What is Organic Fertilizer Dry Granulation?

Organic fertilizer dry granulation of is a technical approach that directly compresses fermented powdered organic raw materials into granules without adding water or drying. Its core equipment is a flat die press granualtor or a roller press granualtor. Using mechanical pressure (20–50 MPa), materials with a moisture content of 15%–25% are forced through die holes or roller gaps, instantly forming and cutting to obtain cylindrical or oblate spherical granules with a diameter of 2–8 mm. Because no drying is required, there is no waste gas or wastewater emission, and energy consumption is reduced by 30%–50% compared to traditional wet processes (disc/drum). A single machine can produce 1–5 tons per hour. Dry granules have high immediate hardness (≥10 N), allowing for immediate screening and packaging, making them suitable for heat-sensitive materials such as organic-inorganic compound fertilizers, carbon-based fertilizers, and microbial fertilizers.

In actual production, to ensure the stability and quality of dry granulation, precise control of the physical properties of the raw materials is necessary. For example, controlling the particle size distribution within a reasonable range is crucial to avoid die blockage due to overly coarse particles or excessive dust due to overly fine particles. Simultaneously, the mechanical pressure parameters during the organic fertilizer dry granulator process of need to be dynamically adjusted according to the proportions and characteristics of different raw materials. For instance, for materials with high fiber content, the pressure can be appropriately increased to enhance particle density; while for materials with high viscosity, the pressure needs to be reduced to prevent excessive particle adhesion. Furthermore, the dry granulation process places extremely high demands on the precision of the granulation equipment's molds. The shape, diameter, and surface smoothness of the mold holes directly affect the granulation rate and appearance. Therefore, the molds must be made of wear-resistant materials and undergo regular inspection and maintenance to extend their service life and ensure consistent granulation results.