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andprocessed the scrapmaterials to export
size for shipment toAsia tobe recycled.
Liberty Industrial’s resourceful and
innovative approach towastemanagement
and environmental stewardship significantly
minimised the amount ofwastedisposed in
landfill. 108,000 tonnes (97%) of the site’s
111,000 tonnes ofwastewas recycledwith
only3,000 tonnes of allwaste going to landfill.
In addition to the 7,000 tonnes of plant and
equipment items salvaged and12,000 tonnes
of scrapmetal recycled, Liberty Industrial
found resourceful solutions todisposeof
25,000 tonnes of concrete andwasteproducts
from theHismelt process, including50,000
tonnes of slagwaste, 7,500 tonnes of dolomite
and5,000 tonnes of large irons skulls,
sourcingbuyers andprocessingmaterials
to their specifications and consulting
geotechnical engineers andblending fill
materials;
Liberty sourced a local buyer for the 25,000
tonnes of concretewhowas looking for a
supplyof roadbaseover a fourmonthperiod.
The concretewas pulverised to remove 1,500
tonnes of reinforcing so that crushing could
bedonequickly and efficiently. In addition,
50,000 tonneof slagwaste from theHIsmelt
processwas crushed into14mm roadbase
and stone, and sold for reuse. Abuyerwas
also sourced for the 5,000 tonnes of large iron
skulls that containedupwards of 70% iron
and thematerialwas processeddown to4 to
5 tonneblocks so that it couldbe loadedonto
abulk scrap ship and shipped toVietnam for
recycling.
In lieuof disposingof the 7,500 tonne
of dolomite offsite, Liberty consulted
geotechnical engineers about its suitability
as fillmaterial.Once a suitableblendof fill
materials hadbeendetermined, thedolomite
DEMOLITION AWARDS
was incorporated and reused across the site as
backfill.
Balancing the conflicting interests of key
stakeholderswho come to theprojectwith
different expectations and interestswas
critical to the success of theHismelt project.
With two clients to satisfy, Liberty Industrial
managed the keyobjectives of the twoon the
project;Molong’s keydriverwas the timely
executionof theprojectwhileRioTinto’s key
prioritywas compliancewith stringent safety
and environmental standards.
Liberty achieved ahigh level of client
satisfaction through value adding andhigh
standards of service anddelivered this project
in accordancewithRioTinto’sworld class
standards and compliance requirements
for themanagement of health, safety,
environment andqualityperformance.
Liberty Industrialwas able to realise
maximum value from anumber of reusable
plant, process equipment and scrapmaterials
anddeliver a cashpositiveproject outcome
forRioTinto through efficient demolition,
and innovative asset recovery and resources
recovery solutions. Theplant closureproject
delivered forRioTintowas cashpositiveby
approximately$3.5 (€2.8)million. In addition,
Liberty Industrial alsodeliveredoptimal
project outcomes forMolong. The ground-
breakingdismantling and salvage operation
was a complete success; deliveredwithin
budget, on schedule, without incident and in
accordancewith their exacting specifications.
The specialist expertise and experience
of Liberty Industrial’s personnel together
with state-of-the-art demolition simulation
technology ensured a safe and sustainable
outcome; Liberty Industrial successfully
completed115,000manhours ofworkon
theprojectwithout a single lost time injury,
recyclingover 108,000 tonnes ofmaterial.
■
TheExtremeLoading softwarewas used
to3D simulate the induced collapsemethods
to ensure that the companywas satisfiedwith
themodeof failure, pre-failure structural
stability and the effects ofwindon the
weakened structure.Modelling the structure
and simulating theproposeddemolition
methodology allowedLiberty to refine its
methodology anddemonstrate a successful,
safe and controlledoutcome to risk averse
clientRioTintowell in advanceof executing
the task. Through this simulationLiberty
was able to test its proposeddemolition
scenario involving initial weakening followed
bypullingusing cables and todetermine
thepulling force required to collapse the
structure. The applicationof this innovative
technologywas akey factor inmitigating
andmanaging thepotential risks associated
with the task, ensuring the structurewas
demolished in a safe and controlledmanner.
Once thehigher structureswere at
ground level thedemolitionof theplant and
infrastructurewas undertakenbyLiberty’s
heavyduty customised230 tonneLiebherr
994 (Australia’s largest demolition excavator).
Thismachinewas assistedby a 120 tonne
Hitachi, two46 tonne and five 36 tonneVolvo
excavators, two semi tippers, two telehandlers,
a 40 tonnedump truck, water truck, service
truck and various sizedboom lifts.
Various structures, including theoff gas
hood, smelt reduction vessel and the lock
hopper, were collapsedusing controlled cut
andpull demolition techniqueswhereby
engineeredpre-cutting and inertia is utilised
tobring taller structures toground level.
Working in combinationwith a smaller
fleet of excavators equippedwith shear
attachments, the 230 and120 tonne excavators
pulled the structures apart. The remaining
structureswere systematicallydemolished
and thematerials processed. Excavatorswith
various demolition attachments downsized
Liberty’s Liebherr 994
atwork on the site
AHitachi EX1200 atwork processingmetal scrap
ready for shipment and recycling
