Sea water has been used, to neutralise bauxite residue at the Queensland Alumina Limited (QAL) refinery for more than 30 years. It has also been used at the Rio Tinto Yarwun refinery, since its commissioning in 2004. While the initial use of sea water was driven by a drought, the benefits of effective neutralisation of any residual alkalinity in the slurry through reaction of the alkalinity with the magnesium and calcium in the sea water were soon apparent.
