阅读说明：本技术 一种退役电池正极极片剥离和浸出的方法与装置 (Method and device for stripping and leaching out anode piece of retired battery ) 是由 张海涛 曹相斌 王道广 申长洁 马立彬 邢盛洲 刘艳侠 于 2021-07-09 设计创作，主要内容包括：本发明提供了一种退役电池正极极片剥离和浸出的方法与装置,该方法将拆解后的退役电池正极极片置于剥离釜中,加入双氧水溶液在搅拌和超声条件下使极片上的黏结剂分解从而实现正极极片上活性物质与铝箔的脱离,之后活性物质透过剥离釜内设置的网篮和剥离釜底部出口设置的二次滤网后进入浸出釜中,铝箔被网篮和二次滤网截留从而实现活性物质与铝箔的完全分离。之后向浸出釜中加入无机酸并补充双氧水,在加热和搅拌条件下将活性物质进行溶解浸出,得到的浸出液送往下一步工序除杂后制备电池前驱体材料。本发明的方法在实现活性物质与铝箔的高效分离,简化了工艺步骤,设备系统集成度高,工艺能耗较低,便于实现大规模锂电池回收。(The invention provides a method and a device for stripping and leaching a retired battery positive pole piece, the method comprises the steps of placing the disassembled retired battery positive pole piece into a stripping kettle, adding hydrogen peroxide solution to decompose an adhesive on the pole piece under stirring and ultrasonic conditions so as to separate an active substance on the positive pole piece from an aluminum foil, enabling the active substance to penetrate through a mesh basket arranged in the stripping kettle and a secondary filter screen arranged at an outlet at the bottom of the stripping kettle and then enter into a leaching kettle, and intercepting the aluminum foil by the mesh basket and the secondary filter screen so as to realize complete separation of the active substance and the aluminum foil. And then adding inorganic acid into the leaching kettle, supplementing hydrogen peroxide, dissolving and leaching active substances under the conditions of heating and stirring, and conveying the obtained leachate to the next step for removing impurities to prepare a battery precursor material. The method provided by the invention realizes efficient separation of the active substances and the aluminum foil, simplifies the process steps, has high integration level of equipment and systems and lower process energy consumption, and is convenient for realizing large-scale lithium battery recovery.)

1. The utility model provides a device that retired battery positive pole piece is peeled off and is leached which characterized in that: including peeling off cauldron (1) and leaching cauldron (2), peeling off cauldron (1) and leaching cauldron (2) link to each other through material transmission pipeline (8), it peels off stirring rake (4), basket (5) and ultrasonic transducer (3) to be equipped with in cauldron (1) to peel off, it leaches stirring rake (9) to be equipped with in cauldron (2) to leach.

2. The apparatus of claim 1, wherein: the bottom ends of the peeling stirring paddle (4) and the ultrasonic probe (3) are arranged in the basket (5), and the peeling stirring paddle (4) is connected with the variable-frequency speed regulation device I (15).

3. The apparatus of claim 1, wherein: an electric lifting device (14) is arranged on the stripping kettle (1), the top of the stripping kettle is connected with a stripping kettle support (13) through a hydraulic rod by the electric lifting device (14), and the top of the stripping kettle is controlled to move up, down, left and right by the electric lifting device (14).

4. The apparatus of claim 1, wherein: the leaching kettle (2) is also provided with an acid supply electromagnetic valve (17), a hydrogen peroxide supply electromagnetic valve (18) and a material supplementing port (6), a pH meter (7) is arranged in the leaching kettle (2), and the outer wall of the leaching kettle (2) is provided with an electric heating sleeve (10).

5. The apparatus of claim 1, wherein: the leaching stirring paddle (9) is connected with a variable frequency speed regulating device II (16).

6. The apparatus of claim 1, wherein: the included angle between the material conveying pipeline (8) and the horizontal plane is 15-75 degrees, and the mesh number of the screen mesh adopted by the mesh basket (5) is 5-50 meshes.

7. A method for stripping and leaching a positive pole piece of an ex-service battery is characterized in that the stripping and leaching are carried out by using the device of any one of claims 1 to 6, and specifically comprises the following steps: the method comprises the steps of pre-soaking the waste positive pole piece of the retired electrode in a hydrogen peroxide solution, then stirring and ultrasonically soaking to separate active substances on the positive pole piece from an aluminum foil, adding inorganic acid into obtained stripping slurry, and supplementing hydrogen peroxide to realize effective leaching of the active substances.

8. The method of claim 7, characterized by the steps of:

a. placing the disassembled positive pole piece in a mesh basket (5) for stripping, adding hydrogen peroxide solution into a stripping kettle (1) for presoaking, and then opening a stirring device and an ultrasonic device for intensive soaking;

b. after stripping, lifting the mesh basket (5) to the top of the stripping kettle (1), and recovering the aluminum foil current collector; then, opening a valve at the bottom of the stripping kettle (1), and feeding the materials into the leaching kettle (2) through a material conveying pipeline (8);

c. opening an acid supply electromagnetic valve (17) and a hydrogen peroxide supply electromagnetic valve (18) to adjust the concentration of the inorganic acid and the hydrogen peroxide in the leaching kettle (2), heating, stirring and leaching, filtering and collecting the leaching solution after the stirring is finished.

9. The method of claim 8, wherein: in the step a, the content of hydrogen peroxide in the hydrogen peroxide solution is 1-10%, the pre-soaking time is 0.5-2h, the pre-soaking temperature is 20-30 ℃, the stirring speed in the enhanced soaking stage is 50-500 r/min, the stirring time is 5-60min, and the power of an ultrasonic probe is 50-500W; the temperature of the leaching kettle (2) in the step c is 40-80 ℃, the stirring speed is 100-; in the step c, the concentration of the inorganic acid is 0.5-3M, and the concentration of the hydrogen peroxide is 1-6%.

10. The method of claim 8, wherein: in the leachate obtained in the step c, when the positive electrode active substance is a ternary battery material, the concentration of each metal ion in the leachate is as follows: the lithium ion content is 3-20g/L, the nickel ion content is 5-50g/L, the cobalt ion content is 5-50g/L, and the manganese ion content is 5-50 g/L; when the positive electrode active substance is a lithium iron phosphate material, the concentration of each metal ion in the leaching solution is as follows: the lithium ion content is 2-25g/L, the iron ion content is 5-50g/L, and the phosphate ion content is 10-70 g/L.

Technical Field

The invention relates to the field of lithium ion battery material recovery, in particular to a method and a device for stripping and leaching a pole piece of a retired battery positive pole.

Background

In recent years, with the increasing demand of human beings for new energy automobiles and portable devices, electrochemical energy storage has been widely used worldwide. According to the prediction, the permeability of the new energy automobile reaches 25% in 2025, the yield reaches 250 thousands of automobiles, and the market value breaks through trillion yuan. However, as the heart of a new energy automobile, the power lithium battery contains a plurality of metal elements and organic substances, and serious resource waste and environmental pollution are caused if the power lithium battery is not effectively treated after being retired. Based on this, a series of policy specifications are provided in China to guide the healthy development of the lithium battery recycling industry, and relevant research and industrialization promotion are highly regarded.

At present, the recovery of waste lithium batteries mainly adopts a hydrometallurgy process, namely, the active materials of the batteries are dissolved and leached by utilizing inorganic strong acid and the like, and then valuable elements are separated, recovered and the like by adopting methods of extraction, precipitation and the like. In any process, the splitting of the lithium battery is the first link which cannot be avoided in the recovery process. In the prior art, a heat treatment method, a solvent method, an alkali dissolution method and the like are generally adopted to separate a positive electrode material and an aluminum foil current collector. The invention patent CN101217206A realizes the stripping of the current collector by carrying out heat treatment on the crushed battery core, but the method needs to be carried out at high temperature, the energy consumption is high, and the organic solvent remained in the electrode can generate harmful gas in the treatment process. In the invention patent CN101212074A, an organic solvent is used to soak the positive plate to separate the aluminum foil from the positive material, but the organic solvent (such as N, N-dimethylformamide) has slight toxicity and high cost. In patent CN 101599563B, an alkaline solution is used to dissolve an aluminum foil to separate an anode material, however, in the method, a large amount of waste liquid is generated due to the use of a strong base, which increases the difficulty of post-treatment, and a plurality of steps are required to recover aluminum in an alkaline leaching filtrate. Therefore, green continuous operation is realized on stripping and subsequent treatments of active substance leaching, impurity removal and the like, material recycling system engineering is introduced to reduce energy consumption, and the method has important significance on large-scale treatment of waste lithium batteries.

Disclosure of Invention

The invention provides a method and a device for stripping and leaching a retired battery positive pole piece. The method disclosed by the invention has the advantages of no secondary pollutant in the operation process, realization of effective utilization of hydrogen peroxide, high integration level, simple flow, low energy consumption and the like.

The technical scheme for realizing the invention is as follows:

the utility model provides a device that retired battery positive pole piece peeled off and leached, is including peeling off the cauldron and leaching the cauldron, peel off the cauldron and leach the cauldron and pass through material transmission pipeline and link to each other, peel off and be equipped with in the cauldron and peel off stirring rake, basket and ultrasonic transducer, be equipped with in the leaching cauldron and leach the stirring rake.

The bottom ends of the peeling stirring paddle and the ultrasonic probe are arranged in the basket, and the peeling stirring paddle is connected with the variable-frequency speed regulation device I.

The stripping kettle is provided with an electric lifting device, the electric lifting device is used for stripping the top of the stripping kettle and connecting with a stripping kettle support through a hydraulic rod, and the electric lifting device can be used for controlling the stripping kettle to move up and down and left and right, so that the stripping kettle can be separated from the bottom of the stripping kettle.

The leaching kettle is also provided with an acid supply electromagnetic valve, a hydrogen peroxide supply electromagnetic valve and a material supplementing port, a pH meter is arranged in the leaching kettle, and the outer wall of the leaching kettle is provided with an electric heating sleeve.

And the leaching stirring paddle is connected with a variable-frequency speed regulating device II.

The included angle between the material conveying pipeline and the horizontal plane is 15-75 degrees, and the mesh number of the screen mesh adopted by the mesh basket is 5-50 meshes.

A method for stripping and leaching a positive pole piece of a retired battery specifically comprises the following steps: the method comprises the steps of pre-soaking the waste positive pole piece of the retired electrode in a hydrogen peroxide solution, then stirring and ultrasonically soaking to separate active substances on the positive pole piece from an aluminum foil, adding inorganic acid into obtained stripping slurry, and supplementing hydrogen peroxide to realize effective leaching of the active substances.

The method comprises the following specific steps:

a. placing the disassembled positive pole piece in a mesh basket for stripping, adding hydrogen peroxide solution into a stripping kettle for presoaking, and then, carrying out enhanced soaking under stirring and ultrasonic conditions to decompose the adhesive on the pole piece, thereby realizing the separation of active substances on the positive pole piece from the aluminum foil;

b. after stripping, lifting the mesh basket to the top of the stripping kettle, screening the aluminum foil by the mesh basket arranged in the stripping kettle and a secondary filter screen arranged at an outlet at the bottom of the stripping kettle so as to completely separate the active substances from the aluminum foil, and obtaining stripping slurry containing the active substances at the outlet at the bottom of the stripping kettle; opening a valve at the bottom of the stripping kettle, and feeding the materials into the leaching kettle through a material conveying pipeline;

c. opening an acid supply electromagnetic valve and a hydrogen peroxide supply electromagnetic valve to adjust the concentration of inorganic acid and hydrogen peroxide in the leaching kettle, dissolving and leaching active substances under the conditions of heating and stirring, filtering leaching slurry in the leaching kettle after stirring is finished, and collecting a liquid phase to obtain a leaching solution.

In the step a, the content of hydrogen peroxide in the hydrogen peroxide solution is 1-10%, the pre-soaking time is 0.5-2h, the pre-soaking temperature is 20-30 ℃, the stirring speed in the enhanced soaking stage is 50-500 r/min, the stirring time is 5-60min, and the power of an ultrasonic probe is 50-500W; the temperature of the leaching kettle in the step c is 40-80 ℃, the stirring speed is 100-300 r/min, and the stirring time is 0.5-2 h; in the step c, the concentration of the inorganic acid is 0.5-3M, and the concentration of the hydrogen peroxide is 1-6%.

In the leachate obtained in the step c, when the positive electrode active substance is a ternary battery material, the concentration of each metal ion in the leachate is as follows: the lithium ion content is 3-20g/L, the nickel ion content is 5-50g/L, the cobalt ion content is 5-50g/L, and the manganese ion content is 5-50 g/L; when the positive electrode active substance is a lithium iron phosphate material, the concentration of each metal ion in the leaching solution is as follows: the lithium ion content is 2-25g/L, the iron ion content is 5-50g/L, and the phosphate ion content is 10-70 g/L.

The invention has the beneficial effects that:

(1) the green degree of the waste battery recovery process is improved, compared with the traditional process, no toxic and harmful organic solvent is introduced, the decomposition of the adhesive is caused by the fact that the free radicals generated by hydrogen peroxide continuously contact the pole pieces, the separation of the electrode material and the aluminum foil is further accelerated by mechanical stirring, and the separation efficiency can be further improved by the ultrasonic cavitation effect, so that the separation of the aluminum foil and the powder material is directly realized.

(2) The integration level of the device system is improved, and semi-continuous operation of the pole piece stripping process can be realized through the combination of the net basket and the kettle top lifting device; through will peel off and leach the device and establish ties, can realize peeling off and leach the process synchronization and go on, promote work efficiency.

(3) The process energy consumption is reduced, and the recovery treatment cost is saved. Compared with the traditional heat treatment, the method reduces a large amount of energy consumption. In addition, the soaking solution can be circularly soaked and stripped for multiple times in the process, and finally acid and hydrogen peroxide can be supplemented for leaching the active material in the next step, so that the waste liquid treatment cost and the raw material cost are reduced.

(4) The method is suitable for ternary and lithium iron phosphate positive pole pieces, and can provide technical guidance for subsequent large-scale lithium battery power recovery.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a process flow diagram of the present invention.

FIG. 2 is a system diagram of the apparatus of the present invention.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive effort based on the embodiments of the present invention, are within the scope of the present invention.

As shown in fig. 2, the device for stripping and leaching the cathode plate of the retired battery comprises a stripping kettle 1 and a leaching kettle 2, wherein the stripping kettle 1 is fixed by a stripping kettle support 13, and the leaching kettle 2 is fixed by a leaching kettle support 12; the stripping kettle 1 and the leaching kettle 2 are connected through a material conveying pipeline 8, the included angle between the material conveying pipeline 8 and the horizontal plane is 15-75 degrees, a stripping stirring paddle 4, a basket 5 and an ultrasonic probe 3 are arranged in the stripping kettle 1, the basket 5 is fixed on the kettle wall of the stripping kettle through a buckle, and the stripping kettle can be taken out after the top of the kettle is lifted; the ultrasonic probe 3 can realize continuous or intermittent ultrasonic work through control; the leaching kettle is characterized in that a leaching stirring paddle 9 is arranged in the leaching kettle 2, the leaching stirring paddle 9 is connected with a variable frequency speed regulation device II 16, an acid supply electromagnetic valve 17 is further arranged on the leaching kettle 2, a hydrogen peroxide electromagnetic valve 18 and a replenishing port 6 are provided, a pH meter 7 is arranged in the leaching kettle 2, the concentrations of inorganic acid and hydrogen peroxide in the leaching kettle are adjusted by the acid supply electromagnetic valve 17 and the hydrogen peroxide electromagnetic valve 18, an electric heating sleeve 10 is arranged on the outer wall of the leaching kettle 2, active substances are dissolved and leached under heating and stirring conditions, leaching slurry in the leaching kettle flows out from a discharging port 11 after stirring is finished, and a liquid phase is collected after filtering to obtain leaching liquid.

The bottom ends of the peeling stirring paddle 4 and the ultrasonic probe 3 are arranged in the net basket 5, and the peeling stirring paddle 4 is connected with the variable-frequency speed regulation device I15.

The stripping kettle 1 is provided with an electric lifting device 14, the electric lifting device 14 is used for connecting the top of the stripping kettle with a stripping kettle support 13 through a hydraulic rod, and the electric lifting device 14 can be used for controlling the stripping kettle to move up, down, left and right, so that the separation of the top and the bottom of the stripping kettle is realized.

The mesh number of the screen mesh adopted by the basket 5 is 5-50 meshes.

The stripping kettle 1 and the leaching kettle 2 are connected through a material conveying pipeline 8, and the included angle between the material conveying pipeline 8 and the horizontal plane is 45 degrees; after the enrichment of the stripping slurry is completed, the valve in the transmission pipeline 8 is opened, so that the transmission of the stripping slurry to the leaching kettle can be realized.

Example 1

The device is used for stripping and leaching, and specifically comprises the following steps:

and (3) disassembling the retired ternary power battery after complete discharge, placing the obtained positive pole piece in a stripping kettle basket for stripping, soaking at room temperature for 0.5h in advance, wherein the concentration of hydrogen peroxide in a soaking solution is 3%, then opening a stirring device and an ultrasonic device, stirring at a rotating speed of 300r/min, ultrasonic power of 150W, and treatment time of 60min, and carrying out repeated stripping for a plurality of times. Lifting the kettle top after stripping is finished, recovering an aluminum foil current collector from a mesh basket below, opening a bottom valve to enable active powder and a soak solution to flow into the leaching kettle by virtue of gravity, opening a top acid storage tank and a hydrogen peroxide storage tank valve, adjusting the sulfuric acid concentration in the leaching kettle to be 2M, the hydrogen peroxide concentration to be 4%, and controlling the proportion of active substances to liquid to be 1: 8, heating, stirring and leaching the active substances at 80 ℃, wherein the stirring speed is 200r/min, and the stirring time is 50 min; and after stirring is finished, filtering the leaching slurry in the leaching kettle, collecting a liquid phase to obtain a leaching solution, analyzing the composition result to obtain a composition result shown in table 1, then sending the leaching solution to an extraction tank for deep extraction and impurity removal, and finally sending the leaching solution to a coprecipitation reaction kettle to prepare the required precursor.

Table 1 leachate composition content ICP test data

Example 2

The method for stripping and leaching the anode plate of the retired battery comprises the following steps:

the method comprises the steps of completely discharging the decommissioned ternary power battery, then disassembling, placing the obtained positive pole piece in a stripping kettle basket for stripping, pre-soaking the pole piece for 1h at 30 ℃, controlling the concentration of hydrogen peroxide in a soaking solution to be 2%, then simultaneously opening a stirring device and an ultrasonic device, wherein the stirring speed is 400r/min, the ultrasonic power is 200W, the treatment time is 45 min, and thus, the stripping is performed for a plurality of times in a circulating manner. Lifting the kettle top after stripping is finished, recovering an aluminum foil current collector from a mesh basket below, opening a bottom valve to enable active powder and a soak solution to flow into the leaching kettle by virtue of gravity, opening a top acid storage tank and a hydrogen peroxide storage tank valve, adjusting the sulfuric acid concentration in the leaching kettle to be 3M, the hydrogen peroxide concentration to be 5%, and controlling the proportion of active substances to liquid to be 1: 6, heating, stirring and leaching the active substances at 70 ℃, wherein the stirring speed is 200r/min, and the stirring time is 80 min; and after stirring, filtering the leaching slurry in the leaching kettle, collecting a liquid phase to obtain a leaching solution, then sending the leaching solution to an extraction tank for deep extraction and impurity removal, and finally sending the leaching solution to a coprecipitation reaction kettle to prepare the required precursor.

Example 3

The method for stripping and leaching the anode plate of the retired battery comprises the following steps:

the method comprises the steps of completely discharging the retired lithium iron phosphate power battery, then disassembling the retired lithium iron phosphate power battery, placing the obtained positive pole piece in a stripping kettle basket for stripping, pre-soaking the pole piece for 2 hours at room temperature, controlling the concentration of hydrogen peroxide in a soaking solution to be 4%, then simultaneously opening a stirring device and an ultrasonic device, wherein the stirring speed is 350r/min, the ultrasonic power is 200W, and the treatment time is 2 hours. Lifting the kettle top after stripping is finished, recovering an aluminum foil current collector from a net basket below, opening a bottom valve to enable active powder and a soak solution to flow into the leaching kettle by virtue of gravity, opening a top acid storage tank and a hydrogen peroxide storage tank valve, adjusting the concentration of hydrochloric acid in the leaching kettle to be 2M, the concentration of hydrogen peroxide to be 4%, and controlling the proportion of active substances to liquid to be 1: 8, heating, stirring and leaching the active substances at 40 ℃, wherein the stirring speed is 250r/min, and the stirring time is 80 min; and after stirring, filtering the leaching slurry in the leaching kettle, and collecting a liquid phase to obtain a leaching solution. And then adjusting the pH value of the leachate by using soda ash to generate iron phosphate precipitate, and then carrying out the working procedures of recrystallization purification, washing, drying, calcining and the like on the crude iron phosphate to obtain the battery-grade iron phosphate.

Example 4

The method for stripping and leaching the anode plate of the retired battery comprises the following steps:

and (2) disassembling the retired ternary power battery after complete discharge, placing the obtained positive pole piece in a stripping kettle basket for stripping, soaking the pole piece at room temperature for 0.5h, controlling the concentration of hydrogen peroxide in the solution to be 3%, simultaneously opening a stirring device and an ultrasonic device after soaking is finished, stirring at the rotating speed of 400r/min, the ultrasonic power of 300W, and the treatment time of 1h, and thus, circularly stripping for a plurality of times. Lifting the kettle top after stripping is finished, recovering an aluminum foil current collector from a mesh basket below, opening a bottom valve to enable active powder and a soak solution to flow into the leaching kettle by virtue of gravity, opening a top acid storage tank and a hydrogen peroxide storage tank valve, adjusting the sulfuric acid concentration in the leaching kettle to be 2.5M, the hydrogen peroxide concentration to be 4%, and controlling the proportion of active substances to liquid to be 1: 7, heating and stirring the active substances at 60 ℃ for leaching, wherein the stirring speed is 300r/min, and the stirring time is 120 min. And after stirring, filtering the leaching slurry in the leaching kettle, collecting a liquid phase to obtain a leaching solution, then conveying the leaching solution to an extraction tank for deep extraction and impurity removal, and then conveying the leaching solution to a coprecipitation reaction kettle to prepare the required precursor.

Example 5

The method for stripping and leaching the anode plate of the retired battery comprises the following steps:

the method comprises the steps of completely discharging the retired lithium iron phosphate power battery, then disassembling, placing the obtained positive pole piece in a stripping kettle basket for stripping, pre-soaking the pole piece for 1 hour at room temperature, controlling the concentration of hydrogen peroxide in a soaking solution to be 3%, then simultaneously opening a stirring device and an ultrasonic device, wherein the stirring speed is 350r/min, the ultrasonic power is 300W, the treatment time is 90 min, and thus, the steps are circularly stripped for several times. Lifting the kettle top after stripping is finished, recovering an aluminum foil current collector from a net basket below, opening a bottom valve to enable active powder and a soak solution to flow into the leaching kettle by virtue of gravity, opening a top acid storage tank and a hydrogen peroxide storage tank valve, adjusting the concentration of hydrochloric acid in the leaching kettle to be 3M, the concentration of hydrogen peroxide to be 4%, and controlling the proportion of active substances to liquid to be 1: 6, heating and stirring the active substances at 45 ℃ for leaching, wherein the stirring speed is 300r/min, and the stirring time is 60 min. And after stirring, filtering the leaching slurry in the leaching kettle, collecting a liquid phase to obtain a leaching solution, and then conveying the leaching solution to the next step to prepare the battery-grade iron phosphate.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.