Imagine the result
The SART process: an attractive technology to recover
copper and cyanide from gold mining
Humberto Estay Cuenca, Pablo Carvajal Febre and
Francisco Arriagada House
Arcadis Chile
2 © 2009 ARCADIS 23 April 2012
Contents
1. Introduction
2. The SART process
• Description of the SART process
• SART process integration in cyanidation
circuit
3. Main aspects of design and safety of the SART
process
4. Case of study
5. Overview of the current SART plants in the world
6. Conclusions
3 © 2009 ARCADIS 23 April 2012
1. Introduction
Copper
content in
Gold Ore
Presence of
Cyanide
Soluble Copper
• In some cases, contaminating
dore metal
• Increases the cyanide
consumption
• Gradual increment in the
concentration of copper in
solution circuit
• Reducing Au adsorption in
carbon stage
• Increasing elusion cycle
Increases the operational cost and reduces the incomes,
reducing the mine resources and profitability of the project
4 © 2009 ARCADIS 23 April 2012
1. Introduction
ARCADIS CHILE has conducted the design of SART plant for Maricunga (750 m3/h), the
second largest SART plant in the world, among others studies (design and pilot plants
operations)
Cu-CN
(aq) SART Process
Cu2S
CN-
The SART Process (Sulphidization, Acidification, Recycling and Thickening) is a new
technology developed by Lakefield Research in Canada (MacPhail, P., Fleming, C., Sarbutt, K.
1998)
5 © 2009 ARCADIS 23 April 2012
2. The SART process - description
NaSH Solution
H2SO4
SART Reactor
Lime
Cu2S
NaOH
Treated Solution
CN-
Gypsum
Wash Water
Wash Water
Precipitate THK
Gypsum THK
Neut Reactor
Pp Filter
Gypsum Filter
Flocculant
Flocculant
2
442 )(22 SOacHCNSOHCN
)(6)(6)(2 2
22
3 acHCNsSCuHSCNCu
SART Rx, pH 4-5
OHCNCaOHCaacHCN 222 2)()()(2
Neut Rx, pH 11
Treated Air
NaOH
Scrubber
6 © 2009 ARCADIS 23 April 2012
2. The SART process - integration
HEAP LEACH
ADR/EW PLS Pond
Barren Solution
Barren Pond
NaCN
SART
NaSH, H2SO4
Ca(OH)2
Cu2S
Gypsum
Dore
Metal
7 © 2009 ARCADIS 23 April 2012
3. Main aspects of design and safety of the SART process
• Copper recovery and reagents consumptions Laboratory tests
• Defining plant capacity Q(SART)=f([Cu]eq)
• Design of solid-liquid separation operations Pilot plant tests
• Design focused to personnel safety Extraction system,
sealed equipments and
gas sensors
8 © 2009 ARCADIS 23 April 2012
4. Case of study
HEAP LEACH
ADR/EW PLS Pond
Barren Solution
Barren Pond
NaCN
SART
NaSH, H2SO4
Ca(OH)2
Cu2S
Gypsum
Dore
Metal
Operational Data:
• HL treatment: 20,000 t/day
• Gold grade: 0.8 g/t
• Gold recovery: 60%
• Copper CN-sol grade: 600 g/t
• Copper dissolution: 65%
• NaCN base consumption: 0.15
kg/t (not include CN cons. by Cu)
• Life of mine: 10 years
• SART Recovery: 90%
9 © 2009 ARCADIS 23 April 2012
4. Case of study
Metallurgical Impact
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
0 20 40 60 80 100
[Cu
], m
g/l
PLS Fraction Treated in SART Plant, %
[Cu] Concentration in ADR Plant
0
1.000
2.000
3.000
4.000
5.000
6.000
7.000
0 15 30 50 65 90 100
Mas
s, t
on
/ye
ar
PLS Fraction Treated in SART Plant, %
Copper Production and NaCN Recovered
Cu Prod
NaCN Rec
10 © 2009 ARCADIS 23 April 2012
4. Case of study
0
50.000
100.000
150.000
200.000
250.000
300.000
350.000
No Cu 0% SART 15% SART
30% SART
50% SART
65% SART
90% SART
100% SART
NP
V, k
US$
Cases
Impact of SART Plant in NPVEconomic Impact
• Gold Price: 1,200 US$/Oz
• Copper Price: 2.4 US$/lb
• NaCN Cost: 2,200 US$/ton
• Base Op. Cost: 5.0 US$/ton
(not include NaCN cost)
• SART Op. Cost: 0.8 US$/m3
• Invest. Cost: 500 MUS$
• SART Invest. Cost: 60,000
US$/(m3/h)
• Discount Rate: 5%
11 © 2009 ARCADIS 23 April 2012
4. Case of study Economic Impact (Assuming increasing mining resources)
0
100.000
200.000
300.000
400.000
500.000
600.000
No Cu 0% SART 50% SART 10 years
50% SART 12 years
50% SART 15 years
NP
V, k
US$
Cases
Impact of SART Plant in NPV
SART Process could increase the mine resources and NPV of the project
12 © 2009 ARCADIS 23 April 2012
5. Overview of Current SART Plants in the World
Plant Telfer Yanacocha Lluvia de
Oro Gedabek Mastra
Maricunga
(under
construct.)
Country Australia Peru Mexico Azerbaijan Turkey Chile
Capacity, m3/h 40 1,200 340 140 120 750
Flow Treated PLS PLS - PLS - PLS
[Cu], mg/l 1,000 1,000 - 800 1,500 450
Cu Rec, % 90 70 95 95 99 80
Cu Prod, t/d 0.9 20 1.0 2.5 4.0 6.5
Year Op. 2006 2008 2008 2009 2010 2012
13 © 2009 ARCADIS 23 April 2012
6. Conclusions
• The SART process is a strong option to treat cyanide solutions with copper
contents, recovering copper and cyanide from the process.
• The correct design of a SART plant must include laboratory and pilot plant test
works, in order to define the main equipments. Additionally, design must be
focused on ensuring the safety of the personnel.
• The case of study demonstrates that SART process increases the profitability
of a cyanidation plant with copper contents and make possible the treatment
of gold ores with high soluble copper contents, even increasing the mine
resources.
• Five SART plants are currently operating in the world, and one under
construction, showing the high interest and feasibility of this technology.