Experimental design for evaluating WWTP data by linear mass balances. (1st October 2018)

• Record Type: Journal Article
• Authors: Le, Quan H.; Verheijen, Peter J.T.; van Loosdrecht, Mark C.M.; Volcke, Eveline I.P.
• Is Part Of: Water research. Volume 142(2018)
• Page Start: 415
• Page End: 425
• Publication Date: 2018-10-01
• Subjects: Experimental design -- Data validation -- Mass balances -- Data reconciliation -- Wastewater treatment plant; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2018.05.026
• Languages: English
• ISSNs: 0043-1354

Abstract

Abstract: A stepwise experimental design procedure to obtain reliable data from wastewater treatment plants (WWTPs) was developed. The proposed procedure aims at determining sets of additional measurements (besides available ones) that guarantee the identifiability of key process variables, which means that their value can be calculated from other, measured variables, based on available constraints in the form of linear mass balances. Among all solutions, i.e. all possible sets of additional measurements allowing the identifiability of all key process variables, the optimal solutions were found taking into account two objectives, namely the accuracy of the identified key variables and the cost of additional measurements. The results of this multi-objective optimization problem were represented in a Pareto-optimal front. The presented procedure was applied to a full-scale WWTP. Detailed analysis of the relation between measurements allowed the determination of groups of overlapping mass balances. Adding measured variables could only serve in identifying key variables that appear in the same group of mass balances. Besides, the application of the experimental design procedure to these individual groups significantly reduced the computational effort in evaluating available measurements and planning additional monitoring campaigns. The proposed procedure is straightforward and can be applied to other WWTPs with or without prior data collection. Graphical abstract: Highlights: Step-wise measurement planning procedure to obtain reliable data from wastewater treatment plants (WWTPs). Right combinations of measurements guarantee improvement of key variables. Clustering in groups of overlapping mass balances speeds up calculation. Optimal solutions are trade-off between measurement cost and variable accuracy. Procedure is demonstrated for case study and straightforward to apply to other WWTPs.