Your Cooling
Tower May Have a Yeast Infection:
Okay....picture this....
There you are on shift one day, minding your own business, probably reading your favorite
tech manual ("The wonderful World of Emissions Control") ,when out of
nowhere, you hear a sound not unlike the wail your mother-in-law-to-be made upon
discovering that her only daughter had decided that a life with you would be far
more rewarding than with any ole' neurosurgeon.
Immediately, you rush from the control room, dropping "The Wonderful World of
Emissions Control" and the copy of "Sports Illustrated" which
was hidden behind it (Now how did THAT get there?).
To your dismay, you find your main feed water pump smoking from holes that, oddly enough,
you failed to notice on your last set of log readings.
Yes boys and girls! This is what happens if we allow biological growth to occur in our
cooling towers!
"Huh?" is your clever retort. "What do a few microbes and fungus have to do
with my feed pump spontaneously self destructing?
Professor Overdrive will tell you in one word....."Heat Transfer!"
Okay...that was two words.
The point is this: Heat transfer in your cooling tower can be adversely affected by the
growth of "Micro-Biologics".
That Bearing and shaft seal cooler attached to your recently deceased feed pump gets its
cooling water from your tower system. If heat transfer is adversely affected by
microbiological growth, less heat is removed from the cooling water. Pretty soon, your
bearing and seal cooling water gets too hot to cool much of anything. It does not take
long for your feed pump bearings to get very hot. Your bearings do not like to get very
hot. Eventually your bearings do not want to play anymore. They take their balls and go
home. Your feed pump soon misses his friends and their balls. He gets sad...he goes boom!
All of this because of a few blue-green algae.
Micro-biologics just love cooling water. It is warm, wet and open to air, much like your
swimming pool at home.
Remember when you first got your pool? You found friends you never knew you had? Remember
how they seemed to multiply before your very eyes? This is similar to the dilemma in your
cooling tower.
Just think of the people in your pool as algae...or better yet...fungi. See how they sorta
cling to the side? Notice how they block the filter?
Time to add some chlorine.....
Yes...it may be that simple actually. Then again it may not. Chlorine (or Bromide) while
inexpensive, is also corrosive to many metals which may be present in your cooling tower
system (it is classified as an "oxidizing" biocide: oxidation causes corrosion).
It will also not kill all forms of organic life in your system water.
It is usually necessary to coordinate your program with a second "non-oxidizing"
biocide to effectively combat those little buggers. The next time your chemical rep drops
by to deliver the doughnuts (or bagels...or whatever it is he uses to bribe you into
believing he is better than the other guy), ask him what program is best suited for your
tower system based on size and type of metals. A properly coordinated biocide program
coupled with effective corrosion inhibitors, will ensure your cooling tower's heat
transfer surfaces are clean and in good shape.
So...as you sit there, huddled over the remains of your feed pump, remember your
friend...the biocide. By understanding the dynamics of microbiological growth in your
cooling tower water, you will be better equipped the next time you hear the battle
cry..."There is a Fungus among us!"
