Flat die pelleting machines, double roller press granulators, and rotary drum granulators are the mainstream granulation equipment in fertilizer production. These three types differ significantly in core dimensions such as molding principle, raw material suitability, and production capacity and quality. Choosing the right equipment requires considering production scale, raw material characteristics, and product requirements.

Molding Principle and Raw Material Suitability: Flat die pelleting machines form granules through mold extrusion, suitable for both wet and dry raw materials, especially suitable for organic fertilizers and NPK compound fertilizers with moderate viscosity, and have low requirements for raw material particle size; double roller press granulators use double rollers to extrude dry materials for granulation, requiring no water addition, suitable for low-viscosity dry powder raw materials, and can save the drying process; rotary drum granulators form granules through drum rolling and spraying conditioning, more suitable for high-humidity, easily agglomerating fermented organic fertilizer raw materials.

In terms of production capacity and quality, flat die pelleting machines have medium production capacity, suitable for small and medium-scale production, producing granules with high strength and uniform particle size, but the molds are easily damaged; double roller press granulators have adjustable production capacity, suitable for small and medium-scale production, producing granules with high strength and high molding rate, but the shape is less regular; rotary drum granulators have large production capacity, suitable for large-scale continuous production, producing granules with good roundness and excellent appearance, but the strength is low and prone to pulverization.

Selection Suggestions: For small and medium-scale production, prioritizing granule strength and adaptability to multiple raw materials, choose a flat die pelleting machine; for dry material granulation, needing to save on drying costs, and prioritizing hardness, a double roller press granulator is preferred; for large-scale continuous production, focusing on granule appearance, a rotary drum granulator is more suitable.