Products Description
Applicable industries for lithium battery NMP recycling system: Mainly used for recycling NMP waste gas generated during the production process of lithium battery/sodium battery or NMP recycling in other industries.
Technical Parameters
| Battery NMP Recycle System | ||
|
Item |
Unit |
Specification |
| Exhaust air volume |
m³/h |
50000(Exhaust air volume of coater) |
| Air outlet temperature |
℃ |
120℃ |
| NMP consumption |
kg/h |
Above 45 |
| NMP Technical requirements for recycling |
|
|
| 1)rate of recovery |
|
≥95% |
| 2) Recovery concentration |
|
≥80% |
| 3) NMP exhaust emission concentration after recovery |
PPM |
Below 200 |
| Material of auxiliary facilities | ||
| Ventilation duct |
mm |
White iron pipe 300*300*0.0.6 |
| Process Performance Requirements | |
|
Item |
Specification |
|
Energy saving performance |
Use tube fin heat exchanger to save energy consumption. |
|
Sealing performance |
All connections in the unit are sealed with high-temperature silica gel and high-temperature glue. The air leakage rate at the connection of each functional section is less than 0.5%. |
|
Linkage performance |
Linked with the coater separately, the unit can operate under the best working conditions, and the recovered NMP concentration is more stable. |
|
Others |
After the equipment stops running, NMP cannot flow back to the air inlet pipe, and when the NMP recovery system fails, it will not affect the use of the coater. |
Display
Core Advantages
- High recovery efficiency: high recovery rate, high VOC treatment efficiency;
- Easy maintenance: the system is stable and durable;
- Small footprint: reasonable layout, high space utilization;
- Low investment cost;
- High system stability: The cooling work process is equipped with a variety of temperature instruments and online monitoring equipment to ensure system stability.
Introduction to lithium battery NMP
The main use and emission of NMP in lithium batteries are in the positive electrode preparation process. The preparation details mainly include the following points:
1.Coating Process:
- This part of the work requires the use of a coating machine. Use the equipment to evenly apply the positive electrode slurry made from materials such as lithium nickel cobalt manganate, conductive carbon black, and solvent NIP on both sides of the aluminum box, and use the negative pressure of the dryer The exhaust function dries the aluminum foil.
- During the implementation of this process, NMP volatilization will generally only occur at the aluminum foil inlet and outlet of the coating machine equipment. The dryer will collect these volatilized NMP into the exhaust gas treatment equipment and discharge it at high altitude. During the entire work process, only a small amount of NMP waste will be evaporated randomly in the workshop due to incomplete drying work.
2.Baking Process:
- The second step is baking. After the coating work is completed, technicians will place the materials into vacuum drying equipment to bake the lithium battery cathode sheets. To ensure the effect, the baking temperature needs to be set between 120°C and 5°C. time, this can also remove NNP at the electrode position. Subsequently, the gas generated by drying only needs to be introduced into the NMP recovery equipment to achieve recovery.
3.Cold pressed tablets:
- This step needs to be dried in advance, that is, the dried electrode material is introduced to the roller press through the conveyor belt for rolling. The main purpose of this step is to ensure that the flatness of the electrode material meets the specified requirements.
Lithium battery NMP recycling system process
System Design:
1. Design parameters
- Exhaust temperature:120℃;
- Treatment air volume:50000m3/h;
- Rate of recovery:≥95%;
- Concentration of recovered waste liquid:≥ 80%;
- Exhaust emission concentration:Below 200 ppm;
2. Technological process
Considering the functional requirements, building load requirements and production process requirements, most production lines install the coating machine on the first floor, and set up a waste liquid temporary storage tank and discharge pump set near the coating machine and against the outer wall. , used to collect NMP waste liquid returned from the cathode recovery system of the factory.
After the positive electrode coating exhaust air passes through the heat exchanger, it undergoes two-stage condensation with normal temperature cooling water and low-temperature chilled water (the cooling water tray and cooling water should not be eliminated) for MMP recovery. The normal temperature cooling water will use an open cooling tower to dissipate heat, and the chilled water supply and return temperature will be determined according to the specific project. The VOC adsorption wheel regeneration adopts steam heating regeneration.
The recovery system recycles most of the total exhaust air volume into the coating machine after reducing the MMP concentration, and the remaining exhaust air volume is processed by the runner absorption process to reduce the MP concentration below the environmental emission allowable level and then discharges it to high altitude. The runner processing capacity is determined based on the specific project. All NMP condensate flows by gravity into the waste storage tank.
Each set of double-layer cathode coating equipment is equipped with heat recovery and condensation recovery devices. The return air enters the coating machine after treatment by the return air filter; the recovery equipment is equipped with a runner adsorption device. The runner adsorption device uses steam disk heating and regeneration, and high-temperature regeneration air It is discharged into the front end of the two-stage condensation device for reprocessing and recovery of NMP. After treatment by the runner, the exhaust air is collected into the main pipe and led to outdoor high-altitude discharge.
