Chapter 20 - Life cycle assessment of iron ore mining and processing

Abstract

Mining of iron ore is a highly capital and energy-intensive process. Life cycle assessment of the mining and mineral processing of iron ore in Australia was carried out in this chapter using SimaPro life cycle assessment software as a case study. The environmental impacts considered in the study were embodied energy and greenhouse gas emissions, while the functional unit was 1 tonne of iron ore, ready for transport to downstream metal extraction and refining facilities. Inventory data for these processing stages were calculated by the author. The estimated greenhouse gas emissions were 11.9 kg CO2e for mining and processing 1 tonne of iron ore. The embodied energy values were 153 MJ/t ore for iron ore. The results showed that loading and hauling made the largest contributions (approximately 50%) to the total greenhouse gas emissions from the mining and processing of iron ore. These results indicate that efforts to reduce the greenhouse gas footprint of iron ore should focus on loading and hauling stages. Further advances in diesel engine technology for loading and hauling applications could be expected to assist into reducing the carbon and energy footprints of iron ore mining. The boundary has been extended to iron and steel making and the greenhouse gas emission of iron ore to steelmaking has been reported for various scenarios.