WORLD NEWS
Limestone mining without drilling or blasting
The use of Wirtgen surface miners significantly reduces noise and dust emissions as well as ground vibrations.
Wirtgen surface miners play a
key role in increasing production
and reducing costs in material
extraction for a large cement
plant in Ukraine.
PJSC Ivano-Frankivskcement
(IFCEM) produces clinker and
300 other cement and gypsum
products. The raw material for
the cement plant comes from
a deposit located 15km to the
north. The Carpathian mining area
is rich in sedimentary rocks such
as limestone, marl, and gypsum.
For years, the material was
extracted by drilling and blasting
and then wet-processed into
clinker in the cement plant. In a
move to increase productivity and
reduce costs, IFCEM became the
first cement plant in the Ukraine
to initiate the transition from the
wet to the dry process.
The dry process is now
considered the preferred method
for clinker production, as it
reduces fuel consumption per
ton of material. This in turn has
a positive effect on production,
costs, and the environment. For
an optimal drying process, the
material from the quarry should
only have a low moisture content
so that it can be crushed in a dry
crusher, ground to powder in the
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JANUARY 2019
raw mill, and burnt in the rotary
kiln without further pre-treatment.
To ensure that the material
extracted from the quarry is
as dry as possible, a radical
change in the mining method
was necessary. Meanwhile,
the previous use of explosives
for limestone mining was
having a detrimental effect on
neighbouring residential areas
due to the noise generated and
the ground vibrations. IFCEM
found the solution in Wirtgen
surface miner technology.
By gradually phasing out the
drilling and blasting operations,
the surface miners progressively
reduced the time and cost
involved in pre-crushing and post-
crushing the material and also
made it possible to redesign the
deposit. By ensuring a defined
slope of the surface with the
aid of the Level Pro automatic
levelling system, the surface
miners created the conditions for
efficient dewatering.
Compared to drilling and
blasting, this allows much drier
raw material to be mined and
the material can enter the plant’s
drying process without any
further treatment. Thanks to the
redesign of the mining area with
the surface miner, the exploitation
of the deposits has also been
increased, because now even
previously unused areas can be
worked and additional material
extracted.
Together, three Wirtgen surface
miners generate a daily output of
7 000 tons, which also leads to
optimum utilisation of the
cement plant.
The 2500 SM, which can
remove material up to 650mm
deep, extracts the material in
Ivano-Frankivsk up to a depth
of 40–45cm. Depending on
the rock hardness, the surface
miner achieves a feed rate of
5m per minute and a grain size
of 0–100mm. Depending on the
hardness of the rock, the entire
tooling is replaced at intervals
that vary between 200 and 500
hours based on the machine’s
field of application.
Since its market launch,
the 2500 SM has proven its
performance and flexibility
worldwide, as it can be used
for the selective mining of
raw materials with uniaxial
compressive strength up to
80MPa and in special cases even
higher. The surface miner cuts,
crushes, and loads the rock in
a single operation. Depending
on the application, the material
can either be loaded directly
into trucks via the 11.3m-long
slewing discharge conveyor of the
miner, deposited laterally or as a
windrow between the machine’s
crawler tracks.
According to Yaroslav
Nesterovych Voznyak, technical
manager of the deposit, the
surface miners, especially the
2500 SM, have had a positive
influence on the production cycle
in the quarry and thus also in the
cement plant: “The purchase of
the Wirtgen surface miners made
the transition from drilling and
blasting to a safe mining process
easy to implement. In addition
to the environmental and
production benefits, the surface
miners have proven to be the
best solution, especially in terms
of cost efficiency and economical
operation. The grain size of the
material produced is ideal for
the cement plant. This is why
our fleet of surface miners will
grow. We are already preparing
a further mining area with a
volume of around 180 million
tons of material, which we want
to mine with our Wirtgen surface
miners.”
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