SESA STERLITE LIMITED

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2 First Prize Aluminium SESA STERLITE LIMITED Smelter Plant - 1, Jharsuguda (Odisha) Unit Profile Sesa Sterlite Limited (SSL) Jharsuguda is a leading producer of aluminium products such as ingots, wire rods and billets, which cater to a wide spectrum of industries. The firm operates a 0.5 million TPA Aluminium Smelter Plant - 1 and 1215 MW Captive Power Plant supported by highly modern infrastructure at Jharsuguda, Odisha. In addition to this, commissioning of 1.25 million TPA Aluminium Smelter II expansion project at Jharsuguda has commenced. In its pursuit to achieve energy excellence and to meet PAT targets set by Govt. Of India, unit also successfully implemented Energy Management System (EnMS) and is certified for international standard ISO: since Feb Highlights of Energy Conservation Initiatives 1st Aluminium Smelter in Asia and second in world to be certified with ISO: for Energy Management System since nos. of energy saving projects have been implemented in the last four years generating saving of nearly 200 kwh/mt of aluminium production creating national benchmark. SSL, Smelter - 1 is a trend setter to adopt Reverse Osmosis for de-fluoridation of waste water with evaporation of RO rejects in solar ponds. This is unique & first of its kind in any Aluminium Plant to go for renewable energy in ETP in a RO plant. 17

3 SSL has successfully completed carbon foot print study by independent external agency First Climate and has taken a target to reduce CO 2 emission by 5% from baseline year FY by FY SSL has already achieved 2.3% reduction in CO 2 emission reduction from baseline Incorporation of Business Excellence models such as Six Sigma, QC, Kaizens, SGAs and Asset Optimization in energy management. People involvement and sharing best practices, internal & external benchmarking. Energy Consumption DESCRIPTION UNIT Annual production MT 5,26,612 5,42,496 Total electrical energy consumption/annum M kwh 7,768 7,870 Specific energy consumption (electrical) kwh/mt 13,762 13,563 Total thermal energy consumption M kcal 1,82,229 1,62,469 Specific energy consumption (fuel) M kcal/mt Energy Management System (ISO: 50001) Implementation As a responsible corporate SSL, Jharsuguda is continuously strengthening the energy management efforts for not only achieving PAT targets but also establishing benchmarking figures in energy performance. As per the potential of opportunity for improvement, target has been set for each Energy Performance Indicator (EnPI) and accordingly action planning has been done to achieve the same. All the EnPIs are mapped to employee s KRA for ensuring implementation of the EnMS at each level. MAJOR ENERGY SAVING PROJECTS IMPLEMENTED & INITIATIVES TAKEN ( ) 1. Modification in cell lining design to achieve improvement in energy efficiency in aluminium smelting The cell lining deign of pots has been changed which has reduced the cathode voltage drop and hence energy saving. The following technical inventions were introduced to cell like 18

4 1) Change in % of graphite in sealing paste 2) Change in % of graphite in cathode block 3) Change in collector bar composition 4) Change in geometry of collector bar 5) Change in thermal properties of side wall lining Unit witnessed drastic change in Cathode Voltage Drop (CVD) reduction from 349 mv to 285 mv in early stage which resulted in gain of kwh/mt. 2. Reduction of heavy furnace oil consumption in anode baking furnace. With aging of baking furnaces, different type of defects like flue wall bending, crack, uneven degassing gaps etc. are evolved. These problems in furnaces severely increase the false cold air ingress from atmosphere. As a result, the fuel utilization is affected significantly. The following improvement measures were undertaken to reduce the fuel consumption: Improvement initiatives: Preheating Curve optimization. Heating Curve optimization. Heat Loss & Cold Air Ingress Prevention. Effective Sealing of peep hole covers. Double Polythene Covering. Reduction in nozzle jamming. Replacement of cast iron ring by Peep hole cover design modification. refractory rings in Refractory wall. Refractory castable ring implementation. Scheduling the maintenance of thermocouple sheet. Fuel saving: 3,168 kl/annum 19

5 3. Other EnCon Initiatives in Current efficiency improvement in aluminium smelting pots from 93.2 to 93.7%. Reduction in average pot voltage from to V by taking different improvement initiatives(riser drop reduction, CVD reduction by modifying cell relining design, clamp drop reduction) Reactor Venturi modification and air chamber plug modification and cleaning of all air slide air chamber. BTAP unloading time reduction resulting in power consumption reduction of dedusting fan and also LP compressor running hour. Automatic switching of lighting through PLC. Installation of solar energy operated street light in parking area Installation of energy efficient motor for Hopper Blower. Modification of Lighting Scheme for 6.6 kv Distribution Room - 2. RPH pump energy consumption optimization. Replacement of MH lamps with induction lamps Interconnection of spray and main jockey pump header. Number of HP compressor running optimization done (5.6 to 5.01) by pressure control and process optimization. Interlock between ungrouping and grouping scrapper conveyor and reduction of idle run time. Overhauling of Cooling towers and VFD installation in CT fan motor and pumps ENVIRONMENT INITIATIVES SSL has adopted best in class technology for environment management system for monitoring and control. As a responsible corporate citizen SSL has adopted eight policies for sustainable development. The 8 signed policies are: HSE Policy, Water Management Policy, Energy and Carbon Policy, Biodiversity Policy, Human Rights Policy, Social Policy, Supply and Contractor Management Policy, HIV/ AIDS Policy, Stake holder engagement Policy. SAFETY Unit follows the following best practices in safety. Best Practices of Safety Visitor Management at Workplace. Senior Management safety walks down and audit. Yellow and Red Notices for safety and environment violations. Entry passes for High Risk Areas. Reporting of Unsafe Act and Conditions by each employee in portal. On job training and class room training for safety awareness. Focus on Behaviour Based Safety - BBS & STOP audit Implementation of Change Agents for Safety, Health & Environment CASHe projects. 20

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7 Certificate of Merit Aluminium SESA STERLITE LIMITED Lanjigarh (Odisha) Unit Profile Sesa Sterlite Ltd is one of the world s largest diversified natural resource companies. The Alumina Refinery at Lanjigarh is having 1 million tonne per annum production capacity which includes other associated facilities such as - a 75 MW Captive Co- Generation Power Plant (CCGPP), 65 kilometer Water Pipeline from Kesinga to the Plant and 16 kilometer long Railway Corridor connecting the Refinery to nearby Ambodola Railway Station. The Company is planning to expand the Plant from 1 million to 6 million TPA. This is the only Alumina Refinery in the Country having successfully implemented Zero Discharge System and actively working on the Zero Waste Projects for the first time across the Globe. The final product is smelter grade calcined alumina which is being dispatched to group companies situated at Balco and Jharsuguda locations. 22

8 Specific Energy Consumption Toe/Ton Toe/ton Note: In FY from Dec 12 to Mar 13 and in FY from Apr 13 to Jul 13, alumina refinery was under shut down due to scarcity of major raw material (bauxite). Because of this, energy consumption is at higher side in these years Energy Conservation Achievements 1st metal and mining company in the world certified with ISO: 50001:2011 for Energy Management System. Around 78 energy saving projects have been implemented in last three years generating saving of more than 0.5 GJ/MT of alumina production Development and Implementation of Innovative and Breakthrough Energy Efficiency Improvement Projects SCADA based Energy monitoring & Management System (EMS) is implemented. First refinery in the world which prepared a roadmap to achieve benchmark energy consumption which is as follows. Roadmap to Achieve Benchmark Energy Consumption 23

9 Energy Management System Implementation Management Commitment Major Energy Conservation Projects Project No. - 1: Heavy Furnace Oil Consumption reduction in Calcination unit of the Alumina Refinery. Description: In energy terms Heavy Furnace Oil (HFO) consumption in calcination unit constitutes around 30 % of refinery s overall energy consumption. HFO is used in calcination process to maintain the temperature in calciner unit up to 1100 C, at this temperature the Hydrate Cake (Al 2 O 3.3H 2 O) loses all the attached water molecules and Alumina (Al 2 O 3 ) is formed. The Hydrate Cake, which is the intermediate product of alumina refinery, is formed by filtering the aluminum hydrate slurry using horizontal pan filters. After the filtration process some surface moisture (7-9 %) remains in the hydrate cake. The Hydrate cake surface moisture ( ) 24

10 was reduced from 7 % to 5.5 %. The specific HFO consumption ( ) in calcination was reduced to 70.5 kg/t. In addition to that some other benefits were also realized during the project implementation. The specific energy consumption got reduced from 34.5 kwh/t to 32.1 kwh/t. Project No. - 2: Control of Common Heater (Trim Heater) Outlet Temperature in Auto mode. Description of the energy conservation measure: Reducing energy loses by reducing the standard deviation of outlet temperature of Trim Heater by making it to run in Auto Mode. Root Cause: When Temperature controller (TIC 0426) tries to control the outlet temperature (TI 0426), the pressure controller (PIC 0001) operates in other way creating cyclic fluctuation in Outlet temperature with higher SD. Solution: If a de-super heater works between the PIT and PCV to reduce the steam temperature down to 140 C (Saturation temp.) then it will help to minimize the pressure fluctuation and also improve the recovery of latent heat Project No. - 3: Energy Conservation by De-Staging of Boiler feed water pump. Root Cause: Three nos. of BFPs were in operation to feed water to 2 nos. of boilers. Out of three, one of the BFPs was running in partial load. Pressure drop across the FRS station was 34 bar. Approach: Reduced one stage of pump. Result: Pressure drop across the FRS reduced to 20 bar.bfp header pressure reduced to 95 bar. Reduction in power consumption by 100 kw. 25

11 Project No. 4: Modification of motor pulley size in DBNK PDS transfer pumps. Description of the energy conservation measure: Reducing energy loses by reducing pumping capacity and increasing the suction head by maintaining high level. Root Cause: Pump G24 PU 0025, 26 are designed to handle 1100 m 3 flow which is not required to the existing conditions, i.e. having the PDS tanks at high level necessitates having pumping elevation of only 4 to 5 m. (including line losses). Solution: It is quite adequate to have the pumping capacity reduced to 600 to 700 m 3 /hr flow, as unit is maintaining tank level high (to provide adequate residence time). Major Projects Related to Safety and Environment 1. Robotic Cleaning of Equipment and pipe lines to minimize human exposure 2. Mobile and static vacuum cleaning systems to minimize dust generation 3. Acoustic and new silencers for noise control 4. Dry Fog system has been provided to control dust emission in bauxite crusher house & at different transfer points. Water spraying arrangement at bauxite stock piles has been provided by the unit. 5. Wet scrubber system has been installed to control lime dust in lime handling area. 6. Dry Fog System to control the dust emission in its crushers and transfer points and water sprinkler for coal storage yard 7. Dust extraction systems with bag filter are provided to control fugitive emissions from transfer points, conveyers and silo of alumina handling area 8. Modification of ESP's attached to Coal fired boiler no. 1, 2 & 3 in power plant has been completed for emission reduction and the PM concentration after modification is well below the target (100 mg/nm 3 ) 9. Online monitoring system has been installed for continuous monitoring for exit concentration of Sulphur di-oxide, Oxides of Nitrogen and Particulate Matter and also sampling ports have been provided. 10. Water consumption per ton of alumina has been reduced from 18.8m3 to 3.0 m 3 /Ton of alumina 11. All the waste water generated in the process is being recycled and reused in the process again. 12. Installation of two STPs, one 360 KLD capacity STP inside the Plant and 150 KLD capacity in the Staff Colony. Treated water is being used for Horticulture purpose 13. Celebrated World Environmental Day (WED) and Vanamahotshav for environmental awareness of local villagers 26

12 14. Planted nos. of sapling planted in 37.2 ha. area for Green Belt Development 15. Production of cold setting bricks & blocks by utilizing of red mud and fly ash 16. Used fly ash instead of soil to prepare dyke wall Energy Policy 27