Damköhler Number Design Method to Avoid Plugging of Tidal Flow Constructed Wetlands by Heterotrophic Biofilms
نویسندگان
چکیده
Clogging of subsurface flow (SSF) treatment wetlands due to excess biofilm growth is a design problem for which only empirical guidelines exist. A method is proposed to systematically analyze this type of clogging as a design tool. In recognition of the physical reality that most SSF treatment wetland processes are a function of biofilm surface area, a Damköhler number (Da) definition based on specific surface area is used to investigate a method of predicting clogging induced by heterotrophic biofilms growing on treatment media. This method entails estimation of aggregate surface area and modeling of biofilm growth, and is developed in a tidal flow (flood and drain) pilot SSF wetland. The results are then applied to a horizontal flow SSF wetland. Results suggest that Da values can be used to predict biofilm clogging in SSF wetlands.
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