Modeling secondary clarifiers
Dynamic modeling of the biological processes for water treatment

Soluble and insoluble elements follow different paths (figure 5 ): soluble matter (S) is characterized by hydraulic residence time, while particulate matter (X) follows the residence time of solids, known as "sludge age" (determined by extraction rate and liquid/solid separation efficiency).

The clarifier (secondary clarifier) simultaneously clarifies the effluent and concentrates the sludge prior to recirculation and extraction. Theoretically, it has no influence on soluble compounds, but operates a liquid/solid separation: particulate compounds are retained and concentrated at the base...