The factors affecting the fluidized bed granulation process (Three)

The fluid bed granulation process is a robust process that requires precise and repeatable control of all critical process parameters. Effective and reliable process control tools are required to ensure the quality of the final product.

The factors affecting the fluidized bed granulation process can be divided into three categories: formulation-related variables, equipment-related variables and process-related variables.

Process-related variables: The fluidized bed granulation process is a dynamic process in which mist droplets are generated by a spray gun and deposited on randomly fluidized granules. The adhesive solvent evaporates, leaving the adhesive behind. Other random particles bond in contact with the wet particles until all the solvent has evaporated. This process is repeated several times to produce the desired particles. There are many process variables that control granulation. The most important process variables are: process inlet air temperature, atomization pressure, air fluidization velocity and volume, liquid spray velocity, position and number of spray guns, material temperature and outlet air temperature, filter porosity and reaction Blowing frequency, fluidized bed volume.

These process parameters are interdependent, and if this interdependence can be understood, the desired product can be produced. The inlet air temperature depends on the choice of binder carrier and the heat sensitivity of the particles formed. Generally, the aqueous solution allows the use of the inlet air temperature range of 60°C-100°C. Organic solvents need to use an inlet air temperature of 50°C to below room temperature. Higher inlet air temperature will rapidly evaporate the binder solvent, which will form smaller brittle particles.