MechanismofSIZEREDUCTION

1. TOPIC: Mechanism of SIZE Reduction
PHARMACEUTICAL ENGINEERING
Prepared by kashish Wilson
Assistant Professor,
MM College of Pharmacy,
MM(DU),Mullana Ambala

2. Precipitation process :
• Substances is dissolved in an appropriate solvent. Subsequently, it is finely precipitated by
the addition of another solvent.
• Which is miscible with the first, but in the later substance is insoluble.
• This method is suitable for the production of raw materials and bulk drugs.
Mechanical process:
 The substances is subject to mechanical forces using grinding equipment.
E.g.: ball mill, roller mill.
 Dry grinding or milling is used in the production of tablets, capsules.
 Wet grinding is used in the preparation of suspensions, emulsions and
ointments.

3. Modes of size reduction:
Cutting: The material is cut by means of a sharp blades
Eg : cutter mill
Compression:
 In this mode material is crushed between roller by the application of
pressure Eg : roller mill
Impact:
 This involve the operation of hammer/bars at high speeds.
 When a lump of material strikes the rotating hammers, the material splits
apart. Eg : fluid energy mill
Attrition: breaking down by the rubbing action between two surfaces.
Eg : fluid energy mill, ball mill

4. Thank you