To maintain the physical properties of granular fertilizer produced by rotary drum granulators during storage, the following measures should be taken:
1. Storage Temperature
Keep storage temperatures relatively low, ideally below 35–40°C, and never exceeding 45°C. High temperatures can cause the fertilizer to absorb moisture and clump together, damaging its physical quality.
2. Humidity Control
The hygroscopicity of granules produced by fertilizer granulators is an important factor affecting their physical properties. Store the product in a dry environment with low humidity to prevent clumping. Different fertilizers have varying moisture absorption thresholds. For example, calcium nitrate and ammonium nitrate absorb moisture easily (low threshold), while ammonium sulfate, superphosphate, and potassium sulfate are less prone (higher threshold).
3. Storage Duration
Different fertilizers have distinct shelf lives. Urea can be stored long-term in cool, dry conditions but loses weight if damp. Ammonium bicarbonate remains stable in cool, ventilated areas but releases ammonia if exposed to heat or moisture. Superphosphate gradually loses effectiveness after six months. Potassium chloride or sulfate are chemically stable and can be stored for extended periods.
4. Packaging and Stacking
Use airtight packaging to limit air exposure. Avoid stacking bags too high or under heavy pressure to prevent crushing the granules. For bulk storage, plan stacking heights carefully and place moisture-proof boards under the piles.
5. Anti-Clumping Measures
Add anti-caking agents during storage to reduce clumping. Regularly inspect the fertilizer and address any clumped or degraded material promptly.
6. Avoid Mixing Incompatible Products
Some fertilizers react chemically when stored together. For instance, mixing ammonium nitrate with urea increases moisture absorption. Always store chemically incompatible fertilizers separately.
Through the above measures, the physical properties of the granular fertilizer produced by the rotary drum granulator can be effectively maintained to ensure its effectiveness during storage and use.
