VIBRATING MILLS
Operating
principle:
The material passes
the cylinder along a helical
path with
transportation being primarily a result of
displacement. Due
to the effect of vibration, the
material is
directed to the outlet. The grinding
cylinders which
perform almost circular move-
ments by the effect
of unbalanced weights, are
filled with
grinding media to 65 vol.%.
In general,
reduction by impact forces is
predominant in the
Palla mill. Possible grinding
cylinder
connections as shown hereunder
Particle
sizes and throughputs:
Feed size : from
1 to 25mm
Final fineness:
100 to 2mm by direct
grinding
- and 30 - 100 -
in closed circle with
sieving machine or
air classifier
Throughputs: from
100kg/h up to .
25t/h (depends on
the product to be grinded)
Advantages
:
· reduced
space requirements
· low
energy consumption
· reduced
installation costs; direct installation on factory soil
possible
· especially
interesting in case of explosive products, because
filling grade
grinding medias + product is about 95 vol. %
· easy
adjustment of the amplitude (up to 12 mm)
· wear
minimised, impact grinding
· possibility
of iron-free grinding by using ceramic
grinding media and
inner liner
· reduced
and easy maintenance,
bearings are
fastened in the webs in such a manner that the
complete
unbalanced-type drive can be easily removed.
· grinding
media only need to be refilled
· excellent
homogenizing of the product
· no
air production, consequently no need of a filter
(cost reduction)
· direct
cardan drive
FIELDS OF APPLICATION
AUBEMA Vibrating Mills are used for grinding
of almost all materials in the processing industry,
from medium-sized lumps up to finest grains. The
particular fields of application are coal, chemicals,
ceramics and pit and quarry industries, including
their subgroups.
FEED MATERIALS
Lignite, hard coal, ash, coke, charcoal, dolomite,
marble, silica sand, limestone, bentonite, lime,
gypsum, puzzolan, bauxite, copper granules, iron
oxide, ferrosilicon, magnesium oxide, arsenide,
aluminium oxide, silicon carbonate, zirconium,
fireclay, corundum and similar products.
Twin-
Tower Mills:
As tumbling mills such as ball and rod mills are not very
effective in fine grinding due to due to their loe power intensity,
alternatives for fine and ultra fine grinding are tower mills and stirred
mills. In contrast to tumbling mills where motion is imparted to the charge via
the rotational mill shell, in tower and stirred mills motion is imparted to the
charge by the movement of internal strirrer while the shells are stationary.
Construction:
In a tower mill steel balls or pebbles are placed in a vertical
grinding chamber in which an internal screw flight provides medium agitation.
The feed enters at the top, with mill water, and is reduced in size by
attribution and abrassion as it falls, the finely ground particles being
carried upwards by pumped liquid and overflowing to a classifier. Over sized
particles are returned to the bottom of the chamber, and the final
classification is by hydrocyclones, which returned underflow to the mill sump
for further grinding.
Advantages:
Its instalation area is small
Its noise level is low
Its energy usage is efficient
It shows minimal overgrinding
its capital and operating cost is low
Capacity:
Its capacity is 100t/h with the product size of 1-100 micrometers
It can grinde a variety of material like limestone, silica, rock
salt, coal and copper concentrates