Does your cooling tower have a biofouling problem?
What’s growing in your tower? It’s important to be able to identify microbial biofouling in the industrial cooling systems that you treat. We know that biofouling is a bad thing … reducing the heat transfer performance of a cooling system, as well as causing microbially induced corrosion, harboring pathogens, and accumulating scale deposits. All these problems can lead to increased costs … and headaches for the water treater. But microbial biofouling, and its root cause, biofilm, may be hard to observe within the mostly hidden surfaces of a cooling system. A biofilm layer that is not even perceptible to the human eye can still significantly reduce heat transfer.
Dirty foam containing deposits in cooling tower basin released after successful biofilm control program treatment.
Being able to recognize the problem is critical to effective cleaning of a fouled system and maintenance of a cleaned system. So, when does a system need treatment, and if you have done a treatment, how do you know it was effective? Here are some common tests:
- Visual and tactile observations: colored or slippery slime deposits
- Diagnostics: Bacterial counts (plates, dipslides), indicating cultures (e.g., SRB), ATP, on-line biofilm monitors, deposit sample analysis by loss on ignition
- System performance: inefficient cooling, reduced heat transfer
- After a biofilm control program treatment, you should also see an increase in suspended solids, ATP, and bacterial counts in the bulk water as deposits are released. After removal of the released deposits by filtration or blowdown, repeated treatment should show decreasing evidence of biofouling.
AMSA’s BCP products, such as BCP 1015 (DTEA II), are penetrating aids, dispersants, and cleaners, that when used with a biocide provide an effective biofilm control program.
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