Jungfrau Zeitung – Mining waste could alleviate sand shortage
research | April 16, 2022
Due to global urbanization and the associated tree boom, sand is becoming scarce. A team from the Universities of Geneva and Queensland submit a report that sand recovered from mining waste could alleviate the problem.
Waste from mining could counteract sand shortages.Photo: Photo: Keystone/Jean-Christophe Bott
After water, sand is the world’s most used natural resource. Their consumption has tripled in the last two years to an estimated 50 billion tons per year – and the demand is growing exponentially, especially because the construction industry uses a lot of sand. However, the massive extraction of natural sand deposits in coastal areas, rivers and lakes has serious consequences for the environment.
Ore sand as an alternative
The researchers from the University of Geneva and the Sustainable Minerals Institute (SMI) at the University of Queensland in Australia are now presenting the potential of an alternative that has so far hardly been used – the so-called ore sand, as the institutions announced on Tuesday. Ore sand is a sand-like material that is a by-product of mining mineral resources. According to the report, an estimated 30 to 60 billion tons of mining waste is currently generated annually, making it the largest waste stream on earth, the researchers said.
“Separating and reusing the sand-like materials before they enter the waste stream would not only significantly reduce the volume of waste, but could also create a sustainable source of sand,” said co-author Daniel Franks, according to the release. The researchers examined the potential of ore sand using the example of the Brazilian company Vale. Vale is one of the largest iron ore producers in the world. He operates more than twenty iron ore mines in Brazil, which generate millions of tons of mining waste every year.
Hard gravel is often mined during mining.Photo: Photo: Keystone/Thomas Hodel
For the analysis of ore sand, the researchers took samples from an iron ore processing plant in Vale in the Brazilian state of Minas Gerais. They demonstrated that part of the material flow that would otherwise end up as waste could be used as a substitute for sand in construction and industry. For example, sand is also used to industrially produce glass or ceramics. If these results translate not just to iron, but to other mineral ores as well, there is potential for a significant increase in global mining waste, researchers say.
In terms of life cycle assessment, it was shown that ore sand could potentially lead to a net reduction in carbon emissions in sand production. However, the researchers emphasize that the emissions are largely dominated by transport. The proximity and the type of transport from ore sand production sites to the places of demand therefore play an important role with regard to the potential for climate protection.
China could meet one billion tons of sand demand
According to the report, there is a sufficiently high demand for sand at almost a third of all possible ore sand mines within a fifty-kilometer radius. Researcher Daniel Franks added that China could potentially meet a billion tons of its sand needs with ore sands.
The team presented the results of the study at the 5th United Nations Environment Assembly (UNEA), as the University of Geneva noted. A new UN resolution calls for a strengthening of scientific, technical and political knowledge about sand in order to support global strategies and measures for the environmentally sound extraction and use of the natural resource.