BHARAT ALUMINIUM COMPANY LIMITED

Transcription

1 First Prize Aluminium BHARAT ALUMINIUM COMPANY LIMITED Korba (Chhattisgarh) Unit Profile Bharat Aluminium Co. Ltd. (BALCO), a Vedanta Company is a part of Vedanta Resources Plc, a London Stock Exchange listed -FTSE 100 Global Metals & Mining major which is globally diversified natural resources major with interests in Zinc, Lead, Silver, Copper, Iron Ore, Aluminium, Power and Oil & Gas. Through various subsidiaries, its foothold spans across India, Zambia, Namibia, South Africa, Liberia, Ireland and Australia. Bharat Aluminium Company Ltd. (BALCO), under the umbrella of Vedanta Resources Plc, has been closely associated with the Indian aluminium industry, playing a pivotal role in making aluminium, which has myriad uses ranging from household and industrial requirements to aerospace applications. It is well positioned in the key core sector industries, has a strong track record of performance and is among the fast growing groups in India. The company started its business in the year 1965 as a Public Sector Undertaking (PSU). In the year 2001, GoI divested51% equity and management control in favor of Sterlite Industries Limited (Vedanta). BALCO s principal strength lies in its dedicated employees across the competencies of mining, manufacture, research, quality, strategy, finance, marketing, environment and people management. The company is enriching the quality of its human resources through selective recruitment, training, motivation, delegation, reward and recognition. BALCO has its own captive Power Plant, captive mines at Mainpat and Kawardha. Mining is basically of open cast semi- mechanized type. 19

2 Energy Consumption Description of the energy conservation measures Various projects were undertaken to reduce specific Power Consumption in Potline- 1. The major projects are listed below- Project 1 Conversion of Split Beam to Single Beam Balco Potline-1 has 288 Pots with Split Beam Design (i.e. 20 Anodes suspended on two beams each).to improve the Pot performance & Efficiency, the split beam design of the Pot was converted into single beam by coupling both the suspension mechanisms in all 288 Pots. Existing Anode Jacking frames were also modified to facilitate Beam Raising Operation in pots. The result was stable operation of Pots with reduced Noise, reduced Voltage Fluctuation, reduced operating Voltage and improved Current Efficiency. 20

3 Challenge- Operation of Pots with reduced Voltage fluctuationand Noise. Both parameters were high and the Split Beam design of Pots was a major contributor. Result- Reduction in Specific Energy Consumption by 66 kwh/mt Project 2: Increase in Anode Slot height - Saving of 13 kwh/mt During electrolysis the gas produced at the anode surface forms bubbles, which cover a significant part of the active anode surface area. Being nonconductive, this gas layer increases the resistance contributed by the bubbles. Slotted anodes help in escape of gas which ultimately leads to reduction in Specific DC power consumption and increased current efficiency. Slots are configured in two ways Longitudinal or Transverse. Transverse slot from 174 mm to182 mm Longitudinal slot from 200 mm to 207 mm Project 3: Reduction in Stub to Carbon Voltage drop Saving of 99 kwh/mt Stub to Carbon (STC) drop is the measurement of voltage drop due to stub and cast iron in Rodded anode. Higher STC results in higher power consumption and increased current efficiency in pot room. Following best practices were adopted which resulted in reduction in stub to carbon voltage drop Improvement in Stub cleaning practices Improvement in Welding quality Improvement in Stub cutting practices Optimization of chemical composition of cast iron With the implementation of above projects, potline current efficiency improved and Specific Energy Consumption reduced by kwh/mt resulting saving of Rs Cr per year 21

4 Major Energy Conservation initiatives taken in FY Achievement of Annual Energy Savings in S. Project description Electricity Fuels* Total savings Investment No. (Rs. Lacs) incurred (Lacs Coal F.Oil after on the kwh) (tonnes) (kl) deducting project investment Rs. (Lacs) 1 Reduction in specific energy consumption due to a)conversion of Split Beam to Single beam in Potline b) Reduction in stub to carbon drop from 130 mv to <100 mv c) Increase in anode slot height 2 Reduction in Auxiliary Power Compressed Air line integration between potline-1 and potline-2 3 Reduction in HFO consumption from litre/anode to 48 litre/anode in Bake-oven 4 consumption through modification in circuit of ventilation motor in SRS 5 consumption from NCRM ATLAS compressor 6 consumption through fabrication of launder covers in Casthouse 7 reducing the idle running hours of bag filters, shot-blast turbines, optimising bag filter fan motor cooling tower fan motors in rodding 22

5 8 minimizing the Idle Running hours of NCRM feed pump, NCRM filter pump,hydraulic pump of NCRM and cut up line, Cut up line chopper, NSL blower 9 Optimization of laddle heating cycle for automatic start-stop in rodding 10 automation of Main Mill blower and furnace burners to reduce ideal running hours in Casthouse 11 installation of Cast Bar pyrometer to control mill load in casthouse 12 Installation of temperature sensor in water line of Novelis cooling tower to automate CT fan operation in Foundry 13 Installation of 24 hour cyclic timer in HFO tank area and BC bay roof light in foundry 14 Installation of stop push button in Novelis casting operator desk for optimizing idle running hours of cooling tower centrifugal pump in foundry 15 minimizing the Idle Running hours of Vacuum group,g-group ID Fan Speed & Heater Setpoint reduction,de-1 ID Fan Speed regulation, HTM Secondary Circuit 2 (Kneader circuit) pump stoppage in shutdown in GAP 23