PRODUCT
SHOWCASE
Innovative
sand dewatering system introduced
The
new Aggre-Dry FMW screen from GreyStone combines a fine material screw
and dewatering screen to produce sand and gravel products with a moisture
content as low as 8-13 per cent, by weight, while using only 30 hp
to wash and dewater up to 90 tonnes/h.
The Aggre-Dry system utilizes a standard
GreyStone inclined single-spiral fine material washer to initially
dewater the material. At the same time, the rotation of the dewater
screw scrubs the material to help remove surface dirt. The action
of the screw flights sends the sand up the inclined tub, thus ensuring
the that the dewatering screen located at the top of the flights will
be evenly fed. The vibratory dewatering screw further removes moisture
from the sand. This combined process produces a caked, dry sand product
that, according to the manufacturer, neither an inclined dewatering
screw nor a vibratory screen can separately achieve. The GreyStone
dewatering screen, curved around the spiral flights on the Aggre-Dry
FMW screen, has several unique features. A 0.25 mm screen opening
reduces the amount of material that can fall through the screen. The
feed from the screw allows material to build to a bed depth of 355
mm on the screen, squeezing additional moisture from the sand as the
vibratory motors move it along the length of the screen cloth, further
reducing the moisture content.
In what GreyStone describes as the Aggre-Dry’s
most innovative feature, the unit re-introduces the throughs from
the screen back into the screw’s washing process, where the
screw portion of the unit again pushes it to the units’s dewatering
screen, increasing the amount of saleable product.
This process is claimed to eliminate
the need for separate pumps and cyclone sand separator machinery –
along with the additional horsepower to run this extra equipment.
GreyStone also states the Aggre-Dry FMW screen should use less than
half the horsepower required to process the same tonnage of spec product
on a traditional screen/cyclone system. In addition, the manufacturer
has increased the water handling capacity of the units for more versatility.
As production of these units increases,
Aggre-Dry models will be offered in all of GreyStone’s stand
fine material washer sizes, from 914 mm x 8.54 m to 2133 mm x 11.6
m.
www.greystoneinc.com
Track-mounted screening
plant has four-way product split
Extec
has introduced its S-7 triple-deck Doublescreen that has been developed
for aggregate producers who require large throughput, mobility, and
four clean gradings.
The heart of the S-7 is the triple deck
Doublescreen Box. According to the manufacturer, this enables the
screener to incorporate such independent features as: screen-box slope;
screen-box vibration; screen-box amplitude and screen-box speed.
The advanced triple-deck Doublescreen
box of the S-7 allows for individual changes to the drive, angling,
vibration and meshes of each screen box. Thus, states the manufacturer,
the S-7 is able to provide a maximum level of separation on most materials,
at very high rates of production.
The screen boxes possess the same features as found on the S-Series,
but the S-7 has the added capability of being able to adjust the amplitude
of the box depending on what type of screening is required. This
can be changed on either of the two boxes providing the option
to run the primary at a higher amplitude to the secondary, or vice
versa.
The S-7 possesses extended stockpiling
conveyors, with faster running belts, to enable greater productivity.
In order to support the longer conveyors, and cope with increased
production demands, the S-7 utilises a purpose built chassis designed
around the 4-way split design.
www.extecscreens.com
Fine
material washing system uses new technology
The
TYCAN Hydro-Clean from W.S.Tyler is described as a new, innovative
solution to washing technology. The Hydro-Clean removes silt and clay
particles as small as 63 microns from mineral mixtures. The maximum
particle size of the feed material can range from 0 up to 150 mm.
The “dirty material” is fed to a washing drum where high-pressure
nozzles rotate at 60 rpm and spray the material with water at pressures
of up to 2900 psi. The water streams are injected into areas of the
rock (i.e. holes, cracks etc.) that are difficult to reach with traditional
cleaning technologies such as log washers or screws. The end result
is claimed to be a much cleaner product that generates significantly
higher values.
In many cases, the Hydro-Clean allows
aggregate producers to turn waste material, which incurs dumping costs,
into sellable material. According to the manufacturer, overall operating
and structural costs are lower than with traditional washing systems,
given the compact size and weight. The Hydro-Clean is also environmentally
friendly thanks to it extremely low water consumption and low power
usage. The Hydro-Clean is available in four model sizes, capable
of producing 20 to 400 tonnes/h depending on the application.
www.wstyler.com
Idler
rolls have moxie
Superior
Industries has developed an idler roll its claims will last three
times longer than steel while significantly cutting operating costs.
Designed with a specially formulated high density polyethylene (HDPE)
material, Moxie™ rolls have been developed to solve such problems
as uneven wear and belt misalignment caused by abrasive material and
buildup. The manufacturer describes new idler rolls as a quiet, lightweight
alternative to steel that can be retrofit into any idler frame or
bracket.
Moxie rolls are manufactured with Superior’s
SpinGuard seal system that protects against contaminants getting to
the bearing. Combined with the HDPE material, Moxie rolls are said
to produce a low roll resistance that translates into reduced horsepower
requirements.
www.superior-ind.com
November-December
2007 Issue
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