Optimizing Wet Ultrafine Grinding Process for Ball Mills

Wet ultrafine grinding may seem straightforward, but it comes with significant technical complexities and encompasses various aspects. In the current landscape of the ultrafine industry, the lack of common communication and the absence of unified industry standards in China have resulted in diverse choices and practices in ultrafine equipment and processes. This has led to differing opinions and approaches in ultrafine production and processes, causing significant disparities in product standards, yield standards, grinding media wear, electricity consumption, and equipment maintenance costs.

Particle Size Distribution: A Crucial Factor in Ultrafine Grinding

In the ultrafine grinding process, extensive research is dedicated to optimizing the particle size distribution of grinding media based on the feed granularity and final product fineness. Different feed fineness levels require different particle sizes of grinding media. Moreover, not all raw materials can utilize the same type of grinding media, as the selection of grinding media material and specifications varies significantly.

Temperature and Dispersion Agents Matter

As the fineness increases during grinding, viscosity also rises. It's crucial to emphasize the importance of temperature and the addition of dispersion agents. Grinding without adequate temperature control is ineffective. The ideal temperature for adding dispersion agents typically ranges from 75 to 85 degrees Celsius.

Key Metrics for Assessing Ultrafine Process Health

To assess whether the ultrafine process is operating normally and steadily, you should consider the following comprehensive indicators:

1. Fill Rate: Ensure that grinding media is filled to approximately 50% capacity in ball mills and stirred mills.

2. Current: The grinding media must be added within the specified current range.

3. Temperature: Effective ultrafine grinding occurs at temperatures between 70 and 80 degrees Celsius.

4. Flow Rate: Evaluate the final production yield.

Wet Grinding Techniques for Ball Mills

Based on practical experience and recommendations, it's crucial to adopt the drip-feeding method during fine grinding rather than adding all the material at once. Quantitative use of dispersion agents and adjustment of slurry flow rates are essential to ensure product fineness. Some manufacturers lack a uniform standard for adding grinding media, and arbitrary additions are considered abnormal.

Ball Filling Strategies

For ball mills and stirred mills, it's common practice to use several types of grinding media, such as zirconia balls. To achieve coarse grinding, larger balls are employed, while finer grinding requires smaller ones.

Under normal conditions of current, filling rate, flow rate, and temperature, it's essential to avoid haphazardly adding grinding media. Calculate the daily wear rate of zirconia balls based on the daily production quantity and add a fixed quantity of zirconia balls daily. This practice significantly contributes to the stability and assurance of ultrafine production.

In conclusion, wet ultrafine grinding is a complex process that demands careful consideration of particle size distribution, temperature control, and dispersion agent management. Monitoring key metrics such as fill rate, current, temperature, and flow rate is vital to ensure the effectiveness and stability of the ultrafine grinding process. Additionally, adopting controlled strategies for adding grinding media, like zirconia balls, can play a pivotal role in maintaining a consistent and reliable production output.