Coal mill is major equipment of cement plant and used for drying
and grinding coal. The equipment is mainly consisted of feed
device, main bearings, rotating parts, drive device, selling
device, high-voltage start-up device and lubrication system. The
raw material is fed into mill by feeding equipment. The hot wind
enters into the mill by inlet end. As the mill cylinder rotates,
the coal and hot air exchange heat in the mill. The coal is crushed
and grinded in the mill. When the coal is being grinded, the powder
is brought out of the mill by the hot air going through the
mill. The coal mill we make is with reasonable
structure, high grinding efficiency and is the ideal equipment for
coal processing.
Make the safe operation
of coal mill :
Improper operation of the coal mill may cause the explosion of the
machine . What is the proper method to operate coal mill to avoid
the disaster?
1. change the piling method of the coal to make the coal accumulate
little ; thus avoid the spontaneous combustion of the coal
.
2. change the gap of the grate bar from *5mm to *2mm; thus decrease
the wind speed and increase the drying speed .
3. add a settling chamber between the coal mill and the pipe; thus
prevent the hot coal powder enter the coal mill
.
4. add a explosion-proof valve at the opening .
5. increase the fineness of the coal from *0% to *5%
.
6. make up strict safety rules .
If the coal mill stops for 3 days, empty the coal hopper or put a
layer of raw meat powder on the surface to isolate the coal from
the oxygen before stopping the coal mill, close the hot wind valve
and open the close wind valve and then stop the feeding. remember
to empty the coal in the coal mill before stopping the machine and
not to stop the collector immediately .
Check the following things when operating the coal mill: the airing
is ok; there is no overfeeding or underfeeding; the temperature is
not too high; the order of starting and stopping the coal mill is
right; the temperature of the air from the coal mill is higher the
dew point.
Make an emergency plan; when an explosion happens, close the hot
wind valve and the pneumatic valve, prevent the hot coal powder
enter the collector and if the temperature is over *0 degree
centigrade, start the carbon dioxide extinguisher. we should pay
attention to avoid safety problem in operating the coal mill. as
long as we obey the safety rules, the safety problems surely can be
avoided.
