In fertilizer manufacturing, granule hardness and uniformity directly affect the product’s storage stability, transport resistance, and application efficiency. When using a roller press granulator—also known as a dry granulation compactor or double roller extrusion granulator—controlling granule strength becomes a key technical goal.
1. Optimize Raw Material Moisture and Fineness
One of the primary factors influencing granule strength is the moisture content of the powder material. In general, raw materials with 1–3% moisture perform best during compaction. Too much water can cause sticking on the rollers, while too little leads to weak bonding between particles.
Additionally, the particle size distribution should be well-balanced. A combination of fine and slightly coarse powder helps fill internal voids during extrusion, forming denser and stronger granules.
2. Adjust Roller Pressure and Gap Settings
The roller pressure directly determines the compacting force applied to the materials. Higher pressure usually results in higher granule strength, but excessive force can damage the surface structure or wear the rollers prematurely.
Operators should also monitor the roller gap—the distance between the two pressing rollers. A smaller gap increases density, while a slightly wider gap can prevent over-compression and cracking. Most production lines rely on pressure sensors or hydraulic systems for precise adjustment.
3. Improve Binder Formulation
For materials with poor cohesiveness, adding a binder or auxiliary agent can greatly enhance granule integrity. Common binders include lignin sulfonate, molasses, starch, or bentonite. These additives promote better adhesion among particles without significantly changing the nutrient content of the fertilizer.
4. Maintain Consistent Feeding and Rolling Speed
Uneven feeding leads to irregular granule density. Using a screw feeder or automatic dosing system ensures uniform material supply to the rollers. Likewise, controlling the roller rotation speed prevents excessive vibration and improves compression stability.
5. Use Reliable Post-Treatment Equipment
After compaction, the flakes are crushed and screened. At this stage, over-crushing may reduce granule size and weaken strength. Incorporating a precision crusher, automatic sieving system, and gentle polishing drum helps retain granule quality while achieving uniform size distribution. Learn more!
Final Thoughts
Enhancing the strength of granules in a roller compactor granulation process depends on the balance between raw material characteristics, mechanical force, and binder formulation. A well-calibrated system can reduce dust generation, improve fertilizer appearance, and lower production costs in the long run. If you want to invest the machine, you can visit: https://www.biofertilizerproduction.com/product/roller-compactor-granulator-for-bio-fertilizer-manufacturing/