Analysis of a chemostat model with variable yield coefficient: Contois kinetics

Authors

  • Rubayyi Turki Alqahtani Wollongong University
  • Mark I Nelson Wollongong University
  • Annette L Worthy Wollongong University

DOI:

https://doi.org/10.21914/anziamj.v53i0.5093

Keywords:

bioreactor, Chemostat, Contois growth kinetics, Oscillations

Abstract

Food processing wastewaters and slurries typically contain high concentrations of biodegradable organic matter. Before the wastewater can be discharged, the pollutant concentration must be reduced. One way to achieve this is by using a biological species (biomass) that consumes the organic matter (substrate). We investigate an unstructured kinetic model for a bioreactor with a variable yield coefficient, taking into account the death rate of the microorganisms. The growth rate is given by a Contois expression, which is often used to model the growth of biomass in wastewaters containing biodegradable organic materials. The analysis shows that the system has natural oscillations for some ranges of the parameters. We also investigate the effects of the death rate parameter on the region of periodic behaviour. References
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Author Biographies

Rubayyi Turki Alqahtani, Wollongong University

SCHOOL OF MATHEMATICS AND APPLIED STATISTICS

Mark I Nelson, Wollongong University

SCHOOL OF MATHEMATICS AND APPLIED STATISTICS

Annette L Worthy, Wollongong University

SCHOOL OF MATHEMATICS AND APPLIED STATISTICS

Published

2012-05-28

Issue

Section

Proceedings Engineering Mathematics and Applications Conference