1. COGENERATION ENHANCEMENT USING LOW PRESSURE VAPOUR FOR CRYSTALLISATION
By: VIVEK VERMA

2. MISSION STATEMENT Dedicated for Sustainable Environment Development
to Unlock Perpetual Food and Energy Resources.

3. HIGHLIGHTS Dhanalakshmi Srinivasan Sugars Pvt. Ltd. (DSSPL), Tamilnadu
3500 TCD Plant
Current Steam Consumption 31-32% on cane
Power export kWh/Ton of cane
Sugar Colour < 35 IU
Modern boiling house with FFEs, DCH, SCP® for all Massecuite
2 roller 4-mill tandem plant
40% savings on power consumption by AC-VFD Motors
Fully automated Sugar and Co-Generation units with DCS controls

4. BOILING HOUSE CONFIGURATION
Quintuple Evaporator Station with seven identical Tubular FFEs (1500 m2)
Total HS = 10,500 m2 [9000 m2 - operation and 1500 m2 – in standby]
Condensate Flash Vessel System
DCH for Raw, Defecated and Clear Juice & Syrup heating
Single Floating Evaporator for cleaning all effects
Working temp. range: 125°C to 75°C
All massecuite boiling through SCP® using 4th effect vapour

5. OPERATING SCHEME AT DSSPL

6. OPERATING PARAMETERS Sr. No. Effects Operating Pressure (bar A)
Operating Temp. (0C)
Operating ∆T 1
1st Effect
1.8–1.9
6-80C 2
2nd Effect
8-90C 3
3rd Effect
98-102
7-100C 4
4th Effect
93-96
5-70C 5
5th Effect
75-78
12-150C

7. BLEEDING ARRANGEMENT Sr. No. Description Configuration
Operating Temperature 1
MJ 1st Heating
Pan Vapour C 2
MJ 2nd Heating
5th Effect C 3
DJ 1st Heating
4th Effect C 4
DJ 2nd Heating
3rd Effect C 5
DJ 3rd Heating
2nd Effect C 6
CJ 1st Heating 7
All Pans (A, B, C & R) C

8. CRYSTALLISATION & STEAM CONSUMPTION
Evaporator bleeding for Pan Boiling directly effects the steam demand.
Present design of pans prevent it to be operated with low pressure vapour.
SCP® is the solution for reducing steam demand.
Shifting of vapour for pan boiling to later effects indirectly helps in rising the liquor brix close to saturation alongwith direct steam saving.
Crystallisation using later effect drives evaporator sizes identical ; only the single evaporator is required as standby.

9. EVAPORATION LOAD DISTRIBUTION
Conventional Plant
DSSPL, Tamilnadu

10. EFFECT OF CRYSTALLISATION ON STEAM
Steam Consumption

11. CONVENTIONAL PAN 40% 35% 10% 5% Effect – I 115°C Steam 45% on
Effect – II
105°C
Effect – III
90°C
Effect – IV
75°C
Effect –V
55°C
Steam 45% on
Cane - 120°C
40%
35%
10% 5%
Condensate

12. VERTICAL CONTINUOUS VACUUM PAN(SCP®)
Effect – I
115°C
Effect – II
105°C
Effect – III
95°C
Effect – IV
80°C
Effect – V
55°C
Steam 35% on
Cane - 120°C
32%
28%
20%
18% 2%
Vapours
15%
Condensate

13. CRYSTALLISATION SECTION
3 Nos. of Vertical Continuous Vacuum Pan (SCP®) for all Massecuite boiling.
Capacity of SCP®A – 50 TPH, B – 20 TPH, C – 15 TPH, R1 – 25 TPH and R2 – 20 TPH.
Molasses Conditioner for AH, BH, CL
R1 molasses of direct contact heating type.
2 Nos. of Seed Crystallizer of 20T for A and B Seeds.
2 Nos. of Grain Crystallizer of 30T for B and C Grain.
5 Nos. of supply tanks of 2 for syrup & melt and 3 for molasses storage.

14. COLOUR VALUE OF VARIOUS STREAMS
S. No.
Descriptions
Colour Value(IU) 1.
Primary juice
26500 2.
Mixed Juice
28540 3.
Clear juice
15458 4.
Syrup
15750 5.
“A” M/c
9200 6.
“B” M/c
15040 7.
“C” M/c
20453 8.
R1 M/c
950 9.
R2 M/c
1150
10.
A Heavy
15304
11.
B Heavy
22680
12.
C Light
24540
S. No.
Descriptions
Colour Value (IU)
13.
Final Molasses
28400
14.
R1 Mol.
1023
15.
R2 Mol.
1437
16.
Raw Melt
570
17.
Clear Melt
342
18.
B & C Melt
4550
19.
C Seed
2400
20.
C fore Sugar
3715
21.
C after Sugar
3180
22.
R1 Sugar 24
23.
R2 Sugar 41
24.
Blended 34

15. COGEN EFFICIENCY COMPARISION
DSSPL, Tamilnadu
Conventional Plant

16. COGENERATION Particulars Unit SEASON WISE 2014-15 2013-14 2012-13
Plant Crushing Rate MT
3200
3000
2000
1600
2200
1900
Power Consumption
kWh/T
29.40
30.84
30.79
32.13
32.63
38.17
Sugar Colour IU
33.93
MONTH WISE
Jan-2016
Feb-16
Mar-16
Apr-16
Power Generation
kWh/T
135.96
128.11
135.85
135.35
Power Consumption
32.5
29.81
31.86
30.14
Power Export
103.46
99.3
103.99
105.21

17. PLANT VIEWS

18. RESULTS Sr. No. Descriptions/Parameters Value 1. Crushing Capacity
3500 TCD 2.
Cane Crushed (MT)
5.0 Lakh 3.
Bagasse % Cane
27.5 4.
Fibre % Cane
13.10 5.
Steam Consumtion of the Plant
31-32% on cane 6.
Total Heating Surface Area of FFEs
10,500 m2 7.
A Masseciute (%) cane 29 8.
B Massecuite (%) cane 11 9.
C Massecuite (%) cane
8.5 10
Refined Sugar (R1) (%) cane 28
11.
Refined Sugar (R2) (%) cane 21
12.
Sugar Colour
< 35 IU
13.
Power Export
kWh/Tons

19. CONCLUSION Enhanced Power Generation (100 - 105 kWh/T)
by crystallization with 4th effect Falling Film Evaporator
using innovative approach and efficient technologies.

20. THANK YOU