[Effect of Filter Speed and Water Quality on Ammonia Removal in Groundwater Containing Iron, Manganese, and Ammonia at Low Temperature].

and successfully started. In this process, when the water inlet concentration remained the same, the improved filter speed would reduce the efficiency of ammonia nitrogen capture by the filter column, increase the concentration of ammonia nitrogen in the depth of the filter layer, and improve the efficiency of ammonia nitrogen ions capture by anaerobic ammonia oxidation bacteria (AnAOB) in the depth of the filter layer, so that the ammonia nitrogen removed by CANON in the water increased, while the ammonia nitrogen removed by nitrification decreased. When the filter speed remained unchanged, the concentration of ammonia nitrogen in water was increased to make the ammonia nitrogen with higher concentration enter the filter layer, which increased the concentration of ammonia nitrogen in the zone where ammonia nitrogen and nitrous nitrogen coexist, and improved the net catching efficiency of AnAOB on ammonia nitrogen ions in the filter layer, thus resulting in an increase in ammonia nitrogen removed by CANON.