BEST PRACTICES TOWARDS ENERGY EFFECIENCY. UltraTech Cement Limited. (Unit -Kotputli Cement Works)

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1 BEST PRACTICES TOWARDS ENERGY EFFECIENCY UltraTech Cement Limited. (Unit -Kotputli Cement Works)

2 Best Practices towards Energy Efficiency 1. Selected Vertical Mills installed at Raw Mill, Cement Mills & Coal mill instead of Ball Mills, looking to energy efficiency. 2. Selected High recuperation Efficiency Hydraulic Cooler instead of Mechanical Cooler, which is having 72% Efficiency, whereas Mechanical Cooler is having 60-65%. 3. Adopted High Efficient Screw Compressor instead of reciprocating compressor. 4. Adopted CFBC boiler even at small capacity of 2X102TPH because of its efficiency compared to AFBC boiler i.e. (having efficiency of 85% instead of AFBC boiler efficiency 81-82%). 5. All Major Process Fans are with Medium Voltage 6.6KV, 36 Pulse VFD (8 No s). 6. All other Cooler Fans with Low Voltage (690 V) 12 Pulse VFD.

3 Best Practices towards Energy Efficiency 7. Having Intelligent MCC (ABB-MNSIS) with the facility of monitoring of power, even for a smallest motor. 8. Adopted intermediate voltage of 690V for motor rating between KW to reduce rated current and hence I2r losses. 9. Adopted 11KV instead of 6.6KV medium system which reduced distribution losses at MV system. 10. Started 100% Petcoke Firing in Kiln since Nov Installed 100KWp solar power plant to promote green energy. 12. Replacing conventional lightings with LED lightings in phased manner. 13. Installed movement cum occupancy sensor for reduction of lighting running hours. 14. TPP bed ash usage in raw mix. 15. Provided baffle plate (guide plate) inside twin cyclone top duct which is going to down comer duct.

4 Best Practices towards Energy Efficiency 16. To reduce the power consumption and increase the mill stability through Cement mills hydraulic line modification. 17. Hydraulic cooler lane DP optimization with cooler lane CPM. 18. Reduction in LOI at Boiler for increasing Boiler efficiency 19. Reduction in Heat rate by inter connection of both TG condensate Lines 20. Smart Air Flow Controller in Air network for Power saving in Compressors

5 Medium Voltage Drives for all major process fans Objective: 1. Reduction in overall power consumption for cement manufacturing. 2. Constant process parameters for stable operation by close loop speed control. Background: In cement manufacturing Fuel/power cost is very significant (55-60% of total cost). Hence over all cost can be optimized by optimizing flow and speed of process fans like PH fans, BH fans, Cement Mill Fans etc. Fan power is directly proportional to cube time of its speed, hence by optimizing the speed of drives by close loop speed control with process parameters, a significant amount of power can be saved.

6 Medium Voltage Drives for all major process fans Activities: Installation of 8 Nos MV Drives in all process Fans since project stage and also controlling the process parameters in close loop auto control of drive speed. Additionally, KCW is also having 690 V Drives for all cooler fans. Benefits: Less power consumption due to wide speed control Less maintenance as compare to slip ring motor + SPRS. Low Harmonics Almost unity Power Factor (Better efficiency of electrical system).

7 Slip Power Recovery System for Raw Mill Fans Objective: Raw Mill Fan 2 Nos Motors of 3400 KW each, when run in GRR at between 87% to 90% speed and there are losses of power across the GRR (Around 200 to 250 KW), are recovered through SPRS. HT Bus (Grid) ( HT Breaker * HT Isolator ( Motor * M LRS / GRR CONTACTOR SPRS ISOLATOR ( ROTOR TRANSFORMER SPRS CONTACTOR PWM Rotor Converter PWM Source Converter Feedback Transformer Rotor Resistance & Starter Panel*

8 Activities: Slip Power Recovery System for Raw Mill Fans Installation of SPRS to recover power loss in slip Benefits: SPRS will increase in stability of process, as it will operating in close loop and no effect of change in grid frequency and mill stability will improve Total power saving approx KW for each fan at 90% operating speed of fan.

9 Replacement of MH street Lights by LED lights in Township Benefits: Low Power Consumption (90 W instead of 150W) Higher Burning Life (>1,00,000 Hrs in LED and 10,000 Hrs in MH Lamps) Low Maintenance Cost. Low Start / Restrike Time (almost zero in LED and 2-4 minutes in MH Lamps) Lumen Maintenance at the end of Life LED gives 90% output, whereas in MH Lamps it reduces upto 60%

10 CFBC Boiler for Captive Power Plant Objective: 2X102TPH Boilers selected as per load requirement. In this range earlier AFBC Boilers were installed in group units. CFBC Boilers considered in Place of AFBC because of its higher efficiency as a new technology (having efficiency of 85% instead of AFBC boiler efficiency 81-82%)..

11 100 kwp Solar Power Plant (Colony Side) Objective: Promotion of green energy Activities: Solar Power of 100 KWp Mono crystal type cells (437 cells of 230 Wp) technology supplied by M/s Tata BP Solar Ltd. Investment: Benefits: Rs Lacs Approx 1,40,000 KWh/Year to be generated. Subsidy of Rs. 57 lacs from MNRE (Govt of India)

12 Power saving in Compressed air system Objective: Power saving in Compressed air by installing compressed air controller. Investment: Rs Lacs

13 Movement Sensor at Toilets

14 Provided baffle plate inside twin cyclone top duct going to down comer duct Before After P 45 mmwg P 25 mmwg Issues: High Pressure drop across the top bend portion High sp. power consumption of Preheater fans

15 Provided baffle plate inside twin cyclone top duct going to down comer duct Activities: Installation of baffle plates (750*800*12 mm) at twin cyclone top duct which is going to down comer duct. Four plates in a duct at 90 degree angle. Benefits: Fan motor power saved of MWh/annum Annual savings for Rs Lac/annum Payback time calculated as 0.1 months

16 To reduce the power consumption, increase Cement mill stability through hydraulic line modification common HSLM Three separate HSLM Issues: Hydraulic disturbances due to separate hydraulic system for each roller

17 To reduce the power consumption, increase Cement mill stability through hydraulic line modification Activities: Installation of a common HSLM unit for all the 3 master Rollers & soon after this implementation, pressure deviation became nil between all rollers Benefits: Due to Mill stability improvement Mill output increased by 5 TPH Mill Vibration reduced from average 7.8 to 5.5mm/sec Reduce water consumption by average 40KL/day Total potential saving of Rs123.8 Lac/annum Power saving of 3240 Mwh/annum

18 Power saving through reclaimer harrow drive modification Before After Issues: High power drawn by reclaimer harrow drive and Pivot point failure. Load of harrow drive at peak was 70 amp. Material scrapping not proper

19 Power saving through reclaimer harrow drive modification Activities: Replacement of spike rods by 150 mm flat leading to uniform extraction of material. Benefits: Load of harrow drive reduced drastically from 70 amps (Peak) to 45 A (Peak) Annual savings for Rs. 3.7 Lac/annum

20 Optimization of air slide blowers in cement transport Issues: Excess transport air consumption resulting into higher mill sp. Power consumption Bag House To Cement Silos Approach: Interconnection of air blower lines to make common for all blowers delivery 04 nos. of blowers out of 08 stopped under air optimization process Results : Total 30 kw/hr energy saved resulting into Rs Lac / anum savings Zero investment project

21 Power saving through kiln coal conveying line modification Issues: High pressure drop along excess length of kiln coal conveying line High power drawn by conveying blower due to pressure loss to deliver coal at firing point Coriolis feeder 9 mtr. 160 kw blower Approach: Conveying line layout changed to reduce 18 mtr. of pipe length Results : Total 09 kw/hr power saved in blower resulting into Rs. 3.6 Lac/anum Payback period calculated as months

22 Ejector line modification at TPP Opportunity : At the time of Project Ejector motive steam lines were erected as per design with 3 inch dia from PRDS to Ejector for both the Units separately, after commissioning of the plant we were facing problem of Low steam temperature at Ejector inlet i.e. 250 Deg C without de superheating at PRDS while design pressure temperature is 11Ata and 350 Deg C Approach: A brain storming session has organized with TPP all team members and various suggestions have come. In those suggestions team has taken decision for implementation of one suggestion i.e. 6 Inch dia headed from PRDS to near ejectors then 3 inch line to individual ejectors. New 6 inch header erected and connected with existing PRDS and ejectors Results: We have got desired temperature i.e. 350 Deg C and also started de superheating. Ejector efficiency increased and vacuum increases by 0.02 kg/cm2 Saving of 10 Kcal/kwh achieved i.e. Saving of Rs Lacs/annum

23 Auto set point of BFP with Drum Pressure - TPP Opportunity: In Boiler feed Pump we have installed VFD since starting and set point of discharge pressure to VFD is giving manually Approach: Looking to the variable load demand One logic made for auto set point to VFD from Boiler drum pressure. Results: Reduction in Power- 40Kwh/day/pump Saving of Rs Lacs/Annum

24 THE JOURNEY CONTINUES

25 UltraTech