1. Hardware Solutions (Equipment Upgrades)

Install Rubber Liners: This is the most effective solution. High-strength flexible rubber plates are bolted inside the drum. As the drum rotates, the rubber deforms slightly due to gravity, causing the sticking material to flake off automatically (Self-cleaning effect).

Mechanical Scrapers: Use adjustable alloy scrapers or cleaning blades to physically remove buildup from the inner walls during rotation.

Pneumatic Hammers: Install air hammers on the exterior of the drum shell. The timed impact vibrations loosen any hardened “crust” forming inside.

EMCC Rotary Drum Granulator

2. Process Optimization (Moisture & Temperature)

Control Liquid Phase: Caking is often caused by excessive moisture. Reduce the steam injection or water spray volume. The material should feel like “damp soil”—cohesive but not muddy.

Increase Recycle Ratio: Add more dry return material (fines and crushed oversize). This absorbs excess surface moisture from the fresh feed and reduces the overall stickiness of the rolling bed.

Temperature Management: If using steam granulation, ensure the temperature is not so high that the material enters a semi-molten state. Keep the discharge temperature stable.

3. Operational Adjustments

Adjust Rotation Speed (RPM): If the speed is too low, material stays at the bottom too long and clumps. Use a Frequency Inverter (VFD) to find the “sweet spot” where the material forms a perfect rolling curtain.

Drum Inclination: Ensure the tilt angle is between 2°-5°. If the angle is too flat, the retention time is too long, leading to over-agglomeration and buildup.

4. Post-Production Prevention

Cooling System: Ensure the granules are cooled to below 40°C in the Rotary Cooler before packaging. Hot granules in a bag will release moisture vapor, which condenses and causes “bag caking.”

Coating Agent: Use a Coating Machine to apply anti-caking oils or powders (like talc or kaolin) to the surface of the finished granules.

Troubleshooting Checklist