20-01-2012, 04:24 PM
OK vertical roller mill
OK_Vertical_Roller_Mill.pdf (Size: 763.67 KB / Downloads: 65)
Operating advantages
The rollers are in a lifted position when
the mill is started, ensuring trouble-free
start-up. This eliminates the need for an
auxiliary drive. A control system monitors
the machinery and facilitates operation.
Mill design for versatile applications, simple operation and long life
Mill arrangement
This schematic illustrates a typical
grinding installation. The arrangement
is very simple and the operation is
correspondingly flexible and reliable.
To maintain the appropriate temperature
in the mill circuit – for example to
ensure adequate dehydration of the
gypsum when grinding cement – the
layout is prepared with provisions for
recirculation of hot exit gas to the mill
inlet. In case the mill feed is wet slag
or includes a significant portion of wet
additives, additional heat must be provided,
for instance from a heat generator.
Otherwise, if the mill feed is very
hot, the mill exit temperature controls
a damper for cold air intake.
Nozzle ring bypass system
For slag grinding, a specially designed
nozzle ring bypass allows the iron
particles to segregate through nozzles
without airflow and subsequently be
removed by a magnetic separator to
minimise wear of the mill internals.
One mill, many products
The OK mill efficiently grinds blended
cements, with a wide range of additives
such as slag, puzzolana, limestone and
fly ash. Its versatility is demonstrated
by the ability to switch between a
wide variety of mixes, and to vary the
particle size to meet individual needs.