A method and system for crushing and screening waste lithium-ion batteries

Abstract

The application provides a waste lithium ion battery crushing and screening method, which comprises the following steps: conveying the waste lithium ion battery to an electrified crushing device for crushing; conveying the crushed material to a low-temperature drying system to dry electrolyte; conveying the dried crushed material to a primary screening system and a diaphragm sorting system in sequence, conveying the copper foil and the aluminum foil with a particle size of 0.15-2 mm to a fine crushing system; conveying the crushed material from the fine crushing system to a secondary screening system and a magnetic separator in sequence to select magnetic impurities in the material; conveying the material after the magnetic selection to a copper-aluminum sorting system to screen copper powder and aluminum powder from the material according to different specific gravities of the material. The waste lithium ion battery crushing and screening method provided by the application realizes the recycling of waste lithium ion batteries in a fast, efficient, low-energy-consumption, safe and environmentally friendly manner. The application further provides a waste lithium ion battery crushing and screening system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of waste lithium ion battery recycling, in particular to a waste lithium ion battery crushing and screening method and system. BACKGROUND

[0002] Electric energy is the main form of secondary energy in the world today. Since the development and utilization of lithium ion batteries as a new type of energy storage method in the 1990s, due to their high energy density, light weight, long cycle life, no memory effect, green environmental protection and other advantages, they have been widely used in portable electronic devices such as mobile phones, notebook computers and cameras. The use of lithium batteries has rapidly increased and is showing a rapid growth trend. At the same time, a large number of lithium batteries are facing retirement. In order to prevent resource waste and environmental pollution, the research on the recycling of waste lithium ion batteries has important practical significance.

[0003] The prior art adopts a method of crushing and screening after salt water discharge, which causes great environmental pollution to salt water discharge; and adopts a high-temperature calcination furnace to crack the diaphragm, which has high power consumption and exists the risk of explosion.

[0004] Therefore, it is necessary to provide a new process to solve the above technical problems. SUMMARY

[0005] The present application aims to overcome the deficiencies in the prior art, and provides a waste lithium ion battery crushing and screening method and system, which realizes the recycling of waste lithium ion batteries in a fast, efficient, low-energy, safe and environmentally friendly manner.

[0006] The technical solution of the present application is as follows:

[0007] A waste lithium ion battery crushing and screening method, comprising the following steps:

[0008] Step S1, placing the waste lithium ion battery into a battery feeding device, and conveying the waste lithium ion battery to a live crushing device by the battery feeding device;

[0009] Step S2, crushing the waste lithium ion battery in the live crushing device to form a material with a width less than 20mm, and the live crushing device is in an inert gas protection atmosphere with an oxygen concentration less than 3%;

[0010] Step S3, conveying the crushed material to a low-temperature drying system to dry the electrolyte, the drying time is greater than 20min, and the drying temperature is 100-300℃;

[0011] Step S4, the crushed material after drying enters the first screening system, and the dried material is screened according to the size into three parts, which are black powder with a particle size less than 100 mesh, copper foil and aluminum foil with a particle size of 0.15-2 mm, and shell and diaphragm fragments with a particle size greater than 2 mm;

[0012] Step S5, after the first screening, the material with a particle size greater than 2 mm is sent to the diaphragm sorting system, and through the airflow winnowing screening, the light diaphragm is blown up by the airflow and collected, and the heavy shell is collected under the winnowing system; the black powder with a particle size less than 100 mesh is collected by negative pressure pipeline; the copper foil and aluminum foil with a particle size of 0.15-2 mm are transported to the fine crushing system;

[0013] Step S6, the fine crushing system adopts the throwing knife crushing method to crush the material to a particle size of less than 2 mm;

[0014] Step S7, the material after the fine crushing system enters the second screening system for secondary screening, and the material is divided into two parts, which are black powder with a particle size less than 100 mesh, and material with a particle size greater than 100 mesh;

[0015] Step S8, after the second screening, the black powder with a particle size less than 100 mesh is collected by negative pressure pipeline; the material with a particle size greater than 100 mesh is transported to the first magnetic separator to screen out the magnetic impurities in the material;

[0016] Step S9, the material after the magnetic separation enters the copper-aluminum sorting system, and the copper powder and aluminum powder are screened out by the different specific gravity of the material;

[0017] Step S10, secondary magnetic separation is carried out by the second magnetic separator to further remove the magnetic impurities in the copper powder and aluminum powder to obtain the recovered material;

[0018] The dust generated in the crushing and sorting process of each step is collected by the pulse dust collector, and the waste gas is treated by the tail gas treatment system.

[0019] Further, in step S1, the battery feeding device transports the waste lithium ion battery to the electrified crushing device, and the process adopts a hopper automatic lifting feeding mode.

[0020] Further, in step S2, argon or nitrogen protection is used in the electrified crushing device.

[0021] Further, in step S3, the low-temperature drying system adopts electric heating or natural gas heating.

[0022] Further, in step S6, the motor of the fine crushing system is controlled by a servo driver, and the motor speed is adjustable.

[0023] Further, in step S8, the magnetic field strength of the magnetic roller used by the first magnetic separator is greater than 4000 Gauss.

[0024] Further, in step S9, after the copper-aluminum separation, the aluminum content in the copper powder is less than 1.5wt%, and the copper powder recovery efficiency is greater than 98%; the copper content in the aluminum powder is less than 1.5wt%, and the aluminum powder recovery efficiency is greater than 98%.

[0025] Further, in step S10, the magnetic field strength of the magnetic roller used by the secondary magnetic separator is greater than 4000 Gauss.

[0026] Further, the tail gas treatment system comprises, in sequence, a bag dust collector, a TO furnace, a gas-gas heat exchanger, a quenching tower, a primary alkali washing tower, a secondary alkali washing tower, a mist removal device and a sludge filter pressing device.

[0027] The application also provides a waste lithium ion battery crushing and screening system, comprising:

[0028] a battery feeding device, an electric crushing device, a low-temperature drying system, a primary screening system, a separator separation system, a fine crushing system, a secondary screening system, a first magnetic separator, a copper-aluminum separation system and a second magnetic separator arranged in sequence according to the material processing flow;

[0029] a black powder collecting device for collecting the black powder generated in the crushing and separation process;

[0030] a pulse dust collector for collecting the dust generated in the crushing and separation process;

[0031] and a tail gas treatment system for treating the waste gas generated in the crushing and separation process;

[0032] The electric crushing device is in an inert gas protection atmosphere, and the oxygen concentration is controlled to be less than 3%;

[0033] The heating temperature of the low-temperature drying system is 100-300 DEG C;

[0034] The primary screening system screens the dried material into three parts according to the size, which are black powder with a particle size less than 100 mesh, copper foil and aluminum foil with a particle size of 0.15-2mm, and shells and separator fragments with a particle size greater than 2mm;

[0035] The separator separation system separates the materials with a particle size greater than 2mm into separator and shells through airflow winnowing screening;

[0036] The fine crushing system is used for crushing the copper foil and aluminum foil after the primary screening, and crushing the material particle size to less than 2mm;

[0037] The secondary screening system is used for secondary screening of the material crushed by the fine crushing system, and separates black powder with a particle size less than 100 mesh and material with a particle size greater than 100 mesh.

[0038] The first magnetic separator is used for magnetic separation of the material screened secondarily, and screens out magnetic impurities in the material.

[0039] The copper-aluminum separation system is used for separation treatment of the material after the first magnetic separation, and separates copper powder and aluminum powder through different specific gravities of the material.

[0040] The second magnetic separator is used for secondary magnetic separation of the separated copper powder and aluminum powder.

[0041] Compared with the prior art, the waste lithium ion battery crushing and screening method and system provided by the application has the beneficial effects that:

[0042] Firstly, the waste lithium ion battery crushing and screening method and system provided by the application adopts an electrified crushing process, does not need to discharge the waste lithium ion battery, has high recovery efficiency, and avoids pollution to the environment caused by salt water discharge.

[0043] Secondly, the waste lithium ion battery crushing and screening method and system provided by the application collects the separator by using a low-temperature drying furnace in cooperation with a separator separation system, avoids decomposition of the separator through low-temperature drying, and has low power consumption, safety, and environmental friendliness.

[0044] Thirdly, the waste lithium ion battery crushing and screening method and system provided by the application collects black powder and dust in a centralized manner, reduces the risk of dust pollution and dust explosion.

[0045] Fourthly, the waste lithium ion battery crushing and screening method and system provided by the application meets tail gas emission standards through a tail gas treatment system, and makes the recovery process harmless to the environment. BRIEF DESCRIPTION OF DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0047] Figure 1 It is a flowchart of the waste lithium ion battery crushing and screening method of the application.

[0048] Figure 2 It is a structural schematic diagram of the waste lithium ion battery crushing and screening system of the application. DETAILED DESCRIPTION

[0049] In order to better understand the technical solutions in the embodiments of the present application by those skilled in the art, and to make the above-mentioned purposes, features and advantages of the present application more apparent and easy to understand, the specific embodiments of the present application are further described below.

[0050] The endpoints of the ranges and any values disclosed herein are not limited to the precise values recited as the exact dimensions are not critical to the present application. Any numerical value, however, can be expressed as a range by either adding or subtracting a small percentage (e.g., 1-10%) from the stated value to account for variations, measurement inaccuracies, and the like. For numerical ranges expressed in the format "from X to Y," it is intended that embodiments "X" and "Y" are included within the range. Likewise, when numerical ranges are expressed in the format "X - Y," it is intended that embodiments "X" and "Y" are included in the range.

[0051] A waste lithium ion battery crushing and screening method, comprising the following steps:

[0052] Step S1, the waste lithium ion battery is put into a battery feeding device, and the battery feeding device delivers the waste lithium ion battery to an electrified crushing device;

[0053] Specifically, the battery feeding device delivers the waste lithium ion battery to the electrified crushing device, and the process adopts a hopper automatic lifting feeding mode, which can reduce the risk of personnel injury.

[0054] Step S2, the waste lithium ion battery is crushed in the electrified crushing device, the electrified crushing device adopts a tearing crushing mode to crush the battery into materials with a width less than 20 mm, and the electrified crushing device is in an inert gas protection atmosphere, and the oxygen concentration is controlled to be less than 3%; wherein the inert gas is argon or nitrogen;

[0055] Step S3, the crushed materials are delivered to a low-temperature drying system to dry the electrolyte, and the drying temperature is less than 300 DEG C;

[0056] Specifically, an electric heating or natural gas heating mode can be adopted, and the heating time is greater than 20 min, the materials are dried at low temperature, and the decomposition of the separator in the drying process can be avoided.

[0057] Step S4, the crushed materials after drying enter a primary screening system, and the materials after drying are screened into three parts according to the size, which are black powder with a particle size less than 100 mesh, copper foil and aluminum foil with a particle size of 0.15-2 mm, and shells and separator fragments with a particle size greater than 2 mm;

[0058] Step S5, after the primary screening, the materials with a particle size greater than 2 mm are sent to a separator sorting system, and are screened by airflow winnowing, the light separator is blown up by the airflow and collected, the shells with a heavier mass are collected under the lower layer of the winnowing system, the black powder with a particle size less than 100 mesh is collected by a negative pressure pipeline, and the copper foil and aluminum foil with a particle size of 0.15-2 mm are delivered to a fine crushing system;

[0059] Step S6, the fine crushing system adopts a flail crusher to crush the material to a particle size of less than 2 mm, wherein the motor of the fine crushing system is controlled by a servo driver, and the motor speed is adjustable;

[0060] Step S7, the material crushed by the fine crushing system enters a two-stage screening system for two-stage screening, and the material is divided into two parts, i.e., black powder with a particle size of less than 100 mesh and material with a particle size of greater than 100 mesh;

[0061] Step S8, after two-stage screening, the black powder with a particle size of less than 100 mesh is collected by a negative pressure pipeline, and the material with a particle size of greater than 100 mesh is transported to a first magnetic separator to screen out magnetic impurities in the material;

[0062] The magnetic field strength of the magnetic roller used in the first magnetic separator is greater than 4000 Gauss;

[0063] Step S9, the material after magnetic separation enters a copper-aluminum separation system to screen out copper powder and aluminum powder through different specific gravities of the material; after copper-aluminum separation, the aluminum content in the copper powder is less than 1.5wt%, and the copper powder recovery efficiency is greater than 98%; the copper content in the aluminum powder is less than 1.5wt%, and the aluminum powder recovery efficiency is greater than 98%;

[0064] Step S10, secondary magnetic separation is performed by a second magnetic separator to further remove magnetic impurities in the copper powder and the aluminum powder to obtain recovered material, wherein the magnetic field strength of the magnetic roller used in the secondary magnetic separation is greater than 4000 Gauss;

[0065] The dust generated in each step of the crushing and separation process is collected by a pulse dust collector, and the waste gas is treated by a tail gas treatment system, wherein the tail gas treatment system comprises, in sequence, a bag dust collector, a TO furnace, a gas-gas heat exchanger, a quenching tower, a primary alkali washing tower, a secondary alkali washing tower, a demisting device and a sludge filter pressing device. The tail gas treatment system meets the tail gas emission standard, so that the recovery process is harmless to the environment.

[0066] The waste old lithium ion battery crushing and screening method of the application realizes the recovery of waste old lithium ion batteries in a fast, efficient, low-energy, safe and environmentally friendly manner.

[0067] The application further provides a waste old lithium ion battery crushing and screening system, comprising:

[0068] The material processing process comprises, in sequence, a battery feeding device 1, a live crushing device 2, a low-temperature drying system 3, a primary screening system 4, a separator separation system 5, a fine crushing system 6, a two-stage screening system 7, a first magnetic separator 8, a copper-aluminum separation system 9 and a second magnetic separator 10;

[0069] A black powder collecting device 11 for collecting black powder generated in the crushing and sorting process;

[0070] A pulse dust collector 12 for collecting dust generated in the crushing and sorting process;

[0071] A tail gas treatment system 13 for treating exhaust gas generated in the crushing and sorting process;

[0072] The material of the battery feeding device 1 is automatically lifted and conveyed to the electrified crushing device 2 through the hopper.

[0073] The electrified crushing device is in an inert gas protective atmosphere, such as argon or nitrogen, and the oxygen concentration is controlled to be less than 3%.

[0074] The heating temperature of the low-temperature drying system 3 is less than 300°C, such as 100-300°C, and electric heating or gas heating can be used.

[0075] The first screening system 4 screens the dried material according to the size into three parts, which are black powder with a particle size less than 100 mesh, copper foil and aluminum foil with a particle size of 0.15-2mm, and shell and diaphragm fragments with a particle size greater than 2mm.

[0076] The diaphragm sorting system 5 separates the material with a particle size greater than 2mm into diaphragm and shell through air flow winnowing screening. Specifically, the light diaphragm is blown up by the air flow and collected, and the heavy shell is collected at the lower layer of the winnowing system.

[0077] The fine crushing system 6 is used to crush the copper foil and aluminum foil after the first screening, and the particle size of the material is crushed to less than 2mm. The motor of the fine crushing system is controlled by a servo driver, and the motor speed is adjustable.

[0078] The second screening system 7 is used to perform secondary screening on the material crushed by the fine crushing system, and separate black powder with a particle size less than 100 mesh and material with a particle size greater than 100 mesh.

[0079] The first magnetic separator 8 is used to magnetically separate the material after the second screening, and separate the magnetic impurities in the material. The magnetic field strength of the magnetic roller used in the first magnetic separator is greater than 4000 Gauss.

[0080] The copper-aluminum sorting system 9 is used to sort the material after the first magnetic separation. The copper powder and aluminum powder are separated by the different specific gravities of the material. After copper-aluminum separation, the aluminum content in the copper powder is less than 1.5wt%, and the copper powder recovery efficiency is greater than 98%; the copper content in the aluminum powder is less than 1.5wt%, and the aluminum powder recovery efficiency is greater than 98%.

[0081] The second magnetic separator 10 is used for secondary magnetic separation of the screened copper powder and aluminum powder, further removes the magnetic impurities in the copper powder and aluminum powder, and obtains the recovered material. The magnetic field strength of the magnetic roller used in the second magnetic separator 10 is greater than 4000 Gauss.

[0082] The black powder collecting device 11 is used for collecting the black powder generated in each crushing and sorting process, and specifically collects through a negative pressure pipeline.

[0083] The waste lithium ion battery crushing and screening system provided by the application collects the black powder and dust in a centralized manner, reduces the risk of dust pollution and dust explosion.

[0084] The tail gas treatment system of the waste lithium ion battery crushing and screening system provided by the application meets the tail gas emission standard, so that the recycling process is harmless to the environment.

[0085] The above describes the embodiments of the application in detail, but the application is not limited to the described embodiments. Various changes, modifications, replacements and variations of the embodiments made by those skilled in the art without departing from the principles and spirits of the application still fall within the protection scope of the application.

Claims

1. A method for crushing and screening waste lithium-ion batteries, characterized in that, Includes the following steps: Step S1: Place the waste lithium-ion batteries into the battery feeding device, which then transports the waste lithium-ion batteries to the live crushing device. Step S2: The waste lithium-ion batteries are crushed in the live crushing device to break them into materials with a width of less than 20mm. The live crushing device is in an inert gas protective atmosphere, and the oxygen concentration is controlled to be less than 3%. Step S3: The crushed material is conveyed to a low-temperature drying system to dry the electrolyte at a temperature of 100-300℃. Step S4: The dried crushed material enters the primary screening system, which separates the dried material into three parts according to size: black powder with a particle size of less than 100 mesh, copper foil and aluminum foil with a particle size of 0.15-2 mm, and shell and membrane fragments with a particle size of more than 2 mm. Step S5: After primary screening, materials with a particle size greater than 2 mm are sent to the diaphragm separation system. Through airflow classification, the light diaphragm is blown up and collected by the airflow, while the heavier outer shell is collected in the lower layer of the air classification system. Black powder with a particle size less than 100 mesh is collected by a negative pressure pipeline. Copper foil and aluminum foil with a particle size of 0.15-2 mm are conveyed to the fine crushing system. Step S6: The fine crushing system uses a blade crushing method to crush the material to a particle size of less than 2mm. Step S7: The material crushed by the fine crushing system enters the secondary screening system for secondary screening, which divides the material into two parts: black powder with a particle size of less than 100 mesh and material with a particle size of more than 100 mesh. In step S8, after secondary screening, black powder with a particle size less than 100 mesh is collected using a negative pressure pipeline; material with a particle size greater than 100 mesh is conveyed to the first magnetic separator to screen out magnetic impurities in the material. Step S9: The magnetically separated material enters the copper-aluminum separation system, where copper powder and aluminum powder are separated by different specific gravities of the material. Step S10: Secondary magnetic separation is performed using a second magnetic separator to further remove magnetic impurities from copper and aluminum powder, thereby obtaining recycled material; The dust generated during each crushing and sorting process is collected centrally by a pulse dust collector, and the waste gas generated is treated by a tail gas treatment system.

2. The method for crushing and screening waste lithium-ion batteries according to claim 1, characterized in that, In step S1, the battery feeding device transports the waste lithium-ion batteries to the charged crushing device. This process adopts an automatic hopper lifting feeding method.

3. The method for crushing and screening waste lithium-ion batteries according to claim 1, characterized in that, In step S2, the energized crushing device is protected by argon or nitrogen.

4. The method for crushing and screening waste lithium-ion batteries according to claim 1, characterized in that, In step S3, the low-temperature drying system uses electric heating or natural gas heating.

5. The method for crushing and screening waste lithium-ion batteries according to claim 1, characterized in that, In step S6, the motor of the fine crushing system is controlled by a servo driver, and the motor speed is adjustable.

6. The method for crushing and screening waste lithium-ion batteries according to claim 1, characterized in that, In step S8, the magnetic field strength of the magnetic roller used in the first magnetic separator is greater than 4000 Gauss.

7. The method for crushing and screening waste lithium-ion batteries according to claim 1, characterized in that, In step S9, after copper and aluminum separation, the aluminum content in the copper powder is less than 1.5 wt%, and the copper powder recovery efficiency is greater than 98%; the copper content in the aluminum powder is less than 1.5 wt%, and the aluminum powder recovery efficiency is greater than 98%.

8. The method for crushing and screening waste lithium-ion batteries according to claim 1, characterized in that, In step S10, the magnetic field strength of the magnetic roller used in the secondary magnetic separation is greater than 4000 Gauss.

9. The method for crushing and screening waste lithium-ion batteries according to claim 1, characterized in that, The exhaust gas treatment system includes, in sequence: a bag filter, a TO furnace, a gas-to-gas heat exchanger, a quench tower, a primary alkaline scrubbing tower, a secondary alkaline scrubbing tower, a demister, and a sludge filter press.

10. A waste lithium-ion battery crushing and screening system, characterized in that, include: The battery feeding device, charged crushing device, low temperature drying system, primary screening system, diaphragm sorting system, fine crushing system, secondary screening system, first magnetic separator, copper-aluminum sorting system and second magnetic separator are set up in sequence according to the material handling process. A black powder collection device for the centralized collection of black powder generated during the crushing and sorting process; A pulse dust collector used to collect dust generated during the crushing and sorting process; And a tail gas treatment system for treating the waste gas generated during the crushing and sorting process; The electric crushing device is equipped with an inert gas protective atmosphere, and the oxygen concentration is controlled to be less than 3%. The heating temperature of the low-temperature drying system is 100-300℃; The primary screening system separates the dried material into three parts according to size: black powder with a particle size of less than 100 mesh, copper foil and aluminum foil with a particle size of 0.15-2 mm, and shell and membrane fragments with a particle size of more than 2 mm. The diaphragm sorting system separates materials with a particle size greater than 2mm into diaphragms and outer shells through airflow classification and screening. The fine crushing system is used to crush copper foil and aluminum foil after primary screening and to crush the material particle size to within 2mm; The secondary screening system is used to perform secondary screening on the material after it has been crushed by the fine crushing system, separating black powder with a particle size of less than 100 mesh and material with a particle size of more than 100 mesh. The first magnetic separator is used to magnetically separate the material after secondary screening to remove magnetic impurities from the material; The copper-aluminum separation system is used to separate materials after a single magnetic separation, separating copper powder and aluminum powder based on the different specific gravities of the materials. The second magnetic separator is used for secondary magnetic separation of the sieved copper and aluminum powders.

Images