Kinetic study of compost liquor nitrification
This study is a first kinetic approach about the compost liquor treatment by activated sludge. This industrial wastewater is highly loaded in organic and nitrogen compounds (COD≈12,000 mg L(-1) and NH(4)(+)-N≈4,000 mg L(-1)). The possibility of its treatment in an urban WWTP is studied measuring ammonia oxidation rate with non-acclimated sludge to the industrial effluent. Compost liquor appears as an inhibitor substrate. The ammonia oxidation rate can be modelled by the Haldane model: U(MAX)=0.180 d(-1), K(S)=12.0 mgN.L(-1) and K(I)=26.0 mgN.L(-1). The ammonia oxidation rate also follows for a synthetic substrate which has the same pollutant load as the real substrate. In this case, the ammonia oxidation rate can be modelled by the Monod model: U(MAX)=0.073 d(-1) and K(S)=4.3 mgN.L(-1). This result confirms that the ammonia oxidising bacteria are inhibited by the real wastewater. The following-up of nitrate production shows also the inhibition of nitrite oxidising bacteria. The compost liquor treatment seems not possible in an urban WWTP (<50,000 p.e.). That's why a specific WWTP is recommended and an acclimation step of activated sludge is essential.
Jérémy Gagnaire, X. Y. Wang, L. Chapon, Philippe Moulin, Benoît Marrot. Kinetic study of compost liquor nitrification. Water Science and Technology, 2011, 63 (5), pp.868-876. ⟨10.2166/wst.2011.263⟩. ⟨hal-01026430⟩
Journal: Water Science and Technology
Date de publication: 01-01-2011