PRODUCT FOCUS
thyssenkrupp’s various crushing equipment solutions include stationary crushing plants, semi-mobile crushers that can be moved to a new location as
the mine expands, and finally, fully mobile options.
equipment for the first step in the process, where equipment combinations exist, mobile crushers that can be moved
namely material excavation at the pit face. such as trucks feeding shiftable and to a new location as the mine
Hydraulic excavators are recommended extendable conveyors, coupled with expands and finally, fully mobile
for selective coal excavation and compact fixed overland conveyors to handle the options. The fully mobile crushing
mining applications, while the higher longer distances. plant travels behind the excavator
production efficiencies offered by bucket
wheel excavators make them the preferred
choice for continuous block mining in
larger mines. Next comes the choice of
transport systems required to move the
excavated material to run-of-mine (ROM)
crushing stations.
Steyn notes that mine life determines
transport system decisions. While
shiftable and extendable conveyors
significantly reduce operating costs, they
are less flexible than trucks and costlier.
Mobile conveyors are ideal where more
flexibility is required, but the capital
costs are higher. For large operations
and long-distance materials handling,
Upon reaching the crushing stations,
excavator and only then onto a truck
by feeders at a controlled flow for or transport conveyor, the need for
processing. Best feeder unit choice double handling is eliminated.
depends on material composition and Stockpiles are normally required
required throughput. The thyssenkrupp between the mine and the port, and
feeder range includes reciprocating the selection of suitable stockyard
plate or push feeders (ideal for equipment (stackers and reclaimers)
large lump sizes and low capacities);
rotary plough feeders; grizzly screens
(best suited to higher capacities but
unsuitable for sticky material); and apron
feeders (controlled and continuous
feed at high capacities and suitable
for feeding very large lumps). “We
also supply a wobbler feeder, which,
like the grizzly, combines feeding and
is closely associated with the specific
purpose of the stockpile. Big storage,
small buffer stocks and/or blending will
determine the stockyard type, which
includes longitudinal, cone, kidney,
circular, and bunker. “Again, it is best to
start at the ship-loading process, where
consideration of port storage facilities,
product grades or types, reclamation
fixed overland conveyors provide the screening, but it can handle sticky, moist best solution in terms of both capital material such as coal at medium to high rates required to load the ships, and
and operating costs, but limited capacities,” adds Steyn. delivery requirements for material
from the mine will determine preferred
flexibility is the compromise.
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and, as it is loaded directly from the
the material is fed into the crushers In some mining applications such Extensive solution offering as continuous block mining, there is a thyssenkrupp’s various crushing good balance between flexibility, high equipment solutions include select the reclaimer before considering
production, and low operational costs stationary crushing plants, semi- the stacker and stacking method. “In
FEBRUARY 2019
equipment,” advises Steyn.
He further recommends to first
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