Mine excursion
Mapi Mobwano, general manager at Sishen, in the
pit during Mining Mirror’s site visit.
times, improved grade control with
the use of a modular system and
GPS technology on the shovels, and
increased shovel productivity.
Controlling the fleet
“The fleet management system can
really be compared with an aircraft
control system, which ‘tells’ aircraft
where to land, when to land, and to
make sure they don’t crash into each
other,” says McGavigan.
This is exactly what Dispatch
does. At any given time, there are
98 haul trucks, numerous secondary
equipment, and more than 20 shovels
in the Sishen pit. For Mobwano,
it is important that the equipment
operates as quickly, efficiently, and
safely as possible, and to time the
mining sequence to a tee, in order
to increase productivity and reduce
costs. The Dispatch system controls
the mining operation and has brought
many benefits. For one, the average
speed of the haul trucks has increased
from 21km per hour to 29km per
hour. This is not, however, purely
[14] MINING MIRROR AUGUST 2018
because of the Dispatch system. The
haul roads, for example, are all in an
impeccable condition. It is watered
down regularly, and although Mining
Mirror visited Sishen on a windless
day, there was not a sign of dust. The
mine’s roads are managed by dust
suppression experts Dust-a-Side,
and monitored by environmental
company I-Cat. In 2016, Sishen
implemented a safety project called
LDV–HDV separation, which means
that on 70% of the roads to and in
the pit, light-duty vehicles drive next
to the main haul roads used by the
heavy-duty vehicles. Moreover, all
vehicles and equipment are fitted with
proximity detection systems.
“To increase the speed of haul
trucks by 7km per hour or 8km per
hour doesn’t sound significant, but if
it is applied to all 98 trucks for 365
days a year, it makes a big difference,”
says McGavigan.
In addition to the abovementioned
technology projects, McGavigan
says that smart devices to monitor
and control the processing of ore
in the plant, have resulted in more
noteworthy benefits. “At Kolomela,
we have cameras on the conveyor belts
and monitoring equipment on the
crushers, which means we can adjust
our crushers in real time. As a result,
the mine can improve its lumpy to
fines ratio,” explains McGavigan. This
technology will soon be deployed at
Sishen as well.
Lumpy ores are Sishen’s premium
product. The mine produces four
different products: premium lump,
20mm premium lump, standard lump,
and standard fines. In 2015, Sishen
constructed a modular ultra-high
dense medium separation (UH DMS)
plant to complement its existing
DMS and JIG plants. The plant is
being expanded now. It was added
with the intention to capture JIG
discards, which previously ended up
on the plant discard dump as waste.
The material is now being converted
into a saleable product. The modular
plant consists of conveyors, cyclones,
a densification circuit, an ore circuit,
and a water circuit.