3246 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
well. This makes further hydrometallurgical process more
challenging (Wilke et al., 2023b).
Second Air Classification
During the second air classification the electrode mixture
shall be separated in an aluminium and a copper concen-
trate. Therefore, an air speed of 4.7 m/s is applied to trans-
fer the aluminium to the light fraction and the copper to
the heavy fraction. As can be seen in Figure 6a the product
is contaminated by separator foil and by anode particles. As
expected, the remaining separator foil of the first air clas-
sification is now transferred to the light fraction. It is rea-
sonable that the prismatic cells with the lower recoveries
for the separator (Figure 3b) have greater share of it in the
aluminium product. Additionally, the aluminium concen-
trates of all batteries are contaminated with copper particles
from the anode (Figure 6a). This results from the smaller
and narrower particle size distribution of the copper par-
ticles (Kaas et al., 2024), thus the probability is higher to
transfer them to the light product. Regarding the recov-
ery of aluminium shown in Figure 6b, a clear difference
between cylindric and prismatic cells can be recognised.
For P1-P6 nearly all aluminium (93–97%) is regained in
the aluminium concentrate. In contrast, with types C2 and
C3, just slightly more than half of the aluminium in the
feed material is recovered in the light fraction (Figure 6b).
According to literature (Kaas et al., 2024) it is assumed that
the shape of the aluminium particles can be the reason for
that. The aluminium particles of the prismatic cells show a
more flake like structure. As a result, the inflow surface and
thus the resistance of the particles is greater, which means
that they can be discharged more easily into the light mate-
rial (Kaas et al., 2024).
As the recovery of the aluminium to the light fraction
is minor for the cylindric cells the impurity of cathode par-
ticles in the heavy product is greater. This becomes clear
when looking at the copper concentrate formed by the
heavy fraction. For C2 the aluminium in the copper frac-
tion makes up 29% and for C3 even 41% (Figure 7a). The
aluminium particles in the copper concentrate for C2 and
C3 are well spherodized, which is similar to the aluminium
particles found in the fraction of the prismatic cells. Thus,
Figure 5. Black mass output and composition (a) and recovery of elements to the
black mass (b) for the investigated cell types
well. This makes further hydrometallurgical process more
challenging (Wilke et al., 2023b).
Second Air Classification
During the second air classification the electrode mixture
shall be separated in an aluminium and a copper concen-
trate. Therefore, an air speed of 4.7 m/s is applied to trans-
fer the aluminium to the light fraction and the copper to
the heavy fraction. As can be seen in Figure 6a the product
is contaminated by separator foil and by anode particles. As
expected, the remaining separator foil of the first air clas-
sification is now transferred to the light fraction. It is rea-
sonable that the prismatic cells with the lower recoveries
for the separator (Figure 3b) have greater share of it in the
aluminium product. Additionally, the aluminium concen-
trates of all batteries are contaminated with copper particles
from the anode (Figure 6a). This results from the smaller
and narrower particle size distribution of the copper par-
ticles (Kaas et al., 2024), thus the probability is higher to
transfer them to the light product. Regarding the recov-
ery of aluminium shown in Figure 6b, a clear difference
between cylindric and prismatic cells can be recognised.
For P1-P6 nearly all aluminium (93–97%) is regained in
the aluminium concentrate. In contrast, with types C2 and
C3, just slightly more than half of the aluminium in the
feed material is recovered in the light fraction (Figure 6b).
According to literature (Kaas et al., 2024) it is assumed that
the shape of the aluminium particles can be the reason for
that. The aluminium particles of the prismatic cells show a
more flake like structure. As a result, the inflow surface and
thus the resistance of the particles is greater, which means
that they can be discharged more easily into the light mate-
rial (Kaas et al., 2024).
As the recovery of the aluminium to the light fraction
is minor for the cylindric cells the impurity of cathode par-
ticles in the heavy product is greater. This becomes clear
when looking at the copper concentrate formed by the
heavy fraction. For C2 the aluminium in the copper frac-
tion makes up 29% and for C3 even 41% (Figure 7a). The
aluminium particles in the copper concentrate for C2 and
C3 are well spherodized, which is similar to the aluminium
particles found in the fraction of the prismatic cells. Thus,
Figure 5. Black mass output and composition (a) and recovery of elements to the
black mass (b) for the investigated cell types