204 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
Uranium Remediation—Case 2
Similar concentration of uranium and vanadium in the
fine fractions were found to occur during HPSA Processing
in another abandoned uranium mine waste test case. The
resulting compositions of three different size fractions mea-
sured via ICP-MS and the associated mass fractions from
dry screening before and after HPSA processing are dis-
played in Figure 9. HPSA processing was found to increase
the –53 µm (–270 US Mesh) size fraction concentration
of uranium by 30% and vanadium by 40%. This second
case provides another example of HPSA concentrating
uranium and vanadium in the fines because of the softer
carnotite fracturing from the harder, larger quartz par-
ticles during processing. Concentrating materials to the
fines allows for on-site separation of radionuclides which
reduces the amount of material that must be transported
offsite, while leaving an inert material for reuse onsite.
Furthermore, because source material is retained in the iso-
lated mineral fraction, post-processing of this material will
be more efficient and produce significantly less waste (Disa
Technologies, Environmental Restoration Group, 2022).
MINERAL PROCESSING APPLICATIONS
Batch Testing Case: Graphite
HPSA optimization tests demonstrated a significant oppor-
tunity for economic improvements when graphite material
was processed in a HPSA batch unit and benchmarked
against the given ball mill process parameters. The same flo-
tation procedure was used to calculate grade and recovery
for the ball mill and HPSA. Figure 10 displays the HPSA
process increased graphite flotation concentrate grade by
approximately 25% at a larger P80, while maintaining simi-
lar recoveries. HPSA has the potential to replace the current
ball mill, multiple downstream regrind mills, by achieving
higher grades further upstream in the circuit, lowering their
utilization to achieve the same final concentrate grade of
95%. Furthermore, HPSA can selectively liberate graph-
ite at a larger flake size unlike the indiscriminate grinding
Figure 8. HPSA processing for AUMs
Figure 9. Uranium and vanadium HPSA processing
Uranium Remediation—Case 2
Similar concentration of uranium and vanadium in the
fine fractions were found to occur during HPSA Processing
in another abandoned uranium mine waste test case. The
resulting compositions of three different size fractions mea-
sured via ICP-MS and the associated mass fractions from
dry screening before and after HPSA processing are dis-
played in Figure 9. HPSA processing was found to increase
the –53 µm (–270 US Mesh) size fraction concentration
of uranium by 30% and vanadium by 40%. This second
case provides another example of HPSA concentrating
uranium and vanadium in the fines because of the softer
carnotite fracturing from the harder, larger quartz par-
ticles during processing. Concentrating materials to the
fines allows for on-site separation of radionuclides which
reduces the amount of material that must be transported
offsite, while leaving an inert material for reuse onsite.
Furthermore, because source material is retained in the iso-
lated mineral fraction, post-processing of this material will
be more efficient and produce significantly less waste (Disa
Technologies, Environmental Restoration Group, 2022).
MINERAL PROCESSING APPLICATIONS
Batch Testing Case: Graphite
HPSA optimization tests demonstrated a significant oppor-
tunity for economic improvements when graphite material
was processed in a HPSA batch unit and benchmarked
against the given ball mill process parameters. The same flo-
tation procedure was used to calculate grade and recovery
for the ball mill and HPSA. Figure 10 displays the HPSA
process increased graphite flotation concentrate grade by
approximately 25% at a larger P80, while maintaining simi-
lar recoveries. HPSA has the potential to replace the current
ball mill, multiple downstream regrind mills, by achieving
higher grades further upstream in the circuit, lowering their
utilization to achieve the same final concentrate grade of
95%. Furthermore, HPSA can selectively liberate graph-
ite at a larger flake size unlike the indiscriminate grinding
Figure 8. HPSA processing for AUMs
Figure 9. Uranium and vanadium HPSA processing