Researchers in Brazil have discovered that the ash produced by burning coal can effectively remove heavy metals from the effluents generated by the same industries that burn it. The ash, a waste product generated in coal-burning thermoelectric power plants, “has the property of retaining heavy metals like manganese,” explained Paulo Sérgio Soares, a researcher at the Clean Technologies Service of the Mineral Technology Center, which is connected to the Brazilian Ministry of Science, Technology and Innovation.

“All of the liquid used in the mining process becomes contaminated. We carry out a first phase of chemical treatment. In the second phase we incorporate the ash, which reduces the wastes to an acceptable level, before we release the liquid back into the environment,” he told Tierramérica.

Up until now, the coal ash was disposed of or used in the cement industry.