COMMINUTION & CRUSHING
The primaries
thyssenkrupp Industrial Solutions has been on a winning streak in Australia of late with its primary
gyratory crushers.
Late last year, it announced it would install the first above ground jaw gyratory crusher in the
country at the Roy Hill iron ore mine, in the Pilbara of Western Australia. This followed on the heels
of signing a contract to deliver the world’s first “double-mouth” jaw-gyratory crusher to China
Molybdenum’s majority-owned Northparkes underground copper-gold mine, in New South Wales,
and agreeing to fit a large primary gyratory crusher at OZ Minerals’ Carrapateena copper-gold mine,
in South Australia.
While the company’s large primary gyratory crushers were designed for underground block caves,
the Roy Hill installation, which will enable the iron ore miner to crush “large oversize material” that
conventional machines could not accommodate, shows they may have a home above ground too.
IM touched base with Luke Bennett, National Sales Manager – Strategic Accounts, thyssenkrupp
Industrial Solutions (Australia), to find out more.
IM: Why is the Roy Hill installation the first above-ground installation in Australia?
LB: The jaw gyratory crusher was designed with underground block caving in mind. With block
caving, the amount of large rocks is significantly higher than above-ground drill and blast mining.
The only reason why this is the first above-ground installation is miners have typically stuck with
the same plant and machine design as previous, which has been a standard gyratory crusher for
many years. For a long time, miners have accepted the fact they will need to use a rock breaker for
some rocks that won’t fit into the crusher.
However, now throughput is king. As the downtime experienced with rock breaking can lead to
throughput drops, clients are looking to improve uptime and the jaw gyratory crusher does this.
IM: Could you provide some information on the Gyromatic control system within these crushers?
How many companies are currently using this?
LB: The Gyromatic is our proprietary control device for our crushers, ensuring they run to the highest
performance and safety. It is installed in several operations worldwide.
IM: With the increasing number of block cave mines set to come onto the market in future years, do
you expect these jaw gyratory crushers to be in higher demand?
LB: Yes, we do; but we haven’t stopped there. We have gone to the next level and developed another
machine – the Eccentric Roll crusher (featuring a particularly flat and robust design, thyssenkrupp
says) – which we believe will lead the next generation of underground block caves due to its
extremely low height and high throughput.
thyssenkrupp
Industrial
Solutions’ jaw
gyratory crusher,
seen here at the
Northparkes mine,
was designed with
underground block
caving in mind
IM: How have these
primary gyratory
crushers evolved
since the first
installation at
Northparkes? Do
you expect to make
further adaptations
in the future?
LB: The overall machine has basically stayed the same. We have made improvements to parts, which
also cover our standard machine designs. We have also included a top service design, so we have
configurations that will suit all sites.
24 International Mining | APRIL 2020
The second generation of applications for CPF
involves tighter integration of the HydroFloat into
the concentrator flowsheet, according to Eriez.
“This tight integration means that the entire
plant becomes dependent on the performance and
operability of the HydroFloat, but many additional
benefits are unlocked,” Eriez explained. “In this
application, called Coarse Gangue Rejection
(CGR), the HydroFloat is situated in the milling
circuit and is used to develop a low-grade
concentrate and reject a fraction of the mill output
at a size between 200 and 700 microns.”
Later this year, in a paper at the Conference of
Metallurgists in Toronto, Canada, it will be shown
that a significant and measurable amount of
grinding energy can be eliminated, as well as the
size of the grinding mill, through such an
installation, Eriez said.
“Additionally, the amount of water can be
measurably reduced and the daily contribution of
fine tails to the impoundment can be decreased.
This is because coarse tailing sand is easy to
dewater and does not require impoundment in the
same fashion as fine tails.”
It can, for example, be used to raise the walls of
a dam rather than contribute to the volume inside
the dam.
Both the tail scavenging application and the
CPR configuration will be quantitatively evaluated
using ore from Capstone Mining’s Cozamin plant
in Zacatecas, Mexico, Eriez said, adding that the
objective at this site was to show the benefits of
both CPF options in the context of the same ore
type, geology and site.
Integrating ideas
While processes downstream of crushing and
grinding are helping the energy and water
balance, miners should also look at optimising the
upstream processes ahead of comminution.
Sophisticated simulation programs that study
the mine-to-mill process and the introduction of
‘digital twins’ will help the cause, as will drill and
blast software that assists planners with optimal
drilling patterns. Further digitalisation and
automation of processes will further aid this.
The introduction of more sophisticated ore
sorting solutions ahead of the most energy-
intensive processes could also improve the water
and energy balance.
In order to address these impending issues,
companies will need to take an integrated
solutions approach to this problem, studying all
parts of an operation and tailoring their solutions
to the orebody, company and location at hand.
Just as different parts of the mining community
are coming together to work on crushing and
grinding innovations, plant managers and drill and
blast engineers will need to collaborate more to
create the energy and water efficient mine sites all
stakeholders now demand. IM