NPK fertilizer is an indispensable source of nutrient supply in modern agriculture. It occupies a pivotal position in the agricultural field, and its production line process is worth in-depth exploration. Generally speaking, granulation is the main process of making granular fertilizer. Therefore, the process flow of  NPK fertilizer production line can be divided into 3 parts: mixing before granulation, granulation, and process after granulation.

1. Mixing stage

Raw material preparation: Various raw materials containing nitrogen, phosphorus and potassium are delivered to the production line. These raw materials come from a wide range of sources and their quality must be ensured. Before entering the production line, the raw materials must be initially tested to ensure that they meet production requirements.

Batching stage: Based on the target NPK ratio, each raw material is accurately weighed by high-precision batching equipment. Then the weighed raw materials are placed in a Mixer (such as Horizontal Mixer, BB Fertilizer Mixer) to thoroughly mix the various raw materials. This ensures that every tiny portion of fertilizer contains the right proportion of nitrogen, phosphorus and potassium elements.

2. Granulation stage

Dry granulation: Dry granulation (such as Double Roller Press Granulator) is used to directly press the dry material into granules through physical extrusion, compression, etc., retaining the original nutrients and physical properties of the material.

Wet granulation: Wet granulation (such as Rotary Drum Granulator, Disc Granulator) is used to add an appropriate amount of wetting agent or adhesive to the material, and the material undergoes a chemical reaction in the cylinder to form granules under the action of pressure.

3. Post-granulation process

Drying and cooling: Dryers and coolers are used to make the granules better. If the granules are not dried and cooled after granulation, the temperature and moisture content of the granules will be too high, and mold and agglomeration will occur, which is not conducive to storage. If a Double Roller Press Granulator is used for granulation, drying and cooling are not required.

Screening: The dried and cooled granules are screened by a screening machine (such as Drum Screener Machine, Vibration Screener Machine) to separate qualified granules from unqualified granules. Qualified granules enter the next process, and unqualified granules are returned for re-granulation to achieve resource recycling.

Coating: Using a Coating Machine to coat the fertilizer granules can make the granules smoother and more convenient to transport. At the same time, coating can prevent the agglomeration of nitrogen, phosphorus and potassium fertilizers.

Packing: The final product is packed by an automatic Packing Machine according to specifications, and the particle strength and nutrient errors are simultaneously detected to ensure that the quality meets the standards.

The NPK fertilizer production line takes into account both production efficiency and environmental protection needs through scientific proportioning, multi-stage drying and intelligent control. Whether it is the mature granulation process or the adoption of other processes, precision and greenness are the core goals, providing reliable support for the sustainable development of global agriculture.