Mining the waste: prospecting valuable residues optimising processes with modern technology sustainably remediating legacy sites
Abstract
Prospecting valuable residues
Abandoned waste from closed mines or past operations may contain profitably recoverable commodities:
-when the market price of the commodity increased significantly since mine closure,
-when processing technology improved significantly since mine closure,
-when another commodity present in the ore was not recovered and thus sent to waste, because it was not of commercial value at the time. This is especially relevant for some high-tech elements.
Abandoned waste rock heaps (halda) and processing waste (tailings) can be prospected and re-evaluated with modern on-site analysis and sampling equipment.
Optimising processes with modern technology
Reprocessing mine waste is attractive because it skips most of the mining and crushing costs. The operator can therefore focus on investment in processing technology and in site management.
It allows also earlier profit generation, with lesser site development. This allows keeping funds for proper site closure.
Sustainably remediating legacy sites
Reprocessing waste will leave a similar amount of residual waste, generally more reactive and with potential environmental impacts. A sustainable management of this residual waste is therefore a mandatory part of waste mining.
Many abandoned mines are potential environmental hazards. In most cases, there is no economical option for remediation. Mining again abandoned waste can provide the required funds for sustainable waste management and site remediation.
Origin : Files produced by the author(s)