We analyse the steady-state operation of a continuous flow bioreactor for the two models. In chapter 2 we investigate a simple model for the wastewater treatment, in which the reaction is assumed to be governed by the Monod growth kinetics. The steady-state solutions are found and their stability determined as a function of residence time. The performance of the bioreactor at large residence times is obtained. Knowledge of the steady-state solutions and their asymptotic limits may be useful to estimate parameter values from the experimental data.
In chapter 3 we investigate an extension of the basic model for the activated sludge process. The steady-state solutions are found and their stability determined as a function of residence time. We use steady-state analysis to investigate how the amount of sludge formed depends upon the residence time and the use of a settling unit. We show that when the steady-state sludge content is plotted as a function of the residence time that there are three generic response diagrams, depending upon the value of the effective recycle parameter. Knowledge of the steady-state solutions and their asymptotic limits may be useful to estimate parameter values from the experimental data.