WWTP’S BIOLOGICAL PROCESS SIMULATION: CONVENTIONAL ACTIVATED SLUDGE COMPARED WITH MEMBRANE BIOREACTORS

Abstract

Since the introduction of ASM1 in 1987 by  the working group of the International Water Association (IWA), modeling of biological processes in Wastewater Treatment Plants (WWTP) has evolved exponentially in the last decades. Since 2007, more than thousand papers referring to ASM models have been published. Several software tools have been developed during the last twenty-five years to assist researchers and operators in interpreting results and model outputs. The contribution of modeling to the development of environmental decision support systems (EDSS) has been applied to a much larger extent in northern European countries than in Italy. As a matter of fact, models, if correctly calibrated and validated for specific cases, can provide valuable help in building scenarios that can give indications on the effects of introducing new processes or technologies for upgrading existing plants, or of different operational strategies aimed at reducing energy consumption. The study deals with the calibration and validation of modeling a biological process in an existing WWTP (average flowrate: 55,000 m³d^-1 in dry weather) and it has been used to simulate the upgrade of the plants with MBRs. Results confirm operational data taken from a recently built MBR plant.