Treating the liquid fraction of pig slurry in a sequencing batch reactor by nitrification-denitrification: model calibration

Abstract

The availability of a calibrated model for a particular system makes it possible to accurately predict its behavior and, therefore, the design and/or performance optimization. Ammonium rich wastewaters such as the liquid fraction of pig slurry were considered for treatment through nitrification-denitrification in a lab-scale sequencing batch reactor (SBR). Specific calibration assays, mainly conducted using respirometric techniques, enabled the estimation of compositional, kinetic and stoichiometric parameters included in a mathematical model focused on biological nitrogen removal. Heterotrophic biomass showed high capability for organic substrates storage prior to degradation. Furthermore, the presence of biodegradable organic substrates for a complete denitrification was identified as the main limiting factor of the treatment, even when processing raw waste.