Negative electrode crushing and recycling equipment

Brief introduction

Lithium ion batteries (hereinafter referred to as lithium-ion batteries), due to their significant advantages such as high voltage, large specific capacity, long lifespan, and no memory effect, have quickly occupied the power source market of portable electronic and electrical equipment since their commercialization, and their production has been increasing year by year. Lithium batteries are electronic consumables with a lifespan of approximately 3 years. If discarded lithium batteries are not properly disposed of, their containing lithium hexafluorophosphate, organic compounds such as carbonates, and heavy metals such as cobalt and copper will inevitably pose a potential pollution threat to the environment. To alleviate the increasingly serious resource shortage and environmental pollution caused by rapid economic development, achieving full component recycling of waste materials has become a global consensus.

Copper (with a content of about 35%) in the negative electrode of waste lithium batteries is a widely used important supply material. Carbon powder adhered to it can be used as an additive for plastics, rubber, and other materials. Therefore, effective separation of the negative electrode components of waste lithium batteries plays a promoting role in achieving maximum resource utilization of waste lithium batteries and eliminating their corresponding environmental impacts. The commonly used methods for treating waste lithium batteries include wet, pyrometallurgical, and mechanical physical methods. Compared to wet and pyrometallurgical methods, mechanical physical methods do not require the use of chemical reagents and have lower energy consumption, making them an environmentally friendly method. Based on the structural characteristics of the negative electrode of lithium batteries, our company adopts a combination process of crushing screening and airflow sorting to separate and screen them, in order to achieve the separation and recovery of waste lithium battery negative electrode aluminum and carbon powder.

Operational principle

Based on the structure of lithium battery negative electrode and the material characteristics of copper and negative electrode materials, a combined process of hammer vibration crushing, vibration screening, and airflow sorting is adopted to separate and recover the waste lithium battery negative electrode material. The experiment used ICP-AES to analyze the metal grades of the experimental samples and the separated and enriched products. The results show that after crushing and screening, the grade of copper in the crushed material with a particle size greater than 0.250 mm is 92.4%, while the grade of the negative electrode material in the crushed material with a particle size less than 0.125mm is 96.6%, which can be directly recovered; In crushed materials with a particle size of 0.125-0.250 mm, the grade of copper is relatively low, and effective separation and recovery of copper and negative electrode materials can be achieved through air flow separation; During the airflow sorting process, when the operating airflow speed is 1.00 m/s, the copper recovery rate reaches 92.3% and the grade reaches 84.4%.

Process flow diagram

1. Crusher: Crushes the materials sorted by airflow.

2. Analysis machine: Wind select and separate the crushed materials.

3. Linear screen: Screen the materials sorted by the analyzer, and separate the metal materials and negative electrode powder.

4. Gravity sorter: The metal and black powder mixture in the linear sieve is fed into the gravity sorter for sorting.

5. Collector: Collect and discharge the negative electrode powder.

6. Pulse purifier: Collect and discharge the dust generated during the operation of the entire equipment.

Characteristic

1. The combination process of hammer vibration crushing, vibration screening, and airflow sorting can achieve the resource utilization of metallic copper and negative electrode materials in waste lithium battery negative electrode materials.

2. The negative electrode material can be effectively peeled off between carbon powder and copper foil through hammer vibration crushing, and then preliminarily separated from the negative electrode material through vibration screening based on particle size and shape differences. The results of hammer vibration stripping and screening separation show that copper and negative electrode materials are enriched in particle size ranges greater than 0.25mm and less than 0.125mm, with grades as high as 92.4% and 96.6%, respectively, and can be directly sent to downstream enterprises for recycling.

3. For crushed particles with a particle size of 0.125~0.250 mm and low copper grade, effective separation between copper and negative electrode materials is achieved through airflow separation. When the airflow speed is 1.00 m/s, good recovery results can be achieved, with a copper recovery rate of 99.5% and a grade of 84.4%.

4. This equipment is mainly used by lithium-ion battery supply companies to separate and process the negative electrode materials from discarded negative electrode plates for the purpose of recycling. The complete set of equipment operates in a negative pressure state, with no dust leakage and a separation efficiency of over 98%.

Main component configuration