Both rotary drum granulators and roller extrusion granulators have their own advantages in fertilizer production, and they have significant differences in multiple dimensions.
In terms of working principle, the rotary drum granulator uses a rotating drum to lift up the material internally. Under the action of centrifugal force, friction force, and gravity, the material circulates and the binder is sprayed to form the particles. The counter roll extrusion granulator uses a pair of rotating rollers to squeeze the material into the concave mold on the surface of the rollers, without the need for adhesive (which can be added in some cases).
In terms of particle characteristics, the shape of the particles produced by the rotary drum granulator is relatively regular, mostly approximately spherical or elliptical, and the surface of the particles is relatively smooth. Due to the sufficient rolling of the material inside the drum, the internal structure of the particles is relatively uniform. The particle shape produced by the roller extrusion granulator depends on the shape of the die and can be customized in various shapes, such as square, cylindrical, etc. High particle density and strength, suitable for occasions with high requirements for particle strength.
In terms of production efficiency, the rotary drum granulator has high production efficiency. The continuous rotation and large capacity of the rotary drum can achieve rapid processing of large amounts of materials, making it suitable for large-scale production. The production efficiency of the roller extrusion granulator is relatively low, the extrusion process of the rollers is relatively slow, and the processing capacity is limited by the size of the rollers, making it more suitable for small and medium-sized production or production with special requirements for particle shape.
In terms of raw material adaptability, the rotary drum granulator has a wide range of adaptability to raw materials. Whether it is high viscosity or low viscosity raw materials, granulation can be carried out by adjusting the amount of binder and process parameters. The roller extrusion granulator has strict requirements for the particle size of the raw materials, which need to be uniform and small. It does not require high viscosity, and can even handle non viscous raw materials.
The maintenance and operation costs of the equipment also vary. The structure of the rotary drum granulator is complex, and the internal components such as the plate are prone to wear and tear, making maintenance difficult and operating costs high. The maintenance of the roller extrusion granulator mainly focuses on the maintenance and replacement of the rollers. Although the cost of rollers is high, the overall maintenance is relatively simple and the operating cost is relatively low.
In terms of investment cost, the rotary drum granulator is relatively expensive due to its complex structure and large size. The price of the roller extrusion granulator varies depending on the material and precision of the rolling mill, but overall it may be lower compared to the rotary drum granulator.
Drum granulator and roller extrusion granulator each have their own length. Fertilizer production enterprises should carefully choose suitable granulation equipment based on various factors such as their own production scale, raw material characteristics, product positioning, and cost budget, in order to achieve efficient production and maximize economic benefits.
