Pharmaceutical engineering B pharmacy 3rd sem Freeze drayer ( Construction working principle, merits , and demerits .

1. Pharmaceutical Engineering
Topic - Freze Dryer
( Principle, Construction, Working, Merrits,
Demerrits )
Dr Naikwadi Collage Of Pharmacy
Presented By - Purushottam Mali
2nd Year B Pharmacy
Roll No 58

2. ACKNOWLEDGEMENT
I would like to express my special thanks of gratitude to our
"Pharmaceutical Engineering" professor respected
“ Mr. Aadarsh Wagh "who gave us the golden opportunity to do this
wonderful presentation on topic."Principle, Construction, Working,
Merrits,Demerrits Of Freeze Dryer."

3. Contents
• Introduction
• Principle
• Construction
• Diagram
• Working
1. Preperation And Pretreatment.
2. Pre Freezing For solidifying water.
3. Primary Drying
4. Secondary Drying & 5. Packing
• Uses
• Merrits
• De- Merrits

4. Introduction
• Drying is an important technique used in the
pharmaceutical industry.
• Drying can prevent deterioration of the product
and it also improves the solubility.
• It is usually applied to the removal of small
amounts of water or other liquid from solids by
the application of heat.
• Water Vapour is removed at temperatures
below the boiling point of water.

5. Principle
• water is removed from the frozen state
sublimation.
• The drying is achieved by subjecting the material
to temperature and pressures below the triple
point.
• Under these condition any heat transferred is
used as latent heat and ice sublimes directly
into vapour state.

6. Construction
The Construction of Freze Dryer Is Consist Of
1. Vacuum chamber
2. Heat supply in the form of radiation source, heating coils
3. Vapour condensing or adsorption system.
4. Vacuum pump or steam ejector or both.
👉 The distance between subliming surface and condenser must be
less than the mean path of molecules. That increases the rate of
drying.
👉The temperature of the condenser must be lower that the
evaporated surface of frozen substance.

7. Freze Dryer

8. Working
It consists of the following steps :
1. Preparation and pretreatment
2. Pre freezing for solidifying water
3. Primary drying ( sublimation of ice under vaccum)
4. Secondary drying ( removal of residual moisture
under high vacuum)
5. Packing

9. 1) Preparation And Pretreatment
• The volume of solution introduced into the flask
is limited by its capacity
• Satisfactory freeze drying is not possible
because of the certain limit of dept so
pretreatment is essential.
• The solution is pre concentrated under normal
vacuum tray drying. This Reduces the actual
drying by 8 to 10 times. The final product
becomes more porous.

10. 2) Pre freezing To solidify water
• Vials, ampoules or bottles in which the
aqueous solution is packed are frozen
in cold shelves about – 50ْ C.
• During this stage , cabinet is
maintained at low temperature
atmospheric pressure.
• The normal cooling rate is about 1 to 3
kelvin / min.

11. 3) Primary Drying
• The material to be dried is spread as much large surface as possible
for sublimation.
• Temperature and pressure should be below the triple point of water
i.e., 0.0098ºC and 0.533 kilopascals for sublimation .
• Vacuum is applied to the tune of about 3mm Hg on the frozen
sample.
• The temperature is linearly increased to about 30ºC in a span of 2 hr.
• Heat heat is transfer as latent heat and ice sublimes directly into
vapour state.
• As soon as vapour molecules are formed these are removed.

12. 4) Secondary Dryig & 5) Packing
( removal of residual moisture under high
vacuum):
• Traces of moisture is removed but
temperature of solid is raised to as 50 to
60ºC.
• But vacuum is lowered below that is used in
primary drying.

13. Uses
It is most commonly used in the production of
dosage forms, such as injections, solutions and
suspensions.
1. It is used for drying of a number of products.
Blood plasma and its fractionated products.
2. Bacterial and viral cultures.
3. Human tissue ( arteries and corneal tissue).
4. 4) Antibiotics and plant extracts.
5. 5) Steroids, vitamins and enzymes.

14. Merrits
The entire operation is carried out well below the
freezing point.
1) Thermolabile materials can be dried.
2) Denaturation does not occur.
3) Loss of volatile material is less.
4) Sterility can be maintained.
5) Material can be dried in its final container
such as single dose and multiple dose vials.

15. De- Merrits
Disadvantages:
1) Equipment and running costs are high.
2) 2) It is difficult for solutions containing
non aqueous solvents.
3) The period of drying is high.
Time cannot be shortened.

16. Reference
1)Pharmaceutical Engineering by Dr. Md. Rageeb
Md. Usman.
Nirali Publication 2021 Edition.
2) Pharmaceutical Engineering By Shalinj Sharma
Pee Vee Publication 1 janury 2018’s Edition.
3) www.pharmastuff.Blogspot.Com

17. Thank You 💫