What is the core function of a rotary film coating machine for organic fertilizer? What production pain points can it address?
The core function of a rotary film coating machine for organic fertilizer is to evenly coat the surface of organic fertilizer granules with a functional film. The film material can be selected according to needs (such as anti-caking agents, slow-release agents, trace elements, water-retaining agents, etc.). It can address three major production pain points: First, it prevents the finished organic fertilizer from clumping due to moisture absorption during storage and transportation, ensuring the looseness of the granules. Second, by coating with a slow-release film, the fertilizer's nutrient release cycle is extended, improving the fertilizer's long-term effectiveness. Third, it reduces dust generated during application, minimizing nutrient loss and preventing soil and environmental pollution.
"How can the coating effect be ensured to be uniform?"
High-quality rotary film coating machines ensure coating uniformity through three key design features: First, they utilize an inclined rotary drum, which rotates as the granules within the drum, creating a "tumbling-sliding-tumbling" cycle, which circulates with the coating liquid. The first is to ensure full contact between the pellets and the powder; the second is to equip the drum with multiple atomizing nozzles to evenly spray (or spread) the coating agent onto the pellet surface; the third is to install a lifting plate inside the drum to lift the pellets upward and evenly distribute them to avoid localized accumulation.
What factors affect coating quality?
There are four key factors affecting coating quality: ① Coating agent concentration (a high concentration can cause pellets to stick together, while a low concentration can result in an incomplete coating layer); ② Drum speed (a high speed can cause coating agent splashing, while a slow speed can result in uneven mixing of the pellets); ③ Feed rate (must match the equipment's processing capacity; overloading can result in insufficient pellet residence time in the drum, resulting in incomplete coating); and ④ Particle humidity (high humidity can lead to poor coating agent adhesion and easy peeling of the coating layer).
What particle size of organic fertilizer pellets can the equipment process? Is there a requirement for pellet hardness?
The organic fertilizer rotary coating machine is highly adaptable to particle sizes, processing 0.5-8mm. Organic fertilizer granules include common forms such as conventional powdered organic fertilizer (which requires granulation), columnar organic fertilizer, and pelletized organic fertilizer.
Pellets have a basic hardness requirement: the compressive strength must be ≥2N to prevent breakage due to impact during tumbling. If the granules are not sufficiently hard (such as wet granules from fresh granulation), it is recommended to dry and cool them before coating them. This prevents broken granules from mixing with the coating agent and forming clumps, which could affect the final coating effect.
