A mathematical model with time-varying parameters was developed to des
cribe the dynamic behavior of the anaerobic mesophilic digestion of an
imal waste. Batch and continuous cases were considered. In the case of
continuous process linearized models were proposed. Special emphasis
was given to the parameters identification. Using sensitivity analysis
and optimization software a simple methodology was developed. The mod
el verification and validation were made with different sets of labora
tory experimental data. Simulated results were in good agreement with
experimental data under different operating strategies. The model prop
osed in this paper (with its linearized and with reduced order modific
ations) can be used for process control. Copyright (C) 1996 Elsevier S
cience Ltd.