Method for separating carbon powder, copper powder and aluminum powder from waste power battery black powder material

Abstract

The application discloses a method for separating carbon powder, copper powder and aluminum powder from waste power battery black powder material, and the steps include rough flotation, cleaning flotation, fine flotation, spiral chute separation, first-stage table separation, second-stage table separation and third-stage table separation. The application first carries out rough flotation on the black powder by preparing a suspension, then carries out fine flotation to separate qualified graphite carbon powder, and then sequentially carries out spiral chute and multi-stage table reselection on the black powder after decarburization by cleaning flotation, so as to finally separate copper foil powder, aluminum foil powder and electrode powder, and the separated carbon powder, copper foil powder and aluminum foil powder all have high grade and recovery rate, and the recycling rate of the waste power battery black powder material is significantly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of waste power battery recycling, and particularly relates to a method for separating carbon powder, copper powder and aluminum powder from waste power battery black powder. BACKGROUND

[0002] At present, new energy vehicles in China mostly use ternary lithium batteries, lithium iron phosphate and the like as power batteries. Due to cyclic charging and discharging, the battery capacity will slowly decay, and it is estimated that a large number of power lithium batteries will enter the retirement period within two or three years. If the retired power batteries cannot be recycled safely and environmentally, it will cause great harm to the environment and society. First, the waste power batteries contain heavy metals such as nickel, cobalt and manganese, and fluorine-containing organic matter such as electrolyte, which pollute the environment. Secondly, since the waste power batteries still contain high voltage, improper operation during recycling, disassembling and processing may cause fire and explosion, heavy metal pollution, organic waste gas emission and other problems. Therefore, it is of great social value to carry out green recycling of retired power batteries, which can not only achieve good economic benefits, but also avoid environmental pollution caused by discarding. Especially, some harmful substances such as hydrofluoric acid are left in the negative electrode material of the waste lithium ion battery, which has great hidden dangers to life and environment. Therefore, it is necessary to recycle the negative electrode material in the waste lithium ion battery to remove these harmful impurities.

[0003] Chinese patent CN106636649A discloses a method for recycling power lithium ion positive electrode material of waste lithium battery. The positive electrode sheet obtained by disassembling is high-temperature treated to remove the binder to obtain the positive electrode material, and then the power lithium ion is obtained by high-speed ball milling and sintering. This method does not recycle and reuse valuable elements such as negative electrode graphite, copper and aluminum, and the recovered positive electrode material is directly sintered without treatment, which has poor electrochemical performance.

[0004] Chinese patent CN101921917A discloses a method for recycling valuable metals from waste lithium battery, and Chinese patent CN107240731A discloses a recycling method of waste power lithium ion battery. The two patent technologies focus on the recycling of lithium element, and other components such as copper and aluminum are not recycled, which causes great resource waste.

[0005] Chinese patent CN112635867A discloses a method for recycling graphite material from waste lithium batteries, which adopts a physical method combining scrubbing-magnetic separation-reselection-pyrolysis-flotation to recycle graphite material. The positive and negative electrode material mixed powder obtained by crushing and sorting the waste power lithium battery is stirred and scrubbed to reduce the adhesion between the negative electrode material and other substances, which is conducive to improving the subsequent high gradient strong magnetic separation sorting effect. The high gradient strong magnetic separation utilizes the difference in specific magnetic susceptibility between the positive electrode material and graphite to separate the positive electrode material and graphite. This scheme mainly recycles graphite, and valuable metals such as copper and aluminum are separated and discharged together in the form of impurities. This scheme does not better recycle valuable metals such as copper and aluminum.

[0006] As can be seen from the above prior art, the existing recycling technology cannot achieve high grade and recovery rate of carbon powder, copper powder and aluminum powder when separating and recycling them from waste power battery black powder material, so a new method for recycling waste power battery black powder material is needed. SUMMARY

[0007] The purpose of the present application is to provide a method for separating carbon powder, copper powder and aluminum powder from waste power battery black powder material, which solves the problem that the prior art cannot separate and recycle high-grade carbon powder, high-grade copper powder and high-grade aluminum powder from waste power battery black powder material.

[0008] To solve the above technical problems, the present application provides a method for separating carbon powder, copper powder and aluminum powder from waste power battery black powder material, characterized in that the steps include:

[0009] Flotation roughing: the original ore with a particle size of -0.6 mm after crushing is subjected to flotation, and after screening, it is divided into flotation roughing tailings and flotation roughing concentrate.

[0010] Flotation scavenging: the flotation roughing tailings are subjected to flotation scavenging, and after screening, they are divided into flotation scavenging tailings and flotation scavenging concentrate.

[0011] Flotation cleaning: the flotation roughing concentrate is subjected to flotation cleaning, and after screening, it is divided into carbon powder material and flotation cleaning tailings. The flotation cleaning tailings and the flotation scavenging concentrate are collected and returned to the flotation roughing step.

[0012] Spiral chute separation: the flotation scavenging tailings are introduced into the spiral chute for washing, and after washing, they are divided into spiral chute tailings and spiral chute concentrate. The spiral chute concentrate is recovered as electrode powder.

[0013] First-stage table separation: the spiral chute tailings are introduced into the table for water washing, and after washing, they are divided into first-stage coarse particle ore, first-stage medium particle ore and first-stage fine particle ore.

[0014] Secondary shaking table sorting: the first-stage medium-granularity ore is introduced into the shaking table for water flow washing, and after washing, the secondary coarse-granularity ore, the secondary medium-granularity ore and the secondary fine-granularity ore are obtained, the secondary medium-granularity ore is returned for the first-stage shaking table sorting step again, and the first-stage fine-granularity ore and the secondary fine-granularity ore are collected as the electrode powder for recovery.

[0015] Tertiary shaking table sorting: the first-stage coarse-granularity ore and the secondary coarse-granularity ore are introduced into the shaking table for water flow washing, and after washing, the tertiary coarse-granularity ore, the tertiary medium-granularity ore and the tertiary fine-granularity ore are obtained, the tertiary coarse-granularity ore is recovered as the copper powder, the tertiary medium-granularity ore is returned for the tertiary shaking table sorting step again, and the tertiary fine-granularity ore is recovered as the aluminum powder.

[0016] The process conditions of the rough flotation step are as follows: the aeration amount is 20-60 ml / min, the pH value is 6-8, the kerosene content is 100-500 g / t, and the flotation time is 1-4 min.

[0017] The process conditions of the rough flotation step are as follows: the aeration amount is 20-60 ml / min, the pH value is 6-8, the kerosene content is 100-500 g / t, and the flotation time is 1-4 min.

[0018] The process conditions of the rough flotation step are as follows: the aeration amount is 20-60 ml / min, the pH value is 6-8, the kerosene content is 100-500 g / t, and the flotation time is 1-4 min.

[0019] The water flow speed in the spiral chute step is 14-16 L / min, the water flow speed in the first-stage shaking table sorting step is 4-6 L / min, the water flow speed in the secondary shaking table sorting step is 7-9 L / min, and the water flow speed in the tertiary shaking table sorting step is 10-13 L / min. The water flow speed in the spiral chute step is set to be the maximum, so as to screen out the electrode powder first. The water flow speeds in the first-stage shaking table sorting step, the secondary shaking table sorting step and the tertiary shaking table sorting step are set to be gradually increased, so as to gradually wash away the impurities and obtain the aluminum powder and the copper powder with high grade.

[0020] Before the rough flotation step, the waste power battery is sequentially disassembled, discharged, washed and dried, first-stage crushed, pyrolyzed and second-stage crushed to obtain the raw ore with a particle size of -0.6 mm.

[0021] The slag after the pyrolysis step contains a metal mixture and an electrode active material, and the slag is cooled and then subjected to secondary crushing to obtain the raw ore.

[0022] The beneficial effects of the present application are that, unlike the prior art, the present application provides a method for separating carbon powder, copper powder and aluminum powder from waste power battery black powder material, which first performs rough flotation by preparing the black powder into a suspension, then performs flotation cleaning to separate qualified graphite carbon powder, and then sequentially performs spiral chute and multi-stage table reselection on the black powder after flotation scavenging and decarbonization, and finally separates copper foil powder, aluminum foil powder and electrode powder, and the separated carbon powder, copper foil powder and aluminum foil powder all have high grade and recovery rate, which significantly improves the recycling rate of waste power battery black powder material. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a flowchart of an embodiment of the method for separating carbon powder, copper powder and aluminum powder from waste power battery black powder material in the present application. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0025] Embodiment 1

[0026] Please refer to Figure 1 The method for separating carbon powder, copper powder and aluminum powder from waste power battery black powder material in the present embodiment has the following steps:

[0027] 1) After the waste power battery is sequentially disassembled, discharged, washed and dried, first crushed, pyrolyzed and secondly crushed, the slag after the pyrolysis step contains a metal mixture and an electrode active material, and the slag is cooled and then subjected to secondary crushing to obtain the raw ore, and the particle size of the raw ore is-0.6 mm.

[0028] 2) Rough flotation: the crushed raw ore with a particle size of-0.6 mm is subjected to flotation, and after screening, it is divided into rough flotation tailings and rough flotation concentrate. In this step, the process conditions for rough flotation are: air charge of 20-60 ml / min, pH value of 6-8, kerosene content of 100-500 g / t, and flotation time of 1-4 min; since the particle size range of the raw ore is wide, the raw ore needs to be preliminarily floated to ensure that the carbon powder material with good quality can be obtained after subsequent flotation cleaning.

[0029] 3) Scavenging flotation: The tailings from the roughing flotation are subjected to scavenging flotation, and after screening, they are separated into scavenging flotation tailings and scavenging flotation concentrate. The process conditions for this scavenging flotation step are: aeration rate of 80 ml / min, pH value of 7, kerosene content of 150 g / t, and flotation time of 5 min.

[0030] 4) Flotation Refinement: The rougher concentrate is further refined by flotation, separating into carbon powder and tailings. The tailings and scavenger concentrate are collected and recirculated for another rougher flotation step. The process conditions for this refinement step are: aeration rate of 100 ml / min, pH value of 7, kerosene content of 50 g / t, and flotation time of 5 min. The recovered carbon powder is analyzed, showing a carbon grade of 89.32% and a carbon recovery rate of 92.17%, indicating high grade and recovery rate.

[0031] 5) Spiral sluice separation: The flotation tailings are fed into a spiral sluice for washing. After washing, the tailings are separated into spiral sluice tailings and spiral sluice concentrate. The spiral sluice concentrate is recovered as electrode powder. In this step, the preferred water flow rate is 15 L / min. In actual experiments, when the washing water flow rate is too low, the slurry cannot be loosened to achieve a stable and effective separation effect; while when the washing water flow rate is too high, more copper and aluminum will be washed into the electrode powder, resulting in a higher copper and aluminum content in the final electrode powder, thus reducing the recovery rate of copper and aluminum powder obtained separately. That is, the change in the washing water flow rate affects the subsequent recovery rate of copper and aluminum powder, so the water flow rate during spiral sluice separation needs to be strictly controlled.

[0032] 6) Primary shaking table separation: The tailings from the spiral chute are introduced into a shaking table for water washing, and after washing, they are separated into primary coarse particles, primary medium particles, and primary fine particles. In this step, the preferred water flow rate is 5 L / min.

[0033] 7) Secondary shaking table separation: The primary medium-particle ore is introduced into a shaking table for water washing. After washing, it is separated into secondary coarse-particle ore, secondary medium-particle ore, and secondary fine-particle ore. The secondary medium-particle ore is recycled back to undergo the primary shaking table separation step again. The primary and secondary fine-particle ore are collected and recovered as electrode powder. In this step, the preferred water flow rate is 8 L / min.

[0034] 8) Third-stage table sorting: the first-stage coarse-grained ore and the second-stage coarse-grained ore are introduced into a table for water flow washing, and after washing, the third-stage coarse-grained ore, the third-stage medium-grained ore and the third-stage fine-grained ore are obtained, the third-stage coarse-grained ore is recovered as copper powder, the third-stage medium-grained ore is recycled for the third-stage table sorting step again, and the third-stage fine-grained ore is recovered as aluminum powder. In this step, the preferred water flow rate is 12 L / min. The component determination of the electrode powder, the copper powder and the aluminum powder obtained in this embodiment is shown in Table 1, and the recovery rate of the copper powder can reach more than 90%, and the recovery rate of the aluminum powder can reach more than 85%, so the carbon powder material, the copper powder and the aluminum powder obtained by recovery have high grade and recovery rate, and the carbon powder material, the copper powder and the aluminum powder obtained by recovery can meet the standard of direct general sale.

[0035] Table 1: Recovery rate and grade of copper powder, aluminum powder and electrode powder in Example 1

[0036]

[0037] Comparative Example 1

[0038] Compared with Example 1, this comparative example does not perform the steps of rough flotation, cleaning flotation and scavenging flotation, but directly performs the subsequent steps of spiral chute sorting and third-stage table sorting, so that the carbon powder material in Example 1 will be mixed into the electrode powder, and the process parameters of the spiral chute sorting and the third-stage table sorting steps remain the same as those in Example 1. Finally, the component determination of the electrode powder, the copper powder and the aluminum powder obtained is shown in Table 2. Compared with Table 1, the grade and recovery rate of the copper powder and the aluminum powder in this comparative example are obviously lower than those in Example 1, which shows that the setting of the steps of rough flotation, cleaning flotation and scavenging flotation before the spiral chute sorting step in Example 1 can significantly improve the grade and recovery rate of the carbon powder material, the copper powder and the aluminum powder.

[0039] Table 2: Recovery rate and grade of copper powder, aluminum powder and electrode powder in Comparative Example 1

[0040]

[0041] Comparative Example 2

[0042] Compared with Example 1, this comparative example does not perform the third-stage table sorting step, but replaces the third-stage table sorting step with the commonly used three-stage spiral chute gravity separation method, and the process conditions of the aforementioned steps of rough flotation, cleaning flotation and scavenging flotation remain the same as those in Example 1, i.e., the obtained carbon powder material is consistent. Finally, the component determination of the copper powder and the aluminum powder obtained is shown in Table 3. Compared with Table 3, the grade and recovery rate of the copper powder and the aluminum powder in this comparative example are lower, which shows that the setting of the third-stage table sorting step after the spiral chute sorting step in Example 1 can significantly improve the grade and recovery rate of the copper powder and the aluminum powder compared with the commonly used three-stage spiral chute gravity separation.

[0043] Table 3 Recovery rate and grade of copper powder, aluminum powder and electrode powder in Comparative Example 2

[0044]

[0045] From the comparison of the above embodiment 1 and comparative examples 1-2, it can be seen that in the present application, the combination of flotation-spiral chute-multi-stage table sorting, each sorting step cannot be cut off, and needs to be strictly executed in order, in order to obtain the effect that the grade and recovery rate of carbon powder, copper foil powder and aluminum foil powder are both high.

[0046] Unlike the prior art, the present application provides a method for separating carbon powder, copper powder and aluminum powder from waste power battery black powder material, by preparing the black powder into a suspension to perform flotation roughing first, then performing flotation cleaning to separate qualified graphite carbon powder, and then performing spiral chute and multi-stage table reselection on the black powder after flotation scavenging and decarburization, finally separating copper foil powder, aluminum foil powder and electrode powder, and the separated carbon powder, copper foil powder and aluminum foil powder all have high grade and recovery rate, significantly improving the recycling rate of waste power battery black powder material.

[0047] The above embodiments only express the embodiments of the present application, which are described in detail and specifically, but should not be understood as limiting the scope of the patent. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of the present application. Therefore, the scope of protection of the present application patent should be subject to the appended claims.

Claims

1. A method for separating carbon powder, copper powder and aluminum powder from waste power battery black powder material, characterized in that, The steps include: Flotation roughing: The crushed raw ore with a particle size of -0.6mm is subjected to flotation and screened to separate into flotation roughing tailings and flotation roughing concentrate; Flotation scavenging: The flotation rougher tailings are subjected to flotation scavenging, and after screening, they are divided into flotation scavenging tailings and flotation scavenging concentrate; Flotation Refinement: The rougher concentrate is subjected to flotation refinement and screening, and is separated into carbon powder material and flotation tailings. The flotation tailings and flotation scavenger concentrate are collected and refluxed for the flotation roughing step again. Spiral sluice box separation: The flotation scavenging tailings are introduced into a spiral sluice box for washing. After washing, the tailings are separated into spiral sluice box tailings and spiral sluice box concentrate. The spiral sluice box concentrate is recovered as electrode powder. Primary shaking table separation: The tailings from the spiral chute are introduced into a shaking table for water washing, and after washing, they are separated into primary coarse particles, primary medium particles and primary fine particles. Secondary shaking table separation: The primary medium-particle ore is introduced into a shaking table for water washing. After washing, it is separated into secondary coarse-particle ore, secondary medium-particle ore and secondary fine-particle ore. The secondary medium-particle ore is returned to the primary shaking table separation step again. The primary fine-particle ore and the secondary fine-particle ore are collected as electrode powder for recovery. Three-stage shaking table separation: The primary and secondary coarse ore particles are introduced into the shaking table for water washing. After washing, there are tertiary coarse ore particles, tertiary medium ore particles, and tertiary fine ore particles. The tertiary coarse ore particles are recovered as copper powder, the tertiary medium ore particles are returned to the shaking table for the three-stage shaking table separation step again, and the tertiary fine ore particles are recovered as aluminum powder. The process conditions for the flotation roughing are as follows: aeration rate of 20-60 ml / min, pH value of 6-8, kerosene content of 100-500 g / t, and flotation time of 1-4 min. The process conditions for the flotation scavenging step are: aeration rate of 40-120 ml / min, pH value of 6-8, kerosene content of 100-250 g / t, and flotation time of 3-6 min. The aeration rate in the roughing flotation step is less than that in the scavenging flotation step, so that as much of the smaller carbon powder material as possible can be screened out in advance. In the spiral chute step, the water flow rate is set to the maximum to first screen out the electrode powder. In the first-stage shaking table separation, second-stage shaking table separation, and third-stage shaking table separation steps, the water flow rate is set to increase sequentially. Through the gradient increasing shaking table screening settings, impurities are gradually washed away, so that the final aluminum and copper powder products have a high grade.

2. The method for separating carbon powder, copper powder and aluminum powder from waste old power battery black powder material according to claim 1, characterized in that, The process conditions for the flotation and refining step are as follows: aeration rate of 80-120 ml / min, pH value of 6-8, kerosene content of 50 g / t, and flotation time of 3-6 min.

3. The method for separating carbon powder, copper powder and aluminum powder from waste old power battery black powder material according to claim 1, characterized in that, The water flow rate in the spiral chute step is 14-16 L / min.

4. The method for separating carbon powder, copper powder and aluminum powder from waste old power battery black powder material according to claim 1, characterized in that, The water flow rate in the first-stage shaking table sorting step is 4-6 L / min.

5. The method for separating carbon powder, copper powder, and aluminum powder from waste power battery black powder according to claim 1, characterized in that, The water flow rate in the secondary shaking table sorting step is 7-9 L / min.

6. The method for separating carbon powder, copper powder, and aluminum powder from waste power battery black powder according to claim 1, characterized in that, The water flow rate in the three-stage shaking table sorting step is 10-13 L / min.

7. The method for separating carbon powder, copper powder, and aluminum powder from waste power battery black powder according to claim 1, characterized in that, The process preceding the flotation roughing step also includes: The waste power batteries are disassembled, discharged, cleaned and dried, crushed in the first stage, pyrolyzed and crushed in the second stage to obtain raw ore with a particle size of -0.6mm.

8. The method for separating carbon powder, copper powder, and aluminum powder from waste power battery black powder according to claim 7, characterized in that, The slag after the pyrolysis step contains a metal mixture and electrode active materials. After cooling, the slag is subjected to secondary crushing to obtain the raw ore.

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