Fuzzy approach for dynamic simulation of composting process under uncertainty

A methodology was developed based on fuzzy set theory to reflect uncertainties in the composting simulation modeling. The uncertain parameters under consideration include model parameters (such as the maximum specific growth rate, half velocity constants for degradable substrate and oxygen, and yield coefficient) and initial conditions (such as the initial biomass concentration, initial moisture content and initial temperature). The sensitivity analysis was used as an aid to simplify the calculation amount. A case of a composting process was presented to illustrate the effectiveness of the proposed method. The results show that the uncertainties in the model parameters and initial conditions will have significant impacts on the modeling outputs.