Double roller press granulators are the core fertilizer production equipment., the double roller press granulator achieves energy-efficient production through dry granulation technology. Its process flow is clear and interconnected, ensuring uniform fertilizer granules and meeting strength standards.

Production begins with raw material pretreatment. Whether it's livestock manure and straw for organic fertilizer or nitrogen, phosphorus, and potassium raw materials for compound fertilizer, all require crushing, mixing, and moisture control. Raw materials must be crushed to below 0.5mm, and after uniform mixing, the moisture content is controlled at 2%-5% (compound fertilizer) or 18%-22% (organic fertilizer) to avoid problems such as sticking to the rollers or excessively low pelleting rate. Precise proportioning through an automatic batching system ensures balanced fertilizer nutrients, laying the foundation for subsequent granulation.
The core granulation process is completed by the double-roller extrusion. The mixed powder is evenly fed into the space between two opposing rotating rollers by a quantitative feeding system. The hydraulic system provides a pressure of 15-25MPa, adjusting the roller gap according to the material characteristics. Under high pressure, molecular attraction forms between material particles, compressing them into dense, sheet-like or spherical intermediates. Once the pressure reaches its peak, it is rapidly released, and the intermediates detach from the roller surface due to rebound force. The die design of the roller surface directly determines the shape and specifications of the finished granules, allowing for the production of fertilizers with different particle sizes from 2.5 to 30 mm.
Post-processing ensures product quality. The compressed granules are broken down by a crushing device and then graded by a drum screener machine. Large, unqualified particles are crushed and returned to the granulator, while fine powder is re-mixed and pre-treated, achieving raw material recycling. This dry process, eliminating the need for drying, reduces energy consumption and prevents nutrient loss. Qualified granules, after cooling, are weighed and packaged by an automatic packaging scale, completing the entire production process.
This short, environmentally friendly, and energy-saving fertilizer granulator is suitable for the production of various fertilizers, including organic and compound fertilizers. Furthermore, parameter control ensures product stability, making it a preferred solution for modern agricultural fertilizer processing.