Amcot ST Series - Page 46

AMCOT ST SERIES FIBERGLASS COOLING TOWER
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GENERAL MAINTENANCE & CONTROL
Water Treatment
Blowdown/Bleed
As a cooling tower is in operation, your system is constantly evaporating water at a rate of
approximately 1% of the circulating water every minute. This is a natural occurrence in the heat
removal process.
When this evaporation occurs, the water is removed from your system, but any solids (suspended or
dissolved) in the circulating water system remain. As a result, these solids steadily increase in
concentration and even with a water treatment program in place, these values will increase to the point
that the dissolved solids will precipitate (meaning they will go from a dissolved state to a solid) and
cause scale formation on the tower.
The only way to remove these solids from your system is to establish a bleed or blowdown value.
Bleed/Blowdown is where you will remove a small volume of circulating water continuously from your
system which will help lower the overall concentration to minimize precipitation. You water treatment
specialist will be able to evaluate your water analysis and establish what the proper rate should be when
they set up your chemical system.
Non-Chemical Treatment
Non-Chemical water treatment systems have become increasingly popular and many have been
successful when properly maintained and serviced. Non-Chemical systems can be used as a substitute
over chemical feed systems. It is important to note however, that they are not maintenance free. So
you will need to still have monthly servicing for these types of systems. You will also still need to
establish and maintain a bleed/blowdown rate on your cooling tower. These systems typically will have
a higher initial cost, but long term cost is expected to be greatly reduced because you do not require
chemicals.
Solids Filtration
Chemical and Non-Chemical treatment programs help with dissolved or suspended solids and biological
organisms (when biocide is added), however they cannot take care of actual particulates or debris such
as dirt, silica, sand, or other solids that could enter your system. For these foreign particulates it is
important that you never operate the tower without the suction strainer in place.
Solids filtration can be provided by incorporating basket strainers into your piping layout, or through the
use of separators or sand filters.
Amcot offers solids filtration systems and inline strainers should you seek to incorporate these into your
system. For more information, contact Amcot or your manufacturer’s representative, and we will be
happy to assist you.