PRISM CEMENT LTD. CEMENT WORKS MANKAHARI, SATNA

Transcription

1 P R I S M C E M E N T PRISM LTD. WORKS MANKAHARI, SATNA ENERGY EFFICIENCY : A GIZMO MK JHA BN SINGH NP SINGHAI

2 U-II : 3.5 MTPA Cement Commissioned : Jan 2011 U-I : 3 MTPA Cement Commissioned : 1997

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4 Energy Conservation call of Time, World and Forthcoming Generations For Sustainability of Quality Life. Presentation recites success story at Prism Cement Ltd, wherein turn around at energy front happened due to able guidance and zeal to excel, without much of investment.

5 Plant Capacity SECTION UNIT-I UNIT-II Clinkerisation 6000 TPD (Guaranteed) 7200 TPD (Guaranteed) 7200 TPD (Potential) 8000 TPD (Potential) Cement Grinding 3.0 MTPA (PPC) 3.6 MTPA (PPC) Core Equipment Capacity SECTION Lime stone Crusher Raw Mills Kiln Coal mill Cement Mills UNIT-I 1200 TPH 275 TPH x 2 nos TPD / 7200 TPD 65 TPH 180 TPH x 2 nos. UNIT-II 750 TPH x 2 nos 300 TPH x 2 nos 7200 TPD / 8000 TPD 74 TPH 275 TPH x 2 nos Packers 120 TPH x 6 nos. 240 TPH x 5 nos

6 PURSUIT TO ENERGY EFFICIENCY PAT is an activity that encourages conservation through rewards. We created energy forum to comply with PAT requirements. Baseline SEC as 783 kcal/kg of equivalent product. Target SEC as 749 kcal/kg of equivalent product. Arrived at way forward suiting plant condition, on following Base: preventing losses adopting innovative methods of operation, re-visiting the equipment design & specifications with respect to operational needs modifying the equipment to fit in operation point. Process optimisation, Intensive monitoring to avoid idling, effective use of industrial waste materials, alternate sources of cheaper electricity, grass-root level involvement through awareness campaigns

7 We planned a systematic energy audit arrived at a job list based approach, as described below: Sl Job Description Expected Saving kw/hr. Achieved Saving kw/hr. JOB LIST FOR UNIT-I 1 Identify the list of under loaded motors ( < 50% loading) Identify the motor having poor power factor Study of process fans efficiency and plan for retrofit Study for optimisation of bag filters purging sequence and time Compressor monitoring with CCR Proposal of bag filter fan VFD in Unit-I VFD requirement in P&V system to control the fan speed PID loops optimisation & new PID Remarks U-I Cooler ESP Fan being changed, rest planned in phased manner during this FY

8 Sl Job Description Expected Saving kw/hr. Achieved Saving kw/hr. 9 Cooling tower fan optimisation with temp control Idle running of Unit-1 (Crusher -U1) 250 By 2 Shift operation Scope of power less exhaust fan, LED light & 11 control switch scheme in plant and building (U-1) Power saving of changing booster pump from kw to 18 kw and others saving scope in DG 5 6 Solar lighting system for guest house, ADM. 13 building, CCR and school building Welding transformer auto on/off system for 14 saving the power Day light/ optimisation by switching off lights Water pump VFD required to control the 16 pressure (U-1 pump house) Transparent sheet on workshop/dg/bc 17 galleries 10 8 Energy saving in lighting by concept of 18 separate transformer scheme for lighting Remarks under implementation under evaluation

9 Sl Job Description Rewind motor efficiency check and replacement with suitable one. Concept of permanent magnet in place of mag. Separator. Potential of saving to be calculated Power saving by providing starvation switch to prevent idle run in unit 1. Power saving in exhaust fan by new interlocking provided in cement mill section Power saving in cement mill section by introducing software interlocking for Optimisation of lighting load in Packing plant and cement mill unit 1 Power saving in crusher area Unit 1 by new software interlocking provided for aux. drive running time after stop of HT drive. Bag House U1 - Power saving scope through V/F Drive Expected Saving kw/hr. Achieved Saving kw/hr Remarks being procured proposal being finalised

10 Sl Job Description JOB LIST FOR UNIT-II Power saving by PID loops optimisation and 27 implementation in U-II Expected Saving kw/hr. 28 RABH dust transport through bulker 31 Plant lighting optimisation by providing on-off 29 controls at accessible locations in U-II Bag filter rotary airlock modification to 30 prevent idle run Achieved Saving kw/hr Cooling tower fan VFD Air conditioner optimisation in cement mill 32 and RABH load centres Bag filter fan VFD in crusher Idle run avoiding in crusher aux Crusher 2 shift operation Welding machine optimisation Compressors run hour control through DCS Remarks scheme under implementation being planned for execution

11 Sl Job Description Expected Saving kw/hr. Achieved Saving kw/hr. Remarks 38 Kiln shell cooling fan automation with temp Energy saving by Solar water Heater in G. 39 House Provision of false sealing at RABH L/C VFD in coal firing blowers in U VFD in reverse air fan in RABH SYSTEM being procured Apart from above, described next are few major initiatives, which paved way for mechanism to reap out the advantages:

12 Adopting EnMS ISO : One amongst pioneers in Indian cement industry to adopt prestigious EnMS ISO:50001 system. It orchestrated entire organisation towards movement. Structured steps of monitoring and awareness sourced novel ideas for implementation, which yielded coveted results. Distribution Transformers Load Rationalisation: Re-visiting loading pattern on distribution and power transformers of entire network suggested enough scope for rationalisation. 06 transformers switched off in entire plant, which helped in reducing losses ~ 35 kwh * 24 = 840 units/day. Planned schedule to switch on in a month time to avoid any degradation.

13 Utilities Load Optimisation: Re-view of plant area illumination as per Lux level and provision of onoff switches at accessible points. BC galleries, loading platforms and desolate equipment areas yielded maximum saving opportunities. Intense monitoring of compressors' utilisation & run-hours through DCS, equipment cooling and process water consumption, optimisation of HVAC with false ceiling provisions, use of VFD in P&V systems. Daylight utilisation wherever possible, use of transparent sheets in warehouses and workshops. LED lights replacing conventional ones for area & offices, Solar lights. Power less exhaust fans, switching off welding machines when not is use. Optimisation of auxiliary power consumption in DG House.

14 508, , , ,701 PRISM Improvement due to actions taken in utilities consumption: Utilities Consumption (kwh) Jan-15 Feb-15 Mar-15 Apr-15

15 Opportunity in Motors Efficiency: Identification of under loaded motors and arranging suitable replacement from available stock. Benefit ~ 37.5 kw. Replacement of Cooler ESP Fan SRIM motor (SPRS driven, limitation of operation above 70% rpm) with DC motor, which helped operation of fan below 50% rpm as per process requirement. Power factor improvement at motors' side. Process Optimisation: Plenty of scope was identified and worked out at different fronts for process optimisation to reduce specific power consumption. These are mentioned in above list. Resulted reduction in Sp. Power Consumption ~ 1.5 kwh/t of cement.

16 Time of Day Tariff (TOD) Utilisation: As per applicable MPERC tariff structure Peak hour surcharge - 5% surcharge Off peak rebate - 15% rebate Stopping equipment during peak hour and maximizing equipment run during off- peak hours results in reduced bills. Calculations and experience indicate ~ paisa/kwh on total day wise energy bills reduction, if plant operational requirement is met with production plan. Implemented the practice with participation of cross functional team. SOP prepared and circulated to all for awareness and controls. Actual monetary benefit ranges ~ Rs. 9 to 10 lac/month, depending upon capacity utilisation of plant.

17 RESULT Month Savings due to TOD tariff Remarks utilisation (Rs.) January 3,53,592 Experiment started February 10,54,302 March 11,05,545 April 5,04,841 One plant under shut down Plan reduced MD of U-II to ~36 MVA from 40 MVA, and for U-I 28.9 MVA from 32 MVA. Also helped to improve predictive maintenance and improve upon MTBF and MTTR.

18 Staggered Run of Equipment to Reduce Maximum Demand: Improvement in MTBF/MTTR helped to improve Overall Equipment Efficiency (OEE). This improvement invoked thought of staggered run of equipment as production requirement were now being met by even reduced run factor. Analysis of the process capabilities w.r.t. required production plan allowed staggered running of all sections except Kiln.

19 Contract Demand Reduction: Staggered run of sections, TOD tariff utilisation tends to reduce overall LF, which can affect unit rate, unless MD and CD of plant are in tandem. Energy efficiency measures, coupled with equipment efficiency improvement and process optimisation, created opportunity to reduce the Contract Demand (CD) of both Units. In U-I we could restrict the Contract Demand from 32 to 30 MVA and in U-II it was done from 40 MVA to 37 MVA. Reducing the CD not only improves upon Load Factor, but also has impact on the fixed cost, demand side reduction on load and overall GHG emissions.

20 U-I : Max Demand MVA Jan-15 Feb-15 Mar-15 Apr PLANT SHUTDOWN U-II : Max Demand (MVA) Maximum Demand

21 Optimisation of shutdown power: - Switched OFF 7 Nos of Distribution transformers out of 10 and one Power transformer out of Compressors running reduced by on demand run, as compressed air required for Girth Gear Lubrication system of Kiln Aux. only while brick lining. - Bag House fan power reduced by lowering the minimum speed limit from 110 to 50 RPM for shutdown period. - RABH dust transport circuit switched OFF immediately after plant shutdown. - PA Fan switched OFF and smaller size Emergency air fan taken into operation for cooling.

22 POST IMPLEMENTATION - RESULTS Measures taken showed up astonishing results. Few of them: - Clinkerisation power ~ 48 kwh/t of clinker, frequently touches even 45.5 kwh/t. - Cement grinding power ~ 24.2 kwh/t of cement, often comes as even 21.5 kwh/t. - Sp. Power Consumption ~ 63.5 kwh/t of cement, comes as low as 55.4 kwh/t of cement.

23 PAT SUCCESS BEE had given a tough target to achieve w.r.t. baseline study for PAT Cycle-I. Apparently extremely difficult to achieve the target, as projects, which PCL had intended & declared for execution, failed to realise due to unexpected failures & constraints. Estimated penalty due to non-achievement was looming around Rs. 15 crore.

24 PCL marched ahead with above explained energy saving measures and firm determination. Turnaround happened! Appointed Accredited Empanelled Energy Auditor TERI conducted M&V audit during May'15 and came up with following results: SEC : kcal/kg of equivalent product Baseline Target Achieved Implemented measures suggest issuance of E-Certs equivalent to ~ Rs 4cr. instead of penalty ~ Rs. 15 cr! Data submitted to BEE for review. This turn around happened for out of box measures implementation.

25 FORTHCOMING MEASURES - Process Fans Retrofitting: Study indicates that scope of ~ 900 kw saving is there with payback of < 1 year. -Small Projects on Process Optimisation: Areas have been identified for further load reduction to the tune of ~ 1.3 MW (both Units combined). These are under implementation & observation stage. -Cheaper Power purchase through Open Access: In quest of cheaper power, we have applied to our discom for allowing us power purchase through Open Access mechanism. Through IEX we can get cheaper power as & when available. Other feasibility of group captive mode is under evaluation, which may benefit us intensively.

26 FORTHCOMING MEASURES -Power generation from Waste Heat Recovery System: Plant has potential to generate power ~ 14 MW through WHRS. It is under evaluation and expect to implement in coming FY. -Unit -I Clinker Cooler Upgradation: Upgradation of U-I clinker cooler has not only potential to save ~ 2 kwh/t of clinker, but also can result benefit of ~25 kcal/kg of clinker. It is under evaluation for implementation.

27 WRAP UP Effective guidance and will full execution reaped out the benefits! Coming out of blues, once again PCL is on the path of being NUMERO UNO of Indian Cement Industry, in all respects. With implemented measures, continuous monitoring & analysis, corrections to meet desired results and forthcoming projects, we are sure to achieve < 55 kwh/t of cement on consistent basis. Truly said... " One Unit Saved = Two Units Generated".

28 THANKS For further information, please contact: Mr. B N Singh, Sr. G M (Tech), Prism Cement Ltd, [email protected] Mr. N. P. Singhai, Jt. G M (E&I), Prism Cement Ltd, [email protected]