Device and method for recovering metal ions in waste lithium ion battery

Abstract

The invention discloses a device for recovering metal ions in waste lithium ion batteries. Comprising a discharge storage tank, a crushing tank, a screening tank, a drying box, an organic matter removal tank, an alkali liquor tank and an adsorption and desorption tank, a conveyor belt is arranged between a bottom outlet of the discharge storage tank and a top inlet of the crushing tank; a conveying belt is arranged between a bottom outlet of the crushing tank and a top inlet of the screening groove; a metal shell recovery outlet and an electrode material outlet are formed in the bottom of the screening tank; the electrode material outlet is connected with the drying box, a conveying belt is arranged between a bottom outlet of the drying box and a top inlet of the organic matter removal tank, a conveying belt is arranged between a bottom outlet of the organic matter removal tank and a top inlet of the alkali liquor tank, and a liquid outlet of the alkali liquor tank is connected with the bottom of the adsorption and desorption tank. According to the method, metal ions can be effectively recycled from raw material discharging to final lithium ion recycling, and resource utilization of waste batteries is achieved.

Description

Technical Field

[0001] The invention belongs to the field of battery recycling, and in particular relates to a device and method for recycling metal ions in lithium-ion batteries. Background Art

[0002] In the past two decades, the market for lithium-ion batteries (LIBs) has grown significantly and has been widely used in 3C, electric vehicles, energy storage and other fields. However, after reaching the end of their service life, a large number of retired lithium-ion batteries will be generated, which contain a large number of valuable metal elements and harmful substances. If improperly handled, it will cause waste of resources and cause environmental pollution and safety problems. Therefore, the recovery and recycling technology of retired lithium-ion batteries has become a hot topic in current research and has also attracted global attention.

[0003] Existing lithium-ion battery electrode materials generally use lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate and ternary materials. Retired ternary lithium-ion batteries contain abundant valuable metal elements such as lithium, nickel and cobalt, of which Co accounts for 5% to 20%, Ni accounts for 5% to 12%, Mn accounts for 7% to 10%, and Li accounts for 2% to 5%. The potential resource volume is huge and the economic value of recycling is high.

[0004] In the prior art, there are few disclosures on the recovery devices for metals in waste lithium-ion batteries, and the structures are relatively complex. The present invention provides a complete set of recovery devices, from the discharge of raw materials to the final lithium ion recovery, which can effectively recover metal ions and realize the resource utilization of waste batteries. Summary of the invention

[0005] The present invention overcomes the defects of the prior art and provides a device and method for recovering metal ions from waste lithium-ion batteries.

[0006] The technical solution of the present invention is as follows.

[0007] A device for recovering metal ions from waste lithium-ion batteries comprises a discharge storage tank, a crushing tank, a screening tank, a drying box, an organic matter removal tank, an alkali liquid tank, a pH adjustment tank and an adsorption and desorption tank; a conveyor belt is arranged between the bottom outlet of the discharge storage tank and the top inlet of the crushing tank; a conveyor belt is arranged between the bottom outlet of the crushing tank and the top inlet of the screening tank; a metal shell recovery outlet and an electrode material outlet are arranged at the bottom of the screening tank; the electrode material outlet is connected to the drying box, a conveyor belt is arranged between the bottom outlet of the drying box and the top inlet of the organic matter removal tank, a conveyor belt is arranged between the bottom outlet of the organic matter removal tank and the top inlet of the alkali liquid tank, the liquid outlet of the alkali liquid tank is connected to the pH adjustment tank, and the bottom outlet of the pH adjustment tank is connected to the bottom of the adsorption and desorption tank.

[0008] Furthermore, the screening trough consists of a screening trough body, a vibrating conveyor belt, a fan, and a collecting trough; a fan is arranged on one side of the screening trough body, and more than one vibrating conveyor belt is arranged in the screening trough body, and a Z-shaped structure is formed between the vibrating conveyor belts; a collecting trough for collecting electrode powder is arranged at the bottom of the side opposite to the fan inside the screening trough body, and the outlet of the collecting trough is the electrode material outlet, and a metal shell outlet is arranged below the vibrating conveyor belt. The screening trough mainly utilizes the different densities of the battery shell material and the motor material, and adopts the fan airflow for screening, and the screened motor material enters the electrode powder collection trough, and other substances enter the metal shell outlet through the vibrating conveyor belt.

[0009] Furthermore, the adsorption and desorption tank has a liquid outlet and a liquid inlet at the top and bottom respectively.

[0010] Furthermore, the adsorption and desorption tank is provided with a placement rack, an adsorbent placement container, a spoiler, a placement rack and an adsorbent placement container from bottom to top; the adsorbent placement container is placed on the placement rack; the adsorbent placement container is a columnar structure made of a mesh material and is filled with a lithium adsorbent.

[0011] Furthermore, an ultrasonic column is arranged on the placement rack, and an adsorbent placement container channel is correspondingly arranged on the adsorbent placement container. When the adsorbent placement container is placed on the placement rack, the adsorbent placement container channel is just inserted into the ultrasonic column.

[0012] Furthermore, the bottoms of the discharge storage tank, the crushing tank, the organic matter removal tank and the alkali solution tank are all provided with liquid outflow outlets, and valves are provided on the liquid outflow outlet pipes.

[0013] A method for recovering metal ions from waste lithium-ion batteries using the device comprises the following steps: (1) Place the discarded batteries in an electrical storage tank, add a saturated KCl solution to the electrical storage tank 1, and perform a discharge operation; then, after the liquid is discharged, open the bottom outlet so that the discharged batteries enter the crushing tank through a conveyor belt; the discharge operation time is 12 to 24 hours; (2) In the crushing tank, after the crushing equipment crushes the battery and discharges the liquid, the bottom outlet is opened, so that the crushed battery enters the screening tank through the conveyor belt for screening, wherein the metal shell is screened out through the metal shell outlet for recycling; the electrode powder is screened out through the electrode material outlet and then enters the drying box for drying, wherein the drying box performs low-temperature drying and removal of the electrolyte; (3) The dried electrode material enters the organic matter removal tank through a conveyor belt, and the organic matter removal tank is a pyrolysis device; after the electrode material is pyrolyzed in the organic matter removal tank to remove organic matter, the bottom outlet is opened to allow the electrode material to enter the alkali solution tank through the conveyor belt; (4) The alkali liquid tank 7 is filled with sodium hydroxide solution. After soaking for 12 to 20 hours, the soaking liquid enters the pH adjustment tank, and an acidic solution is added to form a suspension with a pH of 6 to 7. The suspension enters the adsorption and desorption tank 8 to recover the metal. After recovery, pure water is used to desorb the inside of the adsorption and desorption tank 8. The ultrasonic power in the adsorption and desorption tank 8 is 20 to 90 kHz. The metal ions are lithium ions.

[0014] In the above method, in step (2), the drying temperature is 200-300°C.

[0015] In the above method, in step (3), the pyrolysis is: heating the electrode material at 300-500°C for 3-6h.

[0016] In the above method, in step (4), the recovered metal is the recovery of lithium ions.

[0017] Compared with the prior art, the advantages of the present invention are: The present invention starts with the recycling of waste lithium-ion batteries and provides a complete set of metal ion recovery devices, which can realize the whole process from discharge to metal ion recovery, reduce the steps of manual operation, and have a simple structure and are easy to implement. In addition, the present invention can efficiently recover lithium ions. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a flow chart of a method for recovering metal ions from waste lithium-ion batteries of the present invention; Figure 2 This is a schematic diagram of a device for recovering metal ions from waste lithium-ion batteries according to the present invention; Figure 3 Schematic diagram of the internal structure of the screening tank; Figure 4 Schematic diagram of the external structure of the screening tank; Figure 5 This is a schematic diagram of the interior of the screening tank from a top-down perspective; Figure 6 It is a schematic diagram of the internal structure of the adsorption and desorption tank; Figure 7 a cross-sectional view of a container for placing adsorbent; Figure 8 It is a structural schematic diagram of the ultrasonic column; Fig. 9 It is a schematic diagram of the structure of the placement rack and the ultrasonic column; Fig.10A schematic diagram showing a container for placing adsorbent from an upward angle; Fig.11 is a cross-sectional view of the spoiler; Fig.12 A top view of the spoiler.

[0020] The components in the figure are as follows: discharge storage tank 1, crushing tank 2, conveyor belt 3, screening tank 4, vibration conveyor belt 4.1, fan 4.2, collecting tank 4.3, drying box 5, organic matter removal tank 6, alkali liquid tank 7, adsorption and desorption tank 8, adsorbent placement container 8.1, adsorbent placement container channel 8.2, ultrasonic column 8.3, placement rack 8.4, spoiler 8.5, liquid outflow outlet 9, pH adjustment tank 10. DETAILED DESCRIPTION

[0021] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0022] Example 1 like Figure 2 As shown, a metal ion recovery device in waste lithium-ion batteries comprises a discharge storage tank 1, a crushing tank 2, a screening tank 4, a drying box 5, an organic matter removal tank 6, an alkali liquid tank 7, a pH adjustment tank 10 and an adsorption desorption tank 8; a conveyor belt 3 is arranged between the bottom outlet of the discharge storage tank 1 and the top inlet of the crushing tank 2; a conveyor belt 3 is arranged between the bottom outlet of the crushing tank 2 and the top inlet of the screening tank 4; a metal shell recovery outlet and an electrode material outlet are arranged at the bottom of the screening tank 4; the electrode material outlet is connected to the drying box 5, a conveyor belt 3 is arranged between the bottom outlet of the drying box 5 and the top inlet of the organic matter removal tank 6, a conveyor belt 3 is arranged between the bottom outlet of the organic matter removal tank 6 and the top inlet of the alkali liquid tank 7, the liquid outlet of the alkali liquid tank 7 is connected to the pH adjustment tank 10, and the bottom outlet of the pH adjustment tank 10 is connected to the bottom of the adsorption desorption tank 8. The bottoms of the discharge storage tank 1, the crushing tank 2, the organic matter removal tank 6 and the alkali liquid tank 7 are all provided with liquid outflow outlets 9, and valves are provided on the pipelines of the liquid outflow outlets 9.

[0023] In this embodiment, the liquid inlet at the bottom of the adsorption and desorption tank 8 is connected to the pH adjustment tank 10 and the external desorption liquid, such as Figure 2 As shown, valve A and valve B respectively control the entry of two liquids.

[0024] like Figure 3~Figure 5As shown, in this embodiment, the screening trough 4 is composed of a screening trough body, a vibrating conveyor belt 4.1, a fan 4.2, and a collecting trough 4.3; a fan 4.2 is arranged on one side of the screening trough body, and more than one vibrating conveyor belt 4.1 is arranged in the screening trough body, and a Z-shaped structure is formed between the vibrating conveyor belts 4.1; a collecting trough 4.3 for collecting electrode powder is arranged at the bottom of the side opposite to the fan 4.2 inside the screening trough body, and one end of the collecting trough 4.3 is inclined downward in this embodiment, and the outlet of the collecting trough 4.3 is an electrode material outlet, and a metal shell outlet is arranged below the vibrating conveyor belt 4.1.

[0025] like Figure 6 As shown, in this embodiment, the upper and lower parts of the adsorption-desorption tank 8 are respectively provided with a liquid outlet and a liquid inlet. From bottom to top, the adsorption-desorption tank 8 is provided with a placement rack 8.4, an adsorbent placement container 8.1, a spoiler 8.5, a placement rack 8.4 and an adsorbent placement container 8.1; the adsorbent placement container 8.1 is placed on the placement rack 8.4; the adsorbent placement container 8.1 is a columnar structure made of a mesh material, and is filled with a lithium adsorbent. The mesh material allows the external solution to enter the adsorbent placement container to contact and adsorb lithium ions. Figure 8 and Fig. 9 As shown, an ultrasonic column 8.3 is arranged on the placement rack 8.4, and an adsorbent placement container channel 8.2 is correspondingly arranged on the adsorbent placement container 8.1. When the adsorbent placement container 8.1 is placed on the placement rack 8.4, the adsorbent placement container channel 8.2 is just inserted into the ultrasonic column 8.3.

[0026] The spoiler disc 8.5 in this embodiment is as follows Fig.11 and Fig.12 As shown, a plurality of strip-shaped spoiler columns are arranged in the spoiler plate body, and the passing liquid forms turbulence in the spoiler columns.

[0027] Example 2 The preparation method of the adsorbent in the adsorbent placement container in the above-mentioned Example 1 is as follows: (1) 5 kg of coal fly ash, 20 kg of kaolin, 7 kg of attapulgite and 8 kg of starch were mixed, the materials were mixed with 25 kg of water, ground, centrifuged, the precipitate was taken, extruded into a spherical state, and then calcined at 5 ° C for 3 hours to obtain a treated filler carrier; (2) First, take 100g of boric acid and 100g of sodium hexametaphosphate, add them to 100L of water to prepare a mixed solution of boric acid and sodium hexametaphosphate; take 1500g of AlCl3 and 700g of NaAlO2 and dissolve them in the mixed solution of boric acid and sodium hexametaphosphate (50L each), add 15kg of filler carrier to the mixed solution of AlCl3, let it stand for 5h, and then place the solution in a water bath, and control the water bath temperature to 55℃; add the NaAlO2 mixed solution and 50L of LiCl solution (15g / L), and then slowly add ammonia solution to control the pH value to 4~5; (3) Centrifuge at 150 r / min for 20 min and dry the precipitate; (4) The mixture was eluted in deionized water for 5 h to obtain an adsorbent.

[0028] Example 3 This embodiment adopts the device in Example 1 and the adsorbent in Example 2.

[0029] (1) Place the discarded batteries in an electrical storage tank 1, add a saturated KCl solution to the electrical storage tank 1, and soak the batteries in the saturated KCl solution for 12 hours; then, after the liquid is discharged, open the bottom outlet, so that the discharged batteries enter the crushing tank 2 through the conveyor belt 3; (2) In the crushing tank 2, after the crushing equipment crushes the battery and discharges the liquid, the bottom outlet is opened, so that the crushed battery enters the screening tank 4 through the conveyor belt 3 for screening, wherein the metal shell is screened out through the metal shell outlet for recovery; the electrode powder is screened out through the electrode material outlet and then enters the drying box 5 for drying at 200°C, wherein the drying box 5 performs low-temperature drying and removal of the electrolyte; (3) The dried electrode material passes through the conveyor belt 3 and enters the organic matter removal tank 6, which is a pyrolysis device; the electrode material is heated at 500° C. for 3 h in the organic matter removal tank 6 to remove organic matter, and then the bottom outlet is opened to allow the electrode material to pass through the conveyor belt 3 and enter the alkali solution tank 7; (4) The alkali liquid tank 7 is filled with sodium hydroxide solution. After soaking for 12 hours, it enters the pH adjustment tank 10, and hydrochloric acid solution is added to form a suspension with a pH of 6-7. At this time, valve A is opened and valve B is closed. The suspension enters the adsorption and desorption tank 8 to recover lithium ions. The ultrasonic power in the adsorption and desorption tank 8 is 20kHz. After recovery, valve A is closed, valve B is opened, and pure water is used to desorb the inside of the adsorption and desorption tank 8. The recovered desorption liquid is collected to achieve lithium ion recovery.

[0030] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the scope of protection of the invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on these embodiments, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in this field can still combine, add, delete or make other adjustments to the features in the various embodiments of the present invention according to the circumstances without conflict, without making creative work, so as to obtain different other technical solutions that do not deviate from the concept of the present invention in essence, and these technical solutions also belong to the scope of protection of the present invention.

Claims

1. A device for recovering metal ions from waste lithium-ion batteries, characterized in that: The invention comprises a discharge storage tank (1), a crushing tank (2), a screening tank (4), a drying box (5), an organic matter removal tank (6), an alkali liquid tank (7), a pH adjustment tank (10) and an adsorption desorption tank (8); a conveyor belt (3) is arranged between the bottom outlet of the discharge storage tank (1) and the top inlet of the crushing tank (2); a conveyor belt (3) is arranged between the bottom outlet of the crushing tank (2) and the top inlet of the screening tank (4); a metal shell recovery outlet and an electrode material outlet are arranged at the bottom of the screening tank (4); the electrode material outlet is connected to the drying box (5); a conveyor belt (3) is arranged between the bottom outlet of the drying box (5) and the top inlet of the organic matter removal tank (6); a conveyor belt (3) is arranged between the bottom outlet of the organic matter removal tank (6) and the top inlet of the alkali liquid tank (7); the liquid outlet of the alkali liquid tank (7) is connected to the pH adjustment tank (10); and the bottom outlet of the pH adjustment tank (10) is connected to the bottom of the adsorption desorption tank (8).

2. The device for recovering metal ions from waste lithium-ion batteries according to claim 1, characterized in that: The screening trough (4) is composed of a screening trough body, a vibrating conveyor belt (4.1), a fan (4.2), and a collecting trough (4.3); a fan (4.2) is arranged on one side of the screening trough body, and more than one vibrating conveyor belt (4.1) is arranged in the screening trough body, and a Z-shaped structure is formed between the vibrating conveyor belts (4.1); a collecting trough (4.3) for collecting electrode powder is arranged at the bottom of the side opposite to the fan (4.2) inside the screening trough body, and the outlet of the collecting trough (4.3) is an electrode material outlet, and a metal shell outlet is arranged below the vibrating conveyor belt (4.1).

3. The device for recovering metal ions from waste lithium-ion batteries according to claim 1, characterized in that: The adsorption and desorption tank (8) has a liquid outlet and a liquid inlet at the top and bottom, respectively.

4. The device for recovering metal ions from waste lithium-ion batteries according to claim 1, characterized in that: The adsorption-desorption tank (8) is provided with a placement rack (8.4), an adsorbent placement container (8.1), a spoiler (8.5), a placement rack (8.4) and an adsorbent placement container (8.1) from bottom to top; the adsorbent placement container (8.1) is placed on the placement rack (8.4); the adsorbent placement container (8.1) is a columnar structure made of a mesh material and is filled with a lithium adsorbent.

5. The device for recovering metal ions from waste lithium-ion batteries according to claim 4, characterized in that: The placement rack (8.4) is provided with an ultrasonic column (8.3), and the adsorbent placement container (8.1) is correspondingly provided with an adsorbent placement container channel (8.2); when the adsorbent placement container (8.1) is placed on the placement rack (8.4), the adsorbent placement container channel (8.2) fits exactly into the ultrasonic column (8.3).

6. The device for recovering metal ions from waste lithium-ion batteries according to claim 1, characterized in that: The bottoms of the discharge storage tank (1), the crushing tank (2), the organic matter removal tank (6) and the alkali liquid tank (7) are all provided with liquid outflow outlets (9), and valves are provided on the pipelines of the liquid outflow outlets (9).

7. A method for recovering metal ions from waste lithium-ion batteries using the device according to any one of claims 1 to 6, characterized in that: The steps include: (1) placing discarded batteries in an electrical storage tank (1), adding a saturated KCl solution to the electrical storage tank (1), and performing a discharge operation; then, after the liquid is discharged, opening the bottom outlet, allowing the discharged batteries to enter a crushing tank (2) through a conveyor belt (3); the discharge operation time is 12 to 24 hours; (2) In the crushing tank (2), after the crushing equipment crushes the battery and discharges the liquid, the bottom outlet is opened, so that the crushed battery enters the screening tank (4) through the conveyor belt (3) for screening, wherein the metal shell is screened out through the metal shell outlet for recovery; the electrode powder is screened out through the electrode material outlet and then enters the drying box (5) for drying, wherein the drying box (5) is used to dry and remove the electrolyte at low temperature; (3) The dried electrode material passes through a conveyor belt (3) and enters an organic matter removal tank (6), wherein the organic matter removal tank (6) is a pyrolysis device; after the electrode material is heated in the organic matter removal tank (6) to remove organic matter, the bottom outlet is opened, so that the electrode material passes through the conveyor belt (3) and enters an alkali solution tank (7); (4) The alkali liquid tank (7) is filled with sodium hydroxide solution. After soaking for 12 to 20 hours, the soaking liquid enters the pH adjustment tank, and an acid solution is added to form a suspension with a pH of 6 to 7. The suspension enters the adsorption desorption tank (8) to recover the metal. After recovery, pure water is used to desorb the inside of the adsorption desorption tank (8). The ultrasonic power in the adsorption desorption tank (8) is 20 to 90 kHz. The metal ions are lithium ions.

8. The method according to claim 7, characterized in that: In step (2), the drying temperature is 200-300°C.

9. The method according to claim 7, characterized in that: In step (3), the pyrolysis is as follows: the electrode material is heated at 300-500°C for 3-6 hours.

10. The method according to claim 7, characterized in that: In step (4), the recovered metal is recovered lithium ions.

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