1. Problem C1: Spray
Drying
Katipunan, Hazel E.
Lizardo, Syreanne C.
Maniego, Carlo P.
Revalo, Orly M.
5ChE-A

2. • Objectives
 To calculate the heat effects involved in the
operation of a spray dryer
 To determine the efficiency of the spray dryer
used in terms of percentage recovery of the
dried solids.

3. •Equipment / Materials
Spray Dryer with Atomizer 220 V
Air Compressor
Anemometer
Cotton
Detergent

4. •Equipment / Materials
Stirring Rod
Collecting Jar
500-mL beaker
Distilled Water
Timer

5. •Theory
Spray Dryer

6. •Theory
Spray Dryer
• Liquid feed is pumped into a spray-disk
atomizer.
• Droplets are formed inside cylindrical drying
chamber.
• Cooledgas is drawn by an exhaust fan through
a horizontal discharge line set in the side of
chamber.

7. •Theory
Spray Dryer
• Exhaust air passes through cyclone separator.
• Dry solids settles out of the gas into the bottom
of the chamber.

8. •Theory
Advantages of Spray Dryer:
• Very short drying time
• Production of hollow spherical particles
• Desired consistency, bulk density, appearance,
and flow properties of products may obtained
easily compared to other dryers

9. •Theory
• Yieldingfrom a slurry, in a single step, dry
product is ready for package
• May combine the functions of evaporator,
classifier, dryer, crystallizer, or size reduction
unit.

10. •Theory
Disadvantages of Spray Dryer:
• It is bulky and large equipment.
• It is not always easy to operate.
• Bulk
density of dry solid is often difficult to kept
constant.

11. •Theory
Wet Bulb Temperature
• Is the steady-state, non- equilibrium
temperature reached by a small mass of liquid
exposed under adiabatic conditions to a
continuous stream of gas

12. •Theory
Method of measuring the wet bulb
temperature:
•A thermometer or other temperature-
measuring device is covered by a wet wick,
which is saturated with pure liquid and
immersed in a stream of gas having definite
temperature and humidity.

13. •Methodology/Operating Procedure
Prestart-up Guidelines
• Liquid distributor be correctly mounted noting
the wheel be rotating freely
• Air
must be made sure that its not sucked into
the dryer system due to air leakage
• Initial
weight of the collection jar be noted and
fastened securely

14. •Methodology/Operating Procedure
• Compressed air 5 – 6 kg /cm2 (70 – 90 lbs/in2)
supplied
• Air
hose attached to the stud located at the
back of the instrument panel
• Oil
or water separator must be placed I the
compressed air line

15. •Methodology/Operating Procedure
• Prepare slurry containing 30% by mass
detergent
• Weight of dry solids and weight and slurry
before drying

16. •Methodology/Operating Procedure
Startup
• Open the spray dryer unit by turning on the
power
• Operation switch from 0 to M to start the fan
• Switch turned to either I, II or III depending on
inlet air temperature required. Use % timer to
desired air temperature

17. •Methodology/Operating Procedure
• With the heater on and the fan started, the
atomizer be started by completely opening the
air valve
• Distilled
water be passed to the atomizer until
required outlet air temperature obtained
• Switch
to feed slurry after obtaining desired
temperature

18. •Methodology/Operating Procedure
Main Experiment
• Feed the slurry and air temperature at a
constant rate together

19. •Methodology/Operating Procedure
Following Experimental data be gathered
• Inlet air temperature, Ti
• Outlet Air Temperature, Tc
• Operating Pressure of Atomizer
• Absolute Humidity of air at Ti
• Absolute humidity of air at To
• Inlet Temperature of solids, T’
• Air Velocity
• Total Run Time

20. •Methodology/Operating Procedure
• Replacethe Collecting jar after approximately
ten minutes after the contents runs out
• Repeat the process for another feed rate by
varying the opening of feed container

21. •Methodology/Operating Procedure
Shut Down
• Switch
to distilled water noting and regulating
the amount of water fed
• Run the unit for another 5- 10 minutes
• Switch
off the heater, set the % timer to zero,
and operation switch at M

22. •Methodology/Operating Procedure
• Turnoff the water supply and turn off atomizer
3 minutes later
• Introduce cold air through the dryer for 5
minutes
• After
the retained powder have been swept
when air temp is 50 C, turn off operation to
zero

23. •Preparation of Detergent Slurry
x
30 100
x 250

24. THANK YOU!! 