Model of steady‐state‐biofilm kinetics

A steady‐state biofilm is defined as one that has neither net growth nor decay over time. The model, developed for steady‐state‐biofilm kinetics with a single substrate, couples the flux of substrate into a biofilm to the mass (or thickness) of biofilm that would exist at steady‐state for a given bulk substrate concentration. Based on kinetic and energetic constraints, this model predicts for a single substrate that a steady‐state bulk concentration, S_min, exists below which a steady‐state biofilm cannot exist. Thus, in the absence of adsorption of bacteria from the bulk water and for substrate concentration below S_min, substrate flux and biofilm thickness are zero. Equations are provided for calculating the steady‐state substrate flux and biofilm thickness for S greater than S_min. An example is provided to demonstrate the use of the steadystate model.