INDUSTRY EQUIPMENT: MINING
equipment’. However, once the capital cost
of the stacker has been recovered, the
life of mine cost diminishes substantially.
For one, the maintenance on stackers is
minimal, they can continue working 24/7
for the life of mine and longer, and the cost
of consumables is negligible compared
to ‘yellow equipment’. Then we are not
even taking into consideration the operator
costs along with labour- related concerns
or the safety and environmental benefits of
using automated stackers,” says Steyn.
thyssenkrupp stackers are custom designed and can weigh more than 300 tonnes.
But, costs aside, the importance of
blending material into homogenous
stockpiles, should probably override
cost considerations in any continuous
processing plant. To build a homogenous
stockpile to feed into a processing plant or
heap blended material consistently with
front end loaders or trucks, is extremely
difficult, if not impossible. Steyn says
stacking is critical for reclaiming and
achieving a proper blend. “If a mine or
quarry has to feed the processing plant
with fairly homogenous raw material, or
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if they export a specific grade of material
and the grade from the pit is inconsistent
and they have to blend different material to
ensure a homogenous stockpile, the first
critical stage in the process is stacking,”
Steyn explains.
As the material enters a plant, it needs
to be stacked in such a way that it can be
reclaimed efficiently and in order to achieve
a homogenous blend if required. “One of
the most important factors of blending
material is how it is stacked in the first
place,” Steyn emphasises. “If you do not
stack material properly, you will always
struggle to achieve decent blending and or
reclaim rates,” he adds.
In mining and quarrying operations
stackers are used to stockpile Run of
Mine (ROM) material so that it can be
reclaimed again for processing, and for
stockpiling different products once the
ROM has been processed. It is also used
to load trains and trucks. In ports and
harbours, product is brought in by trains
or trucks and stockpiled before being
reclaimed and loaded onto ships. Power
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