2892 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
of pyrite particles. Tests were performed on the 6-litre lab-
scale version of FLSmidth’s nextSTEP ™ rotor-stator in a
cylindrical tank. Four concentrates were collected at cumu-
lative intervals of 30, 90, 210, and 390 seconds. The binary
experimental workflow is presented in the schematic below
(Figure 2).
After the subsequent drying and representative split-
ting of all the products (four concentrates and 1 tailings),
handheld pXRF device was used to measure assays. The
device was calibrated using reference samples of differ-
ent content of both minerals. The obtained results were
adjusted based on calibration plots. For quartz, measured
Si was plotted against expected Si to obtain the calibration
function (Figure 3), while S was used for Pyrite (Figure 4).
Following the analytical procedures, entrainment was
estimated using an indirect approach, i.e., by using ratio of
quartz recovery and water recovery (Eq. 1). The interaction
between different hydrodynamic parameters was evaluated
using DoE-based statistical approaches.
RESULTS
Quartz recovery is plotted against water recovery at all the
different process conditions in Figure 5. Increase in Jg from
0.4 to 0.5 cm/s, resulted in an increase in quartz and water
recovery at all process conditions, except the test at high
collector concentration (50 g/t), low frother concentration
(30 g/t), and low Vt (4.7 m/s), where it had the opposite
effect. The test with low frother (30 g/t), low collector
(20 g/t), and high Vt (5.5 m/s) showed no significant dif-
ference in water and quartz recovery with an increase in Jg.
An increase in Vt from 4.7 to 5.5 m/s, higher quartz
and water recovery was noticed in almost all cases with an
exception of the tests performed at both, the low frother
(30 g/t) and low collector (20 g/t) conditions, where an
Table 1. Input variables for the binary campaign
Variable Minimum Center-point Maximum
Collector (PAX) concentration 20 g/t 35 g/t 50 g/t
Frother (MIBC) concentration 30 g/t 45 g/t 60 g/t
Superficial gas velocity (Jg) 0.40 cms–1 0.45 cms–1 0.5 cms–1
Impeller tip speed (Vt) 4.7 ms–1 5.1 ms–1 5.5 ms–1
Figure 1. Particle size distribution of Quartz and Pyrite used in the study as measured by wet sieving
of pyrite particles. Tests were performed on the 6-litre lab-
scale version of FLSmidth’s nextSTEP ™ rotor-stator in a
cylindrical tank. Four concentrates were collected at cumu-
lative intervals of 30, 90, 210, and 390 seconds. The binary
experimental workflow is presented in the schematic below
(Figure 2).
After the subsequent drying and representative split-
ting of all the products (four concentrates and 1 tailings),
handheld pXRF device was used to measure assays. The
device was calibrated using reference samples of differ-
ent content of both minerals. The obtained results were
adjusted based on calibration plots. For quartz, measured
Si was plotted against expected Si to obtain the calibration
function (Figure 3), while S was used for Pyrite (Figure 4).
Following the analytical procedures, entrainment was
estimated using an indirect approach, i.e., by using ratio of
quartz recovery and water recovery (Eq. 1). The interaction
between different hydrodynamic parameters was evaluated
using DoE-based statistical approaches.
RESULTS
Quartz recovery is plotted against water recovery at all the
different process conditions in Figure 5. Increase in Jg from
0.4 to 0.5 cm/s, resulted in an increase in quartz and water
recovery at all process conditions, except the test at high
collector concentration (50 g/t), low frother concentration
(30 g/t), and low Vt (4.7 m/s), where it had the opposite
effect. The test with low frother (30 g/t), low collector
(20 g/t), and high Vt (5.5 m/s) showed no significant dif-
ference in water and quartz recovery with an increase in Jg.
An increase in Vt from 4.7 to 5.5 m/s, higher quartz
and water recovery was noticed in almost all cases with an
exception of the tests performed at both, the low frother
(30 g/t) and low collector (20 g/t) conditions, where an
Table 1. Input variables for the binary campaign
Variable Minimum Center-point Maximum
Collector (PAX) concentration 20 g/t 35 g/t 50 g/t
Frother (MIBC) concentration 30 g/t 45 g/t 60 g/t
Superficial gas velocity (Jg) 0.40 cms–1 0.45 cms–1 0.5 cms–1
Impeller tip speed (Vt) 4.7 ms–1 5.1 ms–1 5.5 ms–1
Figure 1. Particle size distribution of Quartz and Pyrite used in the study as measured by wet sieving