Energy-Saving and Consumption-Reducing High-Alumina Balls (Alumina Ceramic Grinding Balls) for Ball Mill

As a high-efficiency fine-grinding equipment, ball mills are widely used in industrial fields such as metallurgy and chemical engineering. Using alumina ceramic grinding balls in ball mills improves the dissociation degree of ores, reduces over-grinding, and removes surface impurities from minerals, effectively optimizing mineral processing indicators. However, steel balls used as grinding media in ball mills are prone to causing over-grinding of materials. Additionally, impurity iron generated by steel ball wear enters the process, covering the ore surface, increasing reagent consumption, and raising production costs. Therefore, finding new grinding media to replace steel balls and reduce impurity iron in the leaching process is crucial for minimizing process impurities and costs.

Alumina ceramics exhibit excellent acid/alkali resistance, wear resistance, and other properties, adapting to harsh working conditions where many metals and nonmetals fail. As an application of engineering ceramics, alumina ceramics are widely used in fine-grinding equipment such as ball mills and vertical spiral stirring mills.

Introduction to High-Alumina Balls (Alumina Ceramic Grinding Balls)

High-alumina balls, also known as alumina ceramic balls, are wear-resistant ceramic products made from α-alumina powder as the base material, formed by rolling or pressing, and sintered at 1,600°C.

1. Characteristics of Alumina Ceramic Balls:

(1) High Hardness: Mohs hardness of 9 (second only to diamond, Mohs hardness 10).
(2) Excellent Wear Resistance: Slow consumption rate.
(3) Corrosion Resistance: Inert alumina does not react with acids or alkalis, avoiding corrosion in acidic conditions.
(4) High Strength: Low ball breakage rate, maintains shape after use.
(5) High Density (>3.6 g/cm³): Half the density of steel balls, reducing over-grinding, equipment wear, noise, and power consumption in fine-grinding conditions.
(6) Non-Toxic and Environmentally Friendly: Complies with EU RoHS restrictions on hazardous substances.

Customer Case Study:

Jiangxi Copper Corporation, Dexing Copper Mine, Stage II Ore Dressing

• Ball Mill Model: Φ2.1×3.0 (m) overflow-type ball mill
• Feed: -200 mesh, 40%
• Discharge: -200 mesh, >92%

Calculation Parameters:

1. Daily raw ore processing: 20,000 t; annual working days: 330
2. Number of stage II ball mills: 5; filling rate: 35%
3. Wear rates: High-alumina balls 0.005 kg/t·ore; metal balls 0.028 kg/t·ore
4. Energy consumption: High-alumina balls 0.084 kWh/t·ore; metal balls 0.2 kWh/t·ore
5. Prices: High-alumina balls ¥0.86 million/t; metal balls ¥0.48 million/t
6. Electricity price: ¥0.6/kWh

(II) Calculation Results:

1. Initial Ball Charge:

   • High-alumina balls: 5 × 2.3 × 9 × 35% = 36.23 t
   • Metal balls: 5 × 4.75 × 9 × 35% = 74.81 t

2. Annual Wear:

   • High-alumina balls: 0.005 × 20,000 × 330 = 33 t
   • Metal balls: 0.028 × 20,000 × 330 = 184.8 t

3. Annual Energy Consumption:

   • High-alumina balls: 0.084 × 20,000 × 330 = 554,400 kWh
   • Metal balls: 0.2 × 20,000 × 330 = 1,320,000 kWh

4. Cost Savings on Initial Ball Charge:

   • High-alumina balls: 36.23 × 0.86 = ¥311,600
   • Metal balls: 74.81 × 0.48 = ¥359,100
   • Savings: 359,100 – 311,600 = ¥47,500

5. Annual Wear Cost Savings:

   • High-alumina balls: 33 × 0.86 = ¥283,800
   • Metal balls: 184.8 × 0.48 = ¥887,040
   • Savings: 887,040 – 283,800 = ¥603,240

6. Annual Energy Cost Savings:

   • (1,320,000 – 554,400) × 0.6 = ¥459,360

Total Annual Savings:
In addition to the ¥47,500 saved on the initial ball charge, high-alumina balls are expected to save ¥603,240 (wear) + ¥459,360 (energy) = ¥1,062,600 annually.

Conclusion

High-alumina balls are made from selected high-quality raw materials using advanced forming technology and sintered in high-temperature tunnel kilns. They feature high density, high hardness, low wear rate, excellent seismic stability, and corrosion resistance, making them ideal grinding media for glazes, ceramic bodies, and various mineral powders.

In 2016, Jiangxi Copper Corporation took the lead in introducing high-alumina balls in the nonferrous metals industry, conducting experimental research on replacing metal balls with alumina grinding balls in the stage II re-grinding system of Dexing Copper Mine’s Sizhou Ore Dressing Plant. Results from nearly a year of on-site testing show:

1. High-alumina balls exhibit lower noise, maintain shape, and resist cracking compared to metal balls.
2. With the same filling rate, high-alumina balls reduce ball charge by 51.58% due to their lower specific gravity.
3. Wear rate decreases by 82.14%, and energy consumption decreases by 58% compared to metal balls.
4. High-alumina balls do not contaminate the separation process or affect separation efficiency.