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TRANSCRIPT
"Best Practices in Energy Efficiency in Cement Sector"
under KEP initiative
Presentation by,
JSW Cement Ltd, Nandyal Works
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CEMENT
@ My Home Industries
7th & 8th July 2016
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Management Systems
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JSW CEMENT, NANDYAL WORKS
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Product Portfolio and Production Capacity
• JSW entered the cement market in 2009 with a vision to ensure a sustainable future for the country by producing eco-friendly cement, using industrial by-products such as slag
• JSW Cement produces three varieties of products: Portland Slag Cement (PSC), Ordinary Portland Cement (OPC), and Ground Granulated Blast Furnace Slag (GGBFS).
• Not only does JSW Cement manufacture one of the most eco-friendly cements in India, but it also engineers its products for superior strength and durability.
• The plant has a capacity is to produce Clinker ~ 2.50 million ton per annum (mtpa) and Cement ~ 4.80 mtpa
• It’s a state-of-the-art technology cement production unit at Bilakalaguduru village near Kurnool District, Andhra Pradesh.
INTRODUCTION
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Pyro Floor Cooler
Optimization
Operation of Cement
Grinding Roller Press in Finish
Mode
Two Major Encon Projects of FY 2015-16
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PYROFLOOR COOLER OPTIMIZATION
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To Avoid snowman formation
Increase cooler
efficiency
Reduce Sp. Heat Cons.
Objectives of the project
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Model
• Pyro floor cooler type PFC 757A with roll crusher
Capacity• 6000 TPD clinker production
Clinker Temp
• 65 degC + ambient
Design Specification
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Snowman• Frequent snowman formation
Sp. Heat cons.
• High specific heat consumption due to poor cooler recuperation efficiency
Clinker Temp
• High clinker temperature which impacts on cement mill operation
Driving Forces for the Idea
Cooler static grate horse shoe modification
Horse shoe base area reduced and static grate area increased by 5%
First four cooler fans upgraded
Calibration of cooler bed height sonar
Cooler inter compartment leakage arrested
Installation of new shock blowers
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Modifications done to increase cooler efficiency
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Cooler Horse Shoe Modification
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Cooler fans upgradation
PARAMETER Unit FAN-1 FAN-2 FAN-3 FAN-4
Flow m3/s 22.5 to 29.7 18.33 to 23.33 16.25 to 18.9 16.83 to 20.0
Motor Kw kW 400 to 520 315 to 400 250 250
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Installation of shock blowers
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Inter compartment leakage arrest
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PROCESS PARAMETER UOM Before After
Clinker Production tpd 6600 6600
SAT DegC 1000-1050 1050-1100
TAD DegC 850-875 925-950
Cooler Vent DegC 350-375 300-330
Clinker Temp DegC 180 120
Recuperation Efficiency % 57 66
Sp. Heat consumptionKcal/kg
clinker740 709
Key Performance Indicators
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Energy
• Sp. heat cons. reduced from 740 to 709 kcal/kgclinker
• Cooler recuperation efficiency increased from 57 % to 66%
Snowman& Clinker
temp
• No snow man formation after modification
• Clinker temperature reduced from 180 to 120 degC
Cost
• Total annual savings of 3.60 crores/annum
• Stable kiln operation and improved clinker quality
Report on Savings
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Operation of Cement Mill RP in Finish Mode
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Reduce Sp.
Power
Eliminate Water spray
Setting Benchmark for Future Projects
Objectives of the project
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1 Pre-Grinding by RP
2 Semi-Finish-Grinding by RP
3 Semi-Finish-Grinding by RP with VS
4 Semi-Finish Grinding by RP with VSK
5 Cement grinding by RP & BM with VSK
6 Slag Grinding by RP & VSK
7 Grinding by RP & VSK “W ”
8Grinding by RP –
COMFLEX SYSTEM
Evolution of Roller Press
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Capacity• 350 tph @ 320 m2/kg Blaine
Technology
• KHD Roller Press with Ball Mill
• Comflex Technology
Sp. Power
• 26.00 Kwh/ton of OPC @ 320 m2/kg Blaine
Design Specification
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Test run in finish grinding mode without Ball mill
Identification of main constraints
Brain storming and task force selection
Modifications
Process optimisation
Implementation Strategy
Challenges Faced on Finish Mode
Roller Press Skewing Problem
High recirculation of fine material
Uneven feed distribution to two roller presses
Material flushing from RP prebin
Heavy roller press vibration
Frequent shear pin cut problem
Difficult in handling separator reject material
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Modifications done to overcome challenges
MAJOR CONSTRAINTS SOLUTIONS
High vibration levels in roller press due to high fine material re-circulation and material segregation in pre-bin
Homogenised feed to roller press by fines and coarse mixing
Material flushing from RP pre-bin and unstable operation
Maintain consistent pre-bin level by roller press feed chute modification
Material flushing from V-separator discharge and belts overloaded leads to stoppage
V-separator discharge chute modification
Not able to achieve the required fineness of 350 kg/cm2
Improve the V-separator and dynamic separator efficiency
Not able to achieve the required production Process optimisation
Gap reduced from
130mm to 70 mm
Roller press feed chute height and width reduced
Roller Press Feed Chute Modification
TARGET: To achieve consistent material flow to roller press by maintaining stable pre-bin level
Due to more gap between feed chute discharge to roller surface, material column sliding and pre-bin flushing which leads to heavy vibrations and unstable operation
Feed chute gap reduced from 130 mm to 70 mm,chute width reduced from 500 mm to 400 mm
Material flushing reduced and consistent material flow increased roller press grinding efficiency
400 mm
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Before After
Material segregating inside pre-bin and passing through roller press resulting high pressure and gap differences leads to poor grinding efficiency.
Mixing box installed by reducing the chute width to mix coarse and fines to give homogenous feed to roller press and improve the grinding efficiency.
RP Prebin Feed Chute Modification
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Installation of two pipe chutes with dosing gates from dynamic separator reject bin to V-separator discharge belt which results:
Reduced RP vibrations due to well homogenization of separator rejects with fresh feed
SKS rejects feeding to V-sep Discharge
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Parameter unit SKS fanV-separator inlet
RP1 RP2
Static pressure mm Wg - 450 -10 -30
Velocity m/sec 17.8 14.38 19.84
Flowm3/hr 499243 150971 248423
Nm3/hr 324005 97979 161225
unit SKS fanV-separator inlet
RP1 RP2
mm Wg - 465 -12 -13
m/sec 17.35 17.86 17.68
m3/hr 486872 192801 196696
Nm3/hr 312864 123894 126397
BEFORE AFTER
From the gas flow measurements difference was found between RP1 & RP2 V- separator efficiency due to blockage of V-separator feed inlet chute.
After blockage removal equal gas flow distribution was achieved and process efficiency increased.
V-Separator Gas Flow Optimization
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Mixing box installation in intermediate feed bin to achieve homogenised fresh feed
Roller press de-dusting system modification for better venting to reduce vibrations
SKS reject bin inlet chute modification and de-dusting system provided for better distribution
All the belt conveyor and bucket elevator discharge chutes were re-designed by reducing the opening to avoid material flushing and overloading
Installation of cake breaker beam at roller press discharge to improve separation efficiency
Further Improvements for Stable Operation
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PROCESS PARAMETER UOM SEMI-FINISHED FINISHED-MODE
Feed tph 293 240
Fineness m2/kg 330 350
Roller press power KW 5510 5520
Hydraulic pressure bar 140 142
Separator drive load KW 175 140
Process fan power KW 1100 910
Ball mill drive power KW 2000 0
Ball mill water spray Litre/t 5.5 0
Specific power Kwh/t 29.48 27.38
Key Performance Indicators
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Parameters Semi-finish Finish
Blaine 330 330
Water demand 28.6 28.4
Setting time initial/final
215/290 200/270
1 day 23.7 25.2
3 days 36.6 40.9
7 days 47.2 52.1
28 days 62.1 66.40
10
20
30
40
50
60
70
1 day 3 days 7 days 28 days
RP+BM
RP
Compressive strength
Quality Parameters Comparison
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Energy
• Sp. Power Savings of 2.10 kwh/ton of OPC with superior quality of product
Water• Water savings of 5.50 liters/ton of OPC
Cost
• Total annual savings of 1.23 crores/annum
• Reduction in capital cost for future projects
Report on Savings
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