2582 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
P2O5. Subsequently, the feed was apportioned into 850 g
charges, equivalent to approximately 700 g of dry weight,
to facilitate the subsequent flotation tests.
Reagents
CustoFloat 390 was supplied by Arkema-ArrMaz. Other
key reagents, namely fatty acid (FA-1), soda ash, and
ammonia, utilized for pH modification, as well as fuel oil/
diesel, employed as secondary collectors, were sourced as
commercially graded materials from the mineral process-
ing plant of the customer. The consistency in the quality of
these reagents ensures reliability and accuracy in the experi-
mental procedures, aligning with industry standards and
best practices.
Flotation
In the conventional rougher flotation procedure, the con-
ditioning of the feed occurred in a 2 L round vessel with
a solids %of 70%, incorporating the collector FA-1 and
diesel (mass ratio of 8:3) at an alkaline pH. The dosages of
the collector were set as designed and shown in the result
part. The pH adjustment was achieved using either soda
ash as a modifier. The conditioning process was maintained
for 2 minutes. Subsequently, the conditioned slurry was
transferred to a 2.5 L Denver flotation cell. Additional
water was introduced until it reached a level just below ¼”
from the overflow lip of the cell. Following this, the air
valve was activated, initiating the flotation process with an
impeller rotation speed of 1200 rpm. The flotation process
was extended for 1–2 minutes. Subsequently, both the float
and sink fractions underwent dewatering, drying, weigh-
ing, and thorough analysis. The overall flow sheet detailing
these sequential steps is depicted in Figure 1 (a).
This conventional rougher flotation process served as
the benchmark against which the newly developed reagent
schemes were rigorously evaluated and compared. Notably,
when employing Custofloat 390, the necessity for a pH
modifier or diesel was entirely obviated, streamlining the
flotation process. All other operating conditions remained
consistent. The modified flow sheet is visually represented
in Figure 1 (b), illustrating the simplified and environmen-
tally friendly alterations introduced by the application of
Custofloat 390 in the phosphate flotation circuit.
Flotation Kinetics
Kinetic models that draw parallels with the chemical
reactor analogy and conceptualize flotation as a reaction
between bubbles and particles have garnered significant
attention(Polat and Chander, 2000). The general equation
for flotation is commonly expressed as Equation (1):
d
dR^th
k
t
=^th (1)
where R(t) is flotation recovery at time t. And k(t) is a
pseudo rate constant that depends on various parameters
governing the flotation process, and may vary with time,
but it could also be considered as constant for simplification
purposes. A higher k represents a higher flotation kinetics.
Where R(t) signifies the flotation recovery at time t,
and k(t) represents a pseudo rate constant influenced by
multiple parameters governing the flotation process. It’s
important to note that k(t) may exhibit temporal variation.
However, for the sake of simplification, it can be treated as a
constant. A higher k value corresponds to elevated flotation
kinetics, indicative of a more rapid and efficient flotation
process. This simplification allows for a clearer representa-
tion and interpretation of the kinetics involved in the flota-
tion phenomena under investigation.
To assess and compare flotation efficiency, the flotation
rates of both the traditional scheme and the CustoFloat
390 scheme were systematically measured. In the case of
the traditional scheme, dosages of FA-1 and diesel were
fixed at 0.5 kg/t and 0.2 kg/t, respectively. Adhering to the
flotation flowsheet delineated in Figure 1(a), froth products
Feed
CF 390
Concentrate
Flotation
(b)
Tailings
(a)
Tailings
Feed
Soda ash
pH 9.3
Fatty Acid
Diesel
Concentrate
Flotation
Figure 1. Lab phosphate rougher flotation flowsheet: (a) traditional reagent scheme with
diesel and soda ash (b) CustoFloat 390 scheme without fuel oil and soda ash
P2O5. Subsequently, the feed was apportioned into 850 g
charges, equivalent to approximately 700 g of dry weight,
to facilitate the subsequent flotation tests.
Reagents
CustoFloat 390 was supplied by Arkema-ArrMaz. Other
key reagents, namely fatty acid (FA-1), soda ash, and
ammonia, utilized for pH modification, as well as fuel oil/
diesel, employed as secondary collectors, were sourced as
commercially graded materials from the mineral process-
ing plant of the customer. The consistency in the quality of
these reagents ensures reliability and accuracy in the experi-
mental procedures, aligning with industry standards and
best practices.
Flotation
In the conventional rougher flotation procedure, the con-
ditioning of the feed occurred in a 2 L round vessel with
a solids %of 70%, incorporating the collector FA-1 and
diesel (mass ratio of 8:3) at an alkaline pH. The dosages of
the collector were set as designed and shown in the result
part. The pH adjustment was achieved using either soda
ash as a modifier. The conditioning process was maintained
for 2 minutes. Subsequently, the conditioned slurry was
transferred to a 2.5 L Denver flotation cell. Additional
water was introduced until it reached a level just below ¼”
from the overflow lip of the cell. Following this, the air
valve was activated, initiating the flotation process with an
impeller rotation speed of 1200 rpm. The flotation process
was extended for 1–2 minutes. Subsequently, both the float
and sink fractions underwent dewatering, drying, weigh-
ing, and thorough analysis. The overall flow sheet detailing
these sequential steps is depicted in Figure 1 (a).
This conventional rougher flotation process served as
the benchmark against which the newly developed reagent
schemes were rigorously evaluated and compared. Notably,
when employing Custofloat 390, the necessity for a pH
modifier or diesel was entirely obviated, streamlining the
flotation process. All other operating conditions remained
consistent. The modified flow sheet is visually represented
in Figure 1 (b), illustrating the simplified and environmen-
tally friendly alterations introduced by the application of
Custofloat 390 in the phosphate flotation circuit.
Flotation Kinetics
Kinetic models that draw parallels with the chemical
reactor analogy and conceptualize flotation as a reaction
between bubbles and particles have garnered significant
attention(Polat and Chander, 2000). The general equation
for flotation is commonly expressed as Equation (1):
d
dR^th
k
t
=^th (1)
where R(t) is flotation recovery at time t. And k(t) is a
pseudo rate constant that depends on various parameters
governing the flotation process, and may vary with time,
but it could also be considered as constant for simplification
purposes. A higher k represents a higher flotation kinetics.
Where R(t) signifies the flotation recovery at time t,
and k(t) represents a pseudo rate constant influenced by
multiple parameters governing the flotation process. It’s
important to note that k(t) may exhibit temporal variation.
However, for the sake of simplification, it can be treated as a
constant. A higher k value corresponds to elevated flotation
kinetics, indicative of a more rapid and efficient flotation
process. This simplification allows for a clearer representa-
tion and interpretation of the kinetics involved in the flota-
tion phenomena under investigation.
To assess and compare flotation efficiency, the flotation
rates of both the traditional scheme and the CustoFloat
390 scheme were systematically measured. In the case of
the traditional scheme, dosages of FA-1 and diesel were
fixed at 0.5 kg/t and 0.2 kg/t, respectively. Adhering to the
flotation flowsheet delineated in Figure 1(a), froth products
Feed
CF 390
Concentrate
Flotation
(b)
Tailings
(a)
Tailings
Feed
Soda ash
pH 9.3
Fatty Acid
Diesel
Concentrate
Flotation
Figure 1. Lab phosphate rougher flotation flowsheet: (a) traditional reagent scheme with
diesel and soda ash (b) CustoFloat 390 scheme without fuel oil and soda ash