Basic energy analysis spray dryer

1. ‘Energy Analysis and
Energy Conservation In
Spray Dryers”
Presented By:
Arjun Sarkar
Process Engineer (Food & Dairy projects)
Mob : +91-7042099174
Email : arjunsarkar9@gmail.com

2. Spray Dryer

3. CASE STUDY: FLOW CHART FOR MILK POWDER PLANT

4. Dryer Panel

5. 1. Optimizing the Water
evaporation load.
• Initial and Final TS are to
be optimized.
• Low TS will increase the
heat load in dryer.
• Over-dried product will
also increase the heat
load
• Pre-heating of
concentrate reduces the
sensible heat Load of
dryer.
Dryer : - Heat utilization in drying system
Drying Efficiency Can be Increased By :-
Parameters Units Case-1 Case-2
Inlet Feed kg/hr 3216 3216
Inlet Feed Concentration % 40 45
Moisture in powder % 3 3.5
Powder output kg/hr 1326 1500
Water Evaporation kg/hr 1890 1716
Steam Consumption (Tentative) kg/hr 3591 3261
Steam Savings in Case 2 kg/hr 330
Basic Mass Balance ::: Inlet Feed Rate (kg/hr)*Inlet Feed Concentration(%)=Outlet Feed Rate
(kg/hr)*Outlet Feed Concentration(%)
OPTIMIZATION OF PARAMETERS :: 30 TPD MILK POWDER PLANT

6. 2. Minimizing Heat Losses.
Thermal Efficiency of spray dryer =(Inlet Air
temp- outlet Air Temp)/(Inlet Air temp-
Ambient Temp)
Losses can by reduced by:
• Optimizing the parameters
• Insulation of Dryer body hot air duct can reduce
15% of heat loss.
• Proper Design and Compact General
Arrangement.
• Use of radiator condensate for preheating of air
and concentrate .
• Reducing moisture load in inlet air of dryer.
• Proper handling of powder
• Reducing down time .
Dryer : - Heat utilization in drying system
Parameters Case-1 Case-2
Inletairtemp DegC 190 190
ouletairTemp DegC 85 80
AmbientTemp DegC 20 20
thermal Efficiency 62 65

7. 3. Maximizing Boiler efficiency :
1. Heat recovery in Boiler .
2. Minimum Heat loss in Steam Distribution
3. Use of dryer condensate as feed water in boiler

8. 4. Other Areas for Heat energy Savings :
1. Recovery of Exhaust heat loss.
2. Proper Maintenance.
3. Skilled Labor Management
4. Reducing powder losses from exhaust
(Stack loss)

9. *Note:
• Condensate Outlet Temp. : 60°C
• Ambient Air Temp.: 20°C
Heat Energy savings : Case Study : 30 TPD MILK POWDER PLANT
Parameters Units Case-1 Case-2
Without Heat savings
Mentioned in point 1,2,3,4
With Heat savings
Mentioned in point 1,2,3,4
Inlet Feed kg/hr 3216 3216
Inlet Feed Concentration % 45 45
Moisture in powder % 3.5 3.5
Powder output kg/hr 1500 1500
Water Evaporation kg/hr 1716 1716
Steam Consumption kg/hr 3776 3004
Saving in Case 2 kg/hr 772
Operting time hrs/day 20
Cost of Steam INR/kg 1.5
Running Days per year 300
Net Savings INR/Year 6951059
Savings (approx) 70 Lac
Equivalent amount in USD
(approx) 99301
SAVINGS IN DRYER : HEAT UTILIZATION

10. By Using VFD not only saving of power but also can control powder plant in better manner.
POWER SAVING IN DRYER (30 TPD POWDER PLANT)- 1.5 TPH
Power Loads of Blower
Power Consumption Saving in
terms of Rs.
(Assume
Power cost
Rs. 7/ kwhr)
W/o FVD With VFD
Saving of Power
(Per hour)
Per Annum
Saving (24 hrs a
day X 300 days
an annum)- kwhr
 Homogenizer cum high
pressure pump
 Main Supply to Spray
Dryer
 Exhaust Blower
 Supply IFBD
 Supply FBD
 Supply FBC
 Exhaust FBD
283 198 85 612000
42,84,000
USD 60,000
Power savings : Case Study : 30 TPD MILK POWDER PLANT

11. leading manufacturers and exporters of Spray Dryers

12. Opex is like paying money of petrol for your vehicle,
Unavoidable. But It is feasible and sensible to keep it
minimum as far as possible to keep the budget low.