A OPEN PIT MINING AÇIK OCAK MADENCİLİĞİ

of Mariana / Minas Gerais. This study
aimed to compare the operating costs, the
carbon dioxide emissions and the energy
consumption using three different types of
ore transport. The means of transportation
used in this comparison were: the traditional,
by trucks (Alternative 1), by the conveyer
system (Alternative 2) and the one with
mobile crushing (Alternative 3). In the
method that uses mobile crushing, once
fragmented, the ore goes to mobile
conveyors, configuring the in-pit, selfpropelled
system. As a result of research,
Lopes concluded that the use of fossil fuel
for transported ore was 3.25 and 2.06 times
higher in the alternatives 1 and 2,
respectively, in relation to the third
alternative. Concerning electricity
consumption a reduction of 77% and 12% in
the alternatives 1 and 2 is presented in
relation to Alternative 3. Regarding costs,
alternative 1 and 2 show 59% and 36%
higher costs respectively, compared to
alternative 3. Still, according to this author,
this type of self-propelled mobile crushing
has enough mobility to accompany the
movements of loading equipments in the
resumption to the ore pile. This equipment,
at the time of dismantling, gets out of the ore
launching range quickly, keeping the system
interconnected, allowing the quick return to
operation after dismantling. These
characteristics make this method more
efficient (Lopes, 2010).
A study presented by Schröder, also
proved that the method of in- pit mobile
crushing using conveyors has lower
operating cost than the traditional method by
trucks. The types of transportation studied
were the conventional method by trucks and
the In-Pit Crushing and Conveying. The
costs using IPCC showed a reduction of 64%
compared to the transportation by trucks
(Schröder, 2003).
Exploitation of a small limestone mining
in Austria, was possible only through the use
of the IPCC with glory hole. This system
consists in using a mobile crusher, a tunnel
that leads to the conveyor and a vertical
shaft that allows the removal of the ore.
Beyond economic issues, it is interesting to
highlight the recovery of energy generated
by the descending carrier. Thus the small
mining became self sufficient in energy
because that recovery is sufficient to keep
the whole system functioning. According to
Toshihiko Ohashi, despite being a small
operation, the project proved to be an
intelligent solution that could be applied in
large-scale in Brazilian mining, with good
results (Minérios e minerales, 2011).
Several companies around the world
invested and still invest in a system of in-pit
mobile crushing and subsequent transport by
belt (IPCC). Besides the reducing costs, the
use of this system has been highlighted for
being the method of transportation that less
degrades the environment.
Even though the mobile crushers and the
conveyor belts have been created some time
ago, only recently the IPCC has been used
more effectively. While reducing the
operational costs, its deployment requires
previous studies of mining exploitation and
its operation requires skilled manpower.
Vale, the largest Brazilian, and world's
second largest mining company is in the
process of licensing an iron ore mine located
in Serra Sul, Canaan dos Carajás - PA,
which promises to be the largest reserve of
hematite in the planet. The mine is planned
to produce up to 90 million tones of iron ore
per year. The project has been named S11D
and promises to be a reference in
sustainability. Unprecedented in iron mining
history, the transportation method will be
100% IPCC with use of self propelled
mobile crushers and mobile conveyors.
According to Goes, if the S11D mine was
operated by off-road trucks, it would be
necessary 100 huge trucks that would
consume 65 million liters of diesel per year.
With the mobile conveyors, the diesel
consumption will be of 15 million liters per
year, a savings of 77%. Only the auxiliary
equipments will continue consuming fuel.
The main equipment will be powered by
electricity. There will be carbon dioxide
reduction in identical percentage of diesel
and 174 large tires that are changed every
year in trucks will be saved. Highlighting
that, there will not be road building for the
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