Meeting of models helps reduce toxic waste

From Process magazine, October 2007:
An unfortunate twist of chemistry means that one of the earth’s most beautiful metals requires one of the planet’s most deadly compounds to extract it from an ore body: gold mining relies on the use of cyanide to dissolve gold into solution so it can be recaptured as pure metal.
The inevitable by-product of this process is a cyanide-containing slurry that is discharged into specially constructed tailings dams, where the solids settle out and the solution can be reclaimed for reuse.
The recently introduced International Cyanide Code, which sets voluntary guidelines on the quantity and concentration of cyanide being released into tailings dams, recognises the importance of reducing cyanide discharge.
Parker Centre researchers at CSIRO Minerals have taken a novel approach to reducing discharge and ultimately meeting new standards. Using computer modelling, the team investigated a method of reducing cyanide discharge while increasing the amount of water reclaimed and reducing the need for other reagents, such as lime, used in the gold extraction process. Read more. (pdf file, page 9)