AIB 015
100% Barmac Sand for Brazilian
Dam Project
Throughout the world, concrete producers are moving
towards the use of crusher fines – traditionally a waste
product– as manufactured sand products. Increasingly
extensive testing is showing that manufactured sand can
be used to make concrete with superior strength
characteristics and at a lower cost than concrete made
with natural sand
Case Study
A Brazilian operator was designing a crushing plant
to produce manufactured sand for one of the largest
dam operations in Brazil. 100% manufactured sand
was to be used for the construction and therefore the
products had to be of the highest quality. There were
two major factors which influenced their choice of
crushing technology; the material and the product
specifications.
Major Benefits To The Concrete Industry
In today's competitive aggregate market, many plants
are faced with fluctuating demands for different types
of sand and aggregate product, with increasingly
stringent specifications being imposed.
The Barmac B-Series VSI uses a unique rock-on-rock
crushing process. This crushing action grinds and mills
the feed material to produce a high quality,
equidimensional product with no contamination from
wear parts. As the material fed into the Barmac grinds
and impacts against itself, the typical cost per tonne
of material processed is very low.
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The material is a basalt, which, due to its cleavage
planes, is easily crushed in the initial stages, however,
in the later stages, it tends to be very resistant and
difficult to fragment. In addition to this,
specifications dictate that fines below 80 microns
shall not exceed 15%.
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The Solution
Initially, the installation consisted of two primary
jaw crushers, three secondary cones and a Barmac VSI
crusher in the tertiary alongside a cone crusher. At
this stage, the Barmac generated 60% of the plant's
sand production of 180 tph.
Following pilot tests, it was decided to increase the
plant sand capacity to 200 tph by installing a
quaternary Barmac VSI.
Barmac B6900 VSI
110kW [150 hp]
Feed: –25 +4.75mm
Product: –4.75mm
Production rate: 113 tph
(excluding coarser aggregate products)
100
90
Barmac Prod
80
Other Benefits and Advantages
70
Cum % Passing
The installation of the second Barmac increased the
capacity of the plant by 20 tph with minimal changes
to the existing plant.
Barmac Models Selected
Barmac B9600 VSI
440kW [600 hp]
Material: Basalt
Throughput: 330 tph
Feed –25 +4.75mm
Product: –4.75mm
60
50
40
30
Conclusion
The Barmac crushers were fundamental to this plant’s
ability to produce manufactured sand with the specified
gradation and shape characteristics. In addition to this,
the Barmacs allowed the plant to not only meet but
exceed the design capacity, contributing to the
completion of the dam forty days ahead of schedule.
Further Business
The success of the B9600 and the B6900 in this project
led the operator to purchase yet another B6900 to
further increase the capacity of the plant.
20
10
0
0.01
0.1
1
Sieve Size (mm.)
10
100
Please Note: This is the product grading obtained from the B9600
Barmac crusher.
Barmac VSI crushers are also used in the industrial minerals,
mining, recycling and general quarrying industries. A wide
range of materials are processed through Barmac crushers
worldwide. For more information on this or any other Barmac
application, please contact your nearest Barmac
representative.
Cone Crusher
Jaw
Crusher
36” x 45”
3 x 2 Deck Screens
Cut 1 = 50mm [2”]
Cut 2 = 25mm [1”]
–50 +25mm Product
3 x 2 Deck Screens
Cut 1 = 9.5mm [3/8”]
Cut 2 = 4.75mm [3/16”]
2 x Cone Crushers
Minus 4.75mm [3/16”]
–9.5 = 4.75mm
[–3/8” = 3/16”]
Aggregate
Cone Crusher
Barmac B6900
110kW [150 hp]
Barmac B9600
440kW [600 hp]
Metso Minerals (Matamata) Limited
Mangawhero Road, Private Bag 4071,
Matamata, New Zealand
Tel. +64 7 881 9060, fax +64 7 888 5244
[email protected]
AIB 015 – 1 – 4/99