2025/11/27
NPK fertilizer production involves scientifically proportioning the three essential nutrients—Nitrogen (N), Phosphorus (P), and Potassium (K)—and processing them through a series of physical and chemical steps to create compound fertilizers. The typical npk fertilizer manufacturing process includes the following key stages:
Raw Material Handling Section: First, basic raw materials such as urea, ammonium chloride, monoammonium phosphate, and potassium chloride are crushed and screened to ensure particle size meets granulation requirements. Key equipment in this stage includes chain crushers, rotary screening machines, and conveyor systems.
Batching and Mixing System: According to the target formula, raw materials are precisely proportioned using electronic belt scales and metering devices, then fed into double axis mixers for uniform blending. Modern plants commonly use DCS automation control systems to ensure accurate proportioning.
Granulation Process: The mixed materials are fed into a rotary drum granulator or disc granulator, where they form uniform particles under the action of steam and binders. The rotary drum granulator, which forms pellets through rotational motion, is currently the mainstream granulation equipment.
Drying and Cooling: The wet granules enter a rotary dryer, where they contact high-temperature flue gas from a hot air furnace to remove moisture. They are then cooled in a rotary cooler to prevent caking and maintain product stability.
Screening and Coating: After cooling, the particles are graded by vibrating screens. Qualified products are sent to a coating machine for application of anti-caking agents, while non-conforming particles are returned for crushing and reuse. Exhaust gases are treated through cyclone dust collectors and wet scrubbers to meet emission standards.
II. Supporting Equipment Systems
A complete production line also requires:
1. Heating system: Gas-fired hot air furnace or steam boiler
2. Environmental protection equipment: Bag dust collectors, acid scrubbers, desulfurization units
3. Automated packaging line: Automatic quantitative packaging machines, bag sewing machines, and palletizing robots
4. Auxiliary facilities: Raw material warehouse, finished product warehouse, laboratory testing center
Modern NPK fertilizer plants integrate PLC control systems to achieve fully automated production from raw material feeding to finished product packaging. This not only ensures accurate nutrient content but also significantly improves energy efficiency and environmental performance.