Keywords: activated sludge-biofilm reactors, hybrid reactors, model, multistage, in-series, effluent quality profile, wastewater treatment, biofilm, mathematical modelling, activated sludge, kinetic parameters
Design of multistage activated sludge-biofilm reactors: a rational approach
This paper outlines a mathematical model developed for steady-state multistage completely mixed hybrid reactors, starting from basic mass balance expressions for the system and Fick's theory for diffusion of substrate into the biofilm. The model being complex, a design procedure has been proposed that uses predefined effluent quality profile across the system and results in an accurate and optimum design of the system for a desired degree of treatment. Using reported values of kinetic parameters from literature, it has been concluded that the proposed computationally efficient procedure can be successfully used for the design and control of these reactors.