Wastewater New York State Practice Exam

Pathogenic organisms can be removed from wastewater treatment processes by which method?

1. Centrifugation

2. Filtration

3. Both centrifugation and filtration

4. All of the above

The correct answer is: All of the above

Pathogenic organisms can indeed be removed from wastewater treatment processes through various methods, which include both centrifugation and filtration, as well as other techniques. Centrifugation is a mechanical process that employs centrifugal force to separate particles from liquids. In the context of wastewater treatment, this method can effectively concentrate and separate suspended solids, including pathogenic microorganisms, from the liquid phase by spinning the wastewater at high speeds. The denser solids, which may contain pathogens, settle at the bottom, allowing for their removal. Filtration, on the other hand, is a physical separation process where wastewater is passed through a filter medium that captures particles based on size. This process can be particularly effective in removing larger organisms and suspended solids, including debris that may harbor pathogenic organisms. The type of filter used can influence the size of the pathogens that are retained, allowing for varying degrees of removal efficiency based on the filtration method employed. Both methods are complementary in wastewater treatment systems, often used in tandem or as part of a multi-barrier approach to effectively reduce the number of pathogenic organisms in treated water. Additionally, other methods, such as disinfection, may also be incorporated to ensure further pathogen removal, contributing to the overall effectiveness of wastewater treatment processes in public health protection