of the cylindrical container into the upper part and the lower part, an austenitic SUS304 plate with a thickness of 0.6 mm and the surface of the SUS304 plate are used. The one in which striped protrusions were processed and formed was used. In the striped plate-like processing, a convex portion was formed from the back side using a punch.
(Melting separation device (container))
Cylindrical can made of SUS304: upper part 225 mmφ x lower part 185 mmφ x height 296 mm
Tin can: Upper 235 mmφ x lower 235 mmφ x height 340 mm
SUS304 bat: upper 253 mmφ x lower 194 mmφ x height 42 mm

Further, the partition plate of the melting separation device was provided in the container so as to be inclined in a predetermined direction, and an opening (reference numeral 12 in FIG. 1) was formed at the lowest portion in the height direction of the inclination. The "minimum opening width" in Table 1 is the minimum width of the opening.

As the SUS net used in Comparative Example 1, a commercially available stainless steel net made of SUS304 having a mesh opening of 16 mm was used. Further, in Comparative Example 2, the test was conducted without using a partition plate or the like in the container, and the waste battery was directly put into the container can. The minimum opening width in Table 1 in Comparative Example 2 is the width of the upper opening of the SUS304 bat.

≪Results and evaluation≫
The separability of aluminum is determined by the degree of separation between the electrode body and the molten aluminum by heating using the melting separation device, the falling of the fragments of the electrode body to the lower part of the melting separation device, and the recoverability of the fragments. It was evaluated on a three-point scale of "good", "bad", and "impossible". Table 1 below summarizes the test conditions and evaluation results.

As shown in the results of Table 1, in Examples 1 to 4, the aluminum constituting the outer can and the electrode body could be well separated. Specifically, the electrode body remained cleanly on the partition plate in the melting separation device, and the aluminum melted by heating solidified in a lump under the partition plate.

On the other hand, in Comparative Example 1, a part of the electrode body debris that had fallen from the net was bonded to the aluminum melted by heating, and the separability was poor. Further, in Comparative Example 2, there was a portion where the molten luminium and the electrode body were bonded, and separation was impossible.

The SUS cans used in Examples 1, 3 and 5 seemed to have good heat resistance, and it was speculated that they could withstand multiple uses. On the other hand, in the tin cans used in Examples 2, 4 and 6, oxidation was confirmed on a part of the tin can surface after aluminum separation. In addition, since semi-finished products and roasted products that do not contain electrolyte are used as waste batteries, there are no ignitions or explosions, temperature control is easy, and there are problems such as the lid of the furnace flying and the inside of the furnace being damaged. No outbreak was seen.

1, 2, 3, 4, 5 Melting separation device 11 Container 12 Partition plate 12s, 12s'Inclined surface 12h Opening 12f Leg

Claims (7)

A waste lithium-ion battery containing aluminum is placed on the partition plate using a melting separation device that is divided into an upper part and a lower part by a partition plate that is inclined in a predetermined direction and has an inclined surface in which protrusions are formed in a striped pattern . Place and
The aluminum of the waste lithium ion battery is melted by heating so that the temperature inside the melting separation device is in the range of 700 ° C. or higher and 900 ° C. or lower.
A method for separating aluminum from a waste lithium ion battery that separates the molten aluminum by flowing it out from an opening formed at the lowest portion of the inclined surface of the partition plate and collecting it in the lower part of the melting separation device. .. The waste lithium ion according to claim 1, wherein the waste lithium ion battery is detoxified and roasted in advance, and the waste lithium ion battery after the detoxification roasting treatment is placed on a partition plate of the melting separation device. How to separate aluminum from batteries. It is a method of recovering valuable resources from waste lithium-ion batteries.
A method for recovering valuable resources from a waste lithium ion battery, which comprises an aluminum separation step for carrying out the method according to claim 1. A container with a lid and
A partition plate provided inside the container and dividing the container into an upper part and a lower part is provided.
The partition plate has an inclined surface inclined in a predetermined direction, a protrusion is formed in a striped shape on the inclined surface, and an opening is formed at the lowest portion of the inclined surface.
A substance containing a component to be melt-separated is placed on the partition plate, and the substance is placed on the partition plate.
The inside of the container is heated to a temperature at which the component to be melt-separated can be melted, and the component melted by heating flows out from the opening formed on the inclined surface of the partition plate to flow out of the container. Melting separation device collected at the bottom. The melt-separation apparatus according to claim 4, wherein the aluminum contained in the waste lithium ion battery is melt-separated. The melt separation device according to claim 4 or 5, wherein the opening is smaller than the minimum width of the substance placed on the partition plate. The melting separation device according to any one of claims 4 to 6, wherein the lower portion of the container is formed of a dish-shaped body.

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