Tennessee Wastewater Operator Practice Exam

What type of fouling can be reduced by high SRT treatment processes?

1. Chemical fouling

2. Physical fouling

3. Biological fouling

4. Thermal fouling

The correct answer is: Biological fouling

High SRT (Solid Retention Time) treatment processes are particularly effective in reducing biological fouling. This occurs because these processes allow for the growth and retention of a greater biomass of microorganisms that are specifically intended to degrade organic matter. In high SRT systems, such as those found in activated sludge processes, the environment supports the proliferation of bacteria and other microorganisms that can effectively consume nutrients and organic pollutants. This action helps prevent the accumulation of biomass on surfaces within treatment systems that can lead to biological fouling, which can negatively impact the efficiency of the wastewater treatment process. By maintaining a longer SRT, operators can enhance the stability and efficiency of the biological population, leading to improved treatment and reduced risk of biological fouling in tanks, membranes, or filtration systems. This focus on biological treatment contrasts with other types of fouling, such as chemical, physical, or thermal, where high SRT treatment processes might not have a direct impact.