Practical identifiability of biokinetic parameters of a model describing two‐step nitrification in biofilms
- 15 April 2008
- journal article
- research article
- Published by Wiley in Biotechnology & Bioengineering
- Vol. 101 (3), 497-514
- https://doi.org/10.1002/bit.21932
Abstract
Parameter estimation and model calibration are key problems in the application of biofilm models in engineering practice, where a large number of model parameters need to be determined usually based on experimental data with only limited information content. In this article, identifiability of biokinetic parameters of a biofilm model describing two-step nitrification was evaluated based solely on bulk phase measurements of ammonium, nitrite, and nitrate. In addition to evaluating the impact of experimental conditions and available measurements, the influence of mass transport limitation within the biofilm and the initial parameter values on identifiability of biokinetic parameters was evaluated. Selection of parameters for identifiability analysis was based on global mean sensitivities while parameter identifiability was analyzed using local sensitivity functions. At most, four of the six most sensitive biokinetic parameters were identifiable from results of batch experiments at bulk phase dissolved oxygen concentrations of 0.8 or 5 mg O2/L. High linear dependences between the parameters of the subsets and resulted in reduced identifiability. Mass transport limitation within the biofilm did not influence the number of identifiable parameters but, in fact, decreased collinearity between parameters, especially for parameters that are otherwise correlated (e.g., µAOB and , or µNOB and ). The choice of the initial parameter values had a significant impact on the identifiability of two parameter subsets, both including the parameters µAOB and . Parameter subsets that did not include the subsets µAOB and or µNOB and were clearly identifiable independently of the choice of the initial parameter values. Biotechnol. Bioeng. 2008;101: 497–514.Keywords
This publication has 46 references indexed in Scilit:
- Experimental and theoretical study of membrane-aerated biofilm reactor behavior under different modes of oxygen supply for the treatment of synthetic wastewaterChemical Engineering Science, 2006
- Decay processes of nitrifying bacteria in biological wastewater treatment systemsWater Research, 2006
- Determination of the decay rate of nitrifying bacteriaBiotechnology & Bioengineering, 2006
- Biogeochemical model of Lake Zürich: sensitivity, identifiability and uncertainty analysisEcological Modelling, 2001
- Modeling of aerated upflow fixed bed reactors for nitrificationWater Science & Technology, 1999
- Dynamics of artificially immobilizedNitrosomonas europaea: Effect of biomass decayBiotechnology & Bioengineering, 1997
- Development of a dynamic model describing nitritification and nitratification in trickling filtersWater Research, 1997
- Modelling the effect of oxygen concentration on nitrite accumulation in a biofilm airlift suspension reactorWater Science & Technology, 1997
- Optimal design of in-sensor-experiments for on-line modelling of nitrogen removal processesWater Science & Technology, 1995
- Influence of substrate c/n ratio on the structure of multi-species biofilms consisting of nitrifiers and heterotrophsWater Science & Technology, 1995