10. AMBIENT COOLING WATER POND
The simplest and most reliable and affordable cooling method
to use in tropical, sub-tropical
or moderately temperate climates, is either a natural earth
pond or otherwise to use an
inexpensive "Hydrex" wire-mesh heavy duty plastic lined
irrigation pond. For continuous
working in a sub-tropical climate, the tank should have a
capacity of 400 litres cooling water
per Nm3/h gas cooled. In cold winter climates the water can
also be pumped from the nonfreezing
+4 degrees C water layer between the top ice and the bottom
of a dam, river or lake.
In order to prevent freezing, the cooling water pipes must
be buried in the ground and in the
water to frost free depth.
In a tropical or sub-tropical climate it is, because of the
absence of toxic compounds in the
cooling water, necessary to chlorinate the water in order to
prevent the growth of algae and
mosquito larvae. An ordinary cheap “inhibited chlorine”
floating swimming pool chlorine
tablet basket should be used. Ordinary un-inhibited chlorine
must never be used since this
could cause severe damage. If the plant is running
continuously, chlorinating is not necessary.
As an alternative cooling method, the cooling could be done
by using a space saving SJG
vacuum water fan cooler having its own vacuum water
balancing tank, with provision for
removing most of the dust and in cold climates also any
water condensates, before these enter
the reduced cooling water stream.
The gas scrubbing/cooling water, if let directly through the
scrubber on a one use only basis,
would contain less than 30 parts of solids per million of
mainly lampblack carbon and fine
silica particles with some traces of iron, manganese, zinc
The scrubbing water, both after being recycled for 18 months
and also from "one-use-only"
water, has been tested by the environmental water analysts
"ERGOSAF" in order to determine the toxicity and any traces
of tar, as well as the solids content. It was found that
there are no traces of tar and that the water is non-toxic.
The suspended solids are also low, as the sludge
continuously sinks to the bottom of the cooling pond. The
re-cycled scrubbing water can, according to the “ERGOSAF”
test report, be let out over the ground without causing any
harm to the environment.