IMPORTANCE OF MICROBIOLOGY TO COOLING
WATER SYSTEMS
Microorganisms cause fouling
Fouling leads to deposition and scaling
Microorganisms also cause corrosion
Reduced heat transfer and corrosion damage costs big $
1
PRIMARY BIOFOULING
MICROORGANISMS.
Algae
Fungi
Bacteria
3
4
Life forms in Cooling
Water System.
10
0
pH
Typical Range
Extended Range
Optimum Range 2
4
6
8
12
Bacteria Fungi Filamentous Algae
Unicellular Algae
pH range for microorganisms
BIOFILM DEVELOPMENT
Biofilm development:
Adsorption/Absorption of organic molecules on surface.
Transport of microorganisms from the water to the solid surface.
Adhesion of microorganisms at surface-water interface.
Replication of attached cells Production of exo-polymers Detachment of newly formed biofilm by flowing
water.
Repeated process of biofilm formation elsewhere