different process

1. Drying
By – Kiran C.Rodge

2. • Definition- The removal of small amounts of water or
other liquid from material by the application of heat.
• Application –
 Preparation of bulk drug
 Preservation of drug product
 Improved characteristic
 Improved handling

3. Theory of Drying
• Bound Water-the minimum water held by the material
that exerts an equilibrium V.pressure less than the pure
water at the same Temp.
• Unbound water-the amount of water held by the
material that exerts an equilibrium V.pressure equal to
that of the water at the same Temp.

4. • Equilibrium Relationship –
• EMC - it is the amount of water present in the solid
which exert a V.pressure equal to the V.pressure of the
atmosphere surrounding it.
• Desorption
• Sorption
• FMC - FMC = Total water content – EMC

5. • Equilibrium Relationship
% LOD = Mass of water in sample
* 100
Total mass of wet sample
% MC = Mass of water in sample
* 100
Total mass of dry sample
Drying rate = Weight of water in sample
Time * Weight of the dry solid

6. Classification of Dryer
Static bed Dryer
 Tray dryer
 Freeze Dryer
Moving Bed Dryer
Drum Dryer
Fluidised Bed Dryer
Fluidised Bed Dryer
Pneumatic Dryer
Spray Dryer

7. Drying Equipments
• Tray Dryer

8. Drum Dryer

9. Spray Dryer

10. Fluidized bed Dryer

11. Vacuum Dryer

12. Freeze Dryer