"Best Practices in Energy Efficiency in Cement Sector" under KEP initiative

Transcription

1 "Best Practices in Energy Efficiency in Cement Sector" under KEP initiative Presentation by, JSW Cement Ltd, Nandyal Works My Home Industries 7 th & 8 th July

2 Management Systems 2

3 JSW CEMENT, NANDYAL WORKS 3

4 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

5 Two Major Encon Projects of FY Pyro Floor Cooler Optimization Operation of Cement Grinding Roller Press in Finish Mode 5

6 PYROFLOOR COOLER OPTIMIZATION 6

7 Objectives of the project To Avoid snowman formation Increase cooler efficiency Reduce Sp. Heat Cons. 7

8 Design Specification Model Pyro floor cooler type PFC 757A with roll crusher Capacity 6000 TPD clinker production Clinker Temp 65 degc + ambient 8

9 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

10 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

11 Cooler Horse Shoe Modification 11

12 Cooler fans upgradation PARAMETER Unit FAN-1 FAN-2 FAN-3 FAN-4 Flow m3/s 22.5 to to to to 20.0 Motor Kw kw 400 to to

13 Installation of shock blowers 13

14 Inter compartment leakage arrest 14

15 Key Performance Indicators PROCESS PARAMETER UOM Before After Clinker Production tpd SAT DegC TAD DegC Cooler Vent DegC Clinker Temp DegC Recuperation Efficiency % Sp. Heat consumption Kcal/kg clinker

16 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

17 Operation of Cement Mill RP in Finish Mode 17

18 Objectives of the project Reduce Sp. Power Eliminate Water spray Setting Benchmark for Future Projects 18

19 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

20 Design Specification Capacity m2/kg Blaine Technology KHD Roller Press with Ball Mill Comflex Technology Sp. Power Kwh/ton of 320 m2/kg Blaine 20

21 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

22 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

23 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

24 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

25 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

26 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

27 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 Velocity m/sec Flow m3/hr Nm3/hr AFTER unit SKS fan V-separator inlet RP1 RP2 mm Wg m/sec m3/hr Nm3/hr

28 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

29 Key Performance Indicators PROCESS PARAMETER UOM SEMI-FINISHED FINISHED-MODE Feed tph Fineness m2/kg Roller press power KW Hydraulic pressure bar Separator drive load KW Process fan power KW Ball mill drive power KW Ball mill water spray Litre/t Specific power Kwh/t

30 Quality Parameters Comparison Parameters Semi-finish Finish Compressive strength Blaine Water demand Setting time initial/final 215/ /270 1 day days days days day 3 days 7 days 28 days RP+BM RP 30

31 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

32 32