Total cost minimization control scheme for biological wastewater treatment process and its evaluation based on the COST benchmark process

Abstract

This paper proposes a new cost minimisation control scheme for a predenitrification type of biological wastewater treatment process and evaluates the validity of the control scheme based on the benchmark process presented by Copp. The control scheme adopting a hierarchical control structure incorporates lower-level controllers that consist of a set of local dynamic controllers and a higher-level static optimiser that provides the set points of the lower-level controllers based on the total cost index of Vanrolleghem and Gillot. Prior to benchmarking, this paper derives a simplified process model used for the optimiser, which is able to approximate the benchmark process model effectively as well as is simplified sufficiently for faster set point optimisation for on-line purposes. Numerical experiments evaluate the effectiveness of the proposed control scheme from various viewpoints including process operational and optimisation viewpoints.

Prioritize effluent quality, operational costs or global warming? – Using predictive control of wastewater aeration for flexible management of objectives in WRRFs

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Control en Estaciones Depuradoras de Aguas Residuales: Estado actual y perspectivas

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