Biofouling and Biocorrosion

Let us begin with the category of biofouling and biocorrosion in industrial water systems. Industrial water systems typically have copiotrophic??? (nutrient-rich) water which is circulated at ambient temperatures which are often favorable of rapid microbial growth. These conditions can result in large biofilm deposits forming along the flow path as shown in Figure 1.

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Courtesy, N. Zelver

Figure 1. Biofilm in stainless steel pipe

Thick biofilm in a small diameter stainless steel pipe. Biofilm was grown under turbulent flow conditions in a nutrient-rich, recirculating system at 20 degrees C.

This type of large-scale biofouling is common in many industrial water system components including, pulp and paper manufacturing, cooling towers, and nuclear power plant circulation systems. An example of biofouling and biocorrosion in nuclear power plant heat exchangers is shown in Figure 2.

Concerns:

CBE’s experience with industrial biofouling problems can be summarized by listing the most frequently asked questions from industrial practitioners interested in biofouling and biocorrosion. These questions include:

• What environmental conditions promote biofouling?
• Where (in a particular industrial water system) is biofouling likely to occur?
• How do biofilms influence corrosion?
• What are strategies for controlling biofilm accumulation and biocorrosion?