Separate treatment of the sludge digester liquors is an alternative for expansion of the mainstream treatment line. In order to reduce the oxygen demand for nitrification and organic carbon demand for denitrification, a shortcut in the nitrogen conversion pathway has been promoted in recent years, i.e. nitrification-denitrification via NO2-N instead of NO3-N. Although NO2-N is a common intermediate product of nitrification and denitrification, the mechanisms of NO2-N formation are complex with many competing and parallel conversions of production and consumption for this substrate. Therefore, the traditional approach to nitrification and denitrification modelling as one-step conversions is not acceptable anymore. This study aimed at investigating the effect of NO2-N on the kinetics of two-step nitrification-denitrification in the treatment of sludge digester liquors. First, two-step nitrification-denitrification rates were determined in the presence and absence of external NO2-N. Secondly, a mathematical model including two-step nitrification-denitrification processes was developed as an extension of the IWA (ASM2d) and implemented to estimate most important kinetic parameters for both processes (Henze et al., 2000).
Authors
Additional information
- Category
- Aktywność konferencyjna
- Type
- publikacja w wydawnictwie zbiorowym recenzowanym (także w materiałach konferencyjnych)
- Language
- angielski
- Publication year
- 2014
