Nitrification in the Activated Sludge Process

There are two reduced forms of nitrogen that are of concern to wastewater treatment plant operators and state and federal regulatory agencies. These forms contain hydrogen and consist of nonionized ammonia or ammonia (NH3) and ionized ammonia or ammonium ion (NH4+). Although ammonia and ammonium ions are both present in wastewater, the amount of each is dependent on the pH of the wastewater. Keywords: nonionized ammonia; ionized ammonia; ammonium; wastewater