2341
Achieving Operational Excellence by Leveraging Flotation
Chemistry and Mineralogy
Mark Carlisle, Catherine Dunn, Ronel Kappes
Newmont Corporation
ABSTRACT: Understanding flotation chemistry and the impact that mineralogy has on flotation chemistry
is critical to improve and optimize flotation performance beyond that achieved by the physical (cell and circuit
design) and operational (particle size, %solids, control) components. Flotation chemistry is often undervalued
due to the complexity of interacting variables and the difficulty of scaling laboratory testing to operating
performance. A recent operational example of floating complex polymetallic ores in the presence of organic
carbon will be used to demonstrate the value of understanding both mineralogy and flotation chemistry in
achieving significant operational improvements.
INTRODUCTION
Mineralogy plays a key role in most mineral processing
design considerations and particularly for physical separa-
tions such as flotation. Not only are the associations and
liberation of the valuable minerals of importance, but the
deportment of gangue minerals can become a critical vari-
able to the overall success of the intended separation. Gangue
minerals, or minerals that provide no economic value to the
process, occur in two broad categories. The first category
are sulfide minerals with minerals such as pyrite and pyr-
rhotite being the most prevalent. Depending on the desired
separation, there may be a whole host of other sulfide min-
erals that either don’t add economic value to the process, or
result in higher operating costs (examples include bismuth,
antimony, mercury etc.). The second major gangue mineral
category is non-sulfide gangue (NSG). NSG can be further
subdivided into silica-bearing minerals such as quartz and a
host of other silicates (talc, sericite, kaolinite) and carbon-
bearing minerals such as organic carbon and a variety of
carbonate minerals (Orlich et al., 2009).
The presence of organic carbon is not an uncommon
concern in the flotation of complex polymetallic ores.
Dealing with carbonaceous gold-robbing ores has also been
a challenging topic in the gold industry for a long time,
with a number of approaches applied in industry in order
to mitigate the impact on overall gold recovery. The key
physical separation processes applied in industry (La Brooy
et al., 2017), include:
• Gravity
• Carbon pre-flotation
• Cyclone separation (discarding the overflow)
By far the most widely applied physical separation approach,
considers the application of a carbon pre-flotation circuit,
typically with very little consideration of a targeted flotation
chemistry, other than addition of a frother. The application
of carbon pre-flotation is often challenged, likely due to:
• Slow floating nature of organic carbon.
• The activity of the organic carbon—results in signifi-
cant absorption of reagents (frother, collector etc.).
Achieving Operational Excellence by Leveraging Flotation
Chemistry and Mineralogy
Mark Carlisle, Catherine Dunn, Ronel Kappes
Newmont Corporation
ABSTRACT: Understanding flotation chemistry and the impact that mineralogy has on flotation chemistry
is critical to improve and optimize flotation performance beyond that achieved by the physical (cell and circuit
design) and operational (particle size, %solids, control) components. Flotation chemistry is often undervalued
due to the complexity of interacting variables and the difficulty of scaling laboratory testing to operating
performance. A recent operational example of floating complex polymetallic ores in the presence of organic
carbon will be used to demonstrate the value of understanding both mineralogy and flotation chemistry in
achieving significant operational improvements.
INTRODUCTION
Mineralogy plays a key role in most mineral processing
design considerations and particularly for physical separa-
tions such as flotation. Not only are the associations and
liberation of the valuable minerals of importance, but the
deportment of gangue minerals can become a critical vari-
able to the overall success of the intended separation. Gangue
minerals, or minerals that provide no economic value to the
process, occur in two broad categories. The first category
are sulfide minerals with minerals such as pyrite and pyr-
rhotite being the most prevalent. Depending on the desired
separation, there may be a whole host of other sulfide min-
erals that either don’t add economic value to the process, or
result in higher operating costs (examples include bismuth,
antimony, mercury etc.). The second major gangue mineral
category is non-sulfide gangue (NSG). NSG can be further
subdivided into silica-bearing minerals such as quartz and a
host of other silicates (talc, sericite, kaolinite) and carbon-
bearing minerals such as organic carbon and a variety of
carbonate minerals (Orlich et al., 2009).
The presence of organic carbon is not an uncommon
concern in the flotation of complex polymetallic ores.
Dealing with carbonaceous gold-robbing ores has also been
a challenging topic in the gold industry for a long time,
with a number of approaches applied in industry in order
to mitigate the impact on overall gold recovery. The key
physical separation processes applied in industry (La Brooy
et al., 2017), include:
• Gravity
• Carbon pre-flotation
• Cyclone separation (discarding the overflow)
By far the most widely applied physical separation approach,
considers the application of a carbon pre-flotation circuit,
typically with very little consideration of a targeted flotation
chemistry, other than addition of a frother. The application
of carbon pre-flotation is often challenged, likely due to:
• Slow floating nature of organic carbon.
• The activity of the organic carbon—results in signifi-
cant absorption of reagents (frother, collector etc.).