XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 199
the particles collide, distort, deform, and either rebound
or fracture. During the distortion and rebound, grains of
the processed particles with contrasting mineral proper-
ties can distort and fracture disproportionately, resulting
in more selective liberation of processed materials, making
HPSA technology distinct from other millimeter scale min-
eral processing technologies. HPSA’s selective mineral lib-
eration can potentially reduce downstream processing costs
by selectively liberating desirable minerals and separating
them from downstream minerals that have high processing/
removal costs.
Mineral Processing Requirements
The current target particle size range for HPSA technology
is a feed 100% passing (F100) of 6.35 millimeters to 100
microns. However, future units may have the capacity to
process top sizes of 25 millimeters and larger. The relation-
ship of comminution energy vs particle size is well known
where energy input significantly increases as particle size
decreases (Valery, 2016). In traditional grinding and HPSA
liberation, larger particles create more breakage events due
to more energy transferred during collisions. Furthermore,
HPSA technology can be applied to any circuit with min-
erals exhibiting bi-modal hardness. Simple Mohs Hardness
comparison analysis of minerals can be used to evaluate the
likelihood of fracture. Minerals with larger differences in
hardness will facilitate intergranular fracture and detach-
ment during the particle-particle interactions. However,
HPSA does not work well if the target mineral is a soft
ore inclusion inside of a hard host material as illustrated
in Figure 2. Testing on high inclusion material feedstock
has shown conventional milling is generally more efficient
than the HPSA process. Successful applications currently
include but are not limited to uranium, vanadium, phos-
phate, potash, graphite, copper, molybdenum, gold, rare
earth elements, and filter sand. Furthermore, studies have
been conducted at Montana Technological University
(Harvey, 2023). HPSA testing at Disa has focused process
development for feedstocks with diameters 6.35 mm and
below however, HPSA has been tested with up to 9 mm
particles, see Table 1.
HPSA System Development
Industrial and government collaborations with Disa have
fueled the continuous improvement design process for
HPSA prototype units for batch units for lab studies and
industrial scale units for operation. Table 2 lists details
about the current batch and industrial units used for the
remedial and mineral processing applications detailed in
this paper.
The technology has grown from batch units for lab
testing, to continuous prototypes to validate future large-
scale systems.
Batch Test Unit Evolution— Disa currently uses HPSA
laboratory batch units for material amenability testing and
process optimization. The batch units are used in a con-
trolled testing environment to quantify HPSA’s mineral
liberation, grade, recovery, and specific energy potential
to benchmark against current milling/processing opera-
tions. Test systems have various sample ports, sensors,
and configurations used to assess process and design per-
formance throughout testing. The batch unit design has
undergone multiple improvements to become more modu-
lar and adaptable for testing campaigns. Improvements
have included nozzle optimization (velocity, angle, and
distance), collision chamber design, and slurry fluid flow
design. Additional modifications led to the design of a next
generation prototype and a bench scale unit to facilitate a
smaller unit footprint and smaller sample volumes required
for testing. Figure 3 displays the evolution of the HPSA
batch unit design, from the original patent to the current
units.
Continuous Unit Evolution— The first continuous
HPSA unit, Generation Alpha (Gen A), was piloted in
2018 at an iron mine, displayed in Figure 4. The lessons
learned from Gen A were used to design Generation Bravo
(Gen B) in 2022 and deploy it in the field in 2023, Figure 5.
Process design improvements included the addition of agi-
tation, increased unit throughput, the design of an easily
transportable HPSA skid, mitigation of equipment wear,
and the addition of process monitoring and controls.
Gen B was initially designed to process Abandoned
Uranium Mines (AUMs) waste piles however, the unit has
now been applied to multiple additional mineral processing
Table 1. Mineral feedstock targets
Units Low Target High
Input Feed Particle Size (F100) mm (in) -6.35 (0.25) 9 (0.35”)
Difference in Moh’s Hardness -1 --
Material Feedstocks tested: uranium, vanadium, phosphate, potash, graphite, copper, molybdenum, gold, rare earth
elements, and filtration filter sand,
the particles collide, distort, deform, and either rebound
or fracture. During the distortion and rebound, grains of
the processed particles with contrasting mineral proper-
ties can distort and fracture disproportionately, resulting
in more selective liberation of processed materials, making
HPSA technology distinct from other millimeter scale min-
eral processing technologies. HPSA’s selective mineral lib-
eration can potentially reduce downstream processing costs
by selectively liberating desirable minerals and separating
them from downstream minerals that have high processing/
removal costs.
Mineral Processing Requirements
The current target particle size range for HPSA technology
is a feed 100% passing (F100) of 6.35 millimeters to 100
microns. However, future units may have the capacity to
process top sizes of 25 millimeters and larger. The relation-
ship of comminution energy vs particle size is well known
where energy input significantly increases as particle size
decreases (Valery, 2016). In traditional grinding and HPSA
liberation, larger particles create more breakage events due
to more energy transferred during collisions. Furthermore,
HPSA technology can be applied to any circuit with min-
erals exhibiting bi-modal hardness. Simple Mohs Hardness
comparison analysis of minerals can be used to evaluate the
likelihood of fracture. Minerals with larger differences in
hardness will facilitate intergranular fracture and detach-
ment during the particle-particle interactions. However,
HPSA does not work well if the target mineral is a soft
ore inclusion inside of a hard host material as illustrated
in Figure 2. Testing on high inclusion material feedstock
has shown conventional milling is generally more efficient
than the HPSA process. Successful applications currently
include but are not limited to uranium, vanadium, phos-
phate, potash, graphite, copper, molybdenum, gold, rare
earth elements, and filter sand. Furthermore, studies have
been conducted at Montana Technological University
(Harvey, 2023). HPSA testing at Disa has focused process
development for feedstocks with diameters 6.35 mm and
below however, HPSA has been tested with up to 9 mm
particles, see Table 1.
HPSA System Development
Industrial and government collaborations with Disa have
fueled the continuous improvement design process for
HPSA prototype units for batch units for lab studies and
industrial scale units for operation. Table 2 lists details
about the current batch and industrial units used for the
remedial and mineral processing applications detailed in
this paper.
The technology has grown from batch units for lab
testing, to continuous prototypes to validate future large-
scale systems.
Batch Test Unit Evolution— Disa currently uses HPSA
laboratory batch units for material amenability testing and
process optimization. The batch units are used in a con-
trolled testing environment to quantify HPSA’s mineral
liberation, grade, recovery, and specific energy potential
to benchmark against current milling/processing opera-
tions. Test systems have various sample ports, sensors,
and configurations used to assess process and design per-
formance throughout testing. The batch unit design has
undergone multiple improvements to become more modu-
lar and adaptable for testing campaigns. Improvements
have included nozzle optimization (velocity, angle, and
distance), collision chamber design, and slurry fluid flow
design. Additional modifications led to the design of a next
generation prototype and a bench scale unit to facilitate a
smaller unit footprint and smaller sample volumes required
for testing. Figure 3 displays the evolution of the HPSA
batch unit design, from the original patent to the current
units.
Continuous Unit Evolution— The first continuous
HPSA unit, Generation Alpha (Gen A), was piloted in
2018 at an iron mine, displayed in Figure 4. The lessons
learned from Gen A were used to design Generation Bravo
(Gen B) in 2022 and deploy it in the field in 2023, Figure 5.
Process design improvements included the addition of agi-
tation, increased unit throughput, the design of an easily
transportable HPSA skid, mitigation of equipment wear,
and the addition of process monitoring and controls.
Gen B was initially designed to process Abandoned
Uranium Mines (AUMs) waste piles however, the unit has
now been applied to multiple additional mineral processing
Table 1. Mineral feedstock targets
Units Low Target High
Input Feed Particle Size (F100) mm (in) -6.35 (0.25) 9 (0.35”)
Difference in Moh’s Hardness -1 --
Material Feedstocks tested: uranium, vanadium, phosphate, potash, graphite, copper, molybdenum, gold, rare earth
elements, and filtration filter sand,