Treahnent Plants for Nitrification
Nitrification
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Fig 6.20 Typical variation pattern for nitrification in traditional, low-rate biofilters, the Lundtofte wastewater treatment plant (Denmark).
The German recommendations are normally based on wastewater temperatures
above l2°C. At the loads mentioned, effluent concentrations of Cooo = 5 ± 40% and
CNH4= 1.5 ±50% can be achieved based on statistical distributions that are logarithmic.
Through the development of new types of filter media, full nitrification can be
achieved in traditional trickling filters, but for most practical purposes the process
is not economically competitive.
Biofilters for nitrification are often designed as rotating disc plants, as shown in Fig
6.21. The plants often consist of 4 ideally mix tanks in series, which is a good
approximation to a plant with plug flow. The organic matter is removed at the inlet
of the plant while ammonium is oxidized near the outlet.
Biofilters for nitrification can also be designed as submerged filters with aeration or
pure oxygen supply.
Fig 6.21 Rotating disc filter for nitrification of municipal wastewater.
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