1. Project Background
Petroleum Coke is a by-product of the oil refining process, characterized by high carbon content and high calorific value. However, in applications such as lithium-ion battery anode materials, high-end graphite products, and specialty fuels, the particle size distribution of petroleum coke directly determines its added value.
As a global oil powerhouse, Saudi Arabia produces petroleum coke with moderate hardness but a distinct fibrous structure. In this project, the customer required the raw material to be ground from its original state down to an ultrafine level of D90: 5 μm, with an extremely narrow particle size distribution. This requirement places exceptionally high demands on equipment performance and process control in the field of ultrafine grinding of petroleum coke, especially for high-end downstream applications.
2. Core Challenges
- Extremely high fineness requirement: A D90 of 5 μm represents a submicron-level challenge. Conventional mechanical mills struggle to achieve this fineness and often lead to over-grinding.
- Purity protection: Petroleum coke is highly sensitive to impurities—especially metallic contaminants—making it essential to prevent secondary contamination during processing.
- Energy consumption control: Ultrafine grinding of petroleum coke is typically associated with high energy consumption, so improving grinding efficiency is critical for cost reduction and productivity.
3. Technical Solution: Epic Powder Jet Mill System
Based on the characteristics of Saudi petroleum coke, Epic Powder selected a Fluidized Bed Jet Mill as the core processing equipment.
Key technical advantages:
- Autogenous grinding principle: Particles are accelerated by high-velocity airflow and pulverized through inter-particle collisions and friction, with no direct contact with metal grinding media—effectively ensuring product purity.
- High-efficiency classification: The system integrates a high-precision horizontal classifier wheel. By adjusting the rotational speed, the cut size can be accurately controlled, ensuring a D90 of 5 μm while effectively rejecting oversized particles.
- Isothermal grinding: The expansion of compressed air absorbs heat and offsets the heat generated during grinding, maintaining the physical and chemical stability of petroleum coke.
4. Test Data and Results
After multiple rounds of commissioning and system optimization, the equipment operated stably, and the final product fully met customer expectations:
| Parameter | Raw Material | Finished Product |
|---|---|---|
| Appearance | Black granules / lumps | Black ultrafine powder |
| Particle size (D90) | ~2 mm | 4.82 μm |
| Particle size distribution | Broad | Typical narrow normal distribution |
| Moisture content | <1% | <0.5% |