NPK Fertilizer Rotary drum granulation is one of the most widely used traditional processes in NPK compound fertilizer production. It relies on the mechanical rolling of a rotating drum and the frictional bonding principle of materials to complete granulation. With its strong adaptability and stable production capacity, it has become the mainstream production process for small and medium-sized fertilizer enterprises and occupies an important position in fertilizer industrial production. This process has distinct characteristics, possessing both significant advantages and unavoidable shortcomings, which have a profound impact on product quality and production efficiency.

The core advantages of the rotary drum granulation process lie in its production stability and practicality. First, the equipment has a simple structure, low failure rate, and convenient operation and maintenance. It requires less technical expertise from production personnel, is suitable for large-scale, continuous industrial production, and its single-machine capacity is far higher than that of disc granulation, meeting the needs of large-volume NPK fertilizer production. Second, it has extremely strong raw material adaptability, compatible with various conventional nitrogen, phosphorus, and potassium raw materials such as urea, monoammonium phosphate, and potassium chloride. It can also add trace elements and organic matter additives, allowing for flexible formula adjustments and the production of general-purpose compound fertilizers with various ratios. Furthermore, the process is mature, with low production costs, controllable energy consumption during granulation, and finished granules with moderate hardness that are not easily broken, resulting in low losses during subsequent storage and transportation.
However, this process also has significant shortcomings that restrict the production of high-end fertilizers. Firstly, granulation uniformity is poor; relying on physical rolling molding, granules are of inconsistent size, requiring multiple screening processes and resulting in a high waste recovery rate. Secondly, it is highly sensitive to production parameters; slight deviations in material moisture content, drum speed, and temperature can lead to decreased granulation rate, material sticking to the walls, and clumping, affecting production efficiency. Thirdly, the nutrient uniformity of the product is generally lower; compared to spray granulation, the nutrient deviation between granules is slightly larger, making it difficult to meet the high-precision, high-stability requirements of high-end agricultural fertilization. Finally, the production process generates more dust, resulting in relatively higher material losses and greater environmental protection challenges.
Overall, the drum granulation process offers high cost-effectiveness and practicality, suitable for mass-market, large-scale NPK fertilizer production, but it has shortcomings in product precision and environmental performance. In production, defects can be made up by optimizing operating parameters and using fine screening and dust removal equipment, so that traditional processes can be better adapted to the needs of modern agricultural production.