Many liquids and solids can be divided using the force
of gravity. This process can be accelerated using a centrifuge.The
centrifuge separates solids from liquids using centrifugal
forces many times greater than the force of gravity. This
separation effect occurs in just the same way as it would
in a settling tank but in the case of the centrifuge the
tank is in the form of a stainless steel bowl that is
spun at high speed. The settled solids accumulate at the
bowl wall and are then discharged by means of a helicoidally
shaped screw known as a scroll, which pushes the solids
from the cylindrical section of the bowl, up through the
conical section and towards the discharge ports. The liquid
phase, known as the centrate, finds its way back down
the centrifuge bowl where it flows out over a “weir
plate”, as it would in a lagoon, and falling by
gravity down the discharge pipe.
The process of separating the liquid from the solid matter
is sometimes called dewatering.
Sewage sludge dewatering
Dewatering of paper mill sludges
Clarification of vegetable processing liquors
Applications in petrochemicals
IWE's rotary thickener is used for the thickening of
industrial and municipal sludges with the use of polyelectrolyte.
Its main function is to thicken sludge from 0.3 to 4%
up to 6 to 8% dry solids, thereby reducing sludge volumes
From the integral mixer the machine receives treated sludge
onto the internal surface of a wedgwire drum. The rotating
action of the drum causes the free water to pass through
the wedgewire whilst trapping the solids on the surface
of the drum.
Continual rotation forces the solids to the discharge
end causing further dewatering of the sludge. The thickened
sludge is discharged to a hopper from where it is pumped
SAS sludge thickening
Primary sludge thickening
Potable water sludge (Ferric)
Centrifuge Filters for Abrasives
WE's abrasive centrifuge filters have been designed to
handle separation duties where the abrasive nature of
the solids makes it impossible for either decanter centrifuges
or disc stack separators to be considered. They provide
a solution to industrial solid liquid separation for a
wide range of applications.
The centrifuge has a vertically mounted bowl rotating
at high speed. The mixture of abrasive solids and the
liquid is fed into the machine where the heavy phase,
the abrasive solids, are forced to the bowl wall by centrifugal
force while the liquid phase, the centrate, is collected.
The solids accumulate at the bowl wall where they build
up and discharged at pre set intervals. This is a fully
automated process allowing the centrifuge to operate continuously
without operator intervention.
Any mixture that will settle out into a heavy and a light
phase under normal gravity can be considered for treatment
. These machines produce between 1000 and 2000 G and since
the solids stay static at the wall of the bowl there is
The applications for the AS range are:-
Treating Cooling Liquids from Grinding or Polishing
Wastewaters from processes using glass bead or powders.
Waste Oil Cleaning
Sludge dewatering of small sludge volumes.
IWE can provide separation equipment installations on
a “turnkey” basis designing complete systems
or processes and working closely with our customers. We
are also able to operate under our project management
and control. Since we have expert knowledge of all our
technologies, and considerable process knowledge, we know
how these can be combined to achieve optimal performance
from the process.