In mineral processing production, when the grinding fineness fluctuates, operators often encounter a question: Should the feed rate be adjusted first, or the water addition rate?

The key is not which one to adjust first as a fixed rule, but to first determine the cause of the fluctuation.

1. If the mill load is high, check the feed rate first
When the feed rate is too high, the ore hardness increases, or the mill load continues to rise, the grinding capacity may not keep up with the changes in the feed. At this time, the feed rate, mill load, and circulating load (return sand) should be checked, and the feed rate should be adjusted smoothly according to process requirements if necessary.

2. If the pulp density is abnormal, focus on checking the water addition
The water addition rate affects the pulp density, flow state, and classification process. If the density is too high or too low, it may affect the grinding and cyclone classification performance.

However, more water is not always better; it should be adjusted in combination with the density, flow rate, and cyclone operating status.

3. If both parameters are normal, what else should be checked?
The grinding ball size distribution (ball charge grading), ore properties, cyclone pressure, underflow state, and the reliability of particle size detection should also be checked. Fluctuations in grinding fineness are often caused by multiple factors working together.

How does automation coordinate with this?
The PLC/DCS can monitor the feed rate, mill load, water addition flow rate, pump sump level, and cyclone pressure to help identify abnormal trends, and then coordinate adjustments according to process logic.