Robust interval-based SISO regulation under maximum uncertainty conditions in an anaerobic digester

A robust regulation law is proposed for the stabilization of an anaerobic digester for the treatment of organic wastewater. This process exhibits a highly nonlinear dynamic behavior with poorly known parameters. In addition, it must work under an uncertain environment with the presence of unknown inputs. Supporting some structural and operational conditions, this regulation law exponentially stabilizes the regulated variable around its nominal value in the presence of uncertainty and input disturbances. Experimental results are presented using a 1 m/sup 3/ continuous fixed bed anaerobic bioreactor used for the treatment of industrial wine distillery wastewater.