Biofouling and Biocorrosion

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. Figure 1 shows 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..

Figure 1. Biofilm in stainless steel pipe.

Permissions
  1. Courtesy, N. Zelver

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 Figures 2, 3 and 4.

Figure 2. Nuclear power plant.

Permissions
  1. A. Cunningham, Center for Biofilm Engineering, Montana State University, Bozeman


Figure 3. Heat exchanger of the type used in the emergency cooling water systems of nuclear power plants.

Permissions
  1. A. Cunningham, Center for Biofilm Engineering, Montana State University, Bozeman

Figure 4. The same type of heat exchanger heavily fouled with biofilm and corrosion deposits. Such deposits can severely reduce the heat transfer capacity of heat exchangers thereby impacting the safe operation of emergency cooling water systems in power plants.

Permissions
  1. A. Cunningham, Center for Biofilm Engineering, Montana State University, Bozeman




















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:

It is obvious from this list of questions that the general concepts of biofilm detection, quantification and control are underlying themes.