Procemin 2015 Rejection of Pyrite: Challenges and Sustainable Chemical Solutions II

Rejection of pyrite: challenges and
sustainable chemical solutions II

Carmina Quintanar, Cytec Chile Ltda.
Luis Silva, Minera Valle Central.
Current Scenario
The mining industry is currently facing significant
challenges to identify and adopt sustainable processes
that effectively recover value minerals in difficult-to-
process low-grade resources.
These are typically characterized by complex
mineralogy and the presence of significant amounts of
penalty gangue sulfide minerals, especially pyrite which
is a challenge to separate from value minerals at many
major mine operations.
Chilean Mineral Ore Head Grades Evolution,
2004-2014
Consejo Minero. Cochilco Information.

Challenges: Current and Future Trends
Increasing pyrite content (> Fe/Cu ratio)

Increasing the use of sea water (problems
with lime, the typical pyrite depressant)
Negative effect of lime in the recovery of
other valuable elements (Au, Mo)
Handling high quantities of depressant:
logistics and safety issues.
Pyrite in Copper Ores - Facts
Copper concentrate: pyrite content is required
for smelter energy generation (around 15%)
Environment: rejection of pyrite is required
(smelter pollution)
Penalty: commercialization of Copper
concentrates
Mineralogy: liberated or associated to copper
Strategies for rejecting pyrite
Strategy 1: Use of Depressant
Lime
Tannins (Quebracho and other sources)
Sodium Sulfite, Sodium Bisulfite; Sodium Metabisulfite (MBS)
Sodium Cyanide (NaCN)
Other Poly functional Molecules
Strategy 2: Use of a selective collector system

Selective Collectors
Cu versus Fe Recovery
Cu Recovery; %
94 Recovery
DTP IPETC SMTC
92
90
88
86
84
82
80
15 20 25 30 35 40 45 50 55 60
Fe Recovery ; %
Strategy 1:Polymeric Depressant, Aero 7261
Preliminary Laboratory Evaluations
At First Cleaner Stage
Set 1: Different Dosages: 0, 25, 50 and 75 gpt

Set 2 and 3: Comparison with Sodium
Metabisulphite.
Set 4. Open cycle Tests with 4 cleaner stages
First Cleaner Flotation Conditions
First Cleaner Flotation Condition - Denver
Solid 21%
1 900rpm
Conditioning time min
Flotation Time 7 min 1000rpm
AERO7261A Depressant Variable g/t
pH 9,5
Diesel 20 g/t
Frother 1 5 g/t AF-76E
Frother 2 8 g/t MIBC
Water Process
Set 1. Preliminary First Cleaner Test: Different Dosages
Cu and Fe recoveries
Rougher Copper Content (%) Iron Content (%) Molybdenum content (%)
Concentrate
Sample
Pulp 1 3.93 20.67 0.26
Set 1. Preliminary First Cleaner Test: Different Dosages
Fe and Cu First Cleaner conc. grades
Cu conc. grades Fe Conc. Grades

Set 2.Comparison Studies of Aero 7261A with
SMBS
First Cleaner Stage
Rougher Copper Content Iron Content Molybdenum content

Concentrate (%) (%) (%)
Sample
Pulp 2 3.90 29.77 0.187
Pulp 3 6.03 25.06 0.357
SMBS and Aero 7261A Dosages: 55,65,75,85 and 95 gpt

Set 2 and 3. First Cleaner Tests : Aero 7260 vs SMBS
Set 2 and 3. First Cleaner Tests : Aero 7260 vs SMBS
Set 4. Open Cycle Test Conditions
pH Flotation % solid
Time, min
Cleaner Stage 1 9.5 20 33
Cleaner Stage 2 11.5 12 36-42
Cleaner Stage 3 11.5 8 45-51
Cleaner Stage 4 11.5 14 32

Depressant Dosages in OCT
Aero 7261A Cleaner Cleaner Cleaner Cleaner
Depressant Stage 1 Stage 2 Stage 3 Stage 4
Dosage gpt*
Test 1 Control 0 0 0 0
Test 2 50 15 15 15
Test 3 75 0 0 0
Rougher Copper Content Iron Content Molybdenum content

Concentrate (%) (%) (%)
Sample
Pulp 4 2.63 24.15 0.22
Open Cycle Test Results
Test 1Control Test 2 Test 3

Quescam Analysis: Sulfide Components of Pulp 4
Pyrite Liberation
Conclusions
This preliminary studies show a new alternative polymeric
depressants that can be effective to address the increased
levels of pyrite.
These results also demonstrate that it can be more efficient to
use a pyrite depressant like Aero 7261A at cleaning stages
than the use of sodium metabisulphite or lime.
Excess of depressant can affect the Cu and Mo recoveries.
Additional studies have to be done to evaluate the correct
depressant dosage and point of addition to avoid the
depression of valuable species. Cu and Mo depressions were
observed in the second and third cleaner stages mainly at the
OCT.

Procemin 2015 Rejection of Pyrite: Challenges and Sustainable Chemical Solutions II

Uploaded by

Copyright:

Available Formats

Procemin 2015 Rejection of Pyrite: Challenges and Sustainable Chemical Solutions II

Uploaded by

Document Information

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

Procemin 2015 Rejection of Pyrite: Challenges and Sustainable Chemical Solutions II

Uploaded by

Copyright:

Available Formats

Rejection of pyrite: challenges and

sustainable chemical solutions II

Consejo Minero. Cochilco Information.

Increasing pyrite content (> Fe/Cu ratio)

Strategy 2: Use of a selective collector system

Set 1: Different Dosages: 0, 25, 50 and 75 gpt

Flotation Time 7 min 1000rpm

AERO7261A Depressant Variable g/t

Frother 1 5 g/t AF-76E

Frother 2 8 g/t MIBC

Cu conc. grades Fe Conc. Grades

Rougher Copper Content Iron Content Molybdenum content

Pulp 3 6.03 25.06 0.357

SMBS and Aero 7261A Dosages: 55,65,75,85 and 95 gpt

Cleaner Stage 2 11.5 12 36-42

Cleaner Stage 3 11.5 8 45-51

Cleaner Stage 4 11.5 14 32

Rougher Copper Content Iron Content Molybdenum content

Test 1Control Test 2 Test 3

You might also like