Magnesium production and automotive applications: Life-cycle analysis focussing on greenhouse gases

Abstract

For a few years now, magnesium supply has been dominated by Chinese producers who provide about 80 % of primary magnesium in the world. The Pidgeon process as used there has been shown to have high CO2eq emissions per kg pure magnesium compared to elec-trolysis technology, which is used in other magnesium producing countries. As production processes in China have changed significantly concerning efficiency and energy consumption, we surveyed Chinese magnesium producers and analysed the data with regard to gaseous energy carriers, process improvements and resulting greenhouse gas emissions. We compare our results to the performance of magnesium from the electrolysis process. Magnesium is used for various automotive parts. As a light material it lowers CO2-emissions at the tail pipe, though its production is more energy intensive than for aluminium or steel. We discuss this by showing break-even distances from the use of two different magnesium components in comparison with other materials.