1. Project Background
Material Characteristics: Natural graphite from Tanzania is renowned for its high crystallinity, stable carbon content, and intact flake structure. However, due to its inherent toughness and layered lubricating properties, graphite is notoriously difficult to grind to micron-level sizes in traditional mechanical mills and is prone to particle agglomeration.
Customer Requirements: The client aimed to use the graphite as a precursor for high-end lubricants, conductive coatings, or lithium-ion battery anode materials. This required extreme precision in particle size distribution (PSD) and ultra-fineness, with a target particle size of d97 ≤4μm. To meet these high standards, the project focused on the ultra-fine grinding of natural graphite using advanced fluid-dynamics.
2. Core Equipment: MQW Series Jet Mill
To address the physical properties of graphite, we selected the Epic Powder MQW Series Fluidized Bed Jet Mill for ultra-fine grinding of natural graphite.
Technical Advantages of the MQW Series:
- Self-Grinding Mechanism: It utilizes supersonic airflow to cause high-velocity collisions between graphite particles. This maximizes the preservation of the graphite’s natural physical properties while eliminating secondary metallic contamination.
- Integrated Precision Classification: The horizontal high-speed classifying wheel design allows for precise control over the PSD—a critical factor in achieving a size of less than 4μm.
- Isothermal Grinding: The cooling effect of the expanding compressed gas offsets the heat generated during grinding, protecting the crystalline structure of the graphite.
3. Process Parameters & Experimental Results
During testing at our R&D center, process parameters were optimized specifically for the Tanzanian graphite:
| Indicator | Experimental Parameters |
| Feed Size | 100-200 mesh (Coarse Powder) |
| Finished Product d97 | 3.76 μm |
| Classifier Speed | 5,500 – 6,200 RPM (Adjusted by model) |
| Grinding Pressure | 0.7 – 0.8 MPa |
| Particle Morphology | Intact flake structure with excellent dispersibility |