In a complete NPK compound fertilizer production line, the rotary drum granulator serves as the core shaping equipment that determines the quality of the final granules. Utilizing a mature wet-agglomeration granulation process, it is widely employed in large- and medium-scale compound fertilizer plants and stands as one of the industry's primary granulation solutions. The rotary drum granulator from Huaqiang Heavy Industry is compatible with various powdered NPK raw materials—such as urea, monoammonium phosphate (MAP), and potassium chloride—allowing for the flexible production of high-, medium-, and low-concentration NPK fertilizers with diverse nutrient ratios. It offers exceptional stability and significant advantages in production capacity.

The rotary drum granulator operates through the continuous rotation of an inclined cylinder, where materials tumble under the influence of gravity, friction, and centrifugal force. A spray system inside the drum introduces steam or slurry; under optimal temperature and humidity conditions, powder particles collide and adhere to one another. Using fine powder particles as nuclei, they gradually grow into uniform, rounded compound fertilizer granules—typically controlled to a size of 2–4 mm, meeting standard market requirements. The steam granulation process raises the temperature of the material bed, facilitating the partial dissolution of salts. This enables efficient granulation at lower moisture levels, which reduces energy consumption during the subsequent drying stage and lowers overall production costs.
The complete NPK production process consists of batching and mixing, rotary drum granulation, drying, cooling, screening, coating, and packaging. The rotary drum granulator bridges the upstream mixing section and the downstream drying section, facilitating continuous operation with stable feeding and smooth discharging. It achieves a high granulation rate, producing granules with excellent sphericity and high compressive strength. These granules are resistant to breakage and caking, making them convenient for storage, transport, and mechanized application. Compared to disc granulators, rotary drum granulators offer higher single-unit capacity, smoother operation, and greater durability—thanks to wear-resistant internal lining plates—while remaining easy to maintain, making them ideal for long-term, continuous production.
This equipment demonstrates strong compatibility with various raw materials; beyond standard NPK fertilizers, it can also incorporate secondary nutrients and trace elements to produce specialized, functional compound fertilizers. The equipment features a simple structure and a low failure rate. It is well-suited for integration into automated systems and can be connected to the centralized control system of an entire production line, thereby reducing the intensity of manual labor.
As the agricultural sector places increasingly high demands on the quality of compound fertilizers, consistent granule uniformity and effective nutrient release have become critical factors for product competitiveness. Leveraging mature technology, stable production capacity, and broad compatibility with various formulations, the rotary drum granulator from Huaqiang Heavy Industry continues to serve as a core component in NPK compound fertilizer production lines. It enables fertilizer manufacturers to consistently produce high-quality granular fertilizers, facilitating large-scale, low-cost production and contributing to the overall improvement of quality and efficiency within the compound fertilizer industry.