There are two kinds of granulation processes for granular fertilizer such as organic fertilizer and compound fertilizer: one is the extrusion granulation process developed from feed granulation (common granulation equipment includes roller granulator and flat die pellet mill). The other is the wet granulation process (the typical granulation equipment includes disc pan granulator and roatary drum granulator). The particles produced by the extrusion granulator are elliptical or cylindrical, and the particles produced by the wet granulation process are spherical and of different sizes.
As a fertilizer processing unit, the quality of production equipment and the advanced degree of production technology are the reliable guarantee of production efficiency and products. However, production safety is the lifeblood of any enterprise. Only the safety production order can realize the three principles of quality, efficiency and development.
Raw materials for wet granulation
In the production of compound fertilizer, the basic raw materials, such as nitrogen, phosphorus and potassium, or their solutions and molten slurry, are mixed in a certain proportion, and then the finished granular compound fertilizer is obtained through granulation, drying, cooling and screening. Due to the different physical and chemical properties of raw materials, there is a large number of solid material flow in the production process, involving more mechanical transmission and conveying equipment. Urea and compound fertilizer have certain thermal decomposition properties, as well as a large number of gas dust spillage, so it is necessary to fully understand its safety characteristics.
Machinery for wet granulation
- Disc granulator machine: the rotation of the disc body makes the materials adhere to each other to form small balls. Due to the difference of particle mass, the gravity and centrifugal effect are also different. When the gravity and centrifugal effect increase enough to overcome the friction between particles, they will be thrown out of the disk, and the smaller particles will remain in the disk to continue to gather fine particles.
- Rotary drum granulator: This machine is suitable for the production and processing of NPK compound fertilizer with large output and similar principle. Different from the traditional granulation process, the inner lining of the rotary granulator provided by us is unique. When the cylinder is turned from the bottom to the top, the inner lining will sag due to the self weight, and the materials attached to the inner lining will fall down due to the gravity, so as to achieve the function of automatic cleaning and caking.