266 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
Breakage and Selectivity
The ability to break particles was initially tested with single-
particle, single-discharge tests placed between the two-bar
electrode-grizzly set-up at different HVP settings. High-
speed camera footage was taken to observe the phenomena,
as shown in an example in Figure 7. The images show an
arc formation, illustrated by a bright spark, followed by the
disintegration of the particle.
Tests were conducted to evaluate the selectivity of
breakage using pairs of synthetic particles consisting of
one high-grade particle and one barren particle. The high-
grade particles were composed of construction grout with
a segment of copper wire embedded in the middle, while
the barren particles were made solely of grout. Both types
of particles were cylindrical with a diameter and height of
20 mm.
Breakage selectivity was determined based on which
particle experienced damage after being subjected to a sin-
gle discharge. The gap between the electrode bars was set at
20 mm. Figure 8 shows a fragmented high-grade particle
resulting from one of the batch tests next to an unbroken
barren particle.
High-grade synthetic particles were selectively targeted
over 90% of the time in the conducted tests. Similarly,
paired tests involving real ore particles were carried out,
where high-grade particles were represented by mineralized
Cu/Au particles, and barren ore was represented by basalt
particles. Basalt was chosen to represent barren particles
due to its minimal content of conductive material and high
homogeneity. In this scenario, the tests showed a slightly
lower selectivity than synthetic particle tests, averaging
82% selectivity. The reduced selectivity observed could be
attributed to the varying grades of the mineralized particles
or particle shapes, which could affect how they sit on the
Figure 7. High-speed camera image of transfer of High Voltage Pulse through an ore particle showing breakage
Figure 8. Synthetic particles pair after tests to evaluate the
selectivity of breakage
Breakage and Selectivity
The ability to break particles was initially tested with single-
particle, single-discharge tests placed between the two-bar
electrode-grizzly set-up at different HVP settings. High-
speed camera footage was taken to observe the phenomena,
as shown in an example in Figure 7. The images show an
arc formation, illustrated by a bright spark, followed by the
disintegration of the particle.
Tests were conducted to evaluate the selectivity of
breakage using pairs of synthetic particles consisting of
one high-grade particle and one barren particle. The high-
grade particles were composed of construction grout with
a segment of copper wire embedded in the middle, while
the barren particles were made solely of grout. Both types
of particles were cylindrical with a diameter and height of
20 mm.
Breakage selectivity was determined based on which
particle experienced damage after being subjected to a sin-
gle discharge. The gap between the electrode bars was set at
20 mm. Figure 8 shows a fragmented high-grade particle
resulting from one of the batch tests next to an unbroken
barren particle.
High-grade synthetic particles were selectively targeted
over 90% of the time in the conducted tests. Similarly,
paired tests involving real ore particles were carried out,
where high-grade particles were represented by mineralized
Cu/Au particles, and barren ore was represented by basalt
particles. Basalt was chosen to represent barren particles
due to its minimal content of conductive material and high
homogeneity. In this scenario, the tests showed a slightly
lower selectivity than synthetic particle tests, averaging
82% selectivity. The reduced selectivity observed could be
attributed to the varying grades of the mineralized particles
or particle shapes, which could affect how they sit on the
Figure 7. High-speed camera image of transfer of High Voltage Pulse through an ore particle showing breakage
Figure 8. Synthetic particles pair after tests to evaluate the
selectivity of breakage