Why is Ammoniacal nitrogen “difficult” to remove?
A. Ammoniacal nitrogen is not effectively removed by physical aerobic processes under normal conditions (processes which take place in the presence of oxygen), and therefore simple aeration without the presence of a sludge biomass, or spraying / irrigation is seldom very effective in its removal. An aerobic biological process is needed for ammoniacal nitrogen “removal”. When we refer to “removal” this normally comprises “nitrification” or the oxidation of NH4 to NO3 – itself a nutrient which may give rise to concern in an effluent.
