Disc Granulators: Why Are They So Popular with Fertilizer Plants?

Among the equipment used to produce organic fertilizer granules, disc granulators, with their smooth, round granules and flexible operation, have become a regular fixture in small and medium-sized fertilizer plants abroad. Their consistent production of high-quality granules relies on seamless collaboration with other fertilizer equipment, ensuring efficiency and peace of mind at every step. Raw material preparation before granulation relies on pretreatment equipment. Composted organic fertilizer powder often contains small impurities, so a vibration screener machine is used to sieve it, leaving a fine, uniform powder. If the powder is too moist, a screw conveyor sprays an appropriate amount of water during delivery.Humidity is controlled at 30%-40%—this "golden ratio" allows the disc granulator to easily granulate the powder. If compound fertilizer is being produced, a horizontal mixer is used to horizontal mixer the organic fertilizer with nitrogen, phosphorus, potassium, and other raw materials to ensure uniform nutrient distribution. In the core granulation process, the disc granulator acts like a "precision dough kneader." The disc, tilted 30°-45°, rotates at 20-30 revolutions per minute. Powder is added at the center of the disc and is continuously lifted and lowered as it rotates. Simultaneously, a spray system precisely applies a small amount of binder, gradually agglomerating the powder into small particles that then grow to 2-5 mm in size.Compared to other granulators, disc granulators produce smooth, rounded granules of uniform size. Furthermore, granule size can be quickly adjusted by adjusting the disc's rotation speed or tilt angle. This makes it particularly suitable for small-batch fertilizer production with multiple specifications, making it particularly useful for small foreign manufacturers that need to flexibly respond to market demand. Newly produced granules are still moist and require drying equipment to "set" them. A mesh belt dryer uses hot air at 60-70°C to gently dry the granules, ensuring the granules meet the required hardness without damaging the active ingredients in the organic fertilizer. The dried granules are then screened by a grading and screening machine, and unqualified granules are returned to the raw material bin for re-granulation, eliminating waste.