Know that air flow through a natural
draft cooling tower is due largely to the
difference in density between the cool
inlet air and the warm exit air. The air
leaving the stack is lighter than ambient
air, and a draft is created by chimney
effect without the need of mechanical
fans.
Spray ponds cool by evaporative cooling
so it occupies less area compared to
cooling ponds. A spray pond uses a
number of nozzles that distribute water
into contact with the available air in the
surrounding.
Sufficient distance between the spray
nozzle and the basin should be provided
to keep the spray nozzle and the basin
should be provided to keep the spray
from being carried over to the sides of the
pond basin.
46
PECM Issue 30
C ooling T ower M aintenance
Cooling tower maintenance requirement
is no doubt very minimal. The following
are essentially the basics to be carried out.
1.
Electric Fan Motor: Where draft
is provided by fan mechanism
the motor bearings need to be
greased regularly of
prevent noise while the belts are
checked for broken and loose
ones.
2.
Transfer Pumps: The same
maintenance requirements
applicable to all pumps are
applied and have been
discussed earlier under pumps.
3.
Louver Fence: Loose ends are
to be replaced to contain all
water and to prevent
water loss. In some
designs louvers are
formed with woods whereas in
others of metal plates.
In any case always check the
interlocks bolts tightened any
loose ends.
4.
Distribution Nozzles: Nozzles
could be blocked and will cause
uneven water spray
or distribution across
the tower, which may
result to tower inefficiency.
Good distribution is
very necessary. Blocked
nozzles could result
from fouling effect due
to deposits of scales
formed by minerals
salt available in the
water. Blocked nozzles
should be freed.