Study of the U.S. Institute for the Environment Introduction to Water and Wastewater and Treatment Tuesday July 14, 2009

Typical WWTP

WWTP Schematic

Primary Settling A = ammonia N = nitrate = organic matter = solid matter = pathogen = bacteria = nitrifying bacteria

Primary Settling Tanks at Johnson County Wastewater, Tomahawk Station View of the water surface beneath the cover for a primary settling tank. Johnson County Wastewater, Tomahawk Station

Biological Treatment A = ammonia N = nitrate = organic matter = solid matter = pathogen = bacteria = nitrifying bacteria

Close-up of a wastewater distributor for a Trickling Filter Biological Treatment System. Johnson County Wastewater, Tomahawk Station.

Final Settling Tank at Johnson County Wastewater, Tomahawk Station Secondary Settling A = ammonia N = nitrate = organic matter = solid matter = pathogen = bacteria = nitrifying bacteria

Final Settling Tank at Johnson County Wastewater, Tomahawk Station

Disinfection A = ammonia N = nitrate = organic matter = solid matter = pathogen = bacteria = nitrifying bacteria

Chlorine disinfection contact basin at Johnson County Wastewater, Tomahawk Station

Sludge Treatment

Anaerobic or aerobic digestors ~16,600 municipal wastewater treatment plants in the US ~1,006 have anaerobic digestion Fewer than 19% of those utilize biogas for heat or power.