Cyanide-free leaching technology launches

20th June 2019 By: Esmarie Iannucci - Creamer Media Senior Deputy Editor: Australasia

PERTH (miningweekly.com) – The Commonwealth Scientific and Industrial Research Organisation (CSIRO) has licensed Perth-based Clean Mining to sell and distribute a new cyanide-free gold processing technology.

The technology was developed over more than a decade by the CSIRO and replaces cyanide with a safer, less hazardous chemical reagent called thiosolphate.

The inorganic compound helps to dissolve fine gold out of ores into a solution, which can then be recovered through further processing.

Clean Mining MD Jeff McCulloch says that currently around 75% of gold extracted from ore is processed using cyanide or mercury, which are toxic to both humans and the environment.

“Eliminating cyanide and the associated tailings dams from the gold recovery process is a game-changer for the sector and, importantly, for the communities where gold miners operate,” he says.

Clean Mining will initially target small- to mid-scale miners that can benefit from the cost-effective leaching ore processing solution, which will include a plug-and-play plant that can be customised and scaled to meet individual needs.

The technology is suitable for greenfield and existing mines, as well as for locations where cyanide could not be used or is banned.

“Clean Mining also offers a solution for large-scale gold miners using cyanide that aspire for greater levels of environmental, social and governance standards,” McCulloch says.

McCulloch says that the company has already fielded interest from miners seeking to unlock previously uneconomic or stranded deposits, as the solution does not require financial investment in a large-scale plant, and mitigates hazardous chemical risks.

“Our technology enables all miners to eliminate the use of toxic chemicals which, put simply, is the right thing to do.”