Reduction of the Anaerobic Digestion Model No1 for an industrial wastewater treatment plant by principal component analysis

The Anaerobic Digestion Model N°1 (ADM1) is accepted widely as a common platform for anaerobic process modelling and simulation. However, this model has an excessive complexity and a large number of parameters and states. This hinders its calibration and its use in control applications, and may render it inadequate for development of state observers. Therefore, a technique of model reduction for biological models based in principal component analysis was applied to identifying a new reduced stoichiometric matrix. The method shows that the main model features can be obtained with 2 reactions. Then, the kinetic parameters have been estimated on the base of representative known biological kinetics (Haldane or Monod). The reduced developed model takes into account the measured states in anaerobic wastewater treatment plants and captures the good qualitative behaviour of the ADM1. The reduced model accurately reproduces the dynamics of the process.