Canadian Magazine

Mining
Canadian
Spring 2014
Magazine
B.C.’s Black
Gold: Coal
Canada Post Publications Agreement Number: 40609661
Mine tailings contain valuable
precious metals…if recovered
N
anoStruck Technologies Inc. is a Canadian company with a suite of technologies
that remove molecular sized particles
using patented absorptive organic polymers.
These versatile biomaterials are derived from
crustacean shells or plant fibers, depending on requirements of their usage. Acting
as molecular sponges, the nanometer-sized
polymers are custom programmed to absorb
specific particles for remediation or retrieval
purposes.
The company’s technology can be used to
recover precious and base metals from mine
tailings. By retrieving valuable metals from old
tailing dumps, the company’s NanoMet solutions boosts the value of existing mining assets
and reduces the need for new, costly and potentially environmentally harmful exploration
and mining.
By retrieving valuable metals from old tailing dumps, the technology boosts the value of
existing mining assets and reduces the need
for new, costly and potentially environmentally harmful exploration and drilling activities.
NanoMet technology process
The NanoMet process involves the application of three different technological processes
to recover precious metals from mine tailings.
The first is a typical, yet refined physical
process whereby tailings are ground down
to a fine powder, liberating flakes of precious
metals contained within them. Varying levels
of G-force applied to these powdered tailings
result in gravity separation of liberated precious metals. These metal elements are then
collected as a first stage recovery.
The second is a chemical process whereby the remaining tailings are treated using a
proprietary non-cyanide hydrometallurgical
process. An aggressive atmospheric acid leach
process is used; one that NanoStruck is developing for a wide range of minerals and ore
type applications.
The third stage involves a proprietary solvent extraction process whereby organic compounds including nanotechnology materials
are used to selectively retrieve precious metals out of the acid solution.
Why tailings?
The mine tailings industry is akin to the oil
sands industry. Oil companies had known for
decades of the value of oil in tar sands. Yet,
they waited until the last decade or so for the
oil price to be sufficiently high and the cost of
technology for retrieving oil from the sands to
become sufficiently low, before engaging in
significant oil sands exploration and processing activities.
Similarly, mining companies have known of
the value of precious metals left behind in processed ore after the initial mining activities.
These tailings have been retained in sizeable
tailing dumps (Google “mine tailing dumps” or
“tailing ponds” to get an idea). Now, with the
Innovations
Unlocking a Trillion
Dollar Idea
price of precious metals high, industry is waiting for the technology solutions to be sufficiently low and effective, to make the retrieval
process a very profitable one.
There was an estimated $20 billion worth
of precious metals left in mine tailings in 2012
alone. The total value of precious metals in
worldwide tailings is estimated to be US$1 trillion.
NanoStruck recently announced testing of
its Cyanide-free mine tailings treatment techniques and preliminary results show recovery
rates of gold from mine tailings to be much
higher than expected by industry observers.
The tests indicate that the NanoStruck techniques can recover as much as 96 per cent of
9.1 grams per metric ton, or 0.32 ounces per
ton, of gold contained in representative gold
tailings samples.
When the NanoStruck techniques were
applied to tailings that had been previously
roasted at the source site, the recovery rate
was 88 per cent; multi-fold higher than previous attempts by other companies using alternative technologies such as cyanide leaching.
From the same already-roasted sample,
for example, conventional Carbon In Leach
(CIL) processes had resulted in less than 10 per
cent recovery of gold. The volume of tailings
at the source site, which is owned by an unrelated third party, is estimated to be between
450,000 tons and 500,000 tons. NanoStruck
is in discussions with the owners of the source
site regarding potential contracts for processM
ing the mine tailings at the source site.
For more information:
NanoStruck Technologies Inc.
Tel: (905) 813-0900
Email: [email protected]
Web: www.nanostruck.com
Canadian Mining Magazine
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