Application of Anaerobic Digestion Model No. 1 for describing anaerobic digestion of grass, maize, green weed silage, and industrial glycerine

Anaerobic digestion of organic waste plays an important role for the development of sustainable energy supply based on renewable resources. For further process optimization of anaerobic digestion, biogas production with the commonly used substrates, grass, maize, and green weed silage, together with industrial glycerine, were analyzed by the Weender analysis/van Soest method, and a simulation study was performed, based on the International Water Association’s (IWA) Anaerobic Digestion Model No. 1 (ADM1). The simplex algorithm was applied to optimize kinetic constants for disintegration and hydrolysis steps for all examined substrates. Consequently, new parameters were determined for each evaluated substrate, tested against experimental cumulative biogas production results, and assessed against ADM1 default values for disintegration and hydrolysis kinetic constants, where the ADM1 values for mesophilic high rate and ADM1 values for solids were used. Results of the optimization lead to a precise prediction of the kinetics of anaerobic degradation of complex substrates.

► Four substrates were characterized by Weender/van Soest analysis.
► Anaerobic Digestion Model No. 1 was used to model biogas production.
► As an optimization method downhill simplex methods algorithm was applied.
► New kinetic constants indicated satisfactory correlation with experimental values.
► Applicability of the model for optimization of biogas power plants is confirmed.