ABC®-N Denitrifi cation System The ABC®-N (Anoxic Biofi lter Clarifi er - Nitrogen) denitrifi cation device is designed primarily for removing nitrite/nitrate-nitrogen from wastewater. The ABC®-N, typically installed after a FAST® (Fixed Activated Sludge Treatment) or any other nitrifying biological system, is used when the nitrogen reduction provided by a normal biological system is not enough to meet very low total nitrogen standards. With the addition of a carbon source, the ABC®-N promotes the growth of bacteria that will denitrify nitrifi ed wastewater from most residential or commercial wastewater fl ows. The denitrifi cation process is the conversion of nitrites and nitrates to nitrogen gas through a special biological process. The ABC®-N performs the denitrifi cation process by utilizing an anoxic environment, whereas there is no dissolved oxygen (no blower system for this zone) and the presence of oxidized nitrogen (provided from the FAST® or nitrifying biological system), carbon source (supplied by a separate manufacturer), and anaerobic bacteria to convert nitrite and nitrates into nitrogen gas. The anoxic conditions must exist for the denitrifi cation process to take place. This process will help lower the total nitrogen in the effl uent. The ABC®-N’s unique combination of a recirculation header and pump thoroughly mixes the nitrifi ed wastewater and supplemental carbon throughout the fi xed fi lm media. In addition, the mixing device provides a suffi cient scouring velocity for the removal of any excessive growth on the media. Much like the well-proven FAST® technology, a properly sized ABC®-N allows solids to settle to the bottom of the containment tank for occasional removal. Better Water. Better World.® ABC-N ® DENITIRIFICATION DEVICE