Parameter identification of thermophilic anaerobic degradation of valerate

X Flotats, Birgitte Kiær Ahring, Irini Angelidaki

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearch

Abstract

Mathematical model of the decomposition of valerate presents 3 unknown kinetic parameters, 2 unknown stoichiometric coefficients and 3 unknown initial concentrations for biomass. Applying a structural identifiability study, it is concluded that it is necessary to perform simultaneous batch experiments have been done at 55 degree C, charcterised by four different initial acetate concentrations. Product inhibition of valerate degradation by acetate is considered. Practical identification has been done optimising the sum of the multiple determination coefficients for all measured state variables and for all experiments simultaneously. The estimated values of kinetic parameters have been 0.676 d^-1 for the maximum growth rate (um), 0.176 g Val/L for the saturation constant (Ks) and 0.405 g Ac/L for the constant of acetate inhibition (Kin), considering Monod kinetics and a non-competitive inhibition form. Stoichiometry of valerate anaerobic decomposition has also been established, with the following yeild coefficients: 0.072 g biomass/g Val, 0.52 g Ac/g Val and 0.73 g Pr/g Val. Kinetic parameter values are not significantly different from kinetic values for butyrate anaerobic degradation found in the literature. Results have bann characterised by the parameter correlation matrix and applying the t-Student test at 5% significance level with positive results except for Ks parameter, for which more experiments for improving its identifiability should be done.
Original languageEnglish
Title of host publicationAnaerobic digestion for sustainability in waste (water) treatment and re-use : Proceedings of 7th FAO/SREN-Workshop, 19-22 May 2002, Moscow, Russia
Place of PublicationMoscow
PublisherDepartment of Chemical Enzymology, Chemistry Faculty, Moscow State University
Publication date2002
Pages67-83
Publication statusPublished - 2002
Event7th FAO/SREN-Workshop - Moscow, Russian Federation
Duration: 19 May 200222 May 2002
Conference number: 7

Workshop

Workshop7th FAO/SREN-Workshop
Number7
CountryRussian Federation
CityMoscow
Period19/05/200222/05/2002

Keywords

  • Identifiability
  • Mathematical modelling
  • Calibration
  • Valerate
  • Anaerobic
  • Optimisation

Cite this

Flotats, X., Ahring, B. K., & Angelidaki, I. (2002). Parameter identification of thermophilic anaerobic degradation of valerate. In Anaerobic digestion for sustainability in waste (water) treatment and re-use: Proceedings of 7th FAO/SREN-Workshop, 19-22 May 2002, Moscow, Russia (pp. 67-83). Department of Chemical Enzymology, Chemistry Faculty, Moscow State University.