Hydrometallurgy Cyanide Heap Leach - some dangers.


The science of Turning rocks into Metal. Crushing, grinding, concentrating, pre roasting and smelting of ores into valuable metallic products and biproducts. Covering Hydrometallurgy, Pyrometallurgy, leaching, the environment, thermodynamics and science and energy.

Moderator: Philski

Post Reply
User avatar
Posts: 514
Joined: Tue Sep 25, 2012 2:21 pm
Location: Sheffield Tasmania

Hydrometallurgy Cyanide Heap Leach - some dangers.

Post by Philski » Thu Feb 20, 2014 11:14 pm

HydroMet is the most common way to produce high purity metals. It exceeded Pyrometallurgy in many ways and offers benefits like in situ permanent pad leaching and better environmental outcomes. However it is also takes more time to leach 200 days plus. And in many cases more energy. This isnt always the case and leach times can be quite fast given optimum temp and pressures. Gibbasite into alumina in Lye. but it does have some dangers. Cyanide for one.

And, things do go wrong. Here in Tasmania we had 2 leach pads rupture at different sites and spew toxic cyanide into our environment. And we still use them, They are safer today apparently.

The second pad ruptured behind Beaconfield in the early 1990's.

The system is still there today and has not had a leak since? the Lea river alluvials for Torque Mining go in this leach pad. http://epa.tas.gov.au/documents/proto_resources_noi.pdf
Henty Gold mine and many others exist in Tas.

There are also dangers of ground water contamination.

Another on the very near horizon is deep sea in situ leach mining. They will eventually drill the ocean floor, frack the rock then pump acid down into the rock, dissolve the minerals, then flush it all out with sea water to make the solute come out and then plug it. So it has eco dolphin appeal.

acid drainage link:
http://www.mrt.tas.gov.au/pls/portal/do ... REPORT.PDF

Post Reply