Choose a suitable organic fertilizer granulator according to specific process requirements. There are many types of granulators, such as double roller press granulator, disc granulator, rotary drum granulator, etc. For those with strict particle size control, it is recommended to use a roller extrusion granulator, and for those with general requirements for particle size and larger output, it is recommended to use a drum granulator for organic fertilizers.
Basically all granulation drying processes can be granulated with a double roller press granulator. In particular, the particle size of the raw material powder is less than 2 mm, preferably less than 1 mm, which is very suitable for extrusion granulation. Crushed stone, powder, crystalline, granular and pellet raw materials are suitable. For potassium chloride, lower cost standard grades and by-products or products too fine to mix are suitable for extrusion. Although granular urea can be used, powdered or crystalline urea of very small size is more suitable. In some cases, the particle size of the raw material varies so much that larger particles should be broken up first, resulting in a more even distribution of nutrients in the product. The smaller the particle size of the raw material, the less separation of components in the extruded mass during the pulverization process. The purpose of granulation by roller extrusion granulator is to obtain fertilizer granules with highly uniform nutrients.
At present, the compound fertilizer mixing method of the double roller press granulator is developing rapidly both in foreign countries and in China. The quality advantages of large-grained urea, ammonium phosphate and potassium chloride as the basic fertilizers have laid a solid foundation for the blending method. Large quantities of low-cost monoammonium phosphate and diammonium phosphate granular fertilizers, their good storage and transportation properties, suitable low nitrogen and high phosphorus components and compatibility with other blending materials provide favorable conditions for the development of blended fertilizers.