"Best Practices in Energy Efficiency in Cement Sector" under KEP initiative Presentation by, JSW Cement Ltd, Nandyal Works CEMENT @ My Home Industries 7 th & 8 th July 2016 1
Management Systems 2
JSW CEMENT, NANDYAL WORKS 3
INTRODUCTION 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). Product Portfolio and Production Capacity 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. 4
Two Major Encon Projects of FY 2015-16 Pyro Floor Cooler Optimization Operation of Cement Grinding Roller Press in Finish Mode 5
PYROFLOOR COOLER OPTIMIZATION 6
Objectives of the project To Avoid snowman formation Increase cooler efficiency Reduce Sp. Heat Cons. 7
Design Specification Model Pyro floor cooler type PFC 757A with roll crusher Capacity 6000 TPD clinker production Clinker Temp 65 degc + ambient 8
Driving Forces for the Idea 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 9
Modifications done to increase cooler efficiency 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 10
Cooler Horse Shoe Modification 11
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 12
Installation of shock blowers 13
Inter compartment leakage arrest 14
Key Performance Indicators 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 consumption Kcal/kg clinker 740 709 15
Report on Savings Energy Sp. heat cons. reduced from 740 to 709 kcal/kgclinker Cooler recuperation efficiency increased from 57 % to 66% Snowman & Clinker temp Cost No snow man formation after modification Clinker temperature reduced from 180 to 120 degc Total annual savings of 3.60 crores/annum Stable kiln operation and improved clinker quality 16
Operation of Cement Mill RP in Finish Mode 17
Objectives of the project Reduce Sp. Power Eliminate Water spray Setting Benchmark for Future Projects 18
Evolution of Roller Press 8 Grinding by RP COMFLEX SYSTEM 7 Grinding by RP & VSK W 6 Slag Grinding by RP & VSK Cement grinding by RP & BM with VSK 5 4 Semi-Finish Grinding by RP with VSK Semi-Finish-Grinding by RP with VS 3 Semi-Finish-Grinding by RP 2 Pre-Grinding by RP 1 19
Design Specification 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 20
Implementation Strategy Test run in finish grinding mode without Ball mill Identification of main constraints Brain storming and task force selection Modifications Process optimisation 21
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 22
Modifications done to overcome challenges MAJOR CONSTRAINTS High vibration levels in roller press due to high fine material re-circulation and material segregation in pre-bin SOLUTIONS 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 23
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 Gap reduced from 130mm to 70 mm Roller press feed chute height and width reduced 400 mm
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 Before After 25
SKS rejects feeding to V-sep Discharge 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 26
V-Separator Gas Flow Optimization 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. BEFORE Parameter unit SKS fan V-separator inlet RP1 RP2 Static pressure mm Wg - 450-10 -30 Velocity m/sec 17.8 14.38 19.84 Flow m3/hr 499243 150971 248423 Nm3/hr 324005 97979 161225 AFTER unit SKS fan V-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 27
Further Improvements for Stable Operation 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 28
Key Performance Indicators 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 29
Quality Parameters Comparison Parameters Semi-finish Finish Compressive strength Blaine 330 330 70 Water demand 28.6 28.4 60 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 66.4 50 40 30 20 10 0 1 day 3 days 7 days 28 days RP+BM RP 30
Report on Savings 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 31
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