A generalized model for aerobic granule-based sequencing batch reactor. 1. Model development

A generalized model was established for simulating an aerobic granule-based sequencing batch reactor (SBR) with considerations of biological processes, reactor hydrodynamics, mass transfer, and diffusion. Methodology of discretization was effectively used for the model development and calculations. The activated sludge model no. 1 was modified to describe the biological processes within the granules. Based on the difference between the calculated and measured results, the model structure was further improved through introducing simultaneous consumption of soluble substrates by storage and heterotrophs growth with a changeable reaction rate. Model calculations were conducted using a MATLAB program. The calculation results show the respective contributions of granules in different size fractions and slices to the overall change of model component concentrations. Moreover, oxygen concentration profiles within granules and oxygen consumption rate varied in one operating cycle. This confirms the applicability and validity of the discretization method and the model structure.