XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 1499
prepared sample, screened to meet their criteria and free
of fine material that would bypass the sorter. In addition,
a larger sample mass is requested to allow the pilot plant
unit to run at a reasonable feedrate for an adequate period
of time.
These performance tests provide estimates on how an
optimized sorter would operate but offer limited informa-
tion to the company/project owner of their material char-
acteristics and overarching economic considerations. In
addition, collecting such a large sample mass requires com-
positing core intervals from a wide area of the deposit or
whatever material is accessible from adits, declines or close
to the surface. This one sample is not representative of the
deposit and certainly does not reflect what would be sent
to a pre-concentration circuit. In particular, there are no
details on the bypass fraction as these particles are too fine
to send to a sensor based particle sorting unit.
Mineralogical Testing
At the other end of the scale, electron microscopy (e.g.,
QEMSCAN) can be used to infer pre-concentration poten-
tial (SRC, 2023). While this suits the type of samples avail-
able in early-stage studies (i.e., half core intervals), this does
not provide any insight into how the material would frag-
ment and present itself after being crushed ahead of a par-
ticle sorter. Limitations on particle size and scanning area
also restrict the robustness of QEMSCAN analysis.
Gaps in Current Testing
With an increasing number of mining companies investi-
gating the potential for pre-concentration on their projects,
there is a need for a standardized protocol, with all test-
ing completed by a fully independent laboratory. This is
how all other types of metallurgical testwork are currently
conducted.
Source: SRC 2023
Figure 3. Different stages of sensor-based testing over project life
prepared sample, screened to meet their criteria and free
of fine material that would bypass the sorter. In addition,
a larger sample mass is requested to allow the pilot plant
unit to run at a reasonable feedrate for an adequate period
of time.
These performance tests provide estimates on how an
optimized sorter would operate but offer limited informa-
tion to the company/project owner of their material char-
acteristics and overarching economic considerations. In
addition, collecting such a large sample mass requires com-
positing core intervals from a wide area of the deposit or
whatever material is accessible from adits, declines or close
to the surface. This one sample is not representative of the
deposit and certainly does not reflect what would be sent
to a pre-concentration circuit. In particular, there are no
details on the bypass fraction as these particles are too fine
to send to a sensor based particle sorting unit.
Mineralogical Testing
At the other end of the scale, electron microscopy (e.g.,
QEMSCAN) can be used to infer pre-concentration poten-
tial (SRC, 2023). While this suits the type of samples avail-
able in early-stage studies (i.e., half core intervals), this does
not provide any insight into how the material would frag-
ment and present itself after being crushed ahead of a par-
ticle sorter. Limitations on particle size and scanning area
also restrict the robustness of QEMSCAN analysis.
Gaps in Current Testing
With an increasing number of mining companies investi-
gating the potential for pre-concentration on their projects,
there is a need for a standardized protocol, with all test-
ing completed by a fully independent laboratory. This is
how all other types of metallurgical testwork are currently
conducted.
Source: SRC 2023
Figure 3. Different stages of sensor-based testing over project life