996 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
operations are challenging and complex in nature, therefore
creating logic to mitigate risks relieved pressure from the
operations team.
Pueblo Viejo and Woodgrove worked closely together
throughout the integration process via video calls and digi-
tal messaging platforms to maintain constant and seamless
communications. The dedication to the success of the proj-
ect was evident as both sides ensured communication was
constant and all concerns were highlighted and brought to
the attention of the proper personnel in a timely manner.
Due to the effective communication between both parties,
no lag time was experienced during the integration and
tuning of the system, resulting in a successful integration of
a world-class autoclave APC system despite the restrictions
and confines of working within the COVID-19 pandemic
public safety measures.
RESULTS AND DISCUSSION
Improved stability was observed at the start of the tuning
phase of the project. Disturbances that would usually cause
instability were quickly controlled by the AwaRE ® APC
system by making adjustments to the Feed Flow, Oxygen
injection, and HPCW injection controllers. The section
below outlines the performance improvements realized by
the Pueblo Viejo operations team in the months follow-
ing the successful deployment of the AwaRE ® system. The
result of improved control is evident in all the main process
parameters for each of the four autoclaves, namely AC150,
AC250, AC350, and AC450. All figures show the relevant
process parameter with its unit in bins on the x-axis and the
percentage of time the process parameter was in that bin
on the y-axis. For this analysis it was ensured that an equal
number of datapoints were used for the AwaRE ® ON and
AwaRE ® OFF time periods, with ~1.5 months of data used
for each period for a total of three months of data.
Figure 5 to Figure 10 shows the improved performance
and stability added by the APC system for autoclave AC150.
The APC system integrated in autoclave AC150 was able
to increase the average Feed Flow by 3.6% and decreased
the average Vent Valve Position by 38%. The reduction in
the average vent valve position signifies the effective perfor-
mance of the AwaRE ® APC system in optimizing oxygen
addition to the autoclave without over-supplying. This is
particularly critical at Pueblo Viejo, not only for enhancing
autoclave efficiency but also to guarantee a consistent and
sufficient oxygen supply for all four autoclaves ensuring
none of the autoclaves are being starved of oxygen.
The APC control proved effective in stabilizing key
measured variables even with increased throughput, as dem-
onstrated by the reduced Standard Deviation (SD) for each
main measured variable. Notably, the Vent Valve Position
exhibited a 57% decrease in SD, indicating enhanced reg-
ulation of oxygen addition within the autoclave. A 38%
decrease in the SD of Vent Temperature signifies improved
stability, crucial for maintaining desired process condi-
tions. Autoclave Pressure and Autoclave Level saw reduc-
tions of 54% and 9.4% in SD, respectively, which ensures
consistent operations within the autoclave. Additionally,
the SD of Autoclave Oxidation Efficiency decreased by
22%, showcasing the benefit of optimizing chemical reac-
tions within the autoclave and enhancing overall process
efficiency. Table 1 to Table 4 shows the average, SD, and
percentage difference between the OFF and ON time peri-
ods for all main parameters for autoclaves AC150, AC250,
AC350, and AC450 respectively. Similar results achieved
for AC150 were observed for the three other autoclaves
Figure 5. AC150 Feed flow distribution for AwaRE® OFF (left) and ON (right)
operations are challenging and complex in nature, therefore
creating logic to mitigate risks relieved pressure from the
operations team.
Pueblo Viejo and Woodgrove worked closely together
throughout the integration process via video calls and digi-
tal messaging platforms to maintain constant and seamless
communications. The dedication to the success of the proj-
ect was evident as both sides ensured communication was
constant and all concerns were highlighted and brought to
the attention of the proper personnel in a timely manner.
Due to the effective communication between both parties,
no lag time was experienced during the integration and
tuning of the system, resulting in a successful integration of
a world-class autoclave APC system despite the restrictions
and confines of working within the COVID-19 pandemic
public safety measures.
RESULTS AND DISCUSSION
Improved stability was observed at the start of the tuning
phase of the project. Disturbances that would usually cause
instability were quickly controlled by the AwaRE ® APC
system by making adjustments to the Feed Flow, Oxygen
injection, and HPCW injection controllers. The section
below outlines the performance improvements realized by
the Pueblo Viejo operations team in the months follow-
ing the successful deployment of the AwaRE ® system. The
result of improved control is evident in all the main process
parameters for each of the four autoclaves, namely AC150,
AC250, AC350, and AC450. All figures show the relevant
process parameter with its unit in bins on the x-axis and the
percentage of time the process parameter was in that bin
on the y-axis. For this analysis it was ensured that an equal
number of datapoints were used for the AwaRE ® ON and
AwaRE ® OFF time periods, with ~1.5 months of data used
for each period for a total of three months of data.
Figure 5 to Figure 10 shows the improved performance
and stability added by the APC system for autoclave AC150.
The APC system integrated in autoclave AC150 was able
to increase the average Feed Flow by 3.6% and decreased
the average Vent Valve Position by 38%. The reduction in
the average vent valve position signifies the effective perfor-
mance of the AwaRE ® APC system in optimizing oxygen
addition to the autoclave without over-supplying. This is
particularly critical at Pueblo Viejo, not only for enhancing
autoclave efficiency but also to guarantee a consistent and
sufficient oxygen supply for all four autoclaves ensuring
none of the autoclaves are being starved of oxygen.
The APC control proved effective in stabilizing key
measured variables even with increased throughput, as dem-
onstrated by the reduced Standard Deviation (SD) for each
main measured variable. Notably, the Vent Valve Position
exhibited a 57% decrease in SD, indicating enhanced reg-
ulation of oxygen addition within the autoclave. A 38%
decrease in the SD of Vent Temperature signifies improved
stability, crucial for maintaining desired process condi-
tions. Autoclave Pressure and Autoclave Level saw reduc-
tions of 54% and 9.4% in SD, respectively, which ensures
consistent operations within the autoclave. Additionally,
the SD of Autoclave Oxidation Efficiency decreased by
22%, showcasing the benefit of optimizing chemical reac-
tions within the autoclave and enhancing overall process
efficiency. Table 1 to Table 4 shows the average, SD, and
percentage difference between the OFF and ON time peri-
ods for all main parameters for autoclaves AC150, AC250,
AC350, and AC450 respectively. Similar results achieved
for AC150 were observed for the three other autoclaves
Figure 5. AC150 Feed flow distribution for AwaRE® OFF (left) and ON (right)