This document summarizes research on integrating a heat recuperation unit (HRU) into the jaggery making process to improve energy efficiency. The HRU uses a packed bed to preheat incoming air with waste heat from furnace exhaust. Researchers built a proof-of-concept HRU unit and tested it at IIT Bombay. Dynamic simulations of the HRU matched reasonably well with experimental temperature data. The HRU demonstrated potential to recover waste heat from flue gases and improve the thermal efficiency of jaggery production. Overall, the study evaluated integrating an HRU to reduce energy usage in jaggery making through waste heat recovery.

1. Paper ID: 374
Integration of Heat Recuperation Unit (HRU)
in Jaggery Making Process
Sagar Jangam*, N G Shah*, Kannan Iyer** and Sanjay Mahajani***
* CTARA, IIT-Bombay
** Mechanical Engineering Department
*** Chemical Engineering Department
Indian Institute of Technology Bombay, Powai, Mumbai 400 076
Acknowledgement:
Funding: RGSTC, Maharashtra Government.
Technical help : Kiran Shiralkar, Sravankumar K., and Gagan Garg,
Research Students @ IITB

2. Jagerry making process and equipments
Cane crusher
Boiling pan (MS)
3 m dia & 0.5 m ht
750 lit
Settling tank
Cooling pan
furnace
Moulds and storage

3. Jaggery process
Energy Analysis and improvements
Chimney
Heat
Losses
Energy analysis
Waste heat recovery

4. 4

5. Case for Thermal Efficiency Improvement
in Jaggery Making
(Material and Energy balnace)
• Assuming Heat transfer efficiency of 50 % .
• Jaggery unit holders are concerned about sufficiency of
bagasse.
• Measurements indicate :
Baggase Available:
1.9 kg/ kg
Currently used : 1.5-1.9 kg/kg
5

6. Chimney Temperatures Monitored in
Field-Units
T7
T4
T1
T6
Temperature variation in furnace, chimney and juice during a batch (T1 Juice Temp)
Batch Time - 2 to 3 hrs.
Juice Temp – 100oC - 118oC towards the end. Furnace Temp- 500-800oC.
Exhaust Temp - High 350-500oC
Chimney Effluents - O2 :- 5-6% CO2 :– 14-15%
Upto 50% excess air being sucked into the furnace
6

7. Schematic of Heat Regeneration Unit

8. Lab Scale HRU Unit – POC Model Tested at IITB Lab

9. Ta, cpa
Air out
Air in
x
dx
Ts, Cps
Schematic representation of the domain of
the HRU

10. Governing Equations for computing temperatures of
the packing and the gas:

11. 700
Temp of gas
600
Temp of solid
Temp of air
Temperature (°C)
500
Temp of solid in return flow
Temp of gas 2nd turn
400
Temp of solid 2nd turn
300
200
100
0
0
0.1
0.2
0.3
0.4
0.5
0.6
Length (m)
Temperature profiles of gas, air and solid along the bed
length in two consecutive cycles

12. 600
250
Temperature (°C)
Temperature (°C)
500
400
300
200
100
Hot test 1
0
200
150
100
Hot Test 1
Hot Test 2
0
25
50
75
100
50
Hot Test 2
0
125
150
0
25
50
Time (min)
75
100
125
150
Time (min)
a : Furnace exit
b: Bed Temperature (R1)
Temperature (°C)
200
Temperature (°C)
200
160
120
80
HT1
160
HT2
120
80
40
Hot Test 1
40
0
Hot Test 2
0
0
0
25
50
75
100
125
150
25
50
75
100
125
Time (min)
Time (min)
C: Bed temperature (R2)
d: Pre-heated air
150

13. 140
Temperature in °C
120
100
80
Ts prog.
60
Ts Exp.
40
20
0
0
2
4
6
8
10
12
Time (min)
Comparison of experimental and simulated
temperatures of the flue gas

14. CONCLUSIONS
 The dynamic simulations of HRU, incorporating
randomly packed bed of marble pebbles, enabled
building a POC Unit built and tested in IITB Labs
HRU unit designed in the present work is capable of
recovering waste heat from the flue gas.
The trends obtained by simulation and experiments
match reasonably well.

16. Process Improvements and
Technology Dissemination
in
Jaggery Making
Centre for Technology Alternatives
for Rural Areas
IIT-Bombay
16