Application Case of Limestone Ball Mill Classification System with an Annual Production Capacity of 10,000 Tons in Ethiopia

Project Background

With the rapid acceleration of infrastructure development across East Africa, the Ethiopian market has shown a steadily growing demand for high-quality ultrafine calcium carbonate (limestone powder).
To achieve a high product standard of D97: 10 μm while maintaining economic efficiency in large-scale continuous production, a leading local building materials enterprise introduced an Epic Powder solution.
The project was specifically designed to balance ultrafine particle size requirements with cost-effective, high-capacity industrial operation.

Core Equipment Configuration

The production line adopts a Limestone Ball Mill Classification closed-circuit system consisting of a ball mill integrated with a high-precision air classifier:

• Grinding Unit: Epic Powder ball mill with high-alumina ceramic lining, ensuring high product whiteness and minimal iron contamination
• Classification System: ITC Series horizontal ultrafine air classifier
• Final Product Specification: D97 = 10 μm
• Production Capacity: 3 t/h (finished product output)

Limestone Ball Mill Classification System Process Flow Overview

Grinding Stage:
Raw limestone is fed into the ball mill. The grinding media impact and abrade the material, reducing it to micron and sub-micron particle sizes.

Classification Stage:
Airflow transports the ground powder into the ITC classifier, where the system performs the critical step of final quality control.

Closed-Loop Circulation:
Fine particles meeting the D97 = 10 μm target pass through the classifier wheel into the final product collector. Meanwhile, oversized particles flow back to the ball mill for regrinding, completing the stable closed-circuit loop.

Site Acceptance Results

Acceptance Item	Design Specification	Site Acceptance Results	Acceptance Conclusion
Product Particle Size (D97)	≤ 10 μm	9.5–9.8 μm (stable)	✅ Compliant
Particle Size Distribution Stability	D97 fluctuation ≤ ±5%	Fluctuation ≤ ±3%	✅ Better than design
Finished Product Capacity	3 t/h	3.0–3.2 t/h	✅ Exceeded target
System Continuous Running Time	≥ 24 h continuous operation	72 h continuous stable operation	✅ Compliant
Classification Cutting Precision	No obvious coarse particle leakage	No coarse particle leakage detected	✅ Compliant
Product Whiteness	Maintain high whiteness	Whiteness stable, no significant decrease	✅ Compliant
Iron Contamination Control	≤ Industry allowable value	No abnormal iron impurities detected	✅ Compliant