Wet granulation is a multistage process used for the manufacturing of tablets, capsules and dry powder suspension.
For wet granulation, different types of equipment are used including some manual activities like manual sieving.
All equipment used performs a specific role during the granulation process.
Following is a brief overview of some commonly used equipment,
For Pre Sieving
For pre-sieving, the conventional method is to sieve powders manually using SS sieves which are fitted in a stainless steel frame.To boost the sieving process and to enhance productivity automatic and semi automatic equipment are also used which are given as,
- Oscillating granulator
- Vibro Sifter
- Dry Mill
Oscillating Granulator
Oscillating granulator is the equipment which is used for pre sieving and for this purpose a mesh or sieve is installed in the oscillating granulator.
Different sizes of mesh are used in oscillating granulator as per batch manufacturing record.
Vibratory Sifter
Vibro sifter is also known as Russell sifter and in this sifter, the round shape sieves are installed.
Dry mill
In the dry mill we also have the option to install mesh size as per requirement.
Pre Mixing
Uniform mixing of powders is required before the kneading or wetting step and the following mixers are used
- Double cone blender
- Sigma Mixer/Spiral Mixer/Ribbon Mixer
- Plough mixer
- Bin Blender
- V type blender
- Rapid Mixing granulator(RMG)
For Wetting/Kneading
For kneading or wetting of powders following equipment is used.
Low-shear Mixing Granulator
Low-shear equipment are
- Ribbon mixer
- Plough mixer
High Shear Mixing Granulator
- Rapid Mixing Granulator(RMG)
In high shear or low shear, the process of wetting is performed by the addition of binder solution or solvent.
For Wet Sieving
- Wet Mill
- Wet Granulator
- Manual sieves
A wet mill is attached with RMG and is used to break down the wet mass formed during the kneading process.
For Drying Of Wet Mass
- Fluidized bed dryer (FBD)
- Tray Dryer
For Sieving of dry Grains
- Oscillating Granulator
- Multi Mill /Fitz Mill
- Manual Sieves
Final Mixing
Commonly used mixers for final mixing are as follows,
- Double cone blender
- Sigma mixer
- Bin blenders.
- Cube Mixer
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