XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3803
fines generation leads to higher recoveries (Burchardt &
Mackert, 2019).
Additional Secondary Benefits of HPGR
Several other HPGR benefits have been documented. An
indirect energy savings opportunity is reducing embodied
energy by eliminating the need to purchase and transport
grinding media consumed in SAG milling (Ballantyne
2019). The use and replacement of grinding media has
been incorporated as a component of a comminution cir-
cuits embodied energy as it requires energy and processing
to create and then transport the grinding media (Ballantyne
2019). Additionally, HPGR’s ability to handle high pebble
recycling, low head grades, small site footprint, changes in
ore characteristics, and a tendency to outperform model
predicted capacities work in HPGR’s favor (Klymowsky
2006 Burchardt &Mackert, 2019 van de Vijfeijken et al.,
2023). The tendency for HPGR to have operation capaci-
ties greater than those predicted may also be working in
HGPR’s favor under investment conditions where AG/
SAG installations have recently experienced below pre-
dicted operational throughputs (Burchardt et al., 2011
Staples et al., 2015).
Operationally, HPGR benefits from stability, rapid pro-
duction ramp-up, and greater time availability. Operations
have noted great operational stability of their units
(Burchardt &Mackert, 2019 Haines &Geoghegan, 2023
Lovatt et al., 2023 Saramak et al., 2010). Even in response
to process upsets the restarting of HPGR units has shown
rapid stabilization to expected performance (Burchardt et
al., 2011). HPGR has also been shown to be less sensitive
to changes in feed material characteristics as roll speed and
grinding pressure can be rapidly adjusted to accommodate
changing conditions (Burchardt &Mackert, 2019 van de
Vijfeijken et al., 2023). Reports show that HPGR time
availability outperforms other technologies by reaching
94% on stream and greater (Burchardt &Mackert, 2019
Klymowsky 2003 Patzelt et al., 2001). HPGR’s ability to
rapidly achieve full production is enhanced, with some
examples stating full production has occurred within two
months (Klymowsky 2003). The shorter startup time of
HPGR/ball mill circuits can contribute to the cost effec-
tiveness of these circuits over SABC (Burchardt et al.,
2011). Finally, HPGR has been found to be relatively sim-
pler to run operationally (Burchardt &Mackert, 2019
Klymowsky 2003).
HURDLES IN THE ADPTION OF HPGR
Lack of Experienced Personnel
Alongside advantageous developments the hurdles of
HPGR have been identified and evaluated (Tbl. 1). Concern
regarding the availability of experienced personnel was a
concern (Amelunxen 2011). Generating a deeper pool of
experienced personnel is a challenge during the introduc-
tion of all new technologies. There being a greater number
of trained personnel for SAG milling compared to HPGR
was brought up as late as 2015 (Davaanyam 2015). Given
the evident number of installations confirmed for diamond
mining in 2005 combined with the four hundred instal-
lations for the cement industry by 2007 it is reasonable
to assume that by the mid-2000s this limitation had been
fundamentally overcome (M. J. Daniel &Morley, 2010).
Reports from 2010 and onward indicate that HPGR man-
ufacturers have developed sufficient knowledge to validate
design criteria, develop scale-up factors, and understand
best practices supporting the idea that any lack of expertise
has been overcome (Burchardt et al., 2011 Burchardt &
Mackert, 2019 van de Vijfeijken et al., 2023).
Roll Liner Wear
Concerns regarding limited liner lifetime due to wear
from abrasive ores appeared in the early 1990s (Patzelt et
al., 2001 Seidel et al., 2006). Cyprus Sierrita’s decommis-
sioning due to the low liner life, despite great optimism for
continued improvement, serves as a testament to the seri-
ousness of this concern (Davaanyam 2015 L. Thompsen
et al., 1996 L. G. Thompsen1997). This optimism was
warranted as limited roll life has been overcome due to
advancement in liner designs, particularly the introduc-
tion of studs (Figure 4) and cheek plates (M. J. Daniel &
Morley, 2010 Klymowsky 2006 McIvor 1997). The devel-
opment of abrasion testing capable of reliably predicting
wear was a supporting factor (Burchardt et al., 2011).
Since the introduction of studs, roll life is limited by
either roll abrasion or stud breakage (Burchardt &Mackert,
2019). Excessive stud breakage is caused by coarse and very
competent ore can limit factor roll life, rather than wear
itself (Burchardt et al., 2011 Burchardt &Mackert, 2019).
The relationship between ore properties of abrasiveness,
feed size, feed size to gap ratio and stud characteristics of
length, hardness, and/or composition determine the rate of
stud breakage (Figure 5) (Burchardt &Mackert, 2019).
Alongside the development of studs, roll and cheek
plate life steadily improved. Roll life now reliably reaches
fines generation leads to higher recoveries (Burchardt &
Mackert, 2019).
Additional Secondary Benefits of HPGR
Several other HPGR benefits have been documented. An
indirect energy savings opportunity is reducing embodied
energy by eliminating the need to purchase and transport
grinding media consumed in SAG milling (Ballantyne
2019). The use and replacement of grinding media has
been incorporated as a component of a comminution cir-
cuits embodied energy as it requires energy and processing
to create and then transport the grinding media (Ballantyne
2019). Additionally, HPGR’s ability to handle high pebble
recycling, low head grades, small site footprint, changes in
ore characteristics, and a tendency to outperform model
predicted capacities work in HPGR’s favor (Klymowsky
2006 Burchardt &Mackert, 2019 van de Vijfeijken et al.,
2023). The tendency for HPGR to have operation capaci-
ties greater than those predicted may also be working in
HGPR’s favor under investment conditions where AG/
SAG installations have recently experienced below pre-
dicted operational throughputs (Burchardt et al., 2011
Staples et al., 2015).
Operationally, HPGR benefits from stability, rapid pro-
duction ramp-up, and greater time availability. Operations
have noted great operational stability of their units
(Burchardt &Mackert, 2019 Haines &Geoghegan, 2023
Lovatt et al., 2023 Saramak et al., 2010). Even in response
to process upsets the restarting of HPGR units has shown
rapid stabilization to expected performance (Burchardt et
al., 2011). HPGR has also been shown to be less sensitive
to changes in feed material characteristics as roll speed and
grinding pressure can be rapidly adjusted to accommodate
changing conditions (Burchardt &Mackert, 2019 van de
Vijfeijken et al., 2023). Reports show that HPGR time
availability outperforms other technologies by reaching
94% on stream and greater (Burchardt &Mackert, 2019
Klymowsky 2003 Patzelt et al., 2001). HPGR’s ability to
rapidly achieve full production is enhanced, with some
examples stating full production has occurred within two
months (Klymowsky 2003). The shorter startup time of
HPGR/ball mill circuits can contribute to the cost effec-
tiveness of these circuits over SABC (Burchardt et al.,
2011). Finally, HPGR has been found to be relatively sim-
pler to run operationally (Burchardt &Mackert, 2019
Klymowsky 2003).
HURDLES IN THE ADPTION OF HPGR
Lack of Experienced Personnel
Alongside advantageous developments the hurdles of
HPGR have been identified and evaluated (Tbl. 1). Concern
regarding the availability of experienced personnel was a
concern (Amelunxen 2011). Generating a deeper pool of
experienced personnel is a challenge during the introduc-
tion of all new technologies. There being a greater number
of trained personnel for SAG milling compared to HPGR
was brought up as late as 2015 (Davaanyam 2015). Given
the evident number of installations confirmed for diamond
mining in 2005 combined with the four hundred instal-
lations for the cement industry by 2007 it is reasonable
to assume that by the mid-2000s this limitation had been
fundamentally overcome (M. J. Daniel &Morley, 2010).
Reports from 2010 and onward indicate that HPGR man-
ufacturers have developed sufficient knowledge to validate
design criteria, develop scale-up factors, and understand
best practices supporting the idea that any lack of expertise
has been overcome (Burchardt et al., 2011 Burchardt &
Mackert, 2019 van de Vijfeijken et al., 2023).
Roll Liner Wear
Concerns regarding limited liner lifetime due to wear
from abrasive ores appeared in the early 1990s (Patzelt et
al., 2001 Seidel et al., 2006). Cyprus Sierrita’s decommis-
sioning due to the low liner life, despite great optimism for
continued improvement, serves as a testament to the seri-
ousness of this concern (Davaanyam 2015 L. Thompsen
et al., 1996 L. G. Thompsen1997). This optimism was
warranted as limited roll life has been overcome due to
advancement in liner designs, particularly the introduc-
tion of studs (Figure 4) and cheek plates (M. J. Daniel &
Morley, 2010 Klymowsky 2006 McIvor 1997). The devel-
opment of abrasion testing capable of reliably predicting
wear was a supporting factor (Burchardt et al., 2011).
Since the introduction of studs, roll life is limited by
either roll abrasion or stud breakage (Burchardt &Mackert,
2019). Excessive stud breakage is caused by coarse and very
competent ore can limit factor roll life, rather than wear
itself (Burchardt et al., 2011 Burchardt &Mackert, 2019).
The relationship between ore properties of abrasiveness,
feed size, feed size to gap ratio and stud characteristics of
length, hardness, and/or composition determine the rate of
stud breakage (Figure 5) (Burchardt &Mackert, 2019).
Alongside the development of studs, roll and cheek
plate life steadily improved. Roll life now reliably reaches