XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 547
A pilot plant was required to accurately evaluate closed
circuit VRM with grit extraction and magnetic separation.
Loesche designed, constructed, and successfully com-
missioned such a pilot plant and integrated it into their test
center in Duesseldorf.
Based on pilot testing by Loesche and earlier AG/Ball
mill piloting by Wood, the program produced the follow-
ing results when elevated to industrial scale.
Comparing whole ore milling to a common P80 85 µm
demonstrates a power benefit to the VRM circuit of 39%
(the industrial VRM circuit will only require 61% of the
AG/Ball mill power to achieve the same outcome). In this
comparison case there is no rejection of coarse non-mag-
netic tailings in either circuit.
Comparing the two circuits when both incorporate
RMS removal of non-magnetic waste before generating an
P80 85 µm product gives a power benefit of 41% to the
VRM. This is a similar power benefit magnitude in com-
parison to the open circuit case (the industrial VRM circuit
only requires 59% of the power of the AG/Ball circuit to
achieve the same outcome). Between 35 and 40% of the
feed is rejected as dry waste grits whilst Magnetite recovery
is kept constant in the case of the VRM.
To maximize the extend of ore processing that can be
performed dry the plant design for the Southdown project
was changed from AG/Ball Milling to a VRM circuit with
incorporated RMS.
The benefits of applying VRM technology extend
beyond power reduction, process-flexibility, and control to
important project factors such as reducing water consump-
tion and simplifying tailings management.
REFERENCES
Altun, D., Gerold, C., Benzer, H., Altun, O., and
Aydogan, N., (2015): ‘Copper ore grinding in a mobile
vertical roller mill pilot plant’, International Journal of
Mineral Processing, 136, p. 32–36.
David, D., Olwagen, D., Stanton, C., Gerold, C.,
Schmitz, C., Baaken, S., and Everitt, M., Pilot Testing
and Plant Design Comparison of Dry VRM Milling
plus Magnetic Separation with AG and Ball Milling
plus Magnetic Separation for Grange Resources’
Southdown Ore, (Conference paper), Comminution
23 Proceedings, Cape Town, South Africa.
Grange Resources 04.2023, https://www.grangeresources
.com.au/operations/southdown.
Jacobs, P., Seopa G., Mofokeng, M., Nienhaus, D.,
Gerold., C., and Mersmann, M., (2016, April): ‘16
Years of successful operation of a Loesche Vertical-
Roller-Mill Type LM 50.4 in a Hard Rock Application
at Foskor Pty (Ltd) in Phalaborwa (Conference paper)’,
Comminution 16 Proceedings, Cape Town, South Africa.
Reichert M., Gerold, C., Fredriksson, A., Adolfsson, G.,
and Lieberwirth, H., (2015): ‘Research of iron ore
grinding in a vertical-roller-mill‘, Minerals Engineering,
73, p. 109–115.
Schmitz, C., and Gerold, C., A Fundamental Change in
Approach ‐ Grinding Ores in Vertical Roller Mills:
Presentation of Test Results, IMCET 2019, Antalya,
Turkey, ISBN: 978-605-01-1273-3.
Stapelmann, M., Gerold, C., and Smith, J., Successful
Applications of Vertical-Roller-Mills in Phosphate
Processing, Proceedings Beneficiation of Phosphates
VIII, ISBN: 978-1-5108-7022-2.
Van Drunick, W., Gerold, C. and Palm, N., (2010):
‘Implementation of an energy efficient dry grinding
technology into an Anglo American zinc beneficiation
process [conference paper]’, XXV International Mineral
Processing Congress (IMPC) Proceedings, Brisbane,
QLD, Australia, p. 1333–1341.
A pilot plant was required to accurately evaluate closed
circuit VRM with grit extraction and magnetic separation.
Loesche designed, constructed, and successfully com-
missioned such a pilot plant and integrated it into their test
center in Duesseldorf.
Based on pilot testing by Loesche and earlier AG/Ball
mill piloting by Wood, the program produced the follow-
ing results when elevated to industrial scale.
Comparing whole ore milling to a common P80 85 µm
demonstrates a power benefit to the VRM circuit of 39%
(the industrial VRM circuit will only require 61% of the
AG/Ball mill power to achieve the same outcome). In this
comparison case there is no rejection of coarse non-mag-
netic tailings in either circuit.
Comparing the two circuits when both incorporate
RMS removal of non-magnetic waste before generating an
P80 85 µm product gives a power benefit of 41% to the
VRM. This is a similar power benefit magnitude in com-
parison to the open circuit case (the industrial VRM circuit
only requires 59% of the power of the AG/Ball circuit to
achieve the same outcome). Between 35 and 40% of the
feed is rejected as dry waste grits whilst Magnetite recovery
is kept constant in the case of the VRM.
To maximize the extend of ore processing that can be
performed dry the plant design for the Southdown project
was changed from AG/Ball Milling to a VRM circuit with
incorporated RMS.
The benefits of applying VRM technology extend
beyond power reduction, process-flexibility, and control to
important project factors such as reducing water consump-
tion and simplifying tailings management.
REFERENCES
Altun, D., Gerold, C., Benzer, H., Altun, O., and
Aydogan, N., (2015): ‘Copper ore grinding in a mobile
vertical roller mill pilot plant’, International Journal of
Mineral Processing, 136, p. 32–36.
David, D., Olwagen, D., Stanton, C., Gerold, C.,
Schmitz, C., Baaken, S., and Everitt, M., Pilot Testing
and Plant Design Comparison of Dry VRM Milling
plus Magnetic Separation with AG and Ball Milling
plus Magnetic Separation for Grange Resources’
Southdown Ore, (Conference paper), Comminution
23 Proceedings, Cape Town, South Africa.
Grange Resources 04.2023, https://www.grangeresources
.com.au/operations/southdown.
Jacobs, P., Seopa G., Mofokeng, M., Nienhaus, D.,
Gerold., C., and Mersmann, M., (2016, April): ‘16
Years of successful operation of a Loesche Vertical-
Roller-Mill Type LM 50.4 in a Hard Rock Application
at Foskor Pty (Ltd) in Phalaborwa (Conference paper)’,
Comminution 16 Proceedings, Cape Town, South Africa.
Reichert M., Gerold, C., Fredriksson, A., Adolfsson, G.,
and Lieberwirth, H., (2015): ‘Research of iron ore
grinding in a vertical-roller-mill‘, Minerals Engineering,
73, p. 109–115.
Schmitz, C., and Gerold, C., A Fundamental Change in
Approach ‐ Grinding Ores in Vertical Roller Mills:
Presentation of Test Results, IMCET 2019, Antalya,
Turkey, ISBN: 978-605-01-1273-3.
Stapelmann, M., Gerold, C., and Smith, J., Successful
Applications of Vertical-Roller-Mills in Phosphate
Processing, Proceedings Beneficiation of Phosphates
VIII, ISBN: 978-1-5108-7022-2.
Van Drunick, W., Gerold, C. and Palm, N., (2010):
‘Implementation of an energy efficient dry grinding
technology into an Anglo American zinc beneficiation
process [conference paper]’, XXV International Mineral
Processing Congress (IMPC) Proceedings, Brisbane,
QLD, Australia, p. 1333–1341.