The particularly efficient cleaning and classification of the feed
material by aqua vibrating separators is based on the combination
of differently acting processes in a single machine, superposed by
a vibrating motion.
The impurified sand fed to the aqua vibrating separator type ASS
at a normal grain size of 0-2 mm is homogenized in the prethickener
by adding water, thickened and then fed to the area of upward
current water. The grade of homogenization can be optimised by
the fresh water quantity added and by means of adjustable dis-
charge nozzles at the prethickener discharge. The excess water
is discharged via the overflow of the prethickener with sludge,
fine sand and low-gravity materials. The ASK type receives
coarse-grained materials directly from a chute.
From the prethickener resp. the chute the feed material enters the
troughed area of upward current water, sloping upward in the dir-
ection of transport of the material and being equipped with teeter
plates. These teeter plates and the vibrations of the machine trans-
form the feed material into a dense medium, whose density can be
varied by adjusting the upward current water quantity and -distri-
bution. In this jigging bed dense flow separation and sedimentation
take place, superposed by cross-current separation at the jigging
bed surface, which is generated by the water flowing off over the
rear wall against the direction of transport and the countercurrent
nozzles. Thus, the feed material is cleaned and low-gravity mat-
erials, impurities and fine sand are discharged over the rear wall.
The height of the rear wall is adjustable, i.e. the height of the jigg-
ing bed can be controlled and the discharge of fine sand can be
varied.
The area of upward current water is followed by a relaxation
zone, also sloping up in the direction of transport. This is where
the countercurrent nozzles are mounted above the jigging bed
and the purified feed material is settled. Further low-gravity mat-
erials and impurities are discharged with the help of a surface
current which flows towards the rear wall and which is gener-
ated by the countercurrent nozzles.
The relaxation zone is followed by a dewatering section resp.
a classifying section. In this area the upward slope of the machine
decreases considerably in the direction of transport. In the de-
watering zone the moisture content of the cleaned and classified
feed material is reduced to a specified value. The dewatering
section is interrupted by baffle plates. In the classifying section
the feed material is separated into different fractions depending
on the mesh width and the number of screen decks. The cleaned
and classified finished product is discharged at the end of the
dewatering resp. classifying section.
The vibration drive is a forced-synchronization twin-shaft unbal-
ance motor like that used in screen systems. Both linear and ellip-
tical or - in case of masses rotating in the same direction - circular
vibrations can be generated.
For influencing the process of feed material cleaning and
classifying, the following control options are available:
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