DYNAMIC MODELING OF SUBSTRATE DEGRADATION IN SEQUENCING BATCH ANAEROBIC REACTORS (SBAR)

A dynamic model was developed for sequencing batch anaerobic reactors (SBARs) to describe substrate degradation under non-steady-state conditions. Assuming unionized volatile fatty acids were inhibitory, simulation results showed that product inhibition of methanogenesis and substrate degradation in the SBAR process can be expressed by modified Haldane or non-competitive inhibition functions. The proposed modified functions also reflect quite accurately the effect of large variations in reactor biomass concentration as a result of dilution during the fill stage. The determination of kinetic parameters and the verification of the model were made with different sets of experimental data. Simulated results from the model were in good agreement with experimental data under different operating strategies.