Modeling of turboflo - a novel biofilm reactor for wastewater treatment

A mathematical model of a novel industrial-scale biofilm reactor - TURBOFLO - was developed. The reactor is an internal circulating airlift with rectangular cross-section. High density polyethylene granules with a density of less than 1 g/cm3 were used to support bacterial growth. The reactor was used for several months for nitrification of secondary effluent. The mathematical model consisted of three differential mass balance equations for ammonia, dissolved oxygen (DO) and biomass. Description of gas-liquid mass transfer was the critical part of the model. The most successful approach was based on Higbie's penetration theory and Kolmogorov's isotropic turbulence.