Regular articleThree-phase fluidized bed bioreactor modelling and simulation

- An improved mathematical model of a three-phase fluidized-bed bioreactor for aerobic processes was proposed.
- Nonlinear analysis of steady states and dynamics of such bioreactors were performed.
- New simplified method for the determination of local stability of bioreactors was proposed.
- Existence of sustained oscillations of state variables in the bioreactor was revealed.
- Conditions for biofilm existence on carrier particles were determined.

A mathematical model of a three-phase fluidized bed biofilm reactor for aerobic processeses is presented. The growth of attached biomass, its decay and interphase transfer were taken into consideration in the proposed quantitative description of the bioreactor. The presented model of the fluidized-bed bioreactor is the unique one which takes into account partial thickening of biomass and its recirculation. The stationary characteristics was determined with the use of a novel simplified numerical method for the assessment of stability of steady states. The effect of microbial growth kinetics on steady state multiplicity was characterized. The relationship between biofilm growth and boundaries of fluidized bed existence was shown. Conditions of the biofilm's existence on carrier particles were formulated. Some novel dynamic characteristics concerning fluidized bed bioreactors were presented.

138