XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2583
were collected at intervals of 10s, 20s, 30s, 45s, and 60s.
Subsequently, the collected samples underwent drying and
were analyzed separately.
Similarly, for the CustoFloat 390 scheme, an equiva-
lent set of procedures was followed to record flotation rates.
The dosage of CustoFloat 390 was maintained at 0.5 kg/t
for consistency in the experimental conditions. These com-
parative measurements served as a robust methodology for
evaluating the effectiveness of the newly devised reagent
scheme against the traditional approach.
Wettability Characterization
In the field of mineral process, the characterization of min-
eral surface wettability is frequently achieved through con-
tact angle measurements. However, due to the powdered
nature of the feed samples in this study, direct contact angle
measurements posed challenges(Ma et al., 2023 Wang et
al., 2023). Consequently, the capillary rise method was
employed, relying on the modified Washburn’s Equation,
which establishes a relationship between wetting liquid
mass and time, as illustrated in Equation (2):
cos m c
2
2
h
t c it =(2)
where m is the mass of penetrating liquid c is the con-
stant that depends on the inner diameter of the tube and
the power bed porosity ρ is liquid density γ is the liquid–
vapor surface tension θ is the contact angle η is the liquid
viscosity and t is the time of penetration.
Equation (2) highlights the positive correlation
between the mass of the penetrating liquid and cosθ, pro-
viding insight into the wettability of the particle samples.
In this study, a clean and dry plastic cylinder measuring 10
cm in length and 0.5 cm in inner diameter served as the
apparatus for contact angle measurement. The cylinder was
sealed with nonwoven fabric at the bottom to provide sup-
port for the particle bed. Two grams of dry phosphate pow-
der were manually compacted into the cylinder, which was
then tapped repeatedly until the powder reached a specified
level within the cylinder. Subsequently, the powder bed was
brought into contact with water in a separate container.
Due to the capillary effect within the powder bed, the
liquid ascended along the powder bed. At this point, the
weight of the liquid container was recorded as a function
of time. This experimental setup and methodology allowed
for the utilization of the capillary rise method to indirectly
determine the contact angle and assess the wettability of the
phosphate powder samples.
RESULTS &DISCUSSION
Flotation Results
In this study, a dosage range from 0.4 kg/t to 0.8 kg/t was
employed for both FA-1 and CustoFloat 390. An average
result of P2O5 flotation recovery and grade is provided in
Table 1, and the trends are illustrated in Figure 2, providing
the influence of varying reagent dosages.
The results presented in Table 1 and Figure 2 demon-
strate that the novel reagent scheme outperforms the tradi-
tional scheme in terms of P2O5 recovery. Achieving a P2O5
recovery of 96% necessitates only 0.4 kg/t of the new col-
lector, whereas approximately 0.8 kg/t of the conventional
collector is required to achieve a similar recovery level.
Overall, the increase in recovery using CustoFloat 390 was
consistently 2–3% higher than that achieved using the tra-
ditional FA-1 collector.
It is noteworthy, however, that CustoFloat 390 exhib-
ited slightly lower grades than traditional FA-1 across the
entire dosage range. This observed difference may be con-
sidered a trade-off, which is offset by the notable improve-
ment in recovery.
Flotation Kinetics Results
The flotation kinetics was launched to explore the flota-
tion efficiency difference between the two reagent schemes
deeply. The results and model fitting results are presented
in Figure 3.
Table 1. Flotation results with traditional FA1 and CustoFloat 390 schemes
Reagent
FA
kg/t
DO
kg/t
Feed
P
2 O
5 %
Concentrate Tailings Recovery
%P
2 O
5 %Wt. %P
2 O
5 %Wt.%
FA-1 0.40 0.15 15.68 28.58 51.13 2.17 48.87 93.24
0.60 0.23 15.62 28.57 51.70 1.75 48.30 94.59
0.80 0.3 15.65 28.31 52.78 1.49 47.22 95.50
CF 390 0.40 -15.42 27.37 54.64 1.28 45.79 96.20
0.60 -15.73 28.14 54.21 0.77 45.36 97.78
0.80 -15.61 27.48 56.19 0.38 43.81 98.93
were collected at intervals of 10s, 20s, 30s, 45s, and 60s.
Subsequently, the collected samples underwent drying and
were analyzed separately.
Similarly, for the CustoFloat 390 scheme, an equiva-
lent set of procedures was followed to record flotation rates.
The dosage of CustoFloat 390 was maintained at 0.5 kg/t
for consistency in the experimental conditions. These com-
parative measurements served as a robust methodology for
evaluating the effectiveness of the newly devised reagent
scheme against the traditional approach.
Wettability Characterization
In the field of mineral process, the characterization of min-
eral surface wettability is frequently achieved through con-
tact angle measurements. However, due to the powdered
nature of the feed samples in this study, direct contact angle
measurements posed challenges(Ma et al., 2023 Wang et
al., 2023). Consequently, the capillary rise method was
employed, relying on the modified Washburn’s Equation,
which establishes a relationship between wetting liquid
mass and time, as illustrated in Equation (2):
cos m c
2
2
h
t c it =(2)
where m is the mass of penetrating liquid c is the con-
stant that depends on the inner diameter of the tube and
the power bed porosity ρ is liquid density γ is the liquid–
vapor surface tension θ is the contact angle η is the liquid
viscosity and t is the time of penetration.
Equation (2) highlights the positive correlation
between the mass of the penetrating liquid and cosθ, pro-
viding insight into the wettability of the particle samples.
In this study, a clean and dry plastic cylinder measuring 10
cm in length and 0.5 cm in inner diameter served as the
apparatus for contact angle measurement. The cylinder was
sealed with nonwoven fabric at the bottom to provide sup-
port for the particle bed. Two grams of dry phosphate pow-
der were manually compacted into the cylinder, which was
then tapped repeatedly until the powder reached a specified
level within the cylinder. Subsequently, the powder bed was
brought into contact with water in a separate container.
Due to the capillary effect within the powder bed, the
liquid ascended along the powder bed. At this point, the
weight of the liquid container was recorded as a function
of time. This experimental setup and methodology allowed
for the utilization of the capillary rise method to indirectly
determine the contact angle and assess the wettability of the
phosphate powder samples.
RESULTS &DISCUSSION
Flotation Results
In this study, a dosage range from 0.4 kg/t to 0.8 kg/t was
employed for both FA-1 and CustoFloat 390. An average
result of P2O5 flotation recovery and grade is provided in
Table 1, and the trends are illustrated in Figure 2, providing
the influence of varying reagent dosages.
The results presented in Table 1 and Figure 2 demon-
strate that the novel reagent scheme outperforms the tradi-
tional scheme in terms of P2O5 recovery. Achieving a P2O5
recovery of 96% necessitates only 0.4 kg/t of the new col-
lector, whereas approximately 0.8 kg/t of the conventional
collector is required to achieve a similar recovery level.
Overall, the increase in recovery using CustoFloat 390 was
consistently 2–3% higher than that achieved using the tra-
ditional FA-1 collector.
It is noteworthy, however, that CustoFloat 390 exhib-
ited slightly lower grades than traditional FA-1 across the
entire dosage range. This observed difference may be con-
sidered a trade-off, which is offset by the notable improve-
ment in recovery.
Flotation Kinetics Results
The flotation kinetics was launched to explore the flota-
tion efficiency difference between the two reagent schemes
deeply. The results and model fitting results are presented
in Figure 3.
Table 1. Flotation results with traditional FA1 and CustoFloat 390 schemes
Reagent
FA
kg/t
DO
kg/t
Feed
P
2 O
5 %
Concentrate Tailings Recovery
%P
2 O
5 %Wt. %P
2 O
5 %Wt.%
FA-1 0.40 0.15 15.68 28.58 51.13 2.17 48.87 93.24
0.60 0.23 15.62 28.57 51.70 1.75 48.30 94.59
0.80 0.3 15.65 28.31 52.78 1.49 47.22 95.50
CF 390 0.40 -15.42 27.37 54.64 1.28 45.79 96.20
0.60 -15.73 28.14 54.21 0.77 45.36 97.78
0.80 -15.61 27.48 56.19 0.38 43.81 98.93