10
Solution—Quality Assurance And Control
Routine inspections of the spent media bunker should be
carried out to assess the wear on the media. Misshapen,
spalled, or broken media is a sign that the media is of poor
quality or the operating conditions inside the mill are not
favorable such as a low rock load or operating at too high
of a mill speed.
Quality grinding media is critical to maintain stable
SAG mill operation. There are often constraints on grinding
media such as availability and cost, and to reduce operating
costs operations will choose lower quality media from a less
reputable vendor. Lower cost media can have some inher-
ent risks like poor quality control in terms of composition
and hardness profiles. Routine third party QA/QC testing
should be conducted to confirm grinding media meets the
operations required specifications. The information can
also be used to optimize the media design to reduce wear
and breakage.
CONCLUSIONS
In conclusion, this technical paper has provided a compre-
hensive exploration of the common challenges and opti-
mization strategies for increasing the stability of the SAG
mill load. The SAG mill, as the central component of the
milling circuit, is often the primary bottleneck for through-
put and faces numerous operational challenges that can
hinder its load stability and limiting performance. These
challenges include feed variability, grinding media and liner
wear, instrumentation and control, and liner design. The
paper has shed light on the root causes of these challenges
and offered practical solutions to enhance SAG mill stabil-
ity to improve throughput, grind size, and liner life.
The paper emphasizes the importance of understand-
ing and managing factors such as ore variability, primary
crusher control, and the operation of recycle pebble
crushers. Achieving SAG mill load stability through care-
ful management of control parameters, proper liner wear
monitoring, and optimizing liner designs is vital. The role
of instrumentation and control systems in maintaining
optimal SAG mill operations is also highlighted. Accurate
flow meters, microphones, and vibration sensors are essen-
tial tools that should not be overlooked. The implementa-
tion of these strategies and insights can lead to significant
improvements in SAG mill performance.
In summary, this paper serves as a valuable resource
for mill operators and professionals in the mining indus-
try, offering a detailed overview of the challenges faced in
SAG mill operations and providing a roadmap for opti-
mizing SAG mill performance. By addressing the issues
and implementing the recommended strategies, operators
can enhance the stability, efficiency, and longevity of SAG
mills, ultimately improving the overall milling circuit’s pro-
ductivity and profitability.
ACKNOWLEDGMENTS
I would like to acknowledge my co-authors for their time
and effort contributing to this paper.
Data from this manuscript had been presented at the
MINEXCHANGE 2024 SME Annual Conference &
Expo, February 25–28, 2024, held in Phoenix, Arizona.
Figure 14. Deformed grinding media
Figure 15. Deformed grinding media blinding SAG mill
discharge grates
Solution—Quality Assurance And Control
Routine inspections of the spent media bunker should be
carried out to assess the wear on the media. Misshapen,
spalled, or broken media is a sign that the media is of poor
quality or the operating conditions inside the mill are not
favorable such as a low rock load or operating at too high
of a mill speed.
Quality grinding media is critical to maintain stable
SAG mill operation. There are often constraints on grinding
media such as availability and cost, and to reduce operating
costs operations will choose lower quality media from a less
reputable vendor. Lower cost media can have some inher-
ent risks like poor quality control in terms of composition
and hardness profiles. Routine third party QA/QC testing
should be conducted to confirm grinding media meets the
operations required specifications. The information can
also be used to optimize the media design to reduce wear
and breakage.
CONCLUSIONS
In conclusion, this technical paper has provided a compre-
hensive exploration of the common challenges and opti-
mization strategies for increasing the stability of the SAG
mill load. The SAG mill, as the central component of the
milling circuit, is often the primary bottleneck for through-
put and faces numerous operational challenges that can
hinder its load stability and limiting performance. These
challenges include feed variability, grinding media and liner
wear, instrumentation and control, and liner design. The
paper has shed light on the root causes of these challenges
and offered practical solutions to enhance SAG mill stabil-
ity to improve throughput, grind size, and liner life.
The paper emphasizes the importance of understand-
ing and managing factors such as ore variability, primary
crusher control, and the operation of recycle pebble
crushers. Achieving SAG mill load stability through care-
ful management of control parameters, proper liner wear
monitoring, and optimizing liner designs is vital. The role
of instrumentation and control systems in maintaining
optimal SAG mill operations is also highlighted. Accurate
flow meters, microphones, and vibration sensors are essen-
tial tools that should not be overlooked. The implementa-
tion of these strategies and insights can lead to significant
improvements in SAG mill performance.
In summary, this paper serves as a valuable resource
for mill operators and professionals in the mining indus-
try, offering a detailed overview of the challenges faced in
SAG mill operations and providing a roadmap for opti-
mizing SAG mill performance. By addressing the issues
and implementing the recommended strategies, operators
can enhance the stability, efficiency, and longevity of SAG
mills, ultimately improving the overall milling circuit’s pro-
ductivity and profitability.
ACKNOWLEDGMENTS
I would like to acknowledge my co-authors for their time
and effort contributing to this paper.
Data from this manuscript had been presented at the
MINEXCHANGE 2024 SME Annual Conference &
Expo, February 25–28, 2024, held in Phoenix, Arizona.
Figure 14. Deformed grinding media
Figure 15. Deformed grinding media blinding SAG mill
discharge grates