Turning an aluminium byproduct into ceramics
A group of designers at the Royal College of Art designed ceramic pieces made of Red Mud, a byproduct in the making of aluminium.
Red Mud is also known as Bauxite Residue, and is a byproduct of refining bauxite ore into alumina, the precursor of aluminium. The red colour comes mostly from iron oxide, better known as rust. Roughly 2.5 times the amount of Red Mud is made for each part of aluminium. Close to 150 million tonnes of Red Mud are produced every year and are left in giant pits. The material is very alkaline, and just leaving it has huge impacts on the environment.
Designers Guillermo Whittembury, Joris Olde-Rikkert, Kevin Rouff and Luis Paco Bockelmann aim to find a solution for this waste, by turning it into ceramics. Having sourced the Red Mud from the south of France with help from Alteo, one of the first alumina refineries in the world, the designers then worked closely with KU Leuven and Imperial College London to explore the potential of the material both as a ceramic and as a geopolymer building material. Through hundreds of tests, they developed their own clay bodies, slips, glazes, and concretes, all made with the material.
The main risks of the material are the alkalinity and the fine particle size, but the designers use this to their advantage. The fine particle size makes it possible to slip-cast the material into delicate forms, while the alkalinity allows for the use of the material as a geopolymer concrete, which could lead to architectural uses in the future.
The ceramic glaze is also developed using the industrial waste, thanks to the abundance of metal oxides. The ceramics are neutralised when fired so they are safe to eat and drink from.
The aim with these pieces, the designers explain, was to make people at once aware of the impact of materials taken for granted in the everyday, like aluminium, and to see the potential of their byproduct counterparts. Joris, one of the designers, explains: “We need to reevaluate the term ‘waste’, which is in reality an asset that can and should be used.”
Photos: Guillermo Whittembury, Joris Olde-Rikkert, Kevin Rouff and Luis Paco Bockelmann