Title: Microbial Induced corrosion in cooling systems and how regular monitoring can mitigate potential problems
We will investigate why having a large microbiological population in cooling systems is less than desirable and why regular monitoring can minimize the potential effects on the system.
While the effects of Biofilm in a system are well known, it is important to keep in mind:
o The very presence of the microbes prevents corrosion inhibitors from reaching and passivating the surface
o Corrosion reactions are accelerated by Microbiological interactions
o Microbial byproducts can be directly damaging to the metal
o The most common form of bacteria involved in MIC are Sulfate Reducing Bacteria (SRB’s)
Microbes, just like most lifeforms, have favorable conditions in which they thrive. Unfortunately, for water treaters, those favorable conditions are just what we find in cooling water systems and microbes are especially abundant in open recirculating systems due to the concentration of nutrients through cycling.
In cooling systems, the wet surfaces’ abundant growth of microbes leads to the formation of Biofilm which, if left untreated, can result in biofouling. This can lead to reduced plant life and reduced plant efficacy.
Biofouling issues need to be controlled, but their control depends on whether the microbes are in a planktonic or sessile form. The sessile form is responsible for Biofilm formation.
Once fouling has occurred in a system, even mechanical cleaning cannot remove all traces of the biofilm. Surfaces that have previously been fouled are more susceptible to colonization than new surfaces as residual biofilm materials promote growth and reduce lag time between fouling reappearing.
Catherine Allen is an Application Specialist and Product Manager at Tintometer Ltd, focused on products for use in the Industrial Water Treatment Market. Catherine is a graduate of Newcastle University having received a BSc hons degree in Applied Biology.
After graduation Catherine immediately started work as a Technical Specialist for a test kit manufacturer working in both laboratory and sales roles. Now, with over 21 years’ experience in water testing, Catherine is often consulted with for her knowledge about test kit and product design for Industrial Water testing applications.