the nitrified wastewater. Mixing in the anaerobic denitrification reaction vessel
may be accomplished using low-speed paddles analogous to standard flocculation
equipment. Flotation clarification follows the denitrification step with the floated
sludge being either returned to the head end of the denitrification system or
Fig. 3.22 An attached-growth trickling filter system uses primary flotation clarification and
secondary flotation clarification
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