Q: What is an Air Jet Mill?
An air jet mill utilizes high-speed airflow (300-500 m/s) to make particles collide and friction against each other for ultrafine grinding. It is widely used in industries like pharmaceuticals, chemicals, and new materials, producing powders with a D50 <10μm.
Q: What is the Core Principle of Air Jet Mills?
Based on the principles of “fluid kinetic energy conversion” and “particle self-grinding,” compressed air accelerates through a Laval nozzle to form supersonic airflow. Materials experience high-frequency collisions in a fluidized bed or annular chamber for fine grinding.
Q: How Does it Differ from Traditional Mechanical Mills?
| Criteria | Air Jet Mill | Mechanical Mill |
| Energy Consumption | Higher (but finer results) | Lower |
| Contamination | No media contamination | Metal wear possible |
| Fineness | Can reach submicron levels | Typically >20μm |
| Temperature Rise | <5°C (low-temperature advantage) | Significant temperature rise |
Q: What are the Typical Structural Types of Air Jet Mills?
Main types include:
- Flat-type (Alpine)
- Circulating Tube-type (Jet-O-Mizer)
- Opposed Jet-type (Majac)
- Fluidized Bed-type (modern mainstream, e.g., CGS)
Q: How to Mitigate the Risk of Dust Explosions?
Use a triple protection system:
- Nitrogen protection system
- Electrostatic eliminators
- Explosion vent + suppression valve interlock
Q: Key Considerations for Air Jet Mill Use in the Lithium Battery Industry?
Special attention should be given to:
- Strictly controlling iron content <50ppm
- Moisture control <100ppm
- Use of inert gas closed-loop systems
Q: Key Parameters Affecting Grinding Efficiency?
The five key factors to control are:
- Nozzle pressure (optimal range: 0.7-1.2 MPa)
- Classifier wheel speed (variable frequency control)
- Feeding speed (dynamic balance required)
- Gas humidity (dew point < -40°C)
- Initial particle size (recommended <100 mesh)
Q: How to Select the Right Equipment?
Follow the “Four Look Principles”:
- Look at capacity needs (from 5 kg/h to 2 t/h)
- Look at material characteristics (Mohs hardness, moisture content)
- Look at product requirements (particle size distribution, sphericity)
- Look at process compatibility (whether inert gas is required)
Q: Daily Maintenance Considerations?
Key maintenance items:
- Check nozzle wear weekly
- Calibrate classifier wheel balance monthly
- Replace filter cartridges quarterly
- Monitor differential pressure fluctuations (normal <15 kPa)
Q: What are the Future Development Trends of Air Jet Mill Technology?
Three major innovation directions:
- Intelligentization (digital twins + AI parameter optimization)
- Low energy consumption (new supercritical CO₂ technology)
- Multi-functionality (grinding/modification/coating integration)
Epic powder
Epic Powder, 20+ years of work experience in the ultrafine powder industry. Actively promote the future development of ultra-fine powder, focusing on crushing, grinding, classifying and modification process of ultra-fine powder. Contact us for a free consultation and customized solutions! Our expert team is dedicated to providing high-quality products and services to maximize the value of your powder processing. Epic Powder—Your Trusted Powder Processing Expert !
