Agglomeration granulation refers to the formation of micronuclei in the granulation process of fertilizer granulation machine. Under the action of friction and rolling impact force produced by low-speed rotation of container, the agglomerated micronuclei continuously rotate and grow in the powder layer, and finally become spherical particles of certain size. 1. The effect of moisture
Water is the key factor to form the liquid bridge between the original particles. The pre wetting of powder before agglomeration is helpful to the formation of micronuclei and the quality of granulation. However, the amount of water added in different powder materials and granulation methods is also different, which is generally determined by experiments.

2. The influence of raw material powder
The particle size of powder material is one of the main factors affecting the particle strength, and the particle strength is inversely proportional to the particle diameter of the powder material. Therefore, in the process of granulation, the powder materials need to be crushed.
3. The influence of adhesive
Water is a common cheap binder. The binder plays a role by filling the pores between primary particles and forming a liquid film with strong surface tension. Some binders can also react with the surface of primary particles to form a strong chemical bond. In addition to selecting suitable varieties, attention should also be paid to the amount of binder. Too little does not work, and too much may affect the application performance. For some suitable products, sometimes in order to promote the formation of particles, some fine bentonite powder is added into the raw material powder to improve the granulation strength due to its expansion and good surface wettability when meeting with water.

4. Agglutination state of material particles
The surface of the particles is irregular, and the gap is rough filling structure. Before the granulation of powder material, the shape of powder should be selected to improve the aggregate state of powder, so as to provide suitable conditions for granulation.