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10/31/07 1
Nichromet Extraction Gold Technology
10/31/07 2
Nichromet Cyanide-FreeGold Extraction Technology
Nichromet Extraction Inc.3700, Lac Noir StreetThetford Mines (Qc)418-423-7247www.nichromet.com
A green alternative to the classical cyanide
approach
Give access to oresrefractory to cyanidation
Less costly than theclassical processes withoutenvironmental mortgage on
residues
Can be implemented as modular plant
Vision
Develop an economic alternative to classical cyanide process for gold extraction, while keeping a sustainable development approach minimizing the impact on the environment.
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Overview of the Process
Sulphides Ores
Controlled Oxidation
AcidLeaching
Base Metals
Halogens Treatment
Sulfuric Acid
Precious Metals
Inert Tailings
Nichromet Process Flowsheet
REALISE PAR
David Lemieux
PAGE
1 SUR 1
DATE DE MODIFICATION
2013-02-12
TITRE
Sector 00 : General Flowsheet
# DE DESSIN
Bag House
To Atm
To Arsenic Stabilization
Copper Extraction
ChlorinationReactor
Deaeration Tank
Larox filter
Pregnant Brine
Holding Tank
Carbon to Gold
Recovery
Reverse Osmosis
Polishing Filtration
Na2CO3
Ca(OH)2
ElectrolysisCell
OxidationFluidized Bed
Arsenic Scrubber
SO2 Scrubber
Concentrate
From Concentrtor
Tailings
HypohalidesHolding Tank
Concentrated Brine
Holding Tank
IronPrecipitator
Carbon In Column
Gypsum
Iron Precipitation
Copper Cementation
Blister Copper
IronRemoval
CalciumPrecipitator
Polished Brine
Holding Tank
Hematite
OxidationPre-Treatment
CopperRemoval
Gold Circuit
Advantages Over Cyanide
Faster Reaction Time Process time of few hours instead of few days
Legal issues Cyanidation has been banned in many countries
and some States in USA (ex:Wisconsin)
Extraction of silver and PGM if present
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Environmental Advantages
No cyanide No tailings pond (elimination of spillage hazard) No liquid effluent Solids residues devoided of sulphides and base
metals No acidic lixiviate or contaminants from tailings site
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Characteristics of the Nichromet Technology
Green• Cyanide-free process• Sulfide is recycled as sulfuric
acid • No waste water, no tailing
pond and no air pollutants• Solid wastes : inert and
stable, even when using high arsenic ores
Fast• Leaching time of 2 hours instead of 2 days for cyanide
Flexible• Can handle base metals
(bulk flotation : higher efficiency)
• Can treat carbonaceous ore
• Can handle telluride contamination
Profitable• Process cost ($/oz gold)
similar to cyanide• Capital cost lower (10-15%)
than cyanide
Successfully piloted at the ton scaleon a wide range of materials
Sources TypeGrade (g/T)
Barren Solid (g/T)
Yield (%)
1: Canada (Quebec)
Ore 2,58 g/T 0,07 g/T 97,5 %
2: Canada (Quebec)
Ore 3,45 g/T 0,34 g/T 93,2 %
3: Canada (Quebec)
Ore 13,9 g/T 0,79 g/T 95,4 %
4: Canada (Ontario)*
Conc. 55,3 g/T 4,79 g/T 94,0 %
5 : Eastern Europe*
Conc. 7,5 g/T 1,48 g/T 91,0 %
6: Canada (Quebec)*
Conc. 53,5 g/T 3,56 g/T 94,1 %
*Flotation concentrates requiring pre-treatment by oxidation
Environmental Recognition
Grant of 700 k$ from Green Technologies Demonstration Program of Quebec Government in 2011-2012
Grant of 5 M$ from Sustainable
Technology Development Fund of
Federal Governement in 2013
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Current gold estimated resources (3,2 MT) Gold : 339 000 oz Au @ 3,27 g Au/T Copper : 28 Mlbs @ 0,4 %Cu
Exploitation permit in force
Mining plan Near surface resources (open pit potential, low operating cost)
20 M$ investment done in exploration to date
Somine Haïti Project vs Nichromet Technology
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Phase IBring the top layer of the deposit into production
with a modular plant to process oxides concentrate
15 M$ investment for the modular plant onlyPotential of 25 000 oz Au/year
Phase II1000 TPD Mine and full scale processing plant Gold production rate of 35 000 oz Au/yr Investment for Nichromet processing plant of 35
M$
Nichromet is currently conducting a demonstration program for the application of its technology on the Faille B deposit.
Great Potential for a Nichromet plant in Haïti
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Toward a Greener Gold Industry
