Australian aluminium industry under threat

A high dollar, low prices and Asian competition are threatening the industry with older plants in New South Wales and Victoria under threat of closure.

The debate about the future of the industry often concentrates on the high energy usage associated with aluminium production. The joke description of aluminium as congealed electricity is never far away. It is true that a lot of energy is required to make Aluminium. CSIRO calculate that the embodied energy for aluminium is 211 GJ per ton compared to 22.7 GJ per ton for steel. This huge difference in overall energy required to produce the metal helps explain the enormous difference in the scales of the two industries last year, nearly 1500 million tons of steel was made in the world compared to 40 million tons of aluminium.

Of course, aluminium is over 3 times lighter than steel which means that energy savings can be made over the lifetime of the metal’s use if aluminium replaces steel in transport. Also, the overall energy picture looks much healthier if your energy source is hydroelectricity.

Some argue that only countries with hydroelectricity should make aluminium. It would not be a very healthy economic solution for Australia and would reduce the country to being a supplier of raw materials. In many countries around the world, aluminium smelters provide the impetus for construction of power stations, as the investors know that the smelter will provide 24 hour base load, 365 days per year.

Aluminium is made by dissolving the oxide into molten salts, at around a more modest 960°C and applying a current to help break down the oxide. This is the Hall Heroult process which dominates world aluminium production at the moment. The process typically loses around 50% of the incoming energy as low grade heat which is due in part to the fact that the salts required to dissolve the oxide are so corrosive that there no practical way to keep the heat in. There are also great challenges in the anode and cathode technology in the Hall-Heroult process that result in large resistance losses.

Research and other projects around the world are focused on lowering the energy associated with aluminium production. Australia can take the lead on these developments. The current business environment appears to be very negative. But opportunities for innovation abound in times of crisis. Given Australia’s great natural advantages in terms of raw materials, I see some light at the end of the tunnel.