DEAMMONIFIKATION SOM EN NY PROCESS FÖR BEHANDLING AVAVLOPPSSTRÖMMAR MED HÖG KVÄVEHALT / Deammonification as a new process for treatment of wastewater with a high nitrogen content
Pilot plant-scale experiments have been carried out to study a new technology for nitrogen removal from digester supernatant. The plant comprises two parallel lines, which now operate as a two-step process. Two pilot plant reactors (each volume of 2 m3) were filled with Kaldnes rings up to 50 % of their volume. In the First step of the process, half of the ammonium is oxidized to nitrite without further oxidation to nitrate (nitritation). Then the second step follows, where equal amounts of ammonium and nitrite reacts to form nitrogen gas (Anammox). The pilot plant is continuously fed with supernatant from digested sludge dewatering process at the Himmerfjärden WWTP. This type of wastewater has a high ammonium concentration and a low content of biodegradable organic matter.