ABSTRACT
In studies of waste treatment, waste characterization can be regarded as one of the most important tasks because the waste composition and concentrations greatly affect the process behaviors. This paper proposes a waste characterization method for anaerobic digestion based on ADM1. The relationships between the steady state of the process and the concentrations of the influent components are investigated and determined based on the use of information regarding the process output to estimate the waste characteristics. In addition, a new procedure of parameter division and optimization for characterizing the influent waste is proposed. Here, the parameters to be estimated are divided based on the bi-linear nature of the problem, identifiability and information content of the parameters, under the given measurements. Parameter division can greatly reduce the search space for optimization problem and can ensure that the estimate is minimally sensitive to the selection of initial parameter values. The proposed method is tested through a case study of the pilot-scale anaerobic digester and through a numerical simulation. Simulation results show that the waste characteristics estimated using the proposed method best fit the critical states of the process although some parameters are difficult to identify. In addition, it is proved that the parameter division can find the maximal number of parameters which are identifiable from the given measurements and can improve the estimation accuracy.