How to optimize rotary drum granulator parameters for better particle uniformity?

In organic or compound fertilizer production, the particle uniformity from rotary drum granulators directly impacts product quality. Here are practical ways to optimize rotary drum granulator settings for more consistent granules:

1. Adjust Rotation Speed

The drum’s rotation speed is critical. Too fast, and materials get thrown out before forming proper granules. Too slow, mixing and agglomeration becomes inefficient. It often takes multiple tests to find the right speed range for your materials. For example, start testing within 8-12 revolutions per minute (RPM) and adjust based on material behavior and granule requirements.

2. Control Filling Rate  

A proper filling rate ensures materials have enough space to tumble and bond. Overfilling (above 30%) causes irregular shapes and uneven sizes due to crowding. Underfilling (below 20%) reduces efficiency. Keep the filling rate between 20% and 30%, tweaking it slightly based on material texture and target granule size.

3. Fine-Tune Spray Volume and Angle  

When using spray binding, too little spray fails to form smooth granules, while too much creates oversized or clumped particles. The spray angle must cover materials evenly as they move inside the drum. Adjust spray volume and angle precisely based on material absorption and movement inside the drum.

4. Material Mix Ratio and Moisture  

Ensure the raw material blend is balanced before granulation. Imbalanced ratios disrupt particle formation. Initial moisture content also matters: overly dry materials won’t bind, while overly wet ones form lumps.

By optimizing these rotary drum granulator parameters, the particle uniformity can be effectively improved, thereby improving product quality and market competitiveness.