Granular fertilizer production technology

Flat die extruder is an important machine for organic fertilizer production. It uses extrusion for granulation, which plays an important role in fertilizer manufacturing technology. In our usual production activities, the methods of fertilizer granulation are various. To help you better understand the process of extrusion granulation, the main methods of extrusion granulation are explained below.

The flat die extruder uses pressure to gather solid materials, and then extrudes the material through rollers, which are driven by eccentric casing or hydraulic system. When extruding the solid material, the air between the powder particles is removed first, and the particles are rearranged to eliminate the gap between the materials.

The extruding granulator shall prevent the powder material from being in the extrusion granulation equipment, and then use external force to compress the powder material tightly. Due to the different ways of using external forces, molecules are reassembled, resulting in cylindrical particles. In the chemical fertilizer manufacturing technology, the whole process of production and extrusion is mechanical operation, without manual operation. Compared with stirring granulation, the shape of material is mainly made by stirring method, which is round.

Flat die extruder granulator

Double roller granulator is also used for extrusion granulation. It is commonly used in fertilizer manufacturing processes, such as compound fertilizers. The thickness of the large plate produced by the roller granulator is 5-20 mm, and the surface density is 1.5-3 times of the feed. Large plates are peeled, crushed and screened to obtain the desired granular products. The pressure formed particles form a hot spot at the contact point and melt the material. When the temperature drops, the material is cooled to form a fixed bridge.

The above is a detailed introduction of extrusion granulation method, which can help us to know more about it, so as to produce qualified granules in fertilizer production. There are many granulation methods in fertilizer processing technology, extrusion granulation is a common method.

Pan Granulation Technology

As a fertilizer granulator which has been used for a long time in chemical fertilizer plant, pan granulator has its unique advantages. In the production of fertilizer granulation, the following factors exist in the particle uniformity.

Structure of pan pan granulator

The disc granulator adopts the whole arc structure, which effectively improves the granulation rate. Combined with non power scraper equipment, it can reduce the accumulation of materials in the granulation process and maximize the use of raw materials. In order to facilitate the flexibility and flexibility of field use, the base is firmly thickened and weighted, without the need for additional anchor screws to fix, which also helps to prevent chassis deformation. The disc granulator is very suitable for field operation, reduces the tedious installation and layout procedures, saves time and improves the work efficiency.

In the granulation stage of NPK fertilizer production line, with the continuous addition of raw materials, under the action of centrifugal force, the manufactured particles fall into the lower belt conveyor through the edge of the plate.

Pan fertilizer granulator

Elements of Pan fertilizer granulator

When the plate granulator processes raw materials, many parameters affect each other. For example, the smaller the diameter of the pelletizing disk is, the lower the disk height is, the larger the inclination angle of the disk is, and the higher the rotation speed is; if the disk height is increased, the inclination angle and rotation speed are higher. The smaller the tilt, the lower the speed.

As a NPK compound fertilizer production equipment, another factor affecting the disc granulator is the tilt angle of the disc. The angle of inclination should not be less than 35 ° during granulation, otherwise the material will stick to the disc and rotate with the disc body. With the increase of inclination angle and rotation speed, the material can avoid accumulating in the lower part without falling and rolling up and down.  More info on pan granulation process, go here with the link.

However, the larger the inclination angle is, the faster the downward rolling speed is, and the smaller the overflow particles are. The most suitable slant point of the disk is related to the diameter of the disk, that is, the slope of the disk decreases with the increase of the disk diameter. 

This is because the end velocity of particles moving along the disk surface increases as the disk diameter increases. In order to avoid the impact and fracture of other particles when the particles are down, the tilt of the disk must be reduced.