AFRICA NEWS
Guinea: bauxite mining facilitated with rapid transportation
West African Guinea is known for
possessing the largest reserves of
high-quality bauxite in the world. This
potential has prompted the country
to continually expand its bauxite
mining sector in recent years, making
substantial investments. Wirtgen
surface miners are playing a decisive
role in this development process, as
many of the country’s bauxite mining
operations rely on Wirtgen’s technology
as their standard extraction technique.
Wirtgen supplies surface miners in a
variety of performance classes for the
selective mining of raw materials, such
as coal, limestone, bauxite, gypsum,
salt, and phosphate. In addition to
mining, these machines can also
carry out routing operations for the
construction of mining service roads
and railway tracks, the rehabilitation
of roadways, and installation of tunnel
floors. The range of applications further
includes the precise cutting of trenches
and channels as well as surface
levelling.
In 2001, the first Wirtgen surface
miner was commissioned in a mine
close to Kindia, a small town 120km
from the capital, Conakry. At this
time, drilling and blasting was the
main bauxite mining technique in use.
Since then, however, the process has
shifted to the more economical, safe,
and environmentally friendly surface
mining, and today Wirtgen surface
miners extract 100% of the ore. Since
2001, the Wirtgen technology has
proven its additional benefit to the
growing bauxite mining industry in
Guinea, where 25 Wirtgen machines
are currently in operation.
2200 SM and 2500 SM for
consistently high production rates
During the mining process, Wirtgen machines produce level surfaces that serve as
stable roadways, facilitating rapid transportation of the mined material.
6
APRIL 2019
The most commonly used models
for bauxite mining in Guinea are the
2200 SM and the 2500 SM. The
first is compact yet powerful, with a
2.2m-long cutting drum and 708kW
of engine power. It is able to cut
rock with unconfined compressive
strengths of up to 50MPa, ideal for
medium-sized mining operations.
The larger model, the 2500 SM,
guarantees higher production rates
and offers a cutting width of 2.5m,
783kW of engine power, and can
economically mine rock with an
unconfined compressive strength of
up to 80MPa.
Both models demonstrate their
advantages in both productivity and
product quality, guaranteeing lower
production costs per ton compared to
conventional mining. On average, 1.25
million tons of bauxite are extracted
each year with the 2200 SM and three
million tons with the 2500 SM. These
figures are achieved because the
machines work 24/7.
The figures are all the more
impressive considering Guinea’s humid
climate, with a monsoon season
that lasts from June to November,
which is a major challenge for
mining companies. During periods
of heavy rainfall, cutting-to-ground
or drilling and blasting expose the
ore to precipitation, resulting in high
transportation costs due to the ore’s
high moisture content resulting in
other negative downstream effects.
Wirtgen surface miners, which are
equipped with a discharge conveyor,
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