How should a granulator choose a granulation method during granulation?

1. Material characteristics: whether the material is in powder or molten form, whether slurry and paste materials can be pumped and atomized, whether the material has thermal sensitivity, etc., must be considered when selecting.

2. Requirements for particle size and particle size distribution of agglomerates: some methods, such as spray drying granulation, can only obtain very fine particles, and the method of agglomerating the powder can only obtain smaller particles, while other methods, such as pressing, can obtain large agglomerates.

3. The shape of agglomerates: Rolling, stirring, and spraying result in approximately spherical particles; Shot peening cooling solidification granulation can obtain completely spherical particles; Squeezing granulation can produce column pellets. The possible impact of particles of different shapes on subsequent work should be estimated.

4. Strength of agglomerates: Particles obtained from powder agglomeration and shot peening have weaker mechanical strength. If high-strength particles are required, compression methods or sintering and calcination strengthening should be used, and high-strength binders should be selected for extrusion molding.

5. The porosity and density of agglomerates are closely related to strength, and some extrusion granulation processes can better control the porosity and density to meet certain application needs.

6. Wet and dry methods: Wet granulation requires expensive solvents, and drying after taking the medicine may cause solvent loss. Some materials may be sensitive to solvents and not suitable for wet methods, while others may recrystallize into different shapes during drying and cannot be used with wet methods; Dry granulation is prone to producing powder and is not suitable for handling toxic chemicals and other hazardous materials.

At least two different granulation methods can be initially selected during the selection process, and further detailed considerations can be made through experiments. Consider whether the reliability and flexibility of the equipment are easy to manufacture and maintain, and make the final choice based on the principle of minimizing the total cost under the required output.