Model Based Evaluation of the Sequencing Batch Airlift Granular Sludge Reactor for Simultaneous COD, N- And PRemoval

Aerobic granular sludge system is a novel technology which offers a possibility to design compact wastewater treatment plants based on simultaneous COD, nitrogen and phosphate removal in one sequencing batch reactor. A mathematical model was developed to describe the structure of the microbial community evolving in the multi-layered architecture of aerobic suspended granular sludge biofilms. The model described the experimental data from this complex system sufficiently. Sensitivities of process parameters on the nutrient removal rates could therefore be reliably evaluated. The predicted spatial distribution of phosphorus accumulating organisms and nitrifiers inside the granules by the model, are in good agreement with the experimental study results of the distribution of the microorganisms inside the granules by Fluorescent In Situ Hybridisation (FISH) technique. The influence of the oxygen concentration on nitrogen removal was analyzed and the optimum oxygen concentration predicted to be 40% by the model.

Keywords:

Wastewater , Aerobic granulation , Mathematical modeling , P removal , N removal