Abstract:Life cycle assessments (LCA) of magnesium smelting process by Pidgeon method and vacuum carbothermic reduction method were carried out using 1 t magnesium ingot as functional unit to study environmental load and energy consumption of processes including raw material mining, material preparation, material consumption, energy production, and pollution discharge. On the basis of deriving relevant parameters of LCA, Pidgeon process and vacuum carbothermal reduction method were compared in terms of resource and energy consumption, gaseous pollutant emission and environmental impact. Respective environmental load and energy consumption characteristics of two process were clarified. By comparison, carbothermic reduction method has obvious advantages over Pidgeon process in terms of resource saving, energy conservation, environmental protection and sustainable development.