XXXI International Mineral Processing Congress 2024 Proceedings Page 3801 (3825 of 3836)

3967
Simulation, Design, and Model Validation for the Conjugate
Anvil Hammer Mill (CAHM) Platform Using Rocky DEM
S.W. Wilson
ReThink Milling Inc., Toronto, ON, Canada
M. Mousaviraad, S. Ghorbani, R. Stephens, L. Nordell
CTTI, Bellingham, WA, USA
ABSTRACT: The Conjugate Anvil Hammer Mill (CAHM) is a novel platform technology that includes two
prototype rock grinding machines. Both prototypes have demonstrated significant energy savings and other
performance benefits compared to conventional HPGR and Ball Mill technology in similar services. CAHM
technology was developed through an extensive DEM simulation-based design and optimization program using
Ansys Rocky DEM software. Simulation validation studies for the HPGR provided confidence to proceed with
detailed design and fabrication of prototypes based solely on the DEM work. The MonoRoll is a 2 t/h retrofit
for a ~1 m diameter pilot scale ball mill. The CAHM Mark 1 Prototype is a nominally 60 t/h machine and has
a 1.4 m inner diameter shell working surface. Testing results for both machines are discussed and compared to
initial simulation work.
INTRODUCTION
Comminution is the process of reducing rock particle sizes.
It is a critical operation in many industries, including min-
ing and mineral processing. Despite consuming approxi-
mately 3% of the world’s generated electric power (Mining
Technology, 2019), the technology has seen little advance-
ment. The Canadian Mining Innovation Council (CMIC)
identified the Conjugate Anvil Hammer Mill (CAHM)
(Nordell and Potapov, 2011) in a global technology search
(CMIC, 2016) as the most likely new comminution tech-
nology to reduce comminution energy consumption by
over 50% compared with currently available technolo-
gies and would benefit from CMIC’s efforts to partner to
advance the technology towards full commercialization.
CAHM technology is based on the work of Dr Klaus
Schönert (1996). Schönert identified single particle (or
thin particle bed) compression breakage between parallel
plates as the most energy-efficient breakage mechanism.
One significant feature of single particle and thin particle
bed breakage is that particles are “unconfined”—meaning
that there is void space around them where fragments can
release/break without consuming additional energy as they
compact against other fragments.
Schönert’s work led to the development of High-
Pressure Grinding Rolls (HPGR) technology, which has
demonstrated a significant energy advantage over the min-
erals industry’s traditional tumbling mills in similar service.
Unfortunately, HPGRs still break relatively thick particle
beds, and fragmentation of larger particles is constrained
(or confined) by finer particles that surround them. The
broken fragments are often compressed into “pancakes” or
“hockey pucks” that often must be deagglomerated using
additional equipment.

Previous Page Next Page

Extracted Text (may have errors)

3967
Simulation, Design, and Model Validation for the Conjugate
Anvil Hammer Mill (CAHM) Platform Using Rocky DEM
S.W. Wilson
ReThink Milling Inc., Toronto, ON, Canada
M. Mousaviraad, S. Ghorbani, R. Stephens, L. Nordell
CTTI, Bellingham, WA, USA
ABSTRACT: The Conjugate Anvil Hammer Mill (CAHM) is a novel platform technology that includes two
prototype rock grinding machines. Both prototypes have demonstrated significant energy savings and other
performance benefits compared to conventional HPGR and Ball Mill technology in similar services. CAHM
technology was developed through an extensive DEM simulation-based design and optimization program using
Ansys Rocky DEM software. Simulation validation studies for the HPGR provided confidence to proceed with
detailed design and fabrication of prototypes based solely on the DEM work. The MonoRoll is a 2 t/h retrofit
for a ~1 m diameter pilot scale ball mill. The CAHM Mark 1 Prototype is a nominally 60 t/h machine and has
a 1.4 m inner diameter shell working surface. Testing results for both machines are discussed and compared to
initial simulation work.
INTRODUCTION
Comminution is the process of reducing rock particle sizes.
It is a critical operation in many industries, including min-
ing and mineral processing. Despite consuming approxi-
mately 3% of the world’s generated electric power (Mining
Technology, 2019), the technology has seen little advance-
ment. The Canadian Mining Innovation Council (CMIC)
identified the Conjugate Anvil Hammer Mill (CAHM)
(Nordell and Potapov, 2011) in a global technology search
(CMIC, 2016) as the most likely new comminution tech-
nology to reduce comminution energy consumption by
over 50% compared with currently available technolo-
gies and would benefit from CMIC’s efforts to partner to
advance the technology towards full commercialization.
CAHM technology is based on the work of Dr Klaus
Schönert (1996). Schönert identified single particle (or
thin particle bed) compression breakage between parallel
plates as the most energy-efficient breakage mechanism.
One significant feature of single particle and thin particle
bed breakage is that particles are “unconfined”—meaning
that there is void space around them where fragments can
release/break without consuming additional energy as they
compact against other fragments.
Schönert’s work led to the development of High-
Pressure Grinding Rolls (HPGR) technology, which has
demonstrated a significant energy advantage over the min-
erals industry’s traditional tumbling mills in similar service.
Unfortunately, HPGRs still break relatively thick particle
beds, and fragmentation of larger particles is constrained
(or confined) by finer particles that surround them. The
broken fragments are often compressed into “pancakes” or
“hockey pucks” that often must be deagglomerated using
additional equipment.

Help

3957
Comminution
Comminution Technology/Innovation

Previous Page Next Page

Extracted Text (may have errors)

3968 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
CAHM and MonoRoll are part of a new generation of
equipment designed to maximize the transfer of commi-
nution energy into particle fracture. In both machines, as
depicted in Figure 1, an inner hammer roll rotates within a
concentric, but offset anvil shell. As drums rotate together,
particles are caught and drawn into a decreasing gap
between the roll surfaces. The largest particles are broken
first because broken fragments are released from the mill as
soon as they are produced ensuring an unconfined breakage
environment.
The CAHM prototype resembles a horizontal slice
from a gyratory crusher turned on its side. Undersized par-
ticles (including feed particles) exit immediately through
slots in the anvil. In contrast, the MonoRoll is similar to a
ball mill where the grinding media has been replaced with a
single hammer roll rotating inside the anvil shell, as shown
in Figure 2. Particles enter one end of the mill and are pro-
gressively guided or swept along the mill. Ore particles pass
under the hammer multiple times, undergoing multiple
stages of unconfined compressive fracture, before exiting
the other end of the machine.
Both machines benefit from a longer comminution arc,
slower compression rate, and greater nip angle capture zone
as the rock is broken between converging concave surfaces
(Nordell et al., 2016), contrasting the converging convex
surfaces of the HPGR.
CAHM and MonoRoll represent significant advance-
ments in the field of comminution. They offer the poten-
tial for substantial energy savings, operational efficiencies
through circuit simplification, and reduced costs with the
elimination of grinding media when compared to com-
mon, conventional comminution circuits.
Discrete Element Method (DEM) modeling using
Ansys’ Rocky DEM software was the primary design tool
for both CAHM and MonoRoll. This high-fidelity model-
ing approach simulates the complex interactions between
individual particles and predicts individual particle break-
age. It enabled design optimization for maximum energy
efficiency and operational effectiveness.
In this paper, we present the design and optimization
of the CAHM technology in two prototype machines based
on DEM simulations. HPGR simulations are presented as
benchmark comparisons. All three pieces of equipment
-the CAHM, MonoRoll, and HPGR—have been physi-
cally tested at pilot scale and the results from these tests are
Figure 1. Concept drawing of the CAHM design principles
Figure 2. MonoRoll concept model with ore feeding on left-
hand side and discharging on right-hand side

Previous Page Next Page

Extracted Text (may have errors)

3968 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
CAHM and MonoRoll are part of a new generation of
equipment designed to maximize the transfer of commi-
nution energy into particle fracture. In both machines, as
depicted in Figure 1, an inner hammer roll rotates within a
concentric, but offset anvil shell. As drums rotate together,
particles are caught and drawn into a decreasing gap
between the roll surfaces. The largest particles are broken
first because broken fragments are released from the mill as
soon as they are produced ensuring an unconfined breakage
environment.
The CAHM prototype resembles a horizontal slice
from a gyratory crusher turned on its side. Undersized par-
ticles (including feed particles) exit immediately through
slots in the anvil. In contrast, the MonoRoll is similar to a
ball mill where the grinding media has been replaced with a
single hammer roll rotating inside the anvil shell, as shown
in Figure 2. Particles enter one end of the mill and are pro-
gressively guided or swept along the mill. Ore particles pass
under the hammer multiple times, undergoing multiple
stages of unconfined compressive fracture, before exiting
the other end of the machine.
Both machines benefit from a longer comminution arc,
slower compression rate, and greater nip angle capture zone
as the rock is broken between converging concave surfaces
(Nordell et al., 2016), contrasting the converging convex
surfaces of the HPGR.
CAHM and MonoRoll represent significant advance-
ments in the field of comminution. They offer the poten-
tial for substantial energy savings, operational efficiencies
through circuit simplification, and reduced costs with the
elimination of grinding media when compared to com-
mon, conventional comminution circuits.
Discrete Element Method (DEM) modeling using
Ansys’ Rocky DEM software was the primary design tool
for both CAHM and MonoRoll. This high-fidelity model-
ing approach simulates the complex interactions between
individual particles and predicts individual particle break-
age. It enabled design optimization for maximum energy
efficiency and operational effectiveness.
In this paper, we present the design and optimization
of the CAHM technology in two prototype machines based
on DEM simulations. HPGR simulations are presented as
benchmark comparisons. All three pieces of equipment
-the CAHM, MonoRoll, and HPGR—have been physi-
cally tested at pilot scale and the results from these tests are
Figure 1. Concept drawing of the CAHM design principles
Figure 2. MonoRoll concept model with ore feeding on left-
hand side and discharging on right-hand side

Page 1Plenary Program click to expand contents

Page 22Keynote Presentations click to expand contents

Page 163Innovation and R&D click to expand contents

Page 445Dry Processing click to expand contents

Page 562Water Management click to expand contents

Page 756Human Capital click to expand contents

Page 808Process Control, Modeling, and Simulation click to expand contents

Page 1126Strategic Minerals click to expand contents

Page 1325Geometallurgy and Process Mineralogy click to expand contents

Page 1535Extractive Metallurgy click to expand contents

Page 1842Physical Separations click to expand contents

Page 2016Flotation click to expand contents

Page 3021Energy Minerals click to expand contents

Page iTailings click to expand contents

Page 3420Plant Design click to expand contents

Page 3526Comminution click to expand contents

Extracted Text (may have errors)

Help

loading

Extracted Text (may have errors)

Extracted Text (may have errors)