Industrial ecology-based strategies to reduce the embodied CO2 of magnesium metal

Light-weight magnesium metal is used to displace heavy-weight steel and iron in automobiles and decrease CO2 emissions in the vehicle operation stage. This benefit is, however, significantly offset by CO2 emissions from high energy consumption in the magnesium production process. Thus, this study presents and assesses CO2 reduction strategies to mitigate the drawbacks of magnesium metal, based on the concepts of industrial ecology: industrial symbiosis with cement plant to utilize waste slag from magnesium production; industrial and urban symbiosis to utilize waste energy from urban area; and environmental supply chain management to purchase a feedstock with lower carbon footprint. These strategies can be used to reduce the embodied CO2 of magnesium metal by 5%, 31%, and 9%, respectively, compared to that of an existing magnesium metal. The industrial ecology-based strategies can be applied to produce low-carbon products and mitigate climate change.