4
SPIDER CROWDER EFFECT IN PROCESS
PERFORMANCE
Two different sampling campaigns (before and after the ret-
rofit) were carried out to evaluate the effect of the spider
crowder in process performance. Both campaigns were per-
formed around the upgraded cell, individually, looking for
evaluating the process performance after the installation of
the system. Each sampling campaign was carried out utiliz-
ing two manual samplers: a diaphragm pump sampler and
a lip sampler. Timed sampling was performed with the lip
sampler to be able to collect the concentrate froth directly
from the flotation cell overflow, while the pump was used
to sample the feed and tails of cell 7. The feed from cell 7
was collected from the tails of cell 6.
Four sampling rounds were carried out in each cam-
paign. Accounting for the solids concentration of each con-
centrate sample, the lip length of the lip sampler and cell’s
total lip length, the mass pull is obtained (through timed
sampling with the lip sampler). The feed, concentrate and
tails samples obtained were process at site.
Mass Pull in the upgraded cell obtained from the sam-
pling campaigns were, on average, 13.9 t/h for the first
campaign (before) and 17.8 t/h for the second (after). The
above indicates a 28% mass pull increase, after the installa-
tion of the Spider Crowder system. Also, based on the indi-
cated results, an increase in the Froth Carry Rate (FCR) can
be observed, on average, from 0.49 t/m2h to 0.86 t/m2h,
which results in a 75% improvement after the installation
of the retrofit.
SPIDER CROWDER EFFECT IN THE
OPERATIONAL PARAMETERS
Operational parameters 12-hours average were analyzed,
this included air flowrate and froth depths for studied cell
during the period between January 1st 2023 to June 10th
2023. Trend analysis over time for airflow rate and froth
bed is shown in Figure 6.
Average values for the periods before and after the ret-
rofits are detailed in Table 3. It is noticeable from Figure 6
and Table 3 the change on the operational parameters dur-
ing the evaluation period. Airflow rate decreased by 16%
while froth bed increased by 17%.
CONCLUSIONS
A froth crowding solution named Spider Crowder Upgrade
was developed by Metso to improve froth collection
in a Copper operation with large flotation cells already
equipped with center launders. This is a scale-up advance-
ment from legacy Australian radial crowders. The upgrade
Table 2. Froth Zone parameters before and after Spider
Crowder Upgrade
Cell
TC630
Original
Condition with
Center Launder
Upgraded Condition
with Spider Crowder
FSA (m2) 62.2 41.2
LL (m) 34.6 20.3
Crowding 34.50% 56.60%
Figure 5. Internal view of Spider Crowder Upgrade in cell 7
of Line 1
Figure 6. Time Series Plot for cell 7 in rougher line 1
including air flowrate (Am3/h) and froth dept (mm)
Table 3. Average operational parameters values during
evaluation period
Cell Period
Airflow rate
(m3/h)
Froth bed
(mm)
TC630 Before upgrade 2731 266.3
TC630 After upgrade 2353 311.7
SPIDER CROWDER EFFECT IN PROCESS
PERFORMANCE
Two different sampling campaigns (before and after the ret-
rofit) were carried out to evaluate the effect of the spider
crowder in process performance. Both campaigns were per-
formed around the upgraded cell, individually, looking for
evaluating the process performance after the installation of
the system. Each sampling campaign was carried out utiliz-
ing two manual samplers: a diaphragm pump sampler and
a lip sampler. Timed sampling was performed with the lip
sampler to be able to collect the concentrate froth directly
from the flotation cell overflow, while the pump was used
to sample the feed and tails of cell 7. The feed from cell 7
was collected from the tails of cell 6.
Four sampling rounds were carried out in each cam-
paign. Accounting for the solids concentration of each con-
centrate sample, the lip length of the lip sampler and cell’s
total lip length, the mass pull is obtained (through timed
sampling with the lip sampler). The feed, concentrate and
tails samples obtained were process at site.
Mass Pull in the upgraded cell obtained from the sam-
pling campaigns were, on average, 13.9 t/h for the first
campaign (before) and 17.8 t/h for the second (after). The
above indicates a 28% mass pull increase, after the installa-
tion of the Spider Crowder system. Also, based on the indi-
cated results, an increase in the Froth Carry Rate (FCR) can
be observed, on average, from 0.49 t/m2h to 0.86 t/m2h,
which results in a 75% improvement after the installation
of the retrofit.
SPIDER CROWDER EFFECT IN THE
OPERATIONAL PARAMETERS
Operational parameters 12-hours average were analyzed,
this included air flowrate and froth depths for studied cell
during the period between January 1st 2023 to June 10th
2023. Trend analysis over time for airflow rate and froth
bed is shown in Figure 6.
Average values for the periods before and after the ret-
rofits are detailed in Table 3. It is noticeable from Figure 6
and Table 3 the change on the operational parameters dur-
ing the evaluation period. Airflow rate decreased by 16%
while froth bed increased by 17%.
CONCLUSIONS
A froth crowding solution named Spider Crowder Upgrade
was developed by Metso to improve froth collection
in a Copper operation with large flotation cells already
equipped with center launders. This is a scale-up advance-
ment from legacy Australian radial crowders. The upgrade
Table 2. Froth Zone parameters before and after Spider
Crowder Upgrade
Cell
TC630
Original
Condition with
Center Launder
Upgraded Condition
with Spider Crowder
FSA (m2) 62.2 41.2
LL (m) 34.6 20.3
Crowding 34.50% 56.60%
Figure 5. Internal view of Spider Crowder Upgrade in cell 7
of Line 1
Figure 6. Time Series Plot for cell 7 in rougher line 1
including air flowrate (Am3/h) and froth dept (mm)
Table 3. Average operational parameters values during
evaluation period
Cell Period
Airflow rate
(m3/h)
Froth bed
(mm)
TC630 Before upgrade 2731 266.3
TC630 After upgrade 2353 311.7