Calibration of Poorly Identifiable Systems: Application to Activated Sludge Model
Publication: Journal of Environmental Engineering
Volume 120, Issue 3
Abstract
The calibration of wastewater treatment models suffers from various ill‐definition problems, one of them being the difficulty in the identifiability associated with Monod‐type equations. The present paper presents a methodology for the calibration of such systems that, although not solving the identifiability problem, aims at locating it and finding a trajectory for circumventing its limitations. The procedure is a combination of the classical error‐function minimization with Monte Carlo simulations. The Monte Carlo technique assists in the selection of the optimal ranges of the parameters, and the optimization method focuses on the derivation of the optimal values of the parameters. The structure of the algorithm is such that it can also be applied in an autocalibration mode. The procedure was tested with data deterministically generated by the same model, and was able to converge to the “true” parameter values, which had been established a priori. The methodology was also utilized for the calibration of a larger model (11 parameters) with field data and the results obtained were superior to those from an error‐minimization algorithm conventionally applied.
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Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 120 • Issue 3 • May 1994
Pages: 625 - 644
Copyright
Copyright © 1994 American Society of Civil Engineers.
History
Received: Jul 21, 1992
Published online: May 1, 1994
Published in print: May 1994
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