XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 841
mill when ROM A and ROM B type of iron ore fed to
grinding circuit.
Concurrently, the presence of this particular hard ore
(ROM B) as depicted in table 2, has precipitated additional
complications, notably a substantial increase in media wear
rate within the mill. The heigh wear rate of media has subse-
quently engendered a decline in the effective catracting and
cascading forces exerted by the media on the incoming feed
ore which is responsible for fine grinding. Following a com-
prehensive analysis of operational data, it has been identi-
fied that the elevated media wear rate is directly attributed
to the presence of hard ore. Our operational observations
suggest a reduction in the effective volumetric availability
of media during continuous mill operation. This reduced
availability poses a challenge in accurately quantifying the
required top-up of media, as it could potentially impact
the ideal filling level within the mill. To address this chal-
lenge, a strategic decision has been made to predict the
media wear rate and determine the effective loss of media
occurring during plant operation. Subsequently, this quan-
tification will aid in accurately assessing the requisite top-
up quantity. In pursuing this objective, a methodology
centered on first principles has been adopted, as outlined in
the methodology section. This approach integrates insights
from comprehensive literature reviews and aims to provide
a robust framework for estimating media wear rates and
optimizing the management of media top-up requirements
within the operational setting.
Methodology
The methodology involves utilizing first-principle math-
ematical modeling to predict media wear in a ball mill. The
ball mill, with dimensions 12 m in length and 5.5 m in
diameter, undergoes a design phase followed by subdivision
through standard meshing criteria with mesh sizes of 100 ×
100 mm. Media, adhering to Bond’s law, is introduced into
the mill, considering an initial volumetric filling of 26% as
represented in Figure 2.
Table 1. Chemical and physical characteristic of iron ore
Iron Ore TFe, %SiO
2 %Al
2 O
3 ,%LOI, %
Mean
Size, mm BWI
ROM A 62–63.5 1.5–2.5 1.8–2.8 3–5 5–6.5 7–9
ROM B 61–63 1.7–3 1.8–2.8 3.5–5.5 5.5–7 11.5–13.5
Source: Plant operational data (Tata Steel Iron ore Mines)
Table 2. Grinding circuit performance
Iron Ore
Mill Power,
KW
Mill Current,
Amps
Throughput,
TPH
Recirculation,
%
45 Microns
Passing, %
ROM A 5700 860 560 180 75
ROM B 5900 875 520 230 70
Source: Plant operational data (Tata Steel pellet plant)
Figure 2. Schematic of ball mill and media available inside the mill
mill when ROM A and ROM B type of iron ore fed to
grinding circuit.
Concurrently, the presence of this particular hard ore
(ROM B) as depicted in table 2, has precipitated additional
complications, notably a substantial increase in media wear
rate within the mill. The heigh wear rate of media has subse-
quently engendered a decline in the effective catracting and
cascading forces exerted by the media on the incoming feed
ore which is responsible for fine grinding. Following a com-
prehensive analysis of operational data, it has been identi-
fied that the elevated media wear rate is directly attributed
to the presence of hard ore. Our operational observations
suggest a reduction in the effective volumetric availability
of media during continuous mill operation. This reduced
availability poses a challenge in accurately quantifying the
required top-up of media, as it could potentially impact
the ideal filling level within the mill. To address this chal-
lenge, a strategic decision has been made to predict the
media wear rate and determine the effective loss of media
occurring during plant operation. Subsequently, this quan-
tification will aid in accurately assessing the requisite top-
up quantity. In pursuing this objective, a methodology
centered on first principles has been adopted, as outlined in
the methodology section. This approach integrates insights
from comprehensive literature reviews and aims to provide
a robust framework for estimating media wear rates and
optimizing the management of media top-up requirements
within the operational setting.
Methodology
The methodology involves utilizing first-principle math-
ematical modeling to predict media wear in a ball mill. The
ball mill, with dimensions 12 m in length and 5.5 m in
diameter, undergoes a design phase followed by subdivision
through standard meshing criteria with mesh sizes of 100 ×
100 mm. Media, adhering to Bond’s law, is introduced into
the mill, considering an initial volumetric filling of 26% as
represented in Figure 2.
Table 1. Chemical and physical characteristic of iron ore
Iron Ore TFe, %SiO
2 %Al
2 O
3 ,%LOI, %
Mean
Size, mm BWI
ROM A 62–63.5 1.5–2.5 1.8–2.8 3–5 5–6.5 7–9
ROM B 61–63 1.7–3 1.8–2.8 3.5–5.5 5.5–7 11.5–13.5
Source: Plant operational data (Tata Steel Iron ore Mines)
Table 2. Grinding circuit performance
Iron Ore
Mill Power,
KW
Mill Current,
Amps
Throughput,
TPH
Recirculation,
%
45 Microns
Passing, %
ROM A 5700 860 560 180 75
ROM B 5900 875 520 230 70
Source: Plant operational data (Tata Steel pellet plant)
Figure 2. Schematic of ball mill and media available inside the mill