“GreenCoBest Practices Award” · Reuse lime sludge and fly ash to produce“TNPL CEMENT”...
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“GreenCo Best Practices Award”
Transcript of “GreenCoBest Practices Award” · Reuse lime sludge and fly ash to produce“TNPL CEMENT”...
“GreenCo Best Practices Award”
TNPL – Briefly…� World’s largest bagasse based paper plant Promoted by Govt. of
Tamil Nadu in early 80’s
� Presently produces 4,00,000 MT/year of PWP and largest exporter of PWP
� ISO 14001:2004, ISO 9001:2008 , ISO 27001:2013 and FSC FM/COC & CW/COC Certified
� Installed Wind Power Capacity 35.5 MW & Solar Power Capacity 6 KW reducing 45,000 tCO2e GHG Emission
� Reuse lime sludge and fly ash to produce “TNPL CEMENT” first of its kind in pulp and paper industry
� Treated wastewater is used to irrigate 1660 acres by 430 farmers
� 25,000 m3/day biogas generated from bagasse wash water and used in Lime kiln resulting 15 KL F. Oil saving
� 1,12,865 acres Pulp wood plantation since 2004 involving 22,215 farmers
� Four registered CDM project reduces 2.1 Lakh MT CO2 emission
� 200 TPD Precipitated Calcium Carbonate (PCC) Plant and 120 TPD Wet Ground Calcium Carbonate (WGCC) Plant
� Commissioned New Greenfield 600TPD paper board plant TNPL 2
GreenCo Journey
ProgrammeDate of
Completion
Feasibility study Nov 2014
Feasibility study report Nov 2014
Formation of GreenCo Cross Functional Team Members Dec 2014
Training & Handholding Visit 1 Feb 2015
Submission of first draft documents to CII for review Mar 2015
Handholding Visit 2 Apr 2015
Submission of completed documents to CII for review Apr 2015
GreenCo Final Assessment 26th & 27th
May 2015
“Gold Standard” @
GreenCo Summit 2015
25th June 2015
DIPDIPHWHWCBPCBP CRPCRP
3 P/Mc3 P/Mc
Utilities (Energy, WTP and ETPUtilities (Energy, WTP and ETP
Project No 1
LIME SLUDGE AND FLYASH
MANAGEMENT (LSFM) SYSTEM
WASTE TO WEALTH
Methodology Adopted
Major Inorganic
Solid waste
Major Inorganic
Solid waste
Fly AshFly AshLime sludge from 1st
Stage caustisizing
Lime sludge from 1st
Stage caustisizing
CementCement
Lime sludge from
SRP 200 T/day
Fly Ash from
boilers 100 T/day
Capital Outlay Rs 166 Cr
( 136 +30 )
Initial Capacity : 600 Tons/ day
Lime stone
Expansion Capacity :
900 Tons/ day
Lime sludge from
SRP 200 T/day
Fly Ash from
boilers 100 T/day
( 136 +30 )
Capital Outlay Rs 166 Cr
( 136 +30 )
Initial Capacity : 600 Tons/ day
Lime stone
Expansion Capacity :
900 Tons/ day
Trigger major thrust/reason behind
initiating the project
Environmentally and Economically
effective disposal & management of
Solid Waste (Lime Sludge and Fly Ash) and conversion of waste to wealth
Uniqueness of the Project
� Conventional wood based mills follow single stage caustizising
and entire lime sludge is reused.
� Agro based raw material contains relatively high silica content
when compared to wood.
� Silica being one of the major non process element creates various
problems, such as, high viscosity, corrosion, low energy
generation, evaporator & boiler tube plugging and scaling in
chemical recovery cycle.
� Hence, two stage caustizising process is necessary to purge part of
silica entering to chemical recovery cycle to avoid silica build-up in
the system.
� Lime sludge purged from the first stage caustizising is the one of
the major inorganic solid waste and it is unique problem to agro
based mills
White Liquor (Na2S
+ 2NaOH)
2
Lime Kiln
CaO + CO2
Ca CO3
2 2 3
Green Liquor
(Na2S + Na2 CO3
Reused in the
digester
2
100%
Ca(OH)2
3
Caustizising (Na2S +
2NaOH + Ca CO3
H2 O
Uniqueness of the Project
Conventional
wood based
Process
Conventional
wood based
Process
2
Lime Kiln
CaO + CO2
2 2 3Green Liquor (Na2S + Na2 CO3
White Liquor (Na2S
+ 2NaOH)
Ca CO3 With high
silica – solid waste
Ca CO3
2nd Stage
Caustizising (Na2S +
2NaOH + Ca CO3
70% Ca(OH)2
30% Ca(OH)21st Stage
Caustizising (Na2S +
2NaOH + Na2 CO3
+ Ca CO3H2 O
Uniqueness of the Project
Non-Conventional
agro based
Process
Non-Conventional
agro based
Process
Technological Challenges
1. Raw Material blending: Density of Lime Sludge & Stone:
Optimized by various combination of Sludge and Stone ratio as “NO” reference is available
2. High sodium content in the sludge
Introduction of additional washer for sludge washing reduced sodium content in sludge
3. Drying the sludge to 1% moisture by drum washer and then by hot air
Hot air generated from pre heater is used for drying
4. Variation of LOI in the fly ash due to variations in the pith use in Power.
Mixed with Low LOI fly ash from other boilers where pith is not used
Maintenance Challenges
1. Frequent change of bag filter due to damage
No previous experience in bag filter maintenance. Periodical inspection and proper maintenance eliminated the issue
2. Transportation of lime sludge for about 3 km through pipeline
Jamming of pipe line reduced by reduced consistency and line flushing before and after pumping.
Administrative Challenges
�Mini Cement Mill:
Experience personnel are not available for Production
as well as Quality Control
Personnel from Paper Mill is transfer to Cement Mill
�Marketing of Product :
Initially it is sluggish as Cement is manufactured from
Waste.
Product Quality is ensured by Strict Quality Control
department and Market is captured.
Replication potential of the project in
Indian Industry
�All the agro based integrated pulp and paper
industry will have similar issue of silica build-up in
the chemical recovery cycle and generation of
inorganic solid waste from the first stage
� To avoid silica built-up and solid waste issue and to
utilize the fly ash they can adopt this innovative
approach.
Pay Back
Parameter Unit Value
Investment made for 600 TPD Rs in million 1,360
Investment made for expansion to
900 TPD
Rs in million 300
Total investment Rs in million 1,660
Annual savings for 900 TPD Rs in million 400
Payback period month 50
Tangible & Intangible Benefits
Parameter UnitValue
2013-14 2014-15 2015-16
Cement Production MT 1,13,904 1,61,910 1,96,572
Solid waste elimination due to
reuse of Lime sludge
MT 62,631 85,203 78,570
Solid waste elimination due to
reuse of Flyash
MT 20,839 29,621 45,074
Conserved Lime Stone MT 40,418 54,894 50,704
GHG emission reduction due to
lime stone conservation
t CO2 e 17,784 24,193 22,310
Tangible & Intangible Benefits
Parameter UnitValue
2013-14 2014-15 2015-16
GHG emission reduction due to
logistic reduction of lime sludge
t CO2 e 470 639 589
GHG emission reduction due to
logistic reduction of fly ash
t CO2 e 156 222 121
Reduction fuel saving due to
logistics reduction
KL 208 287 236
Total GHG emission reduction
due to LSFM
t CO2 e 18,410 25,054 23,020
Project – 2
REDUCE BLACK LIQUOR CONTENT IN
HARDWOOD FINE REJECTS
TO UTILIZE AS FUEL IN POWER BOILER.
Ha
rdw
oo
d
Dig
est
er
Knots Reused in
the digester
Unbleached pulp
for bleaching
Knotters
ScreenScreen
Recovered fines
send to boiler(fuel)
Recover BL to
recovery boiler
Screw
Press
Twin
Roll
Press
Methodology Adopted
Rejects Stored in
bagasse yard
To effluent
Before ProjectBefore Project
After ProjectAfter Project
Trigger major thrust/reason behind
initiating the project
Reduction & effective management of
disposal solid waste (Hard wood rejects)
with black liquor content under the
concept of waste to energy
Uniqueness of the Project
Designed and implemented internally
to reduce the pollution load
to generate energy from waste &
conserve the resources.
Technological & Maintenance Challenges
Screw press was designed in-house and also there
was no reference data available for this process,
therefore initially many trials were conducted to
optimize the inlet and outlet consistency of the
sludge for trouble free operation
Replication Potential of the Project in
Indian Industry
Can be Replicated in all the wood based integrated pulp and
Paper Industry
Spinoff Project
Enquires are coming from kraft paper mills to use
this material as fibre source.
If it is successful, it will give additional economic
value than using it as fuel in the boiler.
Tangible & Intangible Benefits
Parameter Unit Value
Utilization of fine rejects in the boiler as a fuel
per annum
Mt 1,116
Thermal energy saved per annum GJ 7,704
Saving per annum by utilization Hardwood fine
rejects as fuel
Rs in lakh 19.2
Alkali reused per annum Kg 82,814
Saving per year utilization Hardwood fine rejects
as alkali reused
Rs in lakh 7.7
Black liquor avoided to Effluent m3 9,900
Saving per annum by utilization of Hardwood
fine rejects as black liquor recovery
Rs in lakh 29.6
Emission reduction per annum t CO2 e 1,619
Total saving per annum by utilization Hardwood
fine rejects
Rs in lakh 56.5
Pay Back
Parameter Unit Value
Investment made Rs in lakh 15
Annual savings achieved Rs in lakh 56.5
Payback period month 3
Thanking You
