Wet-granulation

Introduction to wet granulation process

Wet granulation is a process that combines powdered materials with appropriate liquid wetting agents to form granules. Common wetting agents include solvents such as water and ethanol, or adhesive solutions formulated in specific ratios. This technology is widely used in pharmaceuticals, food processing, and related industries. It aims to improve material flowability, reduce dust generation, enhance mixing uniformity, and provide suitable granular forms for subsequent tablet compression or filling processes.

Principle of the device

Wet pelletization is usually carried out by high speed mixer granulator, which mainly consists of:

· Pot: used to contain materials and wetting agents.

· Stirring paddle: generate shear force through rotation to promote material mixing and particle formation.

· Cutting knife: used to cut wet material into uniform particles.

During operation, the material and wetting agent are thoroughly mixed in the pot to form a moist, soft material. The cutting blade then cuts it into particles of the desired size.

Process characteristics

· Improve fluidity: Through granulation, the fluidity of powder material is significantly improved, which is convenient for subsequent processing.

· Reduce dust: wet granulation effectively reduces the production of dust and improves the working environment.

· Improve mixing uniformity: the material is more uniform when wet, ensuring consistency of components.

· Particle control: The particle size and morphology can be controlled by adjusting the process parameters to meet the needs of different products.

Key control parameters

1. Wetting agent dosage: the amount of wetting agent added directly affects the degree of moisture and adhesion of particles. Too much may lead to excessive moisture of particles, too little may lead to insufficient adhesion of particles.

2. Agitator speed: the speed of the agitator affects the shear force, which in turn affects the formation and particle size distribution of particles.

3. Cutting blade speed: the cutting blade speed determines the cutting speed and particle size of particles.

4. Granulation time: too short granulation time may lead to uneven granules, too long granulation time may lead to excessive growth or adhesion of granules.

5. Material loading capacity: too much loading may lead to uneven mixing, too little may affect production efficiency.

In the process development and scale-up process, the above parameters need to be optimized according to the specific material and equipment characteristics to ensure particle quality and production efficiency.