Enhancement of anaerobic digestion digital twin through aerobic simulation and kinetic optimization for co-digestion scenarios

An upgraded digital twin of the Anaerobic Digestion Model 1 is proposed to enhance its industrial applicability and range of use. Through the optimization and generalization of kinetic coefficients toward co-digestion reactors simulation and insertion of new equations for the complete biokinetics modeling of H2S, the proposed model can predict more precisely the exiting biogas fractions comprehensive of H2S and O2 without any parametric adjustment. Moreover, it is proposed a new function representing the oxygen-methanogens. The model has been validated through the comparison with other literature models and with experimental data coming both from the literature and from an industrial plant. The comparisons show its flexibility and industrial applicability. Finally, an optimization of the methane content through oxygen rate adjustment is proposed, increasing CH4 content of 4%vol. The mathematical model has been built using Python™, which makes it easily spreadable and usable.