Opportunities for sustainability improvement in aluminum industry

The aluminum consumption in India of 2.5 kg per capita is way below the global average of 11kg per capita. In the future, India will require additional annual consumption of 16 million tons of aluminum. Due to the energy-intensive nature of aluminum production coupled with its projected growth, there are sustainability concerns for this industrial sector. This paper examines some opportunities available for sustainability improvement in an existing aluminum plant using coal-based electricity. An industrial sustainability index (ISI), as previously developed by the authors, is here to quantitatively evaluate the magnitude of sustainability improvement through a natural gas-based combined cycle (NGCC) power generation. Two modes of sustainability improvement are examined: (a) NGCC with surplus power generation and (b) NGCC with doubling of production capacity. It is observed that the ISI values can be increased by 5 to 6 times through the above modes, as compared to the existing model. The investment required for such sustainability improvement is expected to be less than that required for setting up a totally new plant. The direct carbon emissions for the existing plant are nearly 6.4% of the total carbon emissions, which may be eliminated by adopting new smelting technology now available, with the further possibility of sustainability improvement.