JKMRC
PhD student Sanjeeva Latchireddi with a pilot scale version of
JK Jet Lift
A
Western Australian bauxite refinery has potentially saved $20
million with the installation of a Twin Chamber Pulp Lifter,
recently invented by a research student at the University of
Queensland's Julius Kruttschnitt Mineral Research Centre.
Sanjeeva
Latchireddi developed his invention as part of the
internationally renowned AMIRA/JKMRC P9 project, which attracts
substantial financial support from the mining industry.
One
of the project's sponsors, Alcoa World Alumina Australia,
approached the JKMRC to help solve a problem occurring inside
the semi-autogenous (SAG) mills used at their Wagerup refinery.
"The
restriction was being caused by the inefficiency of how the end
of the mill pumped the material out," JKMRC Comminution
Research Manager Dr Steve Morrell said. "Wheel type
apparatus at the mill's end - you could make the 'pump' work a
lot better."
Mr
Latchireddi's idea was to 'feather' this propeller which pushes
the slurry out.
"A
problem with the old pulp lifters is that as the slurry is
lifted up, not only does it slide out through the discharge, but
it can also slide back through the holes in the grate which it
first passed through, effectively 'short circuiting' the
process," Dr Morrell said.
"Sanjeeva
has angled the blades to keep slurry from going back through the
grate, which eliminated short circuiting."
After
extensive trials using an ANI pilot scale SAG mill at the
JKMRC's facilities in Brisbane, the new pulp lifter began to
take on the appearance of a turbine from a jet engine, leading
to its recent development and marketing as JKJetLift.
"Alcoa's
Wagerup refinery in Western Australia is the first operation in
the world with the new pulp lifter," Dr Morrell said.
Before
the new pulp lifters could be installed, Alcoa engineers had to
adapt the prototype's design to fit their commercial scale SAG
mill. Alcoa then fabricated the lifters and monitored mill
performance.
"Installation
of JKJetLift at Wagerup has increased throughput by 15 per cent
from 390 tonnes an hour to 450 tonnes an hour, which is regarded
as a massive increase by industry standards."
He
said the installation has been so successful that Alcoa may not
need to install another mill at Wagerup as planned for the next
expansion, effectively reducing the capital required from
$30million plus to around $10million.
Alcoa
Technology Development Group Senior Chemical Engineer Mr Denis
Nicoli said the design and manufacture of the Twin Chamber Pulp
Lifter (JKJetLift) is one of the mineral processing industry's
most significant advances in recent years.
"The
new pulp lifter has alleviated congestion in the mill, allowing
us to look at increasing throughput by raising the mill's speed
and increasing ball charge," he said.
"These
options were not previously available due to the restriction
placed on the mill by the old pulp lifter."
