The University of Queensland’s Sustainable Minerals Institute, Rio Tinto, and Queensland Alumina Limited are preparing to enter full-scale trials of a new technology that converts red mud to soil that can be used for plant growth.
The University of Queensland made the announcement last week, noting that the process may well be able to transform the over 4 billion metric tons of red mud waste. Australia is behind only the People’s Republic of China in yearly red mud production.
According to lead researcher Longbin Huang, the process will produce a substance that will work well within a wide variety of environments.
“The technology is a process to utilize functional and cost-effective engineering inputs, either organic or minerals, to accelerate in situ microbial bioweathering of minerals and soil pedological and ecological processes in the amended wastes, towards the formation of functional growth soil, that is compatible with ecological attributes of native/exotic plant species and communities.”
“The in situ eco-engineering of mineral wastes into soil largely offsets the need for excavating and transporting large volumes of natural soil resources from non-mined landscapes, thus achieving a great financial advantage while improving environmental quality expected,” Huang continued.
“This game-changing technology is expected to enable mining operators to commence progressive rehabilitation of tailings and mineral wastes, without the reliance on expensive and hard-to-come soil resources excavated from off-sites.”
Huang noted that the salinity and alkalinity of red mud makes the process difficult. However, the process is more sustainable and cost effective than conventional methods of handling red mud.
“The technology developed so far is field-operable at large scale and transferable and adaptable across sites, based on the specific mineralogy of tailings, the availability of local economic and renewable resource, and climatic conditions.”
Rio Tinto and QAL provided US$3 million to the University of Queensland to develop the process. The eight-year project has taken the process from proof of concept to the present developments.