Roll squeezing granulator is a granulation equipment widely used in industries such as chemical, pharmaceutical, food, and fertilizer, especially in the production line of NPK fertilizer (nitrogen phosphorus potassium compound fertilizer), which plays a crucial role. Below is a detailed explanation of its working principle and granulation advantages:

working principle

The roller extrusion granulator is mainly based on two high-strength metal rollers placed in parallel and rotating relative to each other to carry out granulation. These two rollers are engraved with specific patterns or grooves on their surfaces to increase the friction between the material and the roller contact surface. During work, powdered raw materials that have been pre wetted to the appropriate moisture content are fed into the space between two rollers through the feeding port. Due to the squeezing effect of the drum, the raw material is compressed and passes through the gap between the drums, forming a continuous strip like material. Afterwards, these strip-shaped materials will be placed in a granulator or directly dropped into the cutting device below, forming the final desired particle shape through cutting action.

To ensure the granulation effect, the pressure, temperature, and moisture content of the material need to be precisely controlled throughout the entire process. The correct parameter settings can ensure that the density of the material is moderate, neither causing the particles to become too hard and difficult to dissolve due to excessive pressure, nor causing the particles to become too loose and lose shape due to insufficient pressure.

Granulation advantages

High flexibility: The roller extrusion granulator can adjust the pressure and speed of the drum according to different raw material characteristics and target particle sizes, with a wide range of applications.

Excellent particle strength: Through precise rolling, solid and uniform particles can be obtained, which are not easily broken even during transportation and storage, improving logistics efficiency.

Uniformity: Thanks to the design of the drum surface, all particles undergo a similar pressurization process, ensuring consistent size and shape, which is crucial for manual sowing and machine fertilization.

Economical and efficient: compared with the traditional spray drying method, the roller extrusion granulator has lower energy consumption and lower operating costs, especially in large-scale production.

Easy to clean and maintain: Due to its simple structural design, daily cleaning and maintenance work is easy, downtime is short, and production efficiency is improved.

Environmental Protection: During the granulation process, there is no need to add additional adhesives, reducing environmental pollution, and the granulation process itself produces almost no wastewater or exhaust gas.

The roller extrusion granulator, with its advanced technology and outstanding performance, has become the core equipment in NPK fertilizer production lines, providing strong support for modern industrial production and agricultural development.