In the organic fertilizer production process, the granulator is the core equipment that transforms raw materials from loose powder into regular granules. Its performance directly determines the ease of application, nutrient stability, and storage and transportation properties of the organic fertilizer. In the production of organic fertilizers, the granulation process revolves around three core stages: raw material pretreatment, forced molding, and particle screening, forming a highly efficient granulation system.
Raw material pretreatment is the prerequisite for the efficient operation of the granulator. The fermented and matured organic fertilizer raw materials must first undergo crushing, screening, and moisture adjustment to ensure uniform particle size and a moisture content controlled between 25% and 35%. The qualified raw materials are conveyed to the granulator's feed inlet via a conveying device and uniformly pushed into the granulation chamber by a screw feeding device, preventing material accumulation or uneven feeding that could affect the molding effect.
The granulation chamber is the key area for particle formation. Different types of granulators (such as disc granulators and rotary drum granulators) have slightly different working principles in this stage, but the core logic is "agglomeration under external force." Taking the widely used disc granulator as an example, when the inclined disc rotates at high speed, the raw materials undergo circular motion under the combined action of centrifugal force, friction, and gravity. Simultaneously, a spraying system precisely sprays an appropriate amount of water, causing the raw material particles to gradually adsorb and agglomerate, forming uniformly sized spherical granules.
The formed granules are not directly the finished product. They need to undergo preliminary screening at the discharge port. Unqualified large particles or powder will be returned to the granulation chamber for reprocessing. Qualified granules then enter the subsequent drying and cooling processes, ultimately forming organic fertilizer products that meet the standards. The stable operation of the granulator is not only a crucial step in the organic fertilizer making process but also enhances the commercial value of the organic fertilizer, allowing for a more gradual release of nutrients, meeting the needs of modern precision fertilization, and becoming an indispensable key link in the industrial production of organic fertilizers.
