How to Improve the Environmental Efficiency of the Hall-Heroult Process While Producing and Using Carbon Anodes

Abstract

Carbon anodes will likely stay as the primary reduction medium in aluminium smelting for years to come, despite the ongoing development of inert anodes. This is due to the excess production of petroleum coke as a by-product of hydrocarbon distillation and the CO2 profile of energy production, making inert anode technology likely best suited for regions with hydropower as opposed to e.g. coal power. This means that industry must increase the environmental performance of the conventional Hall-Heroult process. We list several levers by which this can be achieved from an anode producer’s perspective. These levers include: Direct, examining factors to increase the efficiency of anode productionIndirect, examining factors that increase Potline efficiency and fuel consumption, examining potential to use renewable materials in anode production.We conclude that there is still has a lot of potential to reduce the carbon footprint of the Hall-Heroult process. The presentation is a combination of a literature review, and several industry examples.